Photosynthetic responses of Larix kaempferi and Pinus densiflora seedlings are affected by summer extreme heat rather than by extreme precipitation.

The frequency and intensity of summer extreme climate events are increasing over time, and have a substantial negative effect on plants, which may be evident in their impact on photosynthesis. Here, we examined the photosynthetic responses of Larix kaempferi and Pinus densiflora seedlings to extreme heat (+ 3 °C and + 6 °C), drought, and heavy rainfall by conducting an open-field multifactor experiment. Leaf gas exchange in L. kaempferi showed a decreasing trend under increasing temperature, showing a reduction in the stomatal conductance, transpiration rate, and net photosynthetic rate by 135.2%, 102.3%, and 24.8%, respectively, in the + 6 °C treatment compared to those in the control. In contrast, P. densiflora exhibited a peak function in the stomatal conductance and transpiration rate under + 3 °C treatment. Furthermore, both species exhibited increased total chlorophyll contents under extreme heat conditions. However, extreme precipitation had no marked effect on photosynthetic activities, given the overall favorable water availability for plants. These results indicate that while extreme heat generally reduces photosynthesis by triggering stomatal closure under high vapor pressure deficit, plants employ diverse stomatal strategies in response to increasing temperature, which vary among species. Our findings contribute to the understanding of mechanisms underlying the photosynthetic responses of conifer seedlings to summer extreme climate events.

Unraveling the ecological threads: How invasive alien plants influence soil carbon dynamics.

Invasive alien plants (IAPs) pose significant threats to native ecosystems and biodiversity worldwide. However, the understanding of their precise impact on soil carbon (C) dynamics in invaded ecosystems remains a crucial area of research. This review comprehensively explores the mechanisms through which IAPs influence soil C pools, fluxes, and C budgets, shedding light on their effects and broader consequences. Key mechanisms identified include changes in litter inputs, rates of organic matter decomposition, alterations in soil microbial communities, and shifts in nutrient cycling, all driving the impact of IAPs on soil C dynamics. These mechanisms affect soil C storage, turnover rates, and ecosystem functioning. Moreover, IAPs tend to increase gross primary productivity and net primary productivity leading to the alterations in fluxes and C budgets. The implications of IAP-induced alterations in soil C dynamics are significant and extend to plant-soil interactions, ecosystem structure, and biodiversity. Additionally, they have profound consequences for C sequestration, potentially impacting climate change mitigation. Restoring native plant communities, promoting soil health, and implementing species-specific management are essential measures to significantly mitigate the impacts of IAPs on soil C dynamics. Overall, understanding and mitigating the effects of IAPs on soil C storage, nutrient cycling, and related processes will contribute to the conservation of native biodiversity and complement global C neutrality efforts.

The complete chloroplast genome of an Arctic lycophyte, Huperzia arctica (Tolm.) Sipliv. 1973 (Lycopodiaceae).

Huperzia arctica (Tolm.) Sipliv. 1973 is a lycophyte species belonging to the Lycopodiaceae family, which is widely distributed in the Arctic region of Svalbard, Norway. To determine its taxonomic position, we sequenced the chloroplast genome of H. arctica. The complete chloroplast genome of H. arctica is 153,956 bp in length with 122 annotated genes, including 87 protein-coding genes, 31 tRNA genes, and 4 rRNA genes. To evaluate its evolutionary position, we performed phylogenetic analysis using 36 conserved orthologous protein-coding gene sequences from the chloroplast genomes of H. arctica and publicly available data from other Lycopodiaceae. H. arctica formed a monophyletic group with four other Huperzia species: H. lucidula, H. serrata, H. crispata, and H. javanica. However, it appeared as a separate species with a highly supported bootstrap value.

Tree size diversity is the major driver of aboveground carbon storage in dryland agroforestry parklands.

