Wetland

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How can water levels be measured periodically in the field?

staff gauge

Where are wetlands more abundant?

sub-tropical regions, temporate, and boreal regions

Saturated (non-tidal)

substrate saturated for extended during growing season

In the US, what is the number one cause of wetland loss and deterioration?

Drainage- particularly agriculture- 87%

Characteristics of soils

- acidic (produce rotten egg odor) -high in organic matter, anaerobic conditions slow decomposition, so wetland soils often have a thick layer of organic litter -organic matter decays into a material called humus -muck soils display a black color from large quantities of organic matter -occurs carbonic acid -large amounts of clay (high cation exchange capacity)

4. property of soil is soil moisture potential

- measures the water content -has 3 important conditions: saturation, field capacity, and permanent wilting point. These define the available water and drainable porosity

What is a hydrograph?

- one way to study water budget over time, -it depicts changes in a wetland's depth over time, -important for studying and classifying wetlands (reveals information about hydroperiod)

How have humans negatively impacted wetlands?

-Dredging and stream channelization -Deposition of fill material -Diking and damming -Levees -Tilling for crop production (soil erosion) -Mining (peat mining) -Construction -Industrial operations -Runoff -Air and water pollutants -Changing nutrient levels -Introducing nonnative species -Grazing by domestic animals

What are natural causes of wetland loss and deterioration?

-Erosion, -Succession (over time lakes fill in with sediments and it forms an upland type of habitat), -Droughts, -Hurricanes and other storms

Compare terrestrial wetland and deep water

...

What are examples of phytoplankton?

-algae

What do aerenchyma do?

-allow for exchange of gases, -grow in inundated soils

What do floating leaves do?

-allow plants to adapt to fluctuating water levels in a wetland and do not become submerged

Geographical distribution of tidal saltwater marshes are found where?

-along intertidal shores in middle and high latitudes -Bay of Fundy -New England -Coastal Plains (florida) -fewer in western North America because of rugged shores and powerful waves

6. property of soil is soil horizons

-as soils develop they naturally form strata called horizons -O horizon: litter layer that contains organic matter such as leaves -A horizon: the topsoil layer, mineral soil mixed with some organic matter -B horizon: the subsoil layer, predominantly mineral soil- combination of parent material and accumulations from upper layers -C horizon: mineral soil, little affected from soil processes (no accumulation of minerals or material from upper layers) -R horizon: bedrock, such as sandstone, limestone, or granite

What are pannes?

-bare, exposed, or water-filled depressions near coast -high salinity -lack in vegetation because the soils are too salty -has green cyanobacteria

What are different examples of emergent hydrophytes?

-cattail, -sedge, -bulrush, -pennywort, -alligator weed, -pickeral weed, -smartweed

What are the different examples of submergent hydrophytes?

-coontail -american pondweed -hydrilla

3. property of soil is porosity

-describes the number, size, and connectedness of soil pores (or air spaces) -determined in part by texture, with larger particle sizes generally leading to more porous soils -determined in part by compaction -directly affects water and air availability, and therefore the chemical processes that occur there (soil moisture potential)

What are pneumatophores?

-erect roots that protrude above water marked soils and enable the plant to transport oxygen, -important to saturated soils

What is the hydrology of a tidal flat?

-frequently flooded -low elevation -contains no vegetation

Chemistry of tidal freshwater marshes

-generally organic sediments -soils of near neutral pH

Ecosystem Functions of tidal freshwater marshes

-high productivity -energy flow: primarily detrital- generally, organic production is decomposed to litter and peat; nutrients are extracted and recycled -can be nutrient sinks, transformers, or sources depending on the situation -often located close to major cities and offer metal accumulation -support a wide variety of life: invertebrates, many fish, birds, reptiles, amphibians, and mammals

5. property of soil is soil color

-measure hue, chroma, and value; indicator of different properties as it is influenced by organic matter, minerals, and water content -measured using a Munsell chart

What are some hydrophyte adaptations?

-multiple or buttressed tree trunks, -pneumatophores or knees, -Adventitious roots (water roots), -Dangling root systems, -Specialized tissues, such as aerenchyma, -floating leaves

What is a tidal saltwater marsh?

-natural or semi natural halophytic grassland on alluvial sediments bordering saline water bodies whose water level fluctuates tidally

What is reduction?

-occurs when soils are releasing oxygen, or when they are deficient in oxygen -wetlands show signs of reduction -soils appears wet and gray

Vegetation of tidal freshwater marshes

-often vary diverse, many emergents -zonation is not as apparent as in tidal saltwater marshes but sometimes forms -Atlantic Coast: low marsh: sedges, rushes, Spartina spp high marsh: cattails, spartina, smartweed -Gulf Coast Delta: levees: black willow cattail marshes also a variety of interior flats: Eleocharis

What is hydrophytic vegetation?

-plant-life that thrives in wet conditions -the sum total of macrophytic plant life that occurs in areas where the frequency and duration of inundation or soil saturation produce permanently or periodically saturated soil of sufficient duration to exert a controlling influence on the plant species present (US Army Corps of Engineers 1987)

What is anaerobic conditions?

