摘要
为研究淮北平原冻融期潜水蒸发规律,采用五道沟水文实验站 38 套原状土蒸渗仪 1991 2018 年试验资料,采用非线性拟合方法,揭示了冻融期(12 2 月)砂姜黑土和黄潮土有无作物潜水蒸发变化规律。结果表明,淮北平原冻融期多表现为昼融夜冻现象,砂姜黑土和黄潮土有无作物潜水蒸发均随埋深的增大呈先增后减趋势,在埋深 0.1~0.3 m区间出现最大值,且种植小麦潜水蒸发量比裸地小。裸地情景下高斯函数拟合最好,拟合优度 R2 均大于 0.9,其中砂姜黑土冻融期 12 2 月潜水蒸发量最大时埋深平均值在 0.08 m 左右,黄潮土在 0.29 m 左右。小麦生长情景下类高斯函数拟合最好,拟合优度 R2均大于 0.9,其中砂姜黑土冻融期潜水蒸发最大值对应的埋深为 0,潜水蒸发随埋深递减,而黄潮土对应的埋深在 0.23 m 左右,2 种土壤有作物时最大值对应的埋深均比裸地小。拟合的函数形式可直接用于冻融期旬潜水蒸发量的计算。
This paper was aimed to study phreatic evaporation in Huaibei Plain during freezing-thawing period. The data was collected from long-term experiments at Wudaogou Hydrological Experimental Station from 1990 to 2018. In the experiments, a total of 38 lysimeters were installed. About half of them were planted with winter wheat. The others were bare lands. The soils in lysimeters were typical local soils: undisturbed lime concretion black soil and yellow moist soil. Soil temperature and air temperature were measured. The phreatic evaporation was determined and its relationship with soil depth was fitted with non-linear regression equations. According to the air temperature, the freezing-thawing period in the Huaibei Plain was from December to the next February. During the period, the soil was characterized with freezing at night and thawing during the day. The freezing layer was thin. In bare land, the phreatic evaporation increased firstly with depth and then decreased. The maximum phreatic evaporation occurred in the depth range of 0.1-0.3 m in the both soils. When the depth was smaller than the 0.1 m, phreatic evaporation increased with depth while it decreased with the depth when the depth was higher than 0.3 m. The characteristics of phreatic evaporation in soil profile during the freezing-thawing period was different from that in the period. The change of phreatic evaporation in the wheat land was similar with that in the bare land. However, the phreatic evaporation in the wheat land was smaller than that in the bare land when the depth was smaller than 0.4 m in lime concretion black soil and smaller than 1.0 m in the yellow moist soil. It was because the capillary was probably cut off due to covering on soil surface caused by roots or stalk residues or tillage before sowing, which affected the transport of water along the capillary and caused small phreatic evaporation. There was a peak in the phreatic evaporation curves. Therefore, 3 forms of distribution functions were selected to fit the change of phreatic evaporation with depth. Meanwhile, popular phreatic evaporation equations were compared. The Gaussian function could yield the best simulation for the phreatic evaporation in the bare land with the determination coefficient higher than 0.9 and the root mean square error smaller than 0.1. During the freezing-thawing period, the maximum phreatic evaporation from the lime concretion black soil occurred at 0.08 m below ground surface but at 0.29 m in yellow moist soil below ground surface. For wheat lands, the quasi-Gauss function was the best for constructing phreatic evaporation simulation formula with the determination coefficient higher than 0.9. The maximums of phreatic evaporation from the lime concretion black soil and the yellow moist occurred on the soil surface and 0.23 m below the soil surface, respectively. The soil depth corresponding to maximum phreatic evaporation was smaller in the wheat land than bare land.
作者
王振龙
杨秒
吕海深
胡永胜
朱永华
顾南
王怡宁
Wang Zhenlong;Yang Miao;Lü Haishen;Hu Yongsheng;Zhu Yonghua;Gu Nan;Wang Yining(Key Laboratory on Water Conservancy and Water Resources of Anhui Province, Anhui & Huaihe River Institute of Hydraulic Research, Bengbu 233000, China;School of Science, Hohai University, Nanjing 211100, China;College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China;Nanjing Hydraulic Research Institute, Nanjing 210029, China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2019年第13期129-137,共9页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家重点研发计划课题“湖沼系统生态需水核算及调控技术”(2017YFC0404504)
国家自然科学基金项目(41830752、41571015)
关键词
冻
融
蒸发
地下水
淮北平原
freezing
thaw
evaporation
groundwater depth
Huaibei Plain