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林业科学 ›› 2005, Vol. 41 ›› Issue (6): 7-15.doi: 10.11707/j.1001-7488.20050602

• 论文及研究报告 • 上一篇    下一篇

马尾松林下补植阔叶树后森林凋落物量、养分含量及周转时间的变化

林德喜 樊后保   

  1. 福建农林大学,福州350002
  • 收稿日期:2004-05-25 修回日期:1900-01-01 出版日期:2005-11-25 发布日期:2005-11-25

Changes in Amount, Nutrient Contents and Turnover Time of Forest Litter after Interplanting Hardwood Species Under Masson Pine Stand

Lin Dexi,Fan Houbao   

  1. Fujian Agriculture and Forestry University Fuzhou 350002
  • Received:2004-05-25 Revised:1900-01-01 Online:2005-11-25 Published:2005-11-25

摘要:

在25年生的马尾松林下分别补植拉氏栲、青栲、闽粤栲、格氏栲和苦槠,形成针阔混交异龄林。补植16年后,对上述5种混交林类型及马尾松纯林的森林凋落物量、养分含量及周转时间进行研究。上述5个混交群落和马尾松纯林的年凋落物量分别为6149.1、7533.2、6741.1、7151.5、8041.7和3442.8kg·hm-2。各混交群落总凋落物量的季节动态呈双峰型,第1次峰值出现在2—4月份,第2次峰值出现在8、9月份。在凋落物组成中,枯叶占绝对优势,占凋落物总量的50%~71%,其余依次为枯枝6%~26%、树皮9%~19%、果实和其他组分5%~17%。各混交群落中来自马尾松的凋落物占50%~58%,来自阔叶树的凋落物占42%~50%,且两者的组成有明显差异。凋落物各组分的养分含量存在较大差异,N、P、K、Ca、Mg的含量范围分别为3.25~12.98、0.24~0.97、0.37~6.55、12.77~35.40、2.35~6.10g·kg-1。各林分类型凋落物中养分元素的年归还总量为Ca>N>Mg>K>P。5个混交林群落及马尾松纯林凋落物中的养分年归还总量分别为238.05、213.77、223.93、289.90、304.12和142.01kg·hm-2。6个群落的森林地被物现存量分别为8448.0、15565.8、11993.7、12718.6、6974.2和5020.0kg·hm-2,其中L层在各群落中所占比例分别为47.2%、59.6%、51.3%、61.0%、85.4%及86·3%,平均为61.7%。森林地被物中各养分元素的含量在群落和组分之间存在明显差异,但总的趋势表现为Ca>N>Mg>K>P。最后,通过对年凋落量和林地凋落物积累量的比较分析,上述6个群落的凋落物周转时间预测值依次为0.76、1.42、0.97、1.17、0.84及1.52年,其中枯枝的周转时间明显大于枯叶,且马尾松的枯叶和枯枝的周转时间普遍大于阔叶树。

关键词: 马尾松-阔叶树混交林, 森林凋落物, 森林地被物, 养分含量, 凋落物周转时间

Abstract:

Seedlings of five hardwood tree species, Castanopsis lamontii, Cyclobalanopsis myrsinaefolia, Castanopsis fissa, Castanopsis kawakamii, and Castanopsis sclerophylla were separately planted under 25-year-old Masson Pine plantation. After sixteen years following planting, the amount, nutrient contents and turnover time of forest litter were investigated in the above five types of mixed uneven-aged stands and pure Masson Pine forest. Results revealed that annual litterfall in the five mixed stands were 6 149.1, 7 533.2, 6 741.1, 7 151.5 and 8 041.7 kg·hm-2 respectively, but only 3 442.8 kg·hm-2 in pure Masson Pine stand. Binomial patterns was found for seasonal dynamics of litter in the mixed stands. The first peak occurred from February to April, the second occurred in August or September. Leaves account for 50%~71% of the total litter, branches 6%~26%, barks 9%~19%, fruits about 1%, and other components 5%~17%. In the mixed stands, 50%~58% of the total litterfall came from Masson Pine trees, 42%~50% from the respective hardwood trees, with significant difference existing between their litter composition. Nutrient concentrations of litterfall were different, with N ranging from 3.25~12.98、0.37~6.55、0.24~0.97、12.77~35.40 and My to 2.35~6.10 g·kg-1. Total return of the five nutrient elements via litterfall for the six stands consistently decreased in the order: Ca>N>Mg>K>P. From annual litterfall the total return of five nutrient elements were 238.05, 213.77, 223.93, 289.90 and 304.12 kg·hm-2 respectively, for the five mixed communities, and 142.01 kg·hm-2 for pure Masson Pine stand. Litter accumulation in the forest floor in the five mixed stands were up to (8 448.0,) (15 565.8,) (11 993.7,) 12 718.6, and 6 974.2 kg·hm-2 respectively, and 5 020.0 kg·hm-2 for pure Masson Pine forest, with layer L making up of 47.2%, 59.6%, 51.3%, 61.0%, 85.4%, and 86.3% of the total respectively, averaged 61.7%. Significant differences in nutrient concentrations existed between forest communities and litter components, but the elements consistently revealed the same trend, decreasing in the order: Ca>N>Mg or K>P. Based on comparative analysis on litter accumulation and annual litterfall, the turnover time of litter in the six stands was estimated to be 1.15, 0.76, 1.42, 0.97, 1.17, 0.84 and 1.52 years respectively. Branches had longer turnover time than leafves. The branches and leaf from Masson Pine generally exhibited greater turnover time than that from the corresponding hardwood species interplanted under the pine canopy.

Key words: mixed forest of Masson Pine and hardwood, forest litter, forest floor, nutrient content, litter turnover time