• 자원환경지질
• /
• 제44권3호
• /
• pp.217-228
• /
• 2011

폐금속 광산인 삼광광산 주변 비소로 오염된 농경지 토양 복원을 위하여 5 종류의 안정화를 이용한 토양안정화 배치실험과 대형칼럼실험을 통하여 안정화제에 의한 토양 내 비소(As) 안정화 효율을 규명하고자 하였다. 오염 토양으로부터 주 오염원인 비소 용출을 최소화하여 수계로의 오염을 막기 위해, 안정화제로 석회, 석회석, 인회석, 황토, RMB(red mud bauxite)를 입상(2 ~ 5 mm)과 분말상으로 구별하여 용출배치실험에 사용하였으며, 오염토양 내 안정화제의 비율은 0, 0.1, 0.5, 1, 2, 5, 10 wt%로 설정하여 실험하였다 오염토양과 수용액의 비율을 1:10 으로 혼합한 실험의 경우, 2, 5 wt% 입상 석회 첨가에 의해 비소 용출이 각각 86, 95% 감소하였고, 5와 10 wt% 석회석 첨가의 경우에는 비소의 용출이 각각 82, 95% 감소하였다. 배치실험 결과로부터 비소 용출 저감 효과가 뛰어난 입상석회와 pH 증가가 적었던 입상석회석을 안정화제로 연속칼럼실험(지름 15 cm, 높이 100 cm인 아크릴칼럼 사용)을 실시하였다. 칼럼실험을 위해 오염토양 대비 첨가한 안정화제의 질량비는 석회의 경우 1 wt%와 2 wt%, 석회석의 경우 2 wt%와 5 wt%, 석회 1 wt%와 석회석 2 wt%를 사용하였고, 마지막으로 안정화제를 첨가하지 않은 오염토양만을 이용한 칼럼(총 6개 칼럼)을 반복 실험하였다. 칼럼실험결과 1 wt%와 2 wt% 석회를 첨가한 경우와 5% 석회석을 첨가한 경우 오염토양으로부터 비소 용출은 97% 감소하였으며, 1 wt% 석회와 2 wt% 석회석을 혼합하여 첨가한 경우에서도 97% 감소하였다. 배치실험 및 칼럼실험 결과, 비소로 오염된 삼광광산주변 농경지 토양을 대상으로 석회 및 석회석을 이용한 안정화 공법의 비소 저감 효율이 매우 높은 것으로 나타났다. 석회를 안정화제로 이용한 경우, 비소 안정화에는 높은 효율을 나타내었으나 용출액의 pH가 10이상으로 높게 나타나 식물의 생장 및 높은 pH에 따른 비소의 재용출을 야기할 가능성이 있는 것으로 나타났다. 반면 석회석을 안정화제로 이용한 경우 용출액의 pH는 8이하로 토양에 영향을 미치지 않았고, 석회와 비슷한 비소 저감 효율을 나타내어, 농작물 재배를 고려하는 농경지의 경우 비소로 오염된 토양의 안정화에는 석회보다 석회석이 더 뛰어날 것으로 판단되었다.

• 한국토양비료학회지
• /
• 제34권1호
• /
• pp.17-25
• /
• 2001

음식물쓰레기중 다량 함유된 식염은 음식물쓰레기 퇴비의 농업적 이용을 저해하는 가장 큰 요인으로 알려져 있으며, 본 연구는 농업적으로 안전하게 사용할 수 있는 음식물쓰레기 퇴비제조를 위하여 식염 함량이 낮은 부재료로 희석하는 방안을 시험하였다. 시험재료로 사용된 건조음식물쓰레기, 발표음식물쓰레기, 생음식물쓰레기는 생돈분, 톱밥, 왕겨 등과 혼합하여 $1m^3$ 규모로 퇴적하여 12주간 퇴비화하였다. 퇴비화과정중 온도, 탄질율, 암모니아가스 발생량을 주기적으로 조사하였고, 최종퇴비의 부숙도, 식물독성, 화학적 특성 등을 분석하였다. 탄질율은 퇴비화과정 동안 지속적으로 감소하였으나 최종/최초 탄질율의 감소는 크지 않았다. 퇴비더미의 온도와 6주째 암모니아가스 발생량을 고려할 때 모든 음식물쓰레기는 40일 전후에 퇴비화가 종료되는 것으로 판단되었고, 최종퇴비의 부숙도, 식염함량, 식물독성의 결과로부터 음식물쓰레기 종류별로 퇴비제조에 이용 가능한 몇 가지 배합비율을 선발하였다. 그러나 음식물쓰레기중 과다 함유된 식염을 희석하기 위하여 과량의 톱밥 또는 왕겨를 첨가한 때문에 최종 퇴비의 탄질비가 높고, 비료성분인 총 N-P-K 함량이 낮아 보다 양질의 음식물쓰레기 퇴비를 제조하기 위해서는 식염함량이 낮은 질소원 개발 또는 무기질 질소비료를 적절히 혼합하는 방안이 필요할 것으로 판단되었다.

