摘要
农业旱灾是对我国农业生产影响最大的灾害之一,不同区域的旱灾成灾过程有所差异,如何定量评价旱灾发生过程中承灾体对农业旱灾的适应能力,一直是旱灾研究中的重点和难点。基于投影寻踪评价模型(PPE),能够将高维数据投影到低维子空间里,并基于改进的遗传算法(RAGA)优化投影方向,最终实现多指标的农业旱灾适应能力分类以及等级评价。由"灾前规避风险-灾中降低风险-灾后转移风险"的不同成灾过程,并考虑农业生产、生活系统的差异,从而对我国西南典型雨养农业区进行系统性、过程性的农业旱灾适应性评价。以乡镇为评价单元,结果表明研究区域的整体适应能力是不断增强的,且存在一定的区域差异,其中中部坝区以及南部山区适应能力较强,北部山区相比较弱。模型计算结果基本与实地考察情况基本一致,最后对该地区的农业旱灾适应情况进行分析,并提出有效的适应措施和建议。
Agricultural drought is one of the disasters that have major impact on the agricuhural production of China. Due to different disaster-causing processes in different regions, it has been a major focus and difficulty in drought research as to how to make quantitative evaluation on the adaptability of disaster-bearing bodies to agricul- tural drought in the process of drought disaster. Based on Projection Pursuit Evaluation （PPE） model, which could project high-dimensional data onto low-dimensional subspace, and based on the optimized projecting direction of the improved genetic algorithm （RAGA）, classifications and classified evaluation on the multi-index agricultural drought adaptability are realized at last. According to the different disaster-causing process of Avoiding Risks before Disaster-Reducing Risks during Disaster-Shifting Risks after Disaster and taking into consideration the differences in agricultural production and living system, systematic and process-based evaluation on the agricultural drought a- daptability of some representative rain-fed agricultural regions in southwest China are made. Taking villages and towns as the evaluation unit, the study showed that the overall adaptability of the studied regions was improving with certain regional differences, among which the central dam area and southern mountain area took on relatively strong adaptability while the northern mountain area presented relatively weak adaptability. As the result calculated by the model is consistent with on-spot investigation, analysis on the agricultural drought adaptability of the regions is made finally and effective adaptability measures and suggestions are proposed.
出处
《灾害学》
CSCD
北大核心
2014年第2期102-108,共7页
Journal of Catastrophology
基金
国家自然科学基金资助(41001059)
关键词
农业旱灾
适应性评价
投影寻踪
云南省施甸县
agricultural drought hazard
adaptability assessment
projection pursuit
Shidian County of Yunnan
