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林业科学 ›› 2009, Vol. 12 ›› Issue (4): 1-6.doi: 10.11707/j.1001-7488.20090401

• 论文 •    下一篇

南亚热带7种林分凋落叶养分含量的年动态变化*

卢立华 蔡道雄 贾宏炎 何日明   

  1. (中国林业科学研究院热带林业实验中心 凭祥 532600)
  • 收稿日期:2008-08-28 修回日期:1900-01-01 出版日期:2009-04-25 发布日期:2009-04-25

Annual Variations of Nutrient Concentration of the Foliage Litters From Seven Stands in the Southern Subtropical Area

Lu Lihua,Cai Daoxiong,Jia Hongyan,He Riming   

  1. (The Experimental Center of Tropical Forestry, CAF Pingxiang 532600)
  • Received:2008-08-28 Revised:1900-01-01 Online:2009-04-25 Published:2009-04-25

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49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(14.44 g·kg-1,火力楠最低(5.11 g·kg-1); 次生林凋落叶P含量最高(1.20 g·kg-1),马尾松最低(仅0.53 g·kg-1); K也以次生林最高(5.16 g·kg-1),马尾松最低(1.71 g·kg-1); Ca以杉木最高(达11.10 g·kg-1),马尾松最低(仅3.76 g·kg-1);Mg以次生林最高(3.03 g·kg-1),马尾松最低(1.18 g·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。

关键词: 南亚热带, 林分凋落叶, 养分含量

Abstract:

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 standshad 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 trees 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 macelurei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 (11.10g·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.

Key words: southern subtropics, leaf litterfall, nutrient concentration