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Restoration Activities (restoration + activity)
Selected AbstractsUsing Remote Sensing to Evaluate the Influence of Grassland Restoration Activities on Ecosystem Forage Provisioning ServicesRESTORATION ECOLOGY, Issue 4 2009Carolyn M. Malmstrom Abstract As valuation of ecosystem goods and services derived from ecological processes becomes increasingly important in environmental decision-making, the need to quantify how restoration activities influence ecosystem function has grown more urgent, particularly within income-generating or subsistence-providing landscapes where economic needs and biodiversity goals must be balanced. However, quantification of restoration effects is often hindered by logistical issues, which include (1) the difficulty of systematically monitoring responses over large areas and (2) lack or loss of comparison sites necessary for assessing treatment effect. We explored the use of remote sensing to quantify the effects of native grass seeding and prescribed burns on ecosystem forage provisioning services within a California (U.S.A.) rangeland landscape. We used Landsat time series to monitor forage (green biomass) dynamics within 296 ha of treatment areas,distributed throughout a 36-km2 watershed,for 6 years and to identify post hoc comparison areas when a priori comparisons were lacking. Remote sensing analysis documented gains and losses in forage provisioning services due to restoration efforts and provided critical information for adaptive management. Our results demonstrate the degree to which invaded grasslands can be resistant to change and suggest that increasing the functional complexity of restoration mixes might help increase forage availability and reduce opportunities for weed reinvasion. [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] VegTrack: A structured vegetation restoration activity databaseECOLOGICAL MANAGEMENT & RESTORATION, Issue 2 2009Andre Zerger Summary, Information about on-ground vegetation restoration activities (e.g. fencing and revegetation) is critical if natural resource management (NRM) groups are to monitor progress towards restoration targets, assess the efficacy of their interventions and adaptively learn from different actions. However, in Australia, there are few practical guidelines for recording data, making it difficult to consistently compare actions between sites and through time. Records of primary information are particularly important given the ongoing national investment in vegetation restoration activities. With the aid of six-case study areas in different landscapes, robust guidelines and tools were developed and incorporated into VegTrack, a methodology, which allows groups to develop their own vegetation restoration activity database. VegTrack differentiates spatial data from attribute data storing each in different databases (a GIS and a relational database management system respectively). We describe the process which enables NRM groups to develop their own database, and provide a Microsoft Access 2003 version of VegTrack to allow NRM groups to commence activity recording. To demonstrate the utility of the VegTrack method in different situations and to encourage consistency across study areas, we describe the application of the guidelines for several scenarios including riparian revegetation, corridors disrupted by roads and infill plantings. [source] Copper toxicity thresholds for important restoration grass species of the western United States,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2002Mark W. Abstract Copper toxicity thresholds for plant species that are used in restoration activities in western North America have not been established. As a result, ecological risk assessments must rely on toxicity thresholds established for agronomic species, which usually differ from those of species used in restoration. Thus, risk assessors have the potential for classifying sites as phytotoxic to perennial, nonagronomic species and calling for intensive remediation activities that may not be necessary. The objective of this study was to provide a better estimate of Cu toxicity thresholds for five grass species that are commonly used in restoration efforts in the western United States. We used a greenhouse screening study where seedlings of introduced redtop (Agrostis gigantea Roth.), the native species slender wheatgrass (Elymus trachycaulus [Link] Gould ex Shinners var. Pryor), tufted hairgrass (Deschampsia caespitosa [L.] Beauvois), big bluegrass (Poa secunda J. Presl var. Sherman), and basin wildrye (Leymus cinereus [Scribner&Merrill] A. Löve var. Magnar) and the agricultural species common wheat (Triticum aestivum L.) were grown in sand culture and exposed to supplemental concentrations of soluble Cu of 0 (control), 50, 100, 150, 200, 250, and 300 mg/L. We determined six measures of toxicity: the 60-d mean lethal concentration (LC50), 60-d mean effective concentration (EC50)-plant, 60-d EC50-shoot, 60-d EC50-root, phytotoxicity threshold (PT50)-shoot, and the PT50-root. Results suggest that these restoration grass species generally have higher Cu tolerance than agronomic species reported in the past. Of the species tested, redtop appeared to be especially tolerant of high levels of substrate and tissue Cu. Values of EC50-plant for restoration grasses were between 283 and 710 mg Cu/L compared to 120 mg Cu/L for common wheat. Measured PT50-shoot values were between 737 and 10,792 mg Cu/ L. These reported thresholds should be more useful for risk assessors than those currently used, which are based largely on agronomic crops. [source] Habitat-mediated size selection in endangered Atlantic salmon fry: selectional restoration assessmentEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 4 2010Michael M. Bailey Abstract Preservation of adaptive variation is a top priority of many species restoration programs, but most restoration activities are conducted without direct knowledge of selection that might foster or impair adaptation and restoration goals. In this study, we quantified geographic variation in selection on fry size of endangered Atlantic salmon (Salmo salar) during the 6-week period immediately following stocking in the wild. We also used a model selection approach to assess whether habitat variables influence patterns of such selection. We found evidence for significant size-selection