Despite the importance of agroforestry parkland systems for ecosystem and livelihood benefits, evidence on determinants of carbon storage in parklands remains scarce. Here, we assessed the direct and indirect influence of human management (selective harvesting of trees), abiotic factors (climate, topography, and soil) and multiple attributes of species diversity (taxonomic, functional, and structural) on aboveground carbon (AGC) stocks in 51 parklands in drylands of Benin. We used linear mixed-effects regressions and structural equation modeling to test the relative effects of these predictors on AGC stocks. We found that structural diversity (tree size diversity, HDBH) had the strongest (effect size ß = 0.59, R2 = 54%) relationship with AGC stocks, followed by community-weighted mean of maximum height (CWMMAXH). Taxonomic diversity had no significant direct relationship with AGC stocks but influenced the latter indirectly through its negative effect on CWMMAXH, reflecting the impact of species selection by farmers. Elevation and soil total organic carbon content positively influenced AGC stocks both directly and indirectly via HDBH. No significant association was found between AGC stocks and tree harvesting factor. Our results suggest the mass ratio, niche complementarity and environmental favorability as underlying mechanisms of AGC storage in the parklands. Our findings also highlight the potential role of human-driven filtering of local species pool in regulating the effect of biodiversity on AGC storage in the parklands. We conclude that the promotion of AGC stocks in parklands is dependent on protecting tree regeneration in addition to enhancing tree size diversity and managing tall-stature trees.

The toxicological effect on pak choi of co-exposure to degradable and non-degradable microplastics with oxytetracycline in the soil.

Microplastics and antibiotics are emerging as ubiquitous contaminants in farmland soil, harming crop quality and yield, and thus threatening global food security and human health. However, few studies have examined the individual and joint effects of degradable and/or non-degradable microplastics and antibiotics on crop plants. This study examined the individual and joint effects of polyethylene (PE) and polylactic acid (PLA) microplastics and the antibiotic oxytetracycline (OTC) on pak choi by measuring its growth, photosynthesis, antioxidant enzyme activity, and metabolite levels. Microplastics and/or oxytetracycline adversely affected root weight, photosynthesis, and antioxidant enzyme (superoxide dismutase, catalase, and ascorbate peroxidase) activities. The levels of leaf metabolites were significantly altered, causing physiological changes. Biosynthesis of plant secondary metabolites and amino acids was altered, and plant hormones pathways were disrupted. Separately and together, OTC, PE, and PLA exerted phytotoxic and antagonistic effects on pak choi. Separately and together with OTC, degradable microplastics altered the soil properties, thus causing more severe impacts on plant performance than non-degradable microplastics. This study elucidates the effects on crop plants of toxicity caused by co-exposure to degradable or non-degradable microplastic and antibiotics contamination and suggests mechanisms.

Multi-site assessment of soil nitrogen stocks across temperate forests under different thinning intensities, recovery times, and site conditions.

Increasing research interests have been paid to understand the factors controlling soil nitrogen (N) stocks under diverse environmental conditions and forest thinning regimes. This study investigated soil N stocks across 13 temperate forests, each of which received three thinning intensities (unthinned control, 15-30 %, and 30-50 % basal area removals) under varying pre-treatment conditions (altitude, slope, soil pH, soil moisture, stand age, stand density, diameter at breast height, and tree height). The total N stored in the forest floor (L, F, and H layers) and mineral soils (0-10, 10-20, and 20-30 cm) was determined 1, 4, and 7 years after thinning. Given the various site conditions and thinning regimes, a standardized effect size was used to analyze the influences of thinning on N stocks. The N stocks (Mg N ha-1) of the forest floor and at 0-10, 10-20, and 20-30 cm mineral soil depths were 0.02-0.46, 0.32-3.21, 0.29-3.03, and 0.25-2.54 across all studied forests, respectively. The averaged effect sizes indicated decrease in forest floor N stocks and increase in mineral soil N stocks under thinning due to the reduced litterfall and eventual input of thinning residues. Thinning intensity negatively affected the effect sizes for the N stocks (P < 0.05), suggesting that excessively heavy thinning may be inappropriate for retaining forest soil N. However, multimodel inference showed that soil pH (relative importance = 1.00) and stand age (relative importance = 0.42) had the largest influence on the effect sizes for forest floor and mineral soil N stocks. This pattern suggests that the effects of thinning on soil N stocks might vary with pre-treatment conditions, even more than thinning intensities and recovery time; therefore, thinning to manage forest soil N should consider pre-treatment environmental conditions in addition to thinning regime.

Understanding the Impact of the COVID-19 Pandemic on the Perception and Use of Urban Green Spaces in Korea.

