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111.
Management effectiveness evaluation has been recognized as an important mechanism for both reporting on and improving protected area management. The Convention on Biological Diversity’s program of work on protected areas calls on all countries to implement such systems. In 2004, the first whole of system assessment of park management effectiveness, based on the IUCN-WCPA Management Effectiveness Evaluation Framework, was undertaken in New South Wales, Australia as part of a State of the Parks reporting requirement. This article describes the development of the State of the Parks assessment tool, its elements, and how it addresses the management effectiveness difficulties associated with assessments conducted across an extensive and diverse range of park types. The importance of engaging staff, at all levels, throughout the process is highlighted, as well as the adjustments made to the assessment tool based on staff feedback. While some results are presented, the main purpose of the article is to identify and discuss important procedural and methodological considerations. These include balancing quantitative and qualitative assessment approaches, achieving a comprehensive understanding of the management processes, and responding to any problems associated with assessments.  相似文献   
112.
Abstract

Commercially prepared ceralure‐B1, an attractant for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), was evaluated in trapping tests by comparison with commercial ceralure and trimedlure. Jackson traps were used for medfly captures. The residual ceralure‐B1, ceralure, and trimedlure contents of aged dispensers were determined. The results of this study show that male medfly captures from traps with ceralure‐B1 were as high or higher than male medfly captures from traps with twice the quantity of ceralure or trimedlure. The use of regioselectively synthesized ceralure‐B1, enriched in B1, as a source of a more potent attractant than commercial ceralure and as a more persistent male medfly attractant than trimedlure is reported.  相似文献   
113.
Abstract

For the first time, velocities were measured inside a fieldscale rotary kiln incinerator. Combustion gas velocities and temperatures were measured at multiple points across a quadrant of the kiln near its exit using a bidirectional pressure probe and suction pyrometer. To accommodate the new bidirectional probe and gain access to the upper portion of the kiln, a lighter and stiffer positioning boom was designed. The kiln was directly fired using natural gas in a steady state mode. Results indicate strong vertical stratification of both velocity and temperature, with the highest values corresponding to the top of the kiln. Access restraints prevented the lower region of the kiln from being mapped. Horizontal variations in both temperature and velocity were insignificant. Operating conditions were varied by adjusting the amount of ambient air added to the front of the kiln. Increasing the flow of ambient air into the front of the kiln reduced the measured temperatures as expected, but did hot have as significant an effect on measured velocities. The quality of the results is examined by performing mass balances across the incinerator and by comparison to an existing numerical model. Both methods indicate that the experimental results are reasonable.  相似文献   
114.
Both academics and practitioners consider a lack of knowledge about evolutionary theory to be a general barrier to effectively managing genetic diversity. However, it is challenging to judge practitioners’ level of understanding and how this influences their management decisions. Knowledge built through experience may be difficult for practitioners to articulate, but could nonetheless result in appropriate management strategies. To date, researchers have assessed only the explicit (formal) knowledge practitioners have of evolutionary concepts. To explore practitioners’ understanding of evolutionary concepts, it is necessary to consider how they might apply explicit and implicit knowledge to their management decisions. Using an online survey, we asked Australian practitioners to respond to 2 common management scenarios in which there is strong evidence that managing genetic diversity can improve outcomes: managing small, isolated populations and sourcing seeds for restoration projects. In describing their approach to these scenarios, practitioners demonstrated a stronger understanding of the effective management of genetic diversity than the definitions of the relevant concepts. However, their management of genetic diversity within small populations was closer to best practice than for restoration projects. Moreover, the risks practitioners described in implementing best practice management were more likely to affect their approach to restoration than translocation projects. These findings provide evidence that strategies to build the capacity of practitioners to manage genetic diversity should focus on realistic management scenarios. Given that practitioners recognize the importance of adapting their practices and the strong evidence for the benefits of actively managing genetic diversity, there is hope that better engagement by evolutionary biologists with practitioners could facilitate significant shifts toward evolutionarily enlightened management.  相似文献   
115.
116.
