Hệ sinh thái rạn san hô Trường Sa (PDF)

B CNG THNG TRNG I HC CNG NGHIP TP.HCM VIN CNG NGH SINH HC & THC PHM

MN: TIU LUN:

SINH THI HC

H sinh thi rn san h vng bin qun o Trng Sa - Vit Nam

B CNG THNG TRNG I HC CNG NGHIP TP.HCM VIN CNG NGH SINH HC & THC PHM

MN: TIU LUN:

SINH THI HC

H sinh thi rn san h vng bin qun o Trng Sa - Vit Nam

GVHD: Nhm 2:

PGS.TS Trnh Xun Ng Lp HSH07LT 11306331 11261831 11307391 11276771 11270841 11315091 11299711

1. L Khnh Duy 2. Tng Th Thanh Thy 3. Nguyn Thanh Thy 4. Trn Th Minh Thy 5. Nhan Minh Tr 6. Phm Dng T Trinh 7. Phan Nguyn Thanh Tuyn TP.HCM, thng 11 nm 2011.

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MC LC I. M U ................................................................................................................. 1 II. NI DUNG ............................................................................................................. 3 1. San h v rn san h ............................................................................................ 3 1.1 San h ........................................................................................................... 3 1.2 Rn san h ..................................................................................................... 5 2. H sinh thi rn san h qun o Trng Sa .......................................................13 2.1 iu kin sinh thi hnh thnh v pht trin ..................................................13 2.2 c im t nhin ........................................................................................16 2.3 Qun x sinh vt sng trn rn san h qun o Trng Sa ..........................16 2.4 Vai tr ngha ..............................................................................................18 3. Tnh hnh khai thc .............................................................................................23 3.1 Hin trng s dng v khai thc ....................................................................23 3.2 Cc mi e da .............................................................................................27 III. KT LUN V KIN NGH ...............................................................................29 1. Kt lun ..............................................................................................................29 1.1 Ngun li sinh vt v vai tr trong sinh thi .................................................29 1.2 Hin trng khai thc thc t ..............................................................................29 3. Kin ngh cc phng php khai thc, s dng hp l ........................................30

Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa

GVHD: PGS.TS Trnh Xun Ng Nhm 2 - HSH07LT

I. M UVit Nam nm bn b Ty ca Bin ng, mt bin ln, quan trng ca khu vc v th gii. Vi 3.260 km ng b bin tri di trn 13 v , chy qua 29 tnh, thnh ph gm 124 huyn, th x vi 612 x, phng (trong c 12 huyn o, 53 x o) Vit Nam thu ht 20 triu ngi sng ven b v 17 vn ngi sng cc o.

Hnh: Ngun thy hi sn Bin nc ta c khong 11.000 loi sinh vt c tr trong hn 20 kiu h sinh thi in hnh thuc 6 vng a dng sinh hc bin khc nhau. Tr lng hi sn bin Vit Nam dao ng trong khong 3,1 - 4,2 triu tn/nm, vi kh nng khai thc 1,4 - 1,6 triu tn/nm. Trong , tr lng c ni v y vng bin qun o Trng Sa tuy cha c s liu c th nhng c d on l ni tp trung lng ln thy hi sn, cn phi c hng khai thc v pht trin lu di. Hu ht cc loi thy sn thng uuc tp trung cc rn san h v thm c bin, y cng l nhng h sinh thi nhy cm, c xem l h sinh thi ch th. Thy hi sn y nu b khai thc qu mc c th

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa sinh hot ca con ngi.


dn n suy kit, ng thi tc ng n mi trng bin dn n nh hng i sng

hiu r hn v h sinh thi rn san h vng bin qun o Trng Sa ni ring v v h sinh thi rn san h trn th gii ni chng. Nhm chng em xin thc hin bi bo co "H sinh thi rn san h vng bin qun o Trng Sa - Vit Nam". i dng l mt th gii mnh mng v cn nhiu iu b n, ngay c mt h sinh thi rn san h nh tn ti trong i dng vn cn nhiu iu m con ngi cn phi tm hiu. Vic thiu st l iu kh c th trnh khi, mong thy v cc bn ng gp gip bi bo co hon thin hn.

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II. NI DUNG1. San h v rn san h 1.1 San h San h l cc sinh vt bin thuc lp San h (Anthozoa) tn ti di dng cc th polip nh ging hi qu, thng sng thnh cc qun th gm nhiu c th ging ht nhau. Cc c th ny tit ra cacbonat canxi to b xng cng, xy nn cc rn san h ti cc vng bin nhit i. Tuy mt u san h trng nh mt c th sng, nhng n thc ra l u ca nhiu c th ging nhau hon ton v di truyn, l cc polip. Cc polip l cc sinh vt a bo vi ngun thc n l nhiu loi sinh vt nh hn, t sinh vt ph du ti cc loi c nh.

Hnh : Gii phu mt polip san h.

Polip thng c ng knh mt vi milimet, cu to bi mt lp biu m bn ngoi v mt lp m bn trong ging nh sa c gi l ngoi cht. Polip c hnh

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dng i xng trc vi cc xc tu mc quanh mt ci ming gia - ca duy nht ti xoang v (hay d dy), c thc n v b thi u i qua ci ming ny. D di ng kn ti y polip, ni biu m to mt b xng ngoi c gi l a nn. B xng ny c hnh thnh bi mt vnh hnh khuyn cha canxi ngy cng dy thm. Cc cu trc ny pht trin theo chiu thng ng v thnh mt dng ng t y polip, cho php n co vo trong b xng ngoi khi cn tr n. Polip mc bng cch pht trin khoang hnh cc (calices) theo chiu dc, i khi chia thnh vch ngn to mt a nn mi cao hn. Qua nhiu th h, kiu pht trin ny to nn cc cu trc san h ln cha canxi, v lu di to thnh cc rn san h. S hnh thnh b xng ngoi cha canxi l kt qu ca vic polip kt lng aragonit khong t cc ion canxi thu c t trong nc bin. Tuy khc nhau ty theo loi v iu kin mi trng, tc kt lng c th t mc 10 g/m polip/ngy (0,3 aox/ yard vung/day). iu ny ph thuc mc nh sng (sn lng ban m thp hn 90% so vi gia tra). Cc xc tu ca polip by mi bng cch s dng cc t bo chm c gi l nematocyst. y l cc t bo chuyn bt v lm t lit cc con mi nh sinh vt ph du, khi c tip xc, n phn ng rt nhanh bng cch tim cht c vo con mi. Cc cht c ny thng yu, nhng san h la, n mnh gy tn thng cho con ngi. Cc loi sa v hi qu cng c nematocyst. Cht c m nematocyst tim vo con mi c tc dng lm t lit hoc git cht con mi, sau cc xc tu ko con mi vo trong d dy ca polip bng mt di biu m co dn c c gi l hu. Cc polip kt ni vi nhau qua mt h thng phc tp gm cc knh h hp tiu ha cho php chng chia s ng k cc cht dinh dng v cc sinh vt cng sinh. i vi cc loi san h mm, cc knh ny c ng knh khong 50-500 m v cho php vn chuyn c cc cht ca qu trnh trao i cht v cc thnh phn t bo.

