摘要
为探究草原露天矿区不同类型土壤的水平扩散特征,以内蒙古鄂尔多斯市伊旗武家塔矿区的原状土、矿山堆积土和生态改造土3种不同立地类型的土壤为对象,通过土壤质地、扩散率、含水率等测试试验,采用HYDRUS-1D软件,对原状土、矿山堆积土和生态改造土入渗特性进行数值模拟,分析各因素对矿区土壤入渗规律的影响,探讨草原露天矿区不同类型土壤水平扩散过程的影响及变化规律。结果表明,在一维水平入渗运动条件下,原状土、堆积土、生态改造土3种不同粒径土壤的湿润锋运移距离与时间曲线整体呈现相似变化,随着入渗时间的增加,湿润锋运移距离呈现先快速增加,后缓慢推进趋势。同一种土壤类型条件下,土壤的湿润锋到达土柱最末端所需时间与土层深度呈反比关系,随着土层深度的增加,所需时间逐渐减少,且平均扩散速率更快;在同一入渗时间下,湿润锋运移距离与土层深度呈正比关系,随着土层深度增加,湿润锋运移距离也相应增大。Boltzmann参数(λ)随着土壤含水率的增加而逐渐减小,各土壤的λ~θ关系曲线随土壤含水率的增加呈现下降趋势。当θ达到某一临界值之后,λ急剧减少,原状土、堆积土和改造土各土层θ临界值略有差异,原状土各土层的θ临界值为0.29,堆积土各土层分别为0.24,0.28,0.30,而生态改造土除60—90 cm外,其余土层的θ临界值为0.31。通过HYDRUS-1D模型结合水平土柱剖面含水量变化对土壤水力参数进行反演,模拟3种土壤面含水量的变化,R 2均大于0.91,纳什效率系数(NSE)均大于0.95,均方根误差(RMSE)均小于0.20。利用HYDRUS-1D模型反演土壤水力参数模拟矿区劣质土壤水平入渗过程,能较好地模拟入渗过程,描述矿区不同土地类型的土壤水分动态变化规律,为矿区的土壤水分动态监管及生态治理提供参考依据。
In order to explore the horizontal diffusion characteristics of different soil types of in the grassland open-pit mining area,three different soil types including undisturbed soil,mine accumulation soil and ecological transformation soil in Wujiata mining area of Yiqi,Ordos City and Inner Mongolia were taken as the objects.The soil texture,diffusion rate and water content were measured,and the infiltration characteristics of undisturbed soil,mine accumulation soil and ecological transformation soil were numerically simulated by HYDRUS-1D software,so as to analyze the influence of various factors on the soil infiltration law in mining area,and to explore the influence and variation law of horizontal diffusion process of different types of soil in grassland open-pit mine area.The results show that under the condition of one-dimensional horizontal infiltration movement,the wetting front migration distance and time curve of three different particle sizes of undisturbed soil,accumulated soil and ecologically modified soil show similar changes as a whole:with the increase of infiltration time,the wetting front migration distance increases rapidly at first and then slowly advances.Under the same soil type,the time required for the wetting front to reach the end of the soil column is inversely proportional to the soil depth:with the increase of soil depth,the time required decreases gradually,and the average diffusion rate is faster;under the same infiltration time,the wetting front migration distance is proportional to the soil depth:with the increase of soil depth,the wetting front migration distance also increases accordingly.The Boltzmann parameterλdecreased with the increase of soil moisture content,and theλ~θrelationship curve of each soil showed a decreasing trend with the increase of soil moisture content.Whenθreaches a certain critical value,λdecreases sharply,and the critical values ofθin each soil layer of undisturbed soil,accumulation soil and modified soil are slightly different.The critical values of�
作者
陈功
刘虎
魏占民
CHEN Gong;LIU Hu;WEI Zhanmin(Water Conservancy and Civil Engineering College of Inner Mongolia Agricultural University,Hohhot 010018;Institute of Water Resources for Pastoral Area Ministry of Water Resources,Hohhot 010020)
出处
《水土保持学报》
CSCD
北大核心
2023年第2期76-82,89,共8页
Journal of Soil and Water Conservation
基金
内蒙古自治区科技计划项目(2019GG027,2020GG0181,2021GG0060)
中央引导地方科技发展项目(2021ZY0031)。
关键词
劣质土壤
水平扩散率
草原露天矿区
水平土柱法
poor-quality soil
horizontal diffusion rate
grassland open-pit area
horizontal soil column method
