Vulnerability Assessment Of High Temperature Disaster In Kiwifruit

The kiwifruit(Actinidia chinensis)has been cultivated in China for nearly a century and is loved and recognised for its sweet and sour taste and rich nutrition.Shaanxi province is the main kiwifruit producing region in China,and it is the largest in the country,both in terms of planted area and fruit production.In recent years,however,extreme heat events triggered by global warming have posed a great threat to the kiwifruit growing industry.It is therefore particularly important to actively carry out research on the evaluation of heat and heat damage risks to kiwifruit.Mitigation of agro-meteorological hazards should be based on both reducing the risk of contributing factors and reducing vulnerability to hazards.It is therefore an urgent task to measure the vulnerability of kiwifruit to heat damage,to analyse the causes of vulnerability,to identify ways of reducing vulnerability and to explore ways of preventing and resolving heat damage risks.The aim of this study was to evaluate the vulnerability of kiwifruit to high temperature heat damage in the study area.Firstly,30 indicators were selected from three perspectives:exposure,sensitivity and adaptability.Pearson correlation analysis and principal component analysis were used in turn to screen the evaluation indicators,and factor analysis was used to test their reasonableness.Subsequently,the weighting of each indicator was determined using a combination of assignment methods.The evaluation was carried out using the composite index method and the Kullback-Leibler(KL)distance-based improved TOPSIS model,respectively.Finally,the criterion and indicator layers were analysed using the obstacle model.The aim is to find the factors that have a greater impact on reducing the vulnerability of kiwifruit to high temperature heat damage in the study area,so that recommendations can be made for disaster prevention and mitigation according to local conditions.The main findings are as follows:(1)Pearson correlation analysis and principal component analysis were used to screen the primary selection indicators,and 13 evaluation indicators were retained.The rationality of the evaluation indicators was verified along the lines of factor analysis.The results found that43.33% of the indicators were retained in this study,reflecting 60.31% of the original information.The evaluation indicator system is rational.(2)The determination of the weighting of the evaluation indicators is carried out using the combination weighting method.Subjective weights are obtained by means of the sequential relationship analysis method(G1 method)and objective weights are obtained by means of the Critic method,which is based on an improved entropy weight method.By combining the extensive experience of the experts with the raw data information,a weighting factor with a high degree of accuracy was obtained.(3)Both the improved TOPSIS model and the composite index method show greater vulnerability to high temperature heat damage in northern and southern Shaanxi.The Guanzhong Plain has a low level of vulnerability and the area is favourable for kiwifruit cultivation.However,there were some differences in the results of the two evaluation models.To further verify the reliability of the evaluation results,the results were compared with the high temperature event data of Shaanxi Province from 1960 to 2020,and the results of the improved TOPSIS model were found to be more consistent with the historical disaster data.(4)The sensitivity indicators have a greater hindering effect on reducing the vulnerability of agricultural heat damage in Shaanxi Province through the barrier degree model analysis.We propose to upgrade agricultural technology production in the more exposed northern Shaanxi region.For the Guanzhong region,where adaptation is relatively weak,financial support for agriculture should be increased.Strengthen farmers’ awareness of disaster preparedness and enhance their ability to cope with disasters.The southern Shaanxi region as a whole is highly dependent on agricultural production and suffers greater losses in the event of a major natural disaster.The regional economy should be actively developed,the industrial structure should be changed and the proportion of the agricultural population,i.e.agricultural production,should be reduced.This study provides a theoretical basis for evaluating the vulnerability of kiwifruit to high-temperature heat damage,and the indicators can be applied to the vulnerability evaluation of other crops by combining their own characteristics,providing a reference for the Shaanxi Provincial Government on disaster prevention and mitigation measures and management.