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Ngoi vic dng sinh vt ph du lm thc n, nhiu loi san h, cng nh cc nhm Thch ti (Cnidaria) khc nh hi qu (v d chi Aiptasia), hnh thnh mt quan h cng sinh vi nhm to vng n bo thuc chi Symbiodinium. Thng thng, mt polip s sng cng mt loi to c th. Thng qua quang hp, to cung cp nng lng cho san h v gip san h trong qu trnh canxi ha. To hng li t mt mi trng an ton, v s dng ixt cacbon v cc cht cha nit m polip thi ra. Do , hu ht san h ph thuc vo nh sng mt tri v pht trin cc vng nc trong v nng, thng su khng ti 60 m (200 ft). San h c th ng gp ln cho cu trc vt l ca cc rn san h pht trin nhng vng bin nhit i hoc cn nhit i. 1.2 Rn san h

Hnh : Mt rn san h in hnh.

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Rn san h hay m tiu san h l cu trc aragonit c to bi cc c th sng. Cc rn san h thng c thy cc vng bin nhit i nng m trong nc c t hoc khng c dinh dng. Mc dinh dng cao chng hn nh nc thi t cc vng nng nghip c th lm hi rn san h do s pht trin nhanh ca to. Ti hu ht cc rn san h, sinh vt thng tr l cc loi san h , cc qun th thch ti to ra b xng ngoi bng cacbonat canxi ( vi). S tch ly cc cht to xng, b ph v v dn ng bi sng bin v s xm thc sinh hc, to nn cu trc vi ln nng san h ang sng v lm ch tr n cho rt nhiu loi ng thc vt khc. Tuy san h c tm thy c cc vng bin nhit i cng nh n i, nhng cc rn san h ch hnh thnh khu vc hai bn ng xch o tri t v 30 Bc n 30 Nam; mc d cc loi san h to rn khng sng ti cc su qu 30 m (100 ft) nhit c nh hng t hn n phn b ca san h, nhng ngi ta thng cho rng khng c san h sng trong nhng vng nc c nhit di 18oC. Rn san h c xy dng t cc th h ran h to rn v cc sinh vt khc vi cu to c th cha cacbonat canxi. V d, khi mt u san h sinh trng, n to mt cu trc xng bao quanh mi polip mi. Song, cc loi sinh vt (nh c vt, nhm bin, hi min), v cc lc khc lm v cc b xng san h thnh cc mnh nh lp cc ch trng trong cu trc rn. Nhiu sinh vt khc trong cng ng rn san h cng ng gp b xng cacbonat canxi ca mnh mt cch tng t. Cc loi to san h (Coralline algae), gm to zooxanthelat (Symbiodinium spp.) v to si, l nhng nhn t ng gp quan trng i vi cu trc rn nhng phn rn phi chu sng ln (v d mt rn i din vi i dng). Cc loi to ny xy rn bng cc tit vi thnh tng lp ph ln b mt ca rn, nh lm tng tnh ng nht v cu trc ca rn. 1.2.1 S hnh thnh rn san h 1.2.1.2 S hnh thnh v pht trin rn san h

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Nh ni, rn san h l cc thnh phn to cacbonat canxi c ngun gc sinh vt, trong san h to rn ng vai tr quan trng trong vic hnh thnh v pht trin ca rn san h, sau n rong vi v cc sinh vt khc. Rn san h gm hai phn chnh: phn khung cng v khng gian lp y. Phn khung cng l khung xng ca cc qun th san h to rn c gn kt li nh rong v, cn khung gian lp y l cc l hng, cc khong khng trng rng trong khung cng ca rn ngay t khi rn mi hnh thnh v pht trin. Vt liu lp y cc khong trng l cc sn phm vn nt, mt phn l ca chnh qun th san h b phn hy phn cn li l do cc sinh vt khc. Sinh vt to rn l nhng sinh vt tham gia vo qu trnh to rn, ng gp vt liu do chng to ra vo vic xy dng v pht trin ca rn cc mc khc nhau. Cc kt qu nghin cu v thnh phn vt cht v cu to ca rn san h cho thy c nhiu nhm sinh vt khc nhau (k c ng vt v thc vt) cng tham gia vo qu trnh to rn, nhng phn ln cc vt liu xy dng cc rn san h l di tch ca nhm san h to rn. Vn u th ca san h lm cho chng tr thnh cc sinh vt to rn chnh l ch san h to rn l nhng sinh vt nh my sn xut vt liu cacbonat nhanh nht, nhiu nht v r nht. S d c c tnh u vit ny l v trong c th (cc t bo) ca chng c loi to cng sinh c bit l Zooxanthellae. Nh qu trnh quang hp ca loi to cng sinh ny m nng xut sinh hc s cp ca san h to rn cao hn nhiu so vi cc nhm sinh vt khc. Qu trnh hnh thnh v pht trin ca rn san h lun lun b chi phi, khng ch bi mt hoc mt s yu t. Cc yu t ny quy nh cch thc hay kiu hnh thnh v pht trin ca chng. C 2 quan in chnh v hnh thnh v pht trin ca rn san h:

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa o C ch sp ln kin to


o C ch nng kin to hay n nh kin to L thuyt th nht do ac-uyn xng l cc rn san h c hnh thnh v pht trin trn phng hot ng ln chm kin to ca v Tri t. Khi tc ln chm va v tri t bng vi tc pht trin ca san h to rn th cc rn san h lin tc pht trin v to nn cc tng trm tch cacbonat ngun gc sinh vt c b dy rt ln, ti hng ngn mt. Tt nhin, khi kin to nng mnh xy ra lm y bin nh cao khi mt nc th san h to rn s cht v rn s tnh trng thoi ha v b ph hy bi cc qu trnh ngoi sinh (phong ha, xm thc) v to nn cc b mt gin on trm tch nu sau qu trnh hot ng ln chm li xy ra to thnh cc trm tch tip tc. i km vi c ch ln chm kin to l c ch pht trin ca san h to rn theo kiu xy cao (khi tc ln chm y bin cn bng vi tc pht trin ca san h), xy vo (tc ln chm y bin nhanh hn mt cht so vi tc pht trin ca san h. Nu tc ln chm y bin ln hn nhiu so vi tc pht trin ca san h th san h khng kp pht trin v rn s ngng pht trin v c th b suy thoi) v xy cao (khi tc ln chm y bin nh hn tc pht trin ca san h hoc mc bin ng yn). Ngc vi quan im th nht, quan im th hai cho rng c ch hnh thnh rn san h l c ch nng kin to hoc n nh kin to. Tuy nhin, quan im ny hin cn ang c bn lun. 1.2.1.2 iu kin hnh thnh v pht trin cc rn san h S phn b trn th gii ca rn san h: san h to rn ch pht trin tt vng bin nng m p ca cc vng bin nhit i v cn nhit i ni c nhit khng

