改进的突变评价法在河南省农业干旱中的应用

发布时间：2019-05-09 09:19

【摘要】：随着全球气候的显著变化以及水资源需求日益增长,我国农业系统面临的旱灾风险也不断增加。因此,有必要加强农业旱灾风险研究,为我国农业干旱灾害的科学管理以及防灾减灾策略的制定提供理论基础。本文以河南省为研究对象,在综合分析自然灾害风险及农业旱灾风险的基础上,提出了一种基于突变理论的农业旱灾风险分析方法,并利用该方法对河南省农业旱灾风险进行分析、评估,取得了以下的成果及结论:(1)本文通过分析研究河南省的农业干旱特点,从致灾因子的危险性、承灾体的脆弱性和暴露性以及抗旱能力等方面,分析导致干旱的原因。梳理和剖析干旱、旱灾、农业旱灾风险等基本概念,形成对农业干旱灾害风险的基本认知。除了采用传统干旱风险分析方法进行研究外,还可以将农业干旱灾害还原到自然灾害系统范畴,运用自然灾害系统相关理论来对其进行研究。(2)根据自然灾害风险原理,分析形成农业干旱的四个方面:危险性、脆弱性、暴露性以及抗旱能力,并在此基础上,根据评价指标的选取原则并与河南省实际状况相结合,选择恰当合理的评价指标,构建河南省农业干旱指标评价体系。利用熵值法,确定各个评价指标的权重,并按重要性进行排列,构建河南省农业干旱风险评价模型。(3)根据突变理论,建立基于突变理论的综合评价模型,并通过调整初始综合值以及构建拟合函数的方法对常规的突变评价方法进行改进,从而提高综合评价值的分辨率水平,可以更加直观地区别评价值的等级与大小。(4)利用突变评价模型对河南省农业旱灾进行风险评价与分析,一方面,从致灾因子的危险性、承灾体的脆弱性和暴露性以及抗旱能力等方面进行评价分析;另一方面,从气候因素、农用物资、生产条件以及农田水利等方面对河南省的粮食产量进行评估,通过对各市粮食产量的分析进一步对河南省农业旱灾进行等级划分;最后,以河南省玉米种植为研究对象,把该区域玉米生育周期划分为以下四个阶段:第一阶段,播种-育苗(6月);第二阶段,拔节-抽穗(6-7月);第三阶段,抽穗-乳熟(7-8月);第四阶段,乳熟-收获(8-9月),每个阶段在从气压、气温、相对湿度以及降水等方面结合突变评价法进行计算,通过计算结果对河南省农业旱灾进行分析。
[Abstract]:With the remarkable change of global climate and the increasing demand for water resources, the risk of drought in China's agricultural system is increasing. Therefore, it is necessary to strengthen the study of agricultural drought risk so as to provide a theoretical basis for the scientific management of agricultural drought disasters and the formulation of disaster prevention and mitigation strategies in China. Based on the comprehensive analysis of natural disaster risk and agricultural drought risk in Henan province, this paper puts forward a method of agricultural drought risk analysis based on catastrophe theory. By using this method to analyze and evaluate the agricultural drought risk in Henan Province, the following results and conclusions are obtained: (1) the characteristics of agricultural drought in Henan Province are analyzed and studied in this paper, according to the risk of disaster-causing factors, the risk of agricultural drought in Henan Province is analyzed and evaluated. The causes of drought are analyzed in the aspects of vulnerability and exposure of disaster-bearing bodies and drought resistance ability. Combing and analyzing the basic concepts of drought, agricultural drought risk and so on, to form the basic cognition of agricultural drought disaster risk. In addition to using the traditional drought risk analysis method, agricultural drought disaster can be reduced to natural disaster system category and studied by the theory of natural disaster system. (2) according to the natural disaster risk principle, the agricultural drought disaster can be reduced to the natural disaster system category. (2) according to the natural disaster risk principle, Based on the analysis of the four aspects of agricultural drought: risk, vulnerability, exposure and drought resistance ability, according to the selection principle of evaluation index and combining with the actual situation of Henan Province, the appropriate and reasonable evaluation index is selected. To construct the evaluation system of agricultural drought index in Henan province. The entropy method is used to determine the weight of each evaluation index and arrange it according to the importance to construct the agricultural drought risk assessment model in Henan Province. (3) according to the catastrophe theory, the comprehensive evaluation model based on the catastrophe theory is established. The conventional catastrophe evaluation method is improved by adjusting the initial synthesis value and constructing the fitting function, so as to improve the resolution level of the comprehensive evaluation value. The grade and size of the evaluation value can be distinguished more intuitively. (4) the risk assessment and analysis of agricultural drought in Henan Province is carried out by using the catastrophe evaluation model. On the one hand, from the risk of the disaster-causing factors, The vulnerability, exposure and drought resistance of disaster-bearing bodies were evaluated and analyzed. On the other hand, the grain yield of Henan Province is evaluated from the aspects of climatic factors, agricultural materials, production conditions and farmland water conservancy, and the agricultural drought in Henan Province is further classified according to the analysis of grain output of each city. Finally, the growing cycle of maize in Henan Province was divided into the following four stages: the first stage, sowing-seedling (June), the second stage, jointing-heading (June-July), and the third stage (June-July), the second stage was jointing-heading (June-July). Stage III, heading-milking (July-August); The fourth stage, milk ripening-harvest (August-September), each stage in terms of air pressure, air temperature, relative humidity, precipitation and other aspects of the sudden change evaluation method to calculate, through the calculation results of agricultural drought analysis in Henan Province.
【学位授予单位】：华北水利水电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S423

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