• Review Article

    Analysis of Research Trends in Nitrous Oxide Emissions from Upland in Korea
    Sun-Il Lee, Chang-Kyu Lee1, Gun-Yeob Kim, Hyo-Suk Gwon, Jong-Sik Lee, Eun-Jung Choi, and Joung-Du Shin
    Global climate change, especially global warming is considered as threat to our future and posterity. Increasing concentrations of greenhouse gas such as ... + READ MORE
    Global climate change, especially global warming is considered as threat to our future and posterity. Increasing concentrations of greenhouse gas such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are the main causes of global warming. The Korean government has set a goal to cut the carbon emissions by 37% based on business-as-usual levels by 2030. According to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), agricultural sector is an important source of greenhouse gas emissions. In this regard, it is common belief that reducing of such emission is of great significance to global climate change. In Korea, upland is one of the main sources of agricultural N2O emission. In order to analyze domestic research trends related to N2O emissions in the upland, 53 academic publications from 2009 to September 2019 were critically reviewed. The results were classified according to the research purposes. Reduction technologies of N2O emission account for approximately 28.3%. N2O characteristics and assessment for 24.5%, development of N2O emission factors for 22.6%, and N2O inventory assessment for 20.8% etc. Biochar, green manure, no tillage, and inhibitor were studied as a means of reducing N2O release. The optimum technologies to reduce N2O emission in Korea were discussed and proposed through the previous researches. Main mitigation measures for nitrous oxide emission. Mitigation measures Mitigation effects Data source Adding biochar 24.6% Seo et al., 2012 -23.8% to 41.4% Park et al., 2014b 16.4% to 20.6% Kim et al., 2014c -24.6% to 48.3% Park et al., 2015 12.3% to 39.3% Park et al., 2016b -74.0% to -9.0% Lee et al., 2017b 31.9% to 48.1% Lee et al., 2017a 81.8% to 86.9% Lee et al., 2018b Adding green manure 19.2% to 71.3% Kim et al., 2011b 38.6% Seo et al., 2012 4.7% to 17.6% Yoo et al., 2015 -17.0% to -3.8% Yoo et al., 2016 44.9% to 56.2% Kim et al., 2018a No tillage 7.3% to 62.4% Kim et al., 2011b 15.2% to 28.6% Yoo et al., 2015 5.7% to 35.7% Yoo et al., 2016 Adding inhibitor 18.4% to 78.5% Ju et al., 2018 Adding slow release fertilizer 56.2% to 64.3% Kim et al., 2018a Water management 13.2% to 40.2% Kim et al., 2014a - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Replacement Ratio of Mixed Oilcake for Basal Application of Inorganic Fertilizers in Watermelon Cultivation at the Plastic Film House Soil
    Myung Sook Kim, Seong Jin Park, Sung Hyun Kim, Hyun Young Hwang, and Seok Cheol Kim
    The objective of this study was analyzed the replacement ratio of mixed oil cakes(MC) for basal application of inorganic fertilizers. The ... + READ MORE
    The objective of this study was analyzed the replacement ratio of mixed oil cakes(MC) for basal application of inorganic fertilizers. The fields were selected the plastic film house soils for watermelon cultivation. The MC were applied at 50(MC50+N50), 100(MC100), and 150(MC 150) % level of the basal amount of nitrogen fertilizer in soil testing recommendation. And these were compared to NPK treatment and -N(PK) treatment except nitrogen as inorganic fertilizer. The yields of watermelon in MC50+N50, MC100, and MC150 were similar to NPK treatment, but sugar contents as watermelon quality in MC50+N50, MC100, and MC150 were higher than NPK. In MC100 and MC150 treatments, nitrate nitrogen and electrical conductivity were lower than MC50+N50 treatment. Relative nitrogen efficiency of watermelon ranged 109 - 128%. These results suggest that MC application with the 100 - 150% level of nitrogen input as the basal dressing could be best to prevent a nutrient accumulation of soil and to increase the yield and commercial quality for watermelon. Changes in watermelon yield according to replacement ratio of basal amount of nitrogen fertilizer. ( ) mean relative yield of watermelon to NPK treatment. N, P, K, and MC mean nitrogen, phosphate, potash fertilizers, and mixed oil cakes, respectively. Treatment Fruit weight (g plant-1) Sugar contents (Brix) Weight of leaf, stem, and fruit (ton ha-1) -N (PK) 5,312(78)b† 10.0b 45.1b NPK 6,768(100)a 10.1b 58.0a MC 50+N50 6,866(101)a 11.1a 58.6a MC 100 6,963(103)a 11.5a 61.1a MC 150 6,960(103)a 11.7a 63.7a † Numbers with the same letter within a column are not significantly differed (Duncan's test, p < 0.05). - COLLAPSE
