干旱区生态环境知识资源中心(Arid): 考虑排盐和控盐的干旱区暗管布局参数研究

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	考虑排盐和控盐的干旱区暗管布局参数研究
其他题名	Subsurface drains layout in arid areas with purposes of salt control and discharge
	钱颖志; 朱焱; 伍靖伟; 黄介生
来源期刊	农业工程学报
ISSN	1002-6819
出版年	2019
卷号	35 期号:13 页码:74-83
中文摘要	为研究干旱盐碱地区排盐暗管工程布局参数的确定方法,该文利用新疆蓄水淋洗、暗管排水排盐试验数据,建立并验证了HYDRUS-2D数学模型,土壤含水率均方根误差范围为0.038~0.043 cm~3/cm~3,决定系数为0.82~0.95;土壤含盐量均方根误差范围为1.6~5.15 g/kg,决定系数为0.95~0.99,所建立的模型能够模拟淋洗和暗管协同作用下的土壤水盐运移规律。考虑干旱区排盐和控盐的多重需要,提出了排淋比作为暗管排盐的评价指标,并结合传统的脱盐率指标,定量分析了不同暗管布局参数(埋深和间距)和土壤质地条件对暗管排盐的影响。结果表明:暗管埋深对脱盐率影响不大,影响根系区脱盐率的主要因素是暗管间距,脱盐率与暗管间距近似呈指数关系;而暗管间距和埋深对于排淋比都有显著影响;当土壤饱和渗透系数较大时,土壤饱和渗透系数对脱盐率没有明显影响,而排淋比与土壤饱和渗透系数呈指数关系,可见,排淋比比脱盐率更加适用于评价暗管排盐效率。该文进一步建立了排淋比与暗管布局(埋深和间距)以及土壤饱和渗透系数的经验公式。经比较,在计算的壤土情况下,当设计排淋比为500%时,该文拟合公式计算得到暗管间距与《规范》公式一致,当设计要求较低时,拟合公式所得暗管布局较为经济。该经验公式可用于指导确定干旱区暗管布局参数。
英文摘要	Subsurface drainage has been widely used to prevent saline-alkali soil. However, it remains a concern to determine the layout of subsurface drains in arid areas while considering its complex hydrogeological conditions, e.g., deep groundwater table, arid climate, and strong spatial soil heterogeneity. Therefore, it is necessary to investigate the method of determining layout parameters, e.g., spacing and depth of subsurface drains in arid region. The leaching salt will move upward due to strong evaporation in arid areas, which limits the evaluation index of desalination rate to evaluate the effect of subsurface drains. So, there are 3 major objects in this study: 1) to define an additional evaluation index to evaluate the effect of subsurface drains; 2) to determine relationship between the layout parameters of subsurface drains and the effects of subsurface drains for controlling or discharging soil salt; and 3) to evaluate the impacts of soil characteristics on effects of subsurface drains for controlling or discharging soil salt. The evaluation index, ratio of salt discharge to leaching, is defined and used with desalination rate to evaluate the effects of subsurface drains for controlling or discharging soil salt. The experimental data of salt leaching under the subsurface drainage condition in Xinjiang was used to calibrate and validate the HYDRUS-2D model. 16 scenarios of numerical experiments were implemented to calculate the soil salt transport under different layout parameters of subsurface drains with 6 different spacing (100, 200, 300, 500, 1 000, 1 500 cm) under 3 different depths (60, 100, 150 cm). 1 scenario without subsurface drain was carried out for comparison. The soil salinity and desalination rate as well as ratio of salt discharge to leaching were calculated for evaluation. In addition, 4 different soil types (loam, silt, silt loam, sandy clay loam) under the same depth of 1 m and spacing of 10 m were used to analyze the effect of soil texture on the effects of salt leaching and discharge of subsurface drains. The results showed that the simulation values were in good agreement with observed ones, and the established model could simulate soil water and salt transport under subsurface drains. The spacing of the subsurface drains showed strong impact on the desalination rate while no obvious impact was found from the depth of the subsurface drains and soil characteristics. There was an exponential relationship between the desalination rate and spacing of subsurface drains. The spacing and depth of the subsurface drains and the soil characteristics had significant effects on the ratio of salt discharge to leaching. The exponential and linear relationship between ratio of salt discharge to leaching with the spacing and depth could be established, and also the ratio of salt discharge to leaching was exponentially related to saturated hydraulic conductivity. The empirical formula of the desalination rate and ratio of salt discharge to leaching with the layout parameters of subsurface drains under the specific soil and leaching schedule was established. The ratio of salt discharge to leaching was considered as a more appropriate evaluation index in arid areas because it could clearly distinguish leaching and discharging salt and it was sensitive to the layout parameters and soil characteristics.
中文关键词	盐分 ; 脱盐 ; 含水率 ; 暗管 ; 间距 ; 埋深 ; 渗透系数 ; 排淋比
英文关键词	salinity desalination water content subsurface drains spacing buried depth permeability coefficient ratio of salt discharge to leaching
语种	中文
国家	中国
收录类别	CSCD
WOS类目	AGRICULTURAL ENGINEERING
WOS研究方向	Agriculture
CSCD记录号	CSCD:6550205
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/239351
作者单位	武汉大学, 水资源与水电工程科学国家重点实验室, 武汉, 湖北 430072, 中国
推荐引用方式 GB/T 7714	钱颖志,朱焱,伍靖伟,等. 考虑排盐和控盐的干旱区暗管布局参数研究[J],2019,35(13):74-83.
APA	钱颖志,朱焱,伍靖伟,&黄介生.(2019).考虑排盐和控盐的干旱区暗管布局参数研究.农业工程学报,35(13),74-83.
MLA	钱颖志,et al."考虑排盐和控盐的干旱区暗管布局参数研究".农业工程学报 35.13(2019):74-83.