Carbon concentration and carbon storage in different components of natural Quercus wutaishanica forest in Ziwuling of Loess Plateau, Northwest China

To accurately estimate the carbon storage and carbon density in Loess Plateau is of significance to understand the global carbon sink-source balance. In this study, an investigation was made on the carbon distribution in different components of natural Querus wutaishanica (syn. Q. liaotungensis) forest in Ziwuling of Loess Plateau hinterland, aimed to provide basis for accurately estimate the carbon concentration and carbon storage of forest vegetation in Loess Plateau. In the young and medium age, near-mature, and matured Q. wutaishanica forests, the carbon concentration of stem, bark, branch, leaf, and root was 44.16%-47.01%, 44.09%-45.50%, 43.17%-46.25%, 44.67%-46.36%, and 38.93%-41.10%, respectively. In shrub layer, the carbon concentration of leaf, branch, and root was 46.26%-44.39%, 30.19%-48.95%, and 28.06%-40.13%; in herb layer, the carbon concentration of above- and below-ground parts was 28.38%-45.27% and 24.53%-46.06%, respectively; and in litter layer, the carbon concentration was 32.10%-32.90%. The carbon storage of tree layer in the young and medium age, near-mature, and matured Q. wutaishanica forests was 32.78, 35.51, and 43.79 t·hm-2, and that of shrub layer, herb layer, and litter layer was 3.31, 1.72 and 0.87 t·hm-2, 0.32, 0.77 and 0.64 t·hm-2, and 6.03, 3.14 and 4.37 t·hm-2, respectively. The total carbon storage of the three age forests was 42.45, 41.41, and 49.67 t·hm-2, respectively. All the results indicated that in the Ziwuling of Loess Plateau hinterland, matured Q. wutaishanica forest had the greatest carbon storage, and in the three age natural Q. wutaishanica forests, the carbon storage was in the order of tree layer litter layer shrub layer herb layer. It was considered that in Ziwuling of Loess Plateau hinterland, the carbon storage of matured forest had the greatest contribution to the carbon storage of natural Q. wutaishanica forest, which should be paid more attention in the estimation of the carbon storage of natural Q. wutaishanica forest ecosystem in the study area in the future.