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thp hn 180C, nc c trong cao, mui khng di 28 0 00 , y cng khng c bn. Trn th gii din tch san h c tnh trn 284.300km2. S tn ti v pht trin ca san h to rn l iu kin quan trng cc rn san h hnh thnh v pht trin. Ngoi s gp mt ca cc c dn to rn cn phi c cc iu kin t nhin thch hp th mi c cc rn san h. Cc iu kin t nhin y l: cao ct nc trung bnh t 0-50m, c th ti 90m nu trong ca nc bin cao, ti u l 5-20m; Nhit mi trng nc bin t 160C 360C, ti u 250C 320C; Nng mui trong nc bin t 28 0 00 40 0 00 , ti u 32 0 00 36 0 00 ; trong nc bin cao; Ch thy ng lc mi trng trung bnh. Ngoi ra cn cc yu t: yu t cu to a cht nn y quyt nh s phn b khng gian, hnh thi v cu to ca cc rn san h; yu t hng gi v cc dng chy; dng triu; s dao ng mc bin; yu t sinh vt cng u l nguyn nhn to nn s pht trin mang tnh chu k hay giai on ca san h to rn v rn san h. V mt s yu t khc nh phi c nn y cng u trng san h bm ln v pht trin, c cc cht kh ha tan trong nc, khng c hoc t cc sinh vt gy hi cho san hCc iu kin mi trng qun o Trng Sa rt thch hp cho s pht trin ca san h to rn v s hnh thnh cc rn san h. 1.2.1.3 Hnh thi cc rn san h v ch gi ma Trong vng bin n - Thi Bnh Dng (trong c bin ng) yu t kh hu gi ma c nh hng trc tip ti vic hnh thnh cc rn san h.

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San h to rn vn l ng vt nhy cm vi s thay i ca kh hu, chng c s mn cm v phn ng i vi cc vt liu trm tch ang vn ng xung quanh. T cho thy rng cng ln v s nhp nhng ca sng do gi ma chc chn c nh hng trc tip v quyt nh i vi s phn b ca san h sng v c nhng vt liu san h cht, ti s m rng ca cc rn san h. iu kin pht trin trong mt vng bin c ch gi ma xen k nh qun o Trng Sa, cc rn san h kiu atoll thng c hai dng vng san h dng li lim, c v tr i nghch nhau, pht trin i xng, di tc dng ca hai lung gi thi xen k nhau trong nm, phn li ca vng san h hng v ngun gi thi ti theo chiu ng bc v ty nam. Diu ny khc vi hnh thi cu to mt vng san h pht trin mt i xng ca cc atoll di tc ng ca ngun lc sng v gi theo mt chiu khng i t vng khi, cc vng bin khng c ch gi ma, nh rn san h vng bin Autralia. 1.2.2 Phn b 1.2.2.1 Trn th gii

Hnh : Bn phn b cc rn san h trn th gii. Rn san h ngm c tnh bao ph trn 284.300 km. Vng bin n -Thi Bnh Dng (bao gm Hng Hi, n Dng, ng Nam v Thi Bnh Dng)

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chim 91,9% trong tng s. ng Nam chim 32,3% trong khi Thi Bnh Dng bao gm c Australia ch bao ph 40,8%. Ti i Ty Dng v bin Caribbe th rn san h ch bao ph 7,6% din tch san h trn th gii. Rn san h khng xut hin dc theo b bin pha Ty ca chu M cng nh chu Phi. V s gia tng ca mc nc v nhng dng bin lnh ven b lm gim nhit nc trong nhng vng ny. San h cng khng xut hin b bin Nam t Pakistan ti Bangladesh. Chng hu nh khng c dc theo b bin xung quanh ng Bc Bc M v Bangladesh v nc ngt t sng Amazon v Hng lm gim cht lng nc. Nhng rn san h v vng san h ni ting ca th gii: Rn san h Great Barrier - Qun th san h ln nht trn th gii, Queensland, Australia Rn san h Belize Barrier Qun th ln th hai trn th gii, tri ra t Quintana Roo, min Nam Mexico v dc theo b bin Belize ti qun o Bay ca Honduras. Di san h Hng Hi B bin ca Ai Cp v Rp Xt. Pulley Ridge - rn san h quang hp su nht, Florida. Nhiu rn san h c tm thy ri rc Maldives. 1.2.2.2 Ti Vit Nam Theo kt qu kho st s b,Vit Nam c khong 1.222 km2 rn san h, phn b rng ri t Bc ti Nam. Trong c h thng rn san h ti vng bin qun o Trng Sa cha c tm hiu nghin cu k. Cc nghin cu ca Vit Nam v san h ghi nhn gn 400 loi san h to rn ti vng Vnh Nha Trang, Ninh Thun, v Cn o, mi ni c hn 300 loi. Ti Vit Nam, c ti 90% cc loi san h cng ca vng

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n -Thi Bnh Dng v l khu vc c nhiu loi san h mm thuc ging Alcyonaria nht trong vng Ty n - Thi Bnh Dng 1.2.3 a dng sinh hc H sinh thi rn san h l mt h sinh thi a dng nht hnh tinh v c v nh rng ma nhit i di y bin, n ch phn b vng bin nng ven b. y l ni sinh sng, trng, n nu, kim mi cho rt nhiu loi hi sn. H sinh thi rn san h cn c nng sut sinh hc cao, l ngun sn sinh ra hu c, cung cp thc n khng ch cho chnh n, cho cc sinh vt sng trong rn m cn c ngha cho ton vng bin. V vy, y l ni lu tr ngun gen ca nhiu loi hi sn. Rn san h cng l mt h sinh thi rt nhy cm vi nhng bin i ca mi trng sng nn n cn c ngha ch th mi trng. S phn b mt rng ca san h ph thuc nhiu vo nhit , mui, a hnh v ch thu ng hc. cc vng ln cn cc o t, ni c nhiu tch bn, cht y l bn ct v si cui nn khng thch hp cho san h pht trin. Theo cc nh khoa hc, vi s loi san h c pht hin, c th khng nh nhm cc loi san h ca Vit Nam ni chung v h thng cc rn san h vng bin qun o Trng Sa vo mt trong nhng loi a dng nht th gii. Cc chuyn gia nc ngoi cng nh gi cao a dng v phong ph ca cc h sinh thi bin ca Vit Nam. Cc h sinh thi bin ny hin nui dng trn 11.000 loi sinh vt, trong c gn 2.500 loi c bin, 225 loi tm, hn 500 loi thc vt ni, gn 700 loi ng vt ni, gn 100 loi thc vt rng ngp mn, 5 loi ra bin, 15 loi rn bin, 25 loi th bin v 43 loi chim bin.

