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651.
Stephanie J. Perles Tyler Wagner Brian J. Irwin Douglas R. Manning Kristina K. Callahan Matthew R. Marshall 《Environmental management》2014,54(3):641-655
Forests are socioeconomically and ecologically important ecosystems that are exposed to a variety of natural and anthropogenic stressors. As such, monitoring forest condition and detecting temporal changes therein remain critical to sound public and private forestland management. The National Parks Service’s Vital Signs monitoring program collects information on many forest health indicators, including species richness, cover by exotics, browse pressure, and forest regeneration. We applied a mixed-model approach to partition variability in data for 30 forest health indicators collected from several national parks in the eastern United States. We then used the estimated variance components in a simulation model to evaluate trend detection capabilities for each indicator. We investigated the extent to which the following factors affected ability to detect trends: (a) sample design: using simple panel versus connected panel design, (b) effect size: increasing trend magnitude, (c) sample size: varying the number of plots sampled each year, and (d) stratified sampling: post-stratifying plots into vegetation domains. Statistical power varied among indicators; however, indicators that measured the proportion of a total yielded higher power when compared to indicators that measured absolute or average values. In addition, the total variability for an indicator appeared to influence power to detect temporal trends more than how total variance was partitioned among spatial and temporal sources. Based on these analyses and the monitoring objectives of the Vital Signs program, the current sampling design is likely overly intensive for detecting a 5 % trend·year?1 for all indicators and is appropriate for detecting a 1 % trend·year?1 in most indicators. 相似文献
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Online crowdfunding can help address the perennial financial shortfalls in environmental conservation and management. Although many online crowdfunding campaigns fail to collect any funds due to not achieving their targets, little is known about what drives success. To address this knowledge gap, we applied a mixed-methods approach to data from 473 successful and failed campaigns hosted on the online crowdfunding platform Readyfor. We found that fundraising performance varied by topic, with campaigns on pet animal management outperforming those focussed on landscape management and sustainable use. We also found that marketing strategies associated with online findability and increased reach through social networks, increased fundraising success. However, the existence of other environmental campaigns running simultaneously, reduced the chance of success, which implies that the selecting popular topics does not always increase the likelihood of success due to increased competition. Wider applications of marketing could enhance the ability of environmental crowdfunding campaigns to raise funds.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01522-0. 相似文献
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Zachary Douglas Cole Holly M. Donohoe Michael L. Stellefson 《Environmental management》2013,51(3):511-523
The interactive capacity of the Internet offers benefits that are intimately linked with contemporary research innovation in the natural resource and environmental studies domains. However, e-research methodologies, such as the e-Delphi technique, have yet to undergo critical review. This study advances methodological discourse on the e-Delphi technique by critically assessing an e-Delphi case study. The analysis suggests that the benefits of using e-Delphi are noteworthy but the authors acknowledge that researchers are likely to face challenges that could potentially compromise research validity and reliability. To ensure that these issues are sufficiently considered when planning and designing an e-Delphi, important facets of the technique are discussed and recommendations are offered to help the environmental researcher avoid potential pitfalls associated with coordinating e-Delphi research. 相似文献
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Adam B. Munson Joseph J. Delfino Douglas A. Leeper 《Journal of the American Water Resources Association》2005,41(1):1-10
ABSTRACT: Florida water resources are among the most abundant in the United States, with Florida receiving the second‐highest mean annual rainfall of all states. However, water supply issues have troubled the state due to the highly variable spatial and temporal distributions of water supply and demand, and they are aggravated by the population's preference for settling in coastal regions where freshwater resources are scarce. Historically, the competing issues of water resource development and natural systems protection have placed water management agencies and local governments at odds. In 1997, the Florida Legislature enacted several major changes to Florida water law in an attempt to improve water resource planning and protection. This paper briefly reviews the history of water management in Florida with an emphasis on decisions culminating in the 1997 legislation, which requires the development of minimum flows and levels. Also examined is the impact of the 1997 law on water management. Efforts made to comply with legislative mandates are summarized; these include, to date, establishment of minimum flows and levels on 209 water bodies and budgeting in excess of $1.4 billion for water resource development projects. 相似文献
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