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691.
Patrick Hitayezu Edilegnaw Wale Gerald F. Ortmann 《Environment, Development and Sustainability》2016,18(4):985-1003
On-farm tree cultivation is considered an important strategy to mitigate detrimental environmental impacts of agricultural land-use change (ALUC). In South Africa, however, little is known about farm-level incentives and constraints that govern ALUC decisions among small-scale farmers. To address this knowledge gap, this study employs a mixed multinomial logit model by using a combination of revealed and stated preference data. After correcting for endogeneity, the estimated results show that decisions about ALUC are rationally derived and driven by clear but heterogeneous preferences and trade-offs between crop productivity, food security and labour saving. The results further show that the decision to plant sugarcane is constrained by landholding, whilst farmland afforestation is negatively influenced by household size. Decisions to convert land use are also driven by the behaviour of peer groups and agro-ecological conditions. Based on these findings, important policy implications for sustainable land use are outlined. 相似文献
692.
Syed A. Shah Dana L. K. Hoag Stephen Davies 《Environment, Development and Sustainability》2016,18(4):1081-1093
This two-part study investigates household preferences and willingness to pay (WTP) for water quality improvement of the Swat River in Pakistan. First, a four-point Likert scale was used to rank preferences for water quality benefits without using any financial metric. Results show that households have comparatively strong preferences for non-use benefits. Second, a contingent valuation question was designed to determine WTP for adopting a management plan developed exclusively for water quality improvement in the Swat River. The estimated annual mean WTP per household for water quality improvement is $2.40 when donating to an NGO. Generalizing this value to households living in Swat Valley would generate up to $544,000 per year. The present value aggregate benefit for 15 years would be sufficient to cover the present value of aggregate costs to adopt the management plan. A mandatory program that would require paying for the management plan generates half the WTP compared to the voluntary plan, but is still sufficient to cover costs and may be more feasible than a voluntary program because payment is assured. 相似文献
693.
Larval amphibians are particularly likely to encounter variation in rearing temperature and resource availability due to variation in aquatic breeding habitats. In this study, plasticity in growth rates, larval mass, larval period, and size at metamorphosis were examined in Rana kukunoris Nikolskii, 1918 under different combinations of temperature and food level. Larval period and larval body mass was sensitive to food level, and varied with temperature. Tadpoles metamorphosed at an older age at low temperature than those reared at warm temperature. Food level was a significant affect on larval period at low temperature, but not at warm temperature. Mass was heavier for tadpoles reared at low temperatures than those reared at warm temperatures. The effect of food level depended on temperature, because larvae reared at low temperature that were offered a high food level achieved a larger size than larvae offered a low food level, but this did not occur at warm temperature. Therefore, we suggest that high food availability at low temperature prolonged developmental periods, thus larvae are larger as metamorphs than those reared at warm temperatures. 相似文献
694.
Relationships between stem diameter and phytomass of trees and their parts (single- and multistemmed growth forms) have been studied at different altitudinal levels of the present-day upper treeline ecotone on the Iremel’ Massif, the Southern Urals. The time course of changes in the structure and phytomass of birch–spruce stands during the past centuries has been reconstructed. It is shown that the expansion of forests to the mountains in this period has occurred against the background of rise in summer and winter temperatures and increase in the amount of solid precipitation in the Southern Urals. 相似文献
695.
V. G. Tereshchenko D. S. Khrystenko G. O. Kotovska L. I. Tereshchenko 《Russian Journal of Ecology》2016,47(4):364-370
The probable source of stone moroko, Pseudorasbora parva (Temminck & Schlegel, 1846), populations in lake- and stream-type Dnieper reservoirs was revealed. The dynamics and specific growth rates of these populations over 20 years were analyzed. The dynamic phase portrait method was used to determine the timing of stages in the process of invader naturalization and the periods when its populations were in equilibrium. The potential growth rates of P. parva populations in the Kremenchug and Dneprodzerzhinsk reservoirs were estimated. 相似文献
696.
L. E. Yalkovskaya M. A. Fominykh S. V. Mukhacheva Yu. A. Davydova A. V. Borodin 《Russian Journal of Ecology》2016,47(3):281-288
Fluctuating asymmetry (FA) of the mandible shape has been analyzed in bank voles from the zones affected by pollution from three copper smelters in the Urals. It has been shown that there is the necessity for a detailed analysis of the material, since the level of FA may depend on population parameters. Regardless of the pollution level, FA of the mandible region including the lower part of the mandibular body, ramus and processes is higher than in the diastema region. A gradient effect of toxic exposure on FA has been revealed: an increase in its level under increasing technogenic impact is clearly manifested along local pollution gradients. 相似文献
697.