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa 2. H sinh thi rn san h qun o Trng Sa


2.1 iu kin sinh thi hnh thnh v pht trin Qun o Trng Sa l nhm cc o gm hn 100 o ln, nh v o ngm. vng bin Trng Sa cc rn san h c hnh thnh ch yu t cc loi san h to rn. Thnh phn loi san h to rn vng bin ny rt phong ph v a dng, cho ti nay pht hin c trn 329 loi thuc 69 ging v 15 h. Nhn chung, thnh phn khu h cc rn san h cc o khu vc qun o c s tng ng vi cc vng bin xung quanh nh Philippin, Indonesia, Australia. Cc rn san h vng bin Trng Sa thuc 2 kiu chnh: rn vin b v rn vng (kn v h), nhng c bn ging nhau v mt cu trc. Bng 1. c im cu trc rn san h Trng Sa- kiu rn vin b i cu to c im iu kin t San h to rn nhin i Cc sinh vt to rn khc

khe Rng 20-50m, su trn di San h ngho nn, Rong vi pht 1m, dng chy tng i ph 1-3%, ph bin cc trin, cc sinh mnh, b mt y khng ging: bng phng, mp m Porites, vt y

rnh ven b

motipora, ngoi ra cn c Favia, Favites

i

mt Su trn di 0m hi , Cc tp on san h nh, Rong vi u rng vi chc n vi trm phong ph tng dn th, chim 80mt, nn y cng, mp theo mnh, ngp nc v phi bin hng l cc ra bin 90% b mt dy 2ging 3cm; cc sinh m, ng lc mi trng khi, ph 5-50% ph y,

bng rn

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa kh theo chu k thy triu. Porites,

GVHD: PGS.TS Trnh Xun Ng Nhm 2 - HSH07LT Motipora, vt y

Favia, Favites i rn mo Hp, cao 0.5m so vi mt San h ngho nn, u Rong vi u bng rn, cu to t khung th dng cnh ngn, th xng san h cht, cng mp, sng thnh tp rn, ng lc mi trng on nh mnh i rn sn dc khc nhau, nn y San h phong ph, a Rt phong ph cng, ng lc mi trng dng, ph ti 70-80% v a dng cc gim dn theo chiu su y v cao hn, tp on ln nhm sinh vt bin i gim dn theo su. khc nhau Cha cu nghin

chn Trm tch ct sn ln vn Cha nghin cu xc sinh vt

sn rn

Bng 2. c im cu trc rn san h Trng Sa- kiu rn vng

i cu to c im iu kin t San h to rn nhin i

Cc sinh vt to rn khc

mt Nn y cng, mp m, San h pht trin phong Rong vi pht ngp nc triu ln v ch ph gm cc i din trin trn cc h khi triu xung. Acropora, Porites, b mt san h

bng rn

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GVHD: PGS.TS Trnh Xun Ng Nhm 2 - HSH07LT Pocillopora.. cht, cc sinh vt y pht trin ph phong

i rn

mo Hp, cao 0.3- 0.5m so vi San h ngho nn, u Cc sinh vt mt bng rn, cu to t th dng cnh ngn, y sng bm khung xng san h cht, mp, dng ngn, dng c nh trn cng rn ph nh cc ging nn cng (s, c, tm, cua..)

Motipora, Acropora i rn sn dc khc nhau, phn T trn thoi hn phn di 10-20m, san

h Rt phong ph

phong ph, a dng, v a dng cc ph c ch ti 100% nhm sinh vt gm cc dng cnh, khc nhau dng cy, dng l, dng phu nh Acropora, Favia, Pavona Di 20m, san h tr nn ngho nn v tha tht

i lng h su ti 40m, h khng San h dng cnh di v trm tch v mnh vn tch u t th:

Cc sinh vt

bng phng m rt mp m, mnh pht trin chim khc pht trin Acropora phong ph v Montipora a dng Hydrnophora

palmata, digitata, exesa

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa i

GVHD: PGS.TS Trnh Xun Ng Nhm 2 - HSH07LT Sinh vt ngho nn, n iu

chn Trm tch ct sn ln vn Cha nghin cu c b dy kh ln, xc sinh vt

sn rn

2.2 c im t nhin 2.3 Qun x sinh vt sng trn rn san h qun o Trng Sa 2.3.1 Rong bin Gm 186 loi, 33 h thuc 4 ngnh, c th nh sau: o o o o Ngnh rong Rhodophyta c 103 loi Ngnh rong nu Phaeophyta c 20 loi Ngnh rong lc Chlorophyta c 54 loi Ngnh rong lam Cyanophyta c 54 loi.

2.3.2 S a dng ca ng vt y C 5 nhm chnh c nghin cu l ngnh Rut khoang (tr san h cng), lp giun nhiu t, lp Gip xc, nhng Thn mm v ngnh Da gai. y l cc nhm ng vt c ln quan trng nht trong thnh phn qun x rn san h Trng Sa. y thng k c 554 loi ng vt y thuc 192 ging, 106 h. Trong s 5 nhm trn Thn mm c s loi ng nht vi 276 loi chim 49.5% tng s loi chung, ng th 2 l Gip xc (83 loi, 15.0%) sau n Giun nhiu t (112 loi, 20.2%), t nht l nhm Rut khoang (26 loi, 14.7%).

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2.3.3 S a dng ca c bin qun o Trng Sa C l nhm ng vt rt a dng, phn b rng, c kh nng bi li rt gii do c t s khc nhau v thnh phn loi trong cng mt khu vc khng rng v cng loi sinh cnh nh san h. Theo kt qu thu nhn c, khu h c san h vng qun o Trng Sa c khong 524 loi, thuc 138 ging, 48 h. Qua thng k cho thy cc h c san h in hnh c s loi ln nht: h c thia (Pomacentridae)- 81 loi, h c bng chy (Labridae)-63 loi, h c bm (Chaetodontidae)- 35 loi, h c m (Scaridae)- 33 loi. Tip n l cc h c ui gai (Acanthuridae)-26 loi, h c hng (Lutianidae)- 25 loi Thnh phn c sng trong xun x san h: Thnh phn c vng lai: bao gm cc loi c phn b rng trong bin ng v Thi Bnh Dng. Chng c th n rn san h trong mua trng, kim n hay ln trnh k th trong thi gian nht nh. i din cho thnh phn ny c cc loi c ni thuc h c mp (Carcharhinidae), c chun (Excoetidae), c thu ng (Scombridae) v cc loi c y thuc h c ui (Daryatidae), c kh (Carangidae), c phn (Mullidae) Thnh phn c san h: bao gm thnh phn c bn nht, c s loi chim ti hn 94% tng s loi ca khu h v c mt c th ng nht. Gm cc h: h c thia (Pomacentridae), h c bng chy (Labridae), h c bm (Chaetodontidae), h c m (Scaridae), cc h c ui gai (Acanthuridae), h c sn (Holocentridae)Nhn chung, cc loi c thuc thnh phn ny sng n nh trong h sinh thi, khng di c xa khi vng phn b ca san h. S a dng sinh cnh c xc nh bi s a dng v ni (habitat), cc qun x v cc qu trnh sinh thi din ra trong h sinh thi san h. Qun o Trng Sa, do

