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Restoring Perennial Cover And Ecological Function To Corn Belt Landscapes: The Iowa Farmer's Perspective, Ryan C. Atwell, Lisa A. Schulte, Lynne M. Westphal Dec 2006

Restoring Perennial Cover And Ecological Function To Corn Belt Landscapes: The Iowa Farmer's Perspective, Ryan C. Atwell, Lisa A. Schulte, Lynne M. Westphal

Natural Resource Ecology and Management Publications

The tallgrass prairie ecosystem of the North American Corn Belt region has experienced major alteration of hydrologic systems, nearly complete loss of natural perennial vegetation, and concomitant decline in species due to agricultural intensification. In this working landscape, restoration to pre-European settlement conditions is doubtful. However, current research posits that restoring strategically placed patches of perennial cover across agricultural watersheds, such as stream buffers, wetlands and prairies, as well as instituting more diverse cropping rotations, could bolster current ecological function and enhance the conservation of species. These studies also suggest that such restoration might increase socio-economic resilience in the region ...


White-Tailed Deer Harvest From The Chronic Wasting Disease Eradication Zone In South-Central Wisconsin, Julie A. Blanchong, Damien O. Joly, Michael D. Samuel, Julia A. Langenberg, Robert E. Rolley, Janet F. Sausen Oct 2006

White-Tailed Deer Harvest From The Chronic Wasting Disease Eradication Zone In South-Central Wisconsin, Julie A. Blanchong, Damien O. Joly, Michael D. Samuel, Julia A. Langenberg, Robert E. Rolley, Janet F. Sausen

Natural Resource Ecology and Management Publications

Chronic wasting disease (CWD) was discovered in free-ranging white-tailed deer (Odocoileus virginianus) in south-central Wisconsin in 2002. The current control method for CWD in the state is the harvest of deer from affected areas to reduce population density and lower CWD transmission. We used spatial regression methods to identify factors associated with deer harvest across south-central Wisconsin. Harvest of deer by hunters was positively related to deer density (slope = 0.003, 95% C =0.0001-0.006), the number of landowners that requested harvest permits (slope = 0.071, 95% C/ = 0.037-0.105), and proximity to the area of highest CWD ...


Evaluating The Conceptual Tools For Forest Biodiversity Conservation And Their Implementation In The U.S., Lisa A. Schulte, Robert J. Mitchell, Malcolm L. Hunter Jr., Jerry F. Franklin, R. Kevin Mcintyre, Brian J. Palik Aug 2006

Evaluating The Conceptual Tools For Forest Biodiversity Conservation And Their Implementation In The U.S., Lisa A. Schulte, Robert J. Mitchell, Malcolm L. Hunter Jr., Jerry F. Franklin, R. Kevin Mcintyre, Brian J. Palik

Natural Resource Ecology and Management Publications

While much has been written describing biodiversity, its global decline, and the need for action, the scientific underpinnings guiding conservation practice have received little attention. We surveyed 10 large-scale forest management plans in the U.S. to establish which ecological concepts are commonly used to guide forest biodiversity conservation and evaluate the relative importance of these concepts in processes related to forest stewardship. We then reviewed the scientific literature to assess the degree to which these concepts are founded in antecedent ecological theory, the extent to which they have been tested, and the limits of those tests. We found that ...


Watershed Learning Activity: Coming To Terms With Geographic Scale, Tricia G. Knoot, Nancy Grudens-Schuck, Lisa A. Schulte Jun 2006

Watershed Learning Activity: Coming To Terms With Geographic Scale, Tricia G. Knoot, Nancy Grudens-Schuck, Lisa A. Schulte

Natural Resource Ecology and Management Publications

Want better dialogue in your watershed group? Proles may result from participants' misunderstanding of geographic scale. The Watershed Learning Activity can foster an understanding of the importance of geographic scale through group-based experiential learning that combines aerial photography and conceptual change theory. Try it at your next watershed meeting.