    November 2019
  • Short Communication

    Weighable Lysimeter Study for Water Balance Estimation of Chinese Cabbage in the Fall Season
    Jung-hun Ok, Kyung-hwa Han, Yong-seon Zhang, Hee-rae Cho, Seon-ah Hwang, and Dong-Jin Kim
    In this study, we estimated and compared the water balance and total water requirement for Chinese cabbage cultivation in the fall season ... + READ MORE
    In this study, we estimated and compared the water balance and total water requirement for Chinese cabbage cultivation in the fall season using weighable lysimeters. The water balance of input and output were investigated according to by two different upland soils. In Chinese cabbage cultivation, the total input was different in precipitation and irrigation, and total output was different in evapotranspiration and drainage. The estimated total water requirement for Chinese cabbage cultivation in the fall season in 2017 and 2018 were lower as compared to that in normal years (1981 - 2010) because of large amount rainfall around transplanting in 2017 and several rainfall events in 2018. The total water requirements for normal years, 2017, and 2018 were 147.2 mm, 143.6 mm, and 135.5 mm, respectively, compared to the normal years, it decreased by 2% in 2017 and by 8% in 2018. The weighable lysimeter has provided a useful tool for the water balance and water requirement estimation of Chinese cabbage and could be developed for several crops in upland condition based on obtained data. The water balance for Chinese cabbage cultivation in the fall season on different upland soils using weighable lysimeters in 2017 and 2018. Water balance Water management NIR† IR SiCL† SL SiCL SL 2017 (Sep. 4. - Oct. 31.) Input (mm) Effective precipitation 137.8 136.1 135.4 136.9 Irrigation 13.7 13.9 61.1 60.4 Total 151.5 150.0 196.5 197.3 Output (mm) Drainage 36.7 7.9 56.0 58.6 Evapotranspiration 196.1 203.3 202.2 224.4 Runoff 0.0 0.0 0.0 0.0 Total 232.8 211.2 258.2 283.0 Changes in soil water storage (mm) -81.3 -61.2 -61.7 -85.7 2018 (Aug. 31. - Oct. 30.) Input (mm) Effective precipitation 165.7 163.6 157.1 165.2 Irrigation 4.4 4.6 4.5 4.5 Total 170.1 168.2 161.6 169.7 Output (mm) Drainage 58.9 3.6 65.3 14.0 Evapotranspiration 208.5 210.4 185.7 177.9 Runoff 0.0 0.0 0.0 0.0 Total 267.4 214.0 251.0 191.9 Changes in soil water storage (mm) -97.3 -45.8 -99.4 -22.2 †NIR, not irrigated after rooting stage; IR, irrigated by furrow irrigation. †SiCL and SL indicated silty clay loam and sandy loam in soil texture of surface soil, respectively. - COLLAPSE
    November 2019
  • Short Communication

    Changes of Soil Chemical Quality Index of Paddy Soils by Long-term Application of Soil Amendments
    Myung Sook Kim, Seong Jin Park, Sung Hun Kim, Hyun Young Hwang, Song Heui Ahn, Dong Won Lee, and Yun hae Lee
    Soil is an essential resource for life and its properties are susceptible to be modified by application of soil amendment. The impact ... + READ MORE
    Soil is an essential resource for life and its properties are susceptible to be modified by application of soil amendment. The impact of management practices on soil function can be assessed through a soil quality index. The changes in soil chemical quality index in paddy soils applied of soil amendments were assessed from data of long-term experiment plots which were operated from 1969 to 2016 by the National Institute of Agricultural Science, Wanju, Korea. The treatments were inorganic fertilization (NPK), inorganic fertilizer plus soil amendments (rice straw compost, NPK+C; silicate fertilizer, NPK+S; mixing rice straw compost and silicate fertilizer, NPK+CS). The quality index of soil for chemical properties was analysed by method suggested by Yoon et al. (2004) which calculating soil quality index integrating the score of the each soil chemical property and divided into by 4 periods (Period Ⅰ: 1969 - 1978, Period Ⅱ: 1979 - 1985, Period Ⅲ: 1986 - 2001, Period Ⅳ: 2002 - 2016). The paddy fields for the long-term experiments were changed to a soil with good quality under application of soil amendment over a period of time. The order of magnitude of soil chemical quality index was NPK+CS > NPK+S > NPK+C > NPK. Chemical