近50年陇东黄土高原干旱特征及未来变化趋势分析

发布时间：2018-04-29 07:02

本文选题：陇东黄土高原 + SPEI　；参考：《干旱地区农业研究》2017年02期

【摘要】：基于陇东黄土高原近50 a平均逐月降水和气温数据,以标准化降水蒸散发指数(SPEI)作为干旱评价指标,采用线性趋势方法、Mann-kendall突变分析法,小波分析法、R/S分析法,马尔科夫预测模型分析了陇东黄土高原近50 a来干旱变化周期特征及变化趋势,预测了未来干旱趋势和发生的概率。研究显示:近50 a陇东黄土高原SPEI线性倾向率小于0,整体呈干旱化趋势,陇东黄土高原干旱变化的突变点在1993年左右;通过小波分析,年际尺度的SPEI存在19、11、7、4、2 a的主周期,月尺度的SPEI存在17、25、35、10、6个月主周期;SPEI12的Hurst值0.640.5,自相关系数Rt0,在未来一段时间内干旱化趋势将会持续;通过Markov预测分析,干旱状态演变过程中干旱极端化现象的概率会增多,严重干旱状态的持续性将增强。
[Abstract]:Based on the average monthly precipitation and temperature data of the Loess Plateau in East Gansu Province in recent 50 years, the standardized precipitation evapotranspiration index (SPEI) is used as the drought evaluation index, and the linear trend method, Mann-kendall mutation analysis method and wavelet analysis method are used to analyze the drought. Markov prediction model analyzes the variation cycle and trend of drought in the Loess Plateau of East Gansu Province in the past 50 years and forecasts the future drought trend and occurrence probability. The results show that the linear tendency rate of SPEI in Longdong Loess Plateau is less than 0 in recent 50 years, and the whole trend is drought, the abrupt point of drought variation in Longdong Loess Plateau is about 1993, and the interannual SPEI has a main period of 19 / 117 / 4a by wavelet analysis. The Hurst value of SPEI12 is 0.640.5, the autocorrelation coefficient RT _ 0 is 0.64. 5, and the trend of drought will continue in the future. The probability of extreme drought phenomenon in the course of drought state evolution will increase by Markov prediction analysis, and the Hurst value of SPEI12 is 0.640.5, and the autocorrelation coefficient RT _ 0 of SPEI12 is 0.640.5, and the trend of drought will continue in the future. The persistence of severe drought will increase.
【作者单位】：陇东学院历史与地理学院;西北师范大学地理与环境科学学院;庆阳市荒漠化防治研究中心;
【基金】：国家自然科学基金项目(41561024,31460090) 高校博士学科点专项科研基金项目(20136203110002) 甘肃省高等学校科研项目(2016B-101) 陇东学院青年科技创新项目(XYSK1501,XYSK1601)
【分类号】：S423

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