中国交通运输碳排放及影响因素时空差异分析

为减少交通运输二氧化碳排放量,采用ESDA方法对交通运输碳排放时空分布格局进行研究,同时考虑了空间联系作用,构建GWR模型对碳排放影响因素进行时空差异分析.研究发现:(1)2000—2013年中国省域交通碳排放空间聚类特征随时间变化不大,存在显著的高值、低值聚类特征.京津冀地区、辽宁、山东、山西、陕西、河南地区为高值聚类区,新疆、青海地区一直处于低值聚类区.(2)碳排放影响因素在相邻地区差异较小.其中城镇化率、交通运输结构为主要推动因素,能源强度则起到关键抑制作用.应对碳排放聚类区域施行协同减排目标,同时,应根据因素影响作用差异,分区域制定针对性减排政策.     

资源型城市转型效率时空格局及影响因素探析：以陕甘宁能源富集区为例

基于数据包络分析、标准差椭圆和地理探测器方法，引入产业多样化指数和产业专业化指数，综合探讨陕甘宁资源型城市的转型效率、时空格局及其影响因素，得到2011—2020年陕甘宁资源型城市转型绩效综合得分及分布、不同发展阶段资源型城市转型绩效以及三省区各自资源型城市的转型绩效。结果表明：（1）2011—2020年陕甘宁资源型城市转型效率具有显著的时间和空间差异。（2）研究期内陕甘宁资源型城市转型效率空间分布格局基本保持稳定，仍以东西方向为主导。（3）地方财政一般预算内支出、城市建设用地面积、地区生产总值是影响资源型城市转型效率空间分异的主导因子。揭示了研究区资源型城市转型效率的发展演变态势及驱动因素，可为其持续优化转型提供决策依据。     

水湿生经济植物开发及涝渍地农业模式研究

简要阐述了利用水生和湿生植物开发涝渍地的必要性，报导了四湖地区涝渍地进行水生和湿生经济植物引种栽培和优化农业模式试验方面的研究结果，还讨论了在平原湖区涝渍地水湿生经济作物优化农业模式的优越性和生态效益。     

秦淮河流域城镇用地增长格局及其演化机制

利用四期遥感TM数据和GIS技术，通过分析20年秦淮河流域城镇用地增长格局及其演化机制，为流域综合管理和模拟提供重要参数，研究结果表明：①城镇用地增长显示阶段性和空间的不均匀性，增长拐点发生在1994年和2000年，空间上表现出增长“热极”与“热带”；②城镇用地增长阶段性是经济社会过程及驱动因子演化阶段的反映，回归分析显示城镇用地增长与城镇人口、经济总量及开发区发展相关系数高，这归于1992年开发区创建、投资增加与2000年撤县设区驱动的结果；③城镇用地增长格局变化是社会经济物质载体演化的体现，1992年后开发区成为城镇用地增长首要来源，2000年后东山新市区与大学城成为其增长核心和新形式，机场与高速公路网强化对城镇用地的空间导向。研究结果较客观地刻画了城市化格局与过程的演化规律，参数应用与数据精度的提高是今后研究的重点.     

OPTIMUM CROPPING AND GROUND WATER MANAGEMENT1

ABSTRACT: A decision model for optimum cropping pattern and ground water manaement alternatives in canal irrigated areas is pre sented. Various ground water management alternatives in conjunction with optimum cropping pattern and based on water production functions are compared. The model developed also ensures optimum utilization of surface and poor quality ground water and proper soil conditions for plant growth.     

The Urbanization Pattern of China in the 21st Century

Abstract

This paper begins by analysing the mutual influence between international trade and the environment, and then proceeds to explore the environment and trade conflicts. On the basis of sustainable development theories and the above discussion, the article suggests taking sustainable trade as a solution to the existing conflicts. This paper aims to find the way to strike a balance between international trade and environment based on the present situation in China.     

