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Wetlands. PA State Standard for Environment & Ecology 4.1.10.D & E. Wetlands:. An area that contains unique types of soil Home to plants adapted to the wet environment Contains water all year or at certain times of the year. . Common names for wetlands. A. Bog B. Swamps C. Marshes. A.
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Wetlands PA State Standard for Environment & Ecology 4.1.10.D & E
Wetlands: • An area that contains unique types of soil • Home to plants adapted to the wet environment • Contains water all year or at certain times of the year.
Common names for wetlands A. Bog B. Swamps C. Marshes A C B
Bog • A wetland in which soils consist of decomposed plant material. (peat/muck) • Dominant plants are the mosses • Other plants include: shrubs, evergreens, water lilies, cranberries, and blueberries
Bog • Very acidic (low pH), little O2 due the very little movement of water in or out. • Abundance of frogs, turtles, insects, some birds (usually no fish)
Swamp • Forested wetland • Dominated by trees & brushes • Soil drains slowly; rich in nutrients
Swamp • Classified depending on dominant tree type • Conifer Swamps ex: cedar, pines… • Hardwood Swamps ex. Maples, willows… • Deer, raccoons, herons, egrets, woodpeckers, snakes,frogs, turtles • Few fish
Marshes • Forms at the mouth of a river or in areas where there’s poor drainage • Rich in nutrients • Dominated by grasses, sedges, bulrushes, cattails • Beavers, frogs, turtles, raccoons, muskrats, birds, insects
PA wetlands; Chapter 105 of Commonwealth of PA code • “Those areas that are inundated or saturated by surface or groundwater 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…” • Are protected by the law.
There are 29 million acres of land area in PA. • 407,000 acres are classified as wetlands. Bonus What percentage is that of the whole? • Over 4,000 have been restored since 1990. 407,000/29,000,000 *100 = ? % 1.4%
PA’s classification of wetlands • Forested: • Mature woody trees over 20 feet tall. • Most abundant wetland in PA • 220,000 acres • Red & silver maples, green ash, black gums, river birches Bonus - What percentage is that of the whole? 220,000/407,000 *100= ? 54%
PA’s classification of wetlands • Scrub/shrub: • Trees less than 20 ft tall, • 2nd most abundant wetland in PA. • Alders, willows • 139,000 acres Bonus - What percentage is that of the whole? 34%
PA’s classification of wetlands • Emergent: • Marshy areas plants rooted in soil but emerge above water - 52,000 acres • Rushes, grasses, sedges Bonus - What percentage is that of the whole? 13%
Importance of Wetlands. • In the past, wetlands were mostly considered to be wastelands. As the United States was settled and people moved west, swamps and marshes were obstructions along the way. • Many were drained to be replaced by farmland, railroads and road construction.
Importance of Wetlands. • In recent decades many people have come to recognize the values of wetlands. • No longer the forgotten stepchild of our environment, some scientists call them natures kidneys because of the natural cleansing functions they perform.
Importance of Wetlands. • They provide rich habitat for a diverse range of plant and animal species • Protection from flooding and erosion. • Are also important to the nutrient cycle.
Functions of wetlands • Habitat • Food factories • Spawning grounds & nurseries • Cycling of nutrients • Buffer zones • Pollution control
Habitat • Home to bacteria, protists, plants and animals, including many threatened and endangered species • 35% of threatened and endangered species of the US • 500 of PA’s concerned plants • 80% of PA’s amphibians • 25% of all PA‘s reptiles • >120 species of birds
Food factories • High productivity rates due to large amount of plants
Food factories • High productivity rates due to large amount of plants • Food sources • Plants above the water • Decomposing plants below the water • These organisms that eat the plants provide food for all of the other organisms in the chain
Spawning grounds and nurseries • Amphibians, ducks, geese, swans, bitterns, and herons reproduce in wetlands • Large fish like walleye and bluegills that live in open water spawn in shallow water wetlands
Cycling nutrients • Plants drive this ecosystem through photosynthesis • Use CO2 and solar energy and convert it into O2 and food. • Autotrophs & Heterotrophs
Buffer Zones • Act as “natural sponges” to absorb excess runoff and slowly release it back into the environment • Store and slow water • Reduces flooding, runoff, and erosion
Pollution Control • Sediment is the primary water pollutant in PA • By slowing water flow, it reduces sediment by allowing it to settle out of the water. • Prevent air pollution • Plants store carbon rather than releasing it into the air
Loss of open space due to development causes negative effects • Reduce recreational areas • Less attractive to business • Reduce air and water quality • Increase flooding due to less vegetation and more concrete
Benefits of preserving wetlands • Improves air and water quality. Wetland plants improve air quality by removing harmful gases and contributing oxygen. They improve water quality by filtering out harmful substances from the water. • Provide habitat for wildlife • Lessen the chances and effects of flooding
Urban wetlands as a type of open space. • May be the remnants of streams and rivers left after development • Sometimes they result from planned or poorly planned development • Ex: drainage ditches and retention ponds. • Provide the following services: • Habitats for plants and animals • Buffer runoff • Trap and filter pollutants like iron and lead • Treat wastewater
No net loss. Regulation for development that stopped the loss of wetland acreage. If a wetland is destroyed, a new one needs to be made to compensate. Net gain The idea of restoring damaged wetlands and establishing new wetlands. Wetlands vs. Development
Factors that affect wetlands and watersheds • The major factor affecting US wetlands are human activities: • Agriculture • Urbanization & construction • Mining • Industry • Waste disposal
Effects of Agriculture Agricultural practices can disrupt or even destroy a wetland in different ways. • When food/resources are harvested. • Building drainage and irrigation ditches that divert water away. • Build-up of pesticides, fertilizers, nutrients, pathogens, and salts in wetland soils due to runoff. • Runoff of livestock waste and soil from erosion.
Urbanization and construction • Runoff carries many pollutants (sediments, wastes, pesticides, salts, heavy metals) from urban areas and construction sites. • Changing the natural flow of water decreasing the buffering ability of the wetland because it diverts the water away.
Mining Especially important in PA. • Acid drainage from both active and abandoned mines lowers the pH of wetlands which causes heavy metals to precipitate out. • Wetlands can filter out some of the pollutants but has limits.
Industry • New construction of office buildings, factories, and processing plants reduce wetland acreage • Both water intake and release of too much water can cause habitat loss or biodiversity loss. (ex. thermal pollution leads to algae blooms)
Waste disposal Another by-product of urbanization. • Solid waste at landfills leaking into wetlands. (most landfills are within a mile or less of wetlands) • Sludge and wastewater treatment effluent are sometime introduced to waterways and wetlands. • They are rich in nitrogen and phosphorus which leads to algal blooms.
PA’s Stream ReLeaf Program • A program launched in 1997 with several objectives: • Restore streamside buffers on private and public land. • Conserving streamside buffers to protect and improve forest diversity. • Educate the public about the importance of wetlands. • Develop activities to raise awareness of wetlands.
Natural Events that affect Wetlands. • Floods can have both a positive and negative effect on a wetland. • Erosion and sediment deposition can change the physical conditions of a wetland. • Drought reduces the volume of water in a wetland. • Fires can have positive and negative effects. • Global Climate Change – changes in climate affect the abundance of water. (too cold – decrease/too warm – increase)