气候变化背景下宁波市茶叶早春霜冻灾害风险评估

Estimation of early-spring frost damage for tea plants in Ningbo under the background of climate change

基于自然灾害风险理论,利用1971—2020年宁波市127个气象站气象观测资料和茶叶生产相关资料,分析了宁波市茶叶早春霜冻空间分布规律,并通过层次分析(Analytic Hierarchy Process,AHP)和专家经验相结合的方法,构建了宁波市茶叶早春霜冻风险因子集,通过加权指数求和的方法建立了宁波市茶叶早春霜冻风险模型,对早春霜冻灾害风险进行了综合和分年代的评估。结果表明,宁波市茶叶早春霜冻出现的年平均天数分布总体呈现西低东高的特征,霜冻年平均天数的范围在0.23~21.43 d;宁波市茶叶早春霜冻高风险区主要集中在余姚南部的四明山区域、宁海西部和宁海东北部的茶山区域,低风险区主要分布于宁波东部沿海地区;20世纪70—90年代宁波市茶叶早春霜冻低风险和较低风险区域基本呈增长趋势,中风险和较高风险区域呈减少趋势,高风险区域80年代最多、90年代次之、70年代最少,21世纪00—10年代,宁波市茶叶早春霜冻低风险和中风险区域呈减少趋势,较低风险、较高风险和高风险区域呈增长趋势。

Using the observational data of 127 meteorological stations in Ningbo from 1971 to 2020 and related data of tea production,this study analyzed the spatial distribution of early-spring frost damage on tea plants in Ningbo.Based on natural disaster risk theory,the early-spring frost risk factor set of tea plants in Ningbo was build up through the AHP(Analytic Hierarchy Process)and Expert Scoring method.By using the method of weighted index summation,we established the early-spring frost risk model,and this model was used to comprehensively assess the early-spring frost risk by years.The results showed that the annual average number of days of early-spring frost ranged from 0.23 to 21.43 days,and the distribution was characterized by low in the west and high in the east.The high-risk areas were mainly concentrated around the Siming Mountain in the south of Yuyao,the west of Ninghai and Chashan area in the northeast of Ninghai.The low-risk areas were mainly distributed in the eastern coastal area of Ningbo.From the 1970s to the 1990s,the area of low-risk and lower-risk areas basically showed an increasing trend,while the area of medium-risk and higher-risk areas showed a decreasing trend.The high-risk areas were the most in 1980s,followed by the 1990s and the least in the 1970s.The area of low-risk and medium-risk areas showed a decreasing trend,while the area of lower-risk,higher-risk and high-risk areas showed an increasing trend from the 2000s to 2010s.