近45a达里诺尔湖面积演变对气候的响应

Response of Dali Lake area to climate factors in the past 45 years

以位于半干旱地区的达里诺尔湖为研究对象,利用地形图和1972-2016年Landsat遥感影像,通过人工目视解译方法提取达里诺尔湖水域面积,结合同期气温、降水、蒸发量资料,分析了达里诺尔湖水域面积时空变化及其对气候因子的响应。结果表明:近45年来,研究区年平均气温显著升高了1. 1℃,降水量减少了9. 0mm,蒸发量增加了208mm;达里诺尔湖水域面积从1972年的233. 15km^2下降到2016年的191. 43km^2,下降速率为8. 77km^2/10a;达里诺尔湖水域面积与年降水量和夏季降水量均呈极显著正相关(P <0. 01),相关系数分别为0. 696、0. 618,与年平均气温、年最高气温、年蒸发量、夏季蒸发量呈显著正相关(P <0. 05)。

Dali Lake which is located in the semi-arid region,was chosen as the research object. By using Landsat remote sensing image from 1972 to 2016,the area of the Dali Lake was extracted by artificial visual interpretation method. The temporal-spatial variations of lake area as well as its response to climate factors were comprehensively studied. The results showed that the annual average temperature in the study area had risen significantly by 1. 1℃,with a decrease of 9. 0 mm in precipitation and an increase of 208 mm in evaporation over the past 45 years. The lake area had been gradually shrinking from 233. 15 km^2 in 1972 to 191. 43 km^2 in 2016,and the decrease rate was 8. 77 km^2/10 a. There was a extremely significant positive correlation between the area of Dali Lake and annual precipitation and summer precipitation( P < 0. 01) with the simple correlation coefficients were 0. 696 and 0. 618,respectively. The annual average temperature and the annual highest temperature and annual evaporation and summer evaporation were positively significantly correlated with the area of Dali Lake( P< 0. 05).