Influence of stand density on soil CO2 efflux for a Pinus densiflora forest in Korea

Abstract

We investigated the influence of stand density [938 tree ha(-1) for high stand density (HD), 600 tree ha(-1) for medium stand density (MD), and 375 tree ha(-1) for low stand density (LD)] on soil CO(2) efflux (R (S)) in a 70-year-old natural Pinus densiflora S. et Z. forest in central Korea. Concurrent with R (S) measurements, we measured litterfall, total belowground carbon allocation (TBCA), leaf area index (LAI), soil temperature (ST), soil water content (SWC), and soil nitrogen (N) concentration over a 2-year period. The R (S) (t C ha(-1) year(-1)) and leaf litterfall (t C ha(-1) year(-1)) values varied with stand density: 6.21 and 2.03 for HD, 7.45 and 2.37 for MD, and 6.96 and 2.23 for LD, respectively. In addition, R (S) was correlated with ST (R (2) = 0.77-0.80, P < 0.001) and SWC (R (2) = 0.31-0.35, P < 0.001). It appeared that stand density influenced R (S) via changes in leaf litterfall, LAI and SWC. Leaf litterfall (R (2) = 0.71), TBCA (R (2) = 0.64-0.87), and total soil N contents in 2007 (R (2) = 0.94) explained a significant amount of the variance in R (S) (P < 0.01). The current study showed that stand density is one of the key factors influencing R (S) due to the changing biophysical and environmental factors in P. densiflora.

Soil Nitrogen Transformations and Availability in Upland Pine and Bottomland Alder Forests

“…The forests were sheltered from disturbances during the first half of the 20th century, in which the rule of Japanese Imperialism and the Korean War (1950)(1951)(1952)(1953) severely degraded nation-wide forests. The forests could provide reference status of the upland and bottomland forests in Korea, accompanied with abundant previous studies [25,[39][40][41][42]. Table 1.…”

“…Numbers in parentheses indicate the standard error of the means. Climate data was obtained from the nearest meteorological stations and site description data was taken from previous studies of the UPF [39,41] and BAF [25,42]. The sites are only 35 km apart and at the sites, precipitation was similar (Table 1).…”

“…Moreover, the UPF and the BAF would be determined as moderately fertile (medium) and N-rich (high) conditions, respectively, based on the needle or leaf litter and soil C:N ratio, and total N (sum of organic and inorganic N) storage in vegetation and soil, using the nutrient availability criteria by Vicca et al [43]. UPF stands were classified by stand density and BAF stands were classified by soil moisture, in order to characterize the spatial variability of stand structure and ecological processes in each type of forest (for UPF see [39,41] and for BAF see [25,42]). Stand density and soil hydrology are assumed to be the main environmental driver of upland forest and bottomland ecosystems, respectively; this assumption is generally applied to ecosystem management practices in each ecosystem.…”

Seasonal Variations of Soil CO2Efflux Rates and Soil Environmental Factors in Pinus densiflora and Quercus variabilis Stands

“…이와 같이 굴참나무 임분의 Q 10 값이 높은 것은 토양 pH가 높 은 굴참나무 임분이 소나무 임분에 비해 토양호흡에 관 계되는 미생물이나 뿌리 활력의 차이가 영향을 미치고 있기 때문으로 사료된다. 국내에서 수행된 소나무 임분 의 Q 10 값 2.9∼3.5 (Noh et al, 2010;Kim et al, 2012;Choi et al, 2015) (Kim et al, 2009a;Choi et al, 2016;Kim and Jeong, 2016). 토양 수분함량의 경우, (Kim et al, 2009a;Choi et al, 2016;Kim and Jeong, 2016).…”

Annual Variation of Soil CO2Efflux in a Broadleaved Deciduous Forest of the Geumsan (Mt.) Long-Term Ecological Research Site

“…However, soil CO 2 efflux can vary annually because the rates respond differently to changing environmental variables such as nutrient availability, soil water content, and soil temperature (Davidson et al, 1998;Raich and Tufekcioglu, 2000;Samuelson et al, 2009;Noh et al, 2010). Long-Term Ecological Research (LTER) program in forest ecosystems is designed to understand the structure and function of forest ecosystems by long-term monitoring.…”