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Conclusions: Book provides a comprehensive introduction to the principles and theories in landscape ecology. Early chapters introduce basic concepts and terminology that build a foundation for understanding more complex issues such as landscape disturbance dynamics, formulas and metrics for quantifying landscape patterns, and predictive models of landscape change. Thresholds/Learnings:
Conclusions:The effects of adjacent land-use on wetland sediment and water quality can extend over comparatively large distances. As such, sustaining high wetland water quality will not be achieved merely through the creation of narrow buffer zones between wetlands and more intensive land-uses, but rather by maintaining a heterogeneous regional landscape containing relatively large areas of natural forest and wetlands.Thresholds/Learnings:Water nitrogen and phosphorous levels were negatively correlated with forest cover at 2250m from the wetland edge. Sediment phosphorous levels were negatively correlated with wetland size and forest cover at 4000m from the wetland edge, and positively correlated with the proportion...
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Conclusions: In response to logging, songbirds demonstrated “habitat compensation” by moving into different adjacent habitats across a fragmented landscape. Thresholds/Learnings: Synopsis: This study investigates the degree to which species respond differently to logging across different scales in Alberta’s boreal mixed-wood forests. Researchers tracked changes in the composition and abundance of songbirds at the patch-level and landscape level, finding significant variation between the two spatial scales. The results suggest that predictions of organism response based on the island biogeographic model are limited, and that—while responses varied across species—songbirds demonstrated “habitat compensation” by moving...
Synopsis: This study tested the null hypothesis that densities of mammalian populations are constant over patches of varied size. In other words, performance as estimated by density does not covary with patch area. Researchers used a composite database from published studies and found that densities of 20 out of 32 species did not vary with patch area. Five species showed increasing density-area relationships and seven species showed decreasing density-area relationships. Landscapes comprised of smaller, less isolated patched tended to have negative density-area relationships and landscapes with large, more isolated patched tended to have positive density-area relationships. These results indicate that there are...
Conclusions:Results indicate that breeding bird species richness patterns significantly increased with fragment size. Area-sensitive species required patches of suitable habitat at least 5-55 ha in size. Edge and vegetation-restricted species were more affected by overall habitat loss of habitat than reductions in average patch size.Thresholds/Learnings:Area-sensitive species required patches of suitable habitat at least 5-55 ha in size, and regularly avoided smaller grassland fragments even when they were composed of suitable habitat
Conclusions:Presents condition and pressure indicators for land, water quantity, water quality, and aquatic and riparian systems, as a series of categorized indicators of environmental quality. These broadly include: land quality condition indicators, land use pressure indicators, water quantity pressure indicators, water quality pressure indicators, and indicators of aquatic and riparian ecosystem health.Thresholds/Learnings:
Conclusions:Higher percentages of forest cover within the watershed and within a 30m buffer were related to healthy fish communities and water quality, while near stream grasslands and urban land cover in the watershed contributed negatively to the health of fish communities and water quality.Thresholds/Learnings:High percentages of forest cover within a 30m riparian buffer were related to healthy fish communities and water quality. Fish density increased with increase in the average length of riparian vegetation without gaps (>30m).
Conclusions:Unsuitable habitat surrounding a patch of suitable habitat creates islands of high species density from which successful dispersion becomes difficult. Therefore, habitat surrounding a patch, rather than the quality of the patch itself, may be a more important determining factor of species abundance.Thresholds/Learnings:
Conclusions:Patch area was shown to be an important determinant of species richness irrespective of habitat heterogeneity. Isolation in space was also a significant factors in determining the degree of species richness in a grassland landscape.Thresholds/Learnings:
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Synopsis: The study examined the effects of road networks on suburbanizing ecosystems, using grassland bird distribution to explore the relative ecological importance of variables relative to linear disturbances and the effect of road traffic volumes. The study found that roads primarily affect ecological variables for 1) distance from road and 2) habitat patch size. The study also found that road traffic volumes are correlated to avian distribution, suggesting that traffic volumes have an ecological effect. The research suggests that traffic noise is the primary ecological effect of roads and that roads with higher traffic volumes extend the road effect zone outwards of 100 m and up to 1,200 m. Given the ecological...
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Conclusions: Soil texture, native prairie and grassland cover, and proximity to linear disturbances affect habitat suitability for burrowing owls. Native prairie coverage was considered the most critical variable in determining the most suitable habitat. The higher the percentage of native prairie, the more suitable it is for burrowing owl habitat.*Note that this study generated landscape level models with coarse variables, and the thresholds and values used may not be directly applicable to other areas or for site-specific analysis. Thresholds/Learnings: Synopsis: This report provides information on the habitat suitability requirements of the burrowing owl. Due to limited available data, the model that this...
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Conclusions: Presents environmental indicators for the purpose of guiding future planning efforts. These include 16 key indicators incorporating 64 separate measures highlighting the status and trends in environmental issues, as well targets to guide planning efforts. Thresholds/Learnings: Road density thresholds: Grizzly Bear 0.4km/km2; Black Bear 1.25km/km2; Elk 0.62 km/km2; and Bull Trout 0.1-1.31 km/km2 Synopsis: This document represents British Columbia’s third environmental indicators report, including 16 key indicators incorporating 64 separate measures highlighting the status and trends in environmental issues. The information is grouped into six theme areas: biodiversity, water, stewardship, human health...
