Carbon cycling and net ecosystem production at an early stage of secondary succession in an abandoned coppice forest

Abstract

Secondary mixed forests are one of the dominant forest cover types in human-dominated temperate regions. However, our understanding of how secondary succession affects carbon cycling and carbon sequestration in these ecosystems is limited. We studied carbon cycling and net ecosystem production (NEP) over 4 years (2004-2008) in a cool-temperate deciduous forest at an early stage of secondary succession (18 years after clear-cutting). Net primary production of the 18-year-old forest in this study was 5.2 tC ha(-1 )year(-1), including below-ground coarse roots; this was partitioned into 2.5 tC ha(-1 )year(-1) biomass increment, 1.6 tC ha(-1 )year(-1) foliage litter, and 1.0 tC ha(-1 )year(-1) other woody detritus. The total amount of annual soil surface CO(2) efflux was 6.8 tC ha(-1 )year(-1), which included root respiration (1.9 tC ha(-1 )year(-1)) and heterotrophic respiration (RH) from soils (4.9 tC ha(-1 )year(-1)). The 18-year forest at this study site exhibited a great increase in biomass pool as a result of considerable total tree growth and low mortality of tree stems. In contrast, the soil organic matter (SOM) pool decreased markedly (-1.6 tC ha(-1 )year(-1)), although further study of below-ground detritus production and RH of SOM decomposition is needed. This young 18-year forest was a weak carbon sink (0.9 tC ha(-1 )year(-1)) at this stage of secondary succession. The NEP of this 18-year forest is likely to increase gradually because biomass increases with tree growth and with the improvement of the SOM pool through increasing litter and dead wood production with stand development.

Spatial Upscaling of Soil Respiration under a Complex Canopy Structure in an Old‐Growth Deciduous Forest, Central Japan

“…Temporal change in R s is primarily controlled by T s in many temperate deciduous forests [6][7][8]; R s generally increases with an exponential increase in T s within the range 0-25 • C. In concurrence with these previous investigations, the present study showed a pattern of increasing R s with increasing T s (Figure 7).…”

“…For evaluation of annual R s using equations, seasonal R s has often been estimated using only T s dependence as an exponential relationship in forests where W is not limiting (e.g., [6][7][8][43][44][45]). However, in forests where there is a drying period, R s has been estimated by the coupling of T s and W, although an empirical model using these variables has been unclear [3,31,[35][36][37][38][39].…”

“…The diurnal variation in R s is explained by plant physiology, especially photosynthesis [1], and soil temperature (T s ) [5]. The seasonal variation in R s is primarily controlled by T s when the soil water content (W) is not limited, and the response of R s to T s is usually explained by an exponential (Q 10 ) relationship [6][7][8].…”

Budget and distribution of organic carbon in Quercus serrata Thunb. ex Murray forest in Mt. Worak

“…In particular, there was a tree in this community damaged by wild animals in 2012 but it was recovering very fast. The uptake of organic carbon in this community seems to be higher than other communities as Ohtsuka et al (2010) states that the damage recovery is faster in younger forests which affects the production.…”

“…The reason why standing biomass, annual net production, and plant organic carbon show different values to other research is because forest age and tree density of different research sites have influenced the study. Kimmins (1987) stated that the standing biomass and net production increases with aging of the forest in case of young forests given that community structure of the forest is similar and Ohtsuka et al (2010) also reported that the increase of biomass and net production of younger forest is greater than the older forest. In addition, the NPP of forest ecosystem typically changes with the forest age, and it starts to decrease once dense pioneer community reaches its peak (Marks 1974, Smith and Long 2001, Binkley et al 2002.…”