• 한국지반환경공학회 논문집
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• 제2권1호
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• pp.103-114
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• 2001

본 연구에서는 근래에 퇴적된 습지토양의 유기물질에 느린 흡착부분이 존재하는지 살펴보기 위해 흡착실험을 행하였다. 최근 퇴적된 민물 습지토양에서의 소수성 유기화합물 (chlorobenzene and phenanthrene)의 흡착 특성을 회분식 흡착법을 사용하여 결정하였다. 유기물질의 나이의 상대 척도로서 산소/탄소 원소비 등을 포함한 여러 방법으로서 평가하였다. 토양의 나이가 유기화합물의 습지토양에서의 흡착에 차이를 유발하는지에 대해 조사하기 위하여 습지 토양의 표층부(상층부 0-2cm, 5년 미만)과 하층부(below 10cm, 20년 이상)에 대한 느린 흡착 특성을 상대적으로 오래된 PPI(Petro Processors, Inc. Superfund site), BM(Bayou Manchac) 토양과 비교하였다. 느린 흡착모델 변수의 비선형성(KF와 N)의 증가로서 느린 흡착부분이 존재함을 알 수 있었다. 느린 흡착모델의 분석결과 상당한 크기의 느린 흡착부분이 존재하였으며 습지 토양의 경우 흡착된 chlorobenzene의 25.4-263%가 phenanthrene의 경우 흡착된 양의 1.4-1.9%(phenanthrene)가 각각 느린 흡착 부분에 해당하였으며, PPI 토양과 BM토양의 경우 흡착된 chlorobenzene의 40.0-55.93%와 흡착된 phenanthrene의 2.9-3.19%가 각각 느린 흡착 부분에 해당하였다. 느린 흡착 부분은 상층부 < 하층부 < PPI < BM 토양의 순으로 증가하였는데 이것은 토양 유기물질의 나이가 증가할수록 느린 흡착부분의 크기가 증가함을 나타낸다.

• Ocean and Polar Research
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• 제27권1호
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• pp.1-13
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• 2005

The samples for organic carbon analysis were collected between $5^{\circ}\;and\;17^{\circ}N$ along $131.5^{\circ}W$ in the northeast Pacific KODOS (Korea Deep Ocean Study) area. The mean concentration of total organic carbon (TOC) in the surface mixed layer $({\sim}50 m)$ was $100.13{\pm}2.05{\mu}M-C$, while the mean concentration of TOC in the lower 500m of the water column was $50.19{\pm}4.23{\mu}M-C$. A strong linear regression between TOC and temperature $(r^2=0.70)$ showed that TOC distribution was controlled by physical process. Results from the linear regression between chlorophyll-a and TOC, and between chlorophyll-a and particulate organic carbon (POC), decreasing of dissolved organic carbon (DOC) in the surface layer caused by non-biological photo-oxidation process. Below the surface layer, biological production and consumption occurred. DOC accumulation dominated in the depth range of $30{\sim}50m$ and DOC consumption occurred in the depth range of $50{\sim}200m$. TOC was inversely correlated with apparent oxygen utilization (AOU) and TOC/AOU molar ratios ranged from -0.077 to -0.21. These ratios indicated that TOC oxidation was responsible fur $10.9{\sim}30.1%$ (mean 20.2%) of oxygen consumption in the NE Pacific KODOS area. In the euphotic zone, distributions of dissolved and particulate organic matter were controlled by photo-chemical, chemical, biological and physical processes.

• 한국토양비료학회지
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• 제29권4호
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• pp.419-423
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• 1996

대구 달서천 하수종말처리장에서 부생되어 나오는 도시하수오니의 유기질 비료자원으로서의 활용 가치를 보기 위하여 알타리무를 공시작물로 하여 시험한 결과는 다음과 같다. 1. 오니중 유기물, 질소, 인산 등의 함량이 각자 53.59, 2.87. 3.50%로 유기질 비료자원으로서 활용가치가 있는 것으로 기대되나, 카드뮴 및 납 함량이 각각 1.10, 28mg/kg이었다. 2. 오니의 시용으로 토양의 pH, 유기물 함량, 전질소 함량, 유효 인산 함량, 치환성 석회 및 고토 함량, 양이온치환용량 등이 증가되었으며, 중금속(Cd, Pb등) 함량도 다소 증가되는 경향이었다. 3. 오니의 시용으로 수확기 식물체중 질소 및 인산 함량이 증가되었으며, 중금속 원소인 카드뮴 및 납 함량도 증가되었으나, 그 정도는 카드뮴에서 현저하였다. 4. 오니의 시용은 알타리무의 수량을 증가시켰으나 표준시비량에 오니 2.000kg/10a 및 3.000kg/10a구와 오니 6.000kg/10a 단용구에서는 수량이 감소되어, 오니의 과다 시용은 작물 생육에 피해가 있는 것으로 판단되었다.

