Heavy metal contamination from abandoned mines presents long-term risks to soil ecosystems by altering physicochemical conditions and limiting microbial functions. To investigate these effects, we analyzed soils from the Deoksan Pb-Zn abandoned mine in Korea using community-level physiological profiling (CLPP) with Biolog EcoPlateTM. Soil samples were collected from three contaminated sites and one uncontaminated control, and we assessed their physicochemical properties, heavy metal concentrations, and microbial substrate utilization patterns over a 7-day incubation period. The results revealed significant site-specific differences in soil chemistry, with Zn and Pb concentrations exceeding ecological safety thresholds near the mine adit. Average well color development (AWCD) increased over time across all sites, but functional trajectories differed: highly contaminated soils exhibited prolonged increases, while low-contamination soils plateaued earlier. Substrate utilization patterns shifted over time, with carbohydrates and carboxylic acids dominating in the early incubation phase, while phosphorylated chemicals became more prominent in later stages. Multiple regression and relative importance analyses identified Cd, Pb, and Zn as key regulators of substrate utilization, with phosphorylated chemicals showing strong negative correlations (R 2>0.95). These findings indicate that heavy metal stress not only decreases overall microbial activity but also disrupts specific metabolic pathways. The utilization of phosphorylated chemicals emerged as a particularly sensitive functional indicator, underscoring its potential for ecological risk assessment and soil health monitoring in contaminated sites.

국내 고농도의 초미세먼지 발생 빈도 증가와 함께 그 전구물질인 NH3와 관련한 연구가 활발히 진행 중이다. NH3 배출에 있어 농업의 기여율이 높은 것은 자명한 사실이다. 그러나 비료 사용이 농경지 대기 중 NH3 농도에 장기간 미치는 영향에 관련한 연구는 미비한 실정이다. 따라서 본 연구에서는 수동식 NH3 확산형 포집기를 활용해 11개월 간 농경지 대기 중 NH3 농도를 관측하였다. 그 결과 비료 살포 직후 한 달 동안 NH3 배출의 영향이 가장 큰 것으로 나타났다. 그 이후 여름철 기온 상승으로 NH3 휘발이 촉진되어 대기 중 농도가 증가할 것으로 예상하였으나, 54일간의 지속적인 강우로 인하여 대기 중 높은 암모니아 농도는 관측되지 않았다. 그 후 NH3 농도는 가을과 겨울을 거치면서 점차 감소하였다. 비료의 영향력이 감쇠한 시점 이후에는 기온이 감소할수록, 그리고 강수량이 증가할수록 NH3 농도는 감소하는 것을 상관분석을 통해 확인할 수 있었다. 종합해 보면, 국내 NH3 배출량에서 비료의 기여율을 연구하는 데 있어 비료 살포 직후 최소 한 달 동안은 집중적으로 살펴보아야 할 것이며, 현장 연구 시 강수량과 무강우 일수 등의 기상 정보도 함께 고려해야 할 것이다.

Greenhouse gas emission from agricultural land is recognized as an important factor influencing climatic change. In this study, the national CO2 emission was estimated for paddy soils, using soil GHG emission model (DNDC) with 1 km2 scale. To evaluate the applicability of the model in Korea, verification was carried out based on field measurement data using a closed chamber. The total national CO2 emission in 2015 was estimated at 5,314 kt CO2-eq, with the emission per unit area ranging from 2.2~10.0 t CO2-eq ha-1. Geographically, the emission of Jeju province was particularly high, and the emission from the southern region was generally high. The result of the model verification analysis with the field data collected in this study (n=16) indicates that the relation between the field measurement and the model prediction was statistically similar (RMSE=22.2, ME=0.28, and r2=0.53). More field measurements under various climate conditions, and subsequent model verification with extended data sets, are further required.

In the last 10 years, the annual number of published journal articles on biochar has increased dramatically. In addition, biochar research in South Korea has received much attention in a variety of research fields. The objectives of this study were to determine biochar research trends using bibliometric analysis methods and to suggest future research directions in South Korea. The data used in this study were compiled from online international and domestic scientific articles from 2010 to 2015. Annual production, institutes, main journal titles, research fields and frequency of keywords were analyzed to assess current research trends. As a result, biochar research in South Korea was found to be initially 10 years behind the global trend, but in 8th place globally in terms of published articles as of 2015. Future research on the long-term ecological/environmental effects of land-applied biochar and factory-scale production systems is necessary to promote practical use of biochar in South Korea.

Land application of biochar (or charcoal) has increasingly been recognized due to its favorable effect as soil amendments. However, depending upon the nature of biomass and pyrolysis condition, biochar may be rich in hazardous inorganic elements. Giant Miscanthus showed its potential as a promising source for biochar manufacture but, the risk of heavy metal leaching from Giant Miscanthus-derived biochar (GMB) has not investigated. The objective of this study was to investigate the heavy metal leachability of GMB manufactured from 3 different temperatures (400, 500, and 700oC). Elemental composition of C, N, H, S, O and 18 metals were analyzed. Leaching concentration of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn was analyzed using 4 different methods (0.1 N HCl, 1 N NH4OAc, toxicity characteristic leaching procedure, and synthetic precipitation leaching procedure). For comparison, same analysis were performed for two char materials, municipal solid waste char (MWC) and sewage sludge char (SSC), manufactured from pilot-scale muncipal waste gasification plant. Elemental composition of GMB complied with the fertilizer guideline whereas the several heavy metal content (Cd, Ni, Pb, and Zn for MWC, Cr, Cu, Ni, and Zn for SSC) was beyond the criteria. From leaching test, concentration of heavy metals from GMB was positively increased with pyrolysis temperature and the acidity of extractant solution. Leaching concentration of plant nutrients (Ca, K, and Mg) was the highest by 1N NH4OAc. Meanwhile, leaching concentration of Cu from MWC and Pb from SSC exceeded the regulatory standard of Korea and US EPA, respectively. In conclusion, with respect to the risk of heavy metals, Giant Miscanthus-derived biochar will be suitable for land application as a soil amendment, while care should be taken for using municipal waste-derived char materials.