基于"门槛-供需"耦合视角的县域农村生活可达性评价          下载免费PDF全文

杨兆晨  刘耀林  罗璇  安睿  姜永祯 《农业工程学报》2022,38(11):279-288

在乡村振兴背景下，农村生活设施布局优化对乡村发展、农村居民幸福感提升具有重要意义。针对农村可达性研究中评价对象与视角单一等问题，考虑四类生活设施，采用"面向服务需求的等时线分析方法"与改进的"两步移动搜索法"，从"门槛"与"供需"角度分析高安市农村生活可达性的空间分布特征，进而提出一种基于耦合视角的可达性分区模式，并探讨农村生活可达性的驱动机制与优化路径。结果表明：1）从最低时间成本来看，农村学前教育、大病就医、物流快递、文体活动均存在较大障碍，城乡发展的不均衡现象显著。2）从供需关系来看，教育资源与人口形成相对平衡的区域供需关系。部分乡镇中心医疗设施供给高于城区，商业与文体的供给普遍具有明显的城镇偏向性。3）基于"门槛-供需"耦合视角的农村可达性分区将高安市按四类设施分为高门槛-低供给、高门槛-高供给、低门槛-低供给、低门槛-高供给四种可达区和不可达区。农村生活可达性受空间阻抗与供需关系的影响，可从空间关系调整、生活设施与道路建设、生活服务服务要素流动三方面进行优化。研究可为县域农村生活设施、农村居民点的布局优化提供借鉴和参考。  相似文献   

Modelling soil erosion and sediment yield at a catchment scale: the case of Masinga catchment,Kenya     

B. M. Mutua  A. Klik  W. Loiskandl 《Land Degradation \u0026amp; Development》2006,17(5):557-570

Development of improved soil erosion and sediment yield prediction technology is required to provide catchment stakeholders with the tools they need to evaluate the impact of various management strategies on soil loss and sediment yield in order to plan for the optimal use of the land. In this paper, a newly developed approach is presented to predict the sources of sediment reaching the stream network within Masinga, a large‐scale rural catchment in Kenya. The study applies the revised universal soil loss equation (RUSLE) and a developed hillslope sediment delivery distributed (HSDD) model embedded in a geographical information system (GIS). The HSDD model estimates the sediment delivery ratio (SDR) on a cell‐by‐cell basis using the concept of runoff travel time as a function of catchment characteristics. The model performance was verified by comparing predicted and measured plot runoff and sediment yield. The results show a fairly good relationship between predicted and measured sediment yield (R²=0·82). The predicted results show that the developed modelling approach can be used as a major tool to estimate spatial soil erosion and sediment yield at a catchment scale. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献