• 研究报告 •

### 绿洲农田土壤优先流特征及其对灌溉量的响应

1. (1中国科学院寒区旱区环境与工程研究所中国生态系统研究网络临泽内陆河流域研究站/中国科学院内陆河流域生态水文重点实验室,  兰州 73000;  2中国科学院大学,  北京 100049)
• 出版日期:2015-05-18 发布日期:2015-05-18

### Characteristics of the preferential flow and its response to irrigation amount in oasis cropland.

YAN Jia-liang1,2, ZHAO Wen-zhi1, ZHANG Yong-yong1

1. (1Linze Inland River Basin Research Station, Chinese Ecosystem Research Network/ Key Laboratory of Inland River Ecohydrology, Cold and Arid Regions, Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; 2University of Chinese Academy of Sciences, Beijing 100049, China)
• Online:2015-05-18 Published:2015-05-18

Abstract: Preferential flow is a physical process describing how water and solutes move along certain pathways through soil profile. Studying the cropland preferential flow patterns and its influential factors could quantify the deep percolation, improve water and fertilizer use efficiency and reduce the risk of agrochemicals contaminating shallow groundwater in oasis cropland. The dye tracer experiments were carried out in field oasis cropland, using a brilliant blue FCF solution. The results showed that between ridge and furrow, the number of stained paths densities differed significantly at the 7.3-16.7 cm depth of the soil profiles, while the maximum dye depth had no significant difference. The main influence factors of the maximum stained depth were the irrigation amount and the ant burrows. The maximum stained depth was (43.1±5.9) cm with the mean irrigation amount of 120 mm, however, the maximum stained depth was (68.3±7.6) cm with the irrigation amount of 55 mm under the influence of the ant burrows. Root played an important role in preferential flow, but only the fine roots (Φ≤2 mm) were significantly related to the preferential flow in oasis cropland, while the coarse roots were not. In oasis cropland, the characteristics of the preferential flow were influenced by the irrigation amount, the furrow and ridge planting, the ant burrows and the roots, and the ant burrows were an uncertain factor which affected the maximum infiltration depth of the preferential flow.