Distribution and altitudinal patterns of carbon and nitrogen storage in various forest ecosystems in the central Yunnan Plateau, China

Abstract

The carbon (C) pool in forest ecosystems plays a long-term and sustained role in mitigating the impacts of global warming, and the sequestration of C is closely linked to the nitrogen (N) cycle. Accurate estimates C and N storage (S _C, S _N) of forest can improve our understanding of C and N cycles and help develop sustainable forest management policies in the content of climate change. In this study, the S _C and S _N of various forest ecosystems dominated respectively by Castanopsis carlesii and Lithocarpus mairei (EB), Pinus yunnanensis (PY), Pinus armandii (PA), Keteleeria evelyniana (KE), and Quercus semecarpifolia (QS) in the central Yunnan Plateau of China, were estimated on the basis of a field inventory to determine the distribution and altitudinal patterns of S _C and S _N among various forest ecosystems. The results showed that (1) the forest S _C ranged from 179.58 ± 20.57 t hm ⁻¹ in QS to 365.89 ± 35.03 t hm ⁻¹ in EB. Soil, living biomass and litter contributed an average of 64.73%, 31.72% and 2.86% to forest S _C, respectively; (2) the forest S _N ranged from 4.47 ± 0.94 t ha ⁻¹ in PY to 8.91 ± 1.83 t ha ⁻¹ in PA. Soil, plants and litter contributed an average of 86.88%, 10.27% and 2.85% to forest S _N, respectively; (3) the forest S _C and S _N decreased apparently with increasing altitude. The result demonstrates that changes in forest types can strongly affect the forest S _C and S _N. This study provides baseline information for forestland managers regarding forest resource utilization and C management.