• The Korean Journal of Ecology
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• v.28 no.4
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• pp.181-188
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• 2005

Methods used to study carbon sequestration by soil aggregates have often excluded the concentric spatial variability and other dynamic processes that contribute to resource accessibility and solute transport within aggregates. We investigated the spatial gradients of carbon (C) and nitrogen (N) from the exterior to interior layers within macroaggregates, $6.3\sim9.5$ mm, sampled from conventional tillage (CT) and no tillage (NT) sites of a Hoytville silt clay loam. Spatial gradients in C accumulation within macroaggregates were related to the differences in C dynamics by determining the sizes and the turnover rates of fast C and slow C pools in the concentric layers of aggregates. Aggregate exteriors contained more labile C and were characterized by greater C mineralization rates than their interiors in both management systems. In contrast, C in the interior layers of aggregates was more resistant in both systems. These results indicated the spatial differentiation of C dynamics within macroaggregates, i.e., exterior layers as a reactive site and interior layers as a protective site. Greater total C distribution in the exterior layers of NT aggregates indicated more influx of C from the macropores in interaggregate space than C. mineralization (net gain of C), whereas lower C distribution within the exterior layers of CT aggregates indicated net loss of C by greater C mineralization than C influx. We found total C increased approximately 1.6-fold by the conversion of CT soils to NT management systems for a period of 36 years. Differences in total accumulation and the spatial distribution of C within aggregates affected by management were attributed to the differences in aggregate stability and pore networks controlling the spatial heterogeneities of resource availability and microbial activity within aggregates.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.5
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• pp.33-46
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• 2023

In this study, carbon storage in the aboveground biomass, litter layer, and soil layer was calculated for abandoned mining restoration areas to determine the level of carbon storage after the restoration project through comparison with the ecological reference. Five survey sites were selected for each abandoned mining restoration area in Boryeong-si, Chungcheongnam-do, and the ecological reference that can be a goal and model for the restoration project. The carbon storage in the restoration area was 0~21.3Mg C ha^-1, the deciduous layer 3.3~6.0Mg C ha^-1, and the soil layer(0-30cm) 8.3~35.1Mg C ha^-1, showing a significant difference in carbon storage by target site. The total carbon storage was between 6.1 and 35.3% of the ecological reference, with restoration area ranging from 14.0 to 62.4 Mg C ha^-1. The total carbon storage in the restoration area and the ecological reference differed the most in the aboveground biomass and was less than 12%. Based on these results, forest restoration area need to improve the carbon storage of forests through continuous management and monitoring so trees can grow and restore productivity in the early stages of the restoration project. The results of this study can be used as primary data for preparing future forest restoration indicators by identifying the storage of abandoned mining restoration areas.

• Korean Journal of Environmental Biology
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• v.26 no.3
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• pp.170-176
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• 2008

Organic carbon distribution and carbon budget of a Quercus variabilis forest in the Youngha valley of Mt. Worak National Park were investigated. Carbon in above and below ground standing biomass, litter layer, and soil organic carbon were measured from 2005 through 2006. For the estimation of carbon budget, soil respiration was measured. The amount of carbon allocated to above- and below-ground biomass was 56.22 and 13.90 ton C ha$^{-1}$. Amount of organic carbon in annual litterfall was 2.33 ton C ha$^{-1}$ yr$^{-1}$. Amount of soil organic carbon within 50 cm soil depth was 119.14 ton C ha$^{-1}$ 50 cm-depth$^{-1}$. Total amount of organic carbon in this Q. variabilis forest was 193.96 ton C ha$^{-1}$. Of these, 61.43% of organic carbon was allocated in the soil. Net increase of organic carbon in above- and below-ground biomass in this Q. variabilis forest was estimated to 7.68 ton C ha$^{-1}$ yr$^{-1}$. The amount of carbon evolved through soil respiration was 6.21 ton C ha$^{-1}$ yr$^{-1}$. Net amount of 1.47 ton C ha$^{-1}$ yr$^{-1}$ was absorbed from the atmosphere by this Q. variabilis forest.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.260-265
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• 2012

Soil respiration under flooded conditions is considered to be very small compared with aerobic soil respiration of soil organic matter. However, anaerobic decomposition of soil plays a key role in carbon cycling in flooded ecosystems. On the other hand, coal-ash wastes, such as fly ash and bottom ash, are known to function as a soil amendment for mitigating $CO_2$ emission and enhancing carbon sequestration in up land soils. In this study, we investigated bottom ash as a soil amendment for mitigating $CO_2$ emission, and thus enhancing carbon sequestration under anaerobic conditions. We observed that amendment of bottom ash without external organic source led to significant reduction in $CO_2$ emission rate and in total cumulative $CO_2$ emission flux over the incubation period, which was proportional to the amount of bottom ash applied. We also found that soil microbial biomass increased in response to application of bottom ash. These results suggest that bottom ash can be utilized to store $CO_2$ as a stable soil organic carbon in flooded ecosystems, as in aerobic situations.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.602-608
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• 2007

