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381.
The extraordinary population growth of certain ungulate species is increasingly a concern in agroforestry areas because overabundance may negatively affect natural environments and human livelihoods. However, society may have negative perceptions of killing wildlife to reduce their numbers and mitigate damage. We used an online survey that included a choice experiment to determine Spanish citizens’ (n = 190) preferences toward wildlife population control measures related to negative effects of ungulate overabundance (negative impacts on vegetation and other wildlife species and disease transmission to livestock) in 2 agroforestry national parks in Spain. We used latent-class and willingness-to-pay in space models to analyze survey results. Two percent of respondents thought a national park should have no human intervention even if lack of management may cause environmental degradation, whereas 95% of respondents favored efforts to reduce damage caused by overabundant ungulate species. We estimated human well-being losses of survey respondents when sustainable effects of deer overabundance on the environment became unsustainable effects and well-being gains when sustainable effects transitioned to no visible effects. We found that the type of wildlife-control program was a very relevant issue for the respondents; indirect control in which killing was avoided was the preferred action. Sixty-six percent of respondents agreed with the option of hunters paying for culling animals to reduce ungulate impacts rather than management cost coming out of taxes, whereas 19% of respondents were against this option and willing to pay for other solutions in national parks. Our results suggest that killing wildlife in national parks could be a socially acceptable tool to manage overabundance problems in certain contexts, but it could also generate social conflicts.  相似文献   
382.
Protected areas (PAs) are a frequently used conservation strategy, yet their socioeconomic impacts on local communities remain contentious. A shift toward increased participation by local communities in PA governance seeks to deliver benefits for human well‐being and biodiversity. Although participation is considered critical to the success of PAs, few researchers have investigated individuals’ decisions to participate and what this means for how local people experience the costs and benefits of conservation. We explored who participates in PA governance associations and why; the perceived benefits and costs to participation; and how costs and benefits are distributed within and between communities. Methods included 3 focus groups, 37 interviews, and 217 questionnaire surveys conducted in 3 communities and other stakeholders (e.g., employees of a nongovernmental organization and government officials) in PA governance in Madagascar. Our study design was grounded in the theory of planned behavior (TPB), the most commonly applied behavior model in social psychology. Participation in PA governance was limited by miscommunication and lack of knowledge about who could get involved and how. Respondents perceived limited benefits and high costs and uneven distribution of these within and between communities. Men, poorer households, and people in remote villages reported the highest costs. Our findings illustrate challenges related to comanagement of PAs: understanding the heterogeneous nature of communities; ensuring all households are represented in governance participation; understanding differences in the meaning of forest protection; and targeting interventions to reach households most in need to avoid elite capture.  相似文献   
383.
Over the past 3 decades, indigenous guardian programs (also known as indigenous rangers or watchmen) have emerged as an institution for indigenous governments to engage in collaborative environmental governance. Using a systematic review of peer-reviewed literature for research conducted in Australia, Canada, Aotearoa-New Zealand, and the United States, we sought to characterize the emergence of indigenous guardians in the literature and explore whether guardian approaches are representative of Indigenous approaches to environmental governance. Using a multistep relevance-screening method, we reviewed 83 articles published since 1995, that report on, critique, or comment on Indigenous guardians. Our findings indicated that most articles on the topic were published in the last decade (88%), focused on Australia (65%), and were in a social science discipline (53%). The lead author of the majority of articles was an academic, although only half of the articles included an indigenous scholar or member of an indigenous group or organization as a coauthor. Finally, 11 articles were on research of guardian programs that were locally led and only 5 exemplified indigenous governance, based on 2 well-known community-based monitoring typologies. Our findings indicate that more research is required to understand the implications of current guardian programs for indigenous self-determination, particularly when such programs are embedded in a broader western environmental governance structure.  相似文献   
384.
Establishing protected areas has long been an effective conservation strategy and is often based on readily surveyed species. The potential of any freshwater taxa to be a surrogate for other aquatic groups has not been explored fully. We compiled occurrence data on 72 species of freshwater fishes, amphibians, mussels, and aquatic reptiles for the Great Plains, Wyoming (U.S.A.). We used hierarchical Bayesian multispecies mixture models and MaxEnt models to describe species’ distributions and the program Zonation to identify areas of conservation priority for each aquatic group. The landscape‐scale factors that best characterized aquatic species’ distributions differed among groups. There was low agreement and congruence among taxa‐specific conservation priorities (<20%), meaning no surrogate priority areas would include or protect the best habitats of other aquatic taxa. Common, wideranging aquatic species were included in taxa‐specific priority areas, but rare freshwater species were not included. Thus, the development of conservation priorities based on a single freshwater aquatic group would not protect all species in the other aquatic groups.  相似文献   
385.
Population viability analysis (PVA) is useful in management of imperiled species. Applications range from research design, threat assessment, and development of management frameworks. Given the importance of PVAs, it is essential that they be rigorous and adhere to widely accepted guidelines; however, the quality of published PVAs is rarely assessed. We evaluated the quality of 160 PVAs of 144 species of birds and mammals published in peer-reviewed journals from 1990 to 2017. We hypothesized that PVA quality would be lower with generic programs than with custom-built programs; be higher for those developed for imperiled species; change over time; and be higher for those published in journals with high impact factors (IFs). Each included study was evaluated based on answers to an evaluation framework containing 32 questions reflecting whether and to what extent the PVA study adhered to published PVA guidelines or contained important PVA components. All measures of PVA quality were generally lower for studies based on generic programs. Conservation status of the species did not affect any measure of PVA quality, but PVAs published in high IF journals were of higher quality. Quality generally declined over time, suggesting the quantitative literacy of PVA practitioners has not increased over time or that PVAs developed by unskilled users are being published in peer-reviewed journals. Only 18.1% of studies were of high quality (score >75%), which is troubling because poor-quality PVAs could misinform conservation decisions. We call for increased scrutiny of PVAs by journal editors and reviewers. Our evaluation framework can be used for this purpose. Because poor-quality PVAs continue to be published, we recommend caution while using PVA results in conservation decision making without thoroughly assessing the PVA quality.  相似文献   
386.