in five out of six selection trials. Interestingly, the strength and pattern of selection varied extensively among sites, and model selection suggested that this variation in phenotypic selection was related to geographic variation in the presence of large woody debris and the slope of the stream gradient. The strong selection differentials we observed should be a concern for endangered salmon restoration, whether they reflect natural processes and an opportunity to maintain adaptation, or an indicator of the potentially deleterious phenotypic consequences of hatchery practices. [source] Competitive relationships of Andropogon gerardii (Big Bluestem) from remnant and restored native populations and select cultivated varietiesFUNCTIONAL ECOLOGY, Issue 3 2004D. J. GUSTAFSON Summary 1Although genetic differentiation among plant populations is well known, its relevance for preserving the integrity of native ecosystems has received little attention. In a series of competition experiments with Andropogon gerardii Vitman, a dominant species of the North American Tallgrass Prairie, plant performance was related to seed provenance and restoration activities. 2Glasshouse experiments showed plant performance to be a function of seed source. Differential target plant performance relative to competitor identity was observed when plant performance was assessed across a range of competitor densities. Local and non-local plants were larger when competing against non-local plants relative to the local and cultivar plants, while cultivar plants were consistently larger than local and non-local plants regardless of competitor identity or density. The consistency of cultivar performance could reflect directional selection during cultivar development for consistently high fecundity, vigorous vegetative growth and resistance to pathogens. 3In a field experiment, non-local plants were half the size of local and cultivar plants, supporting recognition of seed provenances of A. gerardii based on differences in plant performance among source populations observed in the glasshouse study, and previous genetic analyses of the same populations. 4This study establishes that seed provenance and restoration activities influence the competitive ability of a dominant species which, in turn, may affect plant community structure and potential ecosystem function. [source] Spatiotemporal dynamics of evapotranspiration at the Glacial Ridge prairie restoration in northwestern MinnesotaHYDROLOGICAL PROCESSES, Issue 7 2006Assefa M. Melesse Abstract Among the various indicators of success in wetland restoration, hydrology is the most important and relatively easy to monitor. Evapotranspiration (ET) was used to assess the ecohydrologic changes at the Glacial Ridge prairie restoration site in northwestern Minnesota. Twelve Landsat images from 2000,03 for the months of June, July and August were used to study the spatial ET changes. Spatial monthly and seasonal ET were estimated using a surface energy budget technique from Landsat images. Five sub-basins within the study area were delineated to represent the different conditions of the wetlands. Their spatial and temporal ET responses to the restoration activities (native species planting, burning and ditch closures) were studied. Spatial statistics showing mean and standard deviation of monthly ET were computed. Comparisons were made between these watersheds and the preserved sub-watershed of the study area. The average annual ET increases for the five sub-basins were in the range of 9% (2002,03) to 25% (2001,02). Over the study period, ET increased by nearly 50%. After considering the effect of variations in precipitation, wind speed and solar radiation on the resulting ET, the results show that ET increased in recent years as result of the restoration activities. Copyright © 2005 John Wiley & Sons, Ltd. [source] STATEWIDE EMPIRICAL MODELING OF BACTERIAL CONTAMINATION OF SURFACE WATERS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2006James D. Wickham ABSTRACT: Bacterial contamination of surface waters is attributed to both urban and agricultural land use practices and is one of the most frequently cited reasons for failure to meet standards established under the Clean Water Act (CWA) (P.L. 92,500). Statewide modeling can be used to determine if bacterial contamination occurs predominantly in urban or agricultural settings. Such information is useful for directing future monitoring and allocating resources for protection and restoration activities. Logistic regression was used to model the likelihood of bacterial contamination using watershed factors for the state of Maryland. Watershed factors included land cover, soils, topography, hydrography, locations of septic systems, and animal feeding operations. Results indicated that bacterial contamination occurred predominantly in urban settings. Likelihood of bacterial contamination was highest for small watersheds with well drained and erodible soils and a high proportion of urban land adjacent to streams. The number of septic systems and animal feeding operations and the amount of agricultural land were not significant explanatory factors. The urban infrastructure tends to "connect" more of the watershed to the stream network through the creation of roads, storm sewers, and wastewater treatment plants. This may partly explain the relationship between urbanization and bacterial contamination found in this study. [source] DEVELOPMENT AND EVALUATION OF MULTIPLE-OBJECTIVE DECISION-MAKING METHODS FOR WATERSHED MANAGEMENT PLANNING,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2002France Lamy ABSTRACT: Making decisions for environmental management is a complex task due to the multiplicity and diversity of technological choices. Furthermore, the exploitation of natural resources and the preservation of the natural environment imply objectives that are often in conflict within a sustainable development paradigm. Managers and other decision makers require techniques to assist them in understanding strategic decision making. This paper illustrates the use of a multiple-objective decision-making methodology and an integrative geographical information system-based decision-making tool developed to help watershed councils prioritize and evaluate restoration activities at the watershed level. Both were developed through a multidisciplinary approach. The decision-making tool is being