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101.
南方丘陵山区典型地物景观特征尺度研究   总被引:5,自引:1,他引:4  
景观的特征尺度反映了人与自然交互作用的空间过程,合理识别景观空间结构及其特征尺度有助于遥感影像景观空间异质性分析。论文以地处南方丘陵山区的福建省福州市为研究区,针对城市、农田、森林与水域4种地物景观,基于SPOT 10 m影像,分别利用半方差分析、小波分析与平均局部方差方法,开展景观特征尺度研究。结果表明:①不同景观类型的空间异质性差异较大,其中森林景观空间异质性最大,其次为城市、农田景观,水域的空间异质性最小;②小波方差分析和半方差分析分别检测到两个不同的特征尺度,而局部方差仅仅检测到较小的空间结构;③森林景观特征尺度比通常偏小,与南方丘陵山区破碎地形有关,城市景观更多体现为人类活动的影响,南方丘陵山区城市景观至少具有两种不同的空间结构,其特征尺度均较小,农田景观特征尺度最大。基于小波分析与半方差各自的特点,总结提炼出综合两种方法合理识别景观特征尺度的基本流程,即:首先开展小波分析,然后在此基础上利用半方差分析多种理论模型组合从而获得更详细的特征尺度信息,模型组合个数与参数初始值依据小波分析的结果而定。  相似文献   
102.
区域COD、SO_2及TSP排放的空间自相关分析:以江苏省为例   总被引:6,自引:1,他引:5  
空间自相关分析是空间统计学的一个重要组成部分,是认识空间格局的有效手段.针对研究的空间范围不同,常采用全局空间自相关和局部空间自相关来衡量区域空间自相关程度.利用江苏省1990~2006年13个省辖市COD、SO2和TSP排放量数据,采用空间自相关分析方法对江苏省环境污染排放区域异质性进行了研究.结果表明,江苏省COD和TSP排放总量分别从1990年的596 353 t和1 101 404 t显著下降到2006年的291 762 t和704 734 t,SO2排放量基本保持稳定;江苏省COD、SO2和TSP排放的空间自相关性随时间推移正在发生着变化,到2006年COD、SO2和TSP排放的Global Moran’s I分别达到0.465 7、0.214 2和0.510 1,呈现较显著的正空间自相关趋势,空间上的集聚分布格局业已形成,且COD排放先于SO2和TSP排放在空间呈现集聚格局,空间集聚的程度也较大;苏南与苏北的污染排放格局差异较大,苏南COD、SO2和TSP排放的Global Moran’s I值至2006年分别增加到0.499 7、0.320 2和0.298 3,集聚格局明显,而苏北COD、SO2...  相似文献   
103.
An attempt has been made to produce stable water–diesel emulsion with optimal formulation and process parameters and to evaluate the performance and emission characteristics of diesel engine using this stable water–diesel emulsion. A total of 54 samples were prepared with varying water/diesel ratio, surfactant amount and stirring speed and water separation was recorded after 24 and 48 hr of emulsification. The recorded data were used in artificial neural network (ANN)-particle swarm optimization (PSO) technique to find the optimal parameters to produce water–diesel emulsion for engine testing. The predicted optimal parameters were found as 20% water to diesel ratio, 0.9% surfactant and 2200 rpm of stirrer for a water separation of 14.33% in one day with a variation of 6.54% against the actual value of water separation. Water–diesel emulsion fuel exhibited similar fuel properties as base fuel. The peak cylinder gas pressure, peak pressure rise rate and peak heat release rate for water–diesel were found higher as compared to diesel at medium to full engine loads. The improved air-fuel mixing in water–diesel emulsion enhanced brake thermal efficiency (BTE) of engine. The absorption of heat by water droplets present in water–diesel emulsion led to reduced exhaust gas temperature (EGT). With water–diesel emulsion fuel, the mean carbon monoxide (CO), unburned hydrocarbon and oxides of nitrogen (NOx) emissions reduced by 8.80, 39.60, and 26.11%, respectively as compared to diesel.  相似文献   
104.
105.
水生态文明是生态文明的重要组成和基础保障,是实现生态文明的重要支撑.进行水生态文明建设的重要基础保障是法律,而法律保障中最基础的一个环节就是立法,因此通过立法来保障水生态文明建设成为必然的趋势.选取江苏这一地区,从地方法治的角度出发,分析江苏省水生态文明建设在立法取得的成果以及存在的应当注意的问题.在此基础上结合江苏省的特殊省情,从立法的重点内容、立法程序以及立法监督三个方面提出完善地方水生态文明立法的建议.  相似文献   
106.
