基于SPI的渭北黄土高原干旱时空特征

发布时间：2018-03-29 14:45

本文选题：SPI　切入点：渭北黄土高原　出处：《生态环境学报》2016年03期

【摘要】：渭北黄土高原是陕西省重要的粮食生产基地,为了提高该地区应对干旱气候事件的能力,利用1986─2015年渭北黄土高原地区逐日降水资料详细分析该地区干旱变化的时空演变规律,通过计算标准化降水指数(SPI),定量表征该地区的干旱时空特征,结果表明:(1)近30年该地区SPI和降水量的变化趋势基本相近,都呈规律性波动变化,但有些月份差异比较大,这是由于SPI对不同时间尺度降水量的敏感性不同。(2)不同时间尺度的SPI可以较好地反映干旱洪涝的发展演变状况和趋势。SPI能够明确地反映渭北黄土高原的干旱变化状况,短时间尺度(1个月)能够反映逐月的干旱变化,3个月能够反映季节的干旱变化,而长时间尺度(12个月)则可以反映水分的滞后性作用。通过对多时间尺度SPI的时间序列分析可以发现,渭北黄土高原总体上有变湿的趋势,且随着时间尺度的增加,SPI的随机性在减弱,持续性在加强。与气候变化相对应,全区干旱频次有总体下降的趋势。(3)渭北黄土高原干旱主要出现在1993、1994、1997、1998和2001年。对不同季节的SPI分析结果表明,春季和夏季干旱发生频率较高,秋季和冬季干旱频率较低。同时,干季干旱频率较高,湿季干旱频率较低。(4)渭北黄土高原不同地区干旱具有相对一致的趋势。研究结果可为渭北黄土高原农业旱情管理与决策提供科学依据。
[Abstract]:Weibei Loess Plateau is an important grain production base in Shaanxi Province, in order to improve the ability to cope with drought events in the region, with the spatial-temporal evolution analysis of drought change in this area from 1986 to 2015 in Weibei Loess Plateau area daily precipitation data, by calculating the standardized precipitation index (SPI), spatio-temporal characteristics of drought in the region. Quantitative characterization results show that: (1) change trend in recent 30 years in the area of SPI and precipitation are basically similar, regular fluctuation change, but some months of relatively large differences, this is due to the sensitivity of SPI on different time scales of precipitation are different. (2) different time scales can reflect the development of SPI the drought flood evolution status and trend of.SPI can clearly reflect the drought conditions in Weibei Loess Plateau, short time scale (1 months) can reflect the drought changes from month to month, 3 months to reflect the season The change of drought, and long time scale (12 months) can reflect the water lag effect. The time series of the multi time scale analysis of SPI can be found in Weibei Loess Plateau on the whole a wetting trend, and with the increase of the time scale, the randomness of SPI reduction in the weak, persistent in strengthening. Corresponding to climate change, the drought frequency overall downward trend. (3) in Weibei Loess Plateau drought mainly occurred in 1993199419971998 and 2001. The SPI analysis results show that in different seasons, spring and summer drought occurred in high frequency, autumn and winter drought frequency is low. At the same time, the frequency of drought in dry season high wet season drought frequency is low. (4) drought in different regions of Weibei Loess Plateau has a relatively consistent trend. The research results can provide scientific basis for Weibei Loess Plateau agricultural drought management and decision.

【作者单位】：长安大学地球科学与资源学院;陕西省灾害监测与机理模拟重点实验室;中国科学院生态环境研究中心城市与区域国家生态重实验室;
【基金】：高分地球表层系统科学研究应用示范系统(一期)黄土高原生态系统变化研究示范(30-Y30B13-9003-14/16) 国家自然科学基金项目(41501091) 陕西省自然科学基金项目(2014JM5211) 陕西省教育厅重点实验室科研计划项目(14JS010)
【分类号】：S423

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