Why study aquatic ecology of the tropics?

Why study aquatic ecology of the tropics?

Pre

sen

ce

of

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tlan

ds

Northern Canada/Alaska

Continental U.S. EquatorialNeotropics

Nu

mb

er

of

we

tla

nd

sc

ien

tis

ts

Latitude distribution of wetlands based on Matthews and Fung (1987), global lakes and wetlands database (GLWD), and gross wetland map (redrawn from Lehner and Doll 2004)

Cuenca, Ecuador

Lago de Josephina

Lago de Josefina,Cuenca, Ecuador

Paraguay RiverDrainage BasinPantanal

The Pantanal

• 140,000 km2 of seasonally inundated floodplain

• West Central Brazil, Bolivia, Paraguay• Ecological sub-regions:

- - river corridors

- gallery forests

- - perennial wetlands and lakes

- - seasonally inundated grasslands

- - terrestrial forests

• Flora influenced by:

- - cerrado (central Brazil)- - chaco (Bolivia, Paraguay)- - Amazon

minimum

maximum

Source: Ponce 1995

Paraguay River at Ladario: Recorded seasonal max and min stages

Sta

ge

(c

m)

0

50

100

150

200

250

Dec Feb AprJu

nAug

Oct

Month

Rai

nfa

ll (m

m)

0

5

10

15

20

25

30

35

40

Tem

per

atu

re (

C)

Caiman yacare

Capped Heron: Pilherodius pileatus

Southern Screamer: Chauna torquata

Jabiru: Jabiru mycteria

Turquoise-fronted Parrot: Amazona a. aestiva

Hyacinth MacawAnodorhynchushyacinthinus

White-faced Capuchin: Cebus capucinus (not in Pantanal)

Piranha: Serrasalmus spiropleura

Water hyacinth:Eichhornia crassipes

Giant water lily:Victoria amazonica

Rooted water hyacinth:Eichhornia azurea

Cambara: Vochysia divergens

Environmental Threats in the Pantanal

• Agricultural development

• Mining

• Urban waste

• Navigation projects

• Poaching

• Tourism growth

Venha conhecer o maior e melhor hotel do Pantanal!

Paraguay-Paraná Hidrovía

• Would make the 3,440 km Paraguay-Paraná river system navigable year-round from Nueva Palmira (Uruguay) to Cáceres (Brazil).

• Would improve or construct the infrastructure needed to service the increased shipping capacity.

Timeline• A channelized waterway into the heart of South America is an old idea

and the Paraguay-Paraná have been navigated for many decades.

• Late 1980s: Intergovernmental Committee on the Hidrovía created to oversee the development of this waterway.

• 1990: Publication of an economic feasibility study.

• 1995-1997: Engineering, economic, and environmental assessments of the proposed project.

• 1990s: Cost-benefit “disputes”.

• 1998: Brazil halts plans for construction activities along the Brazilian portion of the waterway.

• Since 2000: Fate of Hidrovía remains uncertain and new plans are underway.

Remnant river channel

Channelized systemSource: South Florida Water Management District

Fortney et al. 2004

Sources: Schaller (1983), Hamilton (1999), Fortney and Gottgens (2005)

Sta

ge (

m)

Fazenda Ipiranga Fazenda Acurizal

4.0

4.5

5.0

5.5

6.0

0

10

20

30

Jan Mar May Jul Sep Nov3.0

4.0

5.0

6.0

7.0

0

5

10

15

20

Jan Mar May Jul Sep Nov

Pre

cip

itat

ion

(cm

)

Flooded area (km2) at low waterNo change Stage decrease

of 10 cmStage decrease

of 25 cm

NorthernPantanal

(3 subregions)8075 6887 (15%) 4782 (41%)

TotalPantanal

(8 subregions)12219 10785 (12%) 8385 (31%)

[Data from Hamilton, 1999]

Lateral Flood Pulse

Monthly distributions of annual flood peaks

0

10

20

30

40

50

Percent ofannual

flood peaks

Jan Mar May Jul Sep Nov

Cáceres Ladario Porto Murtinho

Source: Ponce (1995)

Longitudinal Flood Pulse

Economic benefits Environmental benefits

Sustainable development

? ?

BioScience, 2001