Estimating Carbon Sequestration Potential of Forest and Its Influencing Factors at Fine Spatial-Scales: A Case Study of Lushan City in Southern China

Abstract

Accurate prediction of forest carbon sequestration potential requires a comprehensive understanding of tree growth relationships. However, the studies for estimating carbon sequestration potential concerning tree growth relationships at fine spatial-scales have been limited. In this paper, we assessed the current carbon stock and predicted sequestration potential of Lushan City, where a region has rich vegetation types in southern China, by introducing parameters of diameter at breast height (DBH) and tree height in the method of coupling biomass expansion factor (BEF) and tree growth equation. The partial least squares regression (PLSR) was used to explore the role of combined condition factors (e.g., site, stand, climate) on carbon sequestration potential. The results showed that (1) in 2019, the total carbon stock of trees in Lushan City was 9.22 × 105 t, and the overall spatial distribution exhibited a decreasing tendency from northwest to south-central, and the carbon density increased with elevation; (2) By 2070, the carbon density of forest in Lushan City will reach a relatively stable state, and the carbon stock will continue to rise to 2.15 × 106 t, which is 2.33 times of the current level, indicating that Lushan forest will continue to serve as a carbon sink for the next fifty years; (3) Excluding the effect of tree growth, regional forest carbon sequestration potential was significantly influenced on site characteristics, which achieved the highest Variable Importance in Projection (VIP) value (2.19) for slope direction. Our study provided a better understanding of the relationships between forest growth and carbon sequestration potential at fine spatial-scales. The results regarding the condition factors and how their combination characteristics affect the potential for carbon sequestration could provide crucial insights for Chinese carbon policy and global carbon neutrality goals.

Differentiation of Carbon Sink Enhancement Potential in the Beijing–Tianjin–Hebei Region of China

“…Additionally, the carbon sink per unit land area of the forest varied along with the change in the age of stand [42], which was not considered in this study. In particular, there is a large amount of planted or secondary forest with considerable carbon sink potential after decades of reforestation in the northwest and northern parts of the study area [43,44], but there has been limited research on the carbon sink potential concerning tree growth relationships at fine spatial scales [45]. It is therefore necessary to carry out more in-depth research on changes in carbon sink per unit land area over time based on dynamic carbon sink coefficients and accurate vegetation types by integrating the data of vegetation types, crop types, and forest growth data so as to provide a better understanding of carbon sink enhancement potential in the future [34].…”

The Estimation of Forest Carbon Sink Potential and Influencing Factors in Huangshan National Forest Park in China

“…The pathways of influence also differ between species; for example, the carbon sink potentials of Quercus and C. sclerophylla are directly affected by crown density, soil thickness, and forest age, whereas that of P. taiwanensis is directly influenced by the slope position, altitude, soil thickness, and age. Unlike previous studies focused on small areas, some research [20,52] has found that site factors such as slope gradient and aspect are positively correlated with carbon sink potential because the direction and degree of slopes can redistribute light, heat, and water resources on the surface, affecting the forest's carbon sink process. However, when refining the study of influencing factors to different tree species, environmental factors can have various impacts on the carbon sink potential due to the different growth environment preferences of species; for example, P. taiwanensis commonly grows in high mountain areas, whereas C. sclerophylla prefers lower altitudes.…”

“…Huangshan National Forest Park (HNFP) serves as a successful case of forest conservation in China, where, under governmental management, it has been well protected with minimal human interference, offering an excellent opportunity to study the impact of geographic factors on a forest carbon sink. Furthermore, diverging from the traditional approach of evaluating the carbon sink potential based on forest types [20,21], research at the species scale aligns more closely with the characteristics of afforestation in smaller areas (which involve specific tree species). This research methodology and its findings are better suited to the precise management of regional afforestation efforts.…”

“…Considering the growth process of trees, the increase in the forest carbon stock in forest ecosystems is mainly caused by the increase in tree carbon density with the increase in age; ecologists believe that the changes in tree carbon density and age are closely related [30], and it is generally believed that the change in tree carbon density with age is consistent with the logistic, Richard-Chapman, and Gompertz growth functions, among others [31]. Studies have used tree age to calculate the carbon density of trees to obtain the carbon sink potential of forests in both large areas [9,21] and small areas [20,32]. Due to differences in the growth rates and conditions of different tree species, to obtain more accurate carbon stocks in forest ecosystems, different growth functions for different tree species can improve the accuracy of forest ecosystem carbon stocks, and thus improve the accuracy of carbon sink calculations.…”

Estimating Forest Stock Volume Based on Airborne Lidar Data

“…Forests are the mainstay of terrestrial ecosystems, their annual carbon sequestration accounts for about 2/3 of the entire terrestrial ecosystem (Post et al 1982;He et al 2022). They play an irreplaceable role in regulating global carbon balance, mitigating the greenhouse effect and tackling climate warming (Doelman et al 2019).…”