Forest plantations become important strategy not merely for the financial aspect, but for carbon sequestration and ecosystem stability. Forest plantations increase the density of the forest biomass, which reduce the increase in atmospheric carbon dioxide. Biomass density is also a useful variable for comparing structural and functional attributes of forest ecosystems across a wide range of environmental conditions. In this study, carbon sequestration of teak (Tectona grandis Linn. f.) in the individual tree and plantation levels estimation was carried out Site-specific allometric equation for the estimation of teak tree biomass was developed based on the direct measurement of fifteen (15) harvested trees in the Oak-twin Township of the Bago Yoma Region, Myanmar. A regression equation of the diameter at breast height (DBH) and the aboveground biomass (carbon content) was constructed to estimate the carbon storage level of plantations, which averaged 79 ton/ha. The average carbon accumulation in the soil (up to 30 cm in depth) was estimated 38.89 ton/ha, The highest mean annual increment (MAI) of total carbon was found in the 6-yr-old teak plantation (12.10 ton/ha/yr) whereas the lowest MAI was in the 26-yr-old teak plantation (4.31 ton/ha/yr).

• Journal of Ecology and Environment
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• v.43 no.1
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• pp.43-60
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• 2019

Background: Tropical montane forests played an important role in the provision of ecosystem services. The intense degradation and deforestation for the need of agricultural land expansion result in a significant decline of forest cover. However, the expansion of agricultural land did not completely destruct natural forests. There remain forests inaccessible for agricultural and grazing purpose. Studies on these forests remained scant, motivating to investigate biomass and soil carbon stocks. Data of biomass and soils were collected in 80 quadrats ($400m^2$) systematically in 5 forests. Biomass and disturbance gradients were determined using allometric equation and disturbance index, respectively. The regression modeling is employed to explore the spatial distribution of carbon stock along disturbance and environmental gradients. Correlation analysis is also employed to identify the relation between site factors and carbon stocks. Results: The result revealed that a total of 1655 individuals with a diameter of ${\geq}5cm$, representing 38 species, were measured in 5 forests. The mean aboveground biomass carbon stocks (AGB CS) and soil organic carbon (SOC) stocks at 5 forests were $191.6{\pm}19.7$ and $149.32{\pm}6.8Mg\;C\;ha^{-1}$, respectively. The AGB CS exhibited significant (P < 0.05) positive correlation with SOC and total nitrogen (TN) stocks, reflecting that biomass seems to be a general predictor of SOCs. AGB CS between highly and least-disturbed forests was significantly different (P < 0.05). This disturbance level equates to a decrease in AGB CS of 36.8% in the highly disturbed compared with the least-disturbed forest. In all forests, dominant species sequestrated more than 58% of carbon. The AGB CS in response to elevation and disturbance index and SOC stocks in response to soil pH attained unimodal pattern. The stand structures, such as canopy cover and basal area, had significant positive relation with AGB CS. Conclusions: Study results confirmed that carbon stocks of studied forests were comparable to carbon stocks of protected forests. The biotic, edaphic, topographic, and disturbance factors played a significant variation in carbon stocks of forests. Further study should be conducted to quantify carbon stocks of herbaceous, litter, and soil microbes to account the role of the whole forest ecosystem.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.129-160
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• 2019

Background: Characterizing and describing soils and land use and make a suggestion for sustainable utilization of land resources in the Ethiopian Rift valley flat plain areas of Lake Chamo Sub-Basin (CSB) are essential. Objectives: To (1) characterize soils of experimental area according to World Reference Base Legend and assess the nature and extent of salinity problems; (2) characterize land use systems and their role in soil properties; and (3) identify best land use practices used for both environmental management and improve agricultural productivity. Methods: Twelve randomly collected soil samples were prepared from the above land uses into 120 composites and analyzed. Results: Organic carbon (OC) and total nitrogen (TN) were varied along different land uses and depleted from the surface soils. The soil units include Chernozems (41.67%), Kastanozems (25%), Solonchaks (16.67%), and Cambisols (16.67%). The identified land uses are annual crops (AA), perennial crops (PA), and natural forest (NF). Generally, organic carbon, total nitrogen, percentage base saturation (PBS), exchangeable (potassium, calcium, and magnesium), available phosphorus (P₂O₅), manganese, copper, and iron contents were decreased in cultivated soils. Soil salinity problem was observed in annuals. Annuals have less nutrient content compared to perennials in irrigated agriculture while it is greater in annuals under rainfed. Clay, total nitrogen, available phosphorus, and available potassium (K₂O) contents were correlated positively and highly significantly with organic carbon and electrical conductivity. Conclusion: Management practices that improve soil quality should be integrated with leguminous crops when the land is used for annual crops production.

