Chin J Plant Ecol ›› 2009, Vol. 33 ›› Issue (5): 878-884.DOI: 10.3773/j.issn.1005-264x.2009.05.006

• Research Articles • Previous Articles     Next Articles

EFFECTS OF LITTER IN PINUS CARIBAEA STANDS ON RUNOFF AND NITROGEN AND PHOSPHORUS LOSSES

XUE Li1,*(), SHI Xiao-Ling1, FENG Hui-Fang1, FU Jing-Dan1, ZHENG Wei-Guo1, TIAN Xue-Qin2   

  1. 1College of Forestry, South China Agricultural University, Guangzhou 510642, China
    2Foshan Institute of Forestry Science, Foshan, Guangdong 528222, China
  • Received:2009-02-10 Revised:2009-04-27 Online:2009-02-10 Published:2009-09-30
  • Contact: XUE Li

Abstract:

Aims Litter reduces surface runoff directly by an interception effect and indirectly by a barrier effect. Our objective is to study the effects of litter in Pinus caribaea stands on runoff and nitrogen and phosphorus losses by analyzing their runoff.
Methods We collected runoff from a P. caribaea stand with litter and a P. caribaea stand without litter in Foshan, Guandong Province and analyzed concentrations of nitrogen and phosphorus in the runoff in the lab.
Important findings Annual runoff amounts of the stands with and without litter were 12.6 and 51.8 mm, respectively, with >90% of annual runoff in summer. The relationships between rainfall and runoff in both stands were linear. Except for July 2007 and February 2008, monthly N concentration of the stand with litter was greater than the stand without litter, which was mainly caused by the difference in runoff amount between the two stands. Generally, monthly P concentration in the stand with litter was greater than that in the stand without litter. A negative exponent relationship existed between runoff and N concentration. Annual N losses of the stands with and without litter were 341 and 983 g·hm-2, respectively, accounting for 73% and 64% of their annual N losses, respectively. Annual P losses of the stands with and without litter were 6.5 and 21.5 g·hm-2, respectively. The greatest monthly P losses of the stands with litter and without litter occurred in June 2008, accounting 46% and 60% of their annual P losses, respectively. Therefore, N and P exports from P. caribaea stands could be significantly reduced by keeping litter in place.

Key words: Pinus caribaea, runoff, nitrogen loss, phosphorus loss