广西不同气候条件下马尾松人工林生物量模型构建及分配格局

Biomass Model Construction and Distribution Pattern of Pinus massoniana Plantations under Different Climatic Conditions in Guangxi

关键词:  马尾松  人工林  生物量  分配格局  估测模型  气候条件

Key words:  Pinus massoniana  plantations  biomass  distribution pattern  estimation models  climatic conditions

摘要:

为科学地理解马尾松Pinus massoniana人工林地上生物量的分配格局及随气候带的变化，以广西中亚热带、南亚热带和北热带不同气候条件下马尾松人工林幼龄林、中龄林和过熟林为研究对象，构建生物量模型，并基于所得的模型比较分析不同气候条件下马尾松人工林生物量分配特征。结果表明：（1）灌木层立木生物量模型中，干和整株地上部分生物量的拟合效果较好，且模型Ⅱ：W=a×D^b×H^c的各项评价指标最好；（2）马尾松中龄林的群落及乔木层各部分生物量的积累均表现为南亚热带 > 北热带 > 中亚热带，灌木层的叶和枝生物量积累均表现为北热带 > 南亚热带 > 中亚热带，干和地上生物量均表现为南亚热带 > 中亚热带 > 北热带；幼龄林和过熟林（除叶生物量外）群落各部分生物量积累分别均为南亚热带最少；（3）中龄林叶生物量表现为南亚热带 > 北热带 > 中亚热带，枝、干和地上生物量均表现为北热带 > 南亚热带 > 中亚热带，马尾松各部分生物量（除叶生物量外）在群落中占比以及乔木层马尾松各部分生物量占比均表现为北热带 > 中亚热带 > 南亚热带。幼龄林和过熟林生物量积累分别均为南亚热带最少，马尾松各部分占比均为南亚热带最低。气候条件变化对马尾松不同阶段各部分均有着明显的影响，不同气候条件下马尾松生物量有明显不同。

Abstract:

In order to scientifically understand the distribution pattern of above-ground biomass of Pinus massoniana plantation and its changes with climatic zone,the young,middle-aged and over-mature forests of P.massoniana plantations under different climatic conditions in the mid-subtropical,southern subtropical and northern tropical regions of Guangxi were taken as the research objects,and a biomass model was built.Based on the obtained model,the biomass allocation characteristics of P.massoniana plantations under different climatic conditions were compared and analyzed.The results showed that:(1) In the shrub layer standing biomass models,the fitting effect of the above-ground biomass of the trunk and whole plants was better,and the model Ⅱ:W=a×D^b×H^c has the best evaluation index.(2) The community of middle-aged P.massoniana forest and the accumulation of biomass in various parts of the tree layer was shown as south subtropical > north tropical > middle subtropical.The accumulation of leaf and branch biomass in the shrub layer was shown as north tropical > southern subtropical > middle subtropical.The trunk and above-ground biomass are expressed as south subtropical > mid-subtropical > north tropical.The accumulation of biomass in each part of the community in young forests and over-mature forests (except leaf biomass) was the smallest in the southern subtropics.(3) The leaf biomass of P.massoniana of the middle-aged forest was shown as south subtropical > north tropical > mid-subtropical,and the biomass of branch,trunk and above-ground was all shown as north tropical > south subtropical > mid-subtropical.The biomass of all parts of P.massoniana (except leaf biomass) in the community and the biomass of each part of tree layer were expressed as north tropical > mid-subtropical > south subtropical.The biomass accumulation of young forests and over-mature forests was the least in southern subtropics,respectively,and the proportion of each part of P.massoniana was the lowest in southern subtropics.The change of climatic conditions had significant influence on different parts of P.massoniana at different stages,and the biomass of P.massoniana was obviously different under different climatic conditions.