• 대한지하수환경학회지
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• 제1권2호
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• pp.80-84
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• 1994

토양중 중금속의 수직분포비율과 토양특성과의 관계를 규명하기 위하여 중금속에 의한 토양 오염이 우려되는 연· 아연 광산지역 주변농경지 27개 지점을 선정하여 토양깊이별로 시료를 채취하여 중금속함량과 토양의 이화학적 특성을 조사하였다. 본 연구를 통하여 얻어진 결과는 다음과 같다. 1) 중금속 원소의 토심별 분포는 표토(0- l5 cm)에서는 42-51%, 15 -30 cm에서는 21-29%, 30-60 cm에서는 12-17%, 60-100 cm에서는 11-14%였다. 2) 비소는 사양토와 양토간의 차이가 인정되나 Cd, Cu, Pb, Zn은 토성간에 차이가 없었다. 3) 토심별 각 원소의 함량분포비와 토양의 화학성과의 관계를 보면 각 원소 모두 pH와는 높은 유의성있는 부의 상관을 보인 반면 유의성있는 정의 상관을 나타내었다. 4) Cd, Cu, Pb 및 Zn 은 모든 토심에서 각 원소간에 대부분 높은 상관이 있었고 특히 Pb와 Zn은 0-15 cm, 30-60 cm, 60-100 cm에서 Cd와 Zn은 15 -30 cm에서 높은 상관을 나타내었다.

• 한국수자원학회논문집
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• 제47권10호
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• pp.945-958
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• 2014

토양온도는 비점오염과 관련된 수문학적 및 생지화학적 과정에 영향을 주는 중요한 물리적 환경인자 중 하나이다. 이 연구에서는 분포형 유역모델인 CAMEL(Chemicals, Agricultural Management and Erosion Losses)의 겨울철 토양온도 모의성능을 개선하기 위해서 융설과 토양 동결-융해 모델을 개발하였으며, 경기도 여주에 위치한 시험유역의 4개 지점에서 3개월 동안 관측한 토양온도 자료를 사용하여 모델을 보 검정하였다. 모의 결과, 표층 토양온도에 대해서는 모델이 토양온도의 시계열 변화를 비교적 잘 재현하는 반면($R^2$ 0.71~0.95, RMSE $0.89{\sim}1.49^{\circ}C$), 하부토양층 온도에 대해서는 경우에 따라 모델의 예측오차가 다소 크게 나타났는데($R^2$ 0.51~0.97, RMSE $0.51{\sim}5.08^{\circ}C$), 이것은 모델에서 토양 깊이별 토성을 동일한 것으로 가정한 것이 주요 원인인 것으로 판단된다. 한편, 개발된 모델은 융설에 의한 단열효과와 토양 동결-융해 과정에서 유입 또는 방출되는 잠열흐름의 영향으로 토양온도의 진폭이 감소하는 현상을 잘 모의하고 있다. 비록 모델 구조의 한계와 자료의 부족으로 토양온도에 대한 다소의 예측오차가 발생하였지만, 개발된 토양온도 모델은 시험유역의 토지이용 및 지형에 따른 토양온도와 적설상당수량의 시공간적 분포를 합리적으로 잘 모의하는 것으로 사료된다.

• 농업과학연구
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• 제38권4호
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• pp.631-639
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• 2011

