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1.
Transaction costs in community-based resource management are incurred by households attempting to enforce property right rules over common resources similar to those inherent in private property rights. Despite their importance, transaction costs of community-based management of common pool resources (CPRs) are often not incorporated into the economic analysis of participatory resource management. This paper examines the transaction costs incurred by forest users in community forestry (CF) based on a survey of 309 households belonging to eight different forest user groups (FUGs) in the mid hills of Nepal. The analysis reveals that the average 'poor' household incurred Nepalese rupees (NRS) 1265 in transaction costs annually, while wealthier 'rich' households incurred an average of NRS 2312 per year. Although richer households bear higher proportions of such costs, transaction costs for CF management as a percentage of resource appropriation costs are higher for poorer households (26%) than those of middle-wealth (24%) or rich households (14%). There are also village differences in the level of transaction costs. The results show that transaction costs are a major component of resource management costs and vary according to socio-economic status of resource users and characteristics of the community. 相似文献
2.
This study examined what factors best predict residents’ concerns about neighborhood safety. One-hundred and twenty-two participants were selected from a large, Midwestern metropolitan area. All participants lived in high crime areas. Participants completed a 22-item questionnaire that assessed their perceptions of neighborhood safety and vigilance. These items were clustered as: 1) Community care and vigilance, 2) neighborhood safety concerns, 3) physical incivilities, and 4) social incivilities. Police crime data were also used in the analyses. Our findings suggest that aspects of the broken window theory, collective efficacy, and place attachments/territoriality play a role in affecting residents’ concerns about neighborhood safety. 相似文献
3.
Collective payments for ecosystem services (PES) programs make payments to groups, conditional on specified aggregate land-management outcomes. Such collective contracting may be well suited to settings with communal land tenure or decision-making. Given that collective contracting does not require costly individual-level information on outcomes, it may also facilitate conditioning on additionality (i.e., conditioning payments upon clearly improved outcomes relative to baseline). Yet collective contracting often suffers from free-riding, which undermines group outcomes and may be exacerbated or ameliorated by PES designs. We study impacts of conditioning on additionality within a number of collective PES designs. We use a framed field-laboratory experiment with participants from a new PES program in Mexico. Because social interactions are critical within collective processes, we assess the impacts from conditioning on additionality given: (1) group participation in contract design, and (2) a group coordination mechanism. Conditioning on above-baseline outcomes raised contributions, particularly among initially lower contributors. Group participation in contract design increased impact, as did the coordination mechanism. 相似文献
4.
Gwendolyn Ricco 《Journal of Environmental Policy & Planning》2019,21(3):275-287
ABSTRACTLearning is critical for land management agencies implementing new policies in the face of rapid social and ecological change. We investigated learning in the U.S. Forest Service as it implemented new planning regulations. Our research objectives were to: (1) identify collective learning processes and outcomes during this time, and (2) understand factors within the organization supporting or impeding learning. Based on participant observation and 25 interviews with planning personnel, we found evidence of collective learning on individual national forests and across the organization. Several factors helped the agency act as a ‘learning organization,’ including internal networks and tools for information sharing, and meetings for staff to exchange lessons learned. Learning was compromised by limited time and capacity, and lack of internal clarity about balancing the desire for innovation with the need to ensure legal compliance and meet deadlines. This work contributes to the empirical foundations of collective learning theory, allowing us to identify learning processes and outcomes at multiple levels in a public organization, and identifying topics for future research. Based on our exploration of organizational learning, we offer suggestions for how to effectively support learning during times of new policy implementation. 相似文献
5.
Samuel R. Scholes Ana B. Sendova-Franks S. Tim Swift Chris Melhuish 《Behavioral ecology and sociobiology》2006,59(4):531-540
A fundamental issue of collective intelligence is whether the collective pattern or process is based on environmental information
that explicitly codes for it or arises through self-organization of the individuals. Sometimes, these alternatives occur together.
