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Knowledge of the forces driving and modifying ecosystems can be employed in concert with signal analysis to target the data
most likely to yield sensitivity and resilience information. One can optimize return of information per investment of resources
by targeting segments of signals that are dominated by the force of interest, coupled with scientific understanding of the
system of interest. This force analysis approach is an effective means both to design efficient new monitoring programs and
to target relevant information in large data files. We present five example applications of force analysis. Three examples
illustrate this approach for an evaluation of whether Canadian rivers might be sensitive to changes in climate. It was concluded
that Canadian rivers appear to be sensitive to changing climate. A fourth example illustrates how automated snow pillow data
may be evaluated to ascertain the sensitivity of snow accumulation to change in climate. It was concluded that snow accumulation
at the site evaluated did appear to be sensitive to changing climate. The fifth example illustrates the assessment of whether
a river recovers with the elimination of inputs of iron from an abandoned mine. It was concluded that resilience remained
unproven since the river had not as yet restabilized. The force analysis approach focuses data collection or data evaluation
on those data required to answer specific resource management questions, greatly reducing collection or consideration of data
that are not relevant to that question. This approach is potentially very cost-efficient and therefore is likely to be of
interest to hydrologists, climatologists, and environmental data managers. 相似文献
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This paper summarizes the main physical and economic features of manganese nodules, cobalt-rich manganese crusts and marine polymetallic sulfide deposits in the Pacific region. The most favourable areas for deposits of commerical interest are shown on a map of the Pacific. The gross metal sales values of hypothetical mines are compared to estimated size of world metal markets in the year 2000. It is suggested that a prudent policy for the major developed-country governments is to support research on those marine minerals that appear to have the potential to become a major source of minerals in the next century. 相似文献
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The Complex Links between Governance and Biodiversity 总被引:1,自引:0,他引:1
CHRISTOPHER B. BARRETT CLARK C. GIBSON† BARAK HOFFMAN† MATHEW D. McCUBBINS † 《Conservation biology》2006,20(5):1358-1366
Abstract: We argue that two problems weaken the claims of those who link corruption and the exploitation of natural resources. The first is conceptual and the second is methodological. Studies that use national-level indicators of corruption fail to note that corruption comes in many forms, at multiple levels, that may affect resource use quite differently: negatively, positively, or not at all. Without a clear causal model of the mechanism by which corruption affects resources, one should treat with caution any estimated relationship between corruption and the state of natural resources. Simple, atheoretical models linking corruption measures and natural resource use typically do not account for other important control variables pivotal to the relationship between humans and natural resources. By way of illustration of these two general concerns, we used statistical methods to demonstrate that the findings of a recent, well-known study that posits a link between corruption and decreases in forests and elephants are not robust to simple conceptual and methodological refinements. In particular, once we controlled for a few plausible anthropogenic and biophysical conditioning factors, estimated the effects in changes rather than levels so as not to confound cross-sectional and longitudinal variation, and incorporated additional observations from the same data sources, corruption levels no longer had any explanatory power. 相似文献
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FLORA LU CLARK GRAY RICHARD E. BILSBORROW CARLOS F. MENA CHRISTINE M. ERLIEN JASON BREMNER ALISSON BARBIERI STEPHEN J. WALSH 《Conservation biology》2010,24(3):881-885
Abstract: To examine differences in land use and environmental impacts between colonist and indigenous populations in the northern Ecuadorian Amazon, we combined data from household surveys and remotely sensed imagery that was collected from 778 colonist households in 64 colonization sectors, and 499 households from five indigenous groups in 36 communities. Overall, measures of deforestation and forest fragmentation were significantly greater for colonists than indigenous peoples. On average, colonist households had approximately double the area in agriculture and cash crops and 5.5 times the area in pasture as indigenous households. Nevertheless, substantial variation in land‐use patterns existed among the five indigenous groups in measures such as cattle ownership and use of hired agricultural labor. These findings support the potential conservation value of indigenous lands while cautioning against uniform policies that homogenize indigenous ethnic groups. 相似文献
16.
Abstract: Conservation development projects combine real‐estate development with conservation of land and other natural resources. Thousands of such projects have been conducted in the United States and other countries through the involvement of private developers, landowners, land trusts, and government agencies. Previous research has demonstrated the potential value of conservation development for conserving species, ecological functions, and other resource values on private lands, especially when traditional sources of conservation funding are not available. Nevertheless, the aggregate extent and effects of conservation development were previously unknown. To address this gap, we estimated the extent and trends of conservation development in the United States and characterized its key attributes to understand its aggregate contribution to land‐conservation and growth‐management objectives. We interviewed representatives from land trusts, planning agencies, and development companies, searched the Internet for conservation development projects and programs, and compiled existing databases of conservation development projects. We collected data on 3884 projects encompassing 1.38 million ha. About 43% of the projects targeted the conservation of specific plant or animal species or ecological communities of conservation concern; 84% targeted the protection of native ecosystems representative of the project area; and 42% provided buffers to existing protected areas. The percentage of protected land in conservation development projects ranged from <40% to >99%, and the effects of these projects on natural resources differed widely. We estimate that conservation development projects have protected roughly 4 million ha of land in the United States and account for about 25% of private‐land conservation activity nationwide. 相似文献