摘要
基于农作物种植结构准确估算绿洲农田蒸散发,对中国西北干旱区水土资源优化配置和生态环境可持续发展有重要意义。利用1960-2010年县级农业统计数据和基于遥感提取的绿洲耕地分布数据,产生逐年的新疆绿洲三种农作物(棉花、小麦、玉米)种植比例时空分布数据集,并在此基础上利用Penman-Monteith单作物系数法估算农作物蒸散发。结果表明:1960-2010年全疆绿洲耕地面积持续增加,粮食作物占优势的单一种植结构类型已被经济作物替代,形成南疆棉花快速增加、北疆小麦快速减少的种植格局。近50年全疆三种农作物总蒸散发量增加了47.85%,棉花贡献率最高,其次为玉米,小麦最低。耕地面积和结构变化对绿洲农作物蒸散发时空分布和组成结构变化具有重要影响。
Evapotranspiration（ET） is an important process in the hydrological cycle of croplands in dry areas. Recently, significant cropland expansion and changes in crop planting patterns due to intensive human activity have influenced the water budget in arid areas of Northwest China. Accurate ET estimation is fundamental to water management and allocation.Up to now, a number of studies have concentrated on estimating ET by measurements, water balance, empirical approaches, and remote sensing models. However, they did not consider the effects of long-term changes in cropland area or planting pattern on agricultural water consumption. The spatial datasets of planting pattern including wheat, maize and cotton in Xinjiang from 1960 to 2010, were established by integrating agricultural statistics at the countylevel and cropland area maps extracted from LULC product. Thereafter, the actual ET of croplands was estimated using the FAO Penman-Monteith（P-M） equation, and the total ET（TET） of each watershed was calculated using the GIS technique. The results showed that（1）the cropland areas continued to increase and increased by a total of 90.9%. Since the 2000s,cash crop（cotton） has come to supplant staple crops（wheat and maize） in the planting structure of oasis cropland. From 1960 to 2010, about 72.2% of watersheds showed increasing trends of cotton planting, while 77.8% and 55.6% of basins experienced decreasing trends of wheat and maize planting. Results also showed that cotton planting proportions quickly increased in Southern Xinjiang and wheat planting proportions quickly decreased in Northern Xinjiang.（2）The TET of the three crops increased by 47.85%, and the largest contribution came from cotton, followed by corn and wheat for the period 1960-2010. Starting in the 2000 s, wheat was replaced by cotton as the most important part of agricultural water consumption. This indicates that the changes in cultivated areas and planting structure would affect the spatial-temporal distribution of ET as wel
出处
《地理研究》
CSSCI
CSCD
北大核心
2017年第8期1443-1454,共12页
Geographical Research
基金
新疆维吾尔自治区重点实验室开放课题(2016D03004)
国家自然科学基金国际合作与交流项目(41361140361)
国家自然科学基金项目(41671034)
国家重点研发计划子课题(2016YFC0500201-02)
关键词
种植结构
蒸散发
绿洲农田
新疆
crop planting patterns
evapotranspiration
oasis cropland
Xinjiang
