• Journal of Forest and Environmental Science
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• 제31권1호
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• pp.14-23
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• 2015

In this study, we investigated the effects of three land uses on soil properties in two soil layers; surface soil (0~15 cm) and subsoil (15~30 cm). Soil samples were collected from planted forest, barren lands and cultivated lands from different areas in Chittagong Cox's Bazar and analyzed for some physical and chemical properties. Results showed that soil textural class varied from sandy clay loam in planted forest and barren land site to sandy loam in cultivated soils. Maximum water holding capacity was higher in forest followed by barren land and the lowest in cultivated lands. At both soil depths, soils of cultivated land showed the highest values of bulk density (1.42 to $1.50g\;cm^{-3}$), followed by barren lands (1.37 to $1.46g\;cm^{-3}$) and the least (1.32 to $1.45g\;cm^{-3}$) in forest soils. Total porosity decreased with depth ranging from 40.24% to 41.53% in subsoils and from 42.04 to 43.23% in surface soil of cultivated and of planted forest sites respectively. The result further revealed that organic carbon (OC) and total nitrogen (TN) contents were higher in the planted forest soil than in other two land uses. The soils of all land uses under study are acidic in nature and the lowest pH was found in both surface and subsoils of barren land. Cultivated soil contained the highest amount of available P, Ca, Mg and K in both surface soil and subsoils. In contrast, barren site had the lowest contents of available P, Ca, Mg and K in both layers. The soil organic carbon (SOC) and total N storage were higher in planted forest than in barren and cultivated land uses.

• Current Research on Agriculture and Life Sciences
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• 제23권
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• pp.53-60
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• 2005

본 연구는 경주남산의 산림토양의 이화학적 특성을 분석하여 산림의 다목적이용과 남산의 산림보호 관리에 도움을 주고자 실시하였다. 조사지는 각 층위별로 토양성분을 분석하였고, 그 결과는 다음과 같다. 남산 산림토양의 물리적 특성은 토심이 31.4cm 이고 유효토심은 20.0cm 였으며 유기물층의 깊이는 5.9cm였다. 계곡부를 제외한 다른 조사지의 토성은 사질 양토이었다. 전체 토양 pH는 평균 4.76으로 우리나라 산림토양의 평균보다 낮게 나타났으며 유효인산의 함량은 평균 3.64로 유효인산의 함량이 매우 적은 것으로 나타났다. 치환성양이온($Ca^{2+}$, $Mg^{2+}$, $K^+$, $Na^+$)의 함량은 우리나라 산림토양의 함량과 보다 낮은 수치를 나타내었으며 특히 $Ca^{2+}$함량은 우리나라 산림토양의 평균 $2.44cmol_c/kg$보다 낮은 함량인 $1.04cmol_c/kg$를 나타내었다.

• Journal of Forest and Environmental Science
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• 제39권1호
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• pp.13-19
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• 2023

We investigated Soil respiration in Bluepine forest of western Bhutan, in relation to soil temperature, moisture content and soil pH and it was aimed at establishing variability in space and time. The Bluepine forest thrives in the typical shallow dry valleys in the inter-montane Bhutan Himalaya, which is formed by ascending wind from the valley bottom, which carries moisture from the river away to the mountain ridges. Stratified random sampling was applied and the study site was classified into top, mid, low slope and further randomized sample of n=20 from 30 m×30 m from each altitude. The overall soil respiration mean for the forest was found 2248.17 CO₂ g yr^-1 and it is ~613.58 C g yr^-1. The RS from three sites showed a marginal variation amongst sites, lower slope (2,309 m) was 4.64 μ mol m^-2 s^-1, mid slope (2,631 m) was 6.78 μ mol m^-2 s^-1 and top slope (3,027 m) was 6.33 μ mol m^-2 s^-1 and mean of 5.92 μ mol m^-2 s^-1, SE=0.25 for the forest. Temporal distribution and variations were observed more pronounced than in the space variation. Soil respiration was found highest during March and lowest in September. Soil temperature had almost inverse trend against soil respiration and dropped a low in February and peak in July. The moisture in the soil changed across months with precipitation and pH remained almost consistent across the period. The soil respiration and soil temperature had significant relationship R²=-0.61, p=0.027 and other variables were found insignificant. Similar relationship are reported for dry season in a tropical forest soil respiration. Soil temperature was found to have most pronounced effect on the soil respiration of the forest under study.