This research was conducted to investigate potential use of New Zealand spinach (Tetragonia tetragonoides) as a new vegetable crop which will be cultivating in salt-affected soils including reclaimed land. Traditionally New Zealand spinach has been studied to explore functional compound or salt removing potential. To cultivate the crop species in the salt-affected soil widely, it is essential to obtain salt and soil texture responses under the controlled environment. Fifty nine New Zealand spinach ecotypes native to Korean peninsula first collected over seashore areas, and primitive habitat soil environment was evaluated by analyzing soil chemical properties from 32 locations. Different textures of sandy, silt loam, and sandy loam soils were prepared from nearby sources of sea shore, upland and paddy soils, respectively. Target salinity levels of 16.0 dS/m, 27.5 dS/m, 39.9 dS/m, and 52.4 dS/m in electrical conductivity (ECw) were achieved by diluting of 25, 50, 75, 100% (v/v) sea water to tap water (control, 0.6 dS/m), respectively. Various measurements responding to soil texture and irrigation salinity included plant height, root length, fresh weight (FW), dry weight (DW), leaf parameters (leaf number, leaf length, leaf width), lateral branching, and inorganic ion content. was found to adapt to diverse habitats ranging various soil chemical properties including soil pH, organic matter, exchangeable bases, EC, and cation exchange capacity (CEC) in Korea. Responding to soil texture, New Zealand spinach grew better in silt loam and sandy loam soil than in sandy soil. Higher yield (FW and DW) seemed to be associated with branch number (r=0.99 and 0.99, respectively), followed by plant height (r=0.94 and 0.97, respectively) and leaf number (r=0.89 and 0.84, respectively). Plant height, FW, and DW of the New Zealand spinach accessions were decreased with increasing irrigation salinity, while root length was not significantly different compared to control. Based on previous report, more narrow spectrum of salinity range (up to 16 dS/m) needs to be further studied in order to obtain more accurate salinity responses of the plant. As expected, leaf Na content was increased significantly with increasing salinity, while K and Ca contents decreased. Growth responses to soil texture and irrigation salinity implied the potential use of New Zealand spinach as a leafy vegetable in salt-affected soil constructed with silt loam or sandy loam soils.

• 한국토양비료학회지
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• 제49권3호
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• pp.275-281
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• 2016

The aim of this study was to examine the selected soil chemical properties of paddy fields in different topographic areas to efficiently manage nutrient valances of the paddy fields in Jeonbuk Province. Three-hundred soil sampling sites in paddy fields were selected from the different topographic areas in Jeonbuk Province. The soil samples were collected every four years from 1999 to 2015. Soil pH and exchangeable K and Mg concentrations declined during the experimental periods. However, almost all the chemical properties were within the proper levels for paddy soil, except exchangeable Mg concentration. Distributed areas of the paddy fields with soil pH below 5.5 continuously increased, but the paddy fields with lower concentrations of soil organic matter and available $P_2O_5$ than the proper levels declined after 2007. In addition, the paddy fields with available $SiO_2$ below the proper concentration decreased from 83.3% of the total paddy fields studied in 1999 to 61.0% of the total fields investigated in 2015. The paddy fields with lower exchangeable K and Mg than the proper levels increased after 2003 whereas the fields with lower exchangeable Ca concentration decreased. Dominant landform of coastal and plain areas was fluvio-marine plains that was distributed in 53.7% and 40.9%, respectively. Local valley and fans was a dominant landform of mountainous and middle-mountainous areas, which was 51.8% and 67.6%, respectively. Dominant soil textures distributed in coastal and plain areas were silty loam and loam. Those in mountainous and middle-mountainous areas were sandy loam and loam, respectively. Soil pH was relatively higher in coastal area and the comparatively higher content of soil organic matter was found in costal area than other areas. The concentrations of available $P_2O_5$, exchangeable Ca, and exchangeable Mg were generally higher in mountainous, coastal, plain areas, respectively, but available $SiO_2$ and exchangeable K concentrations were not significantly different among the different topographic areas.

• 한국토양비료학회지
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• 제44권5호
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• pp.696-701
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• 2011

전북지역 과수원 토양 110개소를 대상으로 토양특성이 미생물분포에 미치는 영향을 조사하였다. 토양 중 미사함량이 많아질수록 호기성세균, 곰팡이, 미생물 biomass C 함량은 증가하였고, 탈수소효소 활성은 토성에 따라 차이가 없었다. 지형에 따른 미생물분포, 미생물의 biomass C 함량, 탈수소효소 활성은 차이가 없었고, 과수종류에 따라 coliform group은 배와 포도 재배지에서 각각 $133.0{\times}10^3\;CFU\;g^{-1}$, $107.4{\times}10^3\;CFU\;g^{-1}$으로 가장 높은 수준을 보였다. 과수재배기간이 길어질수록 미생물 밀도는 감소하는 것으로 나타났다. 토양 pH, 유기물, 치환성 Mg 함량은 모든 미생물분포와 정의 상관관계를 보였고, Bacillus sp.는 조사한 모든 화학성분과 정의 관계를 보였다. 토양미생물의 biomass C 함량과 탈수소효소 활성은 유기물과 치환성 Ca 함량에 대해 고도의 유의성 (p<0.01)을 보였다.

