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941.
基于调节聚焦理论的生物农药推广有效性研究   总被引:2,自引:0,他引:2  
化学农药在提高单位耕地面积农产品产量和效益的同时,由于过量施用、利用效率低下等污染了生态环境、危害农产品安全和损害消费者健康等问题,而具有低残留、低污染和环境友好性优势的生物农药逐渐得到公共部门和业界的重视。但生物农药能否得到大范围推广和施用,关键在于能否改变农户的农药施用行为和农药生产企业的积极参与。由于生物农药施用涉及农户的当前利益和长期利益、个人利益和社会利益等相关因素,使农户的农药施用决策具有突出的心理距离属性。本文引入调节聚焦理论,建立了心理距离与农户农药施用决策和心理动机的关系,实证研究生物农药推广对农户农药施用决策、支付愿意(WTP)、农药生产企业态度和再次施用意愿的影响。结论如下:1施用生物农药给农户带来的收益是长期的、全社会的和不确定的,而多数农户农药施用决策所考虑的利益是当前的、私人的。因此,二者在心理距离、调节聚焦以及利益追求方面是不匹配的,这揭示了当前生物农药推广过程中出现的"叫好不叫座"的原因;2农药生产企业能够从生物农药推广中获利。如果生物农药推广得当,将会提高农户对生物农药以及农药生产企业的积极评价,其对生物农药的愿意支付价格和再次施用意愿也会提升;3调节聚集信息诉求和心理距离的匹配,对农户生物农药施用决策存在显著影响。当预防(或促进)聚焦信息诉求与近(或远)心理距离匹配时,农户对生物农药信息诉求的认同度较高,施用意愿也更高。因此,要提高生物农药的推广效果,针对农户农药施用决策具有近心理距离的特点,公共部门及农药生产企业在推广生物农药时应该强化预防聚焦信息,而弱化促进聚焦信息;此外,生物农药推广过程中,公共部门及农药生产企业也可以通过宣传策略,延长农户农药施用决策时的心理距离与改善生态环境的促进聚焦目标相匹配,从而提高农户施用生物农药的积极性。  相似文献   
942.
Every year, millions of migratory shorebirds fly through the East Asian–Australasian Flyway between their arctic breeding grounds and Australasia. This flyway includes numerous coastal wetlands in Asia and the Pacific that are used as stopover sites where birds rest and feed. Loss of a few important stopover sites through sea‐level rise (SLR) could cause sudden population declines. We formulated and solved mathematically the problem of how to identify the most important stopover sites to minimize losses of bird populations across flyways by conserving land that facilitates upshore shifts of tidal flats in response to SLR. To guide conservation investment that minimizes losses of migratory bird populations during migration, we developed a spatially explicit flyway model coupled with a maximum flow algorithm. Migratory routes of 10 shorebird taxa were modeled in a graph theoretic framework by representing clusters of important wetlands as nodes and the number of birds flying between 2 nodes as edges. We also evaluated several resource allocation algorithms that required only partial information on flyway connectivity (node strategy, based on the impacts of SLR at nodes; habitat strategy, based on habitat change at sites; population strategy, based on population change at sites; and random investment). The resource allocation algorithms based on flyway information performed on average 15% better than simpler allocations based on patterns of habitat loss or local bird counts. The Yellow Sea region stood out as the most important priority for effective conservation of migratory shorebirds, but investment in this area alone will not ensure the persistence of species across the flyway. The spatial distribution of conservation investments differed enormously according to the severity of SLR and whether information about flyway connectivity was used to guide the prioritizations. With the rapid ongoing loss of coastal wetlands globally, our method provides insight into efficient conservation planning for migratory species. Gestión Óptima de una Ruta Migratoria de Múltiples Especies de Aves Costeras Sometida a Incremento del Nivel del Mar  相似文献   
943.
Forest fragments have biodiversity value that may be enhanced through management such as control of non‐native predators. However, such efforts may be ineffective, and research is needed to ensure that predator control is done strategically. We used Bayesian hierarchical modeling to estimate fragment‐specific effects of experimental rat control on a native species targeted for recovery in a New Zealand pastoral landscape. The experiment was a modified BACI (before‐after‐control‐impact) design conducted over 6 years in 19 forest fragments with low‐density subpopulations of North Island Robins (Petroica longipes). The aim was to identify individual fragments that not only showed clear benefits of rat control, but also would have a high probability of subpopulation growth even if they were the only fragment managed. We collected data on fecundity, adult and juvenile survival, and juvenile emigration, and modeled the data in an integrated framework to estimate the expected annual growth rate (λ) of each subpopulation with and without rat control. Without emigration, subpopulation growth was estimated as marginal (λ = 0.95–1.05) or negative (λ = 0.74–0.90) without rat control, but it was estimated as positive in all fragments (λ = 1.4–2.1) if rats were controlled. This reflected a 150% average increase in fecundity and 45% average increase in adult female survival. The probability of a juvenile remaining in its natal fragment was 0.37 on average, but varied with fragment connectivity. With juvenile emigration added, 6 fragments were estimated to have a high (>0.8) probability of being self‐sustaining (λ > 1) with rat control. The key factors affecting subpopulation growth rates under rat control were low connectivity and stock fencing because these factors were associated with lower juvenile emigration and higher fecundity, respectively. However, there was also substantial random variation in adult survival among fragments, illustrating the importance of hierarchical modeling for fragmentation studies. Control Estratégico de Ratas para Restaurar Poblaciones de Especies Nativas en Fragmentos de Bosque  相似文献   
944.
