生物多样性 ›› 2025, Vol. 33 ›› Issue (3): 24341.  DOI: 10.17520/biods.2024341  cstr: 32101.14.biods.2024341

• 研究报告: 生态系统多样性 • 上一篇    下一篇

北方典型草地土壤线虫代谢速率及能量流动对氮沉降和降水模式改变的响应

莫笑梅1, 张琪1, 杨嘉欣1, 郑国1, 胡中民2, 张晓珂3, 梁思维4*, 崔淑艳1,5*   

  1. 1. 沈阳师范大学生命科学学院, 沈阳 110034; 2. 海南大学生态学院, 海口 570228; 3. 中国科学院沈阳应用生态研究所, 沈阳 110016; 4. 辽宁省农业科学院耕作栽培研究所, 沈阳 110161; 5. 中国科学院动物研究所动物进化与系统学重点实验室, 北京 100101
  • 收稿日期:2024-07-29 修回日期:2024-09-09 出版日期:2025-03-20 发布日期:2025-03-24
  • 通讯作者: 崔淑艳; 梁思维

Responses of soil nematode metabolic rate and energy flow to nitrogen addition and precipitation pattern change in a typical northern grassland

Xiaomei Mo1, Qi Zhang1, Jiaxin Yang1, Guo Zheng1, Zhongmin Hu2, Xiaoke Zhang3, Siwei Liang4*, Shuyan Cui1,5*   

  1. 1 College of Life Science, Shenyang Normal University, Shenyang 110034, China 

    2 College of Ecology, Hainan University, Haikou 570228, China 

    3 Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China 

    4 Tillage and Cultivation Research Institute, Liaoning Academy of Agricultural Sciences, Shenyang 110161, China 

    5 Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China

  • Received:2024-07-29 Revised:2024-09-09 Online:2025-03-20 Published:2025-03-24
  • Contact: Shuyan Cui; Siwei Liang

摘要: 土壤线虫是一类对环境变化敏感、响应迅速的重要土壤动物, 其营养类群丰富, 横跨土壤食物网的多个营养级, 这使得土壤线虫的代谢速率和能量流动成为了衡量生态系统功能的有效指标。在全球气候变化的背景下, 我国北方温带草地在降水模式和氮沉降方面发生了巨大变化。但降水模式和氮沉降的交互作用(氮水交互)对土壤线虫的代谢速率和能量流动的影响尚不清楚。本研究通过野外试验模拟这两种全球变化因子, 在内蒙古多伦地区开展了长达8年的降水添加(降水总量相同而降水强度和频率不同, 共5个降水强度)和氮添加(10 g∙m–2∙yr–1)控制实验, 旨在探究土壤线虫代谢速率及能量流动对氮沉降和降水模式改变的响应。结果表明: 氮水交互效应对线虫的代谢速率和能量通量均有显著的消极影响。在降水模式向高强度低频率转变下, 线虫的代谢率和能量通量均呈现随降水强度增加而增加的趋势, 在高强度降水下达到峰值后降低, 而氮水交互的负效应大幅削弱了这种趋势。氮水交互下, 线虫的代谢速率和线虫食物网的能量流动可能主要由食物资源介导的上行效应控制。本研究揭示了长期氮沉降与降水模式改变的交互作用会显著抑制土壤线虫的能量代谢过程, 表明未来气候变化背景下氮水耦合效应可能通过干扰土壤微食物网能量传递削弱温带草地生态系统的功能稳定性。

关键词: 代谢速率, 能量流动, 氮添加, 降水强度, 土壤线虫

Abstract

Aims: Soil nematodes are crucial soil organisms that are highly sensitive to environmental changes. Their diverse groups occupy multiple trophic levels within the soil food web, and their metabolic rates and energy fluxes can thus serve as powerful metrics for assessing ecosystem functioning. Global climate change has resulted in significant shifts in the nitrogen deposition and precipitation pattern in northern temperate grasslands, but it remains largely unknown how these shifts and their interactions might affect soil nematode metabolic rate and energy flow. The study aims to investigate the responses of nematode metabolic rates and energy flows to the interaction between nitrogen addition and precipitation intensity change. 

Methods: We conducted an eight-year controlled experiment with precipitation and nitrogen addition in the Duolun region of Inner Mongolia. The experiment assessed five levels of precipitation intensity while maintaining a constant total and varying frequency. The experiment’s total nitrogen addition included 10 g∙m–2∙yr–1

Results: The results showed that the interaction between nitrogen addition and precipitation pattern change had significant negative impacts on nematode metabolic rate and energy flux. Under changing precipitation patterns, shifting towards higher intensity and lower frequency events, nematode metabolic rates and energy fluxes initially increased with increasing precipitation intensity, peaking at high intensity before declining. However, this trend was weakened by the effects of interactions between nitrogen addition and precipitation pattern change. Under the interaction effects of nitrogen addition and precipitation pattern change, nematode metabolic rate and energy flow were primarily driven by bottom-up effects of food resources within the nematode food web. 

Conclusions: The experiment showed that soil nematode metabolic rates and energy flows are negatively impacted by the interaction between nitrogen addition and precipitation pattern change. This research provides insights into the impacts of multi-factor interactions on underground biological communities in the context of global climate change.

Key words: metabolic rate, energy flow, N addition, precipitation intensity, soil nematode