Texas water resources, already taxed by drought and population growth, could be further stressed by possible listings of endangered aquatic species. This study estimated potential economic impacts of environmental flows (EFs) for five freshwater unionid mussels in three Central Texas basins (Brazos, Colorado, and Guadalupe‐San Antonio Rivers) that encompass 36% of Texas (~246,000 km2). A water availability model projected reductions in water supply to power, commercial and industrial, municipal, and agriculture sectors in response to possible EFs for mussels. Single‐year economic impacts were calculated using publicly available data with and without water transfers. Benefits of EFs should also be assessed, should critical habitat be proposed. Potential economic losses were highest during droughts, but were nominal (<$1 M) in wetter years — even with high EFs. Reduced supplies to San Antonio area power plants caused worst‐case impacts of a single‐year shutdown up to $107 million (M) during drought with high EFs. For other sectors in the study area, water transfers reduced worst‐case losses from $80 to $11 M per year. Implementing innovative water management strategies such as water markets, conjunctive use of surface water and groundwater, aquifer storage and recovery could mitigate economic impacts if mussels — or other widely distributed aquatic species — were listed. However, approaches for defining EFs and strategies for mitigating economic impacts of EFs are needed.  相似文献   
117.
Seasonal changes in the free glycerol level in body parts of the adult barnacle Balanus balanoides have been followed during the 1969 season. Glycerol levels were highest in winter when the barnacles were most cold-tolerant and lowest in summer when they were least cold-tolerant. It is suggested that glycerol, and possibly other solutes, may be concentrated in the blood of B. balanoides, thus promoting supercooling and reducing the amount of ice formed at sub-zero temperatures.  相似文献   
118.
This paper describes a study of the geochemical associations of Sellafield waste radionuclides in saltmarsh sediments from south-west s]Scotland. The contaminant radionuclides are transported to this environment in association with particulate material and 137Cs was found to be predominantly (80-98%) non-extractable. In the case of 239+240Pu there was a redistribution from the oxalate extractable oxide fraction to the pyrophosphate extractable organic fraction as a consequence of on-shore transfer of contaminated sediment. The relatively aggressive nature of the chemical extractants required to remove the radionuclides from the sediments suggests that they were in a form which was unlikely to result in their being released into the aquatic environment or taken up by plants. Plutonium had a greater potential mobility or bioavailability than Cs. Values of KD for the desorption of 137Cs from the sediment by freshwater, groundwater and seawater were all approximately 105 L kg-1, confirming its immobility in this environment. The desorption KD values for stable 133Cs were all approximately 106 L kg-1, so the stable Cs did not have a significant influence on the radiocaesium in this sediment.  相似文献   
119.
The U.S. Environmental Protection Agency (US EPA) is placing increased emphasis on the selection and implementation of remedies that accommodate the reasonably anticipated future use of contaminated land. These remedies result in the long‐term protection of human health and the environment. Postconstruction reuse of the land can significantly benefit communities in other ways as well. The launching of the Superfund Redevelopment Initiative in 1999 and the Return to Use Initiative in 2004 reflects an evolution in the US EPA's understanding of what actions can be taken to support the reuse of Superfund sites from discovery through long‐term stewardship. Through these initiatives, the US EPA has increased its understanding of site reuse and continues to explore and implement reuse assessment, reuse planning, and other tools effective in integrating reuse considerations with response activities throughout the remedial process. © 2005 Wiley Periodicals, Inc.  相似文献   
120.
Cui H  Hwang HM  Cook S  Zeng K 《Chemosphere》2001,44(4):621-625
The effect of riboflavin (1 microM) on the fate of TNT (20 mg/l) in a natural water environment was studied. The relative contribution of photolysis, microbial assemblages and freshwater matrix to TNT degradation was examined. The rates, extent and products of TNT and riboflavin transformation were compared under different experimental conditions. It was found that riboflavin significantly enhanced the degradation of TNT in natural water environment. Thus it is a potentially useful photosensitizing agent for the treatment of TNT-contaminated surface water. Furthermore, in the presence of riboflavin, two new intermediates with max. absorption wavelength of 230 nm were found, demonstrating that transformation of TNT in the presence of riboflavin undergoes different pathways.  相似文献   
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