EXAM 3: Wetlands

What are examples of wetland ecosystems?

-swamps

-bogs, marshes, mires, fens

-stream/river edges (riparian zones)

What is a swamp?

a wetland whose dominant vegetation is trees and woody plants

What are marshes?

grasses + herbaceous plants are dominant. they have other forms of vegetation besides dominant woody plants.

Describe a bog or mire.

-Fed by rain/snow melt

-acidic (pH <7)

-poor soil

-location: enclosed depression

-plants can be carnivores

-can have very unique species

Describe fens.

-fed by groundwater

-alkaline/basic (pH >7)

-rich soil

-location: spring/seep

-contains sedges

Do all wetlands look "wet"? What is an example?

NO. not all wetlands look wet. wetlands do NOT have to be waterlogged year-round

-Example: Vernal Pool Wetland in northern California

What kind of ecosystems are wetlands?

they are dynamic ecosystems.

What are many wetland species adapted to?

many species are adapted to periodic saturation and drying.

What is an example of why wetland species are adapted to drying out?

Prairie Potholes in Northern Rocky Mountains

-the wetland is very wet in the spring, but very dry in the summer.

What kind of areas do wetlands often develop in?

wetlands often develop in areas where water table is at/near the surface.

What is the water table?

upper surface of groundwater below which soil is saturated with water that fills all voids.

What are the four ecological values of wetlands?

-high net productivity

-abundant & diverse wildlife (historically what they were known for)

-water quality improvement: traps sediment, filters pollutants, retain rain water

-flood and storm protection

What are wetlands identified by? Is this the same across the country?

they are identified by Field and Remote investigations (GIS) using 3 criteria.

-the details differ in the "formal definitions" from state to state

What are the 3 criteria that wetlands are identified by?

-wetland (hydric) soils

-hydrology

-wetland vegetations

What is the wetland soil like?

-H2O saturated in the soil for extended periods during the growing season.

-Soil O2 is rapidly depleted due to chemical and biological O2 demands

What does O2 being rapidly depleted from wetland soils cause?

anaerobic conditions.

-Lack of O2: many effects on biological and chemical processes in soil

What is mottling?

irregular spots or blotches of contrasting colors in the soil.

-this is a wetland soil characteristic

What are the typical H2O sources that serve a wetland?

-tidal flow

-precipitation

-groundwater seeps

-periodic flooding

What is a hydroperiod? what does it influence?

hydroperiod is a temporal pattern of H2O's fluctuation (regular or sporadic)

-strongly influences the type of wetland that's supported

What are hydrophytes? How are they classified?

they are plants in wetlands.

-classified according to probability of occurrence.

What are the three kinds of hydrophytes in wetlands?

-obligate wetland plants (OBL)

-facultative wetland plants (FACW)

-facultative plants (FAC)

What are obligate wetland plants (OBL)?

they have a high probability (>99%) of occurring in wetlands under natural conditions.

What are facultative wetland plants (FACW)?

usually occur (67-99%) in wetlands under natural conditions

What are facultative plants (FAC)?

sometimes occur (33-67%) in wetland environments under natural conditions

How many species of wetland plants are there in the U.S.? What are some examples?

roughly 7,000 species.

-Cattails, sedges, rushes, cordgrass, mangroves, water plantains

What are examples of carnivore plants in a wetland?

pitcher plants, venus fly trap (they live in nitrogen poor soils)

What do the specific adaptations of wetland plants allow them to do?

the specific adaptations allow them to outcompete Upland plants in saturated soils.

As land goes from wet to dry, what plants dominate?

OBL --> FACW --> FAC --> FACU --> UPL (upland)

What are the three broad categories for classifying wetlands?

Riverine

Palustrine

Lacustrine

Where are riverine wetlands found?

in a valley or adjacent to a stream channel. They lie in the active floodplain of a river or stream and have important links to the water dynamics of the river systems.

What are palustrine wetlands?

non-tidal wetlands substantially covered by emergent's, trees, shrubs, moss/lichens, etc. Total area is less than 20 acres. most bogs, swamps, marshes, and wet meadows fall into this category

What are lacustrine wetlands?

they are associated with deep water habitats with the following characteristics: situated in a topographic depression or a dammed river channel; lacking trees, shrubs, and other persistent emergents; total area exceeds 20 acres.

Whys is the determination of a wetland important?

what is & what is not a wetland is of significant ecological and economic importance.

What is delineation?

where the wetland is / is not

What do State and Federal laws require for wetland loss? What groups of individuals does this involve?

state and federal laws generally require compensation (mitigation) for wetland loss.

-Industry: regulators, scientists, lawyers, engineers

-Landowners, Politicians / judges & others influence this.

What was the definitions of a formal wetland in 1956?

"...lowlands covered with shallow and sometimes temporary or intermittent waters. they are referred to by such names as marshes, swamps, bogs, wet meadows, potholes, sloughs, and river-overflow lands."

What was the definition of a formal wetland in 1979?

"Wetlands are lands transitional between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water.... Wetlands must have one or more of the following three attributes: 1) at least periodically, the land supports predominantly hydrophytes, 2) the substrate is predominantly undrained hydric soil, and 3) the substrate is non-soil and is saturated with water or covered by shallow water at some time during the growing season of each year."

What was the definition of a formal wetland in 1984?

"....those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs and similar areas."

What was the definition of a formal wetland in 2000?

"Wetlands are ecosystems that arise when inundation by water produces soils dominated by anaerobic processes and forces the biota, particularly rooted plants, to exhibit adaptations to tolerate flooding"

What are the principles of a wetland?

no net loss

type for type

preference for onsite mitigation

regulatory approval

What are jurisdictional wetlands?

meets the 3 criteria (hydric soils, hydrology, wetland plants) as established by the U.S. Army Corps of Engineers (USACE)

What is section 404?

Clean Water Act, 1972

"discharged or dredged or fill material into waters of the United States, including wetlands"

What is section 10?

Rivers and Harbors Acts, 1899

"Work or structures in or affecting navigable waters"

What are activities that may be regulated to protect wetlands?

-draining an agricultural wetland

-installation of a water control structure

-dredging in a wetland

-highway construction in a wetland

Wetlands are the most common?

the most commonly altered habitats

What causes the loss and degradation of wetlands?

Agricultural, residential, or business

-installing drain tile

-a dredging operation

-extensive coastal development

The USA has a significant loss of?

wetlands

The states have what percentage of wetlands?

the individual states range from <1% to roughly 43% wetlands (AK)

Which state has the most wetlands?

Alaska

-Some states have roughly 90% loss of wetlands

Describe the percentage of wetland in Alabama.

AL reduced by 1/2 in the last ~200 years.

-occupies ~10% of the area in the state (Mobile-Tensaw River Delta)