中国地理科学 ›› 2018, Vol. 28 ›› Issue (1): 12-24.doi: 10.1007/s11769-017-0899-1

• 论文 • 上一篇    下一篇

Spatio-temporal Variation of Soil Respiration and Its Driving Factors in Semi-arid Regions of North China

ZENG Xinhua1,2, SONG Yigang3, ZHANG Wanjun2, HE Shengbing1   

  1. 1. College of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China;
    2. Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China;
    3. Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai 201602, China
  • 收稿日期:2016-03-10 修回日期:2016-07-08 出版日期:2018-02-27 发布日期:2018-01-04
  • 通讯作者: HE Shengbing, ZHANG Wanjun E-mail:heshengbing@sjtu.edu.cn;zhangwj@sjziam.ac.cn
  • 基金资助:

    Under the auspices of Strategic Priority Research Program of Chinese Academy of Sciences (No. XDA05060600), National Natural Science Foundation of China (No. 51378306)

Spatio-temporal Variation of Soil Respiration and Its Driving Factors in Semi-arid Regions of North China

ZENG Xinhua1,2, SONG Yigang3, ZHANG Wanjun2, HE Shengbing1   

  1. 1. College of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China;
    2. Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China;
    3. Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai 201602, China
  • Received:2016-03-10 Revised:2016-07-08 Online:2018-02-27 Published:2018-01-04
  • Contact: HE Shengbing, ZHANG Wanjun E-mail:heshengbing@sjtu.edu.cn;zhangwj@sjziam.ac.cn
  • Supported by:

    Under the auspices of Strategic Priority Research Program of Chinese Academy of Sciences (No. XDA05060600), National Natural Science Foundation of China (No. 51378306)

摘要:

Soil respiration (SR) is the second-largest flux in ecosystem carbon cycling. Due to the large spatio-temporal variability of environmental factors, SR varied among different vegetation types, thereby impeding accurate estimation of CO2 emissions via SR. However, studies on spatio-temporal variation of SR are still scarce for semi-arid regions of North China. In this study, we conducted 12-month SR measurements in six land-use types, including two secondary forests (Populus tomentosa (PT) and Robinia pseudoacacia (RP)), three artificial plantations (Armeniaca sibirica (AS), Punica granatum (PG) and Ziziphus jujuba (ZJ)) and one natural grassland (GR), to quantify spatio-temporal variation of SR and distinguish its controlling factors. Results indicated that SR exhibited distinct seasonal patterns for the six sites. Soil respiration peaked in August 2012 and bottomed in April 2013. The temporal coefficient of variation (CV) of SR for the six sites ranged from 76.98% to 94.08%, while the spatial CV of SR ranged from 20.28% to 72.97% across the 12-month measurement. Soil temperature and soil moisture were the major controlling factors of temporal variation of SR in the six sites, while spatial variation in SR was mainly caused by the differences in soil total nitrogen (STN), soil organic carbon (SOC), net photosynthesis rate, and fine root biomass. Our results show that the annual average SR and Q10 (temperature sensitivity of soil respiration) values tended to decrease from secondary forests and grassland to plantations, indicating that the conversion of natural ecosystems to man-made ecosystems may reduce CO2 emissions and SR temperature sensitivity. Due to the high spatio-temporal variation of SR in our study area, care should be taken when converting secondary forests and grassland to plantations from the point view of accurately quantifying CO2 emissions via SR at regional scales.

关键词: soil respiration, spatio-temporal variation, substrate availability, temperature sensitivity, global carbon cycle, North China

Abstract:

Soil respiration (SR) is the second-largest flux in ecosystem carbon cycling. Due to the large spatio-temporal variability of environmental factors, SR varied among different vegetation types, thereby impeding accurate estimation of CO2 emissions via SR. However, studies on spatio-temporal variation of SR are still scarce for semi-arid regions of North China. In this study, we conducted 12-month SR measurements in six land-use types, including two secondary forests (Populus tomentosa (PT) and Robinia pseudoacacia (RP)), three artificial plantations (Armeniaca sibirica (AS), Punica granatum (PG) and Ziziphus jujuba (ZJ)) and one natural grassland (GR), to quantify spatio-temporal variation of SR and distinguish its controlling factors. Results indicated that SR exhibited distinct seasonal patterns for the six sites. Soil respiration peaked in August 2012 and bottomed in April 2013. The temporal coefficient of variation (CV) of SR for the six sites ranged from 76.98% to 94.08%, while the spatial CV of SR ranged from 20.28% to 72.97% across the 12-month measurement. Soil temperature and soil moisture were the major controlling factors of temporal variation of SR in the six sites, while spatial variation in SR was mainly caused by the differences in soil total nitrogen (STN), soil organic carbon (SOC), net photosynthesis rate, and fine root biomass. Our results show that the annual average SR and Q10 (temperature sensitivity of soil respiration) values tended to decrease from secondary forests and grassland to plantations, indicating that the conversion of natural ecosystems to man-made ecosystems may reduce CO2 emissions and SR temperature sensitivity. Due to the high spatio-temporal variation of SR in our study area, care should be taken when converting secondary forests and grassland to plantations from the point view of accurately quantifying CO2 emissions via SR at regional scales.

Key words: soil respiration, spatio-temporal variation, substrate availability, temperature sensitivity, global carbon cycle, North China