Hallie Eakin Abigail York Rimjhim Aggarwal Summer Waters Jessica Welch Cathy Rubiños Skaidra Smith-Heisters Chrissie Bausch John M. Anderies 《Regional Environmental Change》2016,16(3):801-814
The prospect of unprecedented environmental change, combined with increasing demand on limited resources, demands adaptive responses at multiple levels. In this article, we analyze different attributes of farm-level capacity in central Arizona, USA, in relation to farmers’ responses to recent dynamism in commodity and land markets, and the institutional and social contexts of farmers’ water and production portfolios. Irrigated agriculture is at the heart of the history and identity of the American Southwest, although the future of agriculture is now threatened by the prospect of “mega-droughts,” urbanization and associated inter-sector and inter-state competition over water in an era of climatic change. We use farm-level survey data, supplemented by in-depth interviews, to explore the cross-level dimensions of capacity in the agriculture–urban nexus of central Arizona. The surveyed farmers demonstrate an interest in learning, capacity for adaptive management and risk-taking attitudes consistent with emerging theory of capacity for land use and livelihood transformation. However, many respondents perceive their self-efficacy in the face of future climatic and hydrological change as uncertain. Our study suggests that the components of transformational capacity will necessarily need to go beyond the objective resources and cognitive capacities of individuals to incorporate “linking” capacities: the political and social attributes necessary for collective strategy formation to shape choice and opportunity in the future. 相似文献
698.
Anna Rolewicz-Kalińska Anna Oniszk-Popławska Judyta Wesołowska Elżbieta D. Ryńska 《Environment, Development and Sustainability》2016,18(5):1279-1296
This article outlines problems related to the location of facilities designed to treat the organic fraction of municipal solid waste (OFMSW). Anaerobic digestion (AD) facilities are investigated as a treatment option, while taking into account the aspects of renewable energy generation. This research has been spurred on by the relationship between waste management, energy generation issues and spatial planning procedures. The analysis is focused on urban and semi-urban areas of medium and large cities. One of the most difficult issues associated with siting of waste processing plants is its integration with local infrastructures, avoiding conflicts and negative environmental impacts at the same time. This research aims to analyse possible locations for AD plants fuelled by OFMSW in Poland. Based on the experience gained from other countries and lessons learnt from the analysis of existing facilities in Europe, conditions for the location of this type of waste treatment plants have been defined, with the focus on economic, environmental and social issues. Most likely, the results of the multicriteria decision analysis for siting of municipal solid waste AD plants (M-BIST tool) could be transferred to other countries, especially those with a comparable GDP level and a similar framework for a waste management system. 相似文献
699.
Ian M. Picketts Jean Andrey Lindsay Matthews Stephen J. Déry Susan Tighe 《Regional Environmental Change》2016,16(4):1109-1120
Transport infrastructure is particularly vulnerable to climate impacts as it is designed for long operational lives, and both episodic and seasonal conditions contribute to deterioration, disruption and unsafe incidents. There are some examples of adaptation in transportation design, but many communities do not have the capacity to incorporate climate change considerations into infrastructure planning and management. Researchers worked closely with the City of Prince George, in Central British Columbia, Canada, to build on existing work and explore how the City could plan, design, and maintain roads and other structures to account for climate change. A local steering committee was formed, and created and evaluated 23 potential research topics. Two focus areas were selected for further investigation and explored during a workshop with practitioners, researchers, consultants and other representatives. The workshop precipitated an investigation of projected impacts of climate change on road maintenance and road safety, and plans to explore alternative paving techniques. Outcomes of the case study provide insights regarding climate change and local transportation infrastructure, including: how researchers can engage with local experts to explore adaptation; issues local governments perceive as important; and barriers communities face as they attempt to address vulnerabilities. 相似文献
700.
Jennifer H. Westerman James W. Westerman Brian G. Whitaker 《Environment, Development and Sustainability》2016,18(2):561-576
Recent conjecture on the potential primacy of physical environmental components in education for sustainable development (ESD) efforts serves to question the centrality of social justice education as a component of ESD. This research explores a sustainable development student’s basic knowledge of social justice conditions in their country of residence and its relationships to policy attitudes that should be of importance to ESD, including beliefs about the importance of corporate social responsibility, their endorsement of gross national product as an effective measure of progress, their overall assessment of the social fairness of current national social justice policy, and their endorsement of the goals of Occupy Wall Street. Results obtained using path-model hypothesis testing indicate that accuracy of knowledge of US standing on social justice issues is significantly related to these policy attitudes, providing support for social justice content in ESD endeavors to create students empowered for engagement in broader policy goals. 相似文献