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Boundary Shift of Potential Suitable Agricultural Area in Farming-grazing Transitional Zone in Northeastern China under Background of Climate Change During 20th Century 被引量:3
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作者 YE Yu FANG Xiuqi 《Chinese Geographical Science》 SCIE CSCD 2013年第6期655-665,共11页
Climate change affected the agricultural expansion and the formation of farming-grazing transitional patterns during historical periods. This study analyzed the possible range of the boundary shift of the potential su... Climate change affected the agricultural expansion and the formation of farming-grazing transitional patterns during historical periods. This study analyzed the possible range of the boundary shift of the potential suitable agriculture area in the farming-grazing transitional zone in the northeastern China during the 20th century. Based on modem weather data, 1 km-resolution land cover data, historical climatic time series, and estimation by using similar historical climatic scenes, the following was concluded: 1) The climate conditions of suitable agriculture areas in the farming-grazing transitional zone in the northeastern China between 1971 and 2000 required an average annual temperature above 1℃ or ≥ 0℃ accumulated temperature above 2500℃-2700℃, and annual precipitation above 350 mm. 2) The northern boundary of the potential suitable agriculture area during the relatively warmer period of 1890-1910 was approximately located at the position of the 1961-2000 area. The northern boundary shifted back to the south by 75 km on average during the colder period of the earlier 20th century, whereas during the modem warm period of the 1990s, the area shifted north by 100 km on average. 3) The western and eastern boundaries of the suitable agricul^re area during the heaviest drought periods between 1920s and 1930s had shifted northeast by 250 km and 125 km, respectively, contrasting to the boundaries of 1951-2008. For the wettest period, that is, the 1890s to the 1910s, the shift of western and eastern boundaries was to the southwest by 125 km and 200 km, respectively, compared with that in the 1951-2008 period. This study serves as a reference for identifying a climatically sensitive area and planning future land use and agricultural production in the study area. 展开更多
关键词 land cover changes farming-grazing transitional zone climate change agricultural production
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湿地定义研究中的若干理论问题 被引量:26
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作者 殷书柏 吕宪国 武海涛 《湿地科学》 CSCD 2010年第2期182-188,共7页
针对目前还没有统一湿地定义研究现状,从逻辑学、系统论和自然地理学的相关原理出发,对湿地定义的内涵与外延、湿地定义多样性的原因、"公约定义"与"学科定义"的关系、湿地边界界定的指标及阈值确定等若干理论问题... 针对目前还没有统一湿地定义研究现状,从逻辑学、系统论和自然地理学的相关原理出发,对湿地定义的内涵与外延、湿地定义多样性的原因、"公约定义"与"学科定义"的关系、湿地边界界定的指标及阈值确定等若干理论问题进行了较透彻的理论分析。认为:湿地"学科定义"与"公约定义"之间不存在广义与狭义的关系,"公约定义"也不是湿地的管理定义;湿地定义多样性原因主要表现为将湿地定义为区域的类型、相同的内涵用不同语词表达以及把湿地边界标准纳入湿地定义之中等;将"学科定义"的湿地和与其邻近陆地和水体当作一个执行一定功能的整体,从自然区划角度看应命名为"湿地区",分布于"湿地区"中的植被和土壤并不都是湿地土壤和植被;利用具有随机性指标作为边界指标时,应以多年平均值作为边界标准,利用具有相对不变性土壤指标确定湿地边界,应将边界界定在急变处。 展开更多
关键词 湿地定义 内涵与外延 过渡带与过渡性 湿地区 边界界定
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中国农牧交错带界定的现状及进展 被引量:29
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作者 张建春 储少林 陈全功 《草业科学》 CAS CSCD 2008年第3期78-84,共7页
农牧交错带作为农业种植区与草原牧区的交汇地带,是一个十分敏感的区域,也是我国生态环境的一条过渡带和生态安全的重要屏障。在前人的研究基础上阐述了农牧交错带的概念及空间界定的研究进展和最新的研究成果,提出了农牧交错带界定中... 农牧交错带作为农业种植区与草原牧区的交汇地带,是一个十分敏感的区域,也是我国生态环境的一条过渡带和生态安全的重要屏障。在前人的研究基础上阐述了农牧交错带的概念及空间界定的研究进展和最新的研究成果,提出了农牧交错带界定中存在的问题,并展望了今后农牧交错带界定的前景。 展开更多
关键词 农牧交错带 界定 研究进展
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