• Journal of Applied Biological Chemistry
• /
• 제42권3호
• /
• pp.140-145
• /
• 1999

Livestock manure is generally beneficial to soil and crop production when appropriate amount is applied, but excessive application may be detrimental to soil and water environments. A proper protocol of livestock waste treatment is required to manage the quality of soil and water. A trickling filter system using rice straw media was employed to treat piggery wastewater from small-scaled livestock farms as an alternative to the currently available methods. Batches of piggery wastewater were treated with this system, and the byproducts of rice straw media and trickling filtrate were applied to the soil with cultivating rye (Secale cereale L.). Objective of this research was to characterize these byproducts for the sustainable soil amendments and rye production. Both the treated straw medium and filtrate were proven to be effective organic fertilizers for rye plant development, with the enhanced but balanced absorption of nutrients. The synergistic effects of filtrate in addition to straw application did not show, but the filtrate appeared to lead to a higher water content of the plant. No specific nutrient deficiency or toxicity symptom was shown due to the salts derived from the byproducts applied. Chemical parameters of the soil quality were significantly improved with the application of straw medium either with or without the filtrate. Judging from parameters relating to the salt accumulations, such as sodium adsorption ratio (SAR), electrical conductivity (EC), exchangeable sodium percentage (ESP), potassium adsorption ratio (KAR), and residual P concentrations, the byproducts from piggery wastewater exhibited no detrimental effects on soil quality within the ranges of treatments used. In addition to the effectiveness of the rice straw trickling filter system for the small-scaled swine farms, both rice straw medium and filtrate could be recycled for the sustainable soil amendment and plant nutrition.

• 한국근적외분광분석학회:학술대회논문집
• /
• 한국근적외분광분석학회 2001년도 NIR-2001
• /
• pp.1615-1615
• /
• 2001

During the past ten years, Near Infrared Spectroscopy has been successfully applied to the analysis of a great variety of agriculture products. Previous works (Morra et al., 1991; Salgo et al., 1998) have shown the potential of this technology for soil analysis, estimating different parameters just with one single scan. The main advantages of NIR applications in soils are the speed of response, allowing the increase of the number of samples analysed to define a particular soil, and the instantaneous elaboration of recommendations for fertilization and soil amendment. Another advantage is to avoid the use of chemical reagents at all, being an environmentally safe technique. In this paper, we have studied a set of 129 soil samples selected from representative glasshouse soils from Southern Spain. The samples were dried, milled, and sieved to pass a 2 mm sieve and then analysed for organic carbon, total nitrogen, inorganic nitrogen (nitrate ammonium), hygroscopic humidity, pH and electrical conductivity in the 1:1 extract. NIR spectra of all samples were obtained in reflectance mode using a Foss NIR Systems 6500 spectrophotometer equipped with a spinning module. Calibration equations were developed for seven analytical parameters (ph, Total nitrogen, organic nitrogen, organic carbon, C/N ratio and Electric Conductivity). Preliminary results show good correlation coefficients and standard errors of cross validation in equations obtained for Organic Carbon, Organic Nitrogen, Total Nitrogen and C/N ratio. Calibrations for nitrates and nitrites, ammonia and electric conductivity were not acceptable. Calibration obtained for pH had an acceptable SECV, but the determination coefficient was found very poor probably due to the reduced range in reference values. Since the estimation of Organic Carbon and C/N ratio are acceptable NIIRS could be used as a fast method to assess the necessity of organic amendments in soils from Mediterranean regions where the low level of organic matter in soils constitutes an important agronomic problem. Furthermore, the possibility of a single and fast estimation of Total Nitrogen (tedious determination by modifications of the Kjeldahl procedure) could provide and interesting data to use in the estimation of nitrogen fertilizer rates by means of nitrogen balances.

