植物生态学报 ›› 2018, Vol. 42 ›› Issue (3): 337-348.doi: 10.17521/cjpe.2017.0241

• 研究论文 • 上一篇    下一篇

中国草地生态系统根系周转的空间格局和驱动因子

孙元丰1,2,万宏伟1,赵玉金1,陈世苹1,2,白永飞1,2,*()   

  1. 1 中国科学院植物研究所植被与环境变化国家重点实验室, 北京 100093
    2 中国科学院大学资源与环境学院, 北京 100049
  • 出版日期:2018-03-20 发布日期:2018-03-08
  • 通讯作者: 白永飞 E-mail:yfbai@ibcas.ac.cn
  • 基金资助:
    国家重点研发计划专项(2017YFA06047020);中国科学院战略性先导科技专项(XDA05050400)

Spatial patterns and drivers of root turnover in grassland ecosystems in China

Yuan-Feng SUN1,2,Hong-Wei WAN1,Yu-Jin ZHAO1,Shi-Ping CHEN1,2,Yong-Fei BAI1,2,*()   

  1. 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2 College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
  • Online:2018-03-20 Published:2018-03-08
  • Contact: Yong-Fei BAI E-mail:yfbai@ibcas.ac.cn
  • Supported by:
    Supported by the National Keypoint Research and Invention Program(2017YFA06047020);the Strategic Priority Research Program of the Chinese Academy of Sciences.(XDA05050400)

摘要:

根系周转是陆地生态系统物质循环的关键指标, 也是陆地生态系统净初级生产力及碳固持潜力估算的核心参数。然而, 由于地下净初级生产力数据获取困难, 区域和全球尺度上的相关研究十分有限, 尤其是分布广泛的中国草地, 区域尺度上的整合研究几乎为空白。基于样地实测数据、已发表文献和在线数据库数据, 对中国草地5种植被类型、共计154个草地生态系统根系周转的空间格局进行整合分析, 并结合气象和土壤数据, 揭示了草地生态系统根系周转的关键驱动因子。研究发现: (1)根系周转速率随纬度升高而降低, 低纬度温暖地区根系周转更快; (2)气候因子(年平均气温、年降水量)和土壤理化性质(砾石含量、容重、pH值)共同影响根系周转, 对周转变异性的解释度为44%, 其中气候因子的相对贡献率为57%, 土壤理化性质的相对贡献率为43%; (3)中国草地根系周转的格局和驱动因子与全球尺度的研究结果不尽相同。该研究对根系周转的驱动因子提出了新的观点和证据, 为全球尺度上的整合研究提供了关键数据。

关键词: 根系周转, 中国草地, 气候因子, 土壤属性, 相对贡献, 气候变化

Abstract:
Aims Root turnover rate is a key indicator of ecosystem functions and services. It is also a core parameter for estimating net primary productivity and carbon sequestration potential. However, few studies have examined the patterns and drivers of root turnover at regional and global scales, especially for the widely distributed grassland ecosystems in China. Our objective is to determine: 1) the spatial patterns of root turnover rate for grassland ecosystems in China; and 2) the mechanisms and relative contributions of abiotic and biotic factors driving the root turnover process.
Methods Root turnover data used in this study were derived from two sources. One was obtained from the sample- to-sample plot survey by Grassland Carbon Sequestration Project. The other was extracted from 43 published literatures on root turnover of grasslands in China from 1983 to 2016. These publications were collected from the ISI Web of Science or Chinese literature database. For studies in which climatic variables were not reported, climate information was extracted from the World Climate Database based on site coordinates. Soil properties were collected from Harmonized World Soil Database Version 1.1 supplied by Food and Agriculture Organization of the United Nations.
Important findings Our results showed that root turnover rate was significantly negatively correlated with latitude in China. The national scale pattern of root turnover was influenced by climatic variables (mean annual temperature and mean annual precipitation) and soil properties (gravel content, bulk density, and pH value). These variables together explained 44% of the variation in root turnover rate, with the relative contribution being 57% for climatic variables and 43% for soil properties. However, the regional scale patterns and drivers of root turnover for grasslands in China were different from those at the global scale.

Key words: root turnover, grassland in China, climatic factors, soil properties, relative contribution, climate change