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a hnh phc tp to nn nhiu ni c tr cho cc tp hp loi khc nhau sinh sng. Trong qun o Trng Sa, ngoi thnh phn c vng lai sinh sng, tp on c sng n nh trong h sinh thi san h c nhng phng thc sng thch hp vi ni c tr: Sng ln trong cc qun th san h. y l phng thc sng ch yu ca cc loi c san h. c im chung ca cc loi c sng theo phng thc ny l thng c thn hnh cao, mu sc sc s, bi li chm chp v t khi ra khi qun th san h. Sng trong hang hc: s ny khng nhiu v t khi ra khi ni c tr. Hu ht c nhm ny thuc loi d. i din nh cc loi c lch hay c m. C sng trong cc thm rong, c bin: sng ln l, chp chn, khi c nguy him ln ngay vo cc bi rong, c kh pht hin. C sng cng sinh: tuy l ng vt c xng sng bi li trong nc nhng li c phng thc sng cng sinh rt c bit vi cc ng vt y khc. V d nh cc loi c thia khoang c sng cng sinh vi hi qu. 2.4 Vai tr ngha Cc rn san h a dng v tuyt m tham gia hnh thnh v bo v hng ngn hn o. Chng cng c tm quan trng ln nhiu o ln v vng b bin trong vic bo tn t ai v s tn ti ca con ngi. Rn c ngha tht s i vi cng ng ven bin v cc quc gia nhit i. Do s khc nhau v yu t kinh t, x hi, vn ha, gi tr ca rn san h c nh gi mt cch khc nhau gia cc nc hoc cc cng ng. i vi cc cng ng kinh t pht trin, rn san h c coi l ti nguyn v x hi v vn ha. Gi tr kinh t c hiu phng din gii tr v du lch. Cc c sn cng rt hp dn nhng khng phi l thit yu. Nhiu cng ng nh th h tr cho chng trnh nghin cu khoa hc nhm hiu bit chc nng ca cc h rn san h v t hp phc tp ny lin quan nh th no n mi trng bin v lc a. Sau y l nhng c tnh ca rn san h gp phn to nn gi tr v mt x hi v vn ha v c coi l mt ngun li c bit.

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa 2.4.1 i vi cc loi sinh vt rn san h


Rn l mi trng m nhiu loi ph thuc hon ton vo n. Nn y cng trn rn l ni m nhiu sinh vt y c trng nh s, trai, hi min, hu bin, hi qu v to bm sinh trng. Vi nhng loi ny rn san h l ni bt buc. Nhiu loi khc coi rn l ni cp thit trong giai on d b e da ca chu trnh sng v rn c s dng kim n, trng hoc c coi l bi ng con v tr n. Vic thot khi e da nh ni l c s quan trng duy tr ngh c v gip trnh khi s tiu dit ca cc loi c gi tr cao. Ra bin l mt v d v chc nng ny ca rn san h. Chng l thnh phn quan trng ca qun x rn san h. Ra Xanh i v p trng trn bi ng con trn cn. i Mi khng di c xa nh Ra Xanh v phn b rn nhiu hn. Chng n ng trn rn v trng trn cc bi ct san h ca cc o san h hoc cc o c rn rim. 2.4.2 i vi h sinh thi Con ng trao i cacbon c bit l tnh cht ring ca h sinh thi rn san h phn bit vi cc h sinh thi khc. Quang hp ca cc thc vt t to roi n bo, rong thng n rong vi c nh cacbon vo cc hp cht v to ra cc cu trc sinh hc hoc i vo chui dinh dng. Sn phm quang hp trn n v din tch ph thuc vo tng nng lng mt tri v s tiu gim cng cng nh s thay i ph nh sng khi i qua ct nc. Qu trnh ny thuc vo v tr a l v trong ca nc. S c nh cacbon cn ph thuc vo cht lng nc cng nh hm lng dinh dng, pH, CO2 , O2, H2CO3 ha tan, nhit v mui. Con ng to nn cu trc sinh hc l qu trnh tch ly cc khi vi chng gn kt vi nhau thnh b khung ca rn. Con ng to dinh dng cung cp cho chui thc n thc vt, ng vt n thc vt v n tht v phn hu bn b do vi sinh vt. Thnh phn tiu th v phn hy c b sung vi mc khc nhau bi vt cht hu c nhp khu gm mn b, thc vt ph du, ng vt ph du v ng vt c xng sng. Ph dinh dng ca rn san h v qun hp y rn thay i t u th l t dng n

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa c bn ph thuc vo vt cht hu c t ngoi vo.


Sinh vt sn xut ca rn san h cc k a dng. Chng bao gm tt c cc nhm rong to v c th c c bin. Thnh phn sn xut ring bit ca san h l to cng sinh Zooxanthellae vi nhiu loi to roi n bo sng trong t bo ca ng vt c qu trnh canxi ha. Sn phn s cp t sinh vt ph du (thc vt ph du) i khi tr nn quan trng trong cc lagoon ca rn vng, nhng thng nh hn so vi sn phm to ra t nn y cng v ct. Mt v sinh khi ca sinh vt sn xut khc nhau rt ln gia cc rn nh l hm s ca ch dinh dng ca mi trng xung quanh, hin trng din th nng lng sng v p lc ca ng vt n thc vt. San h cng l thc n cho nhiu loi c v ng vt khng xng sng v hnh thnh nhm n san h vi nhiu kiu dinh dng khc nhau. Chng li c kim sot bi nhm vt d th cp tiu th c th trng thnh hoc u trng nhm trc. Cui cng ca thp dinh dng ca rn san h l cc vt d nh c mp v cc loi c xng thuc vo nhiu lp dinh dng. ng vt n tht sng y v gia tng nc bao gm n 60% tng s loi. Sn phm th cp c th thu hoch n nh t rn (ch yu gm c, thn mm, da gai, gip xc) c tnh khong 15 tn/ha. Sinh vt hnh thnh cu trc sinh hc l sinh vt y sng bm c kh nng to b xng gm aragonic, calcite, khong trn c s CaCO3 vi nng vt ca Mg v Sr. Nhm ny gm hai thnh phn l sinh vt to khung thuc nhm san h v rong vi dng ph cn sinh vt khng to khung gm phng x trng, rong vi dng cy v thn mm. hnh thnh cu trc sinh hc, rn san h cn c nhm sinh vt h tr gm 3 nhm: nhm tng cng canxi ha l cc to roi n bo cng sinh bi hot ng ng ha ca chng h tr cho s canxi ha trong vt ch. Nhm xi mn sinh hc a dng v thnh phn gm c, hi min, thn mm hai mnh v, Sipunculida, cu gai, giun nhiu t v to si. chng cng c th c b xng vi hoc gm mn b mt. Nhm ch bin trm tch (sediment operators) c i din l thn mm,

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa tiu ha to silic trn y.


giun nhiu t, hi sm v c c kh nng chuyn trm tch y qua ng tiu ha

Rn san h cn c cc sinh vt xc tc (facilatous) nh hng ln cu trc qun x. V d, ng vt n thc vt gip cho san h sinh trng bnh thng thng qua vic ngn cn s pht trin qu mc ca chng. T nm 1955, Odum & Odum cho rng s tch ly sinh khi cao rn san h ph thuc vo 2 yu t: s dng c hiu qu nng lng mt tri v chu trnh khp kn cht dinh dng. Nng lng mt tri c c nh bi to cng sinh, vi to trn b mt y v cc loi rong. Chu trnh dinh dng din ra trong t bo san h gia to cng sinh v vt ch cng nh gia cc ng thc vt trong t hp phc tp ca rn v chui thc n nhiu tng. Tuy nhin, cc qu trnh nng lng khng ging nhau gia cc i trong mt rn, gia cc rn thuc cc vng a l khc nhau v cc mc pht trin khc nhau. Rn san h trong trng thi cn bng c t s gia sn xut v h hp (P/ R) xp x bng 1. Khi rong to u th P/ R > 1, nhng vng ct v si phi nhp khu mn b ch c h s P/ R < 1. 2.4.2 i vi i sng con ngi Cc rn san h a dng v tuyt m tham gia hnh thnh v bo v hng ngn hn o. Chng cng c tm quan trng ln nhiu o ln v vng b bin trong vic bo tn t ai v s tn ti ca con ngi. Du lch c nh gi l mt trong nhng ngnh cng nghip ln trn th gii v mang nhiu nt vn ha x hi. Vng ven bin v cc o vng nhit i thu ht hot ng du lch nh cc bi bin hp dn, cc rn san h y mu sc, ng thc vt a dng, kh hu m p v c dn thn thin, a dng v vn ha. Khch du lch ngy nay tm n cc ngun ti nguyn t nhin nh mt tri, ct v bin. i vi cc cng ng kinh t pht trin, rn san h c coi l ti nguyn v x hi v vn ha. Gi tr kinh t c hiu phng din gii tr v du lch. Nhiu cng

