作　　者： ; ; ; ; ; (许松葵）;

机构地区： 华南农业大学林学院

出　　处： 《生态学报》 2010年第20期5466-5474,共9页

摘　　要： 2008年初,在波及我国南方大部分地区的雨雪冰冻灾害中,冻雨在杉木枝叶上形成冰柱,造成大量的杉木个体折冠。通过开展杉木林凋落物和树干残体的养分及土壤理化性质的研究,可以了解冰雪灾害后杉木林的土壤肥力动态。冰雪灾害造成的林冠折损引起了林地的光照增强,导致了土壤温度上升及土壤水分增加,从而促进了凋落物的分解,凋落物经过1a的分解后,N、P和K含量分别下降了7%、12%和21%。凋落物储量减少了22%,N、P和K的储量分别下降了27%、31%和38%。2009年树干残体的N和P含量分别上升5%和6%,而K含量降低15%。树干残体由于分解缓慢,其储量下降3%,N储量增加了2%,P储量不变,而K储量下降了18%。冰雪灾害后森林凋落物积累于地表,分解后形成较厚的有机质层,土壤结构因此变得疏松。2009年的土壤容重和毛管孔隙度减小,总空隙度和毛管持水量增加,非毛管孔隙显著增加。林冠残体在分解过程中促进了土壤有机质和养分的积累。2009年的土壤pH降低,有机质、全N、全P和全K含量分别增加了16%、11%、14%和8%,碱解N和速效P含量分别增加了113%和17%,而速效K含量下降了36%。 Early in 2008,a frozen rain and snow weather spreading over most parts of south China caused a big disaster.Icicles were produced on branches and leave of Cunninghamia lanceolata trees by sleets,resulting in that many live trees were damaged by crown breaking.The crown breaking coming from ice-snow damage caused an increase in solar radiation,which promoted litter decomposition by increasing soil temperature and water.The objective of this study is to assess the effect of the ice-snow damage on litter nutrients and nutrients of woody debris as well as soil physical and chemical properties.In comparing with those one year ago,N,P and K contents of litter decreased by 7%,12% and 21%,respectively,litter amount decreased by 22%.As a result,N,P and K amounts of litter decreased by 27%,31% and 38%,respectively.In 2009,N and P contents of woody debris increased by 5% and 6%,respectively,whereas K content decreased by 15%.Woody debris amount decreased by 3% due to its slow decomposing,and its N amount increased by 2%,P amount remained constant,whereas K decreased by 18%.Litter accumulated on ground after ice-snow damage,which caused a thick organic matter layer after litter decomposition,so that the soil became porous.Soil bulk density and capillary porosity of soil decreased,total porosity and capillary moisture capacity increased and non-capillary porosity significantly increased in 2009.Accumulations of soil organic matter and nutrients were accelerated during litter and stem debris decomposition.The pH value of soil decreased in 2009,contents of soil organic matter,total N,total P and total K increased by 16%,11%,14% and 8%,respectively,and alkalized N and available P increased by 113% and 17%,respectively,whereas available K decreased by 36%.

关 键 词： 杉木 冰雪灾害 凋落物 树干残体 土壤物理性质 土壤养分

领　　域： [农业科学] [农业科学]