Abiotic and Biotic Changes

    Abiotic and Biotic Changes

    The following table provides information on abiotic and biotic changes, how the ecosystems may respond and possible websites or organizations who can provide more information. 

    NOTE: Many of the impacts listed on the following pages appear to have mostly detrimental effects on the natural biota or ecosystem. Keep in mind, however, that humans often derive positive benefits from these same activities. For example, irrigation diversions allow agriculture to flourish in much of the west, and also may result in new riparian habitat forming along irrigation canals. The challenge to society is to find ways to minimize the impacts while retaining the benefits.

     

    Abiotic Change Ecosystem Response Websites to research for more information

    Stream channelization caused when stream banks are hardened with rip rap (rock or other materials along stream banks) or protected by berms.

    -Loss of habitat in the stream.
    -Increased velocity.
    -Changes in natural stream sinuosity.
    -Reduced fish and macroinvertebrate diversity from loss of spawning habitat, loss of macroinvertebrate habitats, or loss of flood fed side channels which are important for native fish reproduction.
    -Loss of riparian plants, and associated wildlife.

    		University of Wyoming Water Resources Data System Library 

    Pollutants entering the system from activities, including industrial
    discharges, agricultural runoff, improper cleanup of pet waste and
    over-fertilization of lawns.

    		-Loss of “beneficial uses” (such as recreation, irrigation, or aquatic habitat) of our natural waters due to increased
    pollution. May also change color and smell of water.
    -Loss of pollution sensitive species, replaced by pollution tolerant species.
    -Often fewer species (less diversity).
    -Health issues for humans using water for recreation or drinking.     		Food and Agriculture Organization of the United Nations (search for pollutants, runoff, fertilizer)

    Duluth Streams - Understanding Stream Impacts
    Construction of dams for irrigation, flood control, recreation. -Change in flow patterns throughout a year with fewer floods.
    -Change in temperature (surface of reservoirs become
    warmers, deeper waters remain cooler).
    -Change in sediment load (sediment settles to the bottom of reservoirs as the water velocity decreases).
    -Impacts on warm water fish if downstream temperature decreases, loss of native fish that depend on back channel flooding.
    -Clearer water downstream of dams may support salmonids and other sport fishes not found elsewhere in the river.     		Environmental Protection Agency
    (search for dams, irrigation, flood control)
    Development (increase an impervious surface area) -More pollution from urban runoff.
    -Less groundwater recharge.
    -Higher flows and more floods during rain events.
    -Loss of pollution sensitive species, replaced by pollution tolerant species.

    Raritan Basin Watershed Management Project (search for impervious surface area)

    Urban Stormwater (USU WQE)

    Climate Changes: Changes in runoff (rain event, snowmelt). Changes in maximum stream flow (big snow year).
    Drought.     		-Change in flows.
    -Loss of native fish if spawning areas silted in.
    -Possible bank erosion.
    -Change in sediment load.
    -Change in temperature.
    -Loss of habitat, impacts to coldwater fish as temperature increases, impacts to wildlife forage and cover.     		Environmental Protection Agency (climate change) 
    Mining oil, gas, and coal: Changes in groundwater movement and exposure of groundwater to pollutants, disturbance of surface, release of salty or polluted water to surface. -Pollution increase determined by mining operations.
    -Increased sediment runoff may occur from surface disturbance; water draining from mines may be extremely acidic and carry heavy metals; water discharged from coal bed methane wells can be very salty.
    -Loss of native fish if spawning areas silted in.
    -Sensitive species replaced by more tolerant species.     		Environmental Protection Agency (surface coal mining activities under clean water act)
    Biotic Changes Ecosystem Response Website for more information
    Introduced species to a stream or riparian area. -Depends on species.
    -Competition for food and habitat impacting native fish.
    -Uncontrolled growth of introduced species and other organisms.

    Environmental Protection Agency  (search for invasive species)

    Utah Department of Agriculture and Foods (search for nuisance species)

    Invasive Species (USU WQE)

    Loss of riparian area
    due to land use such as logging, urban landscaping, or grazing.     		-Loss of wildlife and bird habitat.
    -Increase in water temperature (reduced shading).
    -Increase in sediment load and pollutant runoff.
    -Impacts on coldwater fish as temperatures increase, loss of native fish if spawning areas are silted in.

    USDA/Forest Service
    (search for logging)

    Kansas State University
    (search for grazing)

    Human Influences that Affect Riparian Zones (USU WQE)