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ng nh th h tr cho chng trnh nghin cu khoa hc nhm hiu bit chc nng ca cc h rn san h v t hp phc tp ny lin quan nh th no n mi trng bin v lc a. Sau y l nhng c tnh ca rn san h gp phn to nn gi tr v mt x hi v vn ha v c coi l mt ngun li c bit. Sc sn xut Cc rn san h c coi l h sinh thi c nng xut cao nht trn th gii. Chng chim khong 0,1% din tch b mt qu t. Nhng ngh c lin quan trc tip hoc gn tip vi rn san h v c nh gi l chim khong 10% sn lng ngh c th gii. Sc sn xut cao c c nh tnh hiu qu ca chu trnh chuyn ha vt cht. Trong to cng sinh Zooxanthellea, to c kh nng c nh N v vi khun sng trong trm tch ng vai tr quyt nh. Tnh a dng Rn san h cng c coi l h sinh thi a dng nht. chng bao gm nhiu loi c trng i din cho hu ht cc nhm ng vt bin. Mt s lng ln cc hang hc trn rn cung cp ni tr n cho c, ng vt khng xng sng c bit l c con. b sung cho chin lc cnh tranh, cc loi sng trong iu kin mt dy trn rn c th hnh thnh nhiu kiu quan h. Mt trong nhng quan h ph bin nht l quan h i khng. Cc phc cht ha sinh hot tnh cao c chit xut t nhiu i tng san h, mt s c th c s dng trong y hc. Tnh a dng ca cc loi trn san h cao n mc nhiu loi; c bit l ng vt khng xng sng nh giun, tm vn cha c m t. V vy rn c coi l "kho d tr " gen. Chng nm gi nhiu du vt chng ta c th hiu c cc qun th ng thc vt pht trin nh th no v c chc nng g. Mt s loi mang li li ch kinh t v x hi trc tip cho con ngi. Gi tr v mt "kho gi tr " gen ca cc loi

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c gi tr c chng t qua 2 v d v s di chuyn thnh cng Oc n Trochus niloticus Thi Bnh Dng v c thc phm Hawaii. Ni ca cc loi Rn l mi trng m nhiu loi ph thuc hon ton vo n. Nn y cng trn rn l ni m nhiu sinh vt y c trng nh s, trai, hi min, hu bin, hi qu v to bm sinh trng. Vi nhng loi ny rn san h l ni bt buc. Nhiu loi khc coi rn l ni cp thit trong giai on d b e da ca chu trnh sng v rn c s dng kim n, trng hoc c coi l bi ng con v tr n. Vic thot khi e da nh ni l c s quan trng duy tr ngh c v gip trnh khi s tiu dit ca cc loi c gi tr cao. Ra bin l mt v d v chc nng ny ca rn san h. Chng l thnh phn quan trng ca qun x rn san h. Ra Xanh i v p trng trn bi ng con trn cn. i Mi khng di c xa nh Ra Xanh v phn b rn nhiu hn. Chng n ng trn rn v trng trn cc bi ct san h ca cc o san h hoc cc o c rn rim. Gi tr thm m S phc tp v qu trnh hnh thnh, s khc nhau v hnh dng mu sc v trng thi ca sinh vt lm cho rn c v p him c v s li cun i vi con ngi. Rn l ngun cm hng v i tng cho cc nh nhip nh di nc v ca cc nh t nhin hc. Rn cng l ngun li to ln phc v cho gii tr v du lch v c coi l mt gi tr vn ha hin i. 3. Tnh hnh khai thc 3.1 Hin trng s dng v khai thc Nm trong Bin ng, qun o Trng Sa c bao quanh bi nhng vng nh c tr ph v giu c v ti nguyn du m cng nh kh t. Vi nhng ngun

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa ngi.


li di do ny, qun o Trng Sa tr thnh im khai thc l tng ca con

Cc o ni ln nh o Trng Sa ln, Nam Yt, Song T Ty l cc o thng xuyn c nhiu ngi v khai thc. Hu ht trn cc o ni, ngi ta quy hoch s dng t xy dng nh , cc cng trnh qun s. Ngoi ra, cn c cc h thng giao thng, ho, cc sn vn ng, hay cc vn rau to ngun thc n xanh cho con ngi sng trn o. Hu nh hin nay cc vng t trn o c khai thc ht. Mt ngi sng trn cc o kh ng, tuy nhin ngun thc phm khng di do. Hu nh thc phm u c cung cp t t lin. Trong khi , sinh vt trn o v ven o b khai thc lin tc. Cc loi sinh vt c th lm hng m ngh nh trai, c, san h trc u c khai thc v mang vo t lin. Mt s loi ng vt qu him nh i mi, vch cng b khai thc qu v hin nay ang trong tnh trng ct kit, mt s loi c nguy c tuyt chng. Ngoi vic khai thc mt cch v , con ngi cn khai thc khng ng cch nh dng thuc n, mn gy ra hu qu nghim trng cho h sinh thi nh gim a dng sinh hc, ph hy h sinh thi, lm suy yu bc tng chn song t nhin. Tc xi mn, lt l ngy cng tng cao lin quan trc tip n hnh vi khai thc v khng hp l ca con ngi. Thi gian gn y, mt s ngi cn t chc khai thc xa b, sn bt c mp khng hp l. Hoc khai thc cc loi thy hi sn khc nh hi sm, bo ng. y l mt vic lm gy hi, v dn n s cn kit ti nguyn, lu dn mt s loi c th tuyt chng. Hu qu lm suy thoi h sinh thi san h nng n, mt cn bng trong t nhin, mt i cc ngun li m h sinh thi san h mang li. Tnh hnh khai thc hin nay ca qun o Trng Sa c th hin qua cc mt: Nng nghip

