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11.
For effective monitoring in social–ecological systems to meet needs for biodiversity, science, and humans, desired outcomes must be clearly defined and routes from direct to derived outcomes understood. The Arctic is undergoing rapid climatic, ecological, social, and economic changes and requires effective wildlife monitoring to meet diverse stakeholder needs. To identify stakeholder priorities concerning desired outcomes of arctic wildlife monitoring, we conducted in-depth interviews with 29 arctic scientists, policy and decision makers, and representatives of indigenous organizations and nongovernmental organizations. Using qualitative content analysis, we identified and defined desired outcomes and documented links between outcomes. Using network analysis, we investigated the structure of perceived links between desired outcomes. We identified 18 desired outcomes from monitoring and classified them as either driven by monitoring information, monitoring process, or a combination of both. Highly cited outcomes were make decisions, conserve, detect change, disseminate, and secure food. These reflect key foci of arctic monitoring. Infrequently cited outcomes (e.g., govern) were emerging themes. Three modules comprised our outcome network. The modularity highlighted the low strength of perceived links between outcomes that were primarily information driven or more derived (e.g., detect change, make decisions, conserve, or secure food) and outcomes that were primarily process driven or more derived (e.g., cooperate, learn, educate). The outcomes expand monitoring community and disseminate created connections between these modules. Key desired outcomes are widely applicable to social–ecological systems within and outside the Arctic, particularly those with wildlife subsistence economies. Attributes and motivations associated with outcomes can guide development of integrated monitoring goals for biodiversity conservation and human needs. Our results demonstrated the disconnect between information- and process-driven goals and how expansion of the monitoring community and improved integration of monitoring stakeholders will help connect information- and process-derived outcomes for effective ecosystem stewardship.  相似文献   
12.
The anticipated labor shortages of the 1990's will intensify organizational needs to retain their existing employees. Women represent an increasingly important segment of the labor force and their turnover rates are thought to exceed men's. Earlier studies of turnover and its psychological antecedent, the behavioral intention to leave, suggest that work-related factors may contribute to women's relatively higher turnover rates. The current paper reports the results of a study of the intentions of male and female executives, managers and professionals to leave their organizations. The results support the pattern of findings in earlier studies that gender differences disappear when job satisfaction is controlled in the analysis. Further analysis highlights the importance of two components of job satisfaction — meaningful work and opportunities for promotion. The authors conclude that organizations might improve their retention rates of female managers through job enrichment and by enhancing their advancement opportunities.  相似文献   
13.
The uptake of inorganic carbon into the thallus of Macrocystis pyrifera (L.) C. Ag. requires first that the inorganic carbon pass through the water medium to the plant surface. This transfer of inorganic carbon to the thallus must take place through a boundary layer. Experiments in water tunnels indicate that the boundary layer adjacent to the M. pyrifera blade may be turbulent in water speeds as low as 1 cm sec-1. Photosynthetic output of the blade can be increased by a factor of 300% by increasing water speeds over the blade surface from 0 to 4 cm sec-1. This is consistent with a decrease in the thickness of the boundary layer. Above 4 cm sec-1, the assimilation of carbon was limiting. The assimilation of carbon is generally known to follow Michaelis-Menten-like kinetics. Combining the two uptake steps into an overall model of carbon uptake agrees well with photosynthetic data obtained from M. pyrifera under varying conditions of water speed and bicarbonate concentrations in the laboratory. The ecological and morphological consequences of these findings are discussed.  相似文献   
14.
毫不令人吃惊,通过保护濒危物种,诸如老虎、犀牛和大熊猫,全世界大多数人都与世界野生动物基金会(WWF)和著名的大熊猫标志有联系.然而,为什么WWF会对人类在地球上的住宅感兴趣呢?……  相似文献   
15.