Changing Seasons: Weatherbirds, Stephen J. Dinsmore, Andrew Farnsworth Jan 2006

Changing Seasons: Weatherbirds, Stephen J. Dinsmore, Andrew Farnsworth

Natural Resource Ecology and Management Publications

The fall migration marks a transition between the breeding and non-breeding seasons. While some species, such as Mourning Dove, are still reproductively active well into autumn, most species that breed north of Mexico and the Caribbean have completed their primary breeding period, and those that migrate are making their way to wintering areas. The sojourn to nonbreeding sites includes some epic migrations, some of which are still being discovered--for example, the 11,000-km presumably non-stop flight of baueri Bar-tailed Godwits from coastal Alaska to New Zealand. Most species have much shorter flights, usually broken into segments, and other species reside ...


Habitat, Land Use, And Fish Assemblage Relationships In Iowa Streams: Preliminary Assessment In An Agricultural Landscape, Jeremiah D. Heitke, Clay L. Pierce, Gregory T. Gelwicks, Gregory A. Simmons, Gary L. Siegwarth Jan 2006

Habitat, Land Use, And Fish Assemblage Relationships In Iowa Streams: Preliminary Assessment In An Agricultural Landscape, Jeremiah D. Heitke, Clay L. Pierce, Gregory T. Gelwicks, Gregory A. Simmons, Gary L. Siegwarth

Natural Resource Ecology and Management Publications

Iowa leads the nation in percentage of land area converted to cropland, with a resulting negative impact on streams. We examined physical habitat, land use, and fish assemblage data from 37 second- to sixth-order stream sites, representing 7 of the 10 ecoregions within Iowa. Physical habitat conditions varied widely among sites, with sand dominating substrate composition. A nonmetric multidimensional scaling ordination of physical habitat variables suggested a pattern of among-site similarities defined by a stream size axis, an axis contrasting sites dominated by either woody or rocky fish cover, and an axis characterizing degree of riparian canopy coverage. Bluntnose minnow ...


Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart Jan 2006

Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart

Natural Resource Ecology and Management Publications

Macroinvertebrate and fish habitat is often degraded as a result of agriculture. Riparian buffer strips are commonly used to counteract the negative effects of agriculture in headwater streams. We assessed the relation of multi-aged riparian buffer strips to in-stream habitat, macroinvertebrate and fish assemblages in an Iowa stream. In-stream habitat, macroinvertebrates, and fish were sampled from two buffered sites and two unbuffered sites, with the greatest substrate, water depth, and velocity heterogeneity occurring in buffered sites. The highest macroinvertebrate richness (11) as well as fish species richness (14), diversity (1.99) and IBI score (37) were found in the site ...


Nitrogen Fertilization And Cropping System Impacts On Soil Quality In Midwestern Mollisols, Ann E. Russell, David Laird, Antonio P. Mallarino Jan 2006

Nitrogen Fertilization And Cropping System Impacts On Soil Quality In Midwestern Mollisols, Ann E. Russell, David Laird, Antonio P. Mallarino

Natural Resource Ecology and Management Publications

High grain production of corn (Zea mays L.) can be maintained by adding inorganic N fertilizer, and also by using crop rotations that include alfalfa (Medicago sativa L.), but the relative impact of these management practices on soil quality is uncertain. We examined the effects on soil of N fertilization rate (0, 90, 180, 270 kg ha−1, corn phase only) in four cropping systems: CC, continuous corn; CS, corn–soybean [Glycine max (L.) Merr.]; CCOA, corn–corn–oat (Avena sativa L.)–alfalfa; and corn–oat–alfalfa–alfalfa (COAA). The 23- and 48-yr-old experimental sites, situated in northeast (Nashua) and ...


Temperature Influences Carbon Accumulation In Moist Tropical Forests, James W. Raich, Ann E. Russell, Kanehiro Kitayama, William J. Parton, Peter M. Vitousek Jan 2006

Temperature Influences Carbon Accumulation In Moist Tropical Forests, James W. Raich, Ann E. Russell, Kanehiro Kitayama, William J. Parton, Peter M. Vitousek

Natural Resource Ecology and Management Publications

Evergreen broad-leaved tropical forests can have high rates of productivity and large accumulations of carbon in plant biomass and soils. They can therefore play an important role in the global carbon cycle, influencing atmospheric CO2 concentrations if climate warms. We applied meta-analyses to published data to evaluate the apparent effects of temperature on carbon fluxes and storages in mature, moist tropical evergreen forest ecosystems. Among forests, litter production, tree growth, and belowground carbon allocation all increased significantly with site mean annual temperature (MAT); total net primary productivity (NPP) increased by an estimated 0.2–0.7 Mg C·ha ...


