[1]JIA Jianying,HE Nan,HAN Lanying,et al.Variation Characteristics of Precipitation and Soil Water Storage in Winter Wheat Field During Fallow Period in Rainfed Area of the Loess Plateau[J].Research of Soil and Water Conservation,2022,29(06):97-103.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
29
Number of periods:
2022 06
Page number:
97-103
Column:
Public date:
2022-10-20
- Title:
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Variation Characteristics of Precipitation and Soil Water Storage in Winter Wheat Field During Fallow Period in Rainfed Area of the Loess Plateau
- Author(s):
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JIA Jianying1, HE Nan2, HAN Lanying1, WAN Xin1, WANG Xing1, LIANG Yun1, WANG Xiaowei1, WANG Fan1, HUANG Pengcheng1
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(1.Lanzhou Regional Climate Center, Lanzhou 730020, China; 2.Public Weather Service Center, China Meteorological Administration, Beijing 100081, China)
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- Keywords:
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soil water storage; precipitation threshold; water storage efficiency; summer fallow period; Loess Plateau
- CLC:
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S161; S152
- DOI:
-
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- Abstract:
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In order to improve the utilization efficiency of precipitation resources in fallow period and ensure regional food security, we collected the soil moisture data of winter wheat fields and meteorological observation data from 1981 to 2020 to analyze the variation characteristics of precipitation and soil moisture in rainfed area of the Longdong in the Loess Plateau. The results showed that:(1)in the past 40 years, the precipitation during the fallow period of the Longdong in the Loess Plateau increased at a rate of 14 mm/decade, but the inter-annual difference was large; the numbers of rainfall days and the light rain days decreased, while the number of moderate and heavy rain days showed a slightly increasing trend; the increase of rainfall intensity had a greater contribution to the increase of precipitation;(2)the obvious water-filling process in 1 m soil layer was observed in the fallow period, increasing at a rate of 9.5 mm/10 days, and the average water storage capacity increased by 97 mm in the past 40 years; the increment of water storage was the lowest in the 1990s, but it increased significantly since this century;(3)there was a quadratic function relation between the precipitation and the soil water storage in 1 m soil layer during the fallow period; the precipitation threshold of 1 m soil layer starting to store moisture during the fallow period was175 mm; the water storage increment had a high correlation with the total days of moderate and heavy rain; early precipitation during the fallow period was mainly consumed by soil evaporation, and most of the precipitation in the later period was stored in the soil;(4)in recent 40 years, the average soil water storage efficiency of 1 m soil layer was 0.27 for winter wheat fields during the fallow period, and the water storage efficiency decreased linearly with the increasing of soil moisture during winter wheat harvest; when the water storage of 1 m soil layer during wheat harvest was less than 45%~48% of the soil water holding capacity, the water storage efficiency was higher; there was also a quadratic function relation between precipitation and soil water storage efficiency during the fallow period, and the precipitation threshold for soil moisture fully supplemented in 1 m soil layer was 388 mm. This study reveals the transformation processes of precipitation and soil water storage in the fallow period in Longdong of the Loess Plateau in the past 40 years, and provides a scientific basis for guiding the efficient utilization of regional water resources.