Correlations between structural properties of bivalve shell organic matrix and its proposed functions in the regulation of biomineralization were examined using proteinaceous fractions obtained from the shell of the oyster Crassostrea virginica (Gmelin) following dissolution of the mineral with ethylenediaminetetraacetate (EDTA). Matrix isolated in this way contains a continuous size distribution of proteins ranging from relatively small molecular weight (Mr) soluble matrix (SM) components to insoluble matrix (IM) components. Regulation of mineralization by these components was determined primarily by their reduction of crystal growth rate in an in vitro assay. For all fractions tested, there was an inverse correlation between Mr and regulatory activity. However, matrix properties other than molecular size may be important in regulation of crystal growth in vivo in that the larger but less acidic of two soluble matrix proteins was a more effective inhibitor of spicule formation by sea urchin embryos. Base treatment of IM and high molecular weight SM fractions that had little or no inhibitory activity when untreated, resulted in constituents that had a molecular weight distribution and in vitro inhibitory activity in the same range as whole SM. These results, combined with the finding that a major fraction of IM has an amino acid composition very similar to the highly charged SM fractions, suggest that much of the matrix is made up of similar molecules, and that their function in crystal growth regulation may change as they interact to form units of increasing size. A second class of IM was isolated which contained dihydroxyphenylalanine (dopa) and a preponderance of hydrophobic amino acids. This material may represent the basic structural framework of the matrix.  相似文献   
16.
Regional Environmental Change - Increasing pressure on shared water resources has often been a driver for the development and utilisation of water resource models (WRMs) to inform planning and...  相似文献   
17.
Data analysis and modeling were performed to characterize the spatial and temporal variability of wintertime transport and dispersion processes and the impact of these processes on particulate matter (PM) concentrations in the California San Joaquin Valley (SJV). Radar wind profiler (RWP) and radio acoustic sounding system (RASS) data collected from 18 sites throughout Central California were used to estimate hourly mixing heights for a 3-month period and to create case studies of high-resolution diagnostic wind fields, which were used for trajectory and dispersion analyses. Data analyses show that PM episodes were characterized by an upper-level ridge of high pressure that generally produced light winds through the entire depth of the atmospheric boundary layer and low mixing heights compared with nonepisode days. Peak daytime mixing heights during episodes were -400 m above ground level (agl) compared with -800 m agl during nonepisodes. These episode/nonepisode differences were observed throughout the SJV. Dispersion modeling indicates that the range of influence of primary PM emitted in major population centers within the SJV ranged from -15 to 50 km. Trajectory analyses revealed that little intrabasin pollutant transport occurred among major population centers in the SJV; however, interbasin transport from the northern SJV and Sacramento regions into the San Francisco Bay Area (SFBA) was often observed. In addition, this analysis demonstrates the usefulness of integrating RWP/RASS measurements into data analyses and modeling to improve the understanding of meteorological processes that impact pollution, such as aloft transport and boundary layer evolution.  相似文献   
18.
19.
In this paper we describe a new incentive-based pollution control program in China, in which the environmental performance of firms is rated from best to worst using five colors--green, blue, yellow, red and black--and the ratings are disseminated to the public through the media. We focus on the first two municipal disclosure programs, which have been implemented at very different levels of economic and institutional development. In both cases, the increases in compliance with pollution regulations have been similar to increases produced by public disclosure programs in Indonesia, the Philippines, and Vietnam. The results suggest that incentives created by public disclosure may significantly reduce pollution in China, even though environmental NGO's play little role and there is no formal channel for public participation in environmental regulation.  相似文献   
20.
Book reviews     
ANALYTICAL PLANNING: THE ORGANISATION OF SYSTEMS

Thomas L. Saaty and Kevin P. Kearns

Pergamon Press, 1985. Price: U.S. $40.00, U.K. £29.50.

THE GEOGRAPHER AT WORK

Peter Gould

Routledge and Kegan Paul, London 1985’ Price: £8.95.

UTOPIA ON TRIAL

Alice Colman

Hilary Shipman Ltd., 19 Framfield Road, Highbury, London. May 1985 (reprinted August, 1985). Price: £7.95.

SIR RAYMOND UNWIN: ARCHITECT, PLANNER AND VISIONARY

Frank Jackson

A. Zwemmer Ltd., London 1985. 187 pp. with maps and illustrations.

STRATEGIC PLANNING IN ACTION: THE IMPACT OF THE CLYDE VALLEY REGIONAL PLAN 1946–1982

R. Smith and U. Wannop (eds)

Gower, 1985, 272 pp. Price: £16.50.

LOCALITIES, CLASS AND GENDER

The Lancaster Regionalism Group (Linda Murgatroyd, Mike Savage, Dan Shapiro, John Urry, Sylvia Walby, Alan Warde, with Jane Mark‐Lawson)

Pion Ltd., 1985. Price: £12.00.  相似文献   

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