Synopsis: This foundational text focuses on the distribution patterns of landscape elements that affect flows of animals, plants, energy, mineral nutrients and water in an ecosystem. The book also discusses the ecological implications of landscape change over time. The book introduces the important and well documented concepts of patches, corridors, and a background matrix and the building blocks of landscape (figure 4). The patch-corridor-matrix model is thus comprised of these three principle components which, together, constitute a landscape mosaic: Patches are “relatively homogenous non-linear areas that differ from their surroundings”. Corridors are “strips of a particular patch type that differ from the adjacent...
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Synopsis: This paper describes the spatial distribution of pH measurements from 60 sites distributed throughout the Kychlan River catchment, a 67km⊃2; boreal watershed in northern Sweden. Water samples were collected during a period of winter baseflow and during a spring flood episode. Chemical analyses included pH, Dissolved Organic Carbon (DOC), major cations (K, Mg, Na, Ca) and total filterable aluminum. Spring flood pH was shown to be highest in larger, lower altitude catchments underlain by fine sorted sediments, and lowest in small, higher altitude catchments underlain by a mixture of peat wetlands and forested till. There was also a trend with distance downstream of higher pH, acid neutralizing capacity and...
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Conclusions: The proportion of wetlands in the watershed at different scales affects dissolved organic carbon (DOC) concentrations in downstream lakes and rivers. Thresholds/Learnings: Synopsis: This study quantifies how the proportion of wetlands in the watershed at different scales affects dissolved organic carbon (DOC) concentrations in downstream lakes and rivers. Whether the watershed influence varies with season or hydrologic type of lake was also examined. The scaling and modelling approach used offered a useful way to examine heterogeneity of land cover types within the watershed and spatial arrangements, while allowing generality of conclusions with a large sample size. Zones of increasing distance from...
Conclusions:The paper describes the development and use of the Forest Water Quality Index (FWQI), an index to capture, evaluate and communicate the impact of forestry activities on water quality. The index is used to predict the water quality in watersheds anticipating future forestry activities by comparing data from similar watersheds that have already experienced forestry activities.Thresholds/Learnings:
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The study examined the effects of forest harvest practices that approximate natural disturbance processes to evaluate whether these practices help conserve biodiversity. Past research has shown that management practices that mimic natural disturbance events such as forest fires is a successful habitat conservation strategy, particularly for boreal forest bird communities. The study investigated how bird communities differed between postharvest and postfire stands in the mid-boreal region of Alberta. The research found that the most significant difference between postfire and postharvest landscapes is the amount and orientation of residual live and dead trees. Postfire stands consist largely of standing dead trees...
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Synopsis: Resource managers confronted with preserving ecosystems for prairie wetland birds in fragmented landscapes require landscape studies that direct conservation efforts over broad geographic regions. We investigated the role of local and landscape factors affecting habitat suitability by integrating remotely sensed wetland and land-cover data with wetland bird habitat models. We linked habitat models with locations of easement and fee-title wetlands to evaluate spatial location and extent of protected, suitable habitat. We also simulated impacts of the loss of small wetlands on suitability of larger wetlands for mobile species that use multiple wetlands. Lastly, we evaluated the efficacy of waterfowl habitat...
Synopsis: This book is the foundational text for understanding landscape ecology in terms of pattern/process relationships. Forman introduces the concept of “indispensible patterns” of habitat and habitat linkages that, if protected, can conserve the majority of important ecological function in a landscape. While all or specific attributes of an ecosystem may not be protected by these measures, the most important assets will retain their integrity if the essential general patterns are maintained. Forman’s Indispensable Landscape Patterns are related to both configuration and connectivity and fragmentation (figure 1). Forman suggests that the following patterns are indispensable in maintaining an ecologically viable...
map background search result map search result map Environmental Trends in British Columbia 2002 Fragments are not islands: patch vs landscape perspectives on songbird presence and abundance in a harvested boreal forest. Changes in bird communities in boreal mixedwood forest: harvest and wildfire effects over 30 years. Landscape indictors of human impacts to riverine systems Road traffic and nearby grassland bird patterns in a suburbanizing landscape. A landscape approach to conserving wetland bird habitat in the prairie pothole region of eastern South Dakota. Spatial heterogeneity of the spring flood acid pulse in a boreal stream network. Burrowing Owl Fragments are not islands: patch vs landscape perspectives on songbird presence and abundance in a harvested boreal forest. Road traffic and nearby grassland bird patterns in a suburbanizing landscape. A landscape approach to conserving wetland bird habitat in the prairie pothole region of eastern South Dakota. Changes in bird communities in boreal mixedwood forest: harvest and wildfire effects over 30 years. Spatial heterogeneity of the spring flood acid pulse in a boreal stream network. Environmental Trends in British Columbia 2002 Landscape indictors of human impacts to riverine systems