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71.
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
72.
The numerous formulated products which are introduced to the market consist of chemical ingredients that may cause various safety and health hazards to the consumers. Therefore, it is extremely important to practice a systematic methodology to formulate products with acceptable safety and health performances. This work presents an index-based methodology to assess the safety and health hazards of the ingredients during the early formulation stage of product design. Hence, new inherent safety and health sub-indexes are introduced to improve the current safety and health hazards that are needed in formulated product design. The inherent safety and health sub-indexes are assigned with scores based on the degree of potential hazards. A higher score indicates a higher safety risk or severe health effect, and vice versa. The proposed methodology will greatly assist the users to identify the adverse safety and health effects caused by the ingredients. Hence, it is pivotal to eliminate or reduce the safety and health impacts from product usage. A case study on common ingredients used in the formulation of paint is presented on this study to describe the proposed method. 相似文献
73.
Hugh Begg Greg Lloyd David Newlands 《Journal of Environmental Planning and Management》1989,32(2):101-105
This article discusses the structure and performance of Work‐Start Ltd., a company located in Dundee and providing training for the unemployed. The company has attracted national and international attention by its innovative approach. Set up to meet the specific problems of peripheral housing estates, it is now responding to rapid changes in the local labour market. 相似文献
74.
厦门海域防控陆源污染的实践与经验 总被引:2,自引:0,他引:2
在分析厦门海域主要污染物来源的基础上,总结了厦门市针对不同来源的水污染物开展的治理措施,并重点介绍了厦门市关于化工废水、电镀废水、生活污水和养殖废水的处理与利用的4个典型实例.厦门市在防治陆源污染的实践中,逐渐形成并发挥重要作用的5项机制,即管理机制、组织协调机制、法规保障机制、科技进步机制、经济激励机制. 相似文献
75.
调质碳酸钙硫化机理的实验研究 总被引:3,自引:0,他引:3
对经Na2CO3溶解调质后石灰石煅烧、硫化特性进行了研究,发现调质后石灰石比未经调质石灰石具有更快的煅烧分解速率。CO2浓度变化对调质CaO硫化效果的影响程度要比未经调质CaO更为明显。调质CaO比调质前具有更高的最终钙转化率,但脱硫剂微观结构测定表明,调质CaO比表面积和孔隙率均小于同等条件下获得的未经调质CaO比表面积和孔隙率。利用X-衍射技术对CaO晶体结构进行了测定,对比晶格畸变度等参数并综合煅烧、硫化及脱硫剂孔特性,提出了调质CaO硫化反应机理为:前期为化学反应控制阶段,后期为离子扩散控制阶段。应用分形理论对CaO分形维数进行了计算,发现随CO2浓度的增加,无论调质与否得到的CaO,分形维数均呈下降趋势。 相似文献
76.
We investigated competition for food among two groups of six clone amagos (salmonids), Oncorhynchusmasoumacrostomus, in a laboratory experiment with different rates of food input. We examined the effect of temporal clumping of food resources
on the inequality of food sharing between competitors. Monopolization of food by dominants was greater at a low input rate
(one food item per 10 s) than at a high input rate (1 food item per 1 s). Aggressive behavior by dominants was more frequent
at the low input rate than at the high input rate; its purpose was presumably to interfere with the feeding behavior of subordinates.
We assessed the relative importance of three foraging factors (the number of approaches to food items, the chance per approach
and the gain per chance) in enhancing inequality in food gain between individuals. Dominants had a disproportionately high
chance per approach and gain per chance at the low input rate, but not at the high input rate. The chance of obtaining a food
item per approach depended on how many competitors approached simultaneously. The gain per chance depended on the competitive
ability of the approaching fish. There was an interaction between these components, such that the number of approaches affected
the chance per approach and gain per chance. We evaluated the independent effect of the chance per approach, and showed that
it was higher for dominants than for subordinates at the low input rate, but not at the high input rate. This implies that
subordinates changed their behavior and became more likely to avoid approaching food at the same time as dominants at the
low input rate.
Received: 13 August 1996 / Accepted after revision: 30 November 1996 相似文献
77.
