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991.
Dustin Mulvaney 《Journal of Land Use Science》2017,12(6):493-515
Utility-scale solar energy (USSE) development is an emerging cause of land use change across the American Southwest. Many proposed projects in the region have encountered resistance from environmental groups because of concern about endangered, threatened, and special status species. Projects have also faced resistance from impacted local communities and Native American tribes. This research documents land use conflicts that surfaced during the initial wave of USSE development from 2009 to 2015. The goal is to identify potential roots of land use conflict over renewable energy development, to help explain why there is consistent support for renewables in general, but widespread opposition to projects during the proposal and development stages. The primary data presented include public comments to formal rule-making processes, semi-structured interviews conducted from 2009 to 2013, and various media sources. The paper concludes describing emerging planning frameworks that identify sites for USSE with fewer land use conflicts. 相似文献
992.
This study was conducted to determine the patterns and drivers of forest land cover changes in Bobiri and Oboyow Forest Reserves (BFR and OFR, respectively), Ghana. Landsat images were employed to determine forest land cover types and changes in 1990, 2000 and 2010 using supervised classification method. Factors that drive forest land cover changes in the forest reserves were determined using a semi-structured questionnaire and field observations. Generally, closed-canopy forest decreased by 49% in both forests over 20-year period resulting in a tremendous increase in open-canopy forest (BFR: 85%; OFR: 46%) and non-forest land cover types (BFR: 48–80% OFR: 127–350%). Factors such as logging manual illiteracy among timber operators, offences of authorised timber operators, ineffective community participation, harvesting schedule revision, chainsaw logging, illegal logging, bushfires, fuel gathering and weak penalty for offences were identified as contributing to rapid depletion of closed canopy forest cover in the forest reserves. 相似文献
993.
Tomas Jusys 《Journal of Land Use Science》2017,12(2-3):125-137
A widely discussed assumption that the expansion of sugarcane indirectly contributes to deforestation in Brazil has been backed statistically by only a handful of studies. The present research measures the indirect effect of sugarcane in Brazil’s frontier counties as a weighted summation of changes in sugarcane area in agricultural (non-frontier) counties, where weights are constructed using road distances and the bandwidth that minimizes overall model error. In addition to economic variables, indirect effect variables are employed to create a model that explains deforestation. Parameters are estimated following fixed-effects methodology. The results reveal that sugarcane indirectly contributed to deforestation in Brazil during the period from 2002 to 2012. The effect was estimated to be sizeable; in particular, 16.3 thousand km2 of forest was cut by economic actors displaced by expanding sugarcane plantations. This figure constitutes 12.2% of deforestation in Brazil from 2002 to 2012 and is equivalent to 189.4 million Mg of carbon emissions. 相似文献
994.
Catrien J.A.M. Termeer Art Dewulf G. Robbert Biesbroek 《Journal of Environmental Planning and Management》2017,60(4):558-576
Although transformational change is a rather new topic in climate change adaptation literature, it has been studied in organisational theory for over 30 years. This paper argues that governance scholars can learn much from organisation theory, more specifically regarding the conceptualisation of change and intervention strategies. We reconceptualise the divide between transformational change and incremental change by questioning the feasibility of changes that are concurrently in-depth, large scale, and quick; and the assumption that incremental change is necessarily slow and can only result in superficial changes. To go beyond this dichotomy, we introduce the conceptualisation of continuous transformational change. Resulting intervention strategies include (1) providing basic conditions for enabling small in-depth wins; (2) amplifying small wins through sensemaking, coupling, and integrating; and (3) unblocking stagnations by confronting social and cognitive fixations with counterintuitive interventions. These interventions necessitate a modest leadership. Governing transformational change thus requires transformation of the governance systems themselves. 相似文献
995.
This paper investigates the extent and the nature of how the urban planning literature has addressed climate change adaptation. It presents a longitudinal study of 157 peer-reviewed articles published from 2000 to 2013 in the leading urban planning and design journals whose selection considered earlier empirical studies that ranked them these journals. The findings reveal that the years 2006–07 represent a turning point, after which climate change studies appear more prominently and consistently in the urban planning and design literature; however, the majority of these studies address climate change mitigation rather than adaptation. Most adaptation studies deal with governance, social learning, and vulnerability assessments, while paying little attention to physical planning and urban design interventions. This paper identifies four gaps that pertain to the lack of interdisciplinary linkages, the absence of knowledge transfer, the presence of scale conflict, and the dearth of participatory research methods. It then advocates for the advancement of participatory and collaborative action research to meet the multifaceted challenges of climate change. 相似文献
996.
A fresh perspective on policy-making and planning has emerged which views disproportionate policy as an intentional policy response. A disproportionate policy response is understood to be a lack of ‘fit’ or balance between the costs of a public policy and the benefits that are derived from this policy, and between policy ends and means. This paper applies this new perspective on the proportionality of policy-making to the area of climate change. The first part of the paper discusses the underlying causes of disproportionate policy responses in broad terms and then applies the theoretical reasoning to understand the conditions in which they are likely to appear in relation to climate change. These conditions are hypothesized to relate to four main factors: economic considerations; levels of public demand; focusing events; and strategic considerations. It concludes with the suggestion that societal actors may be able to manipulate these four factors to encourage politicians to adopt policies that mitigate climate change more rapidly than is currently the case in most countries. 相似文献
997.
