摘要
采用网格法在帽儿山温带落叶阔叶林通量塔风浪区(1500 m×400 m)内设置直径为20 m的圆形样地106个,运用地统计学方法和回归分析法研究了乔木生物量空间格局及其驱动因子。结果表明,风浪区总生物量平均值为153.63 Mg/hm^2,变异系数为37.89%;根冠比平均0.25(变化范围0.18—0.36)。总生物量、地上生物量和地下生物量的空间自相关显著,半方差模型的结构比分别为0.50、0.61和0.50,空间异质性尺度分别为276 m、198 m和375 m。硬阔叶林与杂木林的生物量组分和根冠比差异均不显著,但以胸高断面积(BA)为协变量,生物量组分差异显著。硬阔叶林和杂木林生物量组分与BA均呈极显著的线性正相关关系,BA可以解释总生物量和地上生物量空间变异的85%以上,表明局域尺度上BA可作为森林乔木生物量的预测因子。两种林型的生物量与优势高呈对数线性关系,但相关程度较低(R^2<0.41)。杂木林的各生物量组分与坡度显著正相关,但硬阔叶林的关系不显著。帽儿山落叶阔叶林乔木生物量受BA、优势高、林型、坡度和坡向共同驱动而存在空间变异,因此在整合通量塔与地面碳汇测量时需要考虑空间异质性。
To cross-validate the accuracy of carbon flux estimates of the eddy covariance with that of the stand inventory method in temperate forests, we investigated the spatial variations in forest biomass and their driving factors within the fetch （ 1500 m × 400 m） of the Maoershan flux tower using a geostatistics approach and regression methods.One hundred and six circular plots with diameters of 20 m were established by a 100 m ×50 m grid using a total station. All of the trees with diameter at breast height （DBH） greater than 2 cm were measured in each plot. The biomass and its components were calculated based on the DBH data and the site-species-specific biomass equations developed previously. The ranges of the total, above-, and below-ground biomasses were 22.68-304.89, 17.99-245.96, and 4.69-69.25 Mg/hm2, respectively, with corresponding means of 155.64, 124.17, and 31.47 Mg/hm2. The root ： shoot ratio （RSR） ranged between 0.18 and 0.36, with a mean of 0.25. For the total biomass, the contribution of specific species was ranked in the following order： Ulmus japonica （ 22.80% ） 〉 Fraxinus mandshurica （ 15.70% ） 〉 Betula platyphylla （ 15.52% ） 〉 Betula costata （ 7.23% ） 〉 Juglans mandshurica （6.21%） 〉 Acer mono （6.20%）, with the remaining 26.34% contributed by other species （each〈 5%）. The coefficients of variation for the total, above-, and below-ground biomasses were 37.89%, 37.75%, 41.27%,respectively. The structural ratios of the semivariance functions for total, above- and below-ground biomasses were 0.50, 0.61, and 0.50, respectively, whereas the corresponding ranges were 276, 198, and 375 m. These data indicated a moderately significant spatial autocorrelation for the biomasses, whereas that for the RSR was week. The geostatistical mean of the total biomass density within the fetch of the flux tower （ 153.63 Mg/hm2） was close to the simple mean of the 106 plots, indicating the effective spatial representation of these plots. The biomass and RSR bet
出处
《生态学报》
CAS
CSCD
北大核心
2016年第20期6506-6519,共14页
Acta Ecologica Sinica
基金
国家"十二五"科技支撑项目(2011BAD37B01)
国家自然科学基金项目(41503071)
教育部长江学者和创新团队发展计划(IRT1054)
关键词
胸高断面积
森林生物量
根冠比
空间格局
温带落叶林
basal area
forest biomass
root
shoot ratio
spatial pattern
temperate deciduous forest
