I HC QUC GIA H NI TRNG I HC KHOA HC T NHIN

L KHC QUYT

NGHIN CU MT S C IM SINH THI CA VOC MI HCH (RHINOPITHECUS AVUNCULUS DOLLMAN, 1912) KHU VC KHAU CA, TNH H GIANG

LUN VN THC S KHOA HC

H NI 2006

I HC QUC GIA H NI TRNG I HC KHOA HC T NHIN

L KHC QUYT

NGHIN CU MT S C IM SINH THI CA VOC MI HCH (RHINOPITHECUS AVUNCULUS DOLLMAN, 1912) KHU VC KHAU CA, TNH H GIANG

Chuyn ngnh: M s:

ng vt hc 01. 05. 02

LUN VN THC S KHOA HCNgi hng dn khoa hc: GS. TS. L V KHI

H NI 2006

Voc mi hch (Rhinopithecus avunculus Dollman, 1912) khu vc Khau Ca, tnh H Giangnh: L Khc Quyt

*

Ch : Tt c cc nh trong lun vn ny c chp bi tc gi, ngoi tr mt s khc c ghi ch r rng

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LI CM NTrong sut qu trnh hc tp v nghin cu, ti nhn c rt nhiu s ng vin v gip nhit tnh ca nhiu c nhn v t chc. Ti v cng bit n tt c! Ti xin by t lng knh trng v bit n su sc ti GS. TS. L V Khi (Khoa Sinh hc, Trng i hc KHTN-HQGHN), ngi hng dn khoa hc tn tnh v chu o trong sut qu trnh nghin cu v hon thnh lun vn ny. Ti xin by t lng bit n i vi: GS. TS. Herbert H. Covert (Trng i hc Colorado, Boulder, Hoa K) v TS. Barth W. Wright (Trng i hc thnh ph Kansas, Hoa K) v nhng gip v ng vin cng nh cc h tr v kinh ph v thit b nghin cu; CN. V Ngc Thnh (Khoa Sinh hc, Trng i hc KHTN HQGHN) lun gip v ng vin cho ti trong cuc sng v cng tc nghin cu. Xin gi li cm n trn trng n cc c quan: T chc Bo tn ng, Thc vt hoang d Quc t (FFI), Tp on Vin thng Vodafone (Vodafone Group Plc.), Qu Cc loi u tin (Flagship Species Fund) v T chc Bo tn Linh trng (Primate Conservation Inc.) ti tr kinh ph trong sut qu trnh nghin cu; UBND tnh H Giang v Chi cc Kim lm tnh H Giang to iu kin v cp giy php cho vic nghin cu thc a; v B mn ng vt C xng sng, Khoa Sinh hc, Trng i hc KHTN HQGHN gip v to iu kin cho ti trong qu trnh hc tp. Ti xin gi li cm n chn thnh ti GS. TSKH. Nguyn Ngha Thn (Khoa Sinh hc, Trng i hc KHTN HQGHN) tn tnh gip ti nh tn cc loi thc vt. Ti cng xin gi li cm n ti CN. Nguyn Anh c v CN. V Anh Ti (Khoa Sinh hc, Trng i hc KHTN HQGHN) gip qu bu v tham gia vi ti trong cng tc nghin cu khu h thc vt khu vc Khau Ca. Ti xin gi li cm n chn thnh ti cc c nhn: TS. Mark Infield, TS. William B. Bleisch, b Nguyn Bch H, b L Th Yn Anh v ng Paul Insua-Cao

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(FFI), ng Robert Primmer (T chc FRR) gip v to iu kin thun li cho ti nghin cu v hc tp; TS. Noel Rowe v TS. Marc Myers (PCI) ng vin v ti tr kinh ph; PGS. TS. H nh c (Khoa Sinh hc, Trng i hc KHTN HQGHN), TS. Ramesh Boonratana (Tng th k, Hip hi Linh trng ng Nam SEAPA), NCS. Hong Minh c (Vin Sinh hc Nhit i/i hc Queensland Australia) ng vin v gip qu bu v hc thut v ti liu tham kho; NCS. Cyril C. Grter (Anthropological Institute v Museum, Universitt Zrich), ThS. Carrie Stengel (Trng i hc Colorado, Boulder, Hoa K) cung cp nhiu ti liu tham kho; ng Hong Ngc Tng, ng Hong Vn Nnh v ng Hong Vn Tu (Chi cc Kim lm tnh H Giang) gip v to iu kin thun li cho ti trong qu trnh nghin cu ti H Giang; ThS. Nguyn i Trung (Vin nghin cu a cht v Khong sn) v b Nguyn Hnh Quyn (Vin a l) cung cp v gip x l s liu bn . Ti xin gi li cm n ti nhn dn x Tng B, huyn V Xuyn, tnh H Giang, c bit cc anh n Vn Khoan, n Vn Nhiu, Nng Vn Gii, Chng Vn Thnh, n Vn Khon, n Vn Truyn v ng n Vn Mai gip c bit cho ti trong sut qu trnh nghin cu thc a. Cui cng, ti xin by t lng bit n su sc i vi M, v v gia nh cng bn b, v s n cn, h tr ht lng v s cm thng i vi cng vic nghin cu thc a v hc tp ca ti. H Ni, ngy 05 thng 12 nm 2006 L Khc Quyt

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MC LCLI CM N.................................................................................................................. ii MC LC ...................................................................................................................... iv DANH MC CC CH VIT TT............................................................................. vi DANH MC CC BNG.............................................................................................. vi DANH MC CC HNH .............................................................................................. vi M U.......................................................................................................................... 1 Chng 1 TNG QUAN TI LIU............................................................................ 3 1.1. S lc v lch s nghin cu Linh trng Vit Nam...................................... 3 1.1.1. Giai on trc nm 1954................................................................................ 3 1.1.2. Giai on t nm 1954 n nm 1975 .............................................................. 4 1.1.3. Giai on t sau nm 1975 n nay.................................................................. 4 1.2. Mt s vn v phn loi hc Linh trng Vit Nam ................................... 5 1.3. Mt vi c im ca ging Rhinopithecus.......................................................... 8 1.3.1. Phn loi hc ................................................................................................... 8 1.3.2. Hnh thi.......................................................................................................... 9 1.3.3. Mt s c im sinh hc, sinh thi ............................................................... 10 1.3.4. Phn b.......................................................................................................... 11 1.4. Vi nt v loi Voc mi hch (Rhinopithecus avunculus) ................................ 11 1.4.1. Tn gi .......................................................................................................... 11 1.4.2. Phn loi hc ................................................................................................. 12 1.4.2. Mt s c im hnh thi.............................................................................. 12 1.4.3. Mt s c im sinh hc, sinh thi ............................................................... 13 1.4.4. Phn b.......................................................................................................... 15 1.4.5. Cc mi e da .............................................................................................. 15 1.4.6. Tnh trng bo tn.......................................................................................... 17 Chng 2 A IM, THI GIAN V PHNG PHP NGHIN CU............ 19 2.1. a im nghin cu........................................................................................... 19 2.1.1. L do la chn khu vc nghin cu ............................................................... 19 2.1.2. iu kin t nhin ......................................................................................... 19 2.1.3. iu kin kinh t-x hi................................................................................. 27 2.2. Thi gian nghin cu.......................................................................................... 30 2.3. Phng php nghin cu ................................................................................... 31 2.3.1. Phng php iu tra theo tuyn .................................................................... 31 2.3.2. Phng php theo di i tng nghin cu .................................................. 31 2.3.3. Phng php xc nh cc nhm tui/gii tnh............................................... 31 2.3.4. Phng php iu tra thnh phn thc n....................................................... 31 2.3.5. Phng php nghin cu vng sng............................................................... 33 2.3.6. Phng php nghin cu v cc kiu vn ng v t th................................ 33 2.3.7. Phng php nghin cu cu trc rng .......................................................... 33 2.3.8. Phng php theo di vt hu ........................................................................ 34 2.3.9. Phng php phn tch s liu ....................................................................... 34 Chng 3 KT QU NGHIN CU V THO LUN......................................... 35 3.1. Qun th Voc mi hch khu vc Khau Ca ................................................... 35 3.1.1. S lng qun th .......................................................................................... 35

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3.1.2. Kch thc v cu trc n............................................................................. 36 3.1.3. T chc n ................................................................................................... 36 3.1.4. Mt s c im hnh thi theo cc nhm tui v gii tnh............................. 38 3.2. Mt s tp tnh ca Voc mi hch.................................................................... 39 3.2.1. Kim n (Feeding) ......................................................................................... 39 3.2.2. Tp tnh x hi (Social behaviour) ................................................................. 39 3.2.3. Ngh ngi (Resting) ....................................................................................... 41 3.2.4. Di chuyn (Traveling).................................................................................... 41 3.3. Mt s c im sinh thi dinh dng............................................................... 42 3.3.1. Thnh phn thc n........................................................................................ 42 3.3.2. Ngun thc n ............................................................................................... 47 3.4. Vng sng ........................................................................................................... 48 3.4.1. Ni sng ........................................................................................................ 48 3.4.2. Kch thc vng sng .................................................................................... 50 3.4.3. S dng vng sng ........................................................................................ 52 3.4.4. Ni ng.......................................................................................................... 53 3.5. Cc kiu t th v vn ng............................................................................... 54 3.5.1. Cc kiu t th............................................................................................... 54 3.5.2. Cc kiu vn ng ......................................................................................... 57 3.6. Mt s vn v bo tn Voc mi hch khu vc Khau Ca.......................... 60 3.6.1. Cc mi e da .............................................................................................. 60 3.6.2. Cc hot ng bo tn.................................................................................... 63 3.6.3. S tham gia ca cng ng a phng.......................................................... 64 3.6.4. Tm quan trng ca khu vc Khau Ca i vi bo tn Voc mi hch........... 64 KT LUN V KIN NGH....................................................................................... 66 Kt lun ..................................................................................................................... 66 Kin ngh ................................................................................................................... 68 Danh mc cc cng trnh ca tc gi lin quan n lun vn ..................................... 69 Ti liu tham kho ........................................................................................................ 70 Ph lc 1. Danh lc cc loi linh trng Vit Nam .......................................................... I Ph lc 2. Cc loi thuc ging Rhinopithecus ..................................................................II Ph lc 3. Cc mu phiu thu thp s liu ....................................................................... III Ph lc 4. Thi gian v s lng quan st Voc mi hch khu vc Khau Ca ................ IV Ph lc 5. Danh sch cc loi thc vt l thc n ca Voc mi hch.............................. VI Ph lc 6. S lng cc loi l thc n ca Voc mi hch theo cc tuyn thc vt......... XI Ph lc 7. Danh sch cc loi thc vt thuc cc tuyn iu tra thc vt......................... XII Ph lc 8. D n Bo tn Voc mi hch H Giang .................................................. XVI Ph lc 9. Mt s hnh nh ghi nhn c trong khi nghin cu.................................. XVII

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DANH MC CC CH VIT TTB KHCN&MT DBH HQGHN FFI IUCN KBTTN KHTN n r VQG Vin NC C-KS UBND WWF B Khoa hc, Cng ngh v Mi trng ng knh ngang ngc i hc Quc gia H Ni T chc Bo tn ng, Thc vt hoang d Quc t Hip hi Quc t v Bo tn Thin nhin Khu Bo tn Thin nhin Khoa hc T nhin S lng mu (o, m, bt gp, quan st, v.v..) Gi tr ca mu (n) Vn Quc gia Vin Nghin cu a cht v Khong sn y ban Nhn dn Qu Bo tn Thin nhin Th gii

DANH MC CC BNGBng 1. Mt s c im hnh thi ca cc loi thuc ging Rhinopithecus ....................... 9 Bng 2. Mt s c im sinh thi ca cc loi thuc ging Rhinopithecus ..................... 10 Bng 3. Kch thc v trng lng ca Voc mi hch (Rhinopithecus avunculus)......... 13 Bng 4. S liu sinh kh hu Trm kh tng H Giang ................................................ 22 Bng 5. Danh sch cc loi thc vt qu him ghi nhn khu vc Khau Ca.................... 26 Bng 6. Danh sch cc loi th qu him khu vc Khau Ca ......................................... 27 Bng 7. Hin trng dn s v dn c ca khu vc Khau Ca, tnh H Giang ..................... 29 Bng 8. Bng xc nh cc phn ca cy b Voc mi hch n ........................................ 33 Bng 9. S lng qun th ca Voc mi hch cc khu vc phn b khc nhau ........... 35 Bng 10. Danh sch cc loi thc vt l thc n ca Voc mi hch Khau Ca .............. 43 Bng 11. S lng cc loi thuc cc tuyn iu tra thc vt l thc n ca Voc mi hch khu vc Khau Ca, tnh H Giang .......................................... 48

DANH MC CC HNHBn 1. Phn b ca Voc mi hch (Rhinopithecus avunculus) Vit Nam ............... 16 Bn 2. V tr khu vc Khau Ca, tnh H Giang............................................................ 20 Bn 3. H thng tuyn iu tra v v tr cc tuyn iu tra thc vt ............................. 32 Bn 4. Cc im ghi nhn Voc mi hch khu vc Khau Ca................................... 51 Biu 1. Biu sinh kh hu H Giang (cch Khau Ca 15 km) ................................ 22 Biu 2. Thnh phn thc n ca Voc mi hch khu vc Khau Ca .......................... 42 Biu 3. S thay i thc n theo ma ca Voc mi hch khu vc Khau Ca............ 46 Biu 4. S thay i theo ma ca cc loi thc vt khu vc Khau Ca ...................... 46 Biu 5. S lng cc cy theo cc tuyn iu tra thc vt khu vc Khau Ca ............ 50 nh 1. Voc mi hch th hin s da nt khi nhn thy vt th l (con ngi) ............... 40 nh 2. Khu rng c Voc mi hch kim n................................................................... 49

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nh 3. Kiu ngi co gi ca Voc mi hch.................................................................... 54 nh 4. Kiu ngi dng chn ca Voc mi hch ............................................................. 54 nh 5. Kiu ngi vi chi trc u bm ca Voc mi hch............................................. 55 nh 6. Kiu m bm ca Voc mi hch ........................................................................ 55 nh 7. Kiu ng ca Voc mi hch ............................................................................. 56 nh 8. Kiu ci mnh ca Voc mi hch ....................................................................... 56 nh 9. Kiu ng bng hai chi sau ca Voc mi hch ................................................... 56 nh 10. Kiu u bm bng chi trc ca Voc mi hch ................................................ 57 nh 11. Kiu i bng bn chi ca Voc mi hch ........................................................... 57 nh 12. Kiu chy bng bn chn ca Voc mi hch .................................................... 57 nh 13. Kiu leo ln theo chiu thng ng ca Voc mi hch ..................................... 58 nh 14. Kiu Di chuyn bng chi trc ca Voc mi hch............................................ 58 nh 15. Kiu nhy lao xung ca Voc mi hch ........................................................... 59 nh 16. Kiu nhy dng ca Voc mi hch................................................................... 59 nh 17. Kiu nhy m thng ng ca Voc mi hch ................................................... 60 nh 18. Kiu bung mnh ca Voc mi hch ................................................................ 60 nh 19. Voc mi hch vng (R. roxellana)......................................................................II nh 20. Voc mi hch Vn Nam (R. bieti) ......................................................................II nh 21. Voc mi hch Qu Chu ....................................................................................II nh 22. Voc mi hch (R. avunculus) .............................................................................II