Adaptive systems may also be capable of utilizing different types of mechanism under different conditions. Sendova-Franks
et al. (Anim Behav 68:1095–1106, 2004) demonstrated evidence for a self-organization mechanism of brood sorting in the ant
Temnothorax albipennis, where the brood are sorted in a series of bands or concentric annuli that increase in size with distance from the colony
centre. The work by Cox and Blanchard (J Theor Biol 204:223-238, 2000) suggests an alternative or complementary mechanism
whereby the brood pattern is specified by the template of a CO2 gradient. Here, we test for a gaseous template as a necessary condition for brood sorting. Under the experimental condition,
we pumped the air out of the nest continuously to prevent the accumulation of any gaseous substances. We compared the brood
pattern between the experimental and control conditions according to four characteristics: mean distance from centre, mean
nearest-neighbour distance, shape and area. Under the experimental condition, the order of brood types according to the first
two characteristics was the same as in the control. The area of the brood pattern was smaller, and its shape elongated under
the experimental condition. As expected on the basis of these differences, mean distance from centre was greater and mean
nearest-neighbour distance was smaller under the experimental condition (although not statistically significantly) and by
the expected amount. We found evidence that ants avoid placing brood in the strongest airflow stream. This could explain the
reduced area and elongated shape of the brood pattern under the experimental condition. We conclude that a gaseous template
is not a necessary condition for brood sorting.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
6.
Audrey Dussutour Stamatios C. Nicolis Jean-Louis Deneubourg Vincent Fourcassié 《Behavioral ecology and sociobiology》2006,61(1):17-30
In this paper we examine the effect of crowding on the selection of a path in the mass-recruiting ant Lasius niger. In our experiment, ants had to go from their nest to a food source by crossing a diamond-shaped bridge, giving the choice between two paths. Two types of bridges were used: the first had two branches of equal length but different width while the second had two branches of different length and width. Experiments at high traffic volume always ended up with the selection of the wider branch, even if it was longer. This result shows that overcrowding on the narrow branch plays an essential role in the mechanism underlying the choice of route in ants. A mathematical model was developed to evaluate the importance of two mechanisms that could account for this result. The first is based on the difference in travel duration between the two paths. The second is based on the repulsive interactions between workers making head-on encounters. The model shows that travel duration per se is not sufficient to explain path choice. Rather, it is the interplay between trail following behaviour and repulsive interactions that allows ants to choose the path that minimizes their travel time. When choosing a path ants thus prefer to trade time against energy. Our results demonstrate that any environmental constraint that alters the dynamics of trail recruitment can lead to the emergence of adaptive foraging decisions without any explicit coding of information by the foragers at the individual level. 相似文献
7.
地震动在强度和频率等方面均具有非平稳特性,导致多跨桥梁的动力响应非常复杂.为了研究多跨连续桥梁在多点地震动激励下的反应,首先提出了评价多点地震动非平稳性的3个指标:幅值绝对值的标准差、方向离散度和穿零率.根据桥梁多点激励运动方程的特点,阐述了广义振型参与系数矩阵的意义,及其与传统振型参与系数矩阵的联系和区别.根据多点地... 相似文献
8.
Elizabeth A. Langridge Ana B. Sendova-Franks Nigel R. Franks 《Behavioral ecology and sociobiology》2008,62(3):447-456
Certain groups of organisms are capable of improving their collective performance with experience. In a recent study, we demonstrated
that, over successive emigrations, colonies of the ant Temnothorax albipennis are able to improve their collective performance by reducing the time taken to complete an emigration (Langridge et al.,
Behav Ecol Sociobiol 56:523–529, 2004). In this paper, by recording the performance of individually marked workers during
repeated emigrations, we were able to analyse some of the ways in which time gains are achieved. We found that: (1) those
transporters that also transported in the preceding emigration began to transport earlier in the current emigration and, in
the majority of emigrations, transported more items than those transporters that had not transported in the preceding emigration;
(2) the time that elapsed before the first item was transported into the new nest reduced over successive emigrations, and
this first item was, in the majority of emigrations, carried by a transporter that had also transported in the preceding emigration;
(3) the number of adults that were transported reduced over successive emigrations. Our results strongly suggest that the
behaviour of transporters that also transported in a preceding emigration may be modified as a result of their experience
and that, consequently, their efforts in the next emigration make a major contribution to the improved performance of the
colony as a whole. 相似文献
9.
空间相关性对大跨度空间结构的影响不容忽视。本文采用动力时程分析方法对圆柱面巨型网格结构进行了多点激励下的地震响应分析,并与一致激励下的结构地震响应进行对比,探讨了主体结构单独承载和子结构参与协同承载这2种情况下,不同行波激励对结构关键节点和杆件响应的影响及其变化特点;通过比较分析结构在多点激励和一致激励下的响应差异,得出圆柱面巨型网格结构在地震输入时需考虑多点激励的结论,可供该类结构的抗震设计参考。 相似文献
10.
“苏南模式”是我国目前经济发展模式之一,取得了巨大的成就,也面临着严峻的挑战。实施可持续发展战略是“苏南模式”摆脱传统再创辉煌的必然选择,可将苏南地区建成我国可持续发展示范区。 相似文献