Land fragmentationn and impacts to streams and fish in the central and upper midwest
- Download PDF (880886)
- This publication is available only online.
In: Proceedings, Society of American Foresters 2000 national convention; 2000 November 16-20; Washington DC. SAF Publication 01-02. Bethesda, MD: Society of American Foresters: 38-44
Fragmentation of the land means changes in the vegetative cover. This alone has caused significant and wide spread physical and water quality changes to the streams and rivers in the central and upper Midwest. Removal of the forest canopy that changes land use to "open" conditions: agricultural, urban, or rights of way, is sufficient to initiate and prolong in-channel stream erosion and sedimentation for more than a Century. The comparison between cropland and forestland, shows the loss of forest cover will cause nearly annual, bankfull, peak flows to double or triple. The processes causing higher bankfull flows are synchronized snowmelt in open land and young-aged forestland and rapid delivery of rainwater from compacted soils. In contemporary forestlands, very high rates of harvesting can also increase bankfull flows. Where forestland is not fragmented, undersized road culverts, eroding road surfaces, and road washouts, are a significant source of sediment to streams. Both high velocities in culverts, high dams, and high bankfull stream velocities have fragmented the fish, invertebrate, and mussel communities of the Midwest. This paper considers how and where these impacts occur, and suggests riparian restoration measures to bring Midwest streams to their productive best.
KeywordsLand framentation, streams, fish, upper midwest, canopy, forest
Verry, Elon S. 2000. Land fragmentationn and impacts to streams and fish in the central and upper midwest. In: Proceedings, Society of American Foresters 2000 national convention; 2000 November 16-20; Washington DC. SAF Publication 01-02. Bethesda, MD: Society of American Foresters: 38-44