• 한국토양비료학회지
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• 제46권5호
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• pp.399-407
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• 2013

Organic grape was generally produced in rainshield or plastic greenhouse culture while most of fruits were produced in open field. But little attention has been given to soil properties with different culture facilities in organic grape cultivation. This study was conducted to investigate soil physico-chemical properties of organic grapes farms with different culture facilities and soil management practices. Organic fertilizer was main resource to manage soil at organic grapes farms. Organic grapes farms were applied with total amount of organic fertilizer at one time, either at basal or additional fertilization, whereas conventional grapes farms applied with split fertilization. Bulk density and penetration resistance of soil were lower at both rainshield and green manure-applied plastic greenhouse cultures than those at clean plastic greenhouse culture. Especially, in plastic greenhouse, sod culture with natural weed after green manure application was more effective than general sod culture in improving physical properties of the rhizosphere. The contents of organic matter, available phosphate and exchangeable potassium tended to increase in the soils applied with green manure, and the difference of soil chemical properties were significant between rainshield and plastic greenhouse cultures. The optimum soil management was required in plastic greenhouse because pH, available phosphate and exchangeable cations reached over optimum range. Consequently, the ground cover management is the key factor to affect the chemical properties as well as soil physical properties extensively in plastic greenhouse. It is found that sod culture with natural weed after green manure application resulted in enhancement of utilization efficiency of nitrogen, phosphoric acid and potassium in soil in comparison with general sod culture.

• 환경생물
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• 제34권1호
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• pp.48-55
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• 2016

본 연구는 자외선 광분해에 의한 비스페놀 A (BPA)의 에스트로겐 활성 저감에 미치는 하수처리장 방류수 유기물질의 영향을 조사하였다. 방류수 유기물질과 표준으로 사용한 스와니강 자연 유기물질은 극성에 따라 소수성, 반친수성, 친수성 분획으로 분리하였다. 특이 자외선 흡수 (SUVA) 분석 결과, 방류수 유기물질은 높는 소수성을 가지고 있는 자연 유기물질과 다르게 소수성이 낮은 미생물 기원 유기물질과 유사한 특성을 나타내었다. 3시간의 자외선 조사는 방류수 및 자연 유기물질의 극성에 따라 SUVA 값을 유의하게 감소시켰다 (p<0.0001). 유기물질이 없는 조건에서, BPA($5.0{\times}10^{-5}M$)의 상대 에스트로겐 활성도는 자외선 광분해에 의해 86%에서 63%로 감소하였다. 그러나 유기물질이 있는 조건에서 상대 에스트로겐 활성도는 평균적으로 68%에서 37%로 감소하였으며, 유기물질의 종류 (방류수 또는 자연유기물질) 및 극성 (소수성, 반친수성, 친수성)과 유의한 차이를 나타내지 않았다 (p>0.05). 결과적으로, 유기물질이 있고 없는 조건에서 자외선 광분해에 의해 감소한 BPA의 상대 에스트로겐 활성도는 각각 31%와 23%였으며, 이것은 방류수와 자연 유기물질 모두 광분해에 의한 BPA의 에스트로겐 활성 저감을 촉진시킨다는 것을 제시한다.

• 에너지공학
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• 제27권1호
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• pp.59-64
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• 2018

In this paper, we investigated the alternative sources of limestone. Oyster shell waste originated from aquaculture that causes a major disposal landfill problem in coastal sectors in southeast Korea. Their inadequate disposal causes a significant environmental problems araised. Bio mineralization leads to the formation of oyster shells and consists $CaCO_3$ as a major phase with a small amount of organic matter. It is a good alternative material source instead of natural lime stone. The utilization of oyster shell waste for industrial applications instead of natural limestone is major advantage for conservation of natural limestone. The present work describes the limestone and oyster shells hydraulic activity and chemical composition and characteristics are most similar for utilization of oyster shell waste instead of natural limestone.

• Asian-Australasian Journal of Animal Sciences
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• 제4권3호
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• pp.235-240
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• 1991

A CRD experiment with thirty growing cross bred calves were assigned at random to three treatments rations. 1) $T_0$, 0% Urea + 20% M. O. cake, 2) $T_1$, 1% Urea + 10% M. O. cake and 3) $T_2$, 2% Urea + 0% M. O. cake to develop a rice straw based ration for ruminants. Sweetish odour and yellowish colour were observed in good recovered silage. Organic matter varied from 87.45% to 89.63% whereas crude protein varied from 14.0% to 14.5% in each treatment. No significant differences were found among the nutrient composition of the ration. The dry matter in take (DMI) and dry matter digestibility was higher in $T_0$ (0% Urea) than those of ration containing 1% ($T_1$) and 2% Urea ($T_2$). The organic matter digestibility decreases with increasing doses of urea. The crude protein & nitrogen-free-extract digestibility were found higher in the ration $T_1$ containing 1% urea whereas crude fibre digestibility and available metabolizable energy (ME) were higher in $T_0$ containing no urea as compared to $T_1$ and $T_2$. Total digestible nutrient (TDN) decreases with the increase of urea level. The highest feed efficiency was found in $T_0$ having no urea and lowest was in $T_2$. The animals gained in weights from each ration. Highest gain in weight was found in $T_0$ ration, then followed $T_1$, and $T_2$. This is due to natural protein available in M. O. cake only. It is concluded that supplemetation of urea or M. O. cake with readily available energy source as molasses upto 20% of total dietary dry matter in a complete ration may increase the intake of low quality fibrous roughage only when nitrogen and mineral are not limiting factor.

