瓦房店地区近50年水资源趋势分析

Trend Analysis of Water Resources of Wafangdian Area in Recent 50 Years

为了瓦房店地区农业经济发展和粮食生产的需要,为防灾减灾提供科学依据,研究在气候变暖环境下水资源变化趋势具有重要意义。使用大连瓦房店1961—2010年的月平均气温、降水量序列资料,用高桥浩一郎陆面蒸发经验公式估算蒸发量;采用Mann-Kendall秩次相关检验法、线性趋势等统计方法,分析了降水量、蒸发量和降蒸差水资源变化特征。结果显示:降水量、蒸发量和降蒸差年变化趋势呈一致性,其中1月最小,7月最大。夏季水资源丰富,秋季次之,春季和冬季最少。农作物生长季降水量、降蒸差近50年呈减少趋势,蒸发量变化平稳,气候倾向率分别为-6.588 mm/10 a、-7.684 mm/10 a和1.096 mm/10 a。年降水量、年降蒸差呈减少趋势,年蒸发量变化趋近于0,气候倾向率分别为-9.537 mm/10 a,-8.741 mm/10 a和-0.796 mm/10 a。年降蒸差缩小,极比达13.1,说明水资源在减少的同时,干旱、洪涝频率增加,提醒人们应注意水资源变化,做好农业结构调整。

It was very critical to make researches on the changes in water resources under the background of climate warming,in order to provide a scientific basis for the disaster prevention and mitigation,thus to promote the development of agricultural economy and food production in the region.The author estimated the evaporation with the empirical fomula of land evaporation by Koichiro Takahashi,using the monthly average temperature,precipitation sequence of data of Wafangdian,Dalian City from 1961 to 2010,and analyzed the charateristics of water resources change on precipitation,evaporation and the difference between precipitation and evaporation,using Mann-Kendall rank correlation test method,linear trend and other statistical methods.The result showed that the annual change of precipitation,evaporation and the difference between precipitation and evaporation trended to be consistent,among which,January was the minimum,July was the maximum.There were richest water resources in summer,richer in autumn and least rich in spring and winter.In crop growth season,precipitation as well as the difference between precipitation and evaporation approximate to 50 years trend to decrease.The change of evaporation was stable.Climate tendency rates were 6.588 mm/10 a,-7.684 mm/10 a and 1.096 mm/10 a,respectively.The annual precipitation as well as annual difference between precipitation and evaporation trended to decrease.The change of annual evaporation trended to be zero.Climate tendency rates were-9.537 mm/10 a,-8.741 mm/10 a and-0.796 mm/10 a,respectively.The annual difference between precipitation and evaporation reduced,with ultimate ratio reaching 13：1 which illustrated that in the meanwhile the water resources reduced,drought and flood frequency increased,reminding people of paying attention to the change of water resources and adjusting the agricultural structure accordingly.