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M UVoc mi hch (Rhinopithecus avunculus Dollman, 1912) l mt trong nhng loi linh trng nguy cp nht trn th gii [69, 89]. y l loi linh trng c hu cho vng ng Bc Vit Nam. Mc d, Voc mi hch c pht hin v nh tn t nm 1912 [32], nhng c rt t nhng quan st v loi ny trong mt thi gian di sau , do vy, Mettermeier v Cheney (1986) cho rng: Voc mi hch (Rhinopithecus avunculus) min Bc Vit Nam c th tuyt chng. Loi ny ch c bit n qua mt s mu vt bo tng c thu thp t u th k ny v gn y khng c bt k bo co no v chng ngoi t nhin [68]. Cho n nm 1990, Ratajszczak v cng s tin hnh mt cuc iu tra cho WWF khu vc xung quanh VQG Ba B v thu thp c nhng thng tin v loi Voc mi hch Ba B v c cc khu vc khc [87]. Tip sau , Ratajszczak v cng s (1992) thc hin mt cuc iu tra tng th u tin v loi Voc mi hch (R. avunculus) nhiu a phng [88]. Kt qu ca cuc iu tra ny ti pht hin v s tn ti ca loi ny trong t nhin, vi s lng qun th c on khong 190-250 c th khu vc Chim Ha v N Hang, tnh Tuyn Quang, v khong 100 c th cc khu vc thuc 2 tnh Bc Kn v Thi Nguyn [88]. Kt qu iu tra, nghin cu cho thy, Voc mi hch (R. avunculus) hin hnh thnh mt s qun th : Phn khu Tt K (khong 20 c th) v phn khu Bn Bung (khong 50 c th) ca KBTTN Na Hang thuc tnh Tuyn Quang, v khu vc Khau Ca (khong 60 c th) ca tnh H Giang [19, 26, 55, 56, 57, 58, 61, 73, 77]. Tuy vy, cho n nay, nhng hiu bit v c im sinh hc, sinh thi ca loi Voc mi hch ch qua kt qu ca mt s t nghin cu ban u ca Boonratana v L Xun Cnh (1994) v sinh thi v tp tnh ca Voc mi hch KBTTN Na Hang [19, 20]; ca Phm Nht (1993) v thc n v kt qu ca cc

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cuc iu tra thc a v Voc mi hch mt s khu vc thuc vng ng Bc Vit Nam [7]; v ca mt s tc gi khc [2, 29, 54, 55, 66]. Ti khu vc Khau Ca, tnh H Giang, mt qun th Voc mi hch (Rhinopithecus avunculus), vi khong 60 c th, c pht hin vo thng 01 nm 2002 [55]. K t , qun th Voc mi hch ny c xc nh l mt trong ba qun th ln nht v quan trng i vi cng tc nghin cu v bo tn loi linh trng qu him ny [26]. Nhm gp phn nghin cu v bo tn loi Voc mi hch khu vc Khau Ca, tnh H Giang, chng ti thc hin ti: Nghin cu mt s c im sinh thi ca Voc mi hch (Rhinopithecus avunculus Dollman, 1912) khu vc Khau Ca, tnh H Giang, vi mc ch: 1. Nghin cu mt s c im sinh hc, sinh thi ca qun th Voc mi hch khu vc Khau Ca, tnh H Giang. 2. Nghin cu mt s tp tnh ca Voc mi hch khu vc Khau Ca, tnh H Giang. 3. Nghin cu mt s c im sinh thi dinh dng: thnh phn thc n, ngun thc n sn c, tr lng v s bin ng ngun thc n ca Voc mi hch khu vc Khau Ca, tnh H Giang. 4. Nghin cu v vng sng v s dng vng sng ca Voc mi hch khu vc Khau Ca, tnh H Giang. 5. M t cc kiu t th v vn ng ca Voc mi hch khu vc Khau Ca, tnh H Giang. Kt qu nghin cu ca ti s gp phn nng cao hiu bit v nhng c im sinh hc v sinh thi ca Voc mi hch (R. avunculus), to c s khoa hc cho cng tc bo tn loi linh trng qu him ny. y cng l nghin cu u tin v Voc mi hch khu vc Khau Ca, tnh H Giang.

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Chng 1 TNG QUAN TI LIU1.1. S lc v lch s nghin cu Linh trng Vit NamCc nghin cu v ng vt hoang d, trong c cc loi linh trng, Vit Nam c bt u ch yu t nhng nm cui th k XIX do cc nh khoa hc nc ngoi thc hin. K t nhng nm 1960 n nay, c nhiu nghin cu chuyn su v cc loi linh trng c cc nh khoa hc Vit Nam thc hin cng vi cc iu tra v nghin cu v a dng sinh vt. S lc v lch s nghin cu linh trng Vit Nam c th c chia thnh 3 giai on sau:

1.1.1. Giai on trc nm 1954Trong giai on ny, cc nghin cu v th, trong c cc loi linh trng, ch yu c thc hin bi cc nh khoa hc ngi nc ngoi. Cc nh nghin cu tiu biu v cc loi th, trong c cc loi linh trng, Vit Nam trong giai on , c th k n: George Finlayson (1828), Mine-Edwards (1867 1874), Morice (1904), Brousniche (1887), Billet (1896 1898), Pavie (1879 1898), Boutan (1900 1906), De Pousargues (1904), Menegeaux (1905-1906), Delacour (1928 1930), H.t Stevens (1923 1924), Kelly Rooservelts (1928 1929), Bourret (1942, 1944), v.v... C th ni, nhng kt qu nghin cu v linh trng Vit Nam, trc nm 1954, phn ln l mt phn kt qu nghin cu ca cc nh nghin cu nc ngoi thng qua cc cuc iu tra v nghin cu thm him nhm pht hin, m t loi mi, phn loi v thng k thnh phn loi, cha c cc cng trnh nghin cu chuyn su v cc c im sinh hc, sinh thi v bo tn cc loi linh trng. Trong sut thi k khng chin chng Php (1945 1954), mi hot ng nghin cu trc tip v cc loi th ni chung, cc loi linh trng ni ring, Vit Nam b gin on.

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1.1.2. Giai on t nm 1954 n nm 1975Sau khi min Bc c hon ton gii phng (thng 10 nm 1954), cc nghin cu v a dng sinh vt, trong c cc loi linh trng c tip tc v pht trin. min Bc Vit Nam, cc nh khoa hc Vit Nam tin hnh nhiu cuc iu tra, nghin cu v thnh phn loi ca cc khu h v c mt s c im sinh hc, sinh thi ca cc loi th ni chung v cc loi linh trng ni ring nhiu tnh min Bc Vit Nam, trong giai on 1956 1971 [12]. min Nam Vit Nam, ch c rt t iu tra, nghin cu c thc hin trong thi gian ny; ng ch l cc cng trnh ca Van Peenen v cng s (1969) [95]. Cc nghin cu v linh trng c gi tr khoa hc trong thi gian ny phi k n cc cng trnh l: Nm 1960, o Vn Tin vi cng trnh Sur une Nouvelle Espece de Nycticebus au Vietnam m t mt loi Cu li mi Cu li nh (Nycticebus intermedius) Vit Nam [103]. Nm 1970, o Vn Tin vi cng trnh Sur les formes de semnopithque

noir Presbytis francoisi (Colobidae, Primates) au Vietnam et description dune forme nouvelle nghin cu v cc phn loi ca loi Voc en m trng (Presbytis francoisi) v m t mt phn loi voc mi Voc H Tnh (Presbytis francoisi hatinhensis) [104]. Nm 1973, L Hin Ho xut bn cun: Th kinh t min Bc Vit Nam, tp 1, cung cp nhng thng tin v phn b, c im sinh hc v gi tr kinh t ca 9 loi linh trng min Bc Vit Nam [4]. Kt qu ca cc cuc iu tra th min Bc Vit Nam c o Vn Tin (1985) tng kt trong cun: Kho st th min Bc Vit Nam [12].

1.1.3. Giai on t sau nm 1975 n nayCc iu tra, nghin cu v bo tn a dng sinh vt, c bit i vi cc loi linh trng, c quan tm v trin khai mnh m trn cc vng ca c nc v t c rt nhiu kt qu c gi tr. i ng cn b Vit Nam nghin cu v linh

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trng cng pht trin v ln mnh khng ngng. Rt nhiu nghin cu khng ch b hp do cc cn b khoa hc Vit Nam tin hnh, m cn c s hp tc quc t su rng vi cc chuyn gia linh trng v cc t chc bo tn quc t. Trong giai on ny, c nhiu cng trnh tiu biu nghin cu v Linh trng Vit Nam ca nhiu tc gi trong v ngoi nc thc hin [3, 7, 10, 19, 20, 22, 37, 39, 53, 60, 61, 62, 64, 70, 71, 79, 88]. c bit, trong nhng nm gn y, cng tc iu tra, nghin cu, bo tn v pht trin cc loi linh trng qu him v ang c ch trng. Hng lot cc VQG v KBTTN c thnh lp trn khp c nc bo tn a dng sinh vt, trong c cc loi linh trng qu him. Mt s chng trnh nghin cu v sinh thi v tp tnh ca cc loi linh trng v ang c tin hnh. Kt qu ca cc iu tra, nghin cu v khu h linh trng ca cc a phng, cc vng min v cc cng trnh nghin cu v sinh hc, sinh thi ca cc loi linh trng Vit Nam c cng b trn cc tp ch khoa hc trong nc v quc t.

1.2. Mt s vn v phn loi hc Linh trng Vit NamTheo h thng phn loi ca Brandon-Jones v cng s (2004), khu h linh trng Vit Nam c 24 loi v phn loi thuc 3 h l: h Cu li (Loridae), h Kh (Cercopithecidae) v h Vn (Hylobatidae) [21] (Ph lc 1). Trong s 24 loi v phn loi, 6 loi v phn loi l c hu ca Vit Nam, l: Voc mi hch (Rhinopithecus avunculus), Voc mng trng (Trachypithecus delacouri), Voc u trng (Trachypithecus poliocephalus poliocephalus), Ch v chn xm (Pygathrix nemaeus cinerea), Kh ui di Cn o (Macaca fascicularis condorensis) v Vn en (Nomascus nasutus nasutus). Vit Nam, h Cu li (Loridae) ch c 1 ging (Nycticebus) vi hai loi cu li l: Cu li ln (Nycticebus bengalensis) v Cu li nh (N. pygmaeus). Loi Cu li nh (N. intermedius) c o Vn Tin m t vo nm 1960 [103] c coi ng loi vi loi Cu li nh (N. pygmaeus) [5, 6, 10, 40].

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H Kh (Cercopithecidae), Vit Nam, c hai phn h: phn h Kh (Cercopithecinae) v phn h Voc (Colobinae), vi 4 ging: Macaca, Trachypithecus, Pygathrix v Rhinopithecus. y l h c s loi v phn loi phong ph nht, vi 17 loi v phn loi. Trong , phn h Kh (Cercopithecinae) ch c 1 ging (Macaca) gm 6 loi v phn loi, c bit phn loi Kh ui di Cn o (M. fascicularis condorensis) l phn loi c hu ca Vit Nam hin ch c phn b mt s o thuc VQG Cn o [21]. Phn h Voc (Colobinae) c 3 ging: Trachypithecus (7 loi v phn loi), Pygathrix (3 loi v phn loi) v Rhinopithecus (1 loi). y l phn h c nhiu kin tranh lun khc nhau v phn loi hc. V ging Trachypithecus, hin c kh nhiu kin khc nhau v phn loi hc ca mt s loi v phn loi ca ging ny. V d, nhng kin trc y cho rng loi Voc en m trng (Trachypithecus francoisi) Vit Nam c cc phn loi: Voc en m trng (T. f. francoisi), Voc mng trng (T. f. delacouri), Voc u trng (T. f. poliocephalus), Voc H Tnh (T. f. hatinhensis) v Voc en tuyn (T. f. ebenus) [5, 10, 12, 22, 25]. Tuy nhin, Groves (2001) nng cc phn loi ny thnh cc loi khc nhau [40]. Theo nhng nghin cu gn y ca Roos (2004) v Brandon-Jones v cng s (2004), phn loi Voc mng trng (T. f. delacouri) thnh loi Voc mng trng (T. delacouri); phn loi Voc u trng (T. f. poliocephalus) i thnh loi Voc Ct B (T. poliocephalus poliocephalus), cc phn loi cn li vn gi nguyn l Voc en m trng (T. f. francoisi), Voc H Tnh (T. f. hatinhensis) v Voc en tuyn (T. f. ebenus) [21, 90]. Voc bc trc y c bit vi tn khoa hc l T. cristatus [5, 6, 10, 12, 22, 25, 40]. Cn c theo cc kt qu phn tch v di truyn hc v phn b a l, hin nay, Voc bc Vit Nam c coi l mt phn loi Voc bc (Trachypithecus villosus margarita) [21, 74, 90]. Voc xm trc y c bit vi tn khoa hc l T. phayrei [5, 6, 10, 12, 22, 25, 40], sau c nh tn l T. crepusculus [73, 90]. Theo kt qu nghin cu v h thng phn loi gn y nht ca Brandon-Jones v cng s (2004) v

6

ng Tt Th (2005) Voc xm, Vit Nam, c xem l mt phn loi Voc xm (Trachypithecus barbei holotephreus) [11, 21]. Do nhng c im ging nhau ca cc loi thuc ging Rhinopithecus v ging Pygathrix, nn mt s nh nghin cu, trc y, xem hai ging ny ch l mt ging Pygathrix [25, 40, 82, 91]. Tuy nhin, nhiu nh nghin cu linh trng vn cho rng Rhinopithecus v Pygathrix l hai ging khc bit [5, 6, 10, 12, 21, 37, 40, 46, 64, 73, 90]. Vit Nam, ging Rhinopithecus ch c 01 loi Voc mi hch (R. avunculus) [6, 10, 21, 73]. Trc y, mt s nh nghin cu cho rng cc loi v phn loi vn ca Vit Nam thuc ging Hylobates [5, 12, 25]. Tuy nhin, qua nhng nghin cu gn y trn c s phn tch v m hc ca ting ht v di truyn hc, cc loi v phn loi vn ca Vit Nam c xp vo ging Nomascus [21, 39, 40, 90]. Hin nay, h Vn (Hylobatidae), Vit Nam, ch c 1 ging (Nomascus) vi 5 loi v phn loi [21, 39, 40, 90]. Vit Nam l mt trong nhng nc phn vng a-ng vt ng Dng (Indo-Chinese subregion) giu v thnh phn loi linh trng. So vi chu (183 loi v phn loi), Vit Nam c 24 loi v phn loi (chim 13,11%) v ch ng sau Indonesia (36,07%), Thi Lan (19,13%), n (15,30%), Trung Hoa (14,75%) v Malaysia (14,21%) [7, 21, 37]. V quan h a l ng vt hc, khu h linh trng Vit Nam c quan h vi cc khu h ph cn, trong yu t ng Dng l tri hn c (vi 17 loi v phn loi, chim 70,83%), tip n l yu t Nam Trung Hoa (vi 9 loi v phn loi, chim 37,50%), n (chim 16,67%), M Lai (chim 8,33%) v t nht l yu t Himalaya (4,17%). Ngoi ra, khi h linh trng Vit Nam cng c t l cao v yu t c hu (chim 25,00%) [7, 21, 37] (Ph lc 1).

