• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.414-414
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• 2019

농업으로부터의 비점오염은 지표수와 지하수 모두의 수질에 영향을 미친다. 특히, 비료, 퇴비, 농약 등의 인공적 질소가 살포된 토양은 강우시 화학 침출로 인한 수질오염이 발생되고 있다. 강우시 강우유출수와 함께 지표 수역으로 흘러들어오는 영양물질(질소, 인)은 저수지로 유입되어 침수시 작물이 죽게 되어 저수지의 부영양화 등의 수질 오염문제를 야기시킨다. 국내에서는 홍수조절용지에서의 영농활동의 전면 금지하고 있는 실정이지만, 불법적으로 경작활동이 진행되고 있다. 따라서, 본 연구에서는 다목적댐 홍수조절지 내 경작지 토양 및 양분 특성 평가를 수행하였다. 홍수조절지 내 경작지 토양 특성 및 양분 조사를 위하여 경작이 집중적으로 이루어지고 있는 대청호 지역을 모니터링 지점으로 선정하였다. 모니터링은 경작지 내 토양 시료 및 주변 토양을 채취하여 분석을 수행하였다. 채취한 토양은 토양표준분석법(농촌진흥청, 2012) 및 농업토양분석방법(국립산림과학원, 2014) 기준을 바탕으로 물리 화학적 분석을 수행하였다. 모니터링은 2018년 5월부터 수행되었으며 현재까지 월 1회씩 모니터링을 진행하고 있다. 연구 결과, 밭 경작지 토양은 논에 비해 실트질 함량이 절반으로 침투성이 높은 토양으로 분석되었으며, 영양염류의 침투를 통한 이동 가능(기저유출)이 높게 나타나는 것으로 조사되었다. 이는 중간유출 및 기저유출 저감방안 도입이 필요한 것으로 평가되었다. 작물별 토양 양분분석 결과 고추, 마늘, 담배 경작지에서 화학비료사용량이 타 작물에 비해 높은 것을 분석되었으며, 경작지에 화학비료 및 퇴비의 과다 사용으로 염류농도가 증가할 경우 전기전도도가 높아지며 토양의 삼투압을 증가시켜 물의 흡수와 각종 양분 흡수를 방해하는 것으로 평가되었다. 인의 존재 형태별 비교시 대부분의 경작지에서 높은 값을 보였으며, 특히 경작지 토양의 Residual-P의 농도가 원지반 보다 2~5배 정도 높게 나타났다. 이러한 원인은 퇴비의 사용으로 인한 Residual-P의 누적으로 평가되며, 환경변화에 따라 수층으로 인의 용출이 쉽게 발생하므로 향후 수질에 미치는 영향이 더 클 것으로 사료된다.

• Journal of the Korean Geographical Society
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• v.43 no.3
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• pp.263-275
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• 2008

This Study deals with the comparative analysis on the estimation of surface soil erosion volume between South and North Korea using RUSLE model in Imjin River basin located on DMZ of Central Korea. Comparatively North Korea areas have been more eroded three times as much as South Korea parts. Because of cropland development such as com Held in the hillslope, in North Korea, more surface soil erosion and transportation to the river bed has given rise to frequent flood hazards. It seems that the study can dedicate to mitigation of environmental problems such as soil erosion and flooding in unaccessible Imjin River basin located on DMZ.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.1-7
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• 2016

This study focused on isolation and identification of wild yeasts from soils in fields near mountains and elucidation of its yeast distribution. Several kinds of yeasts were isolated from various soils of Daejeon metropolitan city and Chungcheongnam-do in Korea and identified by BLAST search of nucleotide sequences of internal transcribed spacer (ITS) region including 5.8S rRNA and D1/D2 region of 26S rDNA. Ninety-seven strains of 20 species from 61 soil samples were isolated, of which Cryptococcus podzolicus (11 strains), Debaryomyces hansenii (6 strains), and Trichosporon asahii (6 strains) were dominant species.

