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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: A review of the scientific literature describing the effects of linear developments on wildlife, especially large mammals, was provided. Of particular interest were the types of roads and linear developments created by the oil and pipeline industries in western Canada. The effects of linear developments (roads, powerline/pipeline rights-of-way, deforested strips) on wildlife were examined in the context of regional and landscape ecology. The review describes the different classes of linear disturbances, the various response categories for animal species and the impacts on species for the different classes. The review also provides potential mitigations and recommendations for landscape scale planning...
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Synopsis: Synthesizes information on a range of tools for reducing the footprint of human use, with an intended focus on public lands and associated natural resources. Implementation considerations and links to other resources are provided. Many tools are related either directly or indirectly to landscape patterns. For example, the section on “Disturbance Standards, Limits, or Thresholds” provides guidance and case study examples of pattern-based threshold establishment and implementation considerations in Alberta, California, and Australia. Many other Integrated Land Management tools outlined also relate directly or indirectly to landscape patterns and techniques for their management. Selected examples under the...
Conclusions:Generally, mimimum buffer widths may help maintain natural physical and chemical characteristics of resources whereas greater buffer widths may be required to maintain biological components of many wetlands and streams. Fixed width buffers do not consider site-specific conditions, and therefore may not adequately buffer aquatic resources. Variable width buffers, albeit more site specific and effective, are more expensive and offer less predictability for planning purposes.Thresholds/Learnings:Stream buffers should be a minimum of 15 to 30m in width to be effective in protecting the ecological integrity of wetlands and streams.
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Synopsis: One of the most important trends in biodiversity is the increase in the number of species as the land area increases. Botanists call this trend the species-area relationship, and it is one of the most dependable rules in biology. Many human activities on the landscape, influence species directly by disrupting their habitat, by removing other organisms upon which they may depend, or by injuring or killing them. Less direct, but in many cases equally as disruptive to the native species of an area, is the introduction of exotic species. In this study, data from published studies on flora over the last two centuries was used to produce contour maps of flora size and percentage of exotic species in North America...
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Conclusions: The negative effects of patch size and isolation on species may not occur until the landscape consists of less than 10% suitable habitat for birds, and 30% suitable habitat for mammals. Thresholds/Learnings: The negative effects of patch size and isolation on species may not occur until the landscape consists of less than 10% suitable habitat for birds, and 30% suitable habitat for mammals. Synopsis: This study involved a review of studies on birds and mammals in habitat patches in landscapes with different proportions of suitable habitat. The findings demonstrate that there exists a threshold in proportion of suitable habitat in the landscape, above which fragmentation becomes pure habitat loss....
Synopsis: This book provides important foundational concepts in landscape ecology, with a particular focus on the effects of land use and landscape fragmentation. Building on Forman’s patterns of landscape change, the book cites the McIntyre and Hobbs model of landscape change, which suggests that landscape modification often increases through time. Four broad classes of landscape condition can therefore be identified along a continuum of increasing human landscape modification: intact, variegated, fragmented, and relictual (figure 3). Similarly to Forman’s model, these classes represented correspond to different spatial patterns in the landscape. Therefore, as the extent of human land use increases, the amount...
Synopsis: This book addresses issues of landscape fragmentation and ecology emanating from the construction and use of roads. The text highlights ecosystem implications of this type of linear disturbance in relation to the following topics: · Roads, vehicles, and transportation planning · Vegetation and roadsides · Wildlife populations and collision mortality · Water, sediment, and chemical flows · Aquatic ecosystems · Wind, noise, and atmospheric effects · Road networks and landscape fragmentation Conclusions: Book addresses issues of landscape fragmentation and ecology emanating from the construction and use of roads. The text highlights ecosystem implications...
Conclusions:Habitat heterogeneity is often perceived as fragmentation by certain species depending on spatial scales.Thresholds/Learnings:
Conclusions:Document serves as a guide to consistent reporting for Alberta’s State of the Watershed Reports. It outlines a framework for reporting watershed conditions by providing specific criteria and direction to guide consistency in reporting. Framework includes major indicators of watershed health, including section on land cover and pattern indicators which provide critical thresholds for road density impacts to wildlifeThresholds/Learnings:Road density thresholds: grizzly bears- 0.4 km/km2; elk- 0.62 km/km2; black bears- 1.25 km/km2. Road densities for bull trout: 0.0-0.1 km/km2 = low risk; 0.1-0.2 km/km2 = moderate risk; 0.2-0.6 km/km2 = high risk; 0.6-1.0 km/km2 = very high risk; >1.0 km/km2 = extripation....
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:
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: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:
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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...
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...
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Synopsis: Species status assessments are often hindered by a paucity of demographic, abundance, or distributional data. Although extinction-risk correlates have been identified, their wide applicability may be compromised by differences in the variables examined, modeling technique, and phylogenetic or distributional scale. Here, we apply a common analytical approach to examine 14 possible extinction-risk correlates for mammals, fishes, and birds throughout Canada. Among mammals, risk is positively and strongly correlated with road density and age at maturity for land animals and weakly with body size for sea dwellers. Delayed maturity is of primary importance to predicting risk status in fishes, with small body...
    map background search result map search result map Environmental Trends in British Columbia 2002 Changing Patterns in the Number of Species in North American Floras. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review. Integrated Land Management Tools Compendium The Effects of Linear Developments on Wildlife: A Review of Selected Scientific Literature Correlates of Vertebrate Extinction Risk in Canada. Integrated Land Management Tools Compendium Environmental Trends in British Columbia 2002 The Effects of Linear Developments on Wildlife: A Review of Selected Scientific Literature Correlates of Vertebrate Extinction Risk in Canada. Changing Patterns in the Number of Species in North American Floras. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.