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401.
Gordon Brent Ingram 《Environmental management》1992,16(5):585-595
Islands with large tracts of primary rain forest constitute a distinct complex of terrestrial and marine ecosystems with global
significance because of high levels of biological richness or, in the case of oceanic islands, the evolutionary distinctiveness
of the organisms that they support. The myriad of small habitat units makes these settings particularly prone to fragmentation
and thus problematic for the conservation of biological diversity. Most of the remaining examples of islands with primary
rain forest are in the Pacific Rim, particularly in Indonesia, and there are threats from intensive timber harvesting, mining,
tourism, and dismemberment of traditional convervation systems. Prospects for inventorying, monitoring, and protecting the
remaining islands with relatively pristine successional mosaics of humid forest and shallow marine habitats within a framework
global monitoring are explored. Recommendations are made for a program of expanded use of the biosphere reserve designation
for rain forest islands and adjacent marine areas. 相似文献
402.
Cooperation or conflict? Interagency relationships and the future of biodiversity for US parks and forests 总被引:1,自引:0,他引:1
R. Edward Grumbine 《Environmental management》1991,15(1):27-37
Cooperation between the United States Department of Agriculture (USDA) Forest Service and the United States Department of
Interior (USDI) National Park Service is most often advocated to protect biological diversity on national forests and parks,
but the agencies, so far, have done little to implement the biodiversity mandates of such laws as the Endangered Species Act
and the National Forest Management Act. The ideological and political history of the Forest Service and Park Service is explored
to determine the roots of interagency conflicts. Several recent models of cooperative reform are also critiqued and found
to be insufficient to stimulate better working relationships. To protect biodiversity, cooperation must be framed within conservation
biology and must place primary emphasis on ecosystem patterns and processes as well as on individual species. Increased education
of agency managers, ecosystem-level research, local and regional public participation, scientific oversight committees, new
legislation, and enlightened leadership also play important roles. Ultimately, management policies must be reframed within
a context of ecocentric values. 相似文献
403.
404.
Development and evaluation of a Macroinvertebrate Biotic Integrity Index (MBII) for regionally assessing Mid-Atlantic Highlands Streams 总被引:5,自引:0,他引:5
Klemm DJ Blocksom KA Fulk FA Herlihy AT Hughes RM Kaufmann PR Peck DV Stoddard JL Thoeny WT Griffith MB Davis WS 《Environmental management》2003,31(5):0656-0669
The Macroinvertebrate Biotic Integrity Index (MBII) was developed from data collected at 574 wadeable stream reaches in the
Mid-Atlantic Highlands region (MAHR) by the U.S. Environmental Protection Agency's (USEPA) Environmental Monitoring and Assessment
Program (EMAP). Over 100 candidate metrics were evaluated for range, precision, responsiveness to various disturbances, relationship
to catchment area, and redundancy. Seven metrics were selected, representing taxa richness (Ephemeroptera richness, Plecoptera
richness, Trichoptera richness), assemblage composition (percent non-insect individuals, percent 5 dominant taxa), pollution
tolerance [Macroinvertebrate Tolerance Index (MTI)], and one functional feeding group (collector-filterer richness). We scored
metrics and summed them, then ranked the resulting index through use of independently evaluated reference stream reaches.
Although sites were classified into lowland and upland ecoregional groups, we did not need to develop separate scoring criteria
for each ecoregional group. We were able to use the same metrics for pool and riffle composite samples, but we had to score
them differently. Using the EMAP probability design, we inferred the results, with known confidence bounds, to the 167,797
kilometers of wadeable streams in the Mid-Atlantic Highlands. We classified 17% of the target stream length in the MAHR as
good, 57% as fair, and 26% as poor. Pool-dominated reaches were relatively rare in the MAHR, and the usefulness of the MBII
was more difficult to assess in these reaches. The process used for developing the MBII is widely applicable and resulted
in an index effective in evaluating region-wide conditions and distinguishing good and impaired reaches among both upland
and lowland streams dominated by riffle habitat. 相似文献
405.
406.
A regional framework for establishing recovery criteria 总被引:6,自引:0,他引:6
Robert M. Hughes Thomas R. Whittier Christina M. Rohm David P. Larsen 《Environmental management》1990,14(5):673-683
Effective assessments of aquatic ecosystem recovery require ecologically sound endpoints against which progress can be measured.
