植物生态学报 ›› 2018, Vol. 42 ›› Issue (3): 361-371.DOI: 10.17521/cjpe.2017.0066

• 研究论文 • 上一篇    下一篇

不同载畜率处理下短花针茅荒漠草原生态系统净碳交换特征

靳宇曦,刘芳,张军,韩梦琪,王忠武*(),屈志强,韩国栋*()   

  1. 内蒙古农业大学草原与资源环境学院, 呼和浩特 010019
  • 出版日期:2018-03-20 发布日期:2018-05-17
  • 通讯作者: 王忠武,韩国栋
  • 基金资助:
    国家自然科学基金(31270502);国家自然科学基金(31260124);中国科学院战略性先导科技专项(XDA050000);中国科学院战略性先导科技专项(XDA05050402-6);国家重点研发计划(2016YFC0500504);内蒙古自治区重大科技专项和中国科学院西部之光项目(2016YFC0500504)

Net ecosystem carbon exchange characteristics in Stipa breviflora desert steppe with different stocking rates

JIN Yu-Xi,LIU Fang,ZHANG Jun,HAN Meng-Qi,WANG Zhong-Wu*(),QU Zhi-Qiang,HAN Guo-Dong*()   

  1. College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010019, China
  • Online:2018-03-20 Published:2018-05-17
  • Contact: Zhong-Wu WANG,Guo-Dong HAN
  • Supported by:
    Supported by the National Natural Science Foundation of China(31270502);Supported by the National Natural Science Foundation of China(31260124);the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA050000);the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA05050402-6);the International Key Science Research Program(2016YFC0500504);the Science and Technology Projects in Inner Mongolia Autonomous Region and the West Light Foundation of Chinese Academy of Sciences.(2016YFC0500504)

摘要:

草地生态系统是我国最大的陆地生态系统, 其碳循环的动态变化在全球碳收支平衡中扮演着重要角色。放牧是草地生态系统的主要利用方式。不同的放牧利用强度对草地生态系统会产生不同的影响。该文采用便携式光合仪LI-6400和密闭式箱法于2014-2016年生长季(5-10月)测定了3个载畜率处理(对照、轻度放牧和重度放牧)的生态系统净碳交换, 同步测定了土壤10 cm温度和湿度, 探讨载畜率、水热因素对短花针茅(Stipa breviflora)荒漠草原碳交换的影响。结果表明: 载畜率对生态系统净碳交换有显著影响, 随着载畜率的增加, 生态系统净碳交换、生态系统呼吸以及生态系统总初级生产力分别降低了48.6%、35.3%、40.4%。重度放牧显著降低了草地的固碳能力, 但轻度放牧对草地的固碳能力没有显著影响。年际间生态系统净碳交换主要受降水调控。整个生长季, 短花针茅荒漠草原均表现为碳吸收, 土壤温度对生态系统净碳交换的贡献率高于土壤湿度。

关键词: 短花针茅荒漠草原, 载畜率, 生态系统净碳交换, 生态系统呼吸, 生态系统总初级生产力

Abstract:

Aims Grassland ecosystem is the largest terrestrial ecosystem type in China. The dynamic changes in carbon cycle play an important role in global carbon budget balance. Grazing is the main use of grassland ecosystem. Different grazing intensity has different effects on the grassland ecosystem.

Methods In the growing seasons (May to October) from 2014 to 2016, we used portable optical LI-6400 and the method of static chamber to measure net ecosystem carbon exchange in Stipa breviflora desert steppe with 3 different stocking rates (CK, no grazing control; LG, lightly grazing; HG, heavily grazing). At the same time, the soil temperature and moisture of 10 cm depth were also measured. The effects of stocking rate and hydrothermal factors on the carbon exchange were discussed.

Important findings Stocking rate had a significant impact on net ecosystem carbon exchange. With the increase of stocking rate, the net ecosystem carbon exchange, ecosystem respiration, gross ecosystem productivity decreased by 48.6%, 35.3% and 40.4% respectively. Heavily grazing significantly reduced grassland carbon sequestration, but lightly grazing had no significant effect. The inter-annual changes in net carbon exchange was mainly controlled by precipitation. Throughout the growing season, Stipa breviflora desert steppe were carbon sinks. The contribution of soil temperature to the variations of net ecosystem carbon exchange was higher than that of soil moisture.

Key words: Stipa breviflora desert steppe, stocking rate, net ecosystem carbon exchange, ecosystem respiration, gross ecosystem productivity