• 한국토양비료학회지
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• 제49권6호
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• pp.795-806
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• 2016

This study was conducted to improve the continuous techniques for international competitiveness of ginseng industry to Korea-China FTA negotiation and conclusion, and provide the basic information for ginseng industry development of Korea. It was carried out the visiting of the northeastern three provinces (Jilin, Liaoling and Heilongjang) in China for 3-year from 2014 to 2016 and observed the farmers' fields of ginseng cultivation with soil environmental status. The types of ginseng cultivation could be observed in small scales of 0.5~3.0 ha, in middle scales of 4.0~10.0 ha and in large scales of 30~700 ha with the kinds of imhasam, Chinese ginseng, Korean ginseng and western ginseng. Also ginseng was cultivated in newly reclaimed land of forest in two types of direct seeding and transplanting of ginseng seedlings. The field beds of ginseng growing were covered with vinyl films in arch design of 100~130 cm height and vinyl was painted in spraying with blue, green and yellow colours for shading. It was investigated in status of the physico-chemical properties of soils. The physical information on the field soils were silt loam, loam and sandy loam in soil textures, and some plain in low slope, some alluvial fan or local valley in forest of land topography. Soil pH ranged within 5.0~5.2, soil EC was $0.93{\sim}3.78dS\;m^{-1}$, organic matter was $37{\sim}35g\;kg^{-1}$, nitrate nitrogen $63{\sim}490mg\;kg^{-1}$, available $P_2O_5$ $55{\sim}163mg\;kg^{-1}$, and in exchangeable cations, K was 0.30~0.98, Ca was 6.5~14.0, Mg was $1.1{\sim}5.3cmol_c\;kg^{-1}$ in ranges. Farmers used the fertilizer for ginseng cultivation in 10~11 t of compost, $200{\sim}400kg\;ha^{-1}$ of complex fertilizer and $750kg\;ha^{-1}$ of oil cakes. The northeastern three provinces of China can use the newly lands with large areas of ginseng cultivation in soil sickness by continuous cropping. and the soil basic fertility is batter than that of Korean in standard guide of ginseng cultivation soil.

• 한국환경농학회지
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• 제37권3호
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• pp.166-171
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• 2018

중량식 라이시미터를 활용하여 배추 재배 중 식양토와 사양토의 질소 용탈과 질소 수지를 평가하였다. 생육 초기인 9월 초 강우로 인해 식양토와 사양토 모두 토심 150 cm 이하로 배수가 있었다. 식양토는 점토의 수축 및 작물 뿌리 등에 의해 형성된 대공극을 통해 일시적으로 배수량이 증가하였으나, 사양토는 식양토와 달리 강우량에 따라 일정하게 배수량이 증가하고, 감소하였다. 토성별로 질소 용탈량을 분석한 결과, 식양토에서는 비료의 용탈이 거의 없는 반면, 사양토에서는 식양토에 비해 5배 많은 질소 용탈이 있었다. 질소수지에서 작물 흡수량에 비해 질소 용탈량이 차지하는 비율은 적었으나 식양토에 비해 사양토에서의 용탈량이 많아 질소 수지 산정에 토성에 따른 용탈특성을 고려할 필요가 있다.

• 한국잡초학회지
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• 제10권2호
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• pp.114-121
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• 1990

