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421.
Human-induced global climate change presents a unique and difficult challenge to the conservation of biodiversity. Despite
increasing attention on global climate change, few studies have assessed the projected impacts of sea-level rise to threatened
and endangered species. Therefore, we estimated the impacts of rising sea levels on the endangered Lower Keys marsh rabbit
(Sylvilagus palustris hefneri) across its geographic distribution under scenarios of current conditions, low (0.3-m), medium (0.6-m), and high (0.9-m)
sea-level rise. We also investigated the impacts of allowing vegetation to migrate upslope and not allowing migration and
of two land-use planning decisions (protection and abandonment of human-dominated areas). Not surprisingly, under all simulations
we found a general trend of decreasing total potential LKMR habitat with increasing sea-level rise. Not allowing migration
and protecting human-dominated areas both tended to decrease potential LKMR habitat compared with allowing migration and abandoning
human-dominated areas. In conclusion, conservation strategies at multiple scales need to be implemented in order to reduce
the impact of global climate change on biodiversity and endangered species. At the regional level, managers must consider
land-use planning needs that take into account the needs of both humans and biodiversity. Finally, at the local scale those
agencies that are in charge of endangered species conservation and ecosystem management need to rethink static approaches
to conservation or else stand by and watch ecosystems degrade and species go extinct. This can be accomplished by bioclimatic
reserve systems where climatically underrepresented areas are included in conservation planning along with the standard concerns
of threat, opportunity, connectivity, and viability. 相似文献
422.
Kjelland ME Kreuter UP Clendenin GA Wilkins RN Wu XB Afanador EG Grant WE 《Environmental management》2007,40(2):231-244
Fragmentation of family-owned farms and ranches has been identified as the greatest single threat to wildlife habitat, water
supply, and the long-term viability of agriculture in Texas. However, an integrative framework for insights into the pathways
of land use change has been lacking. The specific objectives of the study are to test the hypotheses that the nonagricultural
value (NAV) of rural land is a reliable indicator of trends in land fragmentation and that NAV in Texas is spatially correlated
with population density, and to explore the idea that recent changes in property size patterns are better represented by a
categorical model than by one that reflects incremental changes. We propose that the State-and-Transition model, developed
to describe the dynamics of semi-arid ecosystems, provides an appropriate conceptual framework for characterizing categorical
shifts in rural property patterns. Results suggest that changes in population density are spatially correlated with NAV and
farm size, and that rural property size is spatially correlated with changes in NAV. With increasing NAV, the proportion of
large properties tends to decrease while the area represented by small properties tends to increase. Although a correlation
exists between NAV and population density, it is the trend in NAV that appears to be a stronger predictor of land fragmentation.
The empirical relationships established herein, viewed within the conceptual framework of the State-and-Transition model,
can provide a useful tool for evaluating land use policies for maintaining critical ecosystem services delivered from privately
owned land in private land states, such as Texas. 相似文献
423.
The Kathmandu Valley in Nepal has experienced a very rapid increase in population resulting in considerable land use/land
cover change and also a series of environmental problems. One of the results of the population increase is an expansion of
brick manufacturing within the Valley because most structures are brick. The brick kilns are intense in several locations
of the Valley and have an interesting pattern of using the same lands for bricks during the dry season and then conversion
to rice during the wet, summer monsoon months. The increase in brick production has contributed to environmental problems
including decreased soil productivity, lowered ground water levels, and particularly air pollution. Brick manufacturing has
little, if any, effective regulation. There is a lack of current, accurate data on brick production that could be resolved
by remote sensing methods. Controls should be established and more information acquired on the location and impacts of brick
production. 相似文献
424.
When native grassland catchments are converted to pasture, the main effects on stream physicochemistry are usually related
to increased nutrient concentrations and fine-sediment input. We predicted that increasing nutrient concentrations would produce
a subsidy-stress response (where several ecological metrics first increase and then decrease at higher concentrations) and
that increasing sediment cover of the streambed would produce a linear decline in stream health. We predicted that the net
effect of agricultural development, estimated as percentage pastoral land cover, would have a nonlinear subsidy-stress or
threshold pattern. In our suite of 21 New Zealand streams, epilithic algal biomass and invertebrate density and biomass were
higher in catchments with a higher proportion of pastoral land cover, responding mainly to increased nutrient concentration.
Invertebrate species richness had a linear, negative relationship with fine-sediment cover but was unrelated to nutrients
or pastoral land cover. In accord with our predictions, several invertebrate stream health metrics (Ephemeroptera–Plecoptera–Trichoptera
density and richness, New Zealand Macroinvertebrate Community Index, and percent abundance of noninsect taxa) had nonlinear
relationships with pastoral land cover and nutrients. Most invertebrate health metrics usually had linear negative relationships
with fine-sediment cover. In this region, stream health, as indicated by macroinvertebrates, primarily followed a subsidy-stress
pattern with increasing pastoral development; management of these streams should focus on limiting development beyond the
point where negative effects are seen. 相似文献
425.
Nathan Frey 《Environmental Hazards》2018,17(1):40-55
Individuals’ relationships to place play an important role in their interactions with their residential environments. Prior research has suggested that neighbourhood satisfaction is closely related to neighbourhood attachment, and that attachment is linked to disaster recovery. This study uses data from a survey of residents of the East Shore neighbourhoods of Staten Island, New York, an area that experienced severe storm surge flooding during Hurricane Sandy, to test the association between neighbourhood satisfaction and self-reported recovery from the storm. Perceived recovery from Sandy is treated as the dependent variable in several ordinal logistic regression models. The key independent variable measure tested is neighbourhood satisfaction rating. A statistically significant direct positive relationship is found between neighbourhood satisfaction and perceived recovery from Sandy. This finding is robust across multiple models with various controls and other covariates. These results suggest that place satisfaction may contribute to disaster recovery. 相似文献
426.
