Mapping the agricultural land use of the North China Plain in 2002 and 2012

Journal of Geographical Sciences - Based on the MODIS NDVI data and Landsat TM/ETM data of 2002 and 2012, this paper extracts the planting area of winter wheat—summer maize, single spring...     

土地类型结构与农业综合自然区划的初步研究——以北京市为例

本文以北京市土地类型组合结构为依据,将北京市划分出三个区17个亚区,并就每一亚区的自然特征和合理利用方向进行了探讨。本文以北京市土地类型为例,研究土地类型结构并探索其为农业综合自然区划服务的途径。     

AN ANALYSIS ON THE STRUCTURE TYPES AND BENEFITS OF SLOPELAND AGROFORESTRY SYSTEMS-Taking the Three Gorge Reservoir Area As An Example

Chinahasalongltist0ryofaghcLIlturaldeveloPn1atn1edeveloPmatandLttilizahonofplanlsaremoreextensivethanthatofmotUAsinsandhills.Underthepressureofil11Promplivingstandardf0rl.2billionpeOPleatpresa1t,itistmdoubtedtoaCCeeratesl0PelanddeVeopmat.HOWdowerealizehig…     

我国地理教育研究热点年度盘点与前瞻——基于2020年《复印报刊资料·中学历史、地理教与学》转载地理教育论文的分析

通过对2020年《复印报刊资料·中学历史、地理教与学》全文转载地理教育论文的栏目分布情况、源杂志转载量和主要内容等方面进行分析,可看出近年我国地理教育研究热点包括国际地理教育进展、地理教科书的编写与历史、地理教学的设计与实施、地理教育测量与评价、地理教师发展等方面。未来地理教育研究需要关注高中地理选择性必修教科书的探讨、地理概念体系的构建、地理思维的培养、安全教育实施的途径、地理教学质量和教师专业发展的评价等方面。     

西北太平洋上层海洋对台风“巴威”(2008)的响应分析

基于多源卫星遥感数据、Argo浮标数据和HYCOM（HYbrid Coordinate Ocean Model）再分析数据,分析上层海洋对2020年第8号北上强台风“巴威”的温盐响应特征,结果表明：（1）台风中心附近埃克曼（Ekman）抽吸引起上升流,表层以下海水辐合高盐冷水上翻,Ekman输运方向由台风路径指向路径两侧沿岸,海水在黄海两侧沿岸堆积引起下降流。由此导致台风路径附近海面温度（sea surface temperature,SST）与海面高度（sea surface height,SSH）下降,海面盐度（sea surface salinity,SSS）上升,路径两侧沿岸SSH上升,次表层海水温度增加和盐度降低。（2）由于台风前进方向右侧的风速更大,右侧Ekman输运强度比左侧大。台风更靠近右侧陆地,地形阻挡导致风速减小,在济州岛西南侧的海域上空10 m风呈现反气旋旋转,出现负Ekman抽吸速率（Ekman pumping velocity,EPV）,为下降流,所以在台风和济州岛之间的海域存在着由强烈上升流到下降流的转变。这会让原本台风前进方向右侧强的夹卷和垂直混合进一步加强。这就导致了SST下降和SSS上升在台风前进方向右侧更为显著。（3）除了夹卷和垂直混合,台风前进方向右侧SSS的增加还与表层海水由南向北的水平流动有关。     

Public housing and migration: a multi-level modelling approach

"This paper...[analyzes] the distance moved by one-year migrants using a multi-level modelling approach. Controlling for a range of socio-economic variables, derived from the 1991 British Census Sample of Anonymised Records (SAR), at both the individual and area level, the distance moved by household heads in public, privately rented and owner-occupied housing within Britain is assessed.... It is confirmed that migrants in public housing are less likely to migrate long distances than owner-occupiers and that the proportion of public housing in a SAR area, and the absolute reduction in public housing in a SAR area between 1981 and 1991, does not have a significant effect on the distance that in-migrants have moved."     

Scientific and technological power and international cooperation in the field of natural hazards: a bibliometric analysis

Natural Hazards - Research on natural hazards has become a focus due to the serious threat to human life and property. Based on the Science Citation Index Expanded and the Social Sciences Citation...     

基于构造超压的地层压力预测方法研究

Traditional formation pressure prediction methods all are based on the formation undercompaction mechanism and the prediction results are obviously low when predicting abnormally high pressure caused by compressional structure overpressure. To eliminate this problem, we propose a new formation pressure prediction method considering compressional structure overpressure as the dominant factor causing abnormally high pressure. First, we establish a model for predicting maximum principal stress, this virtual maximum principal stress is calculated by a double stress field analysis. Then we predict the formation pressure by fitting the maximum principal stress with formation pressure. The real maximum principal stress can be determined by caculating the sum of the virtual maximum principal stresses. Practical application to real data from the A1 and A2 wells in the A gas field shows that this new method has higher accuracy than the traditional equivalent depth method.