Chin J Plan Ecolo ›› 2018, Vol. 42 ›› Issue (3): 277-287.DOI: 10.17521/cjpe.2015.0329

• Research Articles • Previous Articles     Next Articles

Carbon stock and seasonal dynamics of carbon flux in warm-temperature tussock ecosystem in Shandong Province, China

LI Yong-Qiang1,2,DONG Zhi3,DING Chen-Xi3,WANG Ya-Mei1,JIA Ji-Wen1,ZHANG Jia-Nan1,JIAO Shu-Ying1,*()   

  1. 1 National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources; College of Resources and Environment, Shandong Agricultural University, Taian, Shandong 271018, China
    2 College of Ecological and Environmental Sciences, Inner Mongolia Agricultural University, Hohhot 010018, China
    3 Forestry College of Shandong Agriculture University, Forestry Ecological Station, Tai’an, Shandong 271018, China ;
  • Online:2018-03-20 Published:2017-06-16
  • Contact: Shu-Ying JIAO ORCID:0000-0003-4499-2243
  • Supported by:
    Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0505040303);the National Natural Science Foundation of China (31302014), the China Postdoctoral Science Foundation(31302014);the China Postdoctoral Science Foundation(2011M501158);the Natural Science Foundation of Shandong Province, China(ZR2009DQ007);the Special Fund of China Postdoctoral Science Foundation(2012T50589)

Abstract:

Aims The project was to analyze the carbon stock, seasonal dynamics of carbon flux and the responses of net ecosystem CO2 exchange (NEE) to various environmental factors of Zoysia japonica warm tussock ecosystem in Shandong Province.

Methods We used field sampling and fixed-point observation-static chamber method (LI-840 infrared analyzer).

Important findings (1) The average carbon density (carbon stock per area) of Z. japonica warm tussock ecosystem in Yaoxiang small watershed was about 2.74 Mg C·hm-2 and the order of carbon density was as follows: soil carbon (89%) > vegetation carbon (9%) > litter carbon (2%), the total amount of carbon stock of warm tussock in Shandong Province was about 15.88 Tg C. (2) The NEE seasonal dynamics of Z. japonica warm tussock ecosystem was low in summer but high in winter. This ecosystem functioned as carbon source (i.e., CO2 emissions) during the non-growing seasons (October to March of next year), but acted as carbon sink (net absorption of CO2) during the growing seasons (April to September). The average carbon sequestration rate during the peak months was -2.58- -4.46 μmol CO2·m-2·s-1. The annual average NEE of small watershed warm tussock was respectively -0.43 and -0.31 μmol CO2·m-2·s-1 in the year of 2012 and 2013, indicating this ecosystem exhibited carbon sink effect. (3) The photosynthetic active radiation (PAR), atmospheric temperature (Ta), vapor pressure deficit (VPD) and the temperature and water content of 10 cm soil depth were the major factors regulating NEE dynamics in Z. japonica warm tussock ecosystem, but drivers of NEE dynamics in different months were different and had the interaction effects between factors. Principal component analysis indicated that the seasonal dynamics of NEE was mainly controlled by the temperature, moisture and light intensity.

Key words: warm-temperature tussock, Zoysia japonica, carbon pool, carbon sequestration status, carbon flux