| 摘要: |
| 【目的】分析青铜峡灌区1998—2017年引水量时空变化规律，解析各影响因素的作用程度。【方法】采用线性倾向估计法分析青铜峡灌区及各分灌区1998—2017年的引水变化趋势，采用Pearson相关系数法分析了灌区引水量和水源条件、灌溉需求以及灌溉效率之间的相关性。【结果】①时间上，青铜峡灌区及分灌区银川灌区、银南灌区和银北灌区引水量年际均呈下降趋势，下降速率分别为13.3亿、5.7亿、5.2亿和2.5亿m3/10 a；年内引水主要集中在灌溉期5—8月和冬灌期10—11月，灌溉期引水量减少较为显著。②空间上，灌区单位面积灌溉水量均呈下降趋势，下降速率呈显著的空间差异性特征，且不同时期单位面积灌水量空间分布格局发生显著变化，从1998—2002年的灌区中部最大、南部次之、北部最小的空间分布转变为2013—2017年的灌区东南部最大、灌区中部和西南部次之、灌区北部最小的分布格局，最大单位面积灌溉水量区域由灌区中部转移到灌区东南部。③相关性分析表明，灌区引水量与灌溉效率的相关性最强；灌区引水量与灌溉需求的相关性次之，其中青铜峡灌区、银川灌区和银南灌区引水量与种植结构因子呈强相关性；灌区引水量与水源条件的相关性相对较弱。【结论】过去20 a来，大力推广节水灌溉，灌溉效率显著提升是驱动青铜峡灌区引水量下降的主要因素，其次是灌溉需求，水源条件对灌区引水量的影响相对微弱。 |
| 关键词: 灌区；引水量；影响因素；变化趋势 |
| DOI：10.13522/j.cnki.ggps.2019478 |
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| Variation in Water Diverted to the Qingtongxia Irrigation District and Its Determinants |
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LIU Kuan, ZHAI Jiaqi, ZHAO Yong, DONG Yiyang, LI Haihong
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1.State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China; 2. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China
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| Abstract: |
| 【Objective】Agricultural production in Qingtongxia irrigation district relies on water diverted from the Yellow river, which depends on many factors. In this paper, we analyzes its trend over the past two decades as well as the determinants underlying the trend.【Method】The analysis was based on data measured from 1998-2017, and the temporal trend in the diverted water for the whole district and the sub-irrigation districts was calculated using the tendency estimation method. The correlation between the diverted water, water availability, demand of irrigation for water, and irrigation efficiency was analyzed using the Pearson correlation coefficient method.【Result】①The water diverted to Qingtongxia irrigation district, Yinchuan irrigation district, Yinnan irrigation district and Yinbei irrigation district had trended down at rate of 1 330, 570, 520 and 250 million m3 per decade respectively. Intra-annual water diversion was mainly from May to August for summer irrigation, and from October to November for winter irrigation. ②Although the water used by per unit area had trended down in general, there was a spatiotemporal variation across the region. In 1998—2002, water used per unit area for irrigation was the highest in the center followed by the south in the region, whereas the lowest was in the north. While the north still used least water per unit area in 2013—2017, the area that consumed most per unit area had shifted to south, followed by the center and the northwest. ③Water diversion correlated with irrigation efficiency most significantly, followed by irrigation demand. There was a strong correlation between water diversion and planting structure in Qingtongxia, Yinchuan and Yinnan irrigated districts, whereas no correlation was found between water diversion and water source. 【Conclusion】The development in water-efficient irrigation over the past 20 years was the main reason underlying the decline in water diversion from the Yellow river, followed by decrease in irrigation demand. The water sources did not have a noticeable impact on water diversion. |
| Key words: Qingtongxia; irrigation district; diversion water; determinants |
