龙里林场马尾松人工林凋落物养分归还动态

Dynamic of Nutrient Return from Litterfall in Pinus massoniana Plantation in Longli Forest Station

以贵州省龙里林场3个不同密度的12年生马尾松人工林为研究对象,通过调查测定凋落物归还量、养分归还量等指标,分析凋落物中N、P、K、Ca、Mg、Fe、Mn、Zn、Cu 9种养分的归还、转移、释放变化动态。结果表明:凋落物中9种养分年归还量与密度呈正相关,各林分平均养分年归还量从大到小为N、Ca、Mn、Mg、K、P、Fe、Zn、Cu;各林分养分月归还量变化趋势与月凋落物量变化趋势相似,除Zn为双峰型外其余为单峰型,峰值均出现在11月;马尾松人工林年凋落物量与密度呈正相关,S2167年凋落物量5 208.74 kg/(hm2·a),S1767年凋落物量4 284 kg/(hm2·a),S1200年凋落物量3 113.80 kg/(hm2·a);各林分月凋落物量变化趋势相似,均为单峰型,峰值出现在11月。

Experiments on nutrient retum were carried out in 12-year Pinus massoniana plantation with three densities in Longli Forest Farm, Guizhou province. Dynamic variation of return, transfer and release of N, P, K, Ca, Mg, Fe, Mn, Zn and Cu was analyzed b3 measuring return amount of litterfall and nutrient. The results indicated that annual return of nine nutrients had positive relation with density of plantation. Mean annual return amount of nutrient in different sample plots was ordered by N （22.22kg/ha）, Ca （21.46kg/ha）, Mn （8.034kg/ha）, K （5.94kg/ha）, P （5.34kg/ha）, Fe 1.90（kg/ha）, Zn （761.07g/ha）, Cu （318.30g/ha）. Monthly return amount of nutrient had similar change, topped in November, except Zn with ＂double peak＂. Annual litterfall amount had positive relation with density of plantation. Monthly litterfall amount had similar variation, topped in November.