applied in two watersheds of Oregon's Willamette River Basin. The results suggest that multiple-objective methods can provide a valuable tool in analyzing complex watershed management issues. [source] Using Remote Sensing to Evaluate the Influence of Grassland Restoration Activities on Ecosystem Forage Provisioning ServicesRESTORATION ECOLOGY, Issue 4 2009Carolyn M. Malmstrom Abstract As valuation of ecosystem goods and services derived from ecological processes becomes increasingly important in environmental decision-making, the need to quantify how restoration activities influence ecosystem function has grown more urgent, particularly within income-generating or subsistence-providing landscapes where economic needs and biodiversity goals must be balanced. However, quantification of restoration effects is often hindered by logistical issues, which include (1) the difficulty of systematically monitoring responses over large areas and (2) lack or loss of comparison sites necessary for assessing treatment effect. We explored the use of remote sensing to quantify the effects of native grass seeding and prescribed burns on ecosystem forage provisioning services within a California (U.S.A.) rangeland landscape. We used Landsat time series to monitor forage (green biomass) dynamics within 296 ha of treatment areas,distributed throughout a 36-km2 watershed,for 6 years and to identify post hoc comparison areas when a priori comparisons were lacking. Remote sensing analysis documented gains and losses in forage provisioning services due to restoration efforts and provided critical information for adaptive management. Our results demonstrate the degree to which invaded grasslands can be resistant to change and suggest that increasing the functional complexity of restoration mixes might help increase forage availability and reduce opportunities for weed reinvasion. [source] Restoration Ecology and Invasive Riparian Plants: An Introduction to the Special Section on Tamarix spp. in Western North AmericaRESTORATION ECOLOGY, Issue 1 2008Patrick B. Shafroth Abstract River systems around the world are subject to various perturbations, including the colonization and spread of non-native species in riparian zones. Riparian resource managers are commonly engaged in efforts to control problematic non-native species and restore native habitats. In western North America, small Eurasian trees or shrubs in the genus Tamarix occupy hundreds of thousands of hectares of riparian lands, and are the targets of substantial and costly control efforts and associated restoration activities. Still, significant information gaps exist regarding approaches used in control and restoration efforts and their effects on riparian ecosystems. In this special section of papers, eight articles address various aspects of control and restoration associated with Tamarix spp. These include articles focused on planning restoration and revegetation; a synthetic analysis of past restoration efforts; and several specific research endeavors examining plant responses, water use, and various wildlife responses (including birds, butterflies, and lizards). These articles represent important additions to the Tamarix spp. literature and contain many lessons and insights that should be transferable to other analogous situations in river systems globally. [source] Settlement and Survival of the Oyster Crassostrea virginica on Created Oyster Reef Habitats in Chesapeake BayRESTORATION ECOLOGY, Issue 2 2007Janet A. Nestlerode Abstract Efforts to restore the Eastern oyster (Crassostrea virginica) reef habitats in Chesapeake Bay typically begin with the placement of hard substrata to form three-dimensional mounds on the seabed to serve as a base for oyster recruitment and growth. A shortage of oyster shell for creating large-scale reefs has led to widespread use of other materials such as Surf clamshell (Spisula solidissima), as a substitute for oyster shell. Oyster recruitment, survival, and growth were monitored on intertidal reefs constructed from oyster and Surf clamshell near Fisherman's Island, Virginia, U.S.A. and on a subtidal Surf clamshell reef in York River, Virginia, U.S.A. At the intertidal reefs, oyster larvae settlement occurred at similar levels on both substrate types throughout the monitoring period but higher levels of post-settlement mortality occurred on clamshell reefs. The oyster shell reef supported greater oyster growth and survival and offered the highest degree of structural complexity. On the subtidal clamshell reef, the quality of the substrate varied with reef elevation. Large shell fragments and intact valves were scattered around the reef base, whereas small, tightly packed shell fragments paved the crest and flank of the reef mound. Oysters were more abundant and larger at the base of this reef and less abundant and smaller on the reef crest. The availability of interstitial space and appropriate settlement surfaces is hypothesized to account for the observed differences in oyster abundance across the reef systems. Patterns observed emphasize the importance of appropriate substrate selection for restoration activities to enhance natural recovery where an underlying habitat structure is destroyed. [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] Lessons from primary succession for restoration of severely damaged habitatsAPPLIED VEGETATION SCIENCE, Issue 1 2009Lawrence R. Walker Abstract Questions: How can studies of primary plant succession increase the effectiveness of restoration activities? Can restoration methods be improved to contribute to our understanding of succession? Results: Successional studies benefit restoration in six areas: site amelioration, development of community structure, nutrient dynamics, species life history traits, species interactions, and modeling of transitions and trajectories. Primary succession provides valuable lessons for understanding temporal dynamics through direct, long-term observations on severely disturbed habitats. These lessons assist restoration efforts on infertile or even toxic substrates. Restoration that uses scientific protocols (e.g., control treatments and peer-reviewed publications) can offer insights into successional processes. Conclusions: A century of studying successional dynamics has provided modern restoration activities with many useful lessons that are not being fully utilized. [source] | |||||||||||||