摘要
黄土高原地区生态环境脆弱,干旱的发生严重影响该地区农业生产和经济发展。选用1970—2012年南小河沟流域的降雨资料,使用标准化降雨指数(SPI)对干旱进行描述。对该流域内年及季节尺度SPI序列进行Mann-Kendall检验,并对所建立的不同时间尺度的季节性交乘趋势模型进行验证。结果表明:流域内出现干旱的频率为48.84%,年际SPI变化剧烈,整体向干旱化方向发展。春季干旱有明显的分阶段特征;夏季干旱变化趋势不显著;除1975年以外,秋季干旱变化趋势也不显著;冬季的干旱程度变化比较稳定,主要集中在无旱和轻旱等级之间。季节性交乘趋势模型在年干旱以及秋、冬季干旱评估中效果良好,干旱等级预测合格率均达到71.43%,模型在对干旱等级的分析出现错估时,有向中旱水平辐射的强烈趋势。
The ecological environment is fragile in the Loess Plateau, and the occurrence of the drought can serious-ly affect the agricultural production and economic development in the region. The rainfall data of 1970-2012 years in the Nanxiaohegou basin were selected, and the drought level was described by the standardized precipitation index （ SPI） . Mann - Kendall test was performed on the annual and seasonal scale SPI sequence and the seasonal cross multiply trend model was used to verify the drought on annual and seasonal scale. The results are as follows： the frequency of drought in the basin was 48.84%, the annual variation of SPI was severe, and in a direction towards the development of drought. Spring drought had obvious stage characteristics, the degree of summer drought was not significant, the trend of drought in autumn was not significant except for the year of 1975 and the degree of drought in winter was relatively stable, mainly concentrated in the non-drought and light-drought levels. The seasonal cross multiply trend model had good effect in an-nual, autumn and winter drought assessment, the pass rate a ll reached 71.43% and i t also had a strong tendency to esti-mate the other drought level to the moderate level when a prediction error occured.
出处
《干旱地区农业研究》
CSCD
北大核心
2017年第5期288-294,共7页
Agricultural Research in the Arid Areas
基金
国家自然科学基金资助项目(41171034)
陕西省教育厅服务地方专项计划项目(2013JC18)
陕西省教育厅省级重点实验室科研计划项目(14JS059)
2016陕西省水利科技计划项目(2016slkj-11)
