[Objective] Based on data obtained from a survey of sample plots of 26-year-old major shrub plantations,carbon density and their distribution patterns were analyzed,aiming at providing the basic data for estimation of carbon benefits of the plantations in Loess Plateau in south Ningxia.[Method] Based on shrub layer biomass,herb layer biomass,soil samples from 0-100 cm layers of plots,carbon density and its variation of each component of H.rhamnoides,C.korshinskii and P.davidiana shrub plantations in afforestation area of Longde country,Ningxia were quantified.[Result] The results showed that forest carbon density of Hippophae rhamnoides,Caragana korshinskii and Prunus davidiana were 56.30,74.20 and 117.44 t/hm2,respectively,the carbon density spatial distribution pattern was consistent,namely the carbon density of soil layer accounted for the largest proportion,respectively 84.10％,74.49％ and 84.82％;followed by the shrub layer,the proportion was 15.03％,25.15％ and 15％;the smallest proportion of herbaceous layer were 0.78％,0.36％ and 0.17％.0-10 cm soil layer carbon densities of Hippophae rhamnoides,Caragana korshinskii,and Prunus davidiana were 1.84,2.50 and 3.48 times that of 50-100 cm soil layer,respectively.[Conclusion] Shrub layer is the majority of vegetation carbon density.Carbon density in soil layer decreased with soil depth increasing.Soil carbon pool is the majority of forest carbon density.%[目的]基于宁南黄土丘陵区26年生主要人工灌木林样地调查数据,分析林地碳密度及其分配规律,以期为该地区人工灌木林碳效益估算提供基础数据.[方法]在宁夏隆德县退耕还林实施区,选择26年生沙棘(Hippophae rhamnoides)、柠条(Caragana korshinskii)和山毛桃(Prunus davidiana)灌木林设置样地,测算灌木层、草本层的生物量,并取0～ 100 cm土层土样,测定不同土层土壤体积质量,计算灌木层、草本层和土壤层的碳密度,分析3种灌木林各组分及土壤碳密度的变化.[结果]沙棘、柠条、山毛桃林地碳密度分别为56.30、74.20和117.44 t/hm2,其碳密度的空间分布格局基本一致,即土壤层碳密度所占比例最大,分别占84.10％、74.49％和84.82％;其次为灌木层,所占比例分别为15.03％、25.15％和15.00％;草本层所占比例最小,分别为0.78％、0.36％和0.17％.沙棘、柠条和山毛桃0～10 cm土层碳密度分别为50～100 cm土层碳密度的1.84、2.50和3.48倍.[结论]灌木层是植被碳密度的主体;土壤碳密度随土层深度的增加而下降;土壤碳库是林地碳密度的主体.
展开▼
