Browsing by Subject "Habitat degradation"

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    Quantifying parcelization potential of forest lands in Itasca County, north central Minnesota
    (University of Minnesota Duluth, 2009) Host, George E; Brown, Terry
    Land parcelization is one of several factors contributing to forest fragmentation, which in turn has been linked to numerous environmental degradations, including declines in water quality (Dillon et al., 1994), wildlife habitat (Brooks, 2003), and reduced access to public for hunting and recreational pursuits. Parcelization, the division of tracts of land into smaller holdings, is often accompanied by changes in ownership, land use/land cover and public access, and development. The increased trend toward divestiture of land holdings by forest product companies is well-documented in Minnesota and elsewhere. The Phase 1 report of the Minnesota Statewide Conservation and Preservation Plan identified habitat degradation, fragmentation, and consumptive use of land (conversion of land through development and associated infrastructure) as three of the main drivers of change affecting Minnesota’s land resources (Swackhamer et al 2007). Mundell et al (2007) recently completed an analysis of forest parcelization using land records from Itasca County. By using Minnesota Department of Revenue records from 1995 through 2006, they were able to identify subdivisions of ~40 acre parcels. They were also able to quantify changes in property tax classifications (e.g. forest undeveloped land to residential land), and assess the number and rate at which parcels were ultimately developed (changes in land value associated with presence of structures on the property). They found that parcelization rates for Itasca County were about 0.4% per year, or approximately half the typical rate of forest harvest (~1.0% per year). With the exception of 2002, when the elimination of Minnesota’s Tree Growth Tax Law caused a spike in the percentage of parcels classified as forest undeveloped land, the rate of parcelization has been relatively constant at 45-50 divisions per year across the county. There were strong spatial variations associated with parcelization. Parcelization was greatest near municipalities – high rates were observed near the cities of Grand Rapids and Deer River. Parcelization was positively associated with proximity to water and to public lands. The findings from this and other research provide a basis for a county-scale regional assessment of the relative potential for parcelization of private lands. The objectives of this study were to assess and map the relative potential for parcelization for private lands within Itasca County, related this to a critical habitat database developed as part of the Statewide Plan for Conservation and Preservation.
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    Railroad impacts on wetland habitat: GIS and modeling approach
    (Journal of Transport and Land Use, 2014) Mitra, Subhro; Bezbaruah, Achintya
    Deepor Beel is one of the most important wetlands in the Brahmaputra Valley of lower Assam in India and is representative of the wetlands found within the Burma Monsoon Forest biogeography region. Deepor Beel is a Wetland of International Importance under the Ramsar Convention and is contiguous with Rani and Garbhanga reserved forests. These forests house endangered Asiatic elephants (Elephas maximus) in addition to other birds and animals. The elephants depend on the wetland for water and food. Indian Railways con-structed Assam state’s southern railroad through the wetland in 2001. The railroad has fragmented the wetland into at least two subsystems and has segregated the wetland-forest ecosystem. Accelerated degradation of elephant habitat has been observed in the wetland since the railroad was constructed. Further, a number of elephants have died because of collisions with rail traffic. This study quantifies the impacts of the present railroad on the Deepor Beel ecosystem with special reference to Asiatic elephants. Geographic information systems (GIS) and mathematical models are used in impact quantification. The tools developed in this study can be used in analyses of similar ecosys-tems around the world.