Waterfowls habitat modeling: Simulation of nest site selection for the migratory Little Tern (Sterna albifrons) in the Nakdong estuary

This paper aims to find patterns in nest site selection by Little Terns Sterna albifrons, in the Nakdong estuary in South Korea. This estuary is important waterfowl stopover and breeding habitat, located in the middle of the East Asia-Australasian Flyway. The Little Tern is a common species easily observed near the seashore but their number is gradually declining around the world. We investigated their nests and eggs on a barrier islet in the Nakdong estuary during the breeding season (May to June, 2007), and a pattern for the nest site selection was identified using genetic programming (GP). The GP generated a predictive rule-set model for the number of Little Tern nests (training: R² = 0.48 and test: 0.46). The physical features of average elevation, variation of elevation, plant coverage, and average plant height were estimated to determine the influence on nest numbers for Little Tern. A series of sensitivity analyses stressed that mean elevation and vegetation played an important role in nest distribution for Little Tern. The influence of these two variables could be maximized when elevation changed moderately within the sampled quadrats. The study results are regarded as a good example of applying GP to vertebrate distribution patterning and prediction with several important advantages compared to conventional modeling techniques, and can help establish a management or restoration strategy for the species.     

Do biodiversity indices behave as expected from traits of constituent species in simulated scenarios?

It is believed that diversity of plant communities has a positive effect on their productivity. The benefits of diversity are described by “biodiversity indices”, comparing yield of mixtures with yields of monocultures of constituent species. These indices are supposed to capture also the main mechanisms leading to increased yield. We have constructed a spatially explicit individual based model, simulating even-aged stand development, and compared the behaviour of selected biodiversity indices (overyielding, selectivity and complementarity) with expectations based on life history traits of constituent species. The results are based on comparisons of two species mixtures with corresponding monocultures. We designed three scenarios of changes in the two species life history differentiation, and compared the behaviour of the indices with expectation based on it. In the first scenario, selectivity was driven by increasing size inequality of the two species, mostly in accordance with expectations. The second scenario presents increasing shade tolerance of the smaller species that increased complementarity, again mostly as expected. In the last scenario, shortening of length of stress tolerance of the weaker species surprisingly increased values of the biodiversity indices. For each setting, we varied sowing density and spatial pattern of the constituent species. The behaviour of the indices was influenced by both factors, but the effect of density was more pronounced. In particular, at high sowing densities, the most important interactions happened in the very early stages of mixture development, and the behaviour of the indices was often counter-intuitive.     

江西省公路网规划对景观格局的影响分析

公路网作为廊道网络,对于景观格局的破碎化影响巨大.景观格局的破碎化会缩小景观斑块的尺寸,增加斑块之间的分离度,提高外界对斑块的干扰机率,最终导致生态系统生物多样性的降低,危害生态安全.提出了基于GIS的公路网景观格局影响分析的叠图法,并将其应用到江西省公路网规划环境影响评价中.该方法包括绘制景观图件、景观分类、景观指数计算以及景观影响分析4个步骤.     

基于复杂网络理论的原油贸易空间格局差异分析

本文采用复杂网络分析方法,结合区域分析与相似性分析,比较了十大进口国(地区)原油贸易空间结构差异.复杂网络分析旨在以入度、权重及结构熵勾勒出十大原油进口国(地区)石油贸易的拓扑结构差异,并在拓扑结构分析中结合区域分析以揭示十大贸易国(地区)原油进口贸易空间格局构成之不同;相似性分析则是在拓扑结构和空间结构研究基础上,进一步量化了十大进口国(地区)的空间结构差异程度及区位在进口国(地区)原油贸易空间格局形成中的作用.研究表明,主要进口国与地区的原油进口贸易空间结构存在显著差异.而地理区位差异越大的国家与地区间,贸易空间结构差异越大.除中国外,各原油进口大国与地区更倾向于选择较经济的进口地域;显著的多元化与均质化则导致了中国贸易空间格局的不经济.研究结果提示我们,多元化不应以过多牺牲经济性为前提,中国应权衡所面临的客观环境选择适合区域合作伙伴,才能更好的落实多元化进口策略,切实解决可能面临的石油安全问题.