Site-by-site assessments of end points and potential recovery trajectories are impractical for water resource agencies. Because
of the natural variation among ecosystems, applying a single set of criteria nationwide is not appropriate either. This article
demonstrates the use of a regional framework for stratifying natural variation and for determining realistic biological criteria.
A map of ecoregions, drawn from landscape characteristics, formed the framework for three statewide case studies and three
separate studies at the river basin scale. Statewide studies of Arkansas, Ohio, and Oregon, USA, streams demonstrated patterns
in fish assemblages corresponding to ecoregions. The river basin study in Oregon revealed a distinct change at the ecoregion
boundary; those in Ohio and Montana demonstrated the value of regional reference sites for assessing recovery. Ecoregions
can be used to facilitate the application of ecological theory and to set recovery criteria for various regions of states
or of the country. Such a framework provides an important alternative between site-specific and national approaches for assessing
recovery rates and conditions. 相似文献
407.
Budget changes, whether positive or negative, in water quality management agencies often mean a change in resources available for water quality monitoring. Many state agencies are currently facing monitoring budget cuts and, as a result, are reevaluating their monitoring programs. Such evaluations make use of a number of information sources, not the least of which are monitoring activities in other states. This article reports results of a survey of all fifty state water quality monitoring programs. Twenty questions were asked in the general areas of fixed-station monitoring, special studies, and biological monitoring. Each state was contacted by telephone at least twice during the survey. Fixed-station monitoring is conducted by 48 of 50 states. An average of 75 stations per state are sampled, generally on a monthly basis. There is a large variation in the way data are analyzed by the states; water quality indices and plots of concentration or loading over time are the most common methods. All but three states conduct special studies, but only seven repeat the studies on a regular basis. Special studies are generally problem specific as opposed to basin oriented. Biological monitoring is performed by 33 states; however, this is an area in which budget cuts are having a noticeable impact. In some cases, biological monitoring is being completely eliminated or suspended. Macroinvertebrate sampling is performed quarterly to biannualiy by 50% of the states; 75% of the states that sample macroinvertebrates do so annually. Periphyton sampling is performed by 33% of the states. Over 50% of the states are in the process of revising, or have revised, their monitoring program during the past five years. However, only four states had a detailed rationale and operating procedure for the entire monitoring system. Results of the survey are, therefore, averages of existing monitoring programs. Average results do not necessarily represent ideal situations, but do give an indication of how states are coping with their monitoring responsibilities. 相似文献
408.
文章概述了含砷废水的产生及其处理方法,重点介绍了国内外研究报道较少的活性污泥法,以引起人们对这一有效除砷方法的重视。通过总结活性污泥法除砷的研究进展,探讨了活性污泥除砷的机理和影响因素,并提出今后要从活性污泥法除砷的机理、除砷工艺、及含砷废渣处理三方面开展研究,以促进该方法的应用。 相似文献
409.
410.
添加EM菌对蚯蚓处理鲜牛粪的影响 总被引:1,自引:0,他引:1
蚯蚓处理鲜牛粪时,添加EM菌,通过堆制过程中pH、温度、速效养分含量、种子发芽率指数的变化以及添加EM菌对蚯蚓生长繁殖的影响,研究添加EM菌对蚯蚓处理鲜牛粪的影响。结果表明:加EM菌能显著提高蚯蚓的日增重倍数,对蚯蚓日繁殖倍数影响不大,以添加EM菌质量分数0.4%为宜。整个堆制过程加EM菌和未加EM菌的处理温度均未超过30℃,但在最初7d加EM菌处理的堆体温度略高于气温,在夏季利用蚯蚓处理鲜牛粪时,应注意翻堆散热,以利于蚯蚓生长。加EM菌能使鲜牛粪的初始pH从9.28降至8.76,利于蚯蚓适应环境。加EM菌能增加堆肥中速效氮、速效钾含量。加EM菌和未加EM菌的处理种子发芽指数均随堆制时间的增加而增大,堆制50d后种子发芽指数均达85%左右,且两者无显著差异,说明在蚯蚓处理鲜牛粪时,添加EM菌不能加速鲜牛粪的腐熟。 相似文献