欢迎访问《草业学报》官方网站,今天是

草业学报 ›› 2025, Vol. 34 ›› Issue (9): 26-37.DOI: 10.11686/cyxb2024412

• 研究论文 • 上一篇    下一篇

地上净初级生产力对植物物种丰富度的响应及影响因子分析

罗叙1(), 马慧2, 韩翠1, 赵雅欣1, 赵莹1, 谢应忠1,3, 李建平1,3()   

  1. 1.宁夏大学林业与草业学院,宁夏 银川 750021
    2.甘肃亚盛薯业集团有限责任公司,甘肃 榆中 730100
    3.盐池北部荒漠草原宁夏野外科学观测研究站,宁夏 盐池 751500
  • 收稿日期:2024-10-22 修回日期:2024-12-13 出版日期:2025-09-20 发布日期:2025-07-02
  • 通讯作者: 李建平
  • 作者简介:E-mail: lijianpingsas@163.com
    罗叙(1995-),男,甘肃白银人,在读博士。E-mail: luoxu181226@163.com
  • 基金资助:
    国家自然科学基金(32160336);宁夏自然科学基金(2023AAC02029);宁夏自然科学基金(2023AAC03092);宁夏大学草学一流学科建设项目(NXYLXK2017A01)

Response of aboveground net primary productivity to plant species richness and identification of the factors of influence

Xu LUO1(), Hui MA2, Cui HAN1, Ya-xin ZHAO1, Ying ZHAO1, Ying-zhong XIE1,3, Jian-ping LI1,3()   

  1. 1.College of Forestry and Prataculture,Ningxia University,Yinchuan 750021,China
    2.Gansu Yasheng Potato Group Co. ,Ltd,Yuzhong 730100,China
    3.Northern Yanchi Desert Steppe Observation and Research Station of Ningxia,Yanchi 751500,China
  • Received:2024-10-22 Revised:2024-12-13 Online:2025-09-20 Published:2025-07-02
  • Contact: Jian-ping LI

摘要:

草地生态系统的生产力在很大程度上受优势种和次优势种的影响。然而,关于优势种和次优势种不同组合建植的物种丰富度对地上生产力影响的研究相对较少。因此,为探究优势和次优势植物群落生产力的直接和间接驱动因素,本研究选取了宁夏北部盐池荒漠草原的3个优势种和7个次优势种进行单播和混播试验。确定了5个植物物种丰富度(单播,4、6、8和10种混播),并考察了不同物种组合的地上生物量、土壤微生物群落组成和胞外酶活性以及土壤理化性质。结果表明:1)优势种和次优势种混播均增加了优势细菌门(放线菌门、酸杆菌门和变形菌门)和优势真菌门(子囊菌门和担子菌门)的总相对丰度,优势细菌门总相对丰度的增加比优势真菌门明显。2)单播和混播的矢量长度为1.31~1.38,矢量角度均>45°。土壤微生物代谢主要受土壤碳(C)和磷(P)限制,单播土壤氮磷比(N/P)显著高于4种混播群落(P<0.05)。3)地上净初级生产力与物种丰富度表现出显著正相关关系(P<0.001),互补性效应和选择效应对所观察到的地上净初级生产力均有显著的积极贡献。4)结构方程模型(structural equation model, SEM)表明植物物种丰富度通过选择效应、互补效应和土壤理化性质间接积极影响植物群落地上生产力。研究结果将为保护草地生物多样性和加强草地生态系统恢复提供数据支持和理论指导。

关键词: 植物物种丰富度, 微生物群落, 土壤酶化学计量, 土壤特性, 生产力

Abstract:

The productivity of grassland ecosystems is largely influenced by their dominant and subdominant species. However, relatively few studies have explored the effects of species richness established by different combinations of dominant species and subdominant species on aboveground productivity. Therefore, to explore the direct and indirect driving factors of dominant and subdominant plant community productivity, we conducted monoculture and mixed-culture experiments using three dominant species and seven subdominant species from the Yanchi desert steppe in northern Ningxia. Five degrees of plant species richness (monoculture and 4-, 6-, 8-, and 10-species mixtures) were established, and the aboveground biomass, soil microbial community composition, extracellular enzyme activity, and soil physicochemical properties were investigated in each group. The results show that: 1) Mixtures of both dominant species and subdominant species increased the total relative abundance of the dominant bacterial phyla (Actinobacteriota, Acidobacteriota and Proteobacteria) and dominant fungal phyla (Ascomycota and Basidiomycota), and the increase in the total relative abundance of dominant bacterial phyla was more obvious than that of dominant fungal phyla. 2) The vector length of monocultures and mixed cultures ranged from 1.31 to 1.38, and the vector angle was greater than 45°. Soil microbial metabolism was mainly limited by soil carbon and phosphorus. The nitrogen∶phosphorus was significantly higher in monoculture soil than in 4-species mixed-culture soil (P<0.05). 3) There was a significant positive correlation between aboveground net primary productivity and species richness (P<0.001), and both the complementarity effect and the selection effect made significant positive contributions to the observed net primary aboveground productivity. 4) The structural equation model showed that plant species richness indirectly and positively affected aboveground productivity of the plant community through a selection effect, a complementarity effect, and soil physical and chemical properties. The results of this study provide data support and theoretical guidance for devising strategies to protect grassland biodiversity and strengthen grassland ecosystem restoration.

Key words: plant species richness, microbial community, soil enzyme stoichiometry, soil characteristics, productivity