Skip to main content
Advanced Search

Filters: Tags: world-wide (X)

6 results (43ms)   

Filters
Date Range
Extensions
Types
Contacts
Categories
Tag Types
Tag Schemes
View Results as: JSON ATOM CSV
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.
thumbnail
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: Riparian buffers, the vegetated region adjacent to streams and wetlands, are thought to be effective at intercepting and reducing nitrogen loads entering water bodies. Riparian buffer width is thought to be positively related to nitrogen removal effectiveness by influencing nitrogen retention or removal. We surveyed the scientific literature containing data on riparian buffers and nitrogen concentration in streams and groundwater to identify trends between nitrogen removal effectiveness and buffer width, hydrological flow path, and vegetative cover. Nitrogen removal effectiveness varied widely. Wide buffers (.50 m) more consistently removed significant portions of nitrogen entering a riparian zone than...
Conclusions:Habitat heterogeneity is often perceived as fragmentation by certain species depending on spatial scales.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: Globally, the pattern of East/South-East Asian rice paddy belts have higher ecosystem/habitat diversity index values than Eurasian, American, and Australian wheat or corn belts. Thresholds/Learnings: Synopsis: The most critical of the issues faced in addressing the targets of the Convention of Biological Diversity are ‘biodiversity conservation under agricultural development’ and ‘the sustainable use of natural resources and/or land’. Therefore, appropriate indicators for the status of biodiversity and the pressures placed on biodiversity in relation to the intensification of agriculture are needed. Agricultural development has had major impacts on biodiversity and the abandonment of traditional land...


    map background search result map search result map Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.