The Freshwater Gastropods Of Iowa (1821-1998): Species Composition, Geographic Distributions, And Conservation Concerns, Timothy W. Stewart Jan 2006

The Freshwater Gastropods Of Iowa (1821-1998): Species Composition, Geographic Distributions, And Conservation Concerns, Timothy W. Stewart

Natural Resource Ecology and Management Publications

Although gastropods are important members of freshwater communities, the geographic range, ecological requirement, and conservation status of most species are poorly known. To advance this understanding, I used survey data from museums and peer-reviewed literature to summarize knowledge of the taxonomic composition and geographic distributions of freshwater gastropods in Iowa, U.S.A. Excluding records likely based on erroneous reports, 49 freshwater gastropod taxa (47 species and 2 genera with unknown numbers of species) inhabited Iowa during all or part of the period when records were collected (1821-1998). The Mississippi River and nearby tributaries of eastern Iowa and the prairie ...


Multi-Species Patterns Of Avian Cholera Mortality In Nebraska's Rainwater Basin, Julie A. Blanchong, Michael D. Samuel, Gene Mack Jan 2006

Multi-Species Patterns Of Avian Cholera Mortality In Nebraska's Rainwater Basin, Julie A. Blanchong, Michael D. Samuel, Gene Mack

Natural Resource Ecology and Management Publications

Nebraska’s Rainwater Basin (RWB) is a key spring migration area for millions of waterfowl and other avian species. Avian cholera has been endemic in the RWB since the 1970s and in some years tens of thousands of waterfowl have died from the disease. We evaluated patterns of avian cholera mortality in waterfowl species using the RWB during the last quarter of the 20th century. Mortality patterns changed between the years before (1976–1988) and coincident with (1989–1999) the dramatic increases in lesser snow goose abundance and mortality. Lesser snow geese (Chen caerulescens caerulescens) have commonly been associated with ...


Persistence Of Pasteurella Multocida In Wetlands Following Avian Cholera Outbreaks, Julie A. Blanchong, Michael D. Samuel, Diana R. Goldberg, Daniel J. Shadduck, Margaret A. Lehr Jan 2006

Persistence Of Pasteurella Multocida In Wetlands Following Avian Cholera Outbreaks, Julie A. Blanchong, Michael D. Samuel, Diana R. Goldberg, Daniel J. Shadduck, Margaret A. Lehr

Natural Resource Ecology and Management Publications

Avian cholera, caused by Pasteurella multocida, affects waterbirds across North America and occurs worldwide among various avian species. Once an epizootic begins, contamination of the wetland environment likely facilitates the transmission of P. multocida to susceptible birds. To evaluate the ability of P. multocida serotype-1, the most common serotype associated with avian cholera in waterfowl in western and central North America, to persist in wetlands and to identify environmental factors associated with its persistence, we collected water and sediment samples from 23 wetlands during winters and springs of 1996–99. These samples were collected during avian cholera outbreaks and for ...


Wetland Environmental Conditions Associated With The Risk Of Avian Cholera Outbreaks And The Abundance Of Pasteurella Multocida, Julie A. Blanchong, Michael D. Samuel, Diana R. Goldberg, Daniel J. Shadduck, Lynn H. Creekmore Jan 2006

Wetland Environmental Conditions Associated With The Risk Of Avian Cholera Outbreaks And The Abundance Of Pasteurella Multocida, Julie A. Blanchong, Michael D. Samuel, Diana R. Goldberg, Daniel J. Shadduck, Lynn H. Creekmore

Natural Resource Ecology and Management Publications

Avian cholera is a significant infectious disease affecting waterfowl across North America and occurs worldwide among various avian species. Despite the importance of this disease, little is known about the factors that cause avian cholera outbreaks and what management strategies might be used to reduce disease mortality. Previous studies indicated that wetland water conditions may affect survival and transmission of Pasteurella multocida, the agent that causes avian cholera. These studies hypothesized that water conditions affect the likelihood that avian cholera outbreaks will occur in specific wetlands. To test these predictions, we collected data from avian cholera outbreak and non-outbreak (control ...