加勒比松林凋落物对地表径流和氮、磷流失的影响  

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

作　　者：薛立[1] 史小玲[1] 冯慧芳[1] 傅静丹[1] 郑卫国 田雪琴 

机构地区：[1]华南农业大学林学院,广州510642 [2]佛山市林业科学研究所,广东佛山528222

出　　处：《植物生态学报》2009年第5期878-884,共7页Chinese Journal of Plant Ecology

基　　金：广东省林业局资助项目(4400-F08018);佛山市科技资助项目(2005020061)

摘　　要：以佛山的加勒比松林(Pinus caribaea)为对象,研究了其地表径流及N和P流失量特点。结果表明,有凋落物加勒比松林和无凋落物加勒比松林的年径流量分别为12.6和51.8mm,其中夏季占90%以上。2种林分的地表径流量和降雨量的关系遵循线性方程。除2007年7月和2008年2月外,各月地表径流N浓度为有凋落物加勒比松林大于无凋落物加勒比松林,浓度的差异主要是因为年径流量不同引起的。总体来看,有凋落物加勒比松林的地表径流P浓度高,无凋落物加勒比松林低。地表径流N浓度与径流量之间存在着负指数关系。有凋落物加勒比松林和无凋落物加勒比松林的地表径流总N输出量分别为341和983g·hm–2,夏季分别占其年N流失量的73%和64%。无凋落物加勒比松林的地表径流P流失量高达21.5g·hm–2,而有凋落物加勒比松林为6.5g·hm–2。2008年6月为有凋落物加勒比松林和无凋落物加勒比松林的地表径流P流失高峰,分别占其年流失量的46%和60%。因此,保留林下凋落物可以降低加勒比松林的N和P的流失。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 nitro-gen 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.hm2, 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.

关 键 词：加勒比松 地表径流 氮流失 磷流失 

分 类 号：S714[农业科学—林学]