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1.3. Mt vi c im ca ging Rhinopithecus 1.3.1. Phn loi hcGing Rhinopithecus l mt nhm linh trng b n thng c bit n vi ci tn l voc mi hch. Ging Rhinopithecus, cng vi cc ging Pygathrix (Voc v), Nasalis (Kh vi), Simias (Kh simakobu hoc kh n l mi hch o Mentawai) v ha thch ca Mesopithecus, thng c gp li vi nhau di mt thut ng khng chnh thc l kh mi k quc (odd-nosed monkeys) do tt c cc taxon ny c im chung: g mc bn ca sn cnh mi ln pht trin, c im ny phn bit chng vi cc taxon khc ca phn h Colobinae [31, 46, 91]. Mi quan h gia hai ging Rhinopithecus v Pygathrix vn cn tranh ci. Hai ging ny c chung mt s c im, nh c mt np da nh ti vnh trn ca hai l mi, s thu hp ca xng mi v s ging nhau v t l cc chi [82]. Da trn nhng c im cu to ging v khc nhau cng nh nhng quan st v cc c im sinh hc ca 2 ging Pygathrix v Rhinopithecus, mt vi tc gi coi ging Rhinopithecus l mt phn ging ca ging Pygathrix [25, 31, 75, 91]. Tuy vy, kt lun ny khng c ng h bi phn ln cc nh linh trng hc Trung Hoa [83, 101]. Nhng nghin cu v hnh thi hc v di truyn t bo c xu hng tch bit hai ging ny v cho thy mi quan h gn gi gia ging Pygathrix vi ging Nasalis hn l vi ging Rhinopithecus [23, 46, 48, 101]. Ngc li vi nhng gi thit ny, trn c s nhng dn liu v gen, Wang v cng s, (1995) cho rng ging Rhinopithecus c quan h gn gi vi ging Presbytis hn (phn h Colobinae sng Thi Lan, Malaysia v qun o Indonesia) [96]. Thm vo , Pocock (1924) quan st thy mu lng ca nhng con non ca cc loi voc c kch thc trung bnh ca chu l mt c im phn bit hu dng mc ging nhau [86]. Mu lng ca nhng con non ca loi Pygathrix nemaeus tng t nh con non ca ging Presbytis [98]. Mt s tc gi ghp ging Rhinopithecus vo ging Pygathrix [25, 91]. Tuy nhin, mu lng ca

8

nhng con non ca loi Rhinopithecus avunculus dng nh c mu xm nht hn [19,20], v do , khc vi cc ging Pygathrix v Presbytis [73]. Phn ln cc nh phn loi hc v chuyn gia linh trng, hin nay, u cng nhn ging Rhinopithecus l mt ging ring bit v trn th gii c 4 loi: Voc mi hch (Rhinopithecus avunculus) c hu ca min Bc Vit Nam, 3 loi khc (R. roxellana, R. bieti v R. brelichi) c hu ca min Nam Trung Hoa [21, 40, 46] (Ph lc 2).

1.3.2. Hnh thiTrong s cc loi kh mi k quc, ging Rhinopithecus c cu to gii phu mi khc bit mi hch do g bn (lateral crura) ca sn cnh mi ln (greater alar cartilage) c gn vi cc xng mi ngn hoc tiu bin, xng vch ngn mi (bony nasal septum) v sn vch ngn (septal cartilage) ngn v pha nh mi (rostrum) [24]. Kt qu thch nghi ca c im gii phu ny hin cha c gii thch cn k, nhng hnh thi mi ca voc mi hch c th c tc dng lm cho khng kh ht th trong iu kin ni cao kh v lnh c m hn v m cao hn [73]. Mt s c im hnh thi ca cc loi voc mi hch c trnh by tm tt Bng 1 di y.Bng 1. Mt s c im hnh thi ca cc loi thuc ging Rhinopithecusc im Chiu di c th (mm) (thn v u) Chiu di ui (% chiu di thn v u) Mu lng lng Mu lng bng Mo lng trn nh u M Cc chi (tay v chn) Mt di i Dng vt Trng lng c th (kg)1 R. roxellana 680 760 110% Nu xm m Vng da cam nht Ngn Da cam Vng C mng lng sng mu 6,5 10,0 (ci) 15,0 39,0 (c) R. bieti 740 830 (ci) 830 (c) 70 90% Xm en Trng Di Trng en 9,2 (ci) 15,0 (c) R. brelichi 660 762 85 95% Nu xm Xm vng en en Mu sng 7,8 (ci) 13,3 15,8 (c) R. avunculus 540 (ci) 650 (c) 140 150% en Vng da cam Vng en en en 7,0 9,0 (ci) 13,0 16,0 (c)2

Ngun: Corbet v Hill (1992) [25]; 1 Kirkpatrick (1998) [51]; 2Phm Nht (1993) [8]

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1.3.3. Mt s c im sinh hc, sinh thiVng sng ca cc loi voc mi hch c kch thc t vi km2 ti hn 100 km2 v thay i theo mi loi [51, 91, 92]. Ging nh cc loi kh n l (colobine), cc loi voc mi hch thng sinh sng theo n vi kch thc n thay i ty loi. Kch thc n ca loi R. bieti c kch thc n l 9 269 c th/n [51, 92]; loi R. roxellana c kch thc n l 30 600 c th/n [51,92]; loi R. brelichi c kch thc n l 98 400 c th/n [51, 92]; v loi R. avunculus c kch thc n l 20 80 c th/n [19, 20]. Mt c th cng thay i ty loi, t 1 20 c th/km2 (Bng 2). Loi Voc mi hch (R. avunculus) hin c mt c th thp nht do cc nguyn nhn lm suy gim s lng qun th l: sn bn v mt sinh cnh [19, 20, 51, 92].Bng 2. Mt s c im sinh thi ca cc loi thuc ging Rhinopithecusc im cao (m so vi mc nc bin) Nhit trung bnh nm (oC) Vng sng (km2) Mt (c th/km2) Sinh cnh R. roxellana 2.200 2.800 6,3 28 55 1 15 Rng hn giao tre na, cy l kim v cy l rng ni cao R. bieti 3.000 4500 4,7 13 133 10 20 Rng thng xanh cy l rng v l kim n i ni cao R. brelichi 1.000 2.300 57 6,1 12,5 10 20 Rng thng xanh cy l rng v l kim cn nhit i ni cao R. avunculus 200 1.200 22,2 3,8 10 8 Rng nguyn sinh thng xanh trn ni vi v ni t

Ngun: Kirkpatrick (1998) [51]

T chc x hi ca cc loi voc mi hch n nay vn cha c nghin cu v hiu bit cn k. Mt s tc gi [19, 20, 51, 92] cho rng nhiu n v gia nh (family unit) kt hp vi nhau to thnh n ln (group/band). Mi quan h gia cc thnh vin trong gia nh voc v trong n ln nh th no n nay vn cha c bit r rng [51]. Thc n ca cc loi voc mi hch cng thay i ln theo mi loi. Voc mi hch (R. avunculus) n cc loi thc n t thc vt nh cc loi sung v (Ficus spp.), cc loi Polyathia v cc loi thuc h Thu du (Euphorbiacae) [7, 85]. Voc mi hch vng (R. roxellana) n cc loi l, chi non, qu v ht thay i theo ma r rt, vo ma ng ch yu l a y (41%), v cy (23%) v chi (22%) v

10

cc thi gian khc l qu (38%), a y (21%) v chi (17%) [63, 92, 97]. Voc mi hch Qu Chu (R. brelichi) n cc loi l, cung l, qu, ht v chi; thay i theo cc ma trong nm, t thng 01-03, chng n ch yu l chi (90%); trong thng 04-06, ch yu l cc loi l (93%); t thng 07-09, n ch yu l (58%), qu v ht (35%); v thng 10-12, n ch yn l non (47%), hoa (28%) v l (16%) [16]. Cc loi voc mi hch sng trn cy, hot ng v ban ngy. Voc mi hch (R. avunculus) c rt t hot ng trn mt t [33]. Tuy nhin, Voc mi hch Vn Nam (R. bieti) li dnh ti 22% thi gian hot ng v kim n ca chng trn mt t [65]. Cc kiu vn ng chnh ca voc mi hch l i bng bn chi (quadrupedal), leo tro (climbing), qung mnh v di chuyn bng hai chi trc (brachiate) [19, 20, 50, 92]. Cho n nay, ch c t kt qu v cng trnh khoa hc nghin cu v vn ng ca cc loi Voc mi hch ca mt s tc gi [19, 20, 33, 50, 65, 92].

1.3.4. Phn bCc loi voc mi hch thuc ging Rhinopithecus c vng phn b hp. Loi R. roxellana (Voc mi hch vng) c vng phn b rng nht, xut hin trong mt lot cc khu rng bit lp xung quanh ngoi vi ca vng h T Xuyn (cc tnh T Xuyn, Cam Tc, H Bc v Sn Ty). Loi R. brelichi (Voc mi hch Qu Chu) phn b gii hn trong mt qun th n l trn nh Phm Cnh Sn (tnh Qu Chu). Loi R. bieti (Voc mi hch Vn Nam) phn b ti 5 ht ca tnh Vn Nam v Ty Tng. Cui cng l loi R. avunculus (Voc mi hch) ch thy trong nhng khu rng vng ng-Bc Vit Nam [58, 89].

1.4. Vi nt v loi Voc mi hch (Rhinopithecus avunculus) 1.4.1. Tn gi- Tn khoa hc: Rhinopithecus avunculus Dollman, 1912 - Tn thng gi: Voc mi hch, Vc mi hch (Vit), Ca c, Tu cng (Ty), M pn (Dao)

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1.4.2. Phn loi hcDollman (1912) ln u tin m t loi Voc mi hch da trn 8 mu vt do Owston v Orii thu c ti tnh Yn Bi (2142' v Bc; 10453' kinh ng) vo thng 9/1911 [32]. ng so snh loi ny vi loi Voc mi hch Vn Nam (Rhinopithecus bieti Milne-Edwards, 1897) v cho l loi thuc ging Rhinopithecus. Pocock (1924) nhn thy c mt vi s khc nhau gia cc loi thuc ging Rhinopithecus v t li tn cho loi Voc mi hch bt c Yn Bi thuc ging Presbytiscus [86]. Thomas (1928) nghin cu 12 mu vt Voc mi hch do J. Delacour v H. P. Lowe thu c vo nm 1926 v 1927 v ng h kin ny ca Pocock [94]. S phn loi cc mu vt Voc mi hch ca Thomas c Ellerman v Morrison-Scott (1951) ng h, cc tc gi ny nhn thy cc loi voc mi hch Trung Hoa c nhng s khc bit vi loi Voc mi hch (R. avunculus) Vit Nam [35]. Jablonski v Peng (1993) phc hi ging Presbytiscus nh mt phn ging v cho rng Voc mi hch (R. [Presbytiscus] avunculus) khc vi cc loi voc mi hch khc cc c im: s thch nghi vi cch di chuyn trn cy, thn hnh thon th, t l gia cc chi v s lng hnh gii tnh gim [48]. Nhng c im ny tng t nh cc loi thuc ging Pygathrix. Cc tc gi ny cho rng nhng thch nghi c th l kt qu ca s ging nhau v mi trng gia hai ging Pygathrix v Rhinopithecus hoc ca mi quan h ging loi ca nhng ging c gi nh [48]. Nhiu nh nghin cu linh trng khng xem s khc bit ny l quan trng v nh vy mi quan h gia nhng loi voc mi hch vn cha c gii quyt, thm ch bng nhng nghin cu phn t [82, 101]. Phn ln cc nh phn loi hc v chuyn gia linh trng, hin nay, u tha nhn Voc mi hch (Rhinopithecus avunculus) thuc ging Rhinopithecus [21, 40, 46].

1.4.2. Mt s c im hnh thic im nhn bit: Thn hnh to ln. Lng vng b vai, mt ngoi ca cnh tay, lng v ng chn c mu nu sm n en. Mt trong ca cnh tay, bng

12

v ngc c mu vng nht hoc trng. Mt mu xanh da tri, mi mu hng. Mi hch rt c trng. ui di mu trng. Con non c b lng mu trng hoc xm nht, khi ln chuyn thnh mu en [1, 10]. Mt s ch s v kch thc v trng lng ca Voc mi hch c trnh by Bng 3 di y.Bng 3. Kch thc v trng lng ca Voc mi hch (Rhinopithecus avunculus)Ch s Chiu di thn-u (L) (mm) Chiu di ui (T) (mm) Chiu di bn chn sau (HF) (mm) Chiu cao tai (A) (mm) Trng lng (W) (kg) Con c (n = 3) 658,33 (640 670) 823,00 (820 850) 217,67 (210 223) 44,00 (43 45) 14,9 (13,0 16,0) Con ci (n = 7) 520,00 (484 565) 685,71 (660 725) 173,29 (150 190) 28,00 (12 40) 7,9 (7,0 9,0) Trung bnh (n = 10) 561,50 (484 670) 726,90 (660 850) 186,60 (150 223 32,80 (12 45) 10,2 (7,0 16,0)

Ngun: Phm Nht (1993) [8]

1.4.3. Mt s c im sinh hc, sinh thiVoc mi hch (R. avunculus) sng rng bn thng xanh v rng thng xanh t thp nhit i c cao 200 1.200 m so vi mc nc bin, trong khi cc loi khc ca Trung Hoa sng trong nhng khu rng ni n i c cao trn 1.200 m so vi mc nc bin [89]. Voc mi hch l loi hot ng ban ngy, sng trn cy v di chuyn bng bn chi (quadrupedal) v di chuyn bng chi trc khng hon ton (semibrachiation). Chng ng di nhng cnh cy thp. Trong khong thi gian c gi ma ng-Bc lnh, ngi ta tm thy ni ng ca chng gn cc sn ni dc ng [19, 20]. Thc n hng ngy ca Voc mi hch (R. avunculus) ch yu gm cc loi qu v l cy [7, 19, 20, 85]. Kt qu nghin cu thc n cha trong d dy cho thy loi ny ch yu n cc loi l cy, trong l cy a thch nht l tre [7]. Hn 60% thc n trong d dy ca hai c th ci c cha nhng mu tre [88]. Tuy nhin, nhng nghin cu sau ny cho thy Voc mi hch thng n cc loi qu nhiu hn [19, 20, 85].