Jin Zhang Qiang Yang Xiaofei Song Hui Qiao Junhao Zhang 《International Journal of Green Energy》2017,14(12):1011-1019
Electrospun cellulose acetate (CA) nanofibrous mats incorporated with capric acid was studied to fabricate form-stable phase change materials (PCMs) for storing/retrieving thermal energy. Electrospun CA nanofibrous mats with different porous structures and specific surface areas were firstly prepared through regulating the volume ratio of mixture solvent of acetone/dichloromethane (DCM). Effects of different volume ratio of mixture solvent and mat thickness on the morphological structure, specific surface area, and absorption capacity of CA nanofibrous mats were systematically investigated. The results indicated that CA nanofibrous mats were highly porous on the surface; hence, they were capable of absorbing a large amount of capric acid. The maximum absorption capacity of CA mats via electrospinning with volume ratio of acetone/DCM being 5/5 was ~95.8 wt%, due to its higher specific surface area of ~17.1 m2/g. The specific surface area and capric acid absorption capacity of CA nanofibrous mats increased with the increases of mat thickness. As the thickness of nanofibrous mats increased from 10 to 85 μm, the corresponding specific surface area and capric acid absorption capacity of mats increased respectively from 7.2 to 29.0 m2/g and 92.1 to 98.5%. Morphological structures, as well as the properties of thermal energy storage and thermal insulation of the fabricated form-stable PCMs, were studied by scanning electron microscopy, differential scanning calorimetry, and measurement of freezing times, respectively. The results indicated that the resulting form-stable PCMs could well maintain their phase transition characteristics and demonstrated great thermal energy storage capability and temperature regulation ability. 相似文献
998.
Mert Gürtürk Ahmet Koca Yasin Varol Mehmet Şekerci 《International Journal of Green Energy》2017,14(12):1073-1080
Solar energy is one of the most important renewable energy sources, but it is not available every time and every season. Thus, storing of solar energy is important. One of the popular methods of heat storage is use of phase change materials (PCMs) which have large thermal energy storage capacity. In this study, the heat storage tank in a domestic solar water heating system was chosen as control volume. The experiments were performed in the province of Elaz?g, Turkey, in November when solar radiation was weak due to cloudy sky. The heat storage tank of the system was modified to fill PCM between insulation and hot water part. A few PCMs which are Potassium Fluoride, Lithium Metaborate Dihydrate, Strontium Hydroxide Octahydrate, Barium Hydroxide Octahydrate, Aluminum Ammonium Sulfate, and Sodium Hydrogen Phosphate were analyzed to proper operating conditions using a Differential Scanning Calorimeter (DSC) and the best PCM was obtained with the Aluminum Ammonium Sulfate and Sodium Hydrogen Phosphate mixture. Thus, eutectic PCM was obtained and used in a heat storage tank of the solar water heating system. Energy and exergy analysis of heat storage tank was performed with and without the PCM. Energy and exergy analysis has shown that the heat storage tank with the PCM is more efficient than without the PCM and the maximum exergy efficiency was obtained as 22% with the heat storage tank with the PCM. 相似文献
999.
全球气候变化的研究与进展 总被引:14,自引:2,他引:12
论述了全球气候变化的研究目标、方法、主要科学问题及近10年来国内外的研究进展和存在的主要问题。指出中国是全球的一个组成部分,又是人类活动最为强烈的地区之一,在全球气候变化、特别是人类活动诱发的气候变化的研究中占有十分重要的地位。建议大力加强全球气候变化的研究,增加研究经费的投入,积极参与国际科学合作,把当前较为分散的研究有效地组织到一些有前景的、能出高水平成果的课题上去,为全球气候变化研究做更大的贡献。 相似文献
1000.
长白山北坡林线处岳桦年轮年表及其与气候的关系 总被引:1,自引:0,他引:1
运用相关函数及响应分析等树木年轮气候学方法,研究了长白山北坡林线处岳桦(Betula ermanii)径向生长及其与气候的关系.结果表明,林线处岳桦年轮宽度年表具有较强的气候敏感性.其径向生长与上年7月和当年3月的温度显著负相关(P<0.05),与上年9月和当年7月的温度显著正相关;同时与上年6月降水量显著正相关.与季节性气候因子的响应分析表明,岳桦径向生长与当年春季(1~3月)和当年生长季前(4、5月)的平均温度呈显著负相关,与当年生长季前的平均最高温度显著正相关,与降水量的相关关系不显著.利用多元逐步回归方法模拟了岳桦年轮宽度指数与气候因子间的关系,并据此预测在温度和降水增加的背景下,林线处岳桦径向生长将降低14.8%. 相似文献