-the complete lack of oxygen in the soil because pores are saturated with water -cause stress to plants since roots need oxygen to function (prevents respiration) -characterized by a lack of oxygen and lead to different chemical processes in the soil

What are the different examples of floating hydrophytes?

-water lettuce -water hyacinth -duck weed

What are the classes of hydrophytes?

-woody,-trees and shrubs, -emergent,-stem both above and below the water surface, -submergent, -stem below water surface, -floating,-at the surface (roots not in soil), -phytoplankton,-microscopic

What are the functions of wetlands?

1) stabilize water supplies and prevent flooding, 2) downstream receivers of water and waste, 3) clean pollutant waters, protect shorelines, recharge ground water

What are hydrological impacts?

1. a wetland's particular hydrological regime leads to a unique vegetation assemblage 2. primary productivity and other ecosystem functions are often enhanced by flowing conditions and a pulsing hydroperiod; often stagnated by unvarying conditions 3. accumulation of organic material in a wetland is controlled by hydrology through its influence on primary productivity, decomposition, and the import/export of organic matter 4. nutrient cycling and availability are significantly influenced by a wetland's hydrology

Distinguishing characteristics

1. depth and duration of flooding varies considerably from wetland to wetland 2. water levels fluctuate from season to season and year to year, so boundaries cannot be easily determined by identifying the presence of water 3. wetlands are located at the margins between aquatic and terrestrial systems 4. wetlands species range from those with adaptations to either wet or dry conditions (facultative) or those adapted only to a wet environment (obligate) 5. wetlands vary widely in size, from potholes to large expanses 6. their geographic location can vary greatly, ranging from far inland to coastal and from rural to urban 7. the degree to which they are impacted by human activity is also quite variable

What are ecosystem functions of tidal saltwater marshes?

1. highly productive- tides bring nutrients and flush toxins; high NPP 2. Major detrital pathway: fungi aerobic and anaerobic bacteria break down detritus; detritus is organic materials from living things that is no longer alive; composed of dead or decaying plants 3. Algae (food for many organisms) 4. support numerous consumers

What are the two zones of salt marsh?

1. low marsh- flooded almost daily, contains primarily spartina alterniflora 2. high marsh- flooded irregularly by higher than normal tides; at higher elevations, contains Juncus, Spartina petens, (some shorter specimens of Spartina alterniflora)

3 broad types of tidal freshwater marshes

1. mature marshes- old, with a well-developed peat 2. floating marshes- broken loose from substrate, now float; mostly in gulf coast region 3. new marshes- occur in prograding deltas in the gulf; form where rivers build deltas

What are the three basic characteristics of wetlands?

1. presence of shallow water or an inundated ground surface, 2. hydric soils, 3. hydrophytes

Adaptations plants have to flooding and salinity in tidal saltwater marshes

1. salt glands that removes excess salt from water taken into the plant osmotically 2. aerenchyma- allows air to reach the water parts of aquatic plants 3. relatively long rhizomes that allow the plant to quickly colonize new areas

What are tidal saltwater marshes influenced by?

1. soil-water salinity- influenced mostly by tide frequency but also soil texture, drainage, slopes, and freshwater inflow 2. nutrients- primarily nitrogen limited; when sulfides are exposed, they turn to sulfuric acid which causes a low pH

What are hydrological functions of wetlands?

1. water storage (for flood control, drinking water supply, wetland soils are usually high in organic matter which absorbs many times its weight in water, spongy feel) 2. improve water quality (filter pollutants and eroding sediments, wetland vegetation often uptake and store chemical pollutants, since water often flows slowly in a wetland sediments often settle to the bottom trapping them. Some wetlands are used to treat storm water and waste water) 3. recharge surface and ground water supplies 4. the unique hydrology of wetlands can support a diversity of animals

When was the time of major wetland loss?

1950's-1970's

What percentage of US has wetland loss?

53%

What is the geographic extent of mangrove swamps?

Along tropical and subtropical coastlines throughout the world; In FL 10,000 islands is one of the best extents in the world.

How are mangroves swamps characterized?

By halophytic trees, shrubs, and other plants growing in brackish or saline tidal waters.

Why are wetlands called nature's supermarket?

Highly productive ecosystem and provide a unique habitat and supports a large variety of plants and animals

Wetland is considered to be what organ?

Kidney

What are the five categories of hydrophytes?

