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LMM : year + fluctuation
Physical and chemical properties of groundwater
Wat
er le
vel (
cm)
Pre
cip
itat
ion
(m
m)
1970
1972
1975
1978
1982
1984
1992
1994
Un-mined H/S
Mid/Stable
Low/Fluctuate
High/F
Ground water level
Middle/F
Seasonal fluctuations
TN: high in young sitespH: low in unmined sites EC
pH
TN
(m
g/l)
TP
(m
g/l)
EC
(μ
S/
cm)
Year/month
Year/month
Year/month
Month
Month (2005) (Nishimura & Tsuyuzaki 2014)
Unmined site
Mined site Whole wetlands
-0.8 0.0 1.0 -0.8 0.0 1.0
1.0
0.0
-0.8
Small scale (mined site): WLM > WLR
Large scale: (mined site vs original site: pH > WLM > WLR
Scale-dependent environmental factorsMethodsPhysical elements = groundwater level (WLM) and the fluctuation (WLR)Chemical elements = chemical properties of ground water (pH, EC, TN, and TP)
1994 1992 1984 1982 1978 1975 1972 1970 Unmined
(Nishimura & Tsuyuzaki 2014)
Typhoons are sometimes disturbanceFelling of tees (wind) coastal wetlands, e.g., mangrove gap dynamicsSaltwater pulses (storm surge) push a wall of seawater inland increase in salinity → salt-intolerant species ↓
(Turner et al. 2006)
Most common tracks of hurricanes and typhoons
Areas of water with mean monthly temperatures above 27oC for at least one month of the year
Typhoons
Cyclone
Hurricane
Willy-willy
⇒ Predictable disturbance
Freshwater pulses (rain) raising river levels dilution of waterSediment redistribution (waves) developing river delta, etc.
Fig. 4.18 Delta grows as sediment accumulates at the mouth of a river, but once the river changes course, the delta gradually deteriorates into islands and offshore shoals. Storm and hurricanes play a significant role in reshaping the sediment (Peanland et al. 1988)
Regressive environments
Fresh marsh
Distributary
Beach ridges
Transgressive environments
Salt marsh marsh
Subaerial barrier
Subaqueous barrier
Sand sheet
Recurved spits
Shell reefs
Tidal inlet
Active delta
Stage 3Inner-shelf shoal
Stage 2Transgressive barrier
island arc
Stage 1Erosional headland with
flanking barriers
Restricted interdistributary
bay
Shoal base
Interdistributary bay
Erosional headland
Flankingbarrier island
Tidal inlet
Recurved spit
Shoal crest
Washover terrace
Recurved spit
Tidal inlet
Interdeltaic lagoon
Fig. There are many sources of sediment in coastal marshes: (a) resuspension of offshore shelf or lagoonal muds with landward transport during storms; (b) erosion of headlands or abandoned deltas with transport to marsh via longshore currents; (c) wave cutting of marsh muds exposed in lower shore face with transport to the marsh via longshore currents (c’); (d) riverine input; and (e) overwash redistribution (Michener et al. 1997)
UplandMarshBarrier/beach complexHolocene marsh muds
a
db
c’
c
e
Sediment produces a diverse array of wetland types
Seedbank
2,3983,254
14,7684,4966,405
SpeciesPrairie marshes Phragmites australis Carex spp. Coastal marshes Typha latifolia Myrica gale Mixed annuals
Table 4.1. Seedlings (/m2) emerged from seedbanks in meadows and marshes (Keddy 2010). The species found in Sarobetsu mire are listed.
= Buried reserves of viable seedsemerged after disturbances, such as wildfire (that improves nutrients, particularly phosphorus, and light (also reducing competition)
70-3,600826
38,25922,500
9,2002,324
Density of total speciesOpen waterWet meadowLakeshoreSandy small pondOrganic small pondBeaver pond
Fig. 4.13 Disturbance by muskrats (Ondatra zibethicus) and drought shift prairie potholes from one ecological state to another. (van der Valk & Davis 1978)
Marsh seed bank
Dry marsh
Regenerating marsh
Degenerating marshLake marsh
Mudflat emergent
Normal rainfall
Mudflat
Submersed and free floating
Muskrat damage
Emergent, submersed and free floating
SenescenceDiseaseInsectsHigh water
Submersed and free floating
Emergent, submersed and free floating
Submersed and free floating
Drought or drawdown
Fire severity affects vegetation and seed bank in a wetland
(Kimura & Tsuyuzaki 2011)
Fig 1. Similarities (%) between seed bank and the standing vegetation in each season and between seed bank in fall and summer. Upper and lower numerals show quantitative and qualitative similarities, respectively. Quantitative similarity is by Goodall’s index, and quantitative one is by Sørensen’s index. Thickness of lines connected with two circles indicates the intensity of similarities. Thick line > 80% in quantitative similarity; medium line: 2% to 15%, thin line: < 2%.
Vegetation, biomass and seed bank were monitored for the 2 yr after annual prescribed fires were discontinued in a reed swamp
Fire→ positive effects on seed bank dynamics→ developing diverse standing vegetation→ a tool to maintain species-rich wetlands
Seedling density (/m2)
Fall 2007
High35,300
Summer 2008
Less*43,638
High35,000
Less*27,088
* Sum of litter and soil layersDominant life form annuals/biennials – seedbank perennials - vegetation
Severe fire increased species diversity by providing short herbs (annuals) derived from seed bank
Vegetation
Relationships between vegetation and seedbank
Seedbank
Sp
ecie
s ri
chn
ess 8
6
4
2
0
Autumn 2006Fall 2007
BG RA MX MJ
Grassland
See
dlin
g d
ensi
ty (
/m2 )
2000
1500
1000
500
0
Fall 2006Summer 2007
BG RA MX MJ
Grassland
Cov
erag
e (%
) 80
60
40
20
0
Sp
ecie
s ri
chn
ess
12
10
8
6
4
2
0
LitterAbsent Present
(Egawa & Tsuyuzaki 2009)
Fall 2006 Summer 2007
Greenhouse experiment
Seedbank distribution
R. alba (0.75 mg)
M. japonica (1.21 mg)
P. australis (0.16 mg)
D. rotundifolia (0.01 mg)
Nu
mb
er o
f se
edlin
gs
G. triflora (0.12 mg)
litterpeat
Transient seedbank Fall → Summer: Decreased Their own sites
Fall → Summer: stable More in peat under litter Later successionalPersistent seedbank
BG RA MX MJ
Grassland
BG RA MX MJ
Grassland (Egawa & Tsuyuzaki 2009)
Seed germination and seedling survival
Winter
R. alba
M. japonica
P. communis
Days after sowing
Nu
mb
er
of
see
dlin
gs
Mixed grasslandBare groundMoliniopsis alba
grasslandRhynchospora alba
grassland
FL
(Egawa & Tsuyuzaki 2011)
ChinaBeijing
Lhasa
500 km
Shanghai
Yangtze River
Yellow River
Fig. 13.8 The Yangtze River is the third longest river in the world. It begins in the highland of Tibet, amidst some of the world’s largest high-altitude peatland (Ruoergai Peatland, bottom left; courtesy Wetlands International). Here it also flows through mountains which comprise one of the world’s biodiversity hotspots, the mountains of Southwest China (star, top left). Further east it passes through large lakes such as Dongting Lake (lower right). Where it enters the sea there are large deltaic wetlands. The largest dam, the Tree Geoges Dam, is indicated by the blue dot (top left).
ALOSPRISM, AVNIR-2April 14 2009
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