State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
State Key Lab of Urban and Regional Ecology, Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Total Environ. 2019 Jan 10;647:1323-1332. doi: 10.1016/j.scitotenv.2018.08.037. Epub 2018 Aug 4.
In water-restricted erosive mountains environments, large-scale vegetation plantation and diverse terracing measures have been widely used as the most powerful ecological-restoration tools to control water erosion and improve local degraded ecosystems, further enhancing the complexity of terracing, vegetation, and soil water relationships. In this study, 70 sampling sites across different hillslopes were selected and used for biweekly soil water measurement in a typical loess hilly catchment of China. The most typical terracing measures (broad bench terraces-BBT, narrow bench terraces-NBT, level ditch terraces-LDT, counter-slope terraces-CST, and half-moon terraces-HMT) and introduced vegetation types (wild peach, apricot, arborvitae, poplar, and Chinese pine) were included in the study. Based on multi-site measurements, the effects of terracing and vegetation on the profile of soil moisture dynamics at a depth of 2 m were analyzed. Results show that terracing generally has a very positive role in soil water enhancement. Compared with slope risers, terracing can increase soil moisture by 0.87% (±0.82%) to 37.71% (±9.01%), which benefits ecological restoration. However, the effects of various terracing measures on soil water differed. BBT measures were the most powerful in soil water recharge, with an incremental ratio of 21.88%, which is 4.94, 5.95 and 4.21 times that of CST (5.19%), LDT (4.43%) and NBT (3.68%), respectively. The existence of different plant communities can increase the uncertainties and complexities of soil water status. Introduced trees and shrubs generally induce a greater reduction in soil water than do natural plants in similar environmental conditions. The few remaining original hillslopes covered by natural grasses can better preserve soil water, because of large differences in water use strategies between planted and natural species. Such findings are expected to provide important references for the proper selection of terracing and artificial vegetation toward enhancing the efficiency of water conservation and ecological restoration in dry and degraded regions.
在水资源受限的侵蚀性山区环境中，大规模植被种植和多样化的梯田措施已被广泛用作控制水蚀和改善当地退化生态系统的最有力的生态恢复工具，进一步增加了梯田、植被和土壤水分关系的复杂性。在这项研究中，选择了中国典型黄土丘陵流域的 70 个不同山坡的采样点，进行了为期两周的土壤水分测量。本研究包括最典型的梯田措施（宽阶梯田-BBT、窄阶梯田-NBT、水平沟梯田-LDT、反坡梯田-CST 和半月形梯田-HMT）和引入的植被类型（野生桃树、杏树、柏木、杨树和油松）。基于多站点测量，分析了梯田和植被对 2m 深度土壤水分动态剖面的影响。结果表明，梯田对土壤水分增加具有非常积极的作用。与坡段相比，梯田可增加土壤水分 0.87%（±0.82%）至 37.71%（±9.01%），有利于生态恢复。然而，各种梯田措施对土壤水分的影响不同。BBT 措施在土壤水分补给方面最为有效，增量比为 21.88%，分别是 CST（5.19%）、LDT（4.43%）和 NBT（3.68%）的 4.94、5.95 和 4.21 倍。不同植物群落的存在会增加土壤水分状况的不确定性和复杂性。在类似的环境条件下，引入的树木和灌木一般会导致土壤水分减少得更多，而天然植物则会减少得更少。在少数保留下来的天然草地覆盖的原始山坡上，可以更好地保持土壤水分，因为种植和天然物种的用水策略有很大的差异。这些发现有望为在干旱和退化地区选择适当的梯田和人工植被提供重要参考，以提高节水和生态恢复的效率。
