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河北省耕地生态安全及空间聚集格局 被引量:79
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作者 王千 金晓斌 周寅康 《农业工程学报》 EI CAS CSCD 北大核心 2011年第8期338-344,共7页
为了科学评判耕地生态安全态势与空间聚集格局。基于地理学研究中的空间格局分析技术,在压力-状态-响应框架下,结合生态学中的能值理论,构建县级耕地生态安全评价指标体系,估算河北省138个县耕地生态安全状况,重点探讨其空间聚集格局差... 为了科学评判耕地生态安全态势与空间聚集格局。基于地理学研究中的空间格局分析技术,在压力-状态-响应框架下,结合生态学中的能值理论,构建县级耕地生态安全评价指标体系,估算河北省138个县耕地生态安全状况,重点探讨其空间聚集格局差异特征,分析聚集格局产生的主要影响因素。研究结果表明:河北省138个县的耕地生态安全状况呈空间聚集分布格局,空间聚集度Moran'sI值为0.630;省域范围内存在2个聚集区,高值聚集区由石家庄、邢台以及邯郸组成,共23个县,耕地生态安全综合指数平均值为0.377,低值聚集区由张家口和承德大部组成,共22个县,耕地生态安全综合指数平均值为0.169,其他县市呈零散分布;高值聚集区内各县Theil指数大于低值聚集区;宏观角度上的地形地貌、降雨、土壤、耕地质量等因素是空间聚集格局分布与差异的主要动因。耕地生态安全评价与空间聚集格局特征分析为科学划定区域生态安全功能区,保障区域粮食安全生产提供科学依据。 展开更多
关键词 生态 模型 降雨 耕地生态安全 能值理论 压力-状态-响应模型 空间聚集格局 河北省
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基于能值分析的甘肃省耕地可持续利用时空分异研究 被引量:6
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作者 倪广亚 刘学录 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2015年第2期149-158,共10页
【目的】研究甘肃省耕地可持续利用的时间变化规律和空间分异特征,为甘肃土地利用总体规划及区域可持续发展提供决策依据。【方法】利用2005-2011年甘肃省及县(区)土地利用变更资料和社会经济资料,采用能值分析方法,在构建耕地可持续利... 【目的】研究甘肃省耕地可持续利用的时间变化规律和空间分异特征,为甘肃土地利用总体规划及区域可持续发展提供决策依据。【方法】利用2005-2011年甘肃省及县(区)土地利用变更资料和社会经济资料,采用能值分析方法,在构建耕地可持续利用评价指标体系基础上,对2005-2010年甘肃省以及2010年甘肃省各县(区)的耕地生态经济系统进行可持续利用评价;在Geoda和Arcgis软件支持下,对甘肃省各县(区)耕地可持续利用综合指数空间格局进行分析,对耕地利用分区,探讨耕地可持续利用的空间分异特征。【结果】2005-2010年甘肃省耕地可持续利用呈波动性发展,其中生产稳定性指数、经济可行性指数、社会接受性指数总体提高,但生态合理性指数总体降低。2010年甘肃省各县(区)耕地可持续利用综合指数总体较低,且县(区)耕地可持续利用综合指数差异明显,将甘肃省划分为河西区、陇东区、陇南区、甘南区、陇西区5个耕地利用区,耕地可持续利用综合指数依次降低。【结论】时间和空间变化特征都说明甘肃省耕地的可持续利用主要受生态合理性限制,为提高耕地可持续利用,必须提高耕地自身质量等级,改善耕地外部环境,促进耕地生态经济系统由能值密集型向能值安全高效型转变。 展开更多
关键词 可持续利用评价 能值分析 空间聚集格局 时序研究 耕地 甘肃省
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Spatial pattern of dominant tree species of the secondary monsoon rain forest in Lianjiang, Guangdong Province
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作者 韩维栋 高秀梅 +1 位作者 李林锋 卢昌义 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期101-104,146-147,共4页
Based on the summed dominance ratios of species in sample plots, the first three dominant species (Litchi chinensis, Elaeocarpus sylvestris and Canarium album) of the secondary monsoon rain forest of Mt. Royal Shoe in... Based on the summed dominance ratios of species in sample plots, the first three dominant species (Litchi chinensis, Elaeocarpus sylvestris and Canarium album) of the secondary monsoon rain forest of Mt. Royal Shoe in Lianjiang City, western Guangdong, were chosen for analyzing their spatial distribution pattern with the analysis methods such as frequency models of Poisson Distribution, Two Negative Items Distribution, Neyman Distribution, aggregate indexes, Taylor exponential equation and Iwao’s equation modeling. The results showed that these three species distributed in the congregate spatial pattern. Litchi chinensis and Elaeocarpus sylvestris had the characteristic of basic congregate population and attractive characteristic between their plants. The patterns for Canarium album may change and become more evenly distributed with the increase of density. The overall species spatial pattern also depended on the conservation of the secondary monsoon rain forest besides it was affected by the species reproduction characteristics and its growing environment. The congregate spatial patterns of three dominant species showed that it is important to conserve forest urgent conservation of the forest. 展开更多
关键词 Secondary monsoon rain forest Spatial pattern Summed dominance ratio Aggregate index
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Spatial-temporal Pattern Evolution of Manufacturing Geographical Agglomeration and Influencing Factors of Old Industrial Base:A Case of Jilin Province,China 被引量:6
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作者 LI Linshan MA Yanji 《Chinese Geographical Science》 SCIE CSCD 2015年第4期486-497,共12页
The primary object of this paper is to examine the spatial-temporal pattern evolution of manufacturing geographical agglomeration of the old industrial base.Industrial spatial agglomeration index and concentration rat... The primary object of this paper is to examine the spatial-temporal pattern evolution of manufacturing geographical agglomeration of the old industrial base.Industrial spatial agglomeration index and concentration ratio are used in this paper.Multiple linear regression models are also applied to try to explore the internal driving mechanisms on manufacturing geographical agglomeration.The results show that:1) the manufacturing agglomeration degree of Jilin Province is increasing gradually.The spatial polarization structure is visible;and the central region is the agglomeration area,in addition,the manufacturing industries of Changchun Proper present a trend of dispersion;2) the structure of manufacturing industries has changed,and the concentration ratio of labor-intensive manufacturing industry is declining,while the proportions of technology-intensive and capital-intensive manufacturing industry are relatively rising;3) marketing level,location accessibility,labor resources,capital,science and technology innovation capability,scale economy and the level of globalization affect manufacturing agglomeration with different degree.There are significant differences of the effects about employment,technology,the quality of residents and the export-oriented market on the industrial concentration ratio;4) in the future,the impact of policy and institution,export-oriented market and quality of resident on manufacturing geographical agglomeration pattern will be more profound. 展开更多
关键词 old industrial base manufacturing geographical agglomeration industrial spatial agglomeration index concentration ratio Jilin Province China
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