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Boonratana v L Xun Cnh (1994) bng phng php ly mu lin tc (scan sampling) ca 34 lt quan st thnh phn thc n ca Voc mi hch t thng 9 nm 1993 n thng 2 nm 1994 KBTTN Na Hang (tnh Tuyn Quang) c tnh c khong 47% thc n hng ngy l qu xanh, 15% l ht qu chn, l non v cc phn ca l ch chim 38% [19]. Cn Phm Nht (1993) nhn xt khng c du vt no ca ng vt c tm thy trong cc d dy ca Voc mi hch [7]. Theo Boonratana v L Xun Cnh (1994), n v x hi c bn ca Voc mi hch l n v gia nh gm mt c th c trng thnh v cc c th ci trng thnh cng cc con ca chng hay cn gi l n v n c (One male unit OMU) vi trung bnh l 14,8 c th/nhm [19, 20]. Nhng c th c trng thnh v sp trng thnh khc to thnh nhng nhm cc c th c hay cn gi l n v ton c (all male unit AMU). Cha c cc quan st v nhng c th sng ring bit. Hai hoc nhiu n v x hi nh vy ca Voc mi hch thng di chuyn, kim n v ng cng nhau to thnh n ln [19, 20, 33]. Voc mi hch hot ng kh yn lng [88]. Chng thng pht ra nhng m thanh c trng ging nh ting nc hukkchukk cnh bo cho nhau, hoc thng tin cho nhau gia cc c th trong n hoc gia cc n vi nhau [19, 20]. Theo nhng ngi i sn a phng, khi mt con voc b bn, nhn chung c n khng b chy ngay m ngi bt ng v im lng. Tp tnh ny lm cho voc mi hch c bit d b nhng ngi i sn bn cht mt vi con trong vi ba pht [88]. Tp tnh sinh sn ca Voc mi hch cha c nghin cu. Theo Jablonski v Pan Ruliang (1995), s lng hnh gii tnh c bit v kch thc c th v cu to rng nanh nh l mt yu t nhng c th c cnh tranh bn tnh trong giao phi [47]. Trong s 4 loi voc mi hch, Voc mi hch (R. avunculus) t c s khc bit v lng hnh gii tnh nn c th t c s cnh tranh gia nhng c th c trong ma sinh sn [73].

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Voc mi hch sinh sng trn cy, di chuyn bng bn chn, leo tro v Di chuyn bng chi trc; him khi di chuyn trn hai chn sau v di chuyn trn mt t [19, 20, 33].

1.4.4. Phn bVoc mi hch (R. avunculus) l loi linh trng c hu ca vng ng Bc Vit Nam, phn b ti mt s khu rng thuc 05 tnh: H Giang, Tuyn Quang, Bc Kn, Thi Nguyn v Qung Ninh [73] (Bn 1). S lng qun th ca Voc mi hch, trn ton quc, hin c tnh khong 140-170 c th, tuy nhin, ch c 3 qun th c s lng hn 20 c th l: phn khu Tt K v phn khu Bn Bung ca Khu BTTN Na Hang (Tuyn Quang) v khu vc Khau Ca thuc tnh H Giang [56, 58, 61].

1.4.5. Cc mi e daSn bn tng din ra rt ph bin trn ton b vng phn b ca Voc mi hch. y cng l mi e da chnh v l nguyn nhn trc tip lm gim nghim trng s lng qun th ca loi ny. Kt qu ca nhng cuc iu tra c thc hin trong nm 1992 [88] v nm 1999 [29] cho thy t nht c 35 con voc mi hch b bn, trong giai on 1989 1999, nhng khu vc iu tra ti cc tnh Tuyn Quang, Bc Kn v Thi Nguyn. Kt qu iu tra ca ng Thanh Hi v cng s (2006) cho thy sn bt lm suy gim nghim trng s lng qun th Voc mi hch KBTTN Chm Chu (Tuyn Quang) [34]. Ngoi vic s dng tht Voc mi hch lm thc n, mt s b phn c th ca chng cn l nguyn liu ch nhng phng thuc cha bnh, nh: da c dng cha tr cc bnh ngoi da ca ngi [88]; bn chn, bn tay phi kh c dng nu sp iu tr suy nhc c th [29] hay dng nu cao [55, 56]. Suy gim sinh cnh do nn khai thc g din ra cc khu vc c tim nng cc loi g c gi tr cao, nh Nghin Excentrodendron tonkinense (Tiliaceae) khu vc Khau Ca (H Giang) v KBTTN Yn T (Qung Ninh) [56]. Hot ng khai thc g cng l nguy c tim tng tc ng ti s s dng sinh cnh ca

15

Bn 1. Phn b ca Voc mi hch (Rhinopithecus avunculus) Vit Nam (theo Nadler v cng s, 2003) [73] 16

Voc mi hch (R. avunculus). Mt khc, nhng ngi khai thc g c th sn bn cc c th Voc mi hch lm thc n trong sut thi gian khai thc g ca h. Vic khai thc g cng m ra cc li mn trong rng gip cho cc th sn c th d dng tip cn vi cc qun th Voc mi hch [29, 56, 58, 88]. Sinh cnh b tn ph do xy dng c s h tng v nh my thy in. Nh my Thy in Na Hang ang c xy dng khu vc lin k vi KBTTN Na Hang. Mc d, sinh cnh sng ca Voc mi hch khu bo tn ny hin cha b ph hy nhng nhng hot ng v sinh sng ca khong 5.000 cng nhn xy dng nh my (nm 2003 2004) tc ng n khu bo tn, d rng c khong 3.000 ngi dn a phng di di khi khu vc cng trnh [66]. Nn khai thc m cng l mt mi e da nghim trng i vi s ton vn sinh cnh sng ca loi Voc mi hch 2 tnh Tuyn Quang v Bc Kn. Hot ng ny rt ph bin trong nhng khu vc ni vi, ni m qun th Voc mi hch ln nht cn li xut hin. Nhng m thic v nhm c khai thc t nhiu thp k ti Bn Thi (huyn Ch n, tnh Bc Kn). Vic khai thc vng l mt hot ng khai thc ln trong khu vc Tt K ca KBTTN Na Hang (huyn N Hang, tnh Tuyn Quang). Mt khi qung c tm thy, do vic iu tra thm d mt din tch ln n 100 ha c th b pht quang. Hn na, cc hot ng khai thc cng lm gia tng s lng nhng ngi n cht g, ngi n ci v ngi i sn ti vng ny [29, 88].

1.4.6. Tnh trng bo tnTrong cun Sinh hc Bo tn Linh trng [Primate Conservation Biology], Cowlishaw v Dunbar (2000) ly Voc mi hch (R. avunculus) nh l mt v d in hnh ca cc loi linh trng ang b e da tuyt chng [27]. Hin nay, Voc mi hch c xp trong danh sch 25 loi linh trng nguy cp nht trn th gii [69]. Voc mi hch c tn trong Nhm IB (Cm tuyt i khai thc, sn bt, bun bn v s dng) ca Ngh nh s 32/2006/N-CP [8]; Sch Vit Nam

17

(2000) xp mc Nguy cp E [1], v Danh lc IUCN 2006 xp cp Cc k nguy cp Critically Endangered (CR) [43]. Voc mi hch l loi c quan tm v u tin bo tn ca nhiu chng trnh nghin cu v bo tn v ang thc hin nh: D n Bo tn Voc mi hch (TCP) ti cc KBTTN Na Hang v Chm Chu (tnh Tuyn Quang); D n Bo tn Voc mi hch H Giang.

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Chng 2 A IM, THI GIAN V PHNG PHP NGHIN CU2.1. a im nghin cu 2.1.1. L do la chn khu vc nghin cuChng ti la chn khu vc Khau Ca, tnh H Giang, nghin cu v nhng l do sau y: - Mt c th ca Voc mi hch khu vc Khau Ca l kh cao (khong 5 c th/km2) so vi cc khu vc khc Vit Nam. - Rng khu vc Khau Ca l khu rng nguyn sinh thng xanh trn ni vi, ang c bo v tt. - Qun th Voc mi hch v sinh cnh ca chng khu vc Khau Ca v ang c gim st v bo v tt, thun li cho vic theo di v quan st Voc mi hch trong qu trnh nghin cu. - Kt qu nghin cu cng gp phn cung cp cc thng tin lm c s khoa hc cho cc hot ng bo tn loi Voc mi hch trong khu vc nghin cu.

2.1.2. iu kin t nhin2.1.2.1. V tr a l Khau Ca l khu vc ni vi c din tch khong 1.000 ha, cch th x H Giang khong 15 km v pha ng v cch H Ni khong 300 km v pha Bc (Bn 2). Ta a l: 22o4938 22o5152 v Bc 105o0555 105o0912 kinh ng Khu vc Khau Ca nm trong a gii hnh chnh ca 3 x Tng B (huyn V Xuyn), Minh Sn v Yn nh (huyn Bc M), tnh H Giang: - Pha Bc thuc x Tng B.

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- Pha Nam thuc x Yn nh. - Pha ng thuc x Minh Sn. - Pha Ty thuc x Tng B v x Yn nh. Khu vc Khau Ca nm k bn KBTTN Du Gi (cch khong 5 km), tnh H Giang [14]. 2.1.2.2. a hnh Theo ti liu a cht, khu vc Khau Ca l khu vc ni vi in hnh. a hnh ca khu vc b chia ct mnh vi nhiu thung lng su v hp. nh ni cao nht ca khu vc l nh Cc mc, cao 1.341 m so vi mc nc bin cao gim dn theo hng Ty Ty bc v ng Bc, thp nht 466 m so vi mc nc bin (trung tm x Tng B). dc trung bnh l 30o [14].

Bn 2. V tr khu vc Khau Ca, tnh H Giang

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2.1.2.3. a cht v Th nhng a cht Khu vc Khau Ca nm trong vng c kin to a cht thuc k Tam, di tc ng ca nhit , nc, sinh vt v p sut cng vi s vn ng ca v Tri t, cc sn phm phong ha chia thnh hai dng trm tch [14] sau: - Trm tch ha hc: phylit phn b ri rc, din tch nh. - Trm tch c hc: sa thch chim t l ln v din tch > 85%, t hnh thnh t sa thch giu dinh dng, ti xp v thot nc. Th nhng Khu vc Khau Ca v cc vng ph cn c 3 nhm t chnh [14] sau: - Nhm t mn trn ni (H): t tt ph hp vi cc loi cy n qu, cy cng nghip, t giu, t l mn cao (3 5%). - Nhm t Feralit (F): l nhm t chnh cu thnh nn dng lp a ca khu vc ny, t l mn 1,5 2%, t ph hp vi cy lm nghip. - Nhm t thung lng (D): t tt ph hp cho cy nng nghip, t l mn ca loi t ny l 2,5 3%. 2.1.2.4. Kh hu v Thy vn Khu vc Khau Ca nm trong vng kh hu nhit i pha Bc, kh hu nng m v c ma ng kh lnh. Khu vc ny nm trong vng kh hu nhit i gi ma, thi gian nng nht trong nm l thng 7 8. Nhit Nhit trung bnh hng nm: 23,3 oC; Nhit cao nht: 37,5 oC (thng 01 nm 2005); Nhit thp nht: 7,5 oC (thng 07 nm 2004) (theo s liu ca Trm Kh tng H Giang, t thng 01/2004 n thng 09/2005; xem thm cc s liu sinh kh hu Biu 1 v Bng 4). Lng ma Tng lng ma: 2.300 mm/nm. Tng s ngy ma: 170 ngy/nm. S ngy khng ma lin tc di nht: 16 ngy (thng 12 nm 2004).

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Ma kh (vi lng ma < 100 mm/thng) ko di t thng 10 n thng 3 nm sau, v ma ma ko di t thng 4 n thng 9 (vi lng ma 100 mm/thng) (theo s liu ca Trm Kh tng H Giang, t thng 01/2004 n thng 09/2005; xem thm cc s liu sinh kh hu Biu 1 v Bng 4). m - m trung bnh: 83,9%. - m thp nht: 29% (thng 12 nm 2004). - S gi nng trong nm: 1.365 gi. Ton b khu vc nm trong khu vc thng ngun ca sng Gm (theo s liu ca Trm Kh tng H Giang, t thng 01/2004 n thng 09/2005; xem thm cc s liu sinh kh hu Biu 1 v Bng 4).

Biu 1. Biu sinh kh hu H Giang (cch Khau Ca 15 km)Ngun: Trn Khnh Vn v cng s (2000) [13]

Bng 4. S liu sinh kh hu Trm kh tng H Giang(ta : 22o49 v Bc; 104o59 kinh ng) Yu C Thng t nm 1 2 3 4 5 6 7 8 9 10 11 12 T 15,4 16,6 20,3 23,4 26,7 27,6 27,8 27,6 26,5 23,2 20,2 16,7 22,7 R 33,7 43,5 49,7 116,2 283,7 437,2 515,6 420,6 242,5 152,2 103,6 31,5 2430,1 T 6,5 6,2 6,6 7,1 7,9 7,9 8,3 8,6 8,3 8,0 7,5 7,5 7,6 U 85 84 83 82 84 85 86 84 83 84 85 85 84 S 1,9 1,9 2,1 3,7 5,3 5,4 5,6 4,4 4,2 3,6 2,9 2,9 3,8Ngun: Trn Khnh Vn v cng s (2000) [13] Ghi ch: T Nhit trung bnh; R Lng ma; T Bin dao ng nhit trung bnh; U m; S S gi nng

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2.1.2.5. Khu h thc vt Thm thc vt Kt qu iu tra ca Nguyn Anh c v cng s (2006) v Nguyn Ngha Thn v cng s (2006) xc nh cc kiu thm thc vt khu vc Khau Ca, tnh H Giang [78,81], l: - Rng thng xanh nguyn sinh ai ni thp trn ni vi: l kiu thm chnh trong vng vi din tch gn nh ton b tng s din tch rng ton khu h, phn b cao trn 700 m so vi mc nc bin. Rng gn nh gi c tnh nguyn sinh, gm hai phn kiu rng: + Phn kiu rng thng xanh hn giao cy l rng cy l kim nguyn sinh ai ni thp trn ni vi: phn b khu vc nh v gn nh ca cc ni vi. Tng cy g thp khong t 6 10 m duy nht v c u th bi cc loi: quyn Rhododendron spp. (Ericaceae), Hi Illicium spp. (Illiciaceae), Tru Vernicia spp. (Euphorbiaceae), Thch Acer spp. (Aceraceae), Chn chim Schefflera spp. (Araliaceae), Si Quecus sp (Fagaceae) v cc loi cy l kim cao hn 10m nh: Thng P c Pinus kwangtungensis (Pinaceae), Thng Taxus chinensis (Taxaceae), v.v.. Ngoi ra cn c nhiu loi c trng cho thc vt trn ging ni vi kh nng chu hn v gi tt l: cc loi ca h Thng tin Gesneriaceae, h Ci Cyperaceae, M h Mahonia nepalensis, h Anh tho Primulaceae v c bit l cc loi lan: Hi Vn Nam Paphiopedilum malipoense, Tin hi vng xanh Paphiopedilum hirsitissimu, Hi Henry Paphiopedilum henryanum (Orchidaceae). + Phn kiu rng thng xanh nguyn sinh cy l rng ai ni thp trn ni vi: phn b thung lng v chn ni, l kiu thm thc vt chnh trong khu vc, c trng bi cc cy g ln vi ng knh khong t 60 cm n hn 100 cm v chiu cao c th ln n 50 m nh: Nghin Excentrodendron tonkinense (Tiliaceae), Trai Garcinia spp. (Clusiaceae), Sng Pometia pinnata (Sapindaceae), v.v.. Tng tn cao t 20 n 35 m gm cc cy g

