Analysis and application of the spatial distribution of forest carbon storage based on geographic code

This work aimed to explore the spatial distribution of forest carbon storage based on geographic code, to provide a method reference for the long-term spatial change analysis of forest carbon storage.

Based on the Second Survey data of Forest Resources of the Purple Mountain in 1987, 2002 and 2019, by taking advantage of the biomass conversion factor continuous function method and the geocoded fixed grid, the study analyzed the dynamics of forest carbon storage and its spatial distribution changes of the Purple Mountain in the past 32 years.

1) In terms of time dimension, the forest carbon storage in the study area in 1987, 2002 and 2019 were 62 541.1 t, 81 703.0 t and 106 281.8 t, respectively, with a net increase of 43 740.7 t and an average annual increase of 1 325.5 t in the past 32 years. The carbon storage of broad-leaved arbor forests accounted for 62.1%, 73.0% and 81.7% of the forest carbon storage, which was significantly greater than that of coniferous arbor forests and coniferous broad-leaved mixed arbor forests. Between 1987 and 2002, the sum of the carbon storage of middle-aged forests and mature forests accounted for 76.4% and 60.4% of that of arbor forests. In 2019, the carbon storage of mature and over-mature forests accounted for 59.5% of the total carbon storage of arbor forests. 2) In terms of spatial distribution, the forest carbon storage in the study area showed a gradually increasing spatial distribution from south to north. The regional proportion of medium carbon storage and high carbon storage increased from 45.1% in 1987 to 53.9% in 2002 and 60.3% in 2019. The stable, medium and high stability areas accounted for 71.1% of the study area, and generally, the stable area of forest carbon storage accounted for a relatively high proportion. 3) In terms of the role of forest management in the space-time dimension, in view of the difficulties in analyzing the long-term spatial change of regional forest carbon storage and the low accuracy of the clear spatial location of forest management, the method proposed in this paper can not only compare the distribution characteristics of forest carbon storage in the long-time series of the same spatial location but also compare and analyze the forest management effects of carbon sequestration and carbon increase in the specific spatial location, which is also convenient for query and supervision. Meanwhile, it can provide support for the long-term grid management of forest head systems and offer technical support for the accurate improvement of regional forest carbon sequestration management.

The spatial distribution of forest carbon storage has been studied by using the fixed grid of geocoding and the coefficient of variation index, which provides a reference for the sustainable monitoring of forest carbon storage in the Purple Mountain in the future.