Wetlands Part 2

wetland loss

varies greatly; has slowed in more recent years

AL has

3 million acres of wetlands

functions of wetlands

• contaminants (stores water, sponge) and sediments are filtered

• carbon sinks (CO₂ absorbers)

• groundwater flow

• wildlife habitat

reasons why wetlands are “valuable” ecosystems

• water filtration

• water storage

• protect shorelines (tidal marshes, mangroves)

• wildlife habitat (unique spp.)

• global climate stabilizers (carbon sinks)

water filtration

‘kidneys of the landscape;’ remove pollutants, nutrients, etc.

water storage

1. minimize floods (1 acre: 1-1.5 mil gal floodwater) loss = increased risks)

2. recharge aquifers with purified water

wetlands help

minimize flooding

• flood control and damage reduction by capturing, storing, and slowly releasing water

• especially in mangroves and tidal marsh

hurricanes

reduce wave energy and inland flooding depths

wetlands a key to

bird diversity

• ~80% USA bird spp. occupy wetlands at some point in their life history; migratory waterfowl ($$$)

prairie potholes

~50% of duck ‘production’

2 key federal laws for bird protection

• Migratory Bird Treaty Act (1929)

• Migratory Bird Conservation and Stamp Act (1933)

  • these laws were passed during Great Depression to protect any bird that migrates

migratory flyways

there are 4:

• pacific

• central

• mississippi

• atlantic

ducks unlimited

formed following federal laws

• buy up wetlands and conserve them (16 mil)

Conservation Reserve Program (1985)

USDA Farm Service Agency voluntary program

• removes farmland from production in exchange for yearly rental payments (10-15 year contracts)

• part of farm bill?

long term goals of CRP

improve H₂O quality, prevent soil erosion, and develop wildlife habitat

currently enrolled in CRP

~22 million acres

Farmable Wetlands Program

restores previously farmed wetlands and buffer

isolated wetlands

not connected to each other or to other bodies of water by vegetated corridors or buffers, through which wildlife can easily disperse

wildlife populations

may be enhanced by managing for wetland complexes

wetland complexes

networks of interconnected wetlands

vernal pools

key wildlife habitats for many amphibian and reptile species — adapted to using seasonal seasonal wetlands as breeding/nursery habitat, particularly (fills in spring/winter, dry in summer)

• unique species contained there

• mole salamanders (tiger, spotted, marbled)

• spring peepers, cricket frogs

riparian forested wetlands

along stream/river

utility riparian forested wetlands

highly productive, temporary (decreased predation risk), avoids competition w adults

constructed wetlands

help reduce water pollution, increase water supply, and protect the environment; a tool for water treatment (wastewater, storm runoff)

1. physical

2. chemical

3. biological

physical

filtration, evaporation, sedimentation

chemical

precipitation, chemical decomposition (UV)

biological

bacterial metabolism, uptake/utilization by plants

constructed wetlands takes

much longer than treatment plants to clean water

slackwater darter (Ethesoma boschungi)

• discovered in 1968 by Dorothy Sentz and Charles Gooch (UNA students)

• described by Wall and Williams in 1974, grad students at UA and named in honor of H. Boschung (= A in ichtyology)

• others had collected them, but no “lightbulb”

slackwater darters depend

on spring seeps; are doubly vulnerable

• disjunct distributions; federally threatened (endangered)

  • potential for extirpation this century

  • wetland dependent

slackwater darters habitat

requires 2 distinct habitats:

• non-breeding: pools of small streams with organic debris

• breeding (winter): seepage areas (pasture, partly wooded or wooded) with wet weather springs — subject to weather (drought)

  • “lift” required to reach seepage across intermittent streams

  • many areas tiled/drained for pasture or converted to ponds

stream → seepage

predator free

research on slackwater darters

species has much genetic structure among populations (high site fidelity); salmon

key cave

there is an AL cavefish that is federally endangered

wetland functions

ecosystem services provided by wetlands

values for wetlands

economic estimates of importance/worth of > 1 of a wetland’s functions to society

1. $ sale of fish and wildlife from wetland

2. $ from tourism

3. public support

most wetland viewed

as “wastelands” for most of 20th century