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kh ln, tn rng v an gn nh kn to nn mn rng vi che ph ti trn 80%: cc loi Th Diospyros spp. (Ebenaceae), Sng Pometia pinnata (Sapindaceae), Han voi Dendrocnide urentissima (Urticaceae), m balansa Bridelia balansae (Euphorbiaceae), v.v.. Tng di tn gm cc cy c chiu cao xp x 10m: Cc loi Nhc Polyalthia spp.(Annonaceae), Lng mang Pterospermum spp. (Sterculiaceae) Tng cy bi ch yu l cy con ca c tng cy g ln, tha tht (khong 20%). Tng thm ti cng tha tht nhng cng c cc loi c trng: Bng nc Impatiens sp. (Balsaminaceae), Thu hi ng Begonia spp. (Begoniaceae), Sam rng Elatostema spp. (Urticaceae), X cn Ophiorrhiza spp.,v.v.. Thc vt ngoi tng gm: cc loi b sinh k sinh nh: T iu Asplenium nidus (Aspleniaceae), i cn nam Macrosolen cochinchinensis, Mc v Trung Hoa Taxillus chinensis (Loranhthaceae) v cc loi thuc h Phong Lan Orchidaceae...; cc loi dy leo kh n diu nh: Dy b khai Erythropalum scandens (Olacaceae), h Thin l Asclepiadaceae, h Bu b Cucurbitaceae, h Nho Vitaceae, H Tit d Menispermaceae, - Rng thng xanh th sinh l rng ai ni thp trn ni vi: l trng thi suy thoi ca cc kiu trn hoc trng thi ti sinh sau nng ry. Cc loi c trng gm: Bp bc Mallotus spp., Si Triadica rotundifolia. (h Thu du Euphorbiaceae); B mm Pouzolzia sp. (h Gai Urticaceae), Lng mang Pterospermum spp., Sng Sterculia spp. (Sterculiaceae), cc loi Sung Ficus spp. (Moraceae). trng thi tc ng nng n hn hoc mi ti sinh sau nng ry c cc loi c trng: Ry Allocasia macrorrhiza, Chui Mussa sp., Rum Trung b Cecrospermum annamensis (Cecropiadaceae), M Clerodendron sp. (Verbenaceae), t Thysanolaena maxima, Ngy Rubus spp., n chu chu Aralia sp. Cc loi dy leo cng rt phong ph gm: Mc thng Iodes cirrhosa (Icacinaceae), cc loi thuc h Thin l Asclepiadaceae, h Nho (Vitaceae), h Ry (Araceae) v cc loi b sinh nh T iu Asplenium nidus (Aspleniaceae), Li mo tai chut Pyrrhosia lingua (Polypodiaceae)

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- Trng cy bi th sinh: Nm xen gia cc thung b tc ng do cc hot ng ca con ngi v cc chn ni vng tip gip gia vng m vi cc vng li. Cc loi c trng gm c: Mm xi Rubus alcaefolius, Ngy hng Rubus cochinchinensis v cc loi ngy khc thuc h hoa hng (Rosaceae); Mui thng Melastoma normale v mt s loi khc trong h Mua (Melastomataceae), cc loi C lo Chromolaena odorata (Asteraceae), C chit Thysanolaema maxima (Poaceae), K Urena lobata (Malvaceae), Gut Pteridium aquilinum (Pteridaceae). i khi trn cc trng bi ny cn xut hin cc cy g mc nhanh nh Bc bc Mallotus sp., M rng Macaranga sp. (Euphorbiaceae), B mm Pouzolzia (Urticaceae), Bi li Litsea sp. (Lauraceae), v.v.. Lnh ngnh Cratoxylon formosum (Clusiaceae). Cc loi dy leo, bi trn c: Kh o Thladiantha siamensis, Qua lu ba v Trichosanthes baviensis (Cucurbitaceae); Khoai lang di Ipomoea sp., Bc thau Merremia sp. (Convolvulaceae), n chu chu Aralia armata (Araliaceae) - Trng c th sinh: chim mt din tch rt nh trong khu vc, cc loi c trng nh: C tranh Imperata cylindrical (Poaceae), C sa l nh Euphorbia thymifolia (Euphorbiaceae), cc loi thuc chi M Plantago spp. (Plantaginaceae), n but Bidens pilosa (Asteraceae), Cc chn voi Elephantopus scaber cng vi nhiu loi khc trong h Cc (Asteraceae) - Thm nhn tc: l din tch t b ngi dn canh tc hoa mu ch yu l Ng Zea mays (Poaceae), ngoi ra mt s ngi dn trong vng cn tn dng t trong cc loi cy rau n v ly qu nh cc loi rau b Cucurbita spp. (Cucurbitaceae), hoc h b ging mt s loi cc cy ly g nh Xoan Melia azeadarach.. Thnh phn loi Kt qu iu tra ca Nguyn Anh c v cng s (2006) v Nguyn Ngha Thn v cng s (2006) ghi nhn c 471 loi thuc 269 chi, 113 h ca 4 ngnh thc vt bc cao c mch khu vc Khau Ca, tnh H Giang [78,81]. Trong , ch c 01 loi c tn trong Danh lc IUCN 2006 (IUCN, 2006), 13 loi c

25

tn trong Sch Vit Nam (B KHCN&MT, 2000) v 15 loi c tn trong cc ph lc ca Ngh nh s 32/2006/N CP. Chi tit c trnh by trong Bng 4.Bng 5. Danh sch cc loi thc vt qu him ghi nhn khu vc Khau CaSTT 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. H Berberidaceae Clusiaceae Flacourtiaceae Illiciaceae Lauraceae Lauraceae Lauraceae Meliaceae Menispermaceae Myrsinaceae Oleaceae Orchidaceae Orchidaceae Orchidaceae Orchidaceae Pinaceae Podocarpaceae Podocarpaceae Rubiaceae Taccaceae Taxaceae Taxaceae Tiliaceae Loi Mahonia nepalensis Garcinia fagraeoides Bennettiodendron cordatum Illicium parviflorum Cinnamomum burmannii C. loureirii C. magnificum Chukrasia tabularis Stephania rotunda Ardisia silvestris Meliantha suavis Paphiopedilum henryanum P. hirsulissimum P. malipoense P. micranthum Pinus kwangtungensis Nageia fleuryi Podocarpus neriifolius Rubia cordifolia Tacca integrifolia Amentotaxus argotaenia Taxus chinensis Excentrodendron tonkinense Tnh trng bo tn IUCN SVN N 32 VU V R R K V K T V T T R R V x x x x x x x x x x x x x x x

Ngun: Nguyen Anh Duc v cng s, 2006) [78] Ghi ch: - IUCN Danh lc IUCN 2006 (IUCN, 2006): VU Sp nguy cp; SVN Sch Vit Nam (B KHCN&MT, 2000): V Sp nguy cp, R HIm, K B e da thp, T Thiu thng tin; N 32 Ngh inh s 32/2006/N-CP: x c tn trong danh lc.

2.1.2.6. Khu h ng vt Cho n nay, cc nghin cu v khu h ng vt khu vc Khau Ca c thc hin ch yu l v khu h chim v th. Cc kt qu nghin cu thng k c 26 loi th thuc12 h, 6 b [57]; 99 loi chim thuc 23 h, 12 b [59]. Danh sch cc loi th qu him khu vc Khau Ca (H Giang) c trnh by Bng 5.

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Bng 6. Danh sch cc loi th qu him khu vc Khau CaSTT 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. Tn Vit Nam Cu li nh Cu li ln Kh mt Kh mc Voc mi hch Gu nga Gu ch Cy gm Cy ging Cy hng Cy vn Mo rng Sn dng T t vng Sc bay ln Sc bay b Tn khoa hc Nycticebus pygmaeus N. bengalensis Macaca arctoides M. assamensis Rhinopithecus avunculus Ursus thibetanus U. malayanus Prionodon pardicolor Viverra zibetha Viverricula indica Chrotogale owstoni Prionailurus bengalensis Naemorhedus sumatraensis Manis pentadactyla Petaurista philippensis Hylopetes spadiceus Tnh trng bo tn N 32 SVN IUCN IB V VU IB V VU IIB V VU IIB V VU IB E CR IB E VU IB E VU IIB R IIB IIB IIB V IB IB V VU IB V LRnt IIB R IIB R -

Ngun: L Khc Quyt v Lu Tng Bch, 2006 [57]Ghi ch: - Ngh nh 32 Ngh nh s 32/2006/N-CP: IB Nhm I. Nghim cm khai thc v s dng/IB. ng vt hoang d; IIB Nhm II. Hn ch khai thc v s dng/IIB. ng vt hoang d; SVN Sch Vit Nam (B KHCN&MT, 2000): E Nguy cp, V Sp nguy cp, R Him, T Thiu s liu; IUCN Danh lc IUCN 2006 (IUCN, 2006): EN Nguy cp, VU Sp nguy cp, LR t b e da, DD Thiu thng tin.

2.1.3. iu kin kinh t-x hi2.1.3.1. Dn s v Dn c Nm trong a gii hnh chnh ca 3 x Tng B (huyn V Xuyn), Yn nh v Minh Sn (huyn Bc M), tnh H Giang, khu vc Khau Ca chu nh hng trc tip v gin tip ca 16 thn bn sau: - 5 thn ca x Tng B: Hng Minh, Phc H, Nm Ra, Hng Tin v Khun Lng. - 5 thn ca x Minh Sn: N Sng, Khui La, Phia eng, Khui Kn v Lng Vy. - 6 thn ca x Yn nh: N X, Bn B, N Yn, Bc Bu, T M v Bn Loan. Theo s liu iu tra ca L Hng Mnh v Nguyn Hong Linh (2006), tnh n ngy 31 thng 12 nm 2004, tng s c 1.791 h vi 9.667 nhn khu, trong chim a s l dn tc Ty (chim 77,6%) v dn tc Dao (chim 15,2%), cn li l

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cc dn tc khc nh Hmng, Kinh (chim 7,2%). Chi tit v tnh hnh dn s v dn c ca khu vc Khau Ca c trnh by trong Bng 6. S liu Bng 6 cng cho thy, i sng dn c sng xung quanh khu vc Khau Ca cn thp. Trong tng s 1,791 h, s h ngho cn chim 34,9%, s h trung bnh l 57,7 % v s h giu l 7,4% [7]. T l tng dn s t nhin trung bnh ca khu vc, trong nm 2004, l 3,01%. 2.1.3.2. V nng nghip Trng trt v chn nui l hot ng kinh t ch yu ca nhn dn sng quanh khu vc Khau Ca. Ton b khu vc c tng s 784 ha t nng nghip, trung bnh 0,43 ha/h (xem chi tit trong Bng 8). Ngi dn a phng thu nhp ch yu t cc hot ng nh: trng trt bao gm la, ng v cc loi hoa mu khc, v chn nui tru, b, d, ln, gia cm v cc loi vt nui khc. Hot ng sn xut nng nghip trong khu vc cn gp nhiu kh khn v ph thuc vo cc iu kin t nhin: a hnh i ni dc, thi tit kh hu khc nghit. K thut canh tc ca dn a phng cn thp. Cng tc phng chng dch bnh v dch hi vt nui, cy trng cn nhiu hn ch. 2.1.3.3. V lm nghip Sn xut lm nghip trong khu vc cn cha c ch . Cng tc giao t, giao rng c trin khai nhng hiu qu cha r rng, hin ch c 832,6 ha t lm nghip c giao khon cho cc h gia nh, trung bnh 2,8 ha/h gia nh, nhng phn b khng ng u ti cc thn bn [7]. Thu nhp t ngh rng ca ngi dn a phng ch bng khong 12% so vi tng thu nhp nng nghip. Hu nh thu nhp t rng l khng bn vng, bao gm c khai thc g bn, khai thc g ci v khai thc lm sn ngoi g [7].

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Bng 7. Hin trng dn s v dn c ca khu vc Khau Ca, tnh H GiangST T I. 1 2 3 4 5 Cc thn Tng s h 244 239 130 325 246 1.184 34 34 12 42 81 203 92 34 70 68 54 86 404 1.791 Ngho (h) 164 49 60 123 81 477 6 15 0 12 14 47 3 11 46 5 12 24 101 625 Trung bnh (h) 76 128 109 175 161 649 26 17 10 25 65 143 49 18 19 61 40 54 241 1.033 Giu (h) 17 68 19 27 4 135 2 2 2 5 2 13 40 5 5 2 2 6 60 208 S lng nh tm 30 0 0 0 0 30 0 2 9 0 11 22 2 4 56 Tng s nhn khu 1.448 1.333 709 1.647 1.222 6.359 172 217 75 236 509 1.209 473 167 378 332 302 447 2.099 9.667 Ty (ngi) 1.156 1.221 671 1.393 1.222 5.663 120 120 473 116 372 332 2 425 1.720 7.503 Dao (ngi) 228 104 31 243 0 606 52 217 75 236 580 12 272 0 284 1.470 Hmng (ngi) 64 7 0 0 71 509 509 39 21 0 60 640 Khc (ngi) 8 11 19 0 6 7 22 35 54

X Tng B Hng Minh Phc H Nm Ra Hng Tin Khun Lng Tng II. X Minh Sn 1 N Sng 2 khui La 3 Phia eng 4 Khui Kn 5 Lng Vy Tng III. X Yn nh 1 N X 2 Bn B 3 N Yn 4 Bc Bu 5 T M 6 bn Loan Tng TNG S

Ngun: L Hng Mnh v Nguyn Hong Linh (2006) [7]

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2.1.3.4. C s h tng Tt c cc thn bn u c ng dn sinh n c trung tm thn. Mt s thn bn c h thng ng lin thn c b tng ha, to iu kin thun li cho vic i li trong khu vc (nh ti cc thn bn ca x Tng B). Tuy nhin, ti hai thn Khui La v Phia eng, x Minh Sn, do nm khu vc c a hnh cao v dc nn ng giao thng n hai bn ny cn ht sc kh khn. Hin ch c x Minh Sn c 1 ch nh v c hp theo phin (05 ngy/phin). Tuy nhin, ti cc thn bn ny vn c cc hot ng bun bn nh, l do t thng v mt s h gia nh thc hin. H thng in li quc gia tip cn c ti hu ht cc thn bn. Hin ch cn hai thn Khui La v Phia eng, thuc x Minh Sn, do nm khu vc ring bit v a hnh kh khn nn cha c s dng in li. Thng tin, lin lc ca khu vc cn rt hn ch. Ti mi x, ch c 01 trm bu in-vn ha x. y l trung tm lin lc thng tin v vn ha chnh ca dn c trong vng. Mi x u c 1 trm y t t ti khu vc trung tm x. C s h tng (nh, trm), trang thit bi v thuc men c u t nhiu nhng vn cn thiu thn so vi nhu cu khm cha bnh ca ngi dn a phng. Cc x u c trng trung hc c s v tiu hc, mi thn cng c cc lp hc tiu hc v mm non. i a s dn a phng c xa m ch, tr em c i hc y .

