农用地质量等级划分依据及其基本思路

农用地质量等级划分是国土资源大调查的主要内容。本文首先对农用地质量的实质内涵进行了探讨 ,提出衡量农用地综合质量高低的三要素 ,即土地适宜性、土地生产潜力和现实生产力 ;其次 ,运用土地肥力理论以及土地经济学的基本原理对农用地质量“等 -级”体系建立的客观基础及其划分的理论依据进行了分析 ;最后 。

基于GIS的安塞县县南沟流域农用地生态适宜性评价

利用立地条件、土壤性质和土地利用状况3个方面共8个因子构建县南沟流域农用地生态适宜性评价指标体系,采用AHP层次分析法和专家打分的方式确定各评价因子的权重,在遥感(RS)和地理信息系统(GIS)技术的支持下,利用适宜性评价模型定量评价流域农用地生态适宜性,将各土地利用类型适宜性划分为4个等级,结合各土地利用类型的重要程度与适宜性等级划分流域内农用地各区域的适宜性。结果表明:流域内宜耕宜园地面积为225.46hm^2,占流域总面积的5.09%;宜耕地面积为405.68hm^2,占9.17%;宜林宜园地面积为156.96hm^2,占3.55%;宜园地面积为773.15hm^2,占17.47%;宜林宜草地面积为881.43hm^2,占19.91%;宜林地面积为409.91hm^2,占9.26%;宜草地面积为1 490.00hm^2,占33.66%;不适宜和非生产用地面积为83.43hm^2,占1.89%。研究结果可为县南沟流域农用地的合理划分提供科学参考。

Basic Farmland Plan Based on Farmland Gradation

Taking B District in A City as an example, quality classification of basic farmland was evaluated based on farmland gradation. It can be concluded from the analysis that utilization grade of basic farmland in current round was 16.82 without consideration of farmland gradation updating, and the grade enhanced by 0.08, still lower by 0.11 than that in last round, when the updating was taken into account. Finally, the reasons for problems occurred in the round were analyzed as follows： less consideration of protection on basic farmland in orientation of urban development; neglecting of basic farmland quality in Overall Plan of Land Utilization; non-classification of excellent lands after land consolidation; untimely updating of farmland gradation. In addition, the countermeasures were proposed correpondingly, including strengthening of basic farmland quality in the Plan, classification of excellent lands after consolidation, timely updating and inclusion of farmland gradation into ＂one map＂ project.