Faced with the prospect that the impact of the COVID-19 pandemic and climate change will be far-reaching and long-term, the international community is showing interest in urban green space (UGS) and urban green infrastructure utilization as a solution. In this study, we investigated how citizens' perceptions and use of UGS have changed during COVID-19. We also collected their ideas on how UGS can raise its usability. As a result, more people became to realize the importance of UGS. In particular, the urban environmental purification function from UGS was recognized as giving great benefits to respondents. On the other hand, the patterns of UGS use were mixed with decreasing UGS use to maintain social distancing or increasing UGS use to maintain health or substitute other restricted facilities. More than half of respondents had their UGS visit patterns impacted by COVID-19. In particular, the increase rate of UGS use was rather high in the group that seldom used UGS before COVID-19. In addition, they increased the use of UGS to replace other limited facilities, and thus tended to demand an increase in rest facilities. Based on these results, this paper suggested securing social support and sustainability for the policy by reflecting users' demand in landscape planning related to the increase of UGS in the city. This study can contribute to improving the resilience of UGS and the sustainability of urban space planning.

Structural characteristics of dissolved black carbon and its interactions with organic and inorganic contaminants: A critical review.

Biochar (BC) is a sustainable and renewable carbonaceous material, and its soluble component, dissolved black carbon (DBC), is the key to understanding BC's geological and environmental processes. Although the relationship between the changes in DBC structure and its properties, functions, and associated environmental risks has been explored, a gap remains in our understanding of DBC's fate and behavior in the natural environment. Thus, in this review, we have highlighted the molecular and chemical compositions and the structural evolution of DBC during pyrolysis, the influence of DBC's physicochemical properties on its fate and transport, DBC's interaction with soil and its contaminants, and DBC stability in soil and water environments along with potential risks. Based on our in-depth assessment of DBC and its biogeochemical roles, we believe that future studies should focus on the following: (1) using advanced techniques to understand the chemical and molecular structure of DBC deeply and concisely and, thus, determine its fundamental role in the natural environment; (2) investigating the multi-functional properties of DBC and its interaction mechanisms; and (3) evaluating the environmental behaviors of and risks associated with DBC after BC application. In future, it is necessary to gain a deeper insight into the fate and transport of DBC with contaminants and study its associated risks under BC application in the environment.

Application of integrated Korean forest growth dynamics model to meet NDC target by considering forest management scenarios and budget.

BACKGROUND: Forests are atmospheric carbon sinks, whose natural growth can contribute to climate change mitigation. However, they are also affected by climate change and various other phenomena, for example, the low growth of coniferous forests currently reported globally, including in the Republic of Korea. In response to the implementation of the Paris Agreement, the Korean government has proposed 2030 greenhouse gas roadmap to achieve a Nationally Determined Contribution (NDC), and the forest sector set a sequestration target of 26 million tons by 2030. In this study, the Korean forest growth model (KO-G-Dynamic model) was used to analyze various climate change and forest management scenarios and their capacity to address the NDC targets. A 2050 climate change adaptation strategy is suggested based on forest growth and CO2 sequestration. RESULTS: Forest growth was predicted to gradually decline, and CO2 sequestration was predicted to reach 23 million tons per year in 2050 if current climate and conditions are maintained. According to the model, sequestrations of 33 million tCO2 year-1 in 2030 and 27 million tCO2 year-1 in 2050 can be achieved if ideal forest management is implemented. It was also estimated that the current forest management budget of 317 billion KRW (264 million USD) should be twice as large at 722 billion KRW (602 million USD) in the 2030s and 618 billion KRW (516 million USD) in the 2050s to achieve NDC targets. CONCLUSIONS: The growth trend in Korea's forests transitions from young-matured stands to over-mature forests. The presented model-based forest management plans are an appropriate response and can increase the capacity of Korea to achieve its NDC targets. Such a modeling can help the forestry sector develop plans and policies for climate change adaptation.

The initial effects of microclimate and invertebrate exclusion on multi-site variation in the mass loss of temperate pine and oak deadwoods.

Quantifying deadwood decomposition is prioritized by forest ecologists; nonetheless, uncertainties remain for its regional variation. This study tracked variations in deadwood decomposition of Korean red pine and sawtooth oak in three environmentally different regions of the Republic of Korea, namely western, eastern, and southern regions. After 24 months, dead pine and oak woods lost 47.3 ± 2.8% and 23.5 ± 1.6% in the southern region, 13.3 ± 2.6% and 20.2 ± 2.8% in the western region, and 11.9 ± 7.9% and 13.9 ± 2.3% in the eastern region, respectively. The regional variation in the decomposition rate was significant only for dead pine woods (P < 0.05). Invertebrate exclusion treatment reduced the decomposition rate in all region, and had the greatest effect in the southern region where warmer climate and concentrated termite colonization occurred. The strongest influential factor for the decomposition of dead pine woods was invertebrate exclusion (path coefficient: 0.63). Contrastingly, the decomposition of dead oak woods was highly controlled by air temperature (path coefficient: 0.88), without significant effect of invertebrate exclusion. These findings reflect the divergence in regional variation of deadwood decomposition between pine and oak, which might result from the different sensitivity to microclimate and decomposer invertebrates.