2.2. Thi gian nghin cuChng ti tin hnh nghin cu cc c im sinh hc, sinh thi ca loi Voc mi hch (R. avunculus) ti khu vc Khau Ca, tnh H Giang, t thng 12 nm 2004 n thng 05 nm 2006, trong : - Tng s ngy thc a l: 231 ngy - Tng s ngy quan st i tng nghin cu: 50 ngy - Tng s gi quan st i tng nghin cu: 113 gi.

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2.3. Phng php nghin cu2.3.1. Phng php iu tra theo tuyn Ti khu vc nghin cu, chng ti xc lp mt h thng tuyn iu tra (Bn 3). Tuyn iu tra c thit lp da trn cc li mn c sn hoc to mi i qua cc sinh cnh khc nhau. c bit, cc tuyn u i qua cc khu vc c Voc mi hch xut hin. Chiu di mi tuyn khong 3,5 5 km ty thuc vo a hnh ca mi tuyn. Trong qu trnh iu tra theo tuyn, Voc mi hch c pht hin v quan st bng mt thng, ng nhm, quay phim v chp nh (nu c th). Cc thng tin thu c trong qu trnh iu tra c ghi chp vo s tay thc a.

2.3.2. Phng php theo di i tng nghin cuMi khi bt gp n voc, chng ti theo di, thu thp cc thng tin v loi nh tp tnh x hi, kim n, s dng vng sng, v.v. Quan st bng mt thng v ng nhm Bushnell 7x50. Cc thng tin thu c trong qu trnh iu tra, quan st c ghi chp vo s tay thc a.

2.3.3. Phng php xc nh cc nhm tui/gii tnhXc nh tui v gii tnh ca Voc mi hch ch yu theo phng php ca National Research Council (U.S.) (1981) [76] v Barnett (1995) [15]; c tham kho thm phng php ca Davies (1984) [30], Boonratana (1993) [17] v theo hnh nh mu c sn.

2.3.4. Phng php iu tra thnh phn thc nQua quan st trc tip Voc mi hch ang n trn cy no s thu mu thc n (l, hoa, qu, v.v.) ca cy ; x l s b cc mu thc n ny bng cn 70o, p v sy kh tm thi ti thc a. Cc mu ny s c x l v lu tr Bo tng Thc vt, Khoa Sinh hc, Trng i hc KHTN HQGHN; v c Nguyn Ngha Thn nh loi vi s tr gip ca Nguyn Anh c. Cc phn ca cy b Voc mi hch n c xc nh theo phng php ca Davies (1984) [30] (Bng 8).

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Ngun: Nguyn i Trung/Vin NC C-KC

Bn 3. H thng tuyn iu tra v v tr cc tuyn iu tra thc vt khu vc Khau Ca, tnh H Giang 32

Bng 8. Bng xc nh cc phn ca cy b Voc mi hch nCc loi L trng thnh Cung l L non Hoa v n hoa Ht Qu chn Qu xanh c im nhn bit Cc loi l pht trin y Phn lin kt gia phin l v cnh cy Phn bit vi cc l trng thnh bi t nht 02 c im sau: kch thc nh hn, mu nht hn/ hn, cha dui thng, v.v.. M sinh sn; i hoa (calyx), trng hoa (corolla), v.v.. Mm (embryo) v l mm (cotyledons), nhng khng c v ht dy (thick testas) L non (carpel) v cc m bao quanh l non bao gm c v qu x (fibrous pericarp); c mu vng, , v.v.. v v qu mng hoc mm L non (carpel) v cc m bao quanh l non bao gm c v qu x (fibrous pericarp); c mu xanh, nht, v.v.. v v qu cngNgun: Davies, 1984 [30]

2.3.5. Phng php nghin cu vng sngV tr gp n voc s c xc nh bng my nh v Garmin GPSMAP 60C; sau , nh du trn bn a hnh (UTM) t l 1:10.000. Xc nh khong cch hot ng trong ngy v din tch vng sng ca Voc mi hch bng cc 100x100 m trn bn a hnh (Davies, 1984) [30].

2.3.6. Phng php nghin cu v cc kiu vn ng v t thQuan st v xc nh cc kiu t th v vn ng ca Voc mi hch theo phng php ca Hunt v cng s (1996) [41] v theo hnh nh c sn. Mi kiu t th hay vn ng ca Voc mi hch c m t bng li hoc trnh by bng cc hnh v n gin hoc nh chp.

2.3.7. Phng php nghin cu cu trc rngDo iu kin kh khn ca a hnh ni vi nn chng ti khng th s dng phng php tiu chun nghin cu v cu trc rng. Thay vo , chng ti s dng phng php nghin cu theo tuyn iu tra thc vt ca Husch v cng s, (1993) [42], Ganzhorn (2003) [38] v West (2004) [99]. Da theo bn a hnh v kho st tng th khu vc nghin cu, chng ti xc lp 4 tuyn iu tra thc vt, mi tuyn di 1 km v rng 4 m.. Cc tuyn iu tra thc vt ny m bo tnh c trng ca cc sinh cnh ca khu vc Khau Ca (Bn 3).

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Chng ti cng tin hnh thu mu, o c, nh s v gn nhn tt c cc cy c DBH 10 cm thuc phm vi ca 4 tuyn (s liu c ghi theo Mu 3 ca Ph lc 3); cc mu c Nguyn Anh c v V Anh Ti nh tn ti Bo tng Thc vt, Khoa Sinh hc, Trng i hc KHTN HQGHN .

2.3.8. Phng php theo di vt huTt c cc cy nm trong phm vi ca 4 tuyn iu tra thc vt c theo di, nh gi 02 ln/thng, t thng 12 nm 2005 n thng 10 nm 2006. Cc s liu vt hu c thu thp v ghi vo phiu theo di vt hu (Ph lc 3).

2.3.9. Phng php phn tch s liuCc s liu thu c nhp, lu gi v phn tch bng my tnh xch tay HP Pavilion ze4900, vi cc chng trnh thng dng nh: Word, Excel, v.v.. Cc s liu c phn tch v thng k s liu bng chng trnh SPSS 13.0. Cc bn c x l v chnh sa bng chng trnh MapInfo 8.0SCP.

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Chng 3 KT QU NGHIN CU V THO LUN3.1. Qun th Voc mi hch khu vc Khau Ca 3.1.1. S lng qun thCn c vo s ln bt gp, quan st v s lng ca cc n Voc mi hch, trong qu trnh nghin cu, chng ti xc nh c khu vc Khau Ca (H Giang) c khong 53-60 c th Voc mi hch (Ph lc 4). ng Thanh Hi v Boonratana (2006) c tnh c 81-90 c th Voc mi hch khu vc ny [33]. Tuy nhin, theo cc tc gi ny, s liu c da trn kt qu ca 01 ln quan st, m v c tnh. Do , con s ny cn kim chng thm bng nhiu ln quan st v m khc. Tng hp s liu v s lng Voc mi hch 4 khu vc thuc 2 tnh Tuyn Quang v H Giang, t nm 1993 n nm 2006, (Bng 9) cho thy khu vc Khau Ca (H Giang) l ni c s lng Voc mi hch ln nht. iu ny chng t khu vc Khau Ca (H Giang) c tm quan trng quc gia v quc t trong cng tc bo tn loi Voc mi hch (R. avunculus) qu him ny.Bng 9. S lng qun th ca Voc mi hch cc khu vc phn b khc nhauSTT 1. 2. a im Khu vc Khau Ca (H Giang) Phn khu Tt K, KBTTN Na Hang (Tuyn Quang) Nm 2006 20061 19932 19983 20044 20051 19932 19995 20051 20016 20067 S lng Xc nh c on 53 60 81 90 72 80 13 16 40 17 22 23 50 40 45 50 8 70 0 8-12

3.

Phn khu Bn Bung, KBTTN Na Hang (Tuyn Quang) KBTTN Chm Chu (Tuyn Quang)

4.

Ngun: 1 theo ng Thanh Hi v Boonratanaa, 2006; 2 theo Boonratana v L Xun Cnh, 1994; 3 theo Boonratana, 1999; 4 theo Wolter, 2004; 5 theo Nguyen Xuan Dang v Nguyen Truong Son, 1999; 6 theo Long v L Khc Quyt, 2001; 7 theo ng Thanh Hi v cng s, 2006

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3.1.2. Kch thc v cu trc n khu vc Khau Ca (H Giang), chng ti xc nh v c tnh c khong 53 60 c th Voc mi hch, sng theo 3 n, mi n c 13 37 c th, trung bnh 16,2 c th/n (s ln quan st: n = 50, s lng c th/n: r = 3 37). Ngy 01 thng 01 nm 2005, chng ti quan st c n Voc mi hch c 37 c th (ti im B700: UTM 48Q 512446; 2526270). y l n voc c s lng ng nht. 2 n khc nh hn c khong 7 13 c th. Mi n thng c 2 c trng thnh, 3 ci trng thnh, 6 cha trng thnh loi 2, 5 cha trng thnh loi 1, 3 con non loi 2 v 2 con non loi 1 (Ph lc 4). Theo kt qu nghin cu ca Phm Nht (1993), Lc Yn (Yn Bi), Ch n (Bc Kn) v Na Hang (Tuyn Quang), Voc mi hch c kch thc trung bnh ca mt n Voc mi hch l 14,5 c th (n = 5, r = 7 25) [9]. Kt qu nghin cu ca ng Thanh Hi v Boonratana (2006), khu vc Khau Ca (H Giang), cng cho thy kch thc trung bnh ca mt n Voc mi hch l 12,1 c th (n = 14, r = 5 14) [33]. Theo kt qu nghin cu ca Boonratana v L Xun Cnh (1994), Na Hang (Tuyn Quang), kch thc n ca Voc mi hch KBTTN Na Hang, tnh Tuyn Quang, l 15,2 c th (n = 5, r = 10 24) [19, 20]. Nh vy, kch thc n Voc mi hch khu vc Khau Ca (H Giang) m chng ti xc nh c, tuy c ln hn so vi kch thc ca cc n Voc mi hch sinh sng cc khu vc khc, nhng s khc bit l khng ln lm.

3.1.3. T chc nChng ti xc nh c ba (03) n Voc mi hch khu vc Khau Ca (H Giang), t chc n theo 02 hnh thi sau: - Vi hai (02) n c kch thc nh (7 13 c th/n), t chc n thng gm 1 c trng thnh, 2 3 ci trng thnh, 2 3 cha trng thnh v 1 2 con non. y l hnh thi t chc n gm mt c th c trng thnh v cc c th ci trng thnh cng cc con ca chng hay cn gi l n v n c (One male unit OMU).

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- Vi n c kch thc ln ( 20 c th), t chc n thng gm 3 4 c trng thnh, 5 10 ci trng thnh, 3 5 cha trng thnh loi 2, 3 5 cha trng thnh loi 1, 2 4 con non loi 2, 1 5 con non loi 1. y l hnh thi t chc n c hnh thnh t nhiu n v n c (OMU) to thnh n ln (band). Cc c th trong n ln ny di chuyn, kim n v ng cng nhau. Tuy nhin, cc nhm nh (c th l mt gia nh) thng hot ng c lp vi nhau. Hin tng ny thng thy khi chng ngh ngi vo thi gian gia tra. - Trong sut thi gian nghin cu khu vc Khau Ca (H Giang), cha ghi nhn c cc n v ton c (all male unit AMU). S liu nghin cu nu trn cho thy t l gii tnh c:ci ca cc n Voc mi hch khu vc Khau Ca l khng cn i, t l ny l 1 c:2 ci 1 c:4 ci. Theo Fleagle (1999), cu trc n ca mt loi linh trng, trc ht l cc loi voc, c trng bi: kch thc v thnh phn ca cc n m cc c th linh trng thc hin cc hot ng hng ngy; t chc n ca mt s loi linh trng c nhiu mc (multilevel social organization); nhiu n nh cng di chuyn v hot ng to thnh n ln (band) [36]. Trong nhiu nghin cu v cc loi voc chu , Kirkpatrick (2007) cho rng kiu hnh ca cc nhm a gii tnh (mixed-sex groups) ca cc loi voc chu (Asian colobines) l n v n c (OMU) v mt s loi, cc n v n c (OMU) thng c vng sng chng ln nn thng to ra n ln (band) y l mc t chc x hi th cp (second level of social organization) [52]. T chc n Voc mi hch khu vc Na Hang (Tuyn Quang) cng c hnh thi nh vy [19, 20] v ging vi t chc n ca cc loi voc mi hch Trung Hoa (R. roxellana, R. brelichi v R. bieti) [16, 49, 50, 89, 92]. Nh vy, kt qu nghin cu t chc n Voc mi hch khu vc Khau Ca (H Giang) ca chng ti ph hp vi nhn nh ca Boonratana v L Xun Cnh (1994,1998) [19,20], Fleagle (1999) [36] v Kirkpatrick (2007) [52] nh ni trn.

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3.1.4. Mt s c im hnh thi theo cc nhm tui v gii tnhCn c vo nhng quan st trc tip v hnh nh ghi nhn c, chng ti xc nh mt s c im hnh thi ca Voc mi hch theo cc nhm tui v gii tnh nh sau: - Con c / Trng thnh: Mu lng en xen ln trng bn hoc trng sch; da mt v quanh mt mu xanh lc; mi hng, to v dy; vng c mu vng da cam; ui to, trng, c lng x v di hn 1,5 di thn-u; bu di mu sng, dng vt mu en. Trng lng: 15 22 kg. Hay i cng con ci trng thnh v mt s con nh loi 1 v con non, c bit l cc con ci c con non. - Con ci / Trng thnh: Mu lng en hoc xm en xen ln vi cc mnh lng mu trng hoc trng bn; da mt v quanh mt xanh en hoc xm en; mi to, hng nht; c mu vng da cam; ui di 1,5 di thn-u, lng ui ngn v khng x; nm v to v en hoc bng cha to. Trng lng: 8 13 kg. Thng m con non hoc c con nh i cng. - Cha trng thnh loi 2: B lng mu en, xm en hay en nht; da mt v quanh mt xanh nht v xm en; c mu vng da cam nht; mi hng nht; ui mu en xen ln trng. Kim n c lp; kim n v di chuyn theo n. - Cha trng thnh loi 1: Mu en nht, xm nht xen ln trng bn hoc vng nht; da mt v quanh mt mu xanh nht; mi nh, pht hng hay sng mu; ui di hn thn, mu en xen ln trng. Thng kim n v di chuyn bn cnh cc con ci hoc c trng thnh. - Con non loi 2: B lng mu trng bn xen ln nhng mnh lng mu en hoc xm en ln lng, cnh tay v i; da mt v quanh mt c mu m; ui mu trng. Vn cn b m hon ton; cha bit kim n, nhng c th t chi quanh m. Lun c con m m di bng khi di chuyn. - Con non loi 1: B lng mu trng hoc trng nh; da mt mu hng nht. B m hon ton; Lun c con m m di bng trong khi kim n v di chuyn.

