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951.
Damon M. Hall Gerardo R. Camilo Rebecca K. Tonietto Jeff Ollerton Karin Ahrné Mike Arduser John S. Ascher Katherine C. R. Baldock Robert Fowler Gordon Frankie Dave Goulson Bengt Gunnarsson Mick E. Hanley Janet I. Jackson Gail Langellotto David Lowenstein Emily S. Minor Stacy M. Philpott Simon G. Potts Muzafar H. Sirohi Edward M. Spevak Graham N. Stone Caragh G. Threlfall 《Conservation biology》2017,31(1):24-29
Research on urban insect pollinators is changing views on the biological value and ecological importance of cities. The abundance and diversity of native bee species in urban landscapes that are absent in nearby rural lands evidence the biological value and ecological importance of cities and have implications for biodiversity conservation. Lagging behind this revised image of the city are urban conservation programs that historically have invested in education and outreach rather than programs designed to achieve high‐priority species conservation results. We synthesized research on urban bee species diversity and abundance to determine how urban conservation could be repositioned to better align with new views on the ecological importance of urban landscapes. Due to insect pollinators’ relatively small functional requirements—habitat range, life cycle, and nesting behavior—relative to larger mammals, we argue that pollinators put high‐priority and high‐impact urban conservation within reach. In a rapidly urbanizing world, transforming how environmental managers view the city can improve citizen engagement and contribute to the development of more sustainable urbanization. 相似文献
952.
Protected areas (PAs) and payments for ecosystem services (PES) are the top two mechanisms available for countries to achieve international REDD agreements, yet there are few empirical comparisons of their effects. We estimate the impacts of PAs and PES on forest conservation, poverty reduction, and population change at the locality level in Mexico in the 2000s. Both policies conserved forest, generating an approximately 20–25% reduction in expected forest cover loss. PES created statistically significant but small poverty alleviation while PAs had overall neutral impacts on livelihoods. Estimates by individual policy type for the same level of deforestation risk indicate that biosphere reserves and PES balanced conservation and livelihood goals better than strict protected areas or mixed-use areas. This suggests that both direct and incentive-based instruments can be effective, and that policies combining sustainable financing, flexible zoning, and recognition of local economic goals are more likely to achieve conservation without harming livelihoods. 相似文献
953.
Understanding human perspectives is critical in a range of conservation contexts, for example, in overcoming conflicts or developing projects that are acceptable to relevant stakeholders. The Q methodology is a unique semiquantitative technique used to explore human perspectives. It has been applied for decades in other disciplines and recently gained traction in conservation. This paper helps researchers assess when Q is useful for a given conservation question and what its use involves. To do so, we explained the steps necessary to conduct a Q study, from the research design to the interpretation of results. We provided recommendations to minimize biases in conducting a Q study, which can affect mostly when designing the study and collecting the data. We conducted a structured literature review of 52 studies to examine in what empirical conservation contexts Q has been used. Most studies were subnational or national cases, but some also address multinational or global questions. We found that Q has been applied to 4 broad types of conservation goals: addressing conflict, devising management alternatives, understanding policy acceptability, and critically reflecting on the values that implicitly influence research and practice. Through these applications, researchers found hidden views, understood opinions in depth and discovered points of consensus that facilitated unlocking difficult disagreements. The Q methodology has a clear procedure but is also flexible, allowing researchers explore long‐term views, or views about items other than statements, such as landscape images. We also found some inconsistencies in applying and, mainly, in reporting Q studies, whereby it was not possible to fully understand how the research was conducted or why some atypical research decisions had been taken in some studies. Accordingly, we suggest a reporting checklist. 相似文献
954.
Using empirical models of species colonization under multiple threatening processes to identify complementary threat‐mitigation strategies
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Ayesha I.T. Tulloch Alessio Mortelliti Geoffrey M. Kay Daniel Florance David Lindenmayer 《Conservation biology》2016,30(4):867-882
Approaches to prioritize conservation actions are gaining popularity. However, limited empirical evidence exists on which species might benefit most from threat mitigation and on what combination of threats, if mitigated simultaneously, would result in the best outcomes for biodiversity. We devised a way to prioritize threat mitigation at a regional scale with empirical evidence based on predicted changes to population dynamics—information that is lacking in most threat‐management prioritization frameworks that rely on expert elicitation. We used dynamic occupancy models to investigate the effects of multiple threats (tree cover, grazing, and presence of an hyperaggressive competitor, the Noisy Miner (Manorina melanocephala) on bird‐population dynamics in an endangered woodland community in southeastern Australia. The 3 threatening processes had different effects on different species. We used predicted patch‐colonization probabilities to estimate the benefit to each species of removing one or more threats. We then determined the complementary set of threat‐mitigation strategies that maximized colonization of all species while ensuring that redundant actions with little benefit were avoided. The single action that resulted in the highest colonization was increasing tree cover, which increased patch colonization by 5% and 11% on average across all species and for declining species, respectively. Combining Noisy Miner control with increasing tree cover increased species colonization by 10% and 19% on average for all species and for declining species respectively, and was a higher priority than changing grazing regimes. Guidance for prioritizing threat mitigation is critical in the face of cumulative threatening processes. By incorporating population dynamics in prioritization of threat management, our approach helps ensure funding is not wasted on ineffective management programs that target the wrong threats or species. 相似文献
955.