Microbial biomass and enzymatic responses to temperate oak and larch forest thinning: Influential factors for the site-specific changes.

Microbial biomass and enzyme activity are essential for ecosystem function in managed forests; however, uncertainty remains because microbial biomass and enzymatic responses to thinning highly differ with case studies. This study addressed the drivers for the site-specific responses of microbial biomass and enzyme activity to thinning. Study sites included two oak and three larch forests; each had un-thinned control, intermediate thinning (15-23% basal area reduction), and heavy thinning treatments (30-44% basal area reduction). Soil properties (temperature, water content, pH, total and inorganic nitrogen, and total carbon/nitrogen ratio), microbial biomass, enzyme (ß-glucosidase, N-acetylglucosaminidase, leucyl aminopeptidase, acid phosphatase, and phenol oxidase) activity, and soil carbon storage were determined 6 years after thinning. Compared to the control, microbial biomass carbon and nitrogen were higher under the intermediate and the heavy thinning by 13.9 and 24.4% and 11.5 and 29.9% at one oak forests, respectively, and higher under the intermediate thinning by 53.7 and 70.7% at one larch forests. There were the post-thinning changes in leucyl aminopeptidase activity by -46.9% and by 150.0-210.0% at an oak and larch forest, respectively, acid phosphatase activity by 60.0% at one oak forest, and phenol oxidase activity by 355.0% at one oak forest. The effect sizes of thinning for soil properties explained 94% and 77% of variance of the effect sizes for microbial biomass and enzyme activity. Especially, the effect sizes for soil water content, NH4+, total carbon/nitrogen ratio, and temperature were the most influential. Furthermore, the effect size for soil carbon storage was parabolically related to the effect size for microbial biomass carbon (R2 = 0.66). These findings highlight that inconsistent thinning effects on soil properties varied microbial biomass and enzymatic responses to thinning, which differentiated the change in soil carbon storage across sites. Future studies should consider such inconsistencies when examining the effects of forest management.

Estimating the effect of abandoning coppice management on carbon sequestration by oak forests in Turkey with a modeling approach.

A significant area of the oak forests in Turkey has been historically managed by short-rotation coppicing for wood production. Coppice management was almost abandoned in Turkey in 2006 and so investigating its impact on forest carbon (C) sequestration has become an important issue. Therefore, we investigated the net effect of this change in management on C sequestration by oak forests in Turkey using field measurement data and a forest C model (Forest Biomass and Dead organic matter Carbon (FBDC) model). The FBDC model estimated the annual forest C dynamics and considered the effect of the substitution of wood for fossil fuels under two management scenarios over a 100-year period: (1) abandoning coppice (no management) and (2) continuing coppice (20-year-interval harvest). The field measurement data were used to parameterize the FBDC model to the study sites and to verify the simulated C stocks. Continuing coppice management constrained an increase in the C stocks (116.0-140.3 Mg C ha-1) and showed a mean annual C sequestration of 0.6 Mg C ha-1 yr-1 if wood was substituted for fossil fuels. In contrast, abandoning coppicing practices increased the level of forest C stocks (128.1-236.2 Mg C ha-1), enhancing the mean annual C sequestration to 1.1 Mg C ha-1 yr-1. Accordingly, the abandonment of coppice management increased the mean annual C sequestration by 0.5 Mg C ha-1 yr-1 in the long-term. However, sensitivity analysis showed a possibility of a larger difference in C sequestration between the two scenarios due to a decrease in the stand productivity by repeated coppices and a high likelihood of a lower substitution effect. The verification supported the scientific reliability of the simulation results. Our study can provide a scientific basis for enhancing C sequestration in coppice forests.

Forest biomass carbon sinks in East Asia, with special reference to the relative contributions of forest expansion and forest growth.