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3.2. Mt s tp tnh ca Voc mi hch 3.2.1. Kim n (Feeding)Thc n a thch ca Voc mi hch khu vc Khau Ca (H Giang) l cung l, l non, hoa v qu nn Voc mi hch kim n ch yu trn cc tn cy. Vi cc loi thc n l thc vt dy leo, Voc mi hch thng chn nhng v tr thun li hoc u bm trn cc dy leo ny ly thc n, nht l khi chng n cung l v qu chn ca cy T qu Senguin Iodes senguini v qu ca cc loi T th Tetrastigma spp. Khu vc kim n ca Voc mi hch thay i ph thuc vo s phn b ca ngun thc n, thng cc khu thung lng v sn ni. Khi tm thy loi thc n a thch, nh qu chn ca cy T qu Senguin Iodes senguini, u rng Brassaiopsis spp. v Trai Garcinia spp., Voc mi hch thng dnh thi gian n cung l hoc qu (nu c) ca nhng cy ny sau mi chuyn sang n cc dng thc n khc. Thi gian kim n ca Voc mi hch bt u t khi chng thc dy khong 5:30 (ngy 27 thng 05 nm 2006), n khong 10:30-11:00 chng ngh tra v tip tc kim n t khong 14:30 n khong 17:30 (ngy 21 thng 05 nm 2005). Khng thy c s tranh chp v thc n gia cc c th trong n trong khi kim n. Voc mi hch thng ngi trn cnh cy v cc c th trong n/nhm phn tn theo trt t nht nh. Con c, con ci trng thnh v con non thng kim n gn nhau, khong cch gia cc c th l 1-3 m v gn nh trung tm khu vc kim n cn cc con cha trng thnh phn tn ra phn ra ca khu vc kim n.

3.2.2. Tp tnh x hi (Social behaviour)Tp tnh x hi ca Voc mi hch th hin r nht tp tnh sng theo n, quan h gia cc c th vi nhau qua: chi lng cho nhau (Affiliative grooming), chi a (Playing) v cnh gii (Safeguarding).

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- Chi lng cho nhau (Affiliative grooming): thng din ra tng cp: c th c trng thnh v c th ci trng thnh, c th m chi lng cho con non, c th ci trng thnh chi lng cho c th cha trng thnh v ngc li, cc c th cha trng thnh chi lng cho nhau. Phn ln, vic chi lng cho nhau thng din ra trong cc khong thi gian ngh ngi ca chng. - Chi a (Playing): thng din ra gia cc con non vi nhau hoc gia con non vi con cha trng thnh loi 1. Nh vy, chi a ch din ra gia cc c th non. C c th ny thng chi a vi nhau theo kiu ui bt hoc gi nh nhau. Cha c ghi nhn v s chi a gia cc c th trng thnh, gia c th trng thnh v c th cha trng thnh, gia c th trng thnh v con non, v gia cc c th cha trng thnh vi nhau. - Cnh gii (Safeguarding): Cha c ghi nhn v nhng c th lm nhim v cnh gii chuyn trch trong mt n Voc mi hch khu vc Khau Ca, tnh H Giang. Dng nh hu ht cc c th trong n, tr cc con non, u lm nhim v cnh gii. Do b sn bn trong sut thi gian di trc y, Voc mi hch khu vc Khau Ca rt nhy cm vi s hin din ca con ngi. Khi mt c th trong n pht hin ra ngi, n tm dng hot ng ring ca bn thn (nh hi, lm hoc ngng n, v.v.), ngi im v theo di hot ng ca con ngi, ng thi pht ra nhng ting ku bo ng cho c n. Nu khong cch cn xa (khong hn 30 m) th chng thng pht ra nhng ting ku nh ting nc kh hudkk chockk; nu khong cch gn (khong 10-30m), nhng ting nc hudkk chockk ny to v r hn. Trong mt s trng hp Voc mi hch thy ngi quan st khng di ng,nh 1. Voc mi hch th hin s da nt khi nhn thy vt th l (con ngi)

40

ng yn ti ch th con c trng thnh v mt s con khc c th tin li gn v cng pht ra nhng ting nc ny, h rng ming v nhn ngi. Hin tng ny dng nh l mt biu hin e da i vi i tng m chng ang theo di (nh 1).

3.2.3. Ngh ngi (Resting)Voc mi hch thng ngh ngi vo gia cc khong thi gian di chuyn v kim n; ban m voc ng. Thi gian ngh ngi ca Voc mi hch ch yu vo bui tra (t 10:30 n 14:30). Nu khng b quy ry, chng dnh thi gian ny ngi ngh trn cc cnh ln trong tn cy. Voc mi hch thng ngh theo tng c th n l hay nhm (c th l mt (01) gia nh, gm mt c th c trng thnh, mt c th ci trng thnh, mt vi c th cha trng thnh v con non). Trong thi gian ngh, Voc mi hch c th: ngi ngh, khng hot ng, c khi ng chp mt v c c th t chi lng (auto grooming) hoc chi lng cho nhau (affiliative grooming).

3.2.4. Di chuyn (Traveling)Voc mi hch sng trn cy v hot ng ban ngy; rt him khi xung t. Tuy nhin, trong khu rng trng, cc cy rng cch xa nhau, Voc mi hch c th xung t di chuyn t cy ny sang cy khc. Hin tng ny quan st c vo hi 15:40, ngy 16 thng 01 nm 2006 ti im B300 (Ta : UTM 48Q 512082; 2526179). Chng ch xung t trong trng hp khng b kinh ng. Nu b kinh ng, Voc mi hch lp tc chy ti v tro ln cy, sau chng tip tc di chuyn trn cy. Khi di chuyn trn cy, voc b hoc bm t cnh cy ny sang cnh cy khc. Khi i qua mt cnh cy ln hoc chuyn gia hai cy, nhiu c th Voc mi hch c kiu di chuyn hng mt, con i sau ni ui con i trc.

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3.3. Mt s c im sinh thi dinh dng 3.3.1. Thnh phn thc nKt qu nghin cu t thng 12 nm 2004 n thng 05 nm 2006, khu vc Khau Ca (H Giang), chng ti xc nh c 32 loi thc vt thuc 21 h l thc n ca Voc mi hch (Bng 10). Trong , h Ng gia b (Araliaceae) c 4 loi; h Ba (Clusiaceae), h Thu du (Euphorbiaceae) v h Long no (Lauraceae) mi h c 3 loi; h Trc o (Apocynaceae) v h Nho (Vitaceae) mi h c 02 loi; cc h thc vt cn li ch c 1 loi. Voc mi hch n cc b phn khc nhau ca cy, trong cung l c n nhiu nht (26,32%), qu xanh (23,68%), qu chn (21,05%), l non (10,53%), ht (7,89%) v cc b phn khc (10,53%) bao gm hoa, li cnh v l trng thnh chim t l nh trong khu phn thc n ca voc. Cha c ghi nhn Voc mi hch bt v n thc n ng vt (Biu 2). Cc loi qu Voc mi hch a thch gm c u rng Brassaiopsis spp., Nghin Excentrodendron tonkinense, T qu Senguin Iodes seguini v cc loi Trai Garcinia spp.L non 10.53% Qu chn 21.05% Ht 7.89%

Hoa 5.26% L trng thnh 2.63% Li cnh 2.63%

Qu xanh 23.68% Cung l 26.32%

Biu 2. Thnh phn thc n ca Voc mi hch khu vc Khau Ca, tnh H Giang (n = 38)

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Bng 10. Danh sch cc loi thc vt l thc n ca Voc mi hch Khau CaSTT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Tn Vit Nam H Thch Thch Bc b H Trc o Giom Tourner Trc o (?) H Ng gia b u rng u rng (?) Chn chim my Chn chim l nh H Thin l Thin l (?) H Nc nc R t H Ba Trai l Trai thng Trai H Th My rc H Thu du Chi mi m lm Si ta H D Sa H Long no Bi li Ba V Bi li Tn khoa hc Aceraceae Acer tonkinensis Apocynaceae Melodinus tourneri Apocynaceae sp. Araliaceae Brassaiopsis stellata Brassaioopsis sp. Schefflera aff. velunosa Schefflera palmiformis Asclepiadaceae Goniostemma punctatum Bignoniaceae Rhadermachera sp. Clusiaceae Garcinia bracteata Garcinia fagraeoides Garcinia sp. Ebenaceae Diospyros sp. Euphorbiaceae Antidesma sp. Bridelia retusa Sapium rotundifolium Fabaceae Dalbergia tonkinensis Lauraceae Litsea baviensis Litsea sp. Dng sng GoTB LeoGo Leo GoNho GoNho LeoGo LeoGo Leo GoLon GoLon GoLon GoLon GoLon GoLon GoLon GoLon GoTB GoNho GoNho B phn b n CL QX CL QC QC LC CL CL H CL, QC CL, QC CL, QC LN, LN QC Ht QC Qx QX QX QX LN Q Ht Q CL CL CL CL CL CL CL CL CL H CL CL H CL CL CL H, LN H CL CL CL LN CL CL CL CL CL CL CL CL CL CL CL CL CL, Q CL, Q CL, Q CL, Q CL, Q CL, Q CL CL CL 1 CL 2 CL 3 CL 4 5 6 Thng 7 8 9 10 11 CL 12 CL QX CL Q Q LC LC CL Q CL CL CL CL Q

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Bng 10 (tip theo)STT 20 21 22 23 24 25 26 27 28 29 30 31 32 Tn Vit Nam Kho H Th o T qu Sengui H Trinh n Ct nga H Du tm Sung H Nhi Nhi (?) H Lan Cu dip gn H Mt x Mt x Ford H B hn Sng H Hng xim Sn t Trung Hoa H ay Nghin H Nho T th dng O liu Khau tp H Gai Ch pan Tn khoa hc Lauraceae sp. Icacinaceae Iodes seguini Mimosaceae Archidendron sp. Moraceae Ficus sp. Oleaceae Olea sp. Orchidaceae Bulbophyllum affine Sabiaceae Meliosma fordii Sapindaceae Pometia pinnata Sapotaceae Sinosideroxylon wrightianum Tiliaceae Excentrodendron tonkinense Vitaceae Tetrastigma oliviforme Tetrastigma sp. Urticaceae Debregeasia squamata aff. etuberculata Dng sng GoLon LeoGo GoLon BiSi GoTB BiSi GoTB GoLon GoLon GoLon Leo Leo GoNho B phn b n QX CL,QC Ht LN QX L CL QC,QX CL QX, H QX QX LN QX QX LN QX LN H H Qx CL Q Q QX Qx Q Q CL CL L LN 1 2 3 4 5 Thng 6 QX CL, Q Ht 7 8 9 10 11 12

CL

CL

CL

CL

CL, Q Ht

CL Ht

CL

CL

CL

CL

CL

Ghi ch: - GoLon Cy g ln, GoTB Cy g trung bnh, GoNho cy g nh, Leo Dy leo, LeoGo Dy leo thn g, BiSi Cy b sinh - CL Cung l, L L trng thnh, LN L non, H Hoa, Q Qu chn, QX Qu xanh, Ht Ht, LC Li cnh

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Biu 2 cho thy cung l l thc n ch yu (chim 26,32%) ca Voc mi hch khu vc Khau Ca (H Giang). Tuy nhin, vo thi gian t thng 06 n thng 10, voc t n cung l v khi Khau Ca qu ca nhiu cy l thc n ca voc gi v chn. Theo L Hin Ho (1973), thc n ca Voc mi hch rt a dng, thng gp nht l cc loi Sung Ficus spp., cc loi Ba Garcinia spp. v c mng ca cc loi tre na (Poaceae) [4]. Kt qu nghin cu ca Boonratana v L Xun Cnh (1994,1998) cho thy Voc mi hch n cc loi l non (38%), qu xanh (47%), ht v qu chn (15%), c bit xc nh Voc mi hch n ht t qu chn ca loi S Vidan Beilschmiedia aff. vidalli Kost. (Lauraceae) [19, 20]. Tuy nhin, cc tc gi ny khng a ra danh lc thc n ca Voc mi hch. Phm Nht (1993, 1994) thng k cc b phn cy ca 52 loi thuc 18 h thc vt l thc n ca Voc mi hch [7, 85]. Tuy nhin, do tc gi c s dng phng php phng vn dn a phng v thc n nui nht trong thi gian ngn, nn nhiu loi trong s ny khng c phn b khu vc sng ca Voc mi hch. ng Thanh Hi cng ghi nhn c 14 loi thuc 11 h thc vt l thc n ca Voc mi hch khu vc Khau Ca (H Giang) ( dn trong ti liu [61]). T nhng kt qu nghin cu ca cc tc gi nu trn cng vi kt qu nghin cu khu vc Khau Ca, chng ti xc nh c 54 loi thc vt c th l thc n ca Voc mi hch (Ph lc 5). So snh gia s thay i thc n ca Voc mi hch theo cc thng vi s thay i v vt hu hc (phonological monitoring) ca tt c 1.103 cy c trn 4 tuyn iu tra thc vt khu vc Khau Ca (H Giang) cho thy thc n ca Voc mi hch cng thay i cng vi nhng s thay i ca cy rng. T thng 03 n thng 05, Voc mi hch n cc loi l non v hoa nhiu hn do cng thi gian ny cy rng cng c nhiu l non v hoa. Tng t, t thng 08 n thng 10, Voc mi hch n nhiu qu chn hn do thi gian ny nhiu cy rng c qu chn (Biu 3).

