[1]ZHANG Jingxiao,L Wang,WANG Xing,et al.Experimental Study on Characteristics of the Infiltration in the Deep Drying Loess Under Nature Rainfall[J].Research of Soil and Water Conservation,2021,28(02):141-148.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
28
Number of periods:
2021 02
Page number:
141-148
Column:
Public date:
2021-02-06
- Title:
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Experimental Study on Characteristics of the Infiltration in the Deep Drying Loess Under Nature Rainfall
- Author(s):
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ZHANG Jingxiao1, LÜ Wang2, WANG Xing3, LU Mei1, HAN Chao1, JING Ming
2
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(1.Hebei University of Warer Resources and Electric Engineering, Cangzhou, Hebei 061000, China; 2.Yellow River Institute of Hydraulic Research, Zhengzhou 450003, China; 3.School of Agriculture, Ningxia University, Yinchuan 750021, China)
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- Keywords:
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rainfall; soil moisture; depth of infiltration; wetting front; amount of cumulative infiltration
- CLC:
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S152.7; TV93
- DOI:
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- Abstract:
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In order to explore the capacity of natural rainfall infiltration, and to study the mechanism of rainfall infiltration in the drying soil in the loess area, a field soil column up to 10 m was established to simulate the jujube forests drying soil in Mizhi experimental station which is located in the north of Shaanxi Province. By using the CS650-CR1000 automatic system, changes of soil moisture within different depths were observed continuously under natural conditions during the period 2014—2019. The results were as follows.(1)Under the conditions of heavy rain with daily rainfall of 33.6 mm and 35.6 mm(the rainfall intensities were 3.73 mm/h and 2.97 mm/h, as well, the duration was 9.0 h and 12.0 h, respectively), the maximum infiltration depths were 140 cm and 100 cm, and the cumulative infiltration amounts were up to 20.05 and 16.10 mm, respectively. Under the conditions of moderate rain with daily rainfall of 19.0 mm and 16.8 mm(the rainfall intensities were 2.24 mm/h and 1.53 mm/h, as well, the duration was 8.5 h and 11.0 h, respectively), the maximum infiltration depths were 90 cm and 60 cm, and the cumulative infiltration amounts were up to 8.12 mm and 9.77 mm, respectively. And under the conditions of light rain with daily rainfall of 9.6 mm and 8.8 mm(the rainfall intensities were 1.48 and 0.76 mm/h, as well, the duration was 6.5 h and 11.5 h, respectively), the maximum infiltration depths were 30 cm and 20 cm, and the cumulative infiltration amounts were up to 1.05 mm and 0.23 mm, respectively.(2)The depths of wetting front(Zi)increases with time(T), which follows the power function Zi=aTb.(3)The duration of infiltration includes two stages, namely from the beginning of the rain to the end, and from the cessation of rainfall to the end of infiltration. The infiltration depths of the 6 typical rainfall events(33.6 mm, 35.6 mm, 19.0 mm, 16.8 mm, 9.6 mm, 8.8 mm)were 100 cm, 60 cm, 70 cm, 40 cm, 30 cm, 20 cm in the period from the cessation of rainfall to the end of infiltration, and the infiltration amounts were 9.86 mm, 10.78 mm, 2.09 mm, 8.42 mm, 1.05 mm, and 0.23 mm, respectively. During the duration of infiltration, the coefficients of the 6 rainfall infiltration were 0.60, 0.45, 0.43, 0.58, 0.11 and 0.03. The infiltration depths were greatly affected by precipitation, intensity, and duration of the rainfall in the loess hilly region. Increasing the precipitation of the rainfall was helpful to improve the recharge coefficient and could promote the effective water restoration of dry soil in this region. This study was of great importance to understand the natural restoration ability of the drying soil in the Loess Plateau under the conditions of bare land, and could provide a strong theoretical support for the sustainable utilization of the drying soil.