OBL, FACW, FAC, FACU, UPL

Who defined wetlands as treaty between many countries, defined wetlands more broadly, have water up to 6 m deep

Ramsar Convention (Navid 1989)

Who defined wetlands as areas inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and under normal circumstances due, a prevalence of vegetation adapted for life in saturated soil conditions

US Army Corps of Engineers (as related to Clean Water Act)

Who defined wetlands as lands transitional between terrestrial and aquatic ecosystems or covered by shallow water. Characterized by presence of hydric soil, hydrophytes, non-soil substrate saturated or covered by shallow water

US Fish and Wildlife Service (in Cowardin et al. 1979)

Who defined wetlands as lowlands with shallow and sometimes temporarily/intermittent water with the development of moist-soil vegetation

US Fish and Wildlife Service Circular 39 (by Shaw and Fredine 1956)

Hydrology of tidal freshwater marshes

influenced by tides (but inland enough not to receive saltwater)

What is a halophyte?

a plant that grows in water in high salinity coming into contact with saline water through its roots or by salt spray

What is a halophyte?

a plant that grows in water of high salinity coming into contact with saline water through it's roots or by salt spray.

What is a hydric soil?

a soil that formed under conditions of saturation, flooding, or ponding long enough during the growing season to develop anaerobic conditions in the upper part

What is tidal freshwater marshes?

a type of wetland that is close enough to coasts to experience tides but above the reach of ocean saltwater

What have wetlands been lost to?

agriculture

How much loss has occurred between 2004 and 2009?

an estimated 62,300 acres

What is precipitation?

any form of water, such as rain, snow, sleet, hail, or mist, that falls from the atmosphere and reaches the ground

How do plant species vary in their ability to tolerate flooded conditions?

by the amount, frequency, and duration control the types of vegetation that will grow

How is a hydroperiod termed in wetlands?

hydrological signature

1. property of soil is composition

composition-soils are composed of four major components: mineral, organic matter, water, air (pores)

What is evapotranspiration?

describes the loss of water to the atmosphere (evaporation) and the loss due to transpiration by plants

When do adventitious roots occur?

during prolonged soil saturation

What is the standard definition of wetlands

ecosystems that have all three of these characteristics: 1. water, 2. hydric soils, 3. hydrophytes

Facultative (FAC)

equally likely to occur in wetlands or non wetlands (estimated probability 34-66%)

Regularly flooded (tidal)

flooded and exposed daily

Semipermanently flooded (non-tidal)

flooded during growing season of most years

Temporarily flooded (non-tidal)

flooded for brief periods during growing season

Seasonally flooded (non-tidal)

flooded for extended period of growing season, usually dry by the end of the growing season

Irregularly flooded (tidal)

flooded less often then daily

Permanently flooded (non-tidal)

flooded throughout the year

Intermittently flooded (non-tidal)

flooded throughout year, except in extreme drought

What is also linked to wetlands?

ground water

Upland (UPL)

occur almost always (estimated probability>99% under natural conditions) in non wetlands

Obligate (OBL)

occur almost always (estimated probability>99%) under natural conditions in wetlands

Geographical distribution of tidal freshwater marshes

occur where rivers meet the coast; in the US:Atlantic and Northern Gulf coast

What is oxidation?

occurs during oxygen uptake by soils, or when they are rich in oxygen

When making a wetland determination and/or delineation, where is emphasis placed?

on the total assemblage of dominant macrophytic plant species

In the 1600's, in the lower 48 states, how many wetlands existed?

over 220 million

Subtidal (tidal wetlands)

permanently flooded with tidal water

What are the basic processes of the hydrological cycle?

precipitation, surface water flow, groundwater flow, evapotranspiration, and tides

Irregularly exposed (tidal wetlands)

surface exposed by tides less often than daily

2. property of soil is texture

texture- determined by the relative proportions of mineral particles -texture classes defined using the textural triangle

What is the field capacity?

the amount of water remaining in the soil a few days after having been wetted after free drainage has ceased. The plants available water, or holding capacity, is the portion of water that can be absorbed by plant roots. By definition is the amount of water available, stored, or released between field capacity and the permeant wilting point water contents

What do hydrological processes directly control?

the formation, size, persistence, and function of a wetland

What is a hydroperiod?

the seasonal pattern of water levels in a wetland, specifically -How deep? -How often does it flood? -What is the duration of flooding?

What is permanent wilting point?

the water content of the soil when most plants such as corn, wheat, and sunflowers growing in that soil wilt and fail to recover their turgor upon rewetting

What can influence surface water flow in wetlands?

tides (typically in coastal areas)

What is buttressed mean?

tree trunk is excessively swollen compared to the height of the usual water mark

Facultative Upland (FACU)

usually occur in non wetlands (estimated probability 67-99%), but occasionally found in wetlands (estimated probability 1-33%)

Facultative wetland (FACW)

usually occur in wetlands (estimated probability 67-99%), but occasionally found in non wetlands (estimated probability 1-33%)

What provides a basis for understanding these hydrological processes of a wetland?

water budgets

Where are wetlands?

wetlands are widely distributed across the planet, covering 4-6% of land surface

What are hydroperiods used to classify?

wetlands into different hydrological types of water regimes

Where is surface water supplied to?

wetlands through normal streamflow, flooding from lakes and rivers, overland flow, ground-water discharge, and tides

When does saturation occur?

when the soil pores hold the maximum amount of water and plants cannot uptake any more water either

What are tidal creeks?

where water depth fluctuates with tides


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