45

T l (%)100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 1 2 3Cung l

4L non

5

6

7Qu chn

8Qu xanh

9Hoa Ht

10Li cnh

11

L trng thnh

12 Thng

Biu 3. S thay i thc n theo ma ca Voc mi hch khu vc Khau Ca, tnh H GiangS cy12001092 1,076 1,072 1,093 1,054 992 1,046 1,095 1,099 1,090 1,089

1000

800692 620

600

401

411 349

400301 222

323

214 144 74 1 3 76 41 2 8 7 2 47 16 4 2 13 5 3 11 2 17 5 2 17 92 102 86

200

183

54 6 12 1 30 7 19 28 4 9 23 4 12 25 2 6

58

56 56

0 12 2005L trng thnh L non Hoa

1

2

3

4

5 2006

6

7

8

9

10

ThngQu chn Qu xanh

N hoa

Biu 4. S thay i theo ma ca cc loi thc vt khu vc Khau Ca, tnh H Giang (n = 1.103)

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Kt qu theo di vt hu ca 1.103 cy trn 4 tuyn iu tra thc vt, t thng 12 nm 2005 n thng 10 nm 2006, cho thy s cy c l trng thnh lun c t l cao nht (89,89 99,27% tng s cy) trong sut thi gian theo di; iu chng t khu rng Khau Ca l rng thng xanh. S cy c l non c t l kh cao (13,06 62,69%), t thng 3 n thng 6; t l s cy c l non cao nht (62,69%) trng vi thng 05. S cy c hoa (0,45 5,21%) v n hoa (0,14 6,71%) xut hin vi t l thp. S cy c qu chn (0,09 1,54%) v qu xanh (0,27 9,25%) cng c t l thp v xut hin trong sut thi gian theo di (Biu 4). Tuy nhin, y mi ch l nhng ghi nhn ban u v thc n ca Voc mi hch trong t nhin khu vc Khau Ca, tnh H Giang. Cn c thm cc nghin cu chuyn su hn c th hiu r v thnh phn thc n v s thay i theo thi gian (trong ngy v ma) ca Voc mi hch khu vc ny.

3.3.2. Ngun thc nTrong s 48 h thc vt trn 4 tuyn iu tra thc vt khu vc Khau Ca (H Giang), c 21 h (chim 46%) c loi cy l thc n ca Voc mi hch (Bng 11). S cy thuc 21 h thc vt ny l 738 cy (chim 67%) trong tng s 1103 cy trn c 4 tuyn iu tra. Xem xt theo cc chi thc vt c th thy trong s 93 chi c trn c 4 tuyn iu tra thc vt c 12 chi (chim 13% tng s chi thc vt), vi 332 cy (chim 30,09% tng s cy) l thc n ca Voc mi hch. Trong s 1103 cy ca 149 loi thuc 4 tuyn iu tra thc vt, c 385 cy (chim 34,90% tng s cy v 44,22% tng tit din) ca 16 loi (chim 10,74% tng s loi) l nhng loi cy thc n ca Voc mi hch (Bng 11). ng ch , mt s loi thc vt l thc n ca Voc mi hch l nhng loi ph bin khu vc nghin cu nh Nghin Excentrodendron tonkinense (Tiliaceae), Trai Garcinia spp. (Clusiaceae), Olea sp. (Oleacceae) v Diospyros spp. (Ebenaceae). Loi T qu Senguin Iodes seguini (Icacinaceae) l mt trong nhng loi cung cp thc n chnh ca Voc mi hch cng l loi ph bin khu vc Khau Ca, tnh H Giang.

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Bng 11. S lng cc loi thuc cc tuyn iu tra thc vt l thc n ca Voc mi hch khu vc Khau Ca, tnh H GiangSTT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 H Aceraceae Araliaceae Bignoniaceae Clusiaceae Clusiaceae Clusiaceae Ebenaceae Euphorbiaceae Icacinaceae Lauraceae Mimosaceae Moraceae Oleaceae Sapindaceae Sapotaceae Tiliaceae Loi S cy % Tng s Tit din %Tit din Acer tonkinensis 15 1,36% 9.191,17 0,80% Brasaiopsis sp. 1 0,09% 107,46 0,01% Radermachera sp. 9 0,82% 10.273,64 0,90% Garcinia bracteata 22 1,99% 8.618,37 0,75% Garcinia paucinervis 7 0,63% 9.345,62 0,81% Garcinia sp. 30 2,72% 6.059,57 0,53% Diospyros spp. 69 6,26% 83.428,72 7,28% Antidesma sp. 10 0,91% 2.593,53 0,23% Gomphandra tetrandra 15 1,36% 5.535,44 0,48% Litsea spp. 51 4,62% 48.666,36 4,24% Archidendron sp. 3 0,27% 2.642,95 0,23% Ficus sp. 4 0,36% 7.341,53 0,64% Olea sp. 78 7,07% 23.414,23 2,04% Pometia pinnata 12 1,09% 28.594,29 2,49% Sinosideroxylon wightianum 10 0,91% 4.597,89 0,40% Excentrodendron tonkinese 49 4,44% 256.673,04 22,38% Tng s 385 34,90% 507.083,81 44,22%

3.4. Vng sng 3.4.1. Ni sng khu vc Khau Ca, Voc mi hch sinh sng sinh cnh rng thng xanh l rng trn ni vi t b tc ng, cao t 600 1300 m so vi mc nc bin (nh 2). Ni sng ca Voc mi hch l cc khu rng c nhiu cy g ln cao t 20 50 m v c nhiu cy vt tn vi chiu cao c th ln n 50 m, vi cc i din: Nghin Excentrodendron tonkinense (Tiliaceae), Trai Garcinia spp. (Clusiaceae), Sng Pometia pinnata (Sapindaceae), v.v.. Tng tn cao t 20 n 35 m gm cc cy g kh ln, tn rng v gn nh khp kn vi che ph ti trn 80%. i din cho tng ny l cc loi Th Diospyros spp. (Ebenaceae), Sng Pometia pinnata (Sapindaceae), Han voi Dendrocnide urentissima (Urticaceae), m balansa Bridelia balansae (Euphorbiaceae), v.v..

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Tng di tn gm cc cy c chiu cao xp x 10m vi cc loi cy g nh: Han xanh Laportea grandis (Urticaceae), Cc loi Nhc Polyalthia spp. (Annonaceae), Lng mang Pterospermum spp. (Sterculiaceae), c bit s c mt v u th ca hai loi Ho r Phlogacanthus sp. (Acanthaceae), v Nng Saurauia fasciculate (Actinidiaceae). Thc vt ngoi tng c s tham gia ca cc loi dy leo v cc loi thc vt b sinh vi thnh phn loi khng phong ph lm nhng c s lng c th kh nhiu, c trng cho mt kiu rng nguyn sinh nhit i. Thnh phn cc loi thc vt b sinh k sinh gm cc loi thuc Ngnh dng x nh T iu Asplenium nidus (Aspleniaceae) v cc loi i cn nam Macrosolen cochinchinensis, Mc v Trung Hoa Taxillus chinensis (Loranhthaceae) v cc loi thuc h Lan Orchidaceae, v.v. Cc loi dy leo kh n diu v thnh phn loi nhng kh phong ph v s lng gm: T qu Senguin Iodes seguini (Icacinaceae), Dy b khai Erythropalum scandens (Olacaceae), cc loi thuc cc h Thin l Asclepiadaceae, h Bu b Cucurbitaceae, h Nho Vitaceae, H Tit d Menispermaceae, v.v..

nh 2. Khu rng c Voc mi hch kim n khu vc Khau Ca, tnh H Giang

49

Trn 4 tuyn iu tra thc vt c 1.103 cy g c DBH 10 cm thuc 149 loi, 48 h (Ph lc 6 v Ph lc 7). Qua , cho thy mt cy g l 690 cy/ha. Cc cy g trn cc tuyn iu tra thc vt c DBH thay i t 10 cm n 180 cm, trong , s cy c DBH 20 cm l 736 cy (chim 66,73% tng s cy trn 04 tuyn). S cy c DBH 80 cm l 47 cy (chim 4,26%), chng ch yu l Excentrodendron tonkinense (Tiliaceae) v Sng Pometia pinnata (Sapindaceae); thm ch c mt s cy c DBH 150 cm (10 cy, chim 0,91%) (Biu 5). Tng tit din ca cc cy c DBH 10 cm l 114,67 m2, tng tit din trung bnh ca cy g trn mi ha l 71,67 m2/ha. Kt qu nghin cu ny cho thy rng khu vc Khau Ca (H Giang) ang trng thi tt, tnh n nh cao v m bo l mi trng sng tt cho Voc mi hch v cc loi ng vt khc ang tr ng .S cy400367 S cy

350311

300

250

200167

150

100

91 63

50

36 21 9 10 9 4 3 2 0 5 2 1 2

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

ng knh ngang ngc (DBH)

150

160

170

180

Biu 5. S lng cc cy theo cc tuyn iu tra thc vt khu vc Khau Ca, tnh H Giang (n = 1.103)

3.4.2. Kch thc vng sng khu vc Khau Ca (H Giang), Voc mi hch hin sinh sng trong mt khu rng nh khong 10 km2 v b cch ly hon ton vi cc khu rng lin k do c cc khonh trng cy rng cc nng ry ca con ngi bao quanh. Tuy nhin,

50

Bn 4. Cc im ghi nhn Voc mi hch khu vc Khau Ca, tnh H Giang 51

cc kt qu quan st cho thy Voc mi hch thng kim n khu vc trung tm (din tch khong 7 km2) t khi ra khu vc gip gn ng rang gii ca khu vc Khau Ca (Bn 4). L Hin Ho (1973) cho rng khu vc sng ca Voc mi hch c ng knh khong 1,5 2 km v din tch tng ng 1,7 3,14 km2 v hu nh khng thay i theo ma [4]. Phm Nht (1993) xc nh vng sng ca Voc mi hch c kch thc trung bnh l 4,55 km2 (r = 3,8 5,6 km2) v vng sng ca chng khng ph thuc vo s c th trong n m ch ph thuc vo ngun thc n [7]. Boonratana v L Xun Cnh (1994,1998) c tnh vng sng ca Voc mi hch phn khu Tt K, KBTTN Na Hang (Tuyn Quang) c kch thc khong 10 km2 [19,20]. Nhng nhn xt nu trn cho thy, hin rt kh a ra kt lun chnh xc v kch thc vng sng ca mt n Voc mi hch do sinh snh sng ca chng b tc ng v suy gim nghim trng. Cc khu vc ang nui dng nhng qun th cui cng l nhng khu vc b c lp, chia ct v c kch thc nh nh phn khu Tt K (KBTTN Na Hang) khong 200 km2, KBTTN Chm Chu khong 240 km2 v khu vc Khau Ca (tnh H Giang) khong 10 km2. iu ny cng t ra cho cng tc bo tn loi l khng ch ch trng n bo v nguyn vn cc qun th Voc mi hch hin c m cn cn phi bo v, duy tr v pht trin sinh cnh ca loi ny.

3.4.3. S dng vng sngNh ni phn trn, Voc mi hch thng kim n khu vc trung tm (din tch khong 7 km2) ca khu vc Khau Ca. y l khu vc rng tt nht v chu s tc ng ca con ngi t hn so vi cc khu vc cn li. Trong khu vc ny, Voc mi hch thng kim n cc khu vc thung lng v sn ni c cao t 600 1.300 m so vi mc nc bin, c bit l nhng khu vc c nhiu loi thc vc l thc n ca chng nh Nghin Excentrodendron tonkinense (Tiliaceae), Trai Garcinia spp. (Clusiaceae), Sng Pometia pinnata (Sapindaceae), Thch Bc b Acer tonkinensis, v T qu Senguin Iodes seguini

52

(Icacinaceae). Thm vo , y cng l khu vc c nhiu cy g to, tn dy v khp kn, c nhiu dy leo cao v rm rp, thun li cho vic di chuyn ca voc. Kt qu nghin cu theo cc tuyn iu tra thc vt cho thy cc loi thc vt l thc n ca Voc mi hch phn b kh ng u khu vc Khau Ca (H Giang). Tuy nhin, khu vc trung tm (ni c tuyn A v D) ca khu vc Khau Ca, ngun thc n ca Voc mi hch dng nh a dng v phong ph hn (Ph lc 6 v Ph lc 7). Cha c ghi nhn v s chuyn khu vc kim n ca tng n voc khu vc Khau Ca, tnh H Giang.

3.4.4. Ni ng khu vc Khau Ca (H Giang), Voc mi hch ng nhng khu vc nm cc khe ni ni c nhiu cy to v cao. Vo chiu ti ngy 06 thng 03 nm 2005, chng ti quan st v ghi nhn c ni ng ca 1 n Voc mi hch khu vc gn im A500 (ta : UTM 48Q 512313; 2526777). Ti im nay, Voc mi hch ng trn cc cnh thp ca cc cy Nghin to v cao hn 20 m. Cc nhm trong n chia nhau ng ti cc cnh v cy khc nhau. Ngoi ra, chng ti cng ghi nhn c nhng du vt ca chng (du phn) cho thy Voc mi hch khng ng mt ni c nh khu vc Khau Ca. Theo L Hin Ho (1973), Voc mi hch thng ngh ngi v tr n trn cc cnh cy cao c tn l kn rm [4]. i khi, cng c th gp Voc mi hch ng m trn cc nh cc khm na vu. Phm Nht (1993) cng c ghi nhn v ni ng ca Voc mi hch khu vc rng tre na. Boonratana v L Xun Cnh (1994,1998) ghi nhn Voc mi hch ng trn cc cnh thp ca cc cy v thng ng cc v tr sn dc trnh gi mnh v gi ma ng lnh [19,20]. Tuy vy, cho n nay, cha c cc nghin cu chi tit v ni ng v tp tnh ng ca Voc mi hch. Rt cn c nhng nghin cu di hn v chi tit hiu thm v tp tnh ng v ngh ngi ca Voc mi hch.

53

3.5. Cc kiu t th v vn ng 3.5.1. Cc kiu t thKt qu nghin cu cho thy, Voc mi hch khu vc Khau Ca c 3 kiu t th chnh sau: 3.5.1.1. Ngi (Sit) y l kiu t th m cnh cy nng phn ln trng lng c th, thn t th tng i thng, mng t ngi ln cnh cy. Voc mi hch c ba kiu ngi l: - Ngi co gi (Sit in): trng lng c th ca Voc mi hch c nng bi cnh cy, hai chi sau p st vi hng v u gi co gp, mng t ngi trn cnh cy v gn vi gt ca hai chi sau (nh 3). Kiu t th ny thng thy khi Voc mi hch ngi n, ngh ngi hay quan st trn cc cnh hoc thn cy to, vng chc. - Ngi dng chn (Sit out): hai chi sau ca Voc mi hch dng ra, trng lng c th c nng ch yu bi cnh cy. Hai chi sau nm gi cnh cy gi thng bng, mng t ngi trn cnh cy v cch xa vi gt ca hai chi sau (nh 4). Kiu t th ny cng thng thy khi cc c th Voc mi hch ngi ngh ngi hay quan st tm kim thc n trn cc cnh hoc thn cy to, vng chc.nh 4. Kiu ngi dng chn ca Voc mi hch nh 3. Kiu ngi co gi ca Voc mi hch

54

- Ngi vi chi trc u bm (Sit/forelimb suspend): Kiu ngi ny mt hay c hai chi trc ca Voc mi hch u bm vo cnh cy pha trc, mng t ngi trn cnh cy, trng lng c th ca Voc mi hch c nng bi cnh cy ny, bn chn sau t/bm ln trn cnh cy pha trc di; mt hoc c hai chi trc tm ly cnh cy pha trn gi thng bng v du bm nng mt phn trng lng c th (nh 5). Kiu ngi ny thng thy khi Voc mi hch tm kim v ly thc n hay quan st xung quanh trn nhng cnh hay thn cy nh, khng vng chc. 3.5.1.2. m bm (Cli