Forests play an important role in regional and global carbon (C) cycles. With extensive afforestation and reforestation efforts over the last several decades, forests in East Asia have largely expanded, but the dynamics of their C stocks have not been fully assessed. We estimated biomass C stocks of the forests in all five East Asian countries (China, Japan, North Korea, South Korea, and Mongolia) between the 1970s and the 2000s, using the biomass expansion factor method and forest inventory data. Forest area and biomass C density in the whole region increased from 179.78 × 10(6) ha and 38.6 Mg C ha(-1) in the 1970s to 196.65 × 10(6) ha and 45.5 Mg C ha(-1) in the 2000s, respectively. The C stock increased from 6.9 Pg C to 8.9 Pg C, with an averaged sequestration rate of 66.9 Tg C yr(-1). Among the five countries, China and Japan were two major contributors to the total region's forest C sink, with respective contributions of 71.1% and 32.9%. In China, the areal expansion of forest land was a larger contributor to C sinks than increased biomass density for all forests (60.0% vs. 40.0%) and for planted forests (58.1% vs. 41.9%), while the latter contributed more than the former for natural forests (87.0% vs. 13.0%). In Japan, increased biomass density dominated the C sink for all (101.5%), planted (91.1%), and natural (123.8%) forests. Forests in South Korea also acted as a C sink, contributing 9.4% of the total region's sink because of increased forest growth (98.6%). Compared to these countries, the reduction in forest land in both North Korea and Mongolia caused a C loss at an average rate of 9.0 Tg C yr(-1), equal to 13.4% of the total region's C sink. Over the last four decades, the biomass C sequestration by East Asia's forests offset 5.8% of its contemporary fossil-fuel CO2 emissions.

Single-walled carbon nanotubes alter soil microbial community composition.

Recent developments in nanotechnology may lead to the release of nanomaterials into the natural environment, such as soils, with largely unknown consequences. We investigated the effects of single-walled carbon nanotubes (SWCNTs), one of the most widely used nanomaterials, on soil microbial communities by incubation of soils to which powder or suspended forms of SWCNTs were added (0.03 to 1 mg g(-1) soil). To determine changes in soil microbial community composition, phospholipid fatty acid (PLFA) profiles were analyzed at 25th day of the incubation experiment. The biomass of major microbial groups including Gram-positive and Gram-negative bacteria, and fungi showed a significant negative relationship with SWCNT concentration, while the relative abundance of bacteria showed a positive relationship with SWCNT concentration. Furthermore, soils under distinct concentrations of SWCNT treatments had PLFA profiles that were significantly different from one another. Our results indicate that the biomass of a broad range of soil microbial groups is negatively related with SWCNT concentration and upon entry into soils, SWCNTs may alter microbial community composition. Our results may serve as foundation for scientific guideline on regulating the discharge of nanomaterials such as SWCNTs to the soil ecosystem.

Experimental warming studies on tree species and forest ecosystems: a literature review.

Temperature affects a cascade of ecological processes and functions of forests. With future higher global temperatures being inevitable it is critical to understand and predict how forest ecosystems and tree species will respond. This paper reviews experimental warming studies in boreal and temperate forests or tree species beyond the direct effects of higher temperature on plant ecophysiology by scaling up to forest level responses and considering the indirect effects of higher temperature. In direct response to higher temperature (1) leaves emerged earlier and senesced later, resulting in a longer growing season (2) the abundance of herbivorous insects increased and their performance was enhanced and (3) soil nitrogen mineralization and leaf litter decomposition were accelerated. Besides these generalizations across species, plant ecophysiological traits were highly species-specific. Moreover, we showed that the effect of temperature on photosynthesis is strongly dependent on the position of the leaf or plant within the forest (canopy or understory) and the time of the year. Indirect effects of higher temperature included among others higher carbon storage in trees due to increased soil nitrogen availability and changes in insect performance due to alterations in plant ecophysiological traits. Unfortunately only a few studies extrapolated results to forest ecosystem level and considered the indirect effects of higher temperature. Thus more intensive, long-term studies are needed to further confirm the emerging trends shown in this review. Experimental warming studies provide us with a useful tool to examine the cascade of ecological processes in forest ecosystems that will change with future higher temperature.

High concentrations of single-walled carbon nanotubes lower soil enzyme activity and microbial biomass.

Nanomaterials such as single-walled carbon nanotubes (SWCNTs) may enter the soil environment with unknown consequences resulting from the development of nanotechnology for a variety of applications. We determined the effects of SWCNTs on soil enzyme activity and microbial biomass through a 3-week incubation of urban soils treated with different concentrations of SWCNTs ranging from 0 to 1000 µg g(-1) soil. The activities of cellobiohydrolase, ß-1,4-glucosidase, ß-1,4-xylosidase, ß-1,4-N-acetylglucosaminidase, L-leucine aminopeptidase, and acid phosphatase and microbial biomass were measured in soils treated with powder and suspended forms of SWCNTs. SWCNTs of concentrations at 300-1000 µg g(-1) soil significantly lowered activities of most enzymes and microbial biomass. It is noteworthy that the SWCNTs showed similar effects to that of multi-walled carbon nanotubes (MWCNTs), but at a concentration approximately 5 times lower; we suggest that this is mainly due to the higher surface area of SWCNTs than that of MWCNTs. Indeed, our results show that surface area of CNTs has significant negative relationship with relative enzyme activity and biomass, which suggests that greater microorganism-CNT interactions could increase the negative effect of CNTs on microorganisms. Current work may contribute to the preparation of a regulatory guideline for the release of CNTs to the soil environment.

