模拟氮沉降对杉木人工林凋落物氮素含量及归还量的影响  

Effects of Simulated Nitrogen Deposition on Litterfall Nitrogen Concentrations and Its Annual Flux in Chinese fir Plantations

作　　者：樊后保[1] 黄玉梓[2] 裘秀群[3] 王强[4] 陈秋凤[2] 刘文飞[2] 徐雷[2] 

机构地区：[1]南昌工程学院,江西南昌330029 [2]福建农林大学,福建福州350002 [3]安徽工程科技学院,安徽芜湖241000 [4]萍乡高等专科学校,江西萍乡337055

出　　处：《江西农业大学学报》2007年第1期43-47,共5页Acta Agriculturae Universitatis Jiangxiensis

基　　金：国家自然科学基金资助项目(30370259);教育部留学回国人员科研启动基金资助项目;福建省自然科学基金重点资助项目(B0320001)

摘　　要：以亚热带杉木人工林为研究对象,开展4种水平的模拟氮沉降处理,分别为N0(对照)、N1(60kg/hm2.aN)、N2(120kg/hm2.a N)、N3(240kg/hm2.a N),每处理重复3次。通过对凋落物进行为期2年的监测后发现,氮沉降使落叶中的氮含量显著增加;凋落物其它组分中的氮含量对氮沉降的响应不敏感,处理之间没有显著差异。与对照(N0)相比,N2和N3处理分别使凋落物氮归还量增加10.9%和32.6%,而N1处理对氮归还量的影响不显著。氮素归还量还表现出一定的季节变化动态,虽各处理之间不尽相同,但总的来说,在2月份和5月份出现两个比较明显的峰值。A simulated nitrogen deposition experiment was conducted in Chinese fir plantations in the subtropical region in China. Treatments were designed as NO （0 kg/hm^2 ·a N）, Nl（60 kg/hm^2·a N）, N2 （120 kg/hm^2· a N） and N3 （240 kg/hm^2·a N）, with three replicates in each treatment. Based on two years of litterfall measurements, nitrogen deposition was found to significantly elevate nitrogen concentrations in fallen leaves, but nitrogen concentrations in other litterfall components （branches, fruits, barks and other droppings） displayed insensitive response to N deposition, no difference existed between the treatments. The annual nitrogen flux in litterfall responded positively to all N treatments, it had an increase of 32.6% in N3, 10.9% in N2,but no significant gain in N1, compared with the control （NO）. Seasonal dynamics of nitrogen flux in litterfall was different among the treatments, but generally showed two peaks occurring in February and May.

关 键 词：杉木人工林 氮沉降 森林凋落物 

分 类 号：S718.55[农业科学—林学]