Moisture-retaining and transmissibility properties of soil profiles with different architectures in dolomite karst areas
-
摘要: 喀斯特区整体土层浅薄且分布不连续,土层和基岩构成了不同的土体构型剖面,而这些剖面的持水导水性能之间是否存在差异,目前尚缺乏清楚的认识。本文通过BEST单环入渗方法研究了喀斯特白云岩区三种土体构型土壤剖面(深厚土层剖面(DS)、浅薄土层剖面(SS)以及土石混合剖面(SR))的持水性能和导水性能。试验结果表明,不同土壤剖面的持水性能、导水性能主要受不同层次土壤颗粒组成特征及剖面构型影响。三种剖面表层土壤都具有较高的导水能力,以SR表层饱和导水率(Ks)最高,可达244.1 mm?h-1,而SS表层Ks为56.8 mm?h-1。DS除表层和风化层外,土壤黏重,导水能力较弱,但是体现出较高的持水能力;SS整体导水能力较弱,持水能力较好;SR土壤疏松,整体持水、导水能力均较好,土石层导水能力相对最差而持水能力最好。就土壤有效水含量而言,SR最高,DS和SS由于土壤较黏重,有效水含量相对较低。该研究结果可为喀斯特地区植被恢复位点的选择提供科学指导和理论依据。Abstract: In karst areas, soil is generally shallow and discontinuous, where unevenly distributed soil beds and bedrock in soil profiles with different architectures. Whether their moisture-retaining and transmissibility properties are variable remains unclear. To address this issue, the BEST single-ring infiltrometer method was employed to investigate such soil profiles in a dolomite karst area, namely, deep soil profile (DS), shallow soil profile (SS) and soil-rock mixture profile (SR), respectively. The results show that the hydraulic properties above mentioned of these profiles are different, which are mainly affected by soil particle component and profile architecture features. The surface soil of three kinds of soil profiles have high water conductivity, among which surface Ks of the soil-rock mixture profile(SR) is the highest, up to 244.1 mm?h-1, while the surface Ks of shallow soil profile(SS) is only 56.8 mm?h-1. For deep soil profile (DS), the soil is clayey and of low water conductivity but of high water holding capacity except for surface soil and regolith layers. Due to the impact of underlying bedrock, shallow soil profile(SS) shows low water conductivity and high water holding capacity as a whole. In the soil-rock mixture profile (SR), loose soil beds have both good water conductivity and holding capacity, while the rock layer has relatively poor water conductivity but better water holding capacity. In the soil’s effective water content, the SR is the highest, while DS and SS are relatively lower due to the clayey soils. The results of this study could provide scientific guidance for the selection of vegetation restoration sites in karst areas.
-
[1] 袁道先. 我国西南岩溶石山的环境地质问题[J]. 世界科技研究与发展, 1997, 19(5): 41-43. [2] 王世杰, 李阳兵. 喀斯特石漠化研究存在的问题与发展趋势[J]. 地球科学进展, 2007, 22(6): 573-582 . [3] Nie Y P, Ding Y L, Zhang H L, et al. Comparison of woody species composition between rocky outcrops and nearby matrix vegetation on degraded karst hillslopes of Southwest China [J]. Journal of Forestry Research, 2019, 30(3): 911-920. [4] 邢丹, 肖玖军, 韩世玉, 等. 基于稳定同位素的石漠化地区桑树根系水来源研究[J]. 农业工程学报, 2019, 35(15):77-84. [5] 邹巧云, 陈洪松, 马星宇, 等. 基于控水试验的喀斯特出露基岩生境植物水分来源分析[J]. 应用生态学报, 2019, 30(3):759-767. [6] Nie Y P, Chen H S, Wang K L, et al. Water source utilization by woody plants growing on dolomite outcrops and nearby soils during dry seasons in karst region of Southwest China [J]. Journal of Hydrology, 2011, 420-421: 264-274. [7] Gregory L, Wilcox B P, Shade B, et al. Large-scale rainfall simulation over shallow caves on karst shrublands [J]. Ecohydrology, 2009, 2: 72-80. [8] Peng T, Wang S J. Effects of land use, land cover and rainfall regimes on the surface runoff and soil loss on karst slopes in southwest China [J]. Catena, 2012, 90: 53-62. [9] 陈洪松, 杨静, 傅伟, 等. 桂西北喀斯特峰丛不同土地利用方式坡面产流产沙特征[J]. 农业工程学报, 2012, 28(16): 121-126. [10] Chen H S, Liu J W, Zhang W, et al. Soil hydraulic properties on the steep karst hillslopes in northwest Guangxi, China [J]. Environmental Earth Sciences, 2012, 66(1): 371-379. [11] Fu T G, Chen H S, Zhang W, et al. Vertical distribution of soil saturated hydraulic conductivity and its influencing factors in a small karst catchment in Southwest China [J]. Environmental Monitoring and Assessment, 2015, 187(3): 92. [12] Yang J, Nie Y P, Chen H S, et al. Hydraulic properties of karst fractures filled with soils and regolith materials: Implication for their ecohydrological functions [J]. Geoderma, 2016, 276: 93-101. [13] Chen H S, Liu J W, Wang K L, et al. Spatial distribution of rock fragments on steep hillslopes in karst region of northwest Guangxi, China [J]. Catena, 2010, 84(1): 21-28. [14] Schwen A, Zimmermann M, Bodner G. Vertical variations of soil hydraulic properties within two soil profiles and its relevance for soil water simulations [J]. Journal of Hydrology, 2014,516: 169-181. [15] 胡传旺, 王辉, 刘常, 等. 南方典型土壤水力特征差异性分析[J]. 水土保持学报, 2017, 31(2): 97-102 . [16] 杨静, 陈洪松, 聂云鹏, 等. 典型喀斯特峰丛洼地降雨特性及浅层地下水埋深变化特征[J]. 水土保持学报, 2012, 26(5): 239-243. [17] Lassabatère L, Angulo-Jaramillo R, Soria Ugalde JM, et al. Beerkan estimation of soil transfer parameters through infiltration experiments-BEST [J]. Soil Science Society of America Journal, 2006, 70: 521-532. [18] 雍晨旭, 樊军, 王胜. 坡度对3种单环法测量坡地饱和导水率的影响[J]. 中国水土保持科学, 2018, 16(2): 24-30. [19] Zhao P P, Shao M A, Wang T J. Spatial distributions of soil surface-layer saturated hydraulic conductivity and controlling factors on dam farmlands [J]. Water Resources Management, 2010, 24(10): 2247-2266. [20] Fu Z Y, Chen H S, Zhang W, et al. Subsurface ?ow in a soil-mantled subtropical dolomite karst slope: A ?eld rainfall simulation study [J]. Geomorphology, 2015, 250: 1-14. [21] Wang S, Fu Z Y, Chen H S, et al. Mechanisms of surface and subsurface runoff generation in subtropical soil-epikarst systems: Implications of rainfall simulation experiments on karst slope [J]. Journal of Hydrology, 2020, 580:1-13. [22] Sohrt J, Ries F, Sauter M, et al. Significance of preferential flow at the tock soil interface in a semi-arid karst environment [J]. Catena, 2014, 123: 1-10.
点击查看大图
计量
- 文章访问数: 1402
- HTML浏览量: 596
- PDF下载量: 166
- 被引次数: 0