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Cng nh cc ni khc, hot ng nng nghip vng ven b cng chim dng mt din tch t ln v gy nh hng n cht lng mi trng vng ven bin. Vng ven b c cc iu kin kh hu v t ai thun li cho nng nghip. Ngoi chc nng ht sc r rng l cung cp lng thc cho cng ng ven b, nng nghip cng to ra nguyn vt liu cho cng nghip. Nng nghip cng to ra thc phm cho cng ng a phng, c dn ven b. Nng nghip vng ven b thng c nhng li ch t cc iu kin mi trng thun li, t cc vng t tt v s giao thng lin lc ng bin cng nh t s pht trin ca cng nghip v du lch ven b. Tuy nhin, hot ng nng nghip ven b cng b tc ng lin quan n v tr gn bin bao gm nguy c ca vic nhim mn t v nc; cht lng nc km v khng an ton xut pht t cc hot ng vng thng lu; s cnh tranh gay gt v t vng ven b. Ngc li, lnh vc nng nghip cng nh hng ln cc lnh vc khc. Cc mi tng tc ny c th tch cc nhng thng l tiu cc v xoay quanh cc vn cnh tranh v t, nc, ngun vn v lao ng. Tc ng tiu cc ca nng nghip i vi cc lnh vc khc bao gm: vic lm nhim ngun nc nh hng trc tip ln ngh c thng qua cc ha cht dng trong nng nghip v lm tng c gy hi cho cc rn san h v cc cng do vic xi mn t. Hu qu lm mt vng c tr sinh vt v suy gim a dng sinh hc vng ven b cng c th xy ra. Du lch Du lch l mt ngnh kinh doanh tng hp khng nhng cha ng trong nhng gi tr kinh t n thun m c nhng gi tr v lch s, vn ha ca mt vng min. Du lch nhng vng ven b ang l ngun thu nhp cao cho cc nc ven b bin. Ti y, ngi ta s c thng thc nhng phong cnh p nhng vng ca sng ven bin, nhng bi bin tuyt vi, cc o vi y hang ng, b ct mn, vng m ph, rng ngp mn, cc rn san h. Vng ven b l iu kin l tng

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pht trin tim nng du lch, ngh mt v iu dng, km theo l cc hot ng dch v phc v cho du lch gii tr nh l bi thuyn thng ngon, ln, lt sng, cu c tm bin, ngm san h. Tuy nhin, bn cnh nhng li ch em li, th du lch gii tr ang gy ra nhng tc ng nh hng n mi trng ven b. Cc hot ng ca con ngi trong lnh vc ny gp phn lm cho mi trng ven b b suy thoi. Cc tc ng tiu cc ca du lch n mi trng vng ven b c th k l: Khai thc qu mc v khng hp l hi sn phc v nhu cu thng thc c sn bin cho du khch. Hot ng tham quan, du lch cng lm nh hng n s lng, ni c tr v sinh sn ca mt s loi. Mi trng ven b cng ang chu s tc ng ca nhng ngun nhim t t lin do cht thi sinh hot ca du khch vng lai: cc cht thi ny c nguy c lm thay i cht lng nc, cc h sinh thi vng ven b. Khch du lch v phng tin vn chuyn khch du lch c th c th em n mt s loi sinh vt ngoi lai, nh hng n s pht trin ca mt s h sinh thi ven b. Tm li, tc ng ca du lch vng ven b c th gy ra nhng thm ho i vi mi trng v cng ng a phng. Gii php cho cc vn ny l pht trin du lch da vo cc nguyn l ca s bn vng. Trc khi thc hin pht trin du lch ven b, cn phi nh gi v phn loi cn thn cc khu vc ven b cng nh tnh nhy cm v sinh thi, x hi v vn ho ca n. Cn phi c cc k hoch v mc tiu qun l i vi tng vng. Nhng vng c nhy cm cao, c c th v mt mi trng cng nh c ngha v vn ha cn phi thng xuyn bo v, l cc vng khng nn pht trin.

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa Nui trng thy hi sn


Vic nui trng thy sn c ngha ln trong vic cung cp protein v gim thiu i ngho cho ngi dn sng vng ven b. Tuy nhin hot ng nui trng thy sn cng em li nhiu tc hi v mt mi trng y. Trc ht hot ng nui trng thy sn cnh tranh v khng gian vi cc lnh vc khc nh du lch, gii tr v nng nghip. c th pht trin, nui trng thu sn cn phi c nc sch, khng c cc sinh vt l du nhp; xy dng c s h tng, nh xy dng nh ca, kho hng, ng s. Khai thc khong sn v du m Khong sn l vt liu ca v tri t, c hnh thnh t qu trnh t nhin m con ngi c th khai thc, s dng mt cch trc tip hay gin tip cho cc nhu cu ca cuc sng. Qu trnh pht trin vn minh ca nhn loi gn lin vi qu trnh pht trin kh nng s dng nguyn liu khong sn. S phn chia cc thi i vn minh th hin rt r vn ny cc thi k c, mi, ng, st. c bit trong iu kin pht trin cao ca khoa hc k thut trong thi i ngy nay th kh nng khai thc khong sn ngy mt nng cao. Vic khai thc s dng s dng ti nguyn khong sn thc y s pht trin ca cc nn vn minh nhn loi, em li s thnh vng cho nhiu lnh th. Tuy nhin, vic khai thc ti nguyn cng gy ra nhiu vn mi trng nghim trng nh hng n s pht trin ca cc ngnh kinh t khc. Ty theo tng loi khong sn m con ngi c phng thc khai thc, ch bin v tng tr cho thch hp a li hiu sut cao nht. Cho d khai thc khong sn bng cng ngh no i na th hu qu m mi trng vng ven b phi gnh chu cng rt nghim trng. 3.2 Cc mi e da

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Do ngun li sinh vt kh di do, nn qun o Trng Sa thng xuyn b e da bi con ngi. S khai thc khng hp l, khai thc khng ng cch lm cho h sinh thi rn san h qun o Trng Sa ngy cng suy vong. Cc tc ng ca con ngi n mi trng vng ven b c th xp vo 3 loi. Cc tc ng vo cu trc, bt ngun t vic bin i v ph hy ni c tr. Cc tc ng vo qu trnh, l hu qu ca vic tc ng c ch ch v khng ch ch vo cc nhn t vt l ha hc v sinh hc ca mi trng. Cc tc ng tin ch, s thay i mi trng lm gim c hi hin ti v tng lai i vi vic s dng mt vng thin nhin bao gm c vic s dng m hin nay khng bit trc. Cc hot ng pht trin mang ngha phc v cho li ch ca x hi, gia tng tin ch cho con ngi. Tuy nhin, nhng hot ng ny cn phi s dng cc ngun ti nguyn thin nhin khc nhau nh t, nc, nguyn nhin vt liu, do vy c nguy c gy hi n mi trng v cc h sinh thi t nhin bng nhiu cch khc nhau. Ni chung, cc tc ng phi hp i vi vng ven bin trong cc th cng nh vng ven bin nng thn bao gm: Pht trin xy dng (nh cc bn du thuyn v cc chn sng) c th gy nn s ph hy ni c tr v gy xo trn cuc sng t nhin. Cc loi hnh cng nghip khc nhau s mang n nguy c nhim cho mi trng. Thay i vic s dng t (v d chuyn i nng thn thnh thnh th) gy ra s suy thoi vng ven b, tng kh nng tc ng ca thin tai nh l lt. Ci to t cho bn cng, kho hng v pht trin th lm mt din tch vng triu v ti nguyn nc. Hot ng sn xut nng nghip gp phn vo vic pht tn cc cht ha hc v cht dinh dng theo dng nc lm tng s lng ng trm tch do t b xi mn. Du lch v gii tr dn n vic thay i mi trng ven b v s dng qu mc ti nguyn.

