三峡水库消落带优势植物不同配置对土壤结构稳定性的影响  

Soil structure stability impacted by the different configurations of dominant plant species in the riparian zone of Three Gorges Reservoir

作　　者：胡宏宇 张靖 刘莹 冉义国 王小晓[1,2] 黄平 HU Hongyu;ZHANG Jing;LIU Ying;RAN Yiguo;WANG Xiaoxiao;HUANG Ping(Key Laboratory of Reservoir Aquatic Environment,Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,Chongqing 400714,China;Chongqing School,University of Chinese Academy of Sciences,Chongqing 400714,China)

机构地区：[1]中国科学院重庆绿色智能技术研究院,中国科学院水库水环境重点实验室,重庆400714 [2]中国科学院大学重庆学院,重庆400714

出　　处：《生态学报》2025年第6期2710-2722,共13页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(42377320,41771266);三峡后续工作规划项目(5000002021BF40001);中国科学院西部青年学者项目(202082)。

摘　　要：土壤结构稳定性是衡量退化生态系统功能恢复和维持的关键指标。探究优势植物配置对土壤结构稳定性的影响,对于三峡水库消落带的植被恢复与岸线稳定具有重要意义。选择三峡水库消落带优势植物狗牙根(G)、香附子(X)和苍耳(C),设置空白(CK)、单种(G、X、C)、两两混种(GX、CX、CG)三种不同处理,利用Yoder湿筛法和计算机断层扫描技术(Computed Tomography,CT)对土壤团聚体粒径分布和土壤孔隙特征进行测定,对比分析了不同植物配置对土壤团聚体粒径分布与稳定性及土壤孔隙结构的影响。结果表明:1)相比于CK处理,不同植物配置处理下土壤团聚体(>0.25 mm)的质量百分比均有增加。植物根系的生长促进了土壤团聚体的形成与稳定,但并未达到显著水平。2)香附子单种及其与狗牙根的混种均抑制了土壤大孔隙的形成,可能由于香附子根系不发达,且其膨大的根结在生长过程中压缩了周围的土壤孔隙。然而,对于狗牙根和苍耳,无论是单种还是混种都会促进土壤大孔隙的发育。3)植物根系性状与土壤团聚体稳定性和土壤孔隙结构具有显著相关性,根长(RL)和根表面积(RSA)是影响土壤团聚体稳定性的关键根系性状,根长(RL)、根表面积(RSA)和根体积(RV)是控制土壤孔隙结构的关键性状。因此,为了有效提升土壤结构的稳定性,可以基于植物的根长、根表面积等根系功能性状,筛选出适合脆弱生态系统植被恢复的先锋或优势植物,并进行合理配置。该结果可为三峡水库消落带及相似区域的水土保持和生态恢复中的植物遴选与群落配置提供基础数据和理论支持。Soil structure stability is crucial for evaluating the restoration and maintenance of degraded ecosystem functions.Plant growth has been found to exert various influences on the evolution of soil structure,through both direct and indirect mechanisms.Understanding how different configurations of dominant plant species impact soil structure stability is essential for optimizing restoration strategies in degraded ecosystems.This is particularly important in regions prone to erosion and habitat degradation,such as the riparian zones of large reservoirs.We selected three dominant plant species from the riparian zone of the Three Gorges Reservoir:Cynodon dactylon(G),Cyperus rotundus(X),and Xanthium sibiricum(C).Three treatment groups were implemented:control(CK),single species(G,X,C),and two-species mixtures(GX,CX,CG).Soil aggregates were assessed using Yoder′s wet sieving method,and soil pore characteristics were examined through computed tomography(CT).The aim was to compare the effects of different plant configurations on the size distribution and stability of soil aggregates and soil pore structure.The results showed that:1)The mass percentage of soil aggregates larger than 0.25 mm increased under all plant configurations treatments compared to the CK treatment.Plant root growth facilitated the formation and stabilization of soil aggregates,although the effect was not statistically significant.2)Cyperus rotundus,whether planted alone or in mixture with Cynodon dactylon,inhibited the formation of soil macropores.This was likely due to its underdeveloped root system and the compressive effect of its enlarged root nodules on the surrounding soil pores during growth.In contrast,Cynodon dactylon and Xanthium sibiricum,either planted individually or in mixtures,consistently promoted the development of soil macropores.3)Plant root traits exhibited significant correlations with both soil aggregate stability and soil pore structure.Root length(RL)and root surface area(RSA)were identified as the primary traits influencing

关 键 词：植物配置 根系性状 土壤结构 团聚体 土壤孔隙 

分 类 号：S15[农业科学—土壤学]