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81.
Hans Tφmmervik 《Ambio-人类环境杂志》2003,32(8):553-562
在解决复杂的土地管理问题时,对短缺或者有争执的资源进行地理评估有助于不同利益相关者之间沟通认识和增进理解.本文中,我们说明如何使用遥感和GIS收集和汇总瑞典北部驯鹿放牧者和其他土地使用者(林业、采矿业、旅游业等等)的土地使用活动及使用模式的信息.该项目主要基于最终的土地使用者,即驯鹿放牧者们所做的工作,体现了面向土地使用者的新的努力.发展驯鹿业的土地利用规划的基础有以下几个方面:收集并数字化传统的驯鹿栖息地生态学和景观信息将这些信息与来自野外调查及基于人造卫星观测的植被分类结果整合;绘制其他土地使用者的活动情况图.最终的土地利用规划提供的信息有利于驯鹿放牧者与其他利益相关者之间的磋商,并有助于驯鹿管理实施.该项目可作为一种大众参与和计划编制的模式,从而使本土信息和先进的遥感技术融入一个交互式的过程中. 相似文献
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Critical swimming speeds of late-stage coral reef fish larvae: variation within species,among species and between locations 总被引:3,自引:0,他引:3
Rebecca?FisherEmail author Jeffrey?M.?Leis Domine?L.?Clark Shaun?K.?Wilson 《Marine Biology》2005,147(5):1201-1212
The swimming abilities of larval fishes are important for their survival, potentially affecting their ability to avoid predators,
obtain food and control dispersal patterns. Near settlement swimming abilities may also influence spatial and temporal patterns
of recruitment. We examined Critical speed (U-crit) swimming ability in late stage larvae of 89 species of coral reef fishes from the Great Barrier Reef and the Caribbean.
Coefficients of variation in U-crit calculated at the individual level were high (28.4%), and this was not explained by differences in size or condition
factor of these same larvae. Among species U-crit ranged from 5.5 cm s−1 to 100.8 cm s−1 (mean=37.3 cm s−1), with 95% of species able to swim faster than the average current speed around Lizard Island, suggesting that most species
should be capable of influencing their spatial and temporal patterns of settlement. Inter-specific differences in swimming
ability (at both the family and species levels) were significantly correlated with size and larval morphology. Correlations
were found between swimming performance and propulsive area, fineness ratio and aspect ratio, and these morphological parameters
may prove useful for predicting swimming ability in other taxa. Overall, the swimming speeds of larvae from the same families
at the two locations were relatively similar, although the Lutjanidae and Acanthuridae from the Caribbean were significantly
slower than those from the great barrier reef. Differences in swimming speed and body form among late stage larvae suggests
that they will respond differently to factors influencing survival and transport during their pelagic phase, as well as habitat
use following settlement. 相似文献
84.
Potential effects of forest policies on terrestrial biodiversity in a multi-ownership province. 总被引:1,自引:0,他引:1
Thomas A Spies Brenda C McComb Rebecca S H Kennedy Michael T McGrath Keith Olsen Robert J Pabst 《Ecological applications》2007,17(1):48-65
We used spatial simulation models to evaluate how current and two alternative policies might affect potential biodiversity over 100 years in the Coast Ranges Physiographic Province of Oregon. This 2.3-million-ha province is characterized by a diversity of public and private forest owners, and a wide range of forest policy and management objectives. We evaluated habitat availability for seven focal species representing different life histories. We also examined how policies affected old-growth stand structure, age distributions relative to the historical range of variability, and landscape patterns of forest types. Under the current policy scenario, the area of habitat for old-growth forest structure and associated species increased over time, the habitat for some early-successional associates remained stable, and the area of hardwood vegetation and diverse early-successional stages declined. The province is projected to move toward but not reach the historical range of variation of forest age classes that may have occurred under the wildfire regimes of the pre-Euroamerican settlement period. Ownership explained much of the pattern of biodiversity in the province, and under the current policy scenario, its effect increased over time as the landscape diverged into highly contrasting forest structures and ages. Patch type diversity declined slightly overall but declined strongly within ownerships. Most of the modeled change in biodiversity over time resulted from policies on public forest lands that were intended to increase the area of late-successional forests and species. One of the alternative policies, increased retention of wildlife trees on private lands, reduced the contrast between ownerships and increased habitat availability over time for both early- and late-successional species. Analysis of another alternative, stopping thinning of plantations on federal lands, indicated that current thinning regimes improve habitat for the Olive-sided Flycatcher, but the no-thinning alternative had no effect on the habitat scores for the late-successional species in the 100-year simulation. A comparison of indicators of biological diversity suggests that using focal species and forest structural measures can provide complementary information on biodiversity. The multi-ownership perspective provided a more complete synthesis of province-wide biodiversity patterns than assessments based on single ownerships. 相似文献
85.