• Applied Biological Chemistry
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• v.24 no.3
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• pp.155-160
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• 1981

Residues of some organochlorine insecticides ${\alpha}-BHC$, ${\gamma}-BHC$, heptachlor and heptachlor epoxide of field soils and vegetables in Jeju island were investigated from october, 1979 to november, 1980. Residues in soil ranged in n.d-0.967 (aver.; 0.391) ppm for ${\alpha}-BHC$, n.d-0.590 (aver.; 0.218) ppm for ${\gamma}-BHC$, n.d-0.819 (aver.; 0.163) ppm for heptachlor, and n.d.-0.256 (aver.; 0.034)ppm for heptachlor epoxide. Average residue levels in cabbage were 0.002ppm for ${\alpha}-BHC$, 0.001ppm for ${\gamma}-BHC$, 0.002 ppm for heptachlor, and 0.001ppm for heptachlor epoxide. The levels of the same chemicals were 0.012ppm, 0.004ppm, 0.003ppm and 0.011ppm on carrot, and 0.014 ppm, 0.007ppm, 0.002ppm and trace on garlic, respectively.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.228-232
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• 1994

The influence of temperature, soil depth, burial duration, and soil moisture on the germination and viability of Galium spurium L. was studied in field and laboratory. Germination and maturing date were Oct. 20 and May 30, respectively. 1000 seed weight was 1.478g and seed color was dark brown. Optimum storage temperature to break dormancy was that $5^{\circ}C$, and germination rate of $10^{\circ}C$ was 81%, seed was not germinated at $20^{\circ}C$ or greater than $20^{\circ}C$. Optimum burial depth was 2cm and emergence rate was 40%. As bural duration in upland was longer, germination rate was increased, but buried seed of paddy land was died in a month. Optimum soil moisture content for germination was 25.3% in sand loam soil however seeds were not germinated above 43.6% or below 2.1%.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.426-426
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• 2015

무경운 농법은 경작지의 토양을 교란시키지 않고 작물을 재배하는 방법으로, 토양의 물리성 개선과 토양 침식 예방, 생산비 절감 등의 효과가 있어 전 세계적인 인정을 받고 있는 농업기술이다. 그러나 아직까지 무경운의 재배 지속 기간 등 많은 의문이 제기되고 있으며, 국내 환경조건에 맞는 실험적인 연구가 미흡한 실정이다. 이에 본 연구에서는 최적관리기법의 하나인 무경운(No-till)을 적용한 밭의 오염물질 저감효과를 장기적으로 살펴보고자 2011년부터 2014년까지 4년간의 모니터링을 실시하였다. 무경운 농법을 적용하기 위하여 동계피복작물(밀, 보리)을 재배작물 정식하기 전해 겨울에 파종하여 이듬해 6월 말 수확하였다. 이후 7월에서 8월 사이 재배작물(들깨, 무)을 정식하였다. 시비는 2011년에는 축산퇴비, 2012년에는 축산액비 그리고 2013년과 2014년에는 화학비료를 시비하였으며, 매년 경운과 무경운의 시비량은 동일하게 처리하였다. 유출 시험포의 면적은 $150m^2$(폭 5 m, 경사장 30 m)이며, 8개(경사도 3% 4개, 경사도 8% 4개)의 시험포를 조성하여 각각 2개씩 경운(관행)과 무경운을 적용하였다. 모니터링은 재배작물(들깨, 무) 정식 이후부터 작물 수확 전까지 강우사상에 대하여 이루어졌으며, 연구기간동안 총 13회의 강우 사상에 대하여 조사를 실시하였다. 경운대비 무경운 시험포의 평균 오염부하 삭감율을 분석한 결과 경사도 3% 시험포의 경우 BOD는 35.1%, $COD_{Cr}$은 37.4% 그리고 영양염류인 TN과 TP는 각각 36.9%와 33.5%가 삭감된 것으로 조사되었으며, 경사도 8% 시험포의 경우 BOD가 36.4%, $COD_{Cr}$은 45.8%, TN과 TP는 각각 45.5%와 40.6%가 삭감된 것으로 나타났다. 우리나라에서는 경운(관행) 농법이 영농관리 차원에서 대부분 이용되고 있으나, 본 연구 결과에 기초할 때 무경운 농법으로 영농할 경우 강우유출수 및 하천으로 유입되는 비점오염부하를 효과적으로 제어할 수 있을 것으로 기대된다.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.473-478
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• 2011

