Evaluation of cotton production under limited water resources in the arid region of Xinjiang, China
Evaluation of cotton production under limited water resources in the arid region of Xinjiang, China
复制标题
新疆干旱区水资源有限条件下棉花生产评价
作者：
Aiqin Zhao;Wei Xiuju
中国是世界上最大的棉花生产国、消费国和进口国，新疆是中国最大的棉花产区。新疆的棉花生产直接关系到当地农民的收入水平，也对整个棉花产业的发展起着举足轻重的作用。新疆地处干旱地区，农业全靠灌溉。随着新疆城市化的发展，水资源受到污染。与此同时，由于气候变化和新疆淡水资源的减少，新疆农业水资源短缺问题日益严重。因此，农业仍然需要降低用水率。膜下滴灌技术已被证明是一项巨大的成功。本文利用大尺度水氮耦合模型，对有限供水条件下新疆棉花膜下滴灌的生产潜力进行了估算。2000年以来，新疆棉花种植面积呈现波动上升趋势。在棉价上涨和政府补贴的鼓励下，2017年以后棉花种植面积大幅增加，棉花种植面积几乎达到最大值。2020年新疆棉花种植总面积2×106公顷。到2020年，预计农业最大可用水量为4.95×1010 m3，棉花单位面积可用水量约为3860 m3/ha。但根据我们的模型，南疆和北方的最佳灌溉量分别为6040和5520 m3/ha，皮棉单产潜力分别为2845和2384 kg/ha。受2020年棉花单产水量的限制，采用膜下滴灌技术，2020年南疆和北方皮棉单产可分别达到2721和2185 kg/ha，全疆皮棉总产可达到5.1×106 t。这一产量将比当地政府预期的目标（4.2×106吨）高出21%
China is the world's largest cotton producer, consumer and importer, and Xinjiang is China's largest cotton producing area. The cotton production in Xinjiang is directly related to the income level of local farmers and also plays an important role in the development of the whole cotton industry. Xinjiang is situated in an arid region, and all agriculture in Xinjiang depends on irrigation. With the development of urbanization in Xinjiang water resources have become polluted. Meanwhile, as a result of climate change and the decrease in the availability of the fresh water in Xinjiang, the shortage of water for agriculture becomes increasingly serious. Thus, there is a continuing need for agriculture to reduce its water use rate. A mulched drip irrigation technique has been proven a great success. In this paper we used a large scale water and nitrogen coupling model, to estimate Xinjiang cotton production potential using mulched drip irrigation under the limited water supply. Since 2000, the cotton planting area in Xinjiang has shown a fluctuating and increasing trend. Encouraged by the increase of cotton price and government subsidies, the cotton planting area increased significantly after 2017, and the cotton planting area almost reached a maximum. The total cotton planting area in Xinjiang will be 2×106 ha in 2020. In 2020 the estimated maximum amount of water available for agriculture will be 4.95×1010 m3 and the available water per unit area for cotton will be approximately 3860 m3/ha. But according to our model, the optimal irrigation rate in southern and northern Xinjiang is 6040 and 5520 m3/ha respectively, and the lint yield potential per unit area is 2845 and 2384 kg/ha, respectively. Limited by the amount of water per unit area for cotton in 2020, the lint yield per unit area in southern and northern Xinjiang in 2020 could respectively reach 2721 and 2185 kg/ha, and the total lint yield in Xinjiang could reach 5.1×106 tonnes, by using mulched drip-irrigation. This yield will be 21% higher than the target expected by the local government (4.2×106 tonnes)