• 한국토양비료학회지
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• 제30권1호
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• pp.72-83
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• 1997

Korean lespedeza의 자생지에 대한 작물의 생육상황, 작물에 함유된 무기영양상태, 자생지 및 자생지 부근의 토양의 화학 및 물리성에 관한 기초자료를 얻고져 총 46개 군락지역을 조사하였으며 얻은 자료를 분석한 결과는 다음과 같다. Korean lespedeza의 초장 및 건물중은 조사시기 및 지역에 따라서 큰 차이를 보여, 조사일이 늦은 8월 하순의 수치가 높았다. Korean lespedeza의 무기함량은 사료작물로서 가장 우수한 Alfafa에 비하여 Fe와 Mn함량은 많으나 P와 Zn함량은 비슷하였고, K, Ca, Mg, Cu등 함량은 적었다. Korean lespedeza의 자생지 토양을 우리나라 전체 토양과 자생지 부근의 농경지 밭토양과 비교하였을 때 자생지 토양의 화학적 특성은 pH와 Ca함량은 높은 반면, Mg함량은 비슷하였고, 유효 $P_2O_5$, 치환성K, OM의 함량은 낮았으며, 자생지 토양의 물리적 특성은 모래함량이 많은 대신 미사와 점토함량은 적었다. Korean lespedeza는 대체적으로 일반작물이 잘 자라지 못하는 물리-화학적 특성이 불량한 토양에서도 잘 자라며, 대체적으로 나지상태에 가까운 사양토나 양질사토에서 많이 자생하는 것으로 보아, 토양의 유실방지에 의한 토양보전에 큰 역할을 하고 있는 것으로 생각된다.

• 한국물환경학회지
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• 제25권5호
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• pp.697-703
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• 2009

In this study, changes in the composition of dissolved organic carbon (DOC) were investigated using water samples collected at a downstream site of the Namhan River near the Lake Paldang ($N37^{\circ}24^{\prime}05.33^{{\prime}{\prime}}E127^{\circ}32^{\prime}25.01^{{\prime}{\prime}}$) during a heavy rain event from July 23 to July 28, 2008. The DOC concentrations varied from 1.68 to 3.18 mg/L with the maxium value at a peak of the river water level. Each DOC sample was fractionated into three compositions including hydrophilic (Hi), hydrophobic acid (HoA) and hydrophobic neutral (HoN) fractions. The results showed that HoA was most abundant fractions, constituting 47.2~56.5% of DOC. Refractory dissolved organic carbon (R-DOC) contents were also determined by measuring the DOC concentration after 28-day dark incubation of the samples. R-DOC content was in the range from 83 to 99% of DOC and it was significantly correlated with HoA contents (r = 0.91, p<0.005), while it did not exhibit such a good correlation with the fractions of Hi and HoN (p>0.02). Our results suggest that the HoA, which is associated with humic substances, may be a major composition of refractory organic matters in rivers during storm events.

• 한국환경농학회지
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• 제42권4호
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• pp.338-345
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• 2023

Bacillus spp. and Saccharomyces spp. are effective microorganisms that are applied as microbial fertilizers for crops in Korea. Mixed organic fertilizer (MOF) has been used in the Korean organic agriculture to supply nutrients to crops. This study was conducted to investigate the effects of MOF containing Bacillus amyloliquefaciens HSOB-7 and Saccharomyces cerevisiae HSOB-8 (MOFBS) on the soil chemical properties and growth of lettuce (Lactuca sativa). Growth factors of lettuce were higher after applying different formulation types of MOFBS, such as powder and pellet, than those of NF, and not significantly different than those of control (microbe-free MOF). Compared with the control, application of recommended amount of MOFBS (MOFBS 250 kg/10a, MOFBS treatment) and double the recommended amount (MOFBS 500 kg/10a, 2MOFBS treatment) did not significantly change the growth factors of lettuce. After the application of two formulation types or two different amounts of MOFBS, soil chemical properties such as electrical conductivity, organic matter (OM), exchangeable Ca, and cation exchangeable cation (CEC) increased. These results indicated that although the application of MOFBS improved soil fertility including OM and CEC, it did not significantly affect lettuce growth.