摘要
2006-05—2007-04对广西凭祥市7种主要林分凋落叶的N,P,K,Ca及Mg含量进行分析。结果表明:林分凋落叶的N,P,K,Ca及Mg含量全年月份动态变化趋势较为一致;在林木生长旺盛的高温雨季4—9月,林分凋落叶的N及P养分含量较高,而K的含量较低;在林木生长缓慢或休眠的干旱低温季10月至翌年3月,凋落叶N及P养分的含量较低,而K的含量较高,说明林分凋落叶的N与P含量与林木生长量成正相关,而K与生长量成负相关;Ca随月份的变化较小,但不同林分之间的差异较大;Mg随月份的变化较大;西南桦凋落叶N含量最高(14.44g·kg-1),火力楠最低(5.11g·kg-1);次生林凋落叶P含量最高(1.20g·kg-1),马尾松最低(仅0.53g·kg-1);K也以次生林最高(5.16g·kg-1),马尾松最低(1.71g·kg-1);Ca以杉木最高(达11.10g·kg-1),马尾松最低(仅3.76g·kg-1);Mg以次生林最高(3.03g·kg-1),马尾松最低(1.18g·kg-1);7种林分凋落叶的N,P,K,Ca与Mg的最高与最低含量比值都超过2。
To study the monthly dynamics of forest leaf litterfall, the leaf litters of 7 forests in Pingxiang of Guangxi were collected and their chemical components (N, P, K, Ca and Mg) were determined during the period from May of 2006 to April of 2007. The results indicated that the monthly variations of leaf litter' s nutrient contents of N, P, K, Ca and Mg in leaf litters from seven stands had common trends. The contents of N and P in the leaf litterfall were high, while the content of K was low in the rain season (from April to September) when the temperature was high and trees grew vigorously. By contrast in the dry season (from October to next March) when the temperature was low and trees grew slowly or was in dormancy, the concentration of K was high, and the contents of N and P were low in the leaf litterfall. It suggested that N and P concentrations in the leaf litterfall were positively related to growth of tree, whereas the concentration of K in foliage litter was negatively related with the tree's growth. The content of Ca was stable all the year within a forest, however it varied significantly from one stand to another. The monthly variation of Mg in leaf litterfall fluctuated significantly. The leaf litterfall' s nutrient contents of different forests varied greatly. The highest content of N ( 14.44 g·kg^-1 ) occurred in Betula alnoides plantation and the lowest N (5.11 g·kg^-1 ) in Michelia raacelurei plantation, the highest P (1.20 g·kg^-1) in the secondary natural forest and the lowest P (0.53 g·kg^-1) in Pinus massoniana plantation. Like to P, the highest of K was in the secondary natural forest with 5.16 g·kg^-1 and the lowest in Pinus massoniana plantation with 1.71 g·kg^-1 Ca of leaf litterfall in Cunninghamia lanceolata plantation was the highest ( 11.10 g·kg^-1 ), and that in Pinus massoniana plantation was the lowest with 3.76 g·kg^-1. Mg of leaf litter fall in the secondary natural forest was 3.03 g·kg^-1 (highest), and that in Pinus massoniana plantation was 1.18 g·kg^-1 (lowest). Among the 7 experimental forests, the ratio of the highest content to the lowest content of every nutrient in the leaf litterfall was more than two.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2009年第4期1-6,共6页
Scientia Silvae Sinicae
基金
国家十一五科技支撑"天然林保育恢复与可持续经营技术研究"课题(2006BAD03A04)之"天然次生林生态恢复与定向经营技术研究"专题(2006BAD03A0402)项目
关键词
南亚热带
林分凋落叶
养分含量
southern subtropics
leaf litterfall
nutrient concentration