科尔沁沙地南缘小叶锦鸡儿和黄柳灌丛生态系统碳汇动态研究

摘要

To understand the carbon sequestration of theCaragana microphylla andSalix gordejevii shrub ecosystem in the southern edge of Horqin Sandland, we choose theCaragana microphylla andSalix gordejevii shrub ecosystem plantation both of nine forest age sequences from the Aohanqi wind-sand region of Chifeng City as the study target. We use the Space for Time sample land approach to quantify the carbon density change rule of these two types of bush wood plantation in the level of shrub layer, herb layer, litter layer, soil layer and the ecosystem, analyze the carbon density and the annual carbon density change trend of shrub ecosystems with different planting years and make the equation for the planting years, carbon density and annual carbon sequestration rate. The results showed that: The carbon density for the shrub layer, herb layer, litter layer and the soil layer of theCaragana microphylla and Salix gordejevii increases as the planting years; the carbon density for each layer: the soil layer is the biggest, accounting for 60% and 75% of the ecosystem’s carbon density respectively; followed by carbon density of the shrub layer, accounting for 23% and 38% of the ecosystem’s carbon density respectively; the carbon density of the herb layer and the litter layer are minimum, both accounting for 1% of the ecosystem’s carbon density; The shrub layer carbon densities in various organs are branch > root > leaf, the herb layer carbon density in various organs are ground > underground; the carbon density changes of two shrubs over time could be expressed in log functions, the annual carbon sink rate for the ecology could be expressed by the power formula, when the planting years <10a, the annual carbon sink rate has a rapid growth, when the planting years > 10 a, the annual carbon sink rate declines. Our study suggests that the carbon density for theCaragana microphylla andSalix gordejevii shrub groups has obvious variation rules with certain carbon sink potentialities; when the planting years < 10a, the annual carbon sink rate has a rapid growth; with the growth of the planting years, the annual carbon sink rate declines, and it’s suggested to make effective forest management and tending measures on the forests and shrubs.%为了解科尔沁沙地南缘小叶锦鸡儿（Caragana microphylla）和黄柳（Salix gordejevii）灌丛生态系统的固碳功能，在赤峰市敖汉旗风沙土区分别选择9个林龄序列的小叶锦鸡儿和9个林龄序列的黄柳典型灌丛人工林为研究对象。利用空间代替时间样地测量法来量化两种灌丛人工林灌木层、草本层、凋落物层、土壤层和生态系统的碳密度变化规律，分析了不同林龄灌丛生态系统碳密度和年碳汇速率的变化趋势，并拟合了林龄与碳密度和年碳汇速率方程。结果表明：小叶锦鸡儿和黄柳两种灌丛林灌木层、草本层、凋落物层、土壤层碳密度均随林龄的增加而增大；各层碳密度大小为：土壤层碳密度最大，分别占生态系统碳密度的60%和75%，灌木层碳密度次之，分别占生态系统碳密度的23%和38%，草本层、凋落物层碳密度最小，均占生态系统碳密度的1%左右；灌木层各器官碳密度均为枝>根>叶，草本层各器官碳密度均为地上部分>地下部分；两种灌丛林的碳密度随时间的变化可用对数函数表述，生态系统年碳汇速率的变化可用乘幂式方程表述，林龄<10 a时，年碳汇速率增长迅速，>10 a时，年碳汇速率呈下降趋势。研究认为小叶锦鸡儿和黄柳灌丛群落碳密度随林龄增加的变化规律明显，具有一定的碳汇潜力；林龄<10 a时为年碳汇速率增长迅速期，随着林龄的增加，年碳汇速率有下降的趋势，需对灌丛林进行有效的抚育管理。