杉木及其混交林的结构与功能模型——以福建省将乐国有林场为例

Structure and function model of Chinese fir and its mixed-forest:A case study in Jiangle state-owned forest farm,Fujian Province

为提高森林多功能经营水平和森林效益,以福建省将乐国有林场内典型的杉木及其混交林为例,以17个易测因子为自变量,分别以森林生物量积累功能、水源涵养功能、保育土壤功能以及生物多样性保护功能为因变量,建立林分结构与功能的多元线性回归模型,并利用主成分分析法得到森林综合功能模型。结果表明:1)林分年龄、平均胸径和密度对森林的各项功能均具有一定的影响,林分平均高更侧重于影响森林的水源涵养功能。2)决定森林多功能水平的林分因子主要为林分年龄和林分平均胸径。3)在55块调查标准地中,森林综合功能指数最高为453,最低为-153。将乐国有林场82%的杉木林综合功能良好,18%的杉木林木材生产能力和多样性保护能力较弱,需针对这部分林分进行结构调整以提高森林的多功能性。

[ Background ] Due to the deterioration of ecological environment, forest service functions were getting more and more attention. Forest function is closely influenced by the structure. It has been the research focus that how to quantitative describe the relationship between forest structure and function. The purpose of this study is to define the quantitative relationship between Cunninghamia lanceolata forest stand structure and function through the multiple regression model, and then to improve the forest multi- function management level and forest benefits by adjusting iorest structure. [ Methods] C. lanceolata and its mixed-forest which is typical in Jiangle state-owned forest farm in Fujian Province were taken as an example. Seventeen easy measuring factors （stand age （A） , stand average diameter at breast height （DBH）, stand average height （ H）, stand density, maximum water holding capacity of litter, soil non- capillary water capacity, total P, total K, total N, organic matter content, tree layer biomass, shrub layer biomass, herb layer biomass, shrub richness, herb richness, shrub diversity, herb diversity） were chosen as independent variables （IV）, functions including forest biomass accumulation, water conservation, soil conservation and species diversity conservation were considered as dependent variables, then a forest structure and function model was built by multiple linear regression method, and a forest comprehensive function model was finally established by principal components analysis method. [ Results] The stand biomass per hectare was mainly determined by A, DBH and stand density （R^2 = 0. 801 4）. Water conservation function was mostly influenced by A, DBH, H and stand density （R^2 = 0. 561 2）. Soil conservation function was mainly affected by A, DBH and H （R^2 =0. 561 2）. Richness and diversity of undergrowth were determined by A, DBH, H and stand density （ R^2 = 0. 661 8）. Factors including A, DBH and stand density had influences on all of the studied forest functions, while stand average height had a significant effect on forest water conservation function. In the forest comprehensive function model, first five principal components, respectively, reflected the forest timber production function, species diversity conservation function, soil conservation function, biomass accumulation function and water conservation function. Among the 55 sample plots, the highest forest comprehensive function index （Fj） was 453 （No. 19） while the lowest was -153 （No. 5）. Sample plot No. 19 had a significantly higher index in A, DNH, H and tree layer biomass than No. 5. [ Conclusions ] Forest multi-function was mainly determined by stand age and average DBH. 82% of Chinese fir forest had a powerful forest comprehensive function, however, 18% of Chinese fir forest had a weak timber production capacity and diversity protection ability, which needs forest stand structural adjustment to raise its＇ forest multi-function level.