• 한국유기농업학회지
• /
• 제25권4호
• /
• pp.805-819
• /
• 2017

The study was carried out to develop a mathematical model for evaluating the effect of organic fertilizers in organic rice production systems. A function to simulate the nitrogen mineralization process in the paddy soil has been developed and integrated into ORYZA2000 crop growth model. Inorganic nitrogen in the soil was estimated by single exponential models, given temperature and C:N ratio of organic amendments. Data collected from the two-year field experiment were used to evaluate the performance of the model. The revised version of ORYZA2000 provided reasonable estimates of key variables for nitrogen dynamics and crop growth in the organic rice production systems. Coefficient of determination between the measured value and simulated value were 0.6613, 0.8938, and 0.8092, respectively for soil inorganic nitrogen, total dry matter production, and rice yield. This means that the model could be used to quantify nitrogen supplying capacity of organic fertilizers relative to chemical fertilizer. Nitrogen dynamics and rice growth simulated by the model would be useful information to make decision for organic fertilization in organic rice production systems.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제11권6호
• /
• pp.1-7
• /
• 2006

본 연구는 토양오염 관련정보를 DB화하고 관리할 수 있는 효율적인 정보관리체계구축 방안을 제시하기 위하여 국 내외 정보관리체계 현황을 분석하고 국내 문제점을 파악한 후 정보관리체계 구축을 위한 정책적 시사점을 도출하고자 하였다. 외국사례 및 국내 현황을 살펴본 결과, 1) 정보관리 및 정보공개에 대한 선언적 조항을 '토양환경보전법'에 추가, 2) 정화단계별 세부규정 및 지침서 개발, 3) 정보의 전자화, 4) 정보관리주체 일원화, 5) 주민참여 및 정보공개제도 개선 등을 법제도적으로 보완할 필요가 있었다. 이러한 결과를 바탕으로 후속연구인 두 번째 연구에서는 국내적용 가능한 정보체계 구축(안)을 설정하고 이를 뒷받침하기 위한 정책적 제안을 제시할 예정이다.

• 한국토양비료학회지
• /
• 제48권4호
• /
• pp.271-277
• /
• 2015

Anaerobic decomposition of organic material in flooded rice fields produces methane, which escapes to the atmosphere primarily by transport through the rice plants. The annual amount of $CH_4$ emitted from a given area of rice is a function of the number and duration of crops grown, water regimes before and during cultivation period, and organic and inorganic soil amendments. Soil type, temperature, and rice cultivar also affect $CH_4$ emissions. The field experiment was conducted for three years to develop methane emission factor for water regime before the cultivation period from the rice fields. It was treated with three different water regimes prior to rice cultivation, namely: non-flooded pre-season < 180 days, non-flooded pre-season > 180 days, flooded per-season in which the minimum flooding interval is set to 30 days. Methane emission increased with days after transplanting and soil redox potential (Eh) decreased rapidly after flooding during the rice cultivation. The average methane emission fluxes were $5.47kg\;CH_4\;ha^{-1}day^{-1}$in flooded pre-season > 30 days, 5.04 in non-flooded pre-season < 180 days and 4.62 in non-flooded pre-season > 180. Methane emission flux was highly correlated with soil temperature and soil Eh. Rice yields showed no difference among treatments with water regime before the cultivation period.