• 한국환경복원기술학회지
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• 제11권3호
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• pp.20-27
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• 2008

This study was conducted to investigate the influence of thinning and pruning on characteristics of forest stand, mesopore ratio and soil water content at the Pinus koraiensis stands in Gwangneung, Gyeonggido. The Pinus koraiensis had been planted in 1976 and thinning and pruning were carried out in 1996. A sample area survey was conducted at experimental plots (thinned and unthinned) in 1998 and 2005, and mesopore ratio and soil water content have been monitored from 2000 to present. Average tree height of the thinned plot increased from 10.9m to 13.2m and from 10.3m to 12.8m for the unthinned plot. Average D.B.H of the thinned plot increased from 15.9cm to 21.1cm and from 14.5cm to 16.7cm for the unthinned plot during the period 1998-2005. Crown density at the thinned plot increased from 81.5% to 95.0% and from 89.5% to 95.0% for the unthinned plot during the period 1998-2005. Mesopore ratio (pF2.7) of A layer soil at the thinned plot was 40.1% while that of the unthinned plot was 37.3%. Changes of mesopore ratio at unthinned plot were not associated with stand age, but those at thinned plot had increased and then decreased, showing declining of the practice effect. Average soil water content at the thinned plot were 23.7% and 22.4% for the unthinned plot. Soil watercontents at both plots have been increased with increase in stand age. But the difference of soil watercontent at each plot has been decreased, especially at the depth of 10cm.

• 한국산림과학회지
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• 제90권3호
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• pp.242-248
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• 2001

토지 이용 변화는 토양 내 유기물과 양분 상태에 영향을 줄 것으로 기대된다. 본 연구에서는 경기도 광주군 검단산 일대에서 과거 논으로 이용되다가 현재는 버드나무-신나무 우점의 산림으로 변한 지역, 밭에서 잣나무 인공조림지로 변한 지역, 그리고 과거부터 지속적으로 참나무류가 우점하고 있는 산림 지역 등 세 가지 토지 이용 형태를 선정하고 여기에서 토양 내 탄소와 질소의 농도, 토양 호흡, 그리고 질소 유효도 등을 측정, 비교하였다. 경작지의 휴경 후 20년이 경과한 다음, 토양 내 탄소와 질소의 농도는 토양 깊이 0-10cm, 10-20cm에서 과거 논이었던 지역이 다른 지역에 비하여 높은 것으로 나타났다. 또한 일반적으로 탄소와 질소의 농도는 표층에서 높고 토양 깊이가 증가할수록 점차 낮아지는 경향을 보였다. 이것은 유기물의 유입과 분해의 차이로 인한 축적량이 과거 논이었던 지역에서 가장 많기 때문이며, 탄소와 질소의 증가는 주로 표층에 국한한데에 기인하는 것으로 보인다. 토양 발생 이산화탄소량은 논에서 산림으로 변한 지역에서 가장 높게 나타났으며, 이는 토양 내 높은 탄소 농도와 습윤한 수분 조건 때문인 것으로 보인다. 이온교환수지봉지법으로 측정한 토양 내 질소 유효도는 토지 이용 형태에 따라 유의한 차이를 나타내었는데, 무기태 질소 $NH_4{^+}+NO_3{^-}$)의 유효도와 암모니움태 질소의 농도는 산림지역에서 가장 높고, 밭에서 산림으로 변한 지역, 논에서 산림으로 변한 지역의 순으로 점차 감소하였다.

• 한국자원식물학회지
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• 제34권6호
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• pp.566-574
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• 2021

This research was carried out to investigate the correlation between soil chemical properties and bioactive compounds of Acer tegmentosum Maxim. The methods of determining bioactive compounds were determined by high performance liquid chromatography, that contained (-)-gallocatechin (0.04±0.01 ~ 0.43±0.28%), salidroside (0.90±0.06 ~ 3.86±0.59%), tyrosol (0.03±0.00 ~ 0.43±0.00%), (-)-catechin (0.05±0.01 ~ 0.37±0.14%), 6'-O-galloylsalidroside (0.02± 0.01 ~ 0.31±0.06%), (-)-epicatechin-gallate (0.01±0.00 ~ 0.04±0.01%). The soil chemical properties analysis such as soil pH, electric conductivity (EC), organic matter (OM), total nitrogen (TN), available phosphate (Avail. P₂O₅), exchangeable cation and cation exchange capacity (CEC) were performed following the standard manual. The correlation analysis between soil chemical properties and bioactive compounds of A. tegmentosum, soil pH, available phosphate and exchangeable cation (Ca²⁺ and Mg²⁺) were negatively correlated with content of salidroside. On the other hand, soil exchangeable cation (Na⁺) showed positive correlation with content of salidroside. The results of this study was able to investigate the correlation between soil chemical properties and bioactive compounds of A. tegmentosum.

