摘要
基于新型MOD16遥感数据集,在产品数据精度验证的基础上,利用GIS与RS技术统计分析关中地区2000—2012年间实际蒸散发(ET)时空演变特征及不同土地利用类型蒸散差异。结果表明:(1)MOD16-ET在关中地区数据精度良好,验证相对误差和相关系数分别为10.38%和0.69;(2)关中地区多年ET均值为520.05 mm·a-1,空间分布大致呈西南-东北递减的三级阶梯格局,四季ET空间分布与多年平均情况基本一致。(3)ET空间分布受地表覆盖类型影响显著,各地类蒸散强度排序依次为林地(623.67 mm·a-1)>草地(504.51 mm·a-1)>园地(460.86 mm·a-1)>农田(448.89 mm·a-1)>裸地(408.77 mm·a-1);(4)关中地区ET年际变化趋势以0.87 mm·a-1的速率增加,空间分布呈东部减小西部增加的趋势,其中春、夏季变化区域面积比例较大且以增加趋势为主,秋、冬季节绝大部分地区ET年际变化不甚明显。关中地区年内各月ET大致呈先升后降的变化趋势,且蒸散量主要集中于夏季。
Based on the new MOD16 remote sensing data sets and the precision validation ,statistically analyzed the sptio-temporal evolving characteristics and the difference of evapotranspiration （ET ） by various land using types in Guanzhong region during 2000—2012 with support of GIS and RS technology .The results showed that ：（1 ） MOD16-ET data has a good precision in Guanzhong region ,the validated relative error and correlation coefficient were 10 .38%and 0 .69 ,respectively ;（2 ） The average multi-years ET in Guanzhong Region was 520 .05 mm·a-1 ,the spatial distri-bution was showed the three step pattern as approximately decreasing from southwest to northeast .The ET spatial distribu-tion in four seasons was the basic consistent with the multi-year average situation .（3） The ET spatial distribution had a significant effect by the land cover types ,the sequence of ET intensity for each land cover type is forest （623 .67 mm· a-1 ） 〉 grassland （504 .51 mm·a^-1 ） 〉 garden （460 .86 mm·a^-1 ）〉 farmland （448 .89 mm·a^-1 ） 〉 bare land （408 .77 mm·a-1 ）;（4） The annual variation trend of ET in Guanzhong Region was increased at 0 .87 mm·a-1 ,the spatial distribution was showed a tendency of decreasing in east and increasing in west ,among them ,in spring and sum-mer seasons had a rather greater proportion for changing areas ,while in autumn and winter seasons ,most of Guanzhong Region has no obvious ET variation .The monthly ET roughly showed a change trend of increasing first then decreasing , also the annual ET was mainly concentrated in summer season .
出处
《干旱地区农业研究》
CSCD
北大核心
2015年第3期245-253,共9页
Agricultural Research in the Arid Areas
基金
国家自然科学基金(41171310)
