期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
论明代著名政治家徐阶——兼与张居正比较 被引量:5
1
作者 谭平 《成都大学学报(社会科学版)》 2001年第4期37-40,69,共5页
本文对徐阶一生的功过作条分缕析 ,以纠正大多数相关著述中对徐阶的不公正评价 ,并论述了不公正评价徐阶的原因 ;通过与张居正的比较 ,证明他们都是优秀的政治家并互有短长 ,都应该予以充分肯定。
关键词 徐阶 海瑞 张居正 明代 政治家 评价 历史功绩 历史过错 历史地位
下载PDF
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
2
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
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部