Estimation of carbon carrying capacity in the Yanhe River catchment of China's Loess Plateau

Estimation of carbon carrying capacity (CCC) can provide a reliable reference for the prediction of carbon sequestration potential by comparing it with the existent carbon stock, which is critical to the development of mitigation strategies and effective policies. The objectives of the present study were to approximate the CCC in a loess hilly region in China's Loess Plateau, analyse its change with bioclimatic gradients, and its validity as a reference for the prediction of carbon sequestration potential. With remnant secondary ecosystems as the basis, an environmental stratification sampling method was used to identify sample sites that covered most of the typical secondary communities in the Yanhe River catchment. Then a classification method was used to predict the above-ground CCC, and a generalized additive modelling approach was used to estimate the below-ground CCC in the Yanhe River catchment. The result showed that the above-ground CCC varied from 0.25 to 39.51 t ha(-1) across the catchment with an average of 4.12 +/- 9.26 t ha(-1), and the below-ground CCC (0-60 cm) varied from 14.73 to 182.99 t ha(-1) across the catchment with an average of 35.62 +/- 12.82 t ha(-1). If covered with natural secondary communities, the predicted total CCC of the catchment was 32.77x10(6) t, of which the above-ground stock accounted for 10% and below-ground stock accounted for 90%.This result may be valuable for accounting carbon stocks and fluxes and provide support for the development of improved management directions and landscape planning.