Forest soil CO(2) fluxes as a function of understory removal and N-fixing species addition
发表在:Journal of Enviromen 23(5) 949-957    于:2011
关键词:

soil CO2 fluxes; forest management practices; understory removal; N-fixing species addition; forest plantation

简介:

We report on the effects of forest management practices of understory removal and N-fixing species (Cassia alata) addition on soil CO2 fluxes in an Eucalyptus urophylla plantation (EUp), Acacia crassicarpa plantation (ACp), 10-species-mixed plantation (Tp), and 30-species-mixed plantation (THp) using the static chamber method in southern China. Four forest management treatments, including (1) understory removal (UR); (2) C. alata addition (CA); (3) understory removal and replacement with C. alata (UR+CA); and (4) control without any disturbances (CK), were applied in the above four forest plantations with three replications for each treatment. The results showed that soil CO2 fluxes rates remained at a high level during the rainy season (from April to September), followed by a rapid decrease after October reaching a minimum in February. Soil CO2 fluxes were significantly higher (P < 0.01) in EUp (132.6 mg/(m2·hr)) and ACp (139.8 mg/(m2·hr)) than in Tp (94.0 mg/(m2·hr)) and THp (102.9 mg/(m2·hr)). Soil CO2 fluxes in UR and CA were significantly higher (P < 0.01) among the four treatments, with values of 105.7, 120.4, 133.6 and 112.2 mg/(m2·hr) for UR+CA, UR, CA and CK, respectively. Soil CO2 fluxes were positively correlated with soil temperature (P < 0.01), soil moisture (P < 0.01), NO3 −-N (P < 0.05), and litterfall (P < 0.01), indicating that all these factors might be important controlling variables for soil C 2 fluxes. This study sheds some light on our understanding of soil CO2 flux dynamics in forest plantations under various management practices.

中国科学院
  • 版权所有:中国科学院华南植物园
  • 联系电话:020-37252862
  • 传真:020-37252862
  • 信箱:lizhen2011@scbg.ac.cn
  • 地址:广州市天河区兴科路723号
  • 邮编:510650