Success of animal translocations depends on improving postrelease demographic rates toward establishment and subsequent growth of released populations. Short‐term metrics for evaluating translocation success and its drivers, like postrelease survival and fecundity, are unlikely to represent longer‐term outcomes. We used information theory to investigate 25 years of data on black rhinoceros (Diceros bicornis) translocations. We used the offspring recruitment rate (ORR) of translocated females—a metric integrating survival, fecundity, and offspring recruitment at sexual maturity—to detect determinants of success. Our unambiguously best model (AICω = 0.986) predicted that ORR increases with female age at release as a function of lower postrelease adult rhinoceros sex ratio (males:females). Delay of first postrelease reproduction and failure of some females to recruit any calves to sexual maturity most influenced the pattern of ORRs, and the leading causes of recruitment failure were postrelease female death (23% of all females) and failure to calve (24% of surviving females). We recommend translocating older females (≥6 years old) because they do not exhibit the reproductive delay and low ORRs of juveniles (<4 years old) or the higher rates of recruitment failure of juveniles and young adults (4–5.9 years old). Where translocation of juveniles is necessary, they should be released into female‐biased populations, where they have higher ORRs. Our study offers the unique advantage of a long‐term analysis across a large number of replicate populations—a science‐by‐management experiment as a proxy for a manipulative experiment, and a rare opportunity, particularly for a large, critically endangered taxon such as the black rhinoceros. Our findings differ from previous recommendations, reinforce the importance of long‐term data sets and comprehensive metrics of translocation success, and suggest attention be shifted from ecological to social constraints on population growth and species recovery, particularly when translocating species with polygynous breeding systems.  相似文献   
387.
388.
Opportunity costs can represent a significant portion of the costs associated with conservation projects and frequently outstrip other kinds of cost. They are typically understood to refer to the benefits someone would have obtained if conservation projects had not required them to give up current activities, such as farming or hunting or if the land had been available for uses other than conservation. This familiar way of identifying opportunity costs is flawed, however, because it threatens to condone, or take advantage of, the injustices that many people face that affect their opportunities. I integrated ideas from the political theory of global justice to examine how the analysis of opportunity costs illustrates the importance of considering conservation and issues of global justice together, rather than thinking about them in isolation. I distinguish four baselines for defining opportunity costs. A status quo baseline defines opportunity costs by asking what people would have earned had a conservation project not happened. A willingness to accept baseline defines them by asking people what it would take to make them indifferent to whether a conservation project takes place or not. An antipoverty baseline suggests that opportunity costs have been met when people affected by a project are not left in poverty. An egalitarian baseline suggests opportunity costs have been met when people are not left in relative disadvantage, with worse than average opportunities. I argue that the egalitarian baseline is the most acceptable from the point of view of justice. Such a baseline would suggest that, in practice, many of the world's poor are being unjustly treated, or even exploited, as a result of conservation activities.  相似文献   
389.
A survey was made in an area of 28 km2 around the outlest of Ipanema's submarine outfall in order to evaluate the impact of the raw domestic sewage effluent on coastal waters. Nutrient concentrations, dissolved oxygen, particulate matter and other physico-chemical parameters were measured monthly for 15 months. Copper and lead concentrations were also determined for two of the samplings.

The outfall has been in operation for 18 years, and the parameters measured within the observation area appear to be in steady state. From the observed radial concentration gradients within the survey area, a real extension of the steady state distribution of particulate matter and of sewage-derived nitrogen was estimated. the stationary cloud of particulate organic matter was about 150 km2. From its total inventory and the discharge rate, a mean residence time of the particles in the sea of 56 days is estimated, prior to their being decomposed by bacterial action or settling to the bottom. for sewage derived N (as ammonia or nitrate), the steady state amount (above background) covers an area of about 60 km2 and leads to a mean residence time of 5 ± 1 days in the ocean. Phosphorus is readily absorbed by the phytoplankton.

The presence of temperature gradients established by cold upwelling waters controls the dispersion of the sewage material and the rising of the sewage plume to the surface waters.  相似文献   
390.
The concentration of human placental lactogen (hPL), pregnancy specific beta-1 glycoprotein (SP-1) and pregnancy-associated plasma protein A (PAPP-A) were analysed in consecutive serum samples from a patient who gave birth to a child with Cornelia de Lange syndrome. HPL and SP-1 were present in normal concentrations from week 20 to week 35 of gestation whereas PAPP-A could not be detected in any of the samples examined. Immunohisto-chemical examination of two placentae from Cornelia de Lange syndrome revealed normal localization of hPL and SP-1 but the absence of PAPP-A from the syncytiotrophoblast. The significance of association between Cornelia de Lange syndrome and compromised synthesis of PAPP-A is discussed.  相似文献   
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