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211.
Wetland Mitigation Compliance in the Western Upper Peninsula of Michigan   总被引:3,自引:3,他引:0  
The Army Corps of Engineers (ACE) is generally responsible for the implementation of federal Clean Water Act wetland regulations. It therefore plays an important role in the protection of wetlands within the United States. Unfortunately, past evaluators of ACEs implementation of these regulations found low rates of regulatory compliance. However, the fact that two states have taken responsibility for the implementation of these regulations within their boundaries provided the opportunity to assess whether one of these states might be doing a better job of enforcement. This paper reports on compliance with some of these regulations within one Michigan region. We evaluated permittee compliance with paperwork filing requirements related to wetland mitigation projects. Sixty-seven percent of county road commission permittees were out of compliance with at least one filing requirement. Forty percent of private and non-county government permittees were out of compliance. Our results therefore suggest that serious problems exist with Michigans implementation of wetland regulations. They do not suggest that compliance in this state is significantly better than in states under ACE administration. We believe that increased agency monitoring and enforcement would improve compliance.  相似文献   
212.
Protected area management involves balancing environmental and social objectives. This is particularly difficult at high-use/high-impact recreation sites, because resource protection objectives may require substantial site management or visitor regulation. This study examined visitors’ reactions to both of these types of actions at Annapolis Rocks, Maryland, a popular Appalachian Trail camping area. We surveyed visitors before and after implementation of camping policies that included shifting camping to designated newly constructed campsites and prohibiting campfires. Survey results reveal that visitors were more satisfied with all social and environmental indicators after the changes were enacted. An Importance-Performance analysis also determined that management actions improved conditions for factors of greatest concern to campers prior to the changes. Posttreatment visitors were least satisfied with factors related to reduced freedom and to some characteristics of the constructed campsites. Although there was evidence of visitor displacement, the camping changes met management goals by protecting the camping area’s natural resources and improving social conditions.  相似文献   
213.

The rise in global temperature is one of the main threats of extinction to many vulnerable species by the twenty-first century. The negative impacts of climate change on the northern highlands of Pakistan (NHP) could change the species composition. Range shifts and range reduction in the forested landscapes will dramatically affect the distribution of forest-dwelling species, including the Galliformes (ground birds). Three Galliformes (e.g., Lophophorus impejanus, Pucrasia macrolopha, and Tragopan melanocephalus) are indicator species of the environment and currently distributed in NHP. For this study, we used Maximum Entropy Model (MaxEnt) to simulate the current (average for 1960–1990) and future (in 2050 and 2070) distributions of the species using three General Circulation Models (GCMs) and two climate change scenarios, i.e., RCP4.5 (moderate carbon emission scenario) and RCP8.5 (peak carbon emission scenario). Our results indicated that (i) under all three climate scenarios, species distribution was predicted to both reduce and shift towards higher altitudes. (ii) Across the provinces in the NHP, the species were predicted to average lose around one-third (35%) in 2050 and one-half (47%) by 2070 of the current suitable habitat. (iii) The maximum area of climate refugia was projected between the altitudinal range of 2000 to 4000 m and predicted to shift towards higher altitudes primarily?>?3000 m in the future. Our results help inform management plans and conservation strategies for mitigating the impacts of climate change on three indicator Galliforms species in the NHP.

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214.
Environmental Chemistry Letters - The rise of emerging contaminants in waters challenges the scientific community and water treatment stakeholders to design remediation techniques that are simple,...  相似文献   
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