A wide diversity of liquid fertilizers and composts produced from the livestock manure in Korea is commonly applied to agricultural lands as an alternative of chemical fertilizers. However, their effects on the crop production and environmental impacts are still vague. The current study was conducted to understand the effects of the pig manure-based liquid fertilizer on the growth of Zea mays L. and soil properties. Four different liquid fertilizers were treated to each cultivated upland plot located in Gyeong-gi province, Korea while no fertilizer (control A) and a chemical fertilizer (control B) were treated to separate plots for comparison. The liquid fertilizer treatment did not make a significant difference in the fresh weight of Zea mays L. compared to the controls. This is probably due to the nutrient residues carried over from the last year fertilization. Electric conductivity (EC) and organic matter contents in soils were increased right after the liquid fertilizer treatments compared to the controls. However, soil pH was maintained as the same as the level of control A. A long-term effect of the continuous treatment of the manure based liquid fertilizer will be carried out in the successive study.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.532-538
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• 2014

Arsenic (As) is nonessential element toxic to plants. In Korea little is not only known about the extent of actual anthropogenic sources and inputs of arsenic to the agricultural land which plays a active role as a sink, but also systematic research on arsenic as an toxic element entering the food chain via the soil-plant pathway has not been investigated in the fields and greenhouses besides in few places of abandoned mining sites. Therefore, it is important to focus on the effect of As-contaminated soils on As uptake and biomass production of lettuce plants. In this study, As concentrations in the soil and accumulation of As in lettuce transferred by As uptake from soils were investigated. To do this, soil which was mixed with various rates of arsenopyrite gravels containing arsenic from 0 to 100% was packed into a round plastic pot. Then, 10 days old vegetable crops of chinese cabbage and lettuce after germination were transplanted into a pot. Growth of lettuce was observed for four weeks with one week interval. All experiments were done by triplicate. The results showed that the growth rates for number of leaves, width and length of the crop plants were retarded with increasing amount of gravel mixed due to increasing bioavailable amount of arsenate with increasing rate of gravel in soils. With these results, we conclude that the bioavailable amount of arsenate can influence the growth of lettuce.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.3
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• pp.185-191
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• 2001

To obtain the basic information for degradation of remaining pesticide accumulated in cultivated soil of Honam area, the resistant bacterial strains were investigated in Chlorothalonil(TPN). Mancozeb, Bentazone, and Butachlor levels of 100, $500{\mu}g\;ml^{-1}$, and degradation of TPN by TPN-resistant bacteria in sterilized soil was studied under TPN levels 0, 10, 50 and $100{\mu}g\;g^{-1}$. A number of resistance strains were decreased with higher at concentration level of pesticide, and were higher in greenhouse than upland or paddy soil. The resistance of bacteria was strong in other of Bentazone> Butachlor> TPN> Mancozeb. The percentage of bacterial strains of resistance for pesticides isolated from the cultivated soil were the highest in Acinetobacter spp. and Corynebacterium spp., and the lowest in Moraxella spp. A number of TPN-resistant strains were the highest at the TPN level of $10{\mu}g\;g^{-1}$, and 5 days after strains inoculation, and were higher in Pseudomonas spp. TD-25 than TC-23 or strains in non-sterilized soil. The degradation of TPN was fast in order of strain TD-25>strain in non-sterilized soil >TC-23.

• Korean journal of applied entomology
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• v.25 no.1 s.66
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• pp.47-51
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• 1986

A study was undertaken to investigate the distribution of Streptomyces spp. in soil in Korea. Among the different types of soil surveyed, the highest population of Streptomyces spp. recording $5.6{\times}10^5\;CFU/g$ was observed in upland soil. With reference to the soil depth, most of their population was distributed from soil surface to 5cm depth and the highest value was found in $0{\sim}2cm$ soil depth. Comparing the population of Streptomyces spp. with different soil color (by Munsell soil color chart), the highest value of $9.2{\times}10^\;CFU/g$ was showed in Oliver yellow soil (2.5Y, 6/4). On the basis of the acidity of soil samples subjected to Streptomyces spp. isolation, it is considered that the optimum pH range for Streptomyces spp. in soil lies between 6.0 to 7.5, showing the highest value of $1.05{\times}10^6CFU/g$ at pH 7.5. Among the colors of isolated colonies, gray and white colonies occupied 60% and 26% of the total isolates respectively.