The Effects of Tree Species on Soil Organic Carbon Content in South Korea

Abstract

The effects of tree species on soil organic carbon (SOC) content have been evaluated in many studies, but only with a relatively small number of sample plots, resulting in ambiguous conclusions. Here we used a total of 595 forest plots in South Korea to investigate the role of four grouped tree species—pines, oaks, other conifers, and other deciduous trees—in the forest SOC content in both forest floors and mineral soils. Significant differences were observed in SOC content among the groups. Pines contained 7.12 Mg C/ha of organic carbon in forest floors, whereas oaks and other deciduous trees contained 5.39 and 5.41 Mg C/ha, respectively. In contrast, oaks and other deciduous trees contained ~66 Mg C/ha of organic carbon each in mineral soils (0‐ to 30‐cm depth), whereas pines contained 49.50 Mg C/ha. The total SOC content including both forest floors and mineral soils was the largest under oaks and the smallest under other coniferous trees, due to SOC being approximately an order of magnitude higher in mineral soils than in forest floors. The effects of tree species on SOC storage became apparent for the forest stands with >20‐year‐old trees, which suggests that the observed differences in the SOC content are likely due to the current stands rather than remnants of previous stands. The decomposition rates of organic materials could be a controlling factor affecting SOC storage, rather than inputs of photosynthesized products to soils.

Do different land use changes in a deciduous forest ecosystem result in alterations in soil organic C and total N stocks?

“…First, the lack of significant differences in C:N ratios between the PRF sites (Table 3) indicates that the rate of SOC stock accumulation or release through organic matter decomposition and mineralization in both sites could be the similar. This is in line with studies in South Korea that illustrate that the rate of SOC storage in a study site is influenced by the soil C:N ratio (Cha et al 2019;Kim et al 2016). Second, the cultivation style of the paddy rice farm prior to reforestation or disturbances in the DNF might not have been enough to destabilize SOC and STN stocks.…”

Relative contribution of plant traits and soil properties to the functioning of a temperate forest ecosystem in the Indian Himalayas

“…Our results also indicated that above-ground species of tree is important for above-ground and soil organic C stocks, explaining 30% and 10% of variation, respectively. This is consistent with previous findings for aboveground biomass in a Pinus kesiya forest and soil organic C in pine, oak, conifer, and deciduous forests (Cha et al, 2019;Li et al, 2018). The importance of plant species for soil properties has been shown in several studies.…”

Soil aggregation accounts for the mineral soil organic carbon and nitrogen accrual in broadleaved forests as compared to that of coniferous forests in Northeast China: Cross‐sites and multiple species comparisons

“…Furthermore, large inter-site variations of soil properties (Boca et al, 2014;Wang et al, 2016) possibly obscure inter-species effects (Wang, Wang, & Chang, 2017). It is possible to compare broadleaf and conifer species by designing experiments within a single site (Cha, Cha, & Oh, 2019;Kooch, Rostayee, & Hosseini, 2016;Sariyildiz et al, 2015;Tang & Li, 2013), but when multiple-species were across large-scale sites, the site variations need to be statistically excluded.…”