10—11月海南省瓜菜苗期湿涝风险评估与区划

Assessment and Distribution of Waterlogging Damage Risks for Melons and Vegetables in Hainan Province from October to November

为了评估海南省冬种瓜菜苗期生长阶段容易遭受的湿涝灾害,基于1998—2011年海南省18个气象站气象资料、各市县西瓜、豇豆、辣椒、丝瓜4种冬种瓜菜产量及苗期湿涝灾情资料,以降水量、降水日数等因子建立主成分分析综合指标,通过灾情反演构建苗期湿涝致灾等级指标,结合孕灾、灾损和防灾能力进行瓜菜苗期湿涝灾害综合风险分析与区划。结果表明:瓜菜苗期湿涝危险性从西南至东北增加,轻度与重度湿涝风险概率分布趋势相反,苗期湿涝孕灾敏感性从中西部山区向沿海和平原地区增加,瓜菜苗期湿涝灾损风险和防灾能力分布存在差异,且不同瓜菜差异明显;4种瓜菜苗期湿涝综合风险总体分布趋势一致,从西南至东北地区风险等级加重,降水、地势、土地等因素综合导致东部和北部部分地区苗期湿涝的风险高。

Hainan,as an important agricultural zone for winter melons and vegetables in China,suffers from waterlogging,chilling and drought risks that threat production during its growth period.In order to offer guidance to reduce waterlogging damage and assure production,the theoretical framework of natural disaster risk system is implemented based on meteorological station observations from 1998 to 2011,the yield and planted area data,as well as waterlogging disaster data for melons and vegetables.A waterlogging level index system is constructed through comparing the hazard index with disaster based on the principal component analysis of four factors,i.e.,precipitation,rain days,continuous rain days and maximum continuous rain days.A comprehensive waterlogging risk index model for melons and vegetables is built integrating with hazard index,damage sensitivity index,damage loss index and damage prevention capability index.Results show that the waterlogging hazard index increases from southwest to northeast,the risk probability of different level hazard index are different in regions,and the distribution of high and low risk probability are of the opposite.Due to results of disaster hazard spatial pattern,it implicates that more attention should be paid to those high hazard regions.Considering waterlogging sensitivity is partly influenced by slope gradient,the damage index increases from the central mountain to the periphery.Among three disasters,waterlogging causes most yield reduction for paprika,watermelon and cowpea which are in conformity with their biological characteristic.Taking yield loss and production status as factors to represent damage vulnerability and prevention capability,waterlogging damage loss index and prevention capability index differ in different regions.The distribution of comprehensive waterlogging risk index for melons and vegetables is similar for four kinds of melons and vegetables,which increases from southwest to northeast induced by factors such as precipitation,terrain and soil.The distribution characteristic is conformed to the real waterlogging situation in Hainan Province.Results can provide useful information which contribute to a better understanding of disaster damage risk for melons and vegetables and help for the policy formation of agro-meteorological disaster risk management.