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Habitat Improvement (habitat + improvement)
Selected AbstractsRiver Enhancement in the Upper Mississippi River Basin: Approaches Based on River Uses, Alterations, and Management AgenciesRESTORATION ECOLOGY, Issue 3 2007T. Kevin O'Donnell Abstract The Upper Mississippi River is characterized by a series of locks and dams, shallow impoundments, and thousands of river channelization structures that facilitate commercial navigation between Minneapolis, Minnesota, and Cairo, Illinois. Agriculture and urban development over the past 200 years have degraded water quality and increased the rate of sediment and nutrient delivery to surface waters. River enhancement has become an important management tool employed to address causes and effects of surface water degradation and river modification in the Upper Mississippi River Basin. We report information on individual river enhancement projects and contrast project densities, goals, activities, monitoring, and cost between commercially non-navigated and navigated rivers (Non-navigated and Navigated Rivers, respectively). The total number of river enhancement projects collected during this effort was 62,108. Cost of all projects reporting spending between 1972 and 2006 was about US$1.6 billion. Water quality management was the most cited project goal within the basin. Other important goals in Navigated Rivers included in-stream habitat improvement and flow modification. Most projects collected for Non-navigated Rivers and their watersheds originated from the U.S. Department of Agriculture (USDA). The U.S. Army Corps of Engineers and the USDA were important sources for projects in Navigated Rivers. Collaborative efforts between agencies that implement projects in Non-navigated and Navigated Rivers may be needed to more effectively address river impairment. However, the current state of data sources tracking river enhancement projects deters efficient and broad-scale integration. [source] Stream Restoration in the Upper Midwest, U.S.A.RESTORATION ECOLOGY, Issue 4 2006Gretchen G. Alexander Abstract Restoration activities intended to improve the condition of streams and rivers are widespread throughout the Upper Midwest, U.S.A. As with other regions, however, little information exists regarding types of activities and their effectiveness. We developed a database of 1,345 stream restoration projects implemented from the years 1970 to 2004 for the states of Michigan, Ohio, and Wisconsin in order to analyze regional trends in goals, presence of monitoring, spatial distribution, size, and cost of river restoration projects. We found that data on individual projects were fragmented across multiple federal, state, and county agencies, as well as nonprofit groups and consulting firms. The most common restoration goals reported for this region were in-stream habitat improvement, bank stabilization, water-quality management, and dam removal. The former two were most common in Michigan and Wisconsin, where salmonid fisheries enhancement appeared to be an important concern, whereas water-quality management was most frequent in Ohio. The most common restoration activities were the use of sand traps and riprap, and other common activities were related to the improvement of fish habitat. The median cost was $12,957 for projects with cost data, and total expenditures since 1990 were estimated at $444 million. Over time, the cost of individual projects has increased, whereas the median size has decreased, suggesting that restoration resources are being spent on smaller, more localized, and more expensive projects. Only 11% of data records indicated that monitoring was performed, and more expensive projects were more likely to be monitored. Standardization of monitoring and record keeping and dissemination of findings are urgently needed to ensure that dollars are well spent and restoration effectiveness is maximized. [source] Exploring the interactions between flood defence maintenance works and river habitats: the use of River Habitat Survey dataAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2009Gemma L. Harvey Abstract 1.More extensive physical management of rivers in response to increasing flood risk, and action to improve the ecological quality of rivers represent two major, and potentially conflicting, challenges. 2.Improved understanding of the interactions between flood defence works and habitat structure must be achieved in order to satisfy both of these demands in the context of flood risk management and habitat improvement. 3.This paper examines the ,extensive' and ,intensive' use of data derived from a standardized method of assessing habitat character to explore the effects of flood risk maintenance works on river habitat quality. 4.Analysis of the UK River Habitat Survey (RHS) data set reveals some broad trends towards reduced habitat heterogeneity associated with recent flood defence works such as dredging and weed-cutting. 5.These observations correspond with published localized experimental work and suggest that the RHS database can be a useful resource for identifying relationships at relatively broad scales. 6.Applying the RHS methodology at finer spatial scales for sites experiencing continuing maintenance reveals contrasting results and highlights some key methodological issues; these include the availability and selection of high quality benchmark conditions, the legacy of past management, lag times associated with maintenance and recovery, and recording of marginal habitat features. 7.Small modifications to the RHS method could enable calculation of more detailed habitat indices while maintaining comparability with the national dataset. 8.If the issues identified in this paper can be addressed or accounted for, RHS could be an important tool for assessing the relationship between flood defence management and new statutory obligations for ecological improvement. Copyright © 2009 John Wiley & Sons, Ltd. [source] Plant species response to land use change ,Campanula rotundifolia, Primula veris and Rhinanthus minorECOGRAPHY, Issue 1 2005Regina Lindborg Land use change is a crucial driver behind species loss at the landscape scale. Hence, from a conservation perspective, species response to habitat degradation or improvement of habitat quality, is important to examine. By using indicator species it may be possible to monitor long-term survival of local populations associated with land use change. In this study we examined three potential indicator (response) species for species richness and composition in Scandinavian semi-natural grassland communities: Campanula rotundifolia, Primula veris and Rhinanthus minor. With field inventories and experiments we examined their response to present land use, habitat degradation and improvement of local habitat quality. At the time scale examined, C. rotundifolia was the only species responding to both habitat degradation and improvement of habitat quality. Neither R. minor nor P. veris responded positively to habitat improvements although both responded rapidly to direct negative changes in habitat quality. Even though C. rotundifolia responded quickly to habitat degradation, it did not disappear completely from the sites. Instead, the population structure changed in terms of decreased population size and flowering frequency. It also showed an ability to form remnant populations which may increase resilience of local habitats. Although P. veris and especially R. minor responded rapidly to negative environmental changes and may be useful as early indicators of land use change, it is desirable that indicators respond to both degradation and improvement of habitat quality. Thus, C. rotundifolia is a better response species for monitoring effects of land use change and conservation measures, provided that both local and regional population dynamics are monitored over a long time period. [source] | ||||||||||