The effect of multi-walled carbon nanotubes on soil microbial activity.

Nanomaterials such as multi-walled carbon nanotubes (MWCNTs) are applied to various industrial products and thus may be released to soils, but their potential environmental impacts remain largely undetermined. We investigated the short-term effect of MWCNTs on the activity and biomass of microorganisms inhabiting two different soil types in an incubation study. Up to 5000 µg MWCNT g(-1) soil was applied and the activities of 1,4-ß-glucosidase, cellobiohydrolase, xylosidase, 1,4-ß-N-acetylglucosaminidase, and phosphatase and microbial biomass were measured. In both soil types, most enzyme activities showed a tendency to be repressed under 500 µg MWCNT g(-1) soil, and all enzymatic activities as well as microbial biomass C and N were significantly lowered under 5000 µg MWCNT g(-1) soil. Our results suggest that high concentrations of MWCNTs could lower the microbial activity and biomass in soils, and they may serve as an important guideline in regulating the release of MWCNTs to the soil environment.

Changes in the distribution of South Korean forest vegetation simulated using thermal gradient indices.

To predict changes in South Korean vegetation distribution, the Warmth Index (WI) and the Minimum Temperature of the Coldest Month Index (MTCI) were used. Historical climate data of the past 30 years, from 1971 to 2000, was obtained from the Korea Meteorological Administration. The Fifth-Generation National Center for Atmospheric Research (NCAR) /Penn State Mesoscale Model (MM5) was used as a source for future climatic data under the A1B scenario from the Special Report on Emission Scenario (SRES) of the Intergovernmental Panel on Climate Change (IPCC). To simulate future vegetation distribution due to climate change, the optimal habitat ranges of Korean tree species were delimited by the thermal gradient indices, such as WI and MTCI. To categorize the Thermal Analogy Groups (TAGs) for the tree species, the WI and MTCI were orthogonally plotted on a two-dimensional grid map. The TAGs were then designated by the analogue composition of tree species belonging to the optimal WI and MTCI ranges. As a result of the clustering process, 22 TAGs were generated to explain the forest vegetation distribution in Korea. The primary change in distribution for these TAGs will likely be in the shrinkage of areas for the TAGs related to Pinus densiflora and P. koraiensis, and in the expansion of the other TAG areas, mainly occupied by evergreen broad-leaved trees, such as Camellia japonica, Cyclobalanopsis glauca, and Schima superba. Using the TAGs to explain the effects of climate change on vegetation distribution on a more regional scale resulted in greater detail than previously used global or continental scale vegetation models.

Carbon and nitrogen storage in an age-sequence of Pinus densiflora stands in Korea.

The carbon (C) and nitrogen (N) storage capabilities of Pinus densiflora in six different stand ages (10, 27, 30, 32, 44, and 71 years old) were investigated in Korea. Thirty sample trees were destructively harvested and 12 were excavated. Samples from the above and belowground tree components, coarse woody debris (CWD), forest floor, and mineral soil (0-30 cm) were collected. Tree biomass was highest in the 71-year-old stand (202.8 t ha(-1)) and lowest in the 10-year-old stand (18.4 t ha(-1)). C and N storage in the mineral soil was higher in the 71-year-old stand than in the other stands, mainly due to higher soil C and N concentrations. Consequently, the total ecosystem C and N storage (tree+forest floor+CWD+soil) was positively correlated with stand age: increasing from a minimum in the 10 year old stand (18.8 t C ha(-1) and 1.3 t N ha(-1)) to a maximum in the 71-year-old stand (201.4 t C ha(-1) and 8.5 t N ha(-1)). The total ecosystem C storage showed a similar sigmoidal pattern to that of tree C storage as a function of the age-sequence, while N storage in the CWD, forest floor and mineral soil showed no significant temporal trends. Our results provide important insights that will increase our understanding of C and N storage in P. densiflora stands and our ability to predict changes according to stand age in the region.