Rebecca Efroymson Henriette Jager Virginia Dale James Westervelt 《Environmental management》2009,44(6):1163-1179
A decision framework for setting management goals for species at risk is presented. Species at risk are those whose potential
future rarity is of concern. Listing these species as threatened or endangered could potentially result in significant restrictions
to activities in resource management areas in order to maintain those species. The decision framework, designed to foster
proactive management, has nine steps: identify species at risk on and near the management area, describe available information
and potential information gaps for each species, determine the potential distribution of species and their habitat, select
metrics for describing species status, assess the status of local population or metapopulation, conduct threat assessment,
set and prioritize management goals, develop species management plans, and develop criteria for ending special species management
where possible. This framework will aid resource managers in setting management goals that minimally impact human activities
while reducing the likelihood that species at risk will become rare in the near future. The management areas in many of the
examples are United States (US) military installations, which are concerned about potential restrictions to military training
capacity if species at risk become regulated under the US Endangered Species Act. The benefits of the proactive management
set forth in this formal decision framework are that it is impartial, provides a clear procedure, calls for identification
of causal relationships that may not be obvious, provides a way to target the most urgent needs, reduces costs, enhances public
confidence, and, most importantly, decreases the chance of species becoming more rare. 相似文献
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Rebecca M. Willson Zeev Wiesman Asher Brenner 《Waste management (New York, N.Y.)》2010,30(10):1881-1888
Production of biodiesel is currently limited due to lack of economically beneficial feedstocks. Suitability of municipal wastewater sludge and olive mill waste as feedstocks for biodiesel production was evaluated. The various bio-waste sources were analyzed for their oil content and fatty acid composition using conventional analyses complemented with time domain (TD)-NMR analysis. TD-NMR, a rapid non-destructive method newly applied in this field, yielded good correlations with conventional methods. Overall biodiesel yields obtained by TD-NMR analysis were 7.05% and 9.18% (dry wt) for olive mill pomace and liquid wastes, and 11.92%, 7.07%, and 4.65% (dry wt) for primary, secondary, and anaerobically stabilized sludge, respectively. Fatty acid analysis indicated fundamental suitability of these agro-industrial waste resources for biodiesel production. Evaluation of bio-waste materials by TD-NMR revealed the potential of this tool to identify waste-oil sources cost effectively and quickly, supporting expansion of a sustainable biodiesel industry in Israel and other regions. 相似文献
90.
David R. Breininger Mary Jo Barkaszi Rebecca B. Smith Donna M. Oddy Jane A. Provancha 《Environmental management》1998,22(2):315-321
/ We identified and ranked 108 resident and migratory wildlife taxa on John F. Kennedy Space Center (KSC) that were vulnerable to local, regional, or global extinction. We ranked taxa based on their vulnerability to extinction, their potential role for maintaining faunal integrity, and the relevance of KSC for maintaining their populations in the United States and Florida. Several taxa, not listed by agencies, were vulnerable to regional or global extinction. Many taxa not vulnerable to global extinction were vulnerable to local and regional extinction. Top predators were vulnerable to extinction because of small population size, isolation from other populations, and road mortality. Many taxa were dependent on habitat conditions at different geographic locations so that conservation required greater collaboration among land owners, managers, and researchers at local, regional, and global scales.KEY WORDS: Biological diversity; Endangered species; Conservation 相似文献