attributes such as pH, SOM, and Av.SiO2 increased the soil quality index in NPK+C, NPK+S, and NPK+CS compared to NPK. The quality index of soil chemical properties of NPK, NPK+C and NPK+S treatments ranged from 70 to 74 in period, from 64 to 71 in period Ⅱ, and to 75 to 82 in period Ⅲ and Ⅳ. Especially, the decrease of the chemical quality index value of NPK, NPK+C and NPK+S treatments in Period Ⅱ was attributed to the decrease of the soil pH value below the optimum range of rice growth due to irrigation water. The NPK+CS treatment increased to the highest value of 87 in period I, but tended to decrease slightly at period Ⅲ and Ⅳ. It showed that these were caused by the accumulation of silicate fertilizer, resulting in a decrease of the chemical quality index value of the soil. When a constant amount of soil amendments was continuously applied for 48 years, the soil chemical quality index were improved. After that period, the soil chemical quality index, however, was decreased because of excess accumulation of soil amendments. In view of the soil chemical quality index values, optimal application of soil amendment is the most suitable management for this site since it preserves soil quality and provides an acceptable rice grain yield. Changes of score of soil chemical quality index by periods in a paddy soil by long-term application of inorganic fertilizers and soil amendments. Period NPK NPK+C NPK+S NPK+CS Starting year ('54) 34 34 34 34 Period I (69 - 79) 67 72 77 87 Period II (80 - 89) 63 66 77 81 Period III (90 - 02) 67 69 82 78 Period IV (03 - 16) 75 77 80 80 - COLLAPSE
    November 2019
  • Short Communication

    Consideration of Suffix Symbol on Soil Taxonomy and World Reference Base for Soil Resources Classification
    Yeonkyu Sonn, Byunghwan Seo, Woori Go, Sangho Jeon, Byungkeun Hyun, and Sungang Yun
    There is a difference between ST and WRB in distinguishing the master horizon. When a pedologists investigate a soil profile, it is ... + READ MORE
    There is a difference between ST and WRB in distinguishing the master horizon. When a pedologists investigate a soil profile, it is difficult to determine which classification method to choose including the master horizon, add a prefix, suffix, etc. to the horizon name. The suffix symbol for groundwater level uses ‘g’ for ST and ‘l’ or ‘r’ for WRB. The suffix symbol ‘r’ represents a strong reduction state, and ‘l’ is used in a state where oxidation is much progressed. However, in the real agricultural field, the groundwater level is lowered so that the oxidized part of the profile is classified based on < 2%, 2 - 20%, > 20%. In addition, there are soils with a mottle quantity of 20 to 49%. ST classifies this as one like ‘g’, and WRB distinguishes it. However, since only the presence of a mottle is determined, a refinement is required. The proposals of mottle amounts 'r' in ST & WRB. Present Proposals Mottle quantity ST WRB Mottle quantity ST WRB few (< 2%) g l few (< 2%) g l common (2 - 20%) r common (2 - 20%) r many (≥ 20%) many (≥ 20%, < 50%) - COLLAPSE
    November 2019
  • Short Communication

    Establishment of GHGs Emission Reduction Evaluation Methodology on Land Use Change of Paddy Field from Rice to Upland Crop Cultivation
    Jong-Sik Lee, Gun-Yeob Kim, Eun-Jung Choi, Sun-Il Lee, A-Ran Kim, Dong-Kyun Jeong, Hyun-Kyu Park, and Gil-Zae Lee
    This study was conducted to evaluate the effect of GHGs emission reduction with land use change of paddy field. For this we ... + READ MORE
    This study was conducted to evaluate the effect of GHGs emission reduction with land use change of paddy field. For this we developed the evaluation methodology to calculate the GHGs emission reduction from land. At first, procedure of ETS (emission trading system) methodology on land use change of paddy field was developed. Second, system boundary for each land use was defined. Finally, evaluation methodology on GHGs emission reduction was established. The amounts of GHGs emission reduction on land use change of paddy field was evaluated as difference between baseline emission (BE) and project emission (PE). The system boundary of BE were ① CH4 emission from anaerobic decomposition of organic material in rice field (BECH4), ② N2O emission from N fertilizer application (BEN2O), and ③ CO2 emission from farming machine use (BECO2). Those of PE were ① N2O emission from N fertilizer application (PEN2O) and ② CO2 emission from farming machine use (PECO2). At the evaluation on PE, methan emission was excluded, which was generated usually at anaerobic condition of paddy. Emission amounts of each gas was converted as carbon dioxide with multiplying global warming potential (GWP). Evaluation methodology on GHGs emission reduction on land use change of paddy field. Factor Calculating formula for GHGs emission Baseline Emission (BE) BE = BECH4 + BEN2O + BECO2 ① CH4 emission from anaerobic decomposition of organic material in rice field BECH4 = A × EFCH4 × GWPCH4 ② N2O emission from N fertilizer application BEN2O = A × EFN2O × GWPN2O ③ CO2 emission from farming machine use BECO2 = A × EFCO2 Project Emission (PE) PE = PEN2O + PECO2 ① N2O emission from N fertilizer application PEN2O = A × EFN2O ×GWPN2O ② CO2 emission from farming machine use PECO2 = A ×EFCO2 Emission Reduction (ER) ER = BE ‑ PE GWP : Global Warming Potential, A : cultivation area (ha), EFCH4 : methane emission factor from rice field (kg CH4 ha-1yr-1), EFN2O : nitrous oxide emission factor with N fertilizer application (kg N2O ha-1yr-1), EFCO2 : carbon dioxide emission factor with farming machine use (kg CO2 ha-1yr-1) - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of the Uniformity and Distribution of Water Spray Due to Type of Lay Flat Sprinkler Hose and Pumping Pressure
    Sangho Jeon, Kyunghwa Han, Byungkeun Hyun, Yeonkyu Sonn, Woori Go, and Byunghwan Seo
    Lay flat sprinkler hoses are widely use in S. Korea due to its reasonable price and flexibility. However, it applies a lot ... + READ MORE
    Lay flat sprinkler hoses are widely use in S. Korea due to its reasonable price and flexibility. However, it applies a lot of water for a short time in a field that potentially causing unbalanced irrigation. In addition, there have been not many studies on characteristics such as irrigation uniformity. In this regards, the purpose of this study was to provide fundamental data for the design and operation of lay flat sprinkler by evaluating the irrigation uniformity and the watering pattern according to the change of water pressure. The most important characteristics for the uniformity were a pattern, number, and diameter of the holes on the lay flat sprinkler hoses. The amount of irrigation was different up to 2.3 times under the same (or about same) water pressure. Statistical uniformity (CV) of the sprinkler hose A, B, C showed good to fair, good, and fair respectively. Emission uniformity (EU) of the sprinkler hose A, B, and C classified good, excellent to good, and fair individually. The results of this study would be useful for proper water management by providing fundamental data such as water pressure level, spacing, and water management when installing lay flat sprinkler hoses in crop cultivating sites. These figures show perforation pattern and interval on lay flat sprinkler hose. These Patterns, interval, and holes’ diameter are critical characteristics for Irrigation uniformity. - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Gyeonggi Province
    Ahn-Sung Roh, Jung-Su Park, Young-Su Park, Ok-Jung Ju, Min-Woo Shin, Min-Kyeong Kim, and Soon-Kun Choi
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeonggi Province over a ... + READ MORE
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeonggi Province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis of the study sites revealed that the mean chemical oxygen demand was 3.8 mg L-1, with the median values being 3.5 mg L-1. The mean chemical oxygen demand in April, July, and October were 4.7, 3.8, and 3.1 mg L-1, respectively, and chemical oxygen demand values trended to decrease from April to October. The mean and the median electrical conductivity were 0.22 dS m-1. The mean electrical conductivity values were slightly higher in April and lower in October, and there was no yearly fluctuation. The mean and median values of the T-N (Total Nitrogen) content were 3.3 mg L-1 and 3.0 mg L-1, respectively. The mean and median values of the T-P (Total Phosphorous) content were 0.10 mg L-1 and 0.06 mg L-1, respectively, and there was no tendency to increase or decrease during the April, July and October. Changes in annual water quality index in April (left), July (center), and October (right). - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Watershed in Gyeongbuk Province
