为研究凋落量、组成和动态变化及其与气候因子间的关系,对福建沙县杉木人工林进行了连续7 a的定位观测。结果表明,2005-2011年杉木凋落量变化范围为1 051.83-2 407.80 kg.hm-2,年平均值为1 493.14 kg.hm-2,凋落量2005-2006年显著降低(P〈0.05),随后6 a间呈先增加再降低又增加的趋势,但变化幅度较为缓和。凋落物中落叶、落枝、落果、树皮及碎屑所占比例分别为62.9%、16.6%、7.63%、3.16%和9.73%。杉木凋落量季节动态总体表现为双峰型,峰值分别出现在2月(全年最大值)和7月,且2-7月凋落量占全年的62.3%,是杉木全年凋落量的主要贡献期。对凋落物的逐月观测数据与相应气象因子进行相关分析(Pearson和Spearman相关系数,n=84),结果显示,杉木凋落量对降水量和风速最为敏感(P〈0.05),其次是气温和日照时间。
In order to investigate the relationships between litterfall(production,composition and dynamics) and climatic factors,a 7-year-long field experiment was conducted in a Cunninghamia lanceolata(Lamb.) Hook.plantation in Shaxian,Fujian Province.Results showed that the ranges of litterfall production from 2005 to 2011 were from 1 051.83-2 407.80 kg · hm-2,with the mean value of 1 493.14 kg · hm-2 · y-1.Litterfall production reduced significantly from 2005 to 2006,while in the next 6 years,litterfall production increased followed by decreasing,and increased again finally,but its change scope was smooth.The litterfall proportions of leaves,branches,fruits,barks,rags were 62.9%、16.6%、7.63%、3.16% and 9.73%,respectively.The monthly dynamics of litterfall production showed a type of two peaks,which appeared in February(maximum) and July,accounting for 62.3% of the total annual production.The relationships between litterfall production and meteorological factors were examined by using Pearson and Spearman methods.The results showed that precipitation and wind speed were the most sensitive factors in C.lanceolataplantations(P0.05),followed by the temperature and sunshine hours.