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Conclusions:Study found statistically significant relationships among source water quality, percent land cover, and drinking water treatment cost. Increased percent agriculture and urban cover were significantly related to decreased water quality, while decreased forest land cover was significantly related to decreased water quality. High percent land cover by non-forest vegetation was significantly related to low treatment cost.Thresholds/Learnings:
Conclusions:Report synthesizes scientific, planning, and policy-related aspects on the importance of land conservation in areas producing water for potable uses, including watersheds and aquifers. One critical finding indicated that if there is more forest cover in a watershed, water treatment costs are lower.Thresholds/Learnings:For every 10% increase in forest cover in the source area, treatment and chemical costs decreased by about 20%, up to about 60% forest cover. Treatment costs level off when forest cover is between 70-100%.
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Synopsis: Using multi-scale seasonal models, this study explored how broad scale landscape context and local resource heterogeneity influenced local resource selection among threatened forest-dwelling woodland caribou in southern Quebec. Caribou consistently avoided roads, however researchers identified thresholds in road proximity effects. The threshold distance at which caribou avoid roads is 1.25 km for active roads and 0.75 km from derelict roads. Open lichen woodlands were an important cover type for caribou during winter and spring, whereas deciduous forests, wetlands, and even young disturbed stands became important during calving and summer. Landscape cover type and amount explained more variation in habitat...
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Synopsis: This study analyzed the effects of vegetation change on hydrological fluctuations in the Columbia River basin over the last century using two land cover scenarios. The first scenario was a reconstruction of historical land cover vegetation, c. 1900. The second scenario was more recent land cover as estimated from remote sensing data for 1990. The results show that, hydrologically, the most important vegetation-related change has been a general tendency towards decreased vegetation maturity in the forested areas of the basin. This general trend represents a balance between the effects of logging and fire suppression. In those areas where forest maturity has been reduced as a result of logging, wintertime...
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Synopsis: Remotely sensed data and GIS were used to compare the effects of clear-cutting and road-building on the landscape pattern of the Bighorn National Forest, Wyoming. Landscape patterns were quantified for each of 12 watersheds on a series of four maps that differed only in the degree of clear-cutting and road density. Researchers analyzed several landscape pattern metrics for the landscape as a whole and for the lodgepole pine and spruce/fir cover classes across the four maps to determine the relative effects of clear-cutting and road building on the pattern of each watershed. At both the landscape and cover class scales, clear-cutting and road building resulted in increased fragmentation as represented...
Conclusions:Forest clearcutting differentialy affects birds of different ages. There is a threshold distance between reserves below which birds do not mind crossing clear cuts, making corridors more important as clearcut area and distance between forest reserves expandsThresholds/Learnings:
Conclusions:Results indicated that system and species-specific considerations are important when assessing the potential outcome of habitat loss and fragmentation on regional biotaThresholds/Learnings:
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Synopsis: Classical demographic methods applied to life history data on the northern spotted owl yield an estimate of the annual geometric rate of increase for the population of λ = 0.96 ± 0.03, which is not significantly different from that for a stable population (λ = 1.00). Sensitivity analysis indicates that adult annual survivorship has by far the largest influence on λ, followed by the probability that juveniles survive dispersal, and the adult annual fecundity. Substantial temporal fluctuations in demographic parameters have little effect on the long-run growth rate of the population because of the long adult life expectancy. A model of dispersal and territory occupancy that assumes demographic equilibrium...
Conclusions:Stream biotic integrity and habitat quality were negatively correlated with the extent of agriculture and positively correlated with extent of wetlands and forest.Thresholds/Learnings:
In the western United States, forest ecosystems are subject to a variety of forcing mechanisms that drive dynamics, including climate change, land-use/land-cover change, atmospheric pollution, and disturbance. To understand the impacts of these stressors, it is crucial to develop assessments of forest properties to establish baselines, determine the extent of changes, and provide information to ecosystem modeling activities. Here we report on spatial patterns of characteristicsof forest ecosystems in the western United States, including area, stand age, forest type, and carbon stocks, and comparisons of these patterns with those from satellite imagery and simulation models. The USD A Forest Service collected ground-...
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Conclusions: The amount of upstream impervious area affects downstream fish habitat quality, channel stability, and water quality. The use of riparian buffers can reduce the magnitude of urban impacts, however, they cannot fully mitigate the impacts of upstream development in the watershed. Threshold percentages of impervious areas , as well as the percentage of forest cover in a watershed appear to be the most effective indicators of watershed health. Thresholds/Learnings: Impervious areas should be kept at or below 10% of a watershed, and forest cover should be maintained at a minimum of 65% in order to effectively mitigate the impacts of urbanization and development on watersheds. Synopsis: This paper articulates...
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Conclusions: Reduction in landscape carrying capacity for wolf population distribution and viability depends largely on the degree of road density, public land ownership, amount of forest cover and high elk densities (another indicator of suitable habitat). Synopsis: This study employed two types of spatial models to evaluate the potential of wolf reintroduction in the southern Rocky Mountain region. A multiple logistic regression was used to develop a resource-selection function relating wolf distribution in the Greater Yellowstone region with regional-scale habitat variables. Researchers also used a spatially explicit population model to predict wolf distribution and viability at several potential reintroduction...
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Synopsis: This study attempts to build a forest fragmentation database for the conterminous United States by utilizing high-resolution NLCD data, roads, and a series of fragmentation indices that quantify forest landscape patterns. The paper outlines a methodology for assessing forest fragmentation and provides a comprehensive data set to be used as a base for further investigation at smaller scales. Conclusions: A forest fragmentation database for the conterminous United States was built to quantify forest landscape patterns nationwide. The paper outlines a methodology for assessing forest fragmentation and provides a comprehensive data set to be used as a base for further investigation at smaller scales. Thresholds/Learnings:...
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Conclusions: Marten capture rates were negatively correlated with increasing proximity of open areas and increasing extent of high-contrast edges. Forested landscapes were unsuitable for martens when the average nearest-neighbor distance between open, non-forested patches was <100m. Thresholds/Learnings: Synopsis: This study aimed to determine whether American marten abundance changed with incremental increases in habitat fragmentation caused by the combined effects of natural openings and timber clearcuts. Researchers evaluated differences in marten capture rates in 18 study sites with different levels of fragmentation. Martens appeared to respond negatively to low levels of habitat fragmentation, even with remaining...
    map background search result map search result map The influence of forest fragmentation and landscape pattern on American martens. Effects of land cover change on streamflow in the interior Columbia River Basin (USA and Canada). Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Forest fragmentation of the coterminous United States: assessing forest intactness through road density and spatial characteristics. Impacts of landscape change on wolf restoration success: planning a reintroduction program based on static and dynamic spatial models. Urbanization of aquatic systems: degradation thresholds, stormwater detection, and the limits of mitigation. Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Demographic models of the northern spotted owl (Strix occidentalis caurina) Urbanization of aquatic systems: degradation thresholds, stormwater detection, and the limits of mitigation. Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. The influence of forest fragmentation and landscape pattern on American martens. Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Demographic models of the northern spotted owl (Strix occidentalis caurina) Impacts of landscape change on wolf restoration success: planning a reintroduction program based on static and dynamic spatial models. Effects of land cover change on streamflow in the interior Columbia River Basin (USA and Canada). Forest fragmentation of the coterminous United States: assessing forest intactness through road density and spatial characteristics.