刘体劲  吴迪 《环境工程》2016,34(9):148-151
随着我国经济的快速发展,伴随而来的是日趋严峻的环境污染,而在政府环境监管的背景下,各个利益相关者之间的博弈在环保效果实施中发挥了很大的作用。利用博弈论的分析方法,建立了一个关于中央政府、地方政府和企业三个利益相关者之间的利益博弈模型,通过对该模型的求解得出三方的平衡状态。最后针对如何实现政府高效监管和企业最优环境策略,向博弈三方共同努力推动社会经济可持续发展提供了相关政策建议。  相似文献   
107.
Given many potential obstacles, what types of strategic plans and measures for climate protection and/or energy sustainability are more likely than others to be adopted by cities? What are the key internal and external obstacles to adopting and implementing these plans and measures? Based on data obtained from a survey conducted from 2010 to 2011 and other sources, this paper develops a framework derived from political contracting theory and strategic orientation literature to examine how public management obstacles, socio-economic factors, and political factors influence a city's likelihood of having strategic energy sustainability plans and measures in place. Moreover, this paper finds that many California cities remain reluctant to require residents and businesses to comply with more challenging sustainability measures, such as smart-growth land-use practices, and that those cities with a strategic energy sustainability plan already in place tend to be more willing to adopt smart-growth land-use measures.  相似文献   
108.
Urban growth is a key issue for spatial planning as it influences urban patterns and disrupts open landscapes. To effectively steer urban growth towards compact urban forms, many growth-management policies have been developed over recent decades. However, few studies have assessed how municipal policy mixes have evolved over time. In our representative Swiss-wide survey, we evaluated the prevalence and the time of introduction of 18 policies. Our results indicate that large municipalities use a broad range of reinforcing policies over decades. In contrast, small municipalities mostly rely on conventional land-use regulations. The lack of innovative, incentive-based policies casts doubt on small municipalities' ability to effectively manage urban growth. However, our analyses reveal recent efforts by small municipalities to diversify approaches to growth management and adopt innovative policies. These efforts should be supported by guiding small municipalities in their policy choices, and providing support to those lacking planning capacity.  相似文献   
109.
ABSTRACT: Forces driving the initiation of watershed management activities in Alabama have ranged from top-down, agency-led initiatives to bottom-up, citizen-led initiatives. A number of watershed projects in Alabama were examined including three NPS projects funded by U.S. EPA grants and a more comprehensive locally-initiated watershed management authority. Watershed projects were categorized into four different models. Factors which produced significant differences in the development and utilization of social capital and local capacities for watershed management were investigated. The success of watershed management initiatives was examined qualitatively and appears to correlate with a number of social factors. These factors include the extent of stakeholder involvement, the availability of social capital in the watershed, and the presence of a real or perceived water resource concern or problem. Both short term project success and the longer term prognosis for continued watershed management activities seems to depend most upon the amount of social capital in the watershed. Two major changes in resource management programs and organizations could lead to increased focus on and support for local watershed management initiatives. These are reorganization of resource management agencies around watershed units, and assignment of at least one staff person in each watershed unit to watershed management.  相似文献   
110.
Wildlife conservation and management (WCM) practices have been historically drawn from a wide variety of academic fields, yet practitioners have been slow to engage with emerging conversations about animals as complex beings, whose individuality and sociality influence their relationships with humans. We propose an explicit acknowledgement of wild, nonhuman animals as active participants in WCM. We examined 190 studies of WCM interventions and outcomes to highlight 3 common assumptions that underpin many present approaches to WCM: animal behaviors are rigid and homogeneous; wildlife exhibit idealized wild behavior and prefer pristine habitats; and human–wildlife relationships are of marginal or secondary importance relative to nonhuman interactions. We found that these management interventions insufficiently considered animal learning, decision-making, individuality, sociality, and relationships with humans and led to unanticipated detrimental outcomes. To address these shortcomings, we synthesized theoretical advances in animal behavioral sciences, animal geographies, and animal legal theory that may help conservation professionals reconceptualize animals and their relationships with humans. Based on advances in these fields, we constructed the concept of animal agency, which we define as the ability of animals to actively influence conservation and management outcomes through their adaptive, context-specific, and complex behaviors that are predicated on their sentience, individuality, lived experiences, cognition, sociality, and cultures in ways that shape and reshape shared human–wildlife cultures, spaces, and histories. Conservation practices, such as compassionate conservation, convivial conservation, and ecological justice, incorporate facets of animal agency. Animal agency can be incorporated in conservation problem-solving by assessing the ways in which agency contributes to species’ survival and by encouraging more adaptive and collaborative decision-making among human and nonhuman stakeholders.  相似文献   
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