• 한국지하수토양환경학회지:지하수토양환경
• /
• 제26권1호
• /
• pp.8-16
• /
• 2021

This study has evaluated the stabilization of As contaminated paddy and cultivated soils by pot experiments for rice and lettuce. Various ratios of limestone (L) and steel slag (S) were mixed with the soils in each pot. The soils were taken from before and after pot experiments, and analyzed for As extracted by sequentially (Wenzel method) and totally (aqua regia method).. Paddy soils amended with L (0.5%) and L (1.0%) + S (1.0%) showed increasing fraction 2 (specifically bound As) compared with control soil. Arsenic concentrations in rice grain grown on the amended soils decreased 14% and 12% compared with those on the control soil, respectively. According to sequential extraction of As in cultivated soils, the fractions 1~3 were decreased due to stabilization of As by the soil amendment, especially for S (1.0%), S (3.0%) and L (1.0%) + S (1.0%). In addition, relatively low As concentrations were found in lettuce grown on amended soils with L (0.5%) and L (1.0%) + S (1.0%). Therefore, it can be suggested that soil amendments with L (0.5%) or L (1.0%) + S (1.0%) were suitable for enhancing stabilization of As in the study area.

• 한국환경농학회지
• /
• 제41권4호
• /
• pp.223-229
• /
• 2022

BACKGROUND: Mining activities, smelter discharges, and sludges are the major sources of heavy metal contamination to soils. The objective of this study was to determine the efficiency of magnetite and bottom ash derived from coal ash in remediating As-contaminated soil. METHODS AND RESULTS: An incubation experiment was conducted for 10 weeks. Magnetite and bottom ash at different rates and ratios were applied to each plastic bottle repacked with 1,000 g of dried As-contaminated soil. After 3-weeks of incubation, the concentrations of available As were measured by using Mehlich-3, SBET, and sequential extraction methods. All of the subjected soil amendments resulted in significant decreases in available As concentration compared to the controls. The addition of magnetite at the highest rate was the best to stabilize As in the soils; however, the values of As concentration varied with the extraction methods. CONCLUSION(S): To ensure the stabilization accuracy of heavy metals in soil, both single and sequential extractions are recommended. The magnetite derived from fly coal ash can also be applicable as a heavy metal stabilizer for the As-contaminated soil.

• 한국산림과학회지
• /
• 제101권3호
• /
• pp.405-411
• /
• 2012

경상남도 진주시와 산청군에 위치한 성숙한 밤나무 재배지를 대상으로 여러 가지 토양 개량제 처리[(유기질비료 처리구: 20 kg/본; 복합비료 및 목탄 처리구: 복합비료 4 kg/본+목탄 2 kg/본; 석회비료 처리구: 3 kg/본; 혼합비료 처리구: 복합비료 1 kg/본+유기질비료 10 kg/본+목탄 1 kg/본; 대조구(무시비구)]가 토양 특성 및 잎 형질에 미치는 단기적 영향을 조사하였다. 밤나무 재배지에 토양용적밀도, 토양 유기탄소, 전 질소, 칼슘 및 마그네슘 함량은 양 개량제 처리에 따른 유의적인 변화가 없었다. 그러나 잎 건중량은 진주지역 석회비료 처리구($0.65\;g\;leaf^{-1}$), 산청지역 유기질비료 처리구($0.68\;g\;leaf^{-1}$)로 대조구(진주: $0.46\;g\;leaf^{-1}$; 산청: $0.53\;g\;leaf^{-1}$)에 비해 유의적으로 높았다. 잎면적의 경우 진주지역 석회비료 처리구가($79.1\;cm^2\;leaf^{-1}$)로 가장 크게 나타났으며, 산청지역 토양 개량제 처리구는 ($70.4\;cm^2\;leaf^{-1}{\sim}78.2\;cm^2\;leaf^{-1}$)로 대조구(진주: $56.2\;cm^2\;leaf^{-1}$; 산청: $60.5\;cm^2\;leaf^{-1}$)에 비해 유의적으로 증가하였다. 토양 개량제 처리에 따른 잎 내 질소 함량은 혼합비료 처리구가 2.51%, 복합비료+목탄 처리구가 2.50%로 대조구 .98%에 비해 유의적으로 높았다. 본 연구 결과에 따르면 토양 개량제 처리는 밤나무 재배지의 단기적인 토양 특성개선에는 효과가 크지 않았으나 잎 형질 개선에 효과가 있었으며, 잎 내 질소 분석은 밤나무 재배지의 토양 개량 효과를 판정할 수 있는 지표로 나타났다.