三江源高寒草甸水源涵养功能及土壤理化性质对退化程度的响应.pdf

第 32 卷 第 6 期Vol.32，No.616-292023 年 6 月草业学报ACTA PRATACULTURAE SINICA孙玉，杨永胜，何琦，等.三江源高寒草甸水源涵养功能及土壤理化性质对退化程度的响应.草业学报，2023，32（6）：1629.SUN Yu，YANG Yong-sheng，HE Qi，et al.Responses of soil water conservation function and soil physicochemical properties to a range of degradation conditions in alpine meadows of the Three River Headwater Region.Acta Prataculturae Sinica，2023，32（6）：1629.三江源高寒草甸水源涵养功能及土壤理化性质对退化程度的响应孙玉1，2，杨永胜2*，何琦1，2，王军邦3，张秀娟1*，李慧婷4，徐兴良3，周华坤2，张宇恒5（1.长江大学园艺园林学院，湖北 荆州 434025；2.中国科学院西北高原生物研究所，青海省寒区恢复生态学重点实验室，中国科学院高原生物适应与进化重点实验室，青海 西宁 810001；3.中国科学院地理科学与资源研究所，生态系统网络观测与模拟重点实验室，北京 100101；4.西宁市北山林场，青海 西宁 810001；5.荆门市规划勘测设计研究院，湖北 荆门 448000）摘要：土壤持水能力和土壤理化性质是衡量水源涵养功能的重要指标，掌握其变化特征对高寒草甸的生态保护和修复具有重要意义。本研究选择三江源区的果洛藏族自治州玛沁县作为实验区，通过野外调查和室内实验相结合的方法，分析了不同退化程度对高寒草甸土壤持水能力、理化性质影响及两者的相关性。研究结果表明：1）高寒草甸010 cm 土层内随退化程度的加剧饱和持水量、毛管持水量、田间持水量呈下降趋势，退化程度对表层 05 cm 土壤的持水能力的影响最为显著，与原生植被相比，重度退化样地 05 cm 土层的饱和持水量、毛管持水量和田间持水量分别显著降低 51.99%、56.28%、59.93%（P0.05）。2）随退化程度的加剧，高寒草甸 05 cm 土壤全氮、全磷、全碳逐渐下降，全钾无显著变化，与原生植被相比，重度退化样地 05 cm 土层的全碳、全氮、全磷分别显著降低41.95%、65.88%、21.82%（P0.05）；在 010 cm 的土层内土壤有机碳、总孔隙度呈下降趋势，土壤 pH、容重呈显著增加的趋势。3）通过冗余分析得出，饱和持水量、毛管持水量、田间持水量与土壤全氮、毛管孔隙度呈显著相关关系（P0.05），其中，与毛管孔隙度呈极显著正相关关系（P0.01）；饱和持水量、毛管持水量、田间持水量与土壤容重、pH呈极显著负相关关系（P0.01）；毛管孔隙度、土壤全钾与田间持水量无相关关系，两者是决定饱和导水率的因素。说明高寒草甸退化对表层土壤的影响最为显著，加强表层土壤的保护是维持水源涵养功能的关键所在。关键词：高寒草甸；退化；土壤；理化性质；持水能力；冗余分析Responses of soil water conservation function and soil physicochemical properties to a range of degradation conditions in alpine meadows of the Three River Headwater RegionSUN Yu1，2，YANG Yong-sheng2*，HE Qi1，2，WANG Jun-bang3，ZHANG Xiu-juan1*，LI Hui-ting4，XU Xing-liang3，ZHOU Hua-kun2，ZHANG Yu-heng51.College of Horticulture and Gardening，Yangtze University，Jingzhou 434025，China；2.Key Laboratory of Adaptation and Evolution of Plateau Organisms，Chinese Academy of Sciences，Qinghai Key Laboratory of Restoration Ecology in Cold Region，Northwest Institute of Plateau Biology，Chinese Academy of Sciences，Xining 810001，China；3.Key Laboratory of Ecosystem Network Observation and Modeling，Institute of Geographical Sciences and Natural Resources，Chinese Academy of Sciences，Beijing 100101，China；4.Beishan Forest Farm，Xining City，Xining 810001，China；5.Jingmen Planning and Survey Design Institute，DOI：10.11686/cyxb2022291http：/收稿日期：2022-07-24；改回日期：2022-09-15基金项目：国家自然基金联合项目（U20A2006），国家自然基金青年项目（32001149），青海省应用基础研究项目（2022-ZJ-716），国家自然基金面上项目（31971507），中国科学院青海省人民政府三江源国家公园联合研究专项（LHZX-2020-10）和中国科学院青年促进会（2022436）资助。作者简介：孙玉（1998-），女，河南周口人，在读硕士。E-mail： 通信作者 Corresponding author.E-mail：，第 32 卷第 6 期草业学报 2023 年Jingmen 448000，China.Abstract：The soil water-holding capacity and physicochemical properties are important indicators of the water conservation function of soil，and it is important to understand how these factors change under various condition for the ecological protection and restoration of alpine meadows.In this study，we analyzed the effects of different degradation levels on the soil water-holding capacity and physicochemical properties of soil in alpine meadows，as well as correlations between these factors，in both field and laboratory-based experiments.The filed experiments were conducted in Maqin County，Guoluo Tibetan Autonomous Prefecture，in the Three River Headwater Region.The main findings were as follows：1）The saturation water-holding capacity，capillary water-holding capacity，and field water-holding capacity of the 0-10 cm soil horizon of alpine meadows decreased with increasing severity of degradation.The degradation level had the most significant effect on the water-holding capacity in the 0-5 cm soil surface horizon.Compared with soil at the native vegetation site，soil at the heavily degraded site showed significantly decreased（P0.05）saturation water-holding capacity，capillary water-holding capacity，and field water-holding capacity in 0-5 cm soil horizon decreased by 51.99%，56.28%，and 59.93%，respectively.2）With increasing severity of degradation，the total nitrogen，total phosphorus，and total carbon contents in the 0-5 cm soil horizon gradually decreased，but there was no significant change in total potassium content.Compared with soil at the native vegetation site，the soil at the heavily degraded site showed significantly decreased（P0.05）contents of total C，total N，and total P in the 0-5 cm soil horizon decreased by 41.95%，65.88%，and 21.82%，respectively.As the severity of degradation increased，the soil organic carbon content and total porosity showed a decreasing trend，and soil pH and bulk density showed a significant increasing trend.3）A redundancy analysis showed that saturated water-holding capacity，capillary water-holding capacity，and field water-holding capacity were significantly correlated with total soil N and capillary porosity（P0.05），and the positive correlation with capillary porosity was highly significant（P0.01）.The saturated water-holding capacity，capillary water-holding capacity，and field water-holding capacity were significantly negatively correlated with soil bulk density and pH（P0.05），Capillary porosit