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III. KT LUN V KIN NGH1. Kt lun 1.1 Ngun li sinh vt v vai tr trong sinh thi Qua cc t kho st, cc nh nghin cu thng k c rn san h vng bin qun o Trng Sa hin c hn 465 loi thc vt ph, 359 loi ng vt ph du, 326 loi san h, 186 loi rong bin, 439 loi ng vt khng xng sng, 524 loi c san h, 348 loi c vng khi v c kh nng vt khi con s ny nhiu ln. T s lng loi cho ta thy h sinh thi rng san h c a dng sinh hc cao v ang trong giai on pht trin. V kh nng linh ng p tr nhng din bin bt thng ca mi trng mt cch hu hiu h sinh thi ngy cng pht trin bn vng. T vic pht trin h sinh thi ca mnh, h sinh thi rn san h cn tc ng tng h qua li vi cc h sinh thi xung quanh n, gp phn gi cho sinh quyn l mi trng t nhin m con ngi c th sng v lm vic. H sinh thi ny cung cp cho chng ta thc phm, thuc men, ng thi cng mang cho chng ta nhng gi tr v mt thm m, tinh thn, vn ho, gii tr v khoa hc. Hiu bit ton cu ca chng ta v quan h tng h v s ph thuc ln nhau gia cc h sinh thi vn ang trong qu trnh pht trin. Tnh a dng ng kinh ngc ca s sng cha ng gi tr ni ti ct yu, bi v n to cho cc h sinh thi v sinh vt kh nng t phc hi cao hn. N lm cho mt h thng t nhin hp thu v hi phc sau khi chu tc ng bt li t pha con ngi, v lm tng tnh bn vng. 1.2 Hin trng khai thc thc t Tuy cha thng k c sn lng khai thc hi sn hng nm, nhng t a dng sinh hc ta cng thy c kh nng m h sinh thi san h cung cp cho con ngi khi lng ln sn phm lm nguyn liu trong thc phm, y hc, m ngh, Ngoi ra, y cng l ni c tim nng du lch bin cha c khai thc.

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa sinh vt trong vng:


Nhng con ngi vi kh nng ca mnh khai thc lm cn kit ngun li

Mt s ng vt qu him nh vch, i mi thng b sn bt ht khi ln o trng. tnh trng ny din ra trong thi gian di lm ngun li b cn kit, nhiu loi c nguy c b tuyt ging. nh c bng thuc n rt ph bin, hu qu lm suy gim a dng sinh hc rt nhanh chng nhng khu vc mn n, ph hy ni c tr vng c a dng cao nht, ph hy san h v rn san h lm suy yu bc tng chn sng. Tc xi l ngy cng gia tng. Mt s n v dn s cn t chc tng i tu ra khai thc trai tai tng v sn bt c mp ly vy. C mt s i tu cn trang b thit b ln, ngi ln c th lu di nc tm v khai thc hi sn. nc bin rt trong, tm nhn c th 20-30 m mi sinh vt c th b pht hin v sn bt bt k nh bo ng, tm hm, hi sm. y l 1 vic lm gy hi v d lm cn kit ngun ti nguyn v lm mt cn bng t nhin trong h sinh sinh thi, hu qu chng nhng lm suy gim ngun li m cn dn n lm suy thi rn san h. Trai tai tng v tm hm v cc sinh vt chm ln, sng lu nm, li vng nng d khai thc. Hu qu dn n nhiu loi c sn ngy cng tr nn khan him. 3. Kin ngh cc phng php khai thc, s dng hp l Ngun li thy hi sn ti rn san h qun o Trng Sa phong ph, nhng khai thc tt v lu di ngun ti nguyn ny, chng ta cn phi c mt s bin php khai thc hp l nh: c bin php kim sot qun l cht ch, c bin php b p a dng sinh hc, nng cao nhn thc ngi dn, Ty tng i tng khai thc m ta c phng php nghin cu, khai thc ph hp: Ngun li C

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Ch yu l thnh phn c san h phong ph v ngun c ni i dng nhng cha c iu tra nghin cu k. khai thc tt ngun ti nguyn ny, mt s phng thc c s dng nh sau: T chc iu tra thm d ngun li c ni rn san h vng bin qun o Trng sa, xc nh tr lng v khu vc phn b tp trung ca c, xc nh ma v khai thc v nghin cu c im sinh hc ca cc loi c gi tr kinh t cao. Do v tr v c im a l t nhin ca vng, trong iu kin c s vt cht hin nay nn pht trin cc ngh cu, ng thi nghin cu v tng bc ng dng loi ngh vy v r c thu ng, c chun Nghin cu nui lng trong cc vung, ng nh hoc cc hm o kn gi mt s i tng nh c m T chc khai thc mt s loi c san h c gi tr thm m v mt c th cao xut khu v cung cp cho cc c s du lch ni a. Ngun li rong bin Ngun li rong bin ca o cn b b ph bi v rong bin pht trin theo ma v, ch pht trin tt vo ma ng xun, b tn li vo ma h. pht trin v bo v ngun li rong bin c bit rong kinh t, cn p dng mt s bin php sau: C k hoch khai thc mt s loi rong kinh t thuc cc chi rong k ln, rong mu g, rong cu theo kiu thu ta tng t, ngun li c kh nng t phc hi. Cn nghin cu thnh phn dinh dng v cch ch bin mn rong gut lm thc phm thay rau xanh hay thc phm hp. cc nc ven Bin ng nh Philippine, Indonesia, Nht Bn, i Loan rong gut c ch bin bn trn th trng dng lm rau rt ph bin.

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Tiu lun: H sinh thi rn san h vng bin qun o Trng Sa thu hoch m bo pht trin bn vng. Ngun li ng vt y


Cn kho st nghin cu c th v sinh hc cho tng loi xy dng quy trnh

Cn nghin cu sinh hc, sinh trng ca cc loi ng vt y kinh t lm c s cho vic khai thc hp l, trnh khai thc qu mc ngun li lm mt cn bng sinh thi, dn nguy c tic ging nh hin nay. Khng khai thc t cc loi sinh vt qu him sng lu nm nh trai tai tng, tm hm, ra bin. cn c k hoch bo tn tt cc loi sinh vt ny. iu tra nghin cu cc loi sinh vt c cht hot tnh sinh hc lm thuc vn phong ph v a dng trn cc rng san h. Ch trc ht ti nhm san h mm, san h sng v hi min. Nghim cm cc phng thc khai thc mang tnh hy dit (cht n, cht c, kch in). Hn ch khai thc c sn trn rng san h bng th ln trnh nguy c cn kit ti nguyn. Tn dng cc ni yn sng trong cc lagun pht trin nui mt s loi hin c cng ngh nh ngc trai, tm hm, hi sm. Chim bin v ra bin: c k hoch bo v tuyt i chng, to khng gian thch hp cho chng quay li v trng duy tr v pht trin s lng qun n.

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