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草业学报 ›› 2023, Vol. 32 ›› Issue (9): 27-38.DOI: 10.11686/cyxb2022446

• 研究论文 • 上一篇    下一篇

三江源地区人工克隆植物群落生物多样性对初级生产力的影响及机制

刘增辉1(), 卢素锦1, 王雨欣1, 张春辉2, 尹鑫1()   

  1. 1.青海大学生态环境工程学院,青海 西宁 810016
    2.青海大学省部共建三江源生态与高原农牧业国家重点实验室,青海 西宁 810016
  • 收稿日期:2022-11-10 修回日期:2023-01-04 出版日期:2023-09-20 发布日期:2023-07-12
  • 通讯作者: 尹鑫
  • 作者简介:E-mail: yinx18@163.com
    刘增辉(1997-),男,山西临汾人,在读硕士。E-mail: 1337096936@qq.com
  • 基金资助:
    青海省自然科学基金青年项目(2019-ZJ-947Q);国家自然科学基金地区科学基金项目(32060385)

Effects of biodiversity on primary productivity and its mechanism in artificially sown clonal plant communities of the Sanjiangyuan region

Zeng-hui LIU1(), Su-jin LU1, Yu-xin WANG1, Chun-hui ZHANG2, Xin YIN1()   

  1. 1.College of Eco-Environment Engineering,Qinghai University,Xining 810016,China
    2.State Key Laboratory of Plateau Ecology and Agriculture,Qinghai University,Xining 810016,China
  • Received:2022-11-10 Revised:2023-01-04 Online:2023-09-20 Published:2023-07-12
  • Contact: Xin YIN

摘要:

克隆植物具有独特的竞争和繁殖方式,这可能会使其构建的群落呈现不一样的生物多样性-生态系统功能关系,但是本议题却极少被研究。本研究利用垂穗披碱草、花苜蓿和鹅绒委陵菜构建了一个生物多样性试验,并将单播和混播重复3次,且将垂穗披碱草作为所有混播的固定物种,以此跨越两个生长季测试生物多样性对生产力的影响。本研究发现,物种丰富度和地上生物量之间并没有线性正相关关系,但是大多数混播的净多样性效应(NE)都是显著的,且NE主要来源于非特征依赖性互补效应(TICE)。较强的TICE主要来自地上垂直空间的互补性利用;其次来自底层物种鹅绒委陵菜光吸收能力的增强。沿着时间和物种丰富度梯度,垂穗披碱草的优势度增强,鹅绒委陵菜的优势度下降,致使特征依赖型互补效应(TDCE)和优势度效应(DE)随之增强,但是它们对NE的贡献有限。另外,以上3种效应均随时间增强。总之,本研究的结果表明克隆植物群落表现出了不一样的多样性-生产力关系模式,并且这种多样性效应主要来自地上垂直空间的互补性利用。

关键词: 植物多样性-生产力关系, 克隆植物, 净多样性效应, 非特征依赖性互补效应, 植物性状

Abstract:

Clonal plants have unique ways to compete and reproduce, and their unique traits may lead to a particular biodiversity-productivity relationship in communities they form. However, this issue has rarely been studied. In this research, a biodiversity experiment was set up using three clonal species (Elymus nutansMedicago ruthenica and Potentilla anserine) in monocultures and mixtures. There were three replicates, E. nutans was used as the fixed species in all mixtures and the effects of biodiversity on productivity were assessed over two years. We found that the net biodiversity effects (NE) were significant in nearly all mixtures in our experiment, attributable to strong trait-independent complementary effects (TICE), although there was no positive linear relationship between species richness and aboveground biomass. The strong TICE was predominantly caused by the complementary utilization of aboveground vertical space, while a secondary cause was the enhancement of light absorption capacity of the understorey species P. anserine. Meanwhile, the dominance of E. nutans increased over time and with increasing species richness, whereas P. anserine displayed the opposite tendencies, resulting in an increase in trait-dependent complementary effect (TDCE) and dominance effect (DE) for communities where P. anserine was present. However, the contributions of those two mechanisms to NE were limited. Furthermore, all those effects increased with time. The results of this study indicate that clonal species display a different biodiversity-productivity relationship from the normally positive linear pattern, due to the complementary use of aboveground vertical space.

Key words: the biodiversity-productivity relationship, clonal plants, net biodiversity effects, trait-independent complementary effect, plant traits