Land Degradation: A Challenge to Ethiopia 总被引:11,自引:3,他引:8
Taddese G 《Environmental management》2001,27(6):815-824
Land degradation is a great threat for the future and it requires great effort and resources to ameliorate. The major causes
of land degradation in Ethiopia are the rapid population increase, severe soil loss, deforestation, low vegetative cover and
unbalanced crop and livestock production. Inappropriate land-use systems and land-tenure policies enhance desertification
and loss of agrobiodiversity. Utilization of dung and crop residues for fuel and other uses disturbs the sustainability of
land resources. The supply of inputs such as fertilizer, farm machinery and credits are very low. The balance between crop,
livestock, and forest production is disturbed, and the farmer is forced to put more land into crop production. For environmentally
and socially sustainable development, there is an urgent need to promote awareness and understanding of the interdependence
of natural, socioeconomic, and political systems at local and national levels. Understanding the current status and causes
of land degradation is very important. This paper reveals the important elements of land degradation in Ethiopia and suggests
possible solutions that may help to ameliorate the situation. 相似文献
427.
Gladden JN 《Environmental management》2001,27(3):367-376
The United States and Finland have passed laws to classify and manage Arctic wilderness areas, but their national policies
are based on different nature ideologies. Finns tend to perceive wilderness as a human-centered idea, while Americans are
inclined to see the same land from a nature-based point of view. Rural residents in the Arctic, and especially indigenous
peoples, use motorized vehicles for hunting and gathering in wilderness areas. Attempts of southern-based environmental groups
to restrict motor use by imposing a nature-based ideology on rural residents in northern Alaska will result in high levels
of political conflict. Alaska land managers need to respect the minority rights of rural residents and a study of wilderness
policies in Finnish Lapland is instructive toward this end. 相似文献
428.
Land Resource Sustainability for Urban Development: Spatial Decision Support System Prototype 总被引:1,自引:0,他引:1
Banai R 《Environmental management》2005,36(2):282-296
Land resource sustainability for urban development characterizes the problem of decision-making with multiplicity and uncertainty. A decision support system prototype aids in the assessment of incremental land development plan proposals put forth within the long-term community priority of a sustainable growth. Facilitating this assessment is the analytic hierarchy process (AHP), a multicriteria evaluation and decision support system. The decision support system incorporates multiple sustainability criteria, weighted strategically responsive to local public policy priorities and community–specific situations and values, while gauging and directing desirable future courses of development. Furthermore, the decision support system uses a GIS, which facilitates an assessment of urban form with multiple indicators of sustainability as spatial criteria thematically. The resultant land-use sustainability scores indicate, on the ratio-scale of AHP, whether or not a desirable urban form is likely in the long run, and if so, to what degree. The two alternative modes of synthesis in AHP—ideal and distributive—provide assessments of a land development plan incrementally (short-term) and city-wide pattern comprehensively (long-term), respectively. Thus, the spatial decision support system facilitates proactive and collective public policy determination of land resource for future sustainable urban development. 相似文献
429.
We present an integrated methodology for the optimal management of nitrate contamination of ground water combining environmental assessment and economic cost evaluation through multi-criteria decision analysis. The proposed methodology incorporates an integrated physical modeling framework accounting for on-ground nitrogen loading and losses, soil nitrogen dynamics, and fate and transport of nitrate in ground water to compute the sustainable on-ground nitrogen loading such that the maximum contaminant level is not violated. A number of protection alternatives to stipulate the predicted sustainable on-ground nitrogen loading are evaluated using the decision analysis that employs the importance order of criteria approach for ranking and selection of the protection alternatives. The methodology was successfully demonstrated for the Sumas-Blaine aquifer in Washington State. The results showed the importance of using this integrated approach which predicts the sustainable on-ground nitrogen loadings and provides an insight into the economic consequences generated in satisfying the environmental constraints. The results also show that the proposed decision analysis framework, within certain limitations, is effective when selecting alternatives with competing demands. 相似文献
430.
Effects of changing environments of riverside mangroves, coastal land uses, and water quality on fish communities were studied in Bangphra and Thaprik creeks, Trat Bay, Thailand. Regression analysis revealed that fish species richness in the wet season had a negative relationship with water transparency, nitrate, and phosphate and a positive relationship with zooplankton. In the dry season, species richness had a negative relationship with nitrate and phosphate and a positive relationship with salinity, pH, and zooplankton. Abundances and species richness of fish declined over distance from downstream to upstream in both creeks. Riparian mangroves and water quality also declined with distance upstream in both creeks. Results from one-way analysis of variance and Tukey’s HSD test revealed that the highest zooplankton volume with the lowest amounts of nitrate and phosphate were observed at the downstream station in both creeks in each season. Low zooplankton volume with high amounts of nitrate and phosphate were found at the midstream and upstream stations of the creeks. The midstream and upstream stations of Bangphra Creek had low to moderate abundance of mangroves along the riversides, whereas shrimp farms were mainly found along the riversides at the midstream and upstream stations of Thaprik Creek. Correlation analysis results of land-use types and the significant habitat factors were discussed. This study found that mangrove degradation, shrimp farming, and residential and agricultural areas altered water quality and the health of fish habitats, causing the decreases in fish abundance and species richness. 相似文献