• 研究报告 •

### 1962—2010年甘肃省黄土高原区干旱时空动态格局

1. (1西北师范大学地理与环境科学学院， 兰州 730070； 2甘肃农业大学林学院， 兰州 73007； 3忻州师范学院地理系，山西忻州 034000)
• 出版日期:2012-08-10 发布日期:2012-08-10

### Spatiotemporal pattern of drought in Loess Plateau of Gansu Province, Northwest China in 1961-2010.

ZHANG Tiao-feng1, ZHANG Bo1**， ZHANG Miao2, LIU Xiu-li1,3，SUN Li-wei1, AN Mei-ling1

1. (1School of Geography and Environment Science, Northwest Normal University, Lanzhou 730070, China; 2College of Forestry, Gansu Agricultural University, Lanzhou 730070, China; 3 Department of Geography, Xinzhou Teachers University, Xinzhou 034000, Shanxi, China)
• Online:2012-08-10 Published:2012-08-10

Abstract: Drought, one of the most severe hazards resulting in significant economic losses in agriculture and industry, is a natural phenomenon caused by the imbalance between the input of and the demand for water. As a major grain production zone in Gansu Province, the Loess Plateau of the Province shows great vulnerability in drought. In this paper, the characteristics of interannual and seasonal droughts in the Loess Plateau of Gansu Province were analyzed in terms of drought rate, drought intensity, and drought frequency, and by using the compound index of meteorological drought (CI) and the data of daily precipitation, air temperature, wind speed, relative humidity, and sunshine duration from 33 weather stations during the period from 1962 to 2010. Kriging interpolation was also applied to calculate the CI value for each station, so that all the CI values could be spatially and temporally comparable. In the Plateau of the Province, drought rate showed a significant increasing trend in spring and autumn but a slight increasing trend in summer and winter, and drought frequency was the most in summer, followed by in spring and autumn, and in winter. The 50-year average drought rate in spring, summer, autumn, and winter was 53.26%, 65.18%, 42.2%, and 44.16%, respectively. Over the past 50 years, the most serious inter-decadal drought in the Plateau of the Province occurred in spring and autumn since 2000, and in winter in the 1980s. In the 1970s and 1980s and since 2000, summer drought was more serious. There was a notable interannual fluctuation in the average annual lasting days and annual occurrence severity of meteorological droughts in the whole region, and their linear change tendency was obvious. Spatially, in spring, summer, and autumn, the droughtprone area was mainly located in the northwest of the region. Meanwhile, in the districts of “LintaoTongweiTianshui” and southeast of Qingyang, the change range was the largest. The droughtprone area in winter was mainly located in south of the region. In order to well prevent and mitigate the drought in the Loess Plateau of Gansu Province, government and agricultural managers should pay more attention to the droughts that occur from spring to autumn, especially in summer.