淮河上游植被对气象干旱的响应
张 特1,2, 刘 冀1,2, 魏 榕1,2, 常文娟1,2, 董晓华1,2, 孙周亮1,2

(1.三峡大学 水利与环境学院, 湖北 宜昌 443002; 2.水资源安全保障湖北省协同创新中心, 武汉 430072)

淮河上游; 气象干旱; 植被响应; SPEI指数; VCI指数

Response of Vegetation to Meteorological Drought in Upper Huaihe River Basin
ZHANG Te1,2, LIU Ji1,2, WEI Rong1,2, CHANG Wenjuan1,2, DONG Xiaohua1,2, SUN Zhouliang1,2

(1.College of Hydraulic and Environment, China Three Gorges University, Yichang, Hubei 443000, China; 2.Hubei Collaborative Innovation Center for Water Resource Security, Wuhan 430072, China)

upper Huaihe River Basin; meteorological drought; response of vegetation; SPEI; VCI

备注

淮河流域是我国重要的农业基地之一,探究植被对气象干旱的响应规律有助于指导该地区的农业生产及生态保护。基于标准化降水蒸散指数(SPEI)和植被状态指数(VCI),采用线性趋势法探讨了淮河上游王家坝以上流域2000—2014年气象干旱及植被时空变化,并通过年最大相关系数(YRmax)和季最大相关系数(SRmax)分析了植被在年际和不同季节对气象干旱的响应特征。结果 表明:(1)研究区SPEI整体以-0.089/a速率呈非显著干旱化趋势,淮河以北地区干旱化趋势相对明显;(2)研究区VCI整体以0.053/a速率呈显著上升趋势,整体植被状况逐渐好转,VCI显著下降的区域多分布于城镇附近;(3)年际上,78.4%的区域内VCI与SPEI显著相关,不同植被受气象干旱影响程度和敏感性整体差异不大;(4)春季和冬季植被受气象干旱影响的面积较广,分别有68.9%和64.8%的区域内VCI与SPEI显著相关,分布于流域西南、南部、北部和东部。夏季和秋季分别有31.3%和15.0%的区域内VCI与SPEI显著相关,夏季集中分布于流域中部,而秋季分布则比较零散;(5)春季和冬季不同植被的SRmax整体差异较小,春季冬小麦和草地对气象干旱比较敏感,而冬季各类植被的敏感性差异不大。夏季和秋季各类植被的SRmax整体上存在一定差异,但均未表现出显著相关性,植被普遍对4个月以下尺度的气象干旱敏感。2000—2014年淮河上游地区植被对气象干旱响应特征的空间差异性较大,研究结果可为变化环境下的农业生产和生态保护政策制定提供理论支撑。

Huaihe River Basin is one of the major agricultural bases in China. Exploring the response of vegetation to meteorological drought has guide significance for agricultural production and ecological protection in Huaihe River Basin. Based on the Standardized Precipitation Evapotranspiration Index(SPEI)and Vegetation Condition Index(VCI), the spatial-temporal variation characteristics of meteorological drought and vegetation in the area above Wangjiaba in upper Huaihe River Basin from 2000 to 2014 were discussed by liner trend, the responses of vegetation to meteorological drought in interannual and different seasons were also analyzed by annual maximum correlation coefficient(YRmax)and seasonal maximum correlation coefficient(SRmax). The result show that:(1)SPEI of study area presented a non-significant declining trend by the interannual change rate of -0.089/year, and the relatively significant decline area was the north of Huaihe River;(2)VCI of study area showed a significant increasing trend by the interannual change rate of 0.053 a, and the significant decline area concentrated in the vicinity of town;(3)on the interannual scale, there was 78.4% area where VCI was significantly correlated with SPEI, and there was no significant difference in impact and sensitivity of different vegetation to meteorological drought;(4)the area where the vegetation growth was more affected by meteorological drought in spring and winter was relatively larger, VCI and SPEI were significantly correlated in 68.9% and 64.8% of the whole area, these regions distributed in the southwest, south, north and east of the basin, respectively; there were 3 VCI were significantly correlated with SPEI in 31.3% and 15.0% of area in summer and autumn, respectively; in summer, the distribution concentrated in the middle of basin, but it scattered in autumn;(5)in spring and winter, the divergence of SRmax among different vegetation was small; wheat and grass were more sensitive to meteorological drought in spring, but the sensitivities of different types of vegetation were not significant in winter; the SRmax of various vegetation showed some differences in summer and autumn without significant correlation, and vegetation was generally sensitive to meteorological at the scale of less than 4 months. The response characteristics of vegetation to meteorological drought in the upper Huaihe River Basin had large difference in space from 2000 to 2014, these research results can provide theoretical support for formulating policy of agricultural production and ecological protection in the changing environment.