2,4-D의 제제(製劑)가 달라짐에 따라 다양(多樣)한 토양환경(土壤環境) 속에서 방출(放出)된 2,4-D 유효성분(有效成分)이 불활성화(不活性化)하는 속도와 식물(植物)에 흡수(吸收), 이행(移行)하는 속도간에 차이가 유발된 것임을 예상하고, 이들 차이를 검정식물의 생장반응으로 파악할 목적으로 일련의 시험을 하였다. 시험은 온실내에서 $30{\times}45{\times}13cm$ 의 4각폿트에 검정식물로 피(Echinochloa crus-galli)와 자귀풀(Aeschynomene indica)을 공시(供試)하여 수행하였으며, 40% 2,4-D amine salt [2,4-D/AS]와 19.7% complex of rice husk lignin/2, 4-Dichloropheoxy acetic acid [2,4-D/LG]를 200g ai/Ha로 처리(處理)하였다. 공시(供試)된 토양환경(土壤環境)으로는 시비량(施肥量), 토양산도(土壤酸度), 유기물시용량(有機物施用量) 및 토성(土性)으로서 기준토양(基準土壤)(check soil)을 포함하여 각각 3수준(水準)을 두고 3반복(反復)으로 수행(遂行)되었다. 시비량(施肥量)이 증대(增大)될수록 제초활성(除草活性)은 높고 오래 지속(持續)되었으며, 산성(酸性)이 강화(强化)되거나, 유기물(有機物) 시비량(施肥量)이 적을수록 제초활성(除草活性)이 높고 지속성(持續性)이 커지는 경향(傾向)이었다. 또한 전반 조건하에서 두 검정식물 모두 2,3-D/AS보다도 2,4-D/LG에 의하여 제초활성(除草活性)이 높고 장기간 지속(持續)되는 경향(傾向)임을 인정할 수 있었다. 그러나 토성(土性)에 따라서는, 제제간(製劑間)에 일정한 경향없이, 2,4-D/AS가 단기간(短期間)에 걸친 다양방출(多樣放出)로 식물흡수(植物吸收)보다 토양중에서의 불활성화가 크게 야기된는 반면, 2,4-D/LG는 장기간에 걸친 소량방출로 토양중불활성화(土壤中不活性化)보다 식물흡수기회(植物吸收機會)가 증대(增大)되는데 따른 것으로 해석된다.

• 한국농공학회논문집
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• 제56권3호
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• pp.31-38
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• 2014

Four actual cultivations were prepared and a variety of soybean was cultivated. A H-flume, an automatic water level gauge and an automatic water sampler were installed at the outlet of each plot equipped for the measurement of flow rate and its water quality. The amount of rainfall of the study area in 2013 was measured as 975.6 mm which was much lower than the annual average rainfall of 1,271.8 mm, resulting in less occurrences in rainfall-runoff events. Rainfall-runoff events were occurred three times during the rainfall event of 4~5 July, 23 and 24 August. The characteristics of NPS pollution discharge of the plots and the reduction effect of the selected BMPs were analyzed during these events. The reduction effect of straw mat and soil amendments (Polyacrylamide (PAM) and Gypsum) on runoff ratio ranged between 38.2 and 92.9% (average 71.6%). The NPS pollution load reduced between 27.7 and 95.1% (average 70.0%) by the application of rice straw mat and soil conditioner when compared with that of control plot. Soybean yield (2,133.3 kg/ha) of the straw mat covered plots increased by 14.3% when compared with control (1,866.7 kg/ha). The effect of straw mat on the yield was not economically viable if the material and accompanying labor costs were considered. The data collected and analyzed on different soil textures and crops in this study are expected to be a fundamental reference for the expansion of the results to the application nationwide and the development of NPS pollution management policies.

• 농업과학연구
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• 제46권4호
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• pp.857-868
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• 2019

A flooded rice field is one of the significant sources of anthropogenic methane (CH₄) with the intensity of the emissions dependent on management practices. Incorporation of rice straw, which is one of the organic amendments, induces the increase of methane emissions during the flooding season. In this study, we measured of methane emission according to applications of rice straw in different soil textures during a cultivation period in 2017 and 2018. The fallow treatments were non application of rice straw (NA), spring plowing after spring spreading of rice straw (SPSA), spring plowing after previous autumn spreading of rice straw (SPAA), and autumn plowing after previous autumn spreading of rice straw (APAA). The SPSA treatment emitted the highest total methane from loam soil in both 2017 (596.7 CH₄ kg ha^-1) and 2018 (795.4 CH₄ kg ha^-1). The same trend was observed in silt clay loam soil; the SPSA treatment still emitted the highest amount of methane in both 2017 (845.9 CH₄ kg ha^-1) and 2018 (1,071.7 CH₄ kg ha^-1). The lowest emission among the rice straw incorporated plots came from the APAA treatment for both soil texture types in all the seasons. The conversion factors of the SPAA were 0.79 and 0.65 from the loam and silt clay loam soils, respectively. Relatedly, the conversion factors of the APAA were 0.71 and 0.43 from the loam and silt clay loam soils, respectively. The above observations mean therefore that incorporation of rice straw early in the fallow reduces methane emissions in the main rice growing season.