This paper examines the determination of effort levels, the rental price of quotas and the number of participants in a fishery managed with a total allowable catch and individual transferable quotas. How these variables change is determined for three phases of the management process. Potential participants in the fishery are assumed to be heterogeneous in their catching capabilities so that almost all active fishers earn positive net profits from fishing activities. It is shown that these quasirents are reduced during any of the management phases considered here. The impact of free allocations of permanent quota rights on fishers’ welfare is also considered. This may increase the welfare of all fishers if the allocation is based on catch history. However, an example is provided where the welfare of some highliners is reduced when the allocation is based on effort history. 相似文献
78.
One mechanism that permits the maintenance of dominance hierarchies is individual recognition, defined as the ability of an animal to recognize a conspecific on the basis of one or more identifying cues, and to associate it with experiences of victories or defeats that the animal has gained from preceding encounters with that particular individual. We examined whether the long-clawed hermit crab, Pagurus longicarpus, could differentiate between unfamiliar and familiar opponents. The experimental protocol was designed to control in pairs of interacting individuals several factors together, such as status and relative size of the opponent, as well as species, quality, and fit of the inhabited shell. The hermit crabs were more reactive and their agonistic level was higher in unfamiliar than in familiar pairs; in addition, betas were more prone to initiate an interaction with unfamiliar than with familiar alphas. The alternative explanation—that the ability to discriminate between familiar and novel shells can explain our results per se— was tested following, in part, Jackson and Elwoods (1989) protocol for Pagurus bernhardus and was, at least for this species, rejected. This study did not determine whether a true individual recognition occurs, but demonstrated that P. longicarpus categorizes the individuals into two heterogeneous subgroups, thus being capable of a binary discrimination among opponents.Communicated by T. Czeschlik 相似文献
79.
Over the last decade, adaptive co‐management has been recommended as a policy framework to address complex and uncertain resources management issues. Implementing this theoretical management concept requires the integration of multidisciplinary research and local knowledge. Yet practical protocols to link science, policymaking and societies have yet to be developed. We designed a protocol to produce legitimate, credible and relevant solutions to a regional resources management issue. This is a two‐component protocol. A stakeholder grid categorizes stakeholder representatives in three distinct specialized dialogue arenas: institution representatives, technical experts and local end‐users. An iterative co‐design process then builds on these arenas to assess the institutional legitimacy, technical credibility and empirical relevance dimensions of a common solution initiated by an initial plausible promise. We tested this framework in Réunion to address organic waste management issues at the regional level. The plausible solution explored was the introduction of a recycling industry involved in collecting organic waste and producing and selling organic fertilizers tailored for local crop systems. The protocol application outcomes were consolidated and documented scenarios accepted by all, with knowledge exchange and the broad spread of a stabilized expectation contributing to private initiatives and public policy change. 相似文献
80.
C. Nathan Jones Ali Ameli Brian P. Neff Grey R. Evenson Daniel L. McLaughlin Heather E. Golden Charles R. Lane 《Journal of the American Water Resources Association》2019,55(3):559-577
Representing hydrologic connectivity of non‐floodplain wetlands (NFWs) to downstream waters in process‐based models is an emerging challenge relevant to many research, regulatory, and management activities. We review four case studies that utilize process‐based models developed to simulate NFW hydrology. Models range from a simple, lumped parameter model to a highly complex, fully distributed model. Across case studies, we highlight appropriate application of each model, emphasizing spatial scale, computational demands, process representation, and model limitations. We end with a synthesis of recommended “best modeling practices” to guide model application. These recommendations include: (1) clearly articulate modeling objectives, and revisit and adjust those objectives regularly; (2) develop a conceptualization of NFW connectivity using qualitative observations, empirical data, and process‐based modeling; (3) select a model to represent NFW connectivity by balancing both modeling objectives and available resources; (4) use innovative techniques and data sources to validate and calibrate NFW connectivity simulations; and (5) clearly articulate the limits of the resulting NFW connectivity representation. Our review and synthesis of these case studies highlights modeling approaches that incorporate NFW connectivity, demonstrates tradeoffs in model selection, and ultimately provides actionable guidance for future model application and development. 相似文献