Despite increasing support for conservation globally, controversy over specific conservation policies persists among diverse stakeholders. Investigating the links between morals in relation to conservation can help increase understanding about why humans support or oppose policy, especially related to human–wildlife conflict or human conflict over wildlife. Yet the moral dimension of human–wildlife conflict has mostly gone unconsidered and unmeasured; thus, policy and programmatic efforts to reduce controversy may be missing a key part of the equation. We conducted a web‐based survey (n = 1239 respondents) in Michigan (U.S.A.) to investigate cognitive and emotional influences on the value–behavior relationship. Respondents were identified by their interest and involvement in Michigan wolf management. The survey consisted of questions about values, emotions, cognitions, and behaviors relative to wolves in Michigan. We used path analysis to explore whether emotions and cognitions mediated the relationship between value and behavior. Most respondents attributed intrinsic value to wolves (n = 734) and all life (n = 773) and engaged in behaviors that benefited wolf populations and ecosystems regardless of stakeholder group (e.g., environmentalist, farmer). Attributing intrinsic value to wolves was positively related to favorable emotions toward wolves and cognitive assessments that hunting and trapping of wolves is unacceptable. Despite similarities in attribution of intrinsic value, groups differed in emotions and cognitions about wolf hunting. These differences provide a useful way to predict stakeholder behavior. Our findings may inform interventions aimed at increasing support for wolf management policies and positive interactions among stakeholders and wildlife. Leveraging agreement over intrinsic value may foster cooperation among stakeholders and garner support for controversial conservation policy.  相似文献   
945.
Social and anthropological studies show a growing number of conflicts surrounding energy projects, as governments and companies insist on their implementation despite the concerns of local actors about their perceived socio-environmental risks. In this context, the purpose of this paper is to analyse the politicisation of expertise and certifications in a conflict over the construction of a combined cycle power plant by linking strategic assumptions from two particular sociological approaches. The first approach is based on the study of frame alignment in social movement organisations and the second on the translating interests in actor–network theory. These linked premises are examined in the conflict arising from the construction of a combined cycle natural gas plant in Boroa, in the Basque Country of Spain. This case study brings to light interesting findings on the strategies of the different agencies, certifications, politicisation of expertise and the increasing hostility in local conflicts.  相似文献   
946.
借鉴国内外研究成果,结合中国实际界定了引发食源性疾病的家庭食品处理风险行为,并基于10省(区)2 163户家庭的横断面抽样调查数据,以实践理论为指导,运用因子分析和聚类分析方法,实证测度家庭食品处理风险行为特征。以食源性腹泻为研究病例,利用有序多分类Logit回归模型分析了家庭食品处理风险行为特征与食源性疾病之间的关系,确定家庭食品处理的关键风险行为特征与人群特征。结果表明,对应于食品处理安全行为,家庭食品处理风险行为特征主要为食品运输、食品冷藏与剩菜处理不当,厨房清洁用品交叉污染,生熟食品交叉污染,清洁卫生风险,烹调不彻底等七种类型,且生熟食品交叉污染与剩菜处理不当是引发家庭食源性腹泻的最主要风险行为特征,尤其是男性、已婚、年龄较大、家庭人口数较少、受教育程度和职业稳定度较低、以及个人和家庭年收入水平较低的家庭人群。家庭是预防食源性疾病的最后一道防线,政府应致力于与消费者进行风险沟通,提升消费者的责任认知,采用差异化策略改善风险消费者的家庭食品处理习惯,实施抗击食源性疾病战略。  相似文献   
947.
为了科学预防并控制煤矿运输险兆事件发生,需明确煤矿运输险兆事件影响因素,以便采取相应的管控策略。在文献研究与调研访谈的基础上,运用扎根理论质性研究方法,深入分析访谈资料及煤矿运输险兆事件案例,通过开放性译码、主轴译码、选择性译码、理论饱和检验等环节对煤矿运输险兆事件影响因素进行研究。结果表明,安全培训、安全意识、监督检查等16个主范畴对煤矿运输险兆事件有影响,从中选择4个核心范畴,即运输设备系统、运输作业场所、组织管理体系、工作人员素质,概括为物理性因素与行为性因素,构建了包含2个主要因素、4个核心范畴及16个主范畴的煤矿运输险兆事件影响因素评价指标体系,最后提出了推行标准作业流程、建立管理机制、加强安全文化建设、开展闭环教育培训等策略,减少并预防煤矿运输险兆事件的发生。  相似文献   
948.
Abstract:  Understanding factors that influence the success of protected areas in curbing unsustainable resource consumption is essential for determining best management strategies and allocating limited resources to those projects most likely to succeed. I used a law-enforcement and monitoring game-theory model from the political science literature to identify three key variables useful in predicting the success of a protected area: costs of monitoring for rule breakers, benefits of catching a rule breaker, and probability of catching a rule breaker if monitoring. Although assigning exact values for each of these variables was difficult, the variables had a strong predictive capacity even when coded as coarse ordinal values. A model in which such values were used correctly predicted the outcome of 88 of 116 protected areas sampled from the peer-reviewed literature. The model identified a critical zone of common mismatch between protected-area circumstances and management policies. In situations where the costs of monitoring were greater than the product of the probability of catching a rule breaker and the benefit of doing so, conservation was unlikely to succeed. Control of illegal use of protected resources was reported in only 8% of such cases, regardless of strategies to motivate potential users to cooperate with conservation. My model does not prescribe a best management policy for conserving natural resources; rather, it can be used as a tool to help predict whether a proposed management policy will likely succeed in a given situation.  相似文献   
949.
介绍了白蚁对环境破坏程度,白蚁防治药物对环境污染和人体健康造成的严重后果;重点针对两种持久性有机污染物——氯丹和灭蚁灵的环境污染问题探讨其治理措施和处置方法。  相似文献   
950.
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