• Journal of Forest and Environmental Science
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• 제36권2호
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• pp.133-142
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• 2020

Soil physical and chemical properties at three layers such as top (0-10 cm), middle (10-20 cm) and bottom (20-30 cm) layers under three different vegetation types were studied. Soil samples were collected from Acacia forest, vegetable and fallow lands of Chittagong university campus, Chittagong, Bangladesh. Results showed that sand was the dominant soil particle followed by clay and silt fractions in all soil depths under different vegetation types. Soils of fallow land showed the highest values of bulk density while forest soils had the lowest values at three depths. Acacia forest soil having lowest values of dispersion ratio (DR) is less vulnerable while fallow soil with highest DR values is more vulnerable to soil erosion. The lower pH value at all soil layers in three ecosystems represented that soils under study are acidic in nature. Contents of organic matter, total nitrogen, exchangeable cations (Ca²⁺, Mg²⁺, K⁺ and Na⁺) and cation exchange capacity (CEC) were observed higher in Acacia forest soils compared to vegetable and fallow soils. Only soils of vegetable land had higher level of available phosphorus in three layers than that of other two land covers. The study also revealed that different soil properties were observed in three different vegetation types might be due to variation in vegetation and agronomic practices.

• 한국환경복원기술학회지
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• 제9권3호
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• pp.76-81
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• 2006

The reinforcement of soil shear strength by nylon net as substitute materials simulating a fine root system was evaluated by soil strength parameters(apparent cohesion(c) and internal friction angle(tan${\phi}$), using simple shear tester which clearly depicts shear deformation and controls soil suction. And the results of shear test by using bamboo as a substitute materials simulating a main root system and using nylon net as a substitute materials simulating a fine root system were compared. The reinforcement of soil strength by nylon net are expressed by apparent cohesion more than internal friction angle. In addition the increment of apparent cohesion by nylon net reached a peak in suction 60 $cmH_2O$. Different from with bamboo, the possibility of the change on internal friction angle(tan${\phi}$) caused by the soil water condition was shown in shear strain 20% condition. These results show that the mechanism of reinforcement by substitute materials simulating root system may be different in the condition of various soil water content.

• 한국환경복원기술학회지
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• 제15권6호
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• pp.61-67
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• 2012

This study was conducted to evaluate the effects of soil covering and vegetation base materials implementation on the growth of Lespedeza cyrtobotrya Miq. in abandoned coal mine land. We compared the biomass of L. cyrtobotrya at the study plots of four different soil covering depth (control, 10cm, 20cm, and 30cm) and four different compounds of vegetation base materials composed of soil conditioner (S), erosion control (E), and peat moss (P) (control, S+P, E+P, and S+E+P). The result showed that the biomass of L. cyrtobotrya was higher in the study plots implemented with soil covering than control plot, although the increase in biomass was not constant with soil covering depth. In case of the vegetation base materials treatments, the biomass was highest in S+E+P plot, and S+P and E+P plots showed higher biomass than control plot.

• 한국산림과학회지
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• 제110권4호
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• pp.479-495
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• 2021

산림자원의 효율적인 관리를 위해서는 산림입지환경에 대한 종합 데이터베이스의 기반이 되는 산림입지토양도가 필요하다. 국내에서 그동안 1:25,000 산림입지도가 제작되어 사용되어왔으나 높은 정밀도와 개별 목적에 특화된 산림입지정보를 갖춘 대축척 산림입지토양도의 필요성이 대두되었다. 이에 따라 2009년부터 2021년까지 1:5,000 축척의 산림입지토양도 제작사업이 진행되었다. 이와 관련하여 본 논문에서 1:5,000 산림입지토양도 제작 과정과 주요 결과, 활용 방안과 향후 발전 방향을 알아보고자 하였다. 산림입지토양도 제작은 표준매뉴얼에 따라 진행되었으며, 조사 및 분석 결과를 바탕으로 토양형, 토심, 토성별 전국 단위 지도가 작성되었다. 산림입지토양도 자료는 다양한 주제도 제작의 기초가 되며, 산림재해의 방지 및 예측과 환경용량 평가 등에 활용될 수 있다. 그러나 앞으로 산림경영 선진화와 디지털 사회로의 전환에 맞추어 산림입지토양도의 제작 방법을 발전시키고 그 활용방안도 다각화시킬 필요도 있다. 이를 바탕으로 국가 산림기본계획 목표 달성을 위한 다양한 정보 제공, 산림 빅데이터 확보 및 국가 발전 계획에 상응하는 지속가능한 산림경영의 실현 등을 기대할 수 있을 것이다.