晋西黄土区典型人工林与天然林林下植被物种多样性差异及其影响因素  

Differences and influencing factors of understory vegetation species diversity between typical plantations and natural forests in the loess area of western Shanxi Province,northern China

作　　者：王宇宁 冯天骄 孙龙[3] 刘茜茹 刘亚博 王平[1,2] Wang Yuning;Feng Tianjiao;Sun Long;Liu Xiru;Liu Yabo;Wang Ping(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;Jixian National Forest Ecosystem Observation and Research Station,Beijing 100083,China;Research Center for Eco-Environment,State Key Laboratory of Urban and Regional Ecology,Chinese Academy of Sciences,Beijing 100085,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]山西吉县森林生态系统国家野外科学观测研究站,北京100083 [3]中国科学院生态环境研究中心城市与区域生态国家重点实验室,北京100085

出　　处：《北京林业大学学报》2025年第4期103-116,共14页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(42371114);国家生态科学数据中心开放基金项目(NESDC20210201);中国科学院退化生态系统植被恢复与管理重点实验室开放基金(VRMDF2303)。

摘　　要：【目的】晋西黄土区长期植被恢复显著改善了生态环境,但不同树种恢复后林下植被多样性的影响因素尚不明确。本研究旨在探讨典型人工林与辽东栎次生林的林下植被物种多样性差异及其驱动机制,揭示林分生长参数和土壤性质对草本层多样性的调控作用,为黄土高原植被恢复与生态系统管理提供科学依据。【方法】选取晋西黄土区典型人工林(油松林、侧柏林、刺槐林)与天然林(辽东栎次生林)的随机样地作为调查对象,测定林分生长参数(生物量、株高、冠幅、丛径等)及土壤性质(容重、孔隙度、全氮、全磷、全钾、速效养分等),计算2017、2020、2023年林下植被α多样性和β多样性,采用主成分分析、相关性分析和冗余分析解析多样性驱动因子。【结果】(1)油松林与侧柏林草本层α多样性指数整体较稳定,其Simpson指数显著高于辽东栎次生林(P<0.05);(2)辽东栎次生林草本层物种多样性显著低于人工林,但其林下植被平均生物量和冠幅最高,表明优势种竞争抑制多样性;(3)长期植被恢复下,4个林分的土壤质量稳步提升,土壤全钾与PIE指数(r=−0.334)、Margalef指数(r=−0.394)呈极显著负相关(P<0.01);(4)草本冠幅(贡献度24.6%)和地下生物量(贡献度20.9%)是多样性下降的主控因子。【结论】人工林通过调控土壤养分平衡可优化林下植被多样性,而辽东栎次生林需结合适度干扰缓解优势种竞争。研究结果为黄土高原植被恢复与生物多样性维持提供了理论支持与实践指导。[Objective]Long-term vegetation restoration in the loess area of western Shanxi Province of northern China has significantly improved the ecological environment.However,the factors influencing understory vegetation diversity following the restoration of different tree species remained unclear.This study aimed to explore the differences in species diversity of understory vegetation between typical plantations and Quercus liaotungensis secondary forests,to reveal the regulatory effects of stand growth parameters and soil properties on herb layer diversity,and to provide a scientific basis for vegetation restoration and ecosystem management in the Loess Plateau.[Method]Random plots of typical plantations(Pinus tabuliformis forest,Platycladus orientalis forest,and Robinia pseudoacacia forest)and natural forests(Quercus liaotungensis secondary forest)in the loess area of western Shanxi Province were selected as study sites.Stand growth parameters(biomass,plant height,crown width,cluster diameter,etc.)and soil properties(bulk density,porosity,total nitrogen,total phosphorus,total potassium,available nutrients,etc.)were measured.Theα-diversity andβ-diversity of understory vegetation in 2017,2020,and 2023 were calculated.Principal component analysis,correlation analysis,and redundancy analysis(RDA)were employed to identify the driving factors of diversity.[Result](1)Theαdiversity index of herb layer in Pinus tabuliformis forest and Platycladus orientalis forest was relatively stable,and their Simpson index were significantly higher than that in Quercus liaotungensis secondary forest(P<0.05).(2)The species diversity of herb layer in Quercus liaotungensis secondary forest was significantly lower than that in plantations,but the average biomass and crown width of understory vegetation were the highest,indicating that competition from dominant species suppressed diversity.(3)The soil quality of four stands improved steadily under long-term vegetation restoration.Soil total potassium was significantly negatively correlated

关 键 词：黄土高原 林下植被 多样性指数 植被恢复 

分 类 号：S718.551[农业科学—林学]