针对目前我国非煤矿山在安全制度管理过程中常常出现刚性有余而柔性不足的缺陷,总结出非煤矿山在制订、执行和完善安全制度中存在的问题主要表现在安全制度的制订与实际符合度不高、安全制度的执行过程重形式轻实践、对安全制度的完善重视度不够3个方面。引入道家"自然无为"思想,分析了"自然无为"思想对安全制度的制订、执行和完善3个阶段的影响。提出在安全制度的制订时注重"道法自然";在安全制度的执行时强调"三和"观;在安全制度的完善时注重"顺道而为"。将道家"自然无为"思想与安全制度管理相融合,能有效增强安全制度管理的"人情味",使其更好地发挥基础保障作用。 相似文献
956.
957.
For a sustainable municipal sewage sludge management, not only the available technology, but also other parameters, such as policy regulations and socio-economic issues should be taken in account. In this study, the current status of both European and Greek Legislation on waste management, with a special insight in municipal sewage sludge, is presented. A SWOT analysis was further developed for comparison of pyrolysis with incineration and gasification and results are presented. Pyrolysis seems to be the optimal thermochemical treatment option compared to incineration and gasification. Sewage sludge pyrolysis is favorable for energy savings, material recovery and high added materials production, providing a ‘zero waste’ solution. Finally, identification of challenges and barriers for sewage sludge pyrolysis deployment in Greece was investigated. 相似文献
958.
Mitigating the massive impacts of defaunation on natural ecosystems requires understanding and predicting hunting effort across the landscape. But such understanding has been hindered by the difficulty of assessing the movement patterns of hunters in thick forests and across complex terrain. We statistically tested hypotheses about the spatial distribution of hunting with circuit theory and structural equation models. We used a data set of >7000 known kill locations in Guyana and hunter movement models to test these methods. Comparing models with different resistance layers (i.e., different estimates of how terrain and land cover influence human movement speed) showed that rivers, on average, limited movement rather than serving as transport arteries. Moreover, far more kills occurred close to villages than in remote areas. This, combined with the lack of support for structural equation models that included latent terms for prey depletion driven by past overhunting, suggests that kill locations in this system tended to be driven by where hunters were currently foraging rather than by influences of historical harvest. These analyses are generalizable to a variety of ecosystems, species, and data types, providing a powerful way of enhancing maps and predictions of hunting effort across complex landscapes. 相似文献
959.
Scientific insights into what it means to manage on-farm trees by local farmers, is an essential step towards documenting local ecological knowledge for sustainable landscape management. A study was therefore conducted in the Kumawu Forest District in the Ashanti Region of Ghana to assess how farmers conceptualise on-farm tree management and develop local knowledge for it. Using a case study approach, data were collected through informal interviews and focus group discussions with 120 farmers drawn from 15 communities who were involved in the management of three cropping systems; cocoa, maize and cassava-cocoyam-plantain mix. It was observed that the farmers regard on-farm tree management as a continuous process which occurs in three phases of the farming cycle; land preparation, crop cultivation and fallow management. For each of the three phases, farmers are guided by specific principles that ensure enough light penetration in-between tree crowns in the land preparation phase, suitable spacing between trees and crops in the crop cultivation phase and adequate tree regeneration in the fallow phase. The decisions made during the selection of tree species, spacing of trees adjudged suitable for any particular cropping system and recruitment of saplings prior to the fallow phase of farming constitute tree management. Farmers develop tree management knowledge by studying the physical characteristics of species, matching them to ecological functions they could perform and how they are likely to respond to treatments meant to control or enhance their development. Species are then subjected to trial and recommended or otherwise. 相似文献
960.
Cara E. Brook James P. Herrera Cortni Borgerson Emma C. Fuller Pascal Andriamahazoarivosoa B. J. Rodolph Rasolofoniaina J. L. Rado Ravoavy Randrianasolo Z. R. Eli Rakotondrafarasata Hervet J. Randriamady Andrew P. Dobson Christopher D. Golden 《Conservation biology》2019,33(1):99-111
Subsistence hunting presents a conservation challenge by which biodiversity preservation must be balanced with safeguarding of human livelihoods. Globally, subsistence hunting threatens primate populations, including Madagascar's endemic lemurs. We used population viability analysis to assess the sustainability of lemur hunting in Makira Natural Park, Madagascar. We identified trends in seasonal hunting of 11 Makira lemur species from household interview data, estimated local lemur densities in populations adjacent to focal villages via transect surveys, and quantified extinction vulnerability for these populations based on species-specific demographic parameters and empirically derived hunting rates. We compared stage-based Lefkovitch with periodic Leslie matrices to evaluate the impact of regional dispersal on persistence trajectories and explored the consequences of perturbations to the timing of peak hunting relative to the lemur birth pulse, under assumptions of density-dependent reproductive compensation. Lemur hunting peaked during the fruit-abundant wet season (March–June). Estimated local lemur densities were roughly inverse to body size across our study area. Life-history modeling indicated that hunting most severely threatened the species with the largest bodies (i.e., Hapalemur occidentalis, Avahi laniger, Daubentonia madagascariensis, and Indri indi), characterized by late-age reproductive onsets and long interbirth intervals. In model simulations, lemur dispersal within a regional metapopulation buffered extinction threats when a majority of local sites supported growth rates above the replacement level but drove regional extirpations when most local sites were overharvested. Hunt simulations were most detrimental when timed to overlap lemur births (a reality for D. madagascariensis and I. indri). In sum, Makira lemurs were overharvested. Regional extirpations, which may contribute to broad-scale extinctions, will be likely if current hunting rates persist. Cessation of anthropogenic lemur harvest is a conservation priority, and development programs are needed to help communities switch from wildlife consumption to domestic protein alternatives. 相似文献