• Journal of Life Science
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• v.20 no.10
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• pp.1468-1475
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• 2010

Sulfate reduction rates (SRR) using $^{35}SO_4^{-2}$, sulfide producing rates (SPR) using gas chromatography, the number of sulfate reducing bacteria (SRB) using the most probable number (MPN) method, and soil components (moisture, ammonium, total nitrogen, total organic carbon, total carbon, total inorganic phosphorus, total phosphorus, and sulfate) using standard methods in the organic/conventional rice paddy soils, cleaned/polluted reservoir soils, and cleaned/polluted foreshore soils were studied with the change of seasons. The average SRR was more related to the number of SRB and soil components (especially nitrogen and phosphorus) than sulfate concentration. SRR was also recorded to be highest in October soil samples. However, SPR was higher in foreshore soils containing a high concentration sulfate than in fresh water soils, and it was also recorded to be higher in the polluted areas than in clean areas. From these results, we can conclude that the SRR and SPR of anaerobic environments were affected by the number of SRB, soil components and temperature.

• Journal of Forest and Environmental Science
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• v.29 no.1
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• pp.29-37
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• 2013

The study was carried out in two different forest types viz., Banj oak and Chir pine forests to assess the variation in forest species composition and soil properties along altitudinal gradients in the Garhwal Himalayas. The results of the study showed that between the forests soil moisture was higher in Banj oak forest because of closed canopy and dense forest compared to Chir pine forest. The sand particles were reported higher in Banj oak forest which might be due to the addition of organic matter favouring coarse structure of soil, helping in holding maximum water in soils. However in the Chir pine forest low amount of soil organic matter and presence of clayey soil, develops soil compactness which reduces the penetration of water resulting in high soil bulk density. The higher accumulation of litter and presence of moisture in Banj oak forest favours higher nutrient level of nitrogen, phosphorus and potassium compared to Chir pine forest. The soil organic carbon also reduced with increasing altitude at both gradients. While bulk density has reverse trend with soil organic carbon in both the forests at different peaks of same region. In Banj oak forest, the highest density and total basal cover was reported 1,100 tree $ha^{-1}$ and 58.86 $m^2\;ha^{-1}$ respectively. However, the highest values of density and total basal cover of Chir pine forest was 560 tree$ha^{-1}$ and 56.94 $m^2\;ha^{-1}$ respectively. The total density and basal cover of both the forests reduced with increasing altitude. The study concludes that Banj oak forest has better nutrient cycling ability, well developed foest floor and has a greater protective and productive features compared to the Chir pine forest which is without lower vegetation cover and having only pine litter accumulation which does not allow any other species to grow.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.1
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• pp.193-206
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• 2013

This study was to provide the base data on the status of vegetations and soils in green roofs by analyzing the soil and vegetation characteristics of 4 green roofs in Dongguk University in September 2012. Sanglokwon(SW), Dongguk Hall(DH), University Library(UL), and Information and Culture Hall P(IC) were established in 2005, 2008, 2009, and 2010, respectively. The areas of green roofs were $700m^2$, $2,300m^2$, $1,240m^2$, and $640m^2$ in SW, DH, UL, and IC respectively. The investigated floras of vascular plants were 26 families, 55 genera, 65 species in Sanglokwon(SW), 53 families, 99 genera, 112 species in Dongguk Hall(DH), 43 families, 77 genera, 84 species in University Library(UL), and 41 families, 71 genera, 75 species in Information and Culture Hall P(IC), respectively. A positive correlation is shown between the number of plant species and planting area. Total nitrogen, organic matter, and potassium in soil have positive correlation with the number of plant species. The number of plant species was proportional to area and increased more than twice after planting. About a quarter of the invaded plants (including native and naturalized species) were naturalized plants. The total soil depths including vegetation soil and drainage soil at SW, DH, UL, and IC were 20cm, 10cm, 10cm, and 8cm, respectively. The depths of vegetation soil at SW, DH, UL, and IC were <7cm, <3cm, <2cm, and <2cm respectively. The soil pH in vegetation soil ranged from 5.22 to 5.36, and from 6.13 to 6.39 in drainage soil. Available-P concentration ranged from 10.17 to 189.77mg/kg in vegetation soil and from 6.70 to 81.17mg/kg in drainage soil. Carbon concentration in vegetation soil ranged from 2.93 to 9.70%, and 2.93 to 9.70% in drainage soil. Carbon contents in 20cm, 10cm, 10cm, and 8cm soil depths were $2.62kg/m^2$, $1.89kg/m^2$, $0.50kg/m^2$, and $0.53kg/m^2$ at SW, DH, UL, and IC, respectively.