    Kwang Seop Kim, Jun-Hong Park, Hye-Jeong Jeong, Jong-Soo Kim, So-jin Yeob, Seung-Oh Hur, and Soon-Kun Choi
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeongbuk province over a ... + READ MORE
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeongbuk province over a 5-year period ranging from 2013 to 2017. The results of water quality analysis revealed that the mean chemical oxygen demand was 3.6 mg L-1, with the median values being 3.3 mg L-1. The mean and median values of electrical conductivity (EC) were 0.24 dS m-1 and 0.23 dS m-1, respectively. The mean and median values of the total nitrogen (T-N) content were 2.6 mg m-1 and 2.4 mg m-1, respectively. The mean and median values of the total phosphorous (T-P) content were 0.12 mg m-1 and 0.11 mg m-1, respectively. EC and T-P contents had increased as the area ration of agricultural land increased, although there were no statistically significant differences. The trend of T-N content was reversed. Therefore, further researches are needed to evaluated contribution of artificial pollution such as livestock as well as change in flow rate. Changes in precipitation and Chemical Oxygen Demand (CODMN) in April, July, and October. - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Gyeongnam Province
    Jae-Young Heo, Hyeon-Ji Cho, Young Han Lee, So-Jin Yeob, and Seung-Oh Hur
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeongnam province over a ... + READ MORE
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Gyeongnam province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis of the study sites revealed that the mean chemical oxygen demand was 3.0 mg L-1, with the median values being 2.7 mg L-1. The mean and median values of the electrical conductivity were 0.19 dS m-1 and 0.18 dS m-1, respectively. The mean T-N (Total Nitrogen) content was 2.43 mg L-1, with the median values being 2.00 mg L-1 and the mean and median values of the T-P (Total Phosphorous) were 0.07 mg L-1 and 0.04 mg L-1, respectively. T-N and T-P concentrations were slightly different yearly and monthly, but there was no tendency to increase or decrease. Changes in annual water quality index in April, July, and October. - COLLAPSE
    November 2019
  • Short Communication

    Changes in Agricultural Stream Water Quality of Small Watershed in Gangwon Province from 2007 to 2016
    Ki Yeon Lee, Soo Young Hong, Byeong Sung Yoon, Su Jeong Heo, Byeong Gon Choi, Eun Ha Jang, Dae Ki Hong, Min Kyeong Kim, and Soon-Kun Choi
    This study aimed to identify the changing pattern in the agricultural water quality of the small watersheds in Gangwon province over a ... + READ MORE
    This study aimed to identify the changing pattern in the agricultural water quality of the small watersheds in Gangwon province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis of the study sites revealed that the mean chemical oxygen demand was 1.9 mg L-1, with the median values being 1.7 mg L-1, and there was no yearly fluctuation. The mean and median values of electrical conductivity (EC) were 0.17 dS m-1 and 0.13 dS m-1, respectively, and the values trended to increase from April to October. The mean and median values of the total nitrogen (T-N) content were 2.83 mg L-1 and 2.50 mg L-1, respectively. The mean and median values of the total phosphorous (T-P) content were 0.05 mg L-1 and 0.02 mg L-1, respectively. The T-N and T-P content were the highest in April during the survey period, 3.08 mg L-1 and 0.06 mg L-1, respectively. Changes in annual water quality index in April, July and October in Gangwon province. - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Chungbuk Province
    Chung-Woo Kim, Ji-Yoon Yoo, Min-Ja Kim, Young-Ho Kim, So-Jin Yeob, and Soon-Kun Choi
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Chungbuk province over a ... + READ MORE
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Chungbuk province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis of the study sites revealed that the mean chemical oxygen demand was 3.1 mg L-1, with the median values being 2.8 mg L-1. The mean chemical oxygen demand in April, July, and October were 2.9, 3.5, and 2.8 mg L-1, respectively. The mean chemical oxygen demand values were lower in April and October and slightly higher in July. The mean value of electrical conductivity was 0.19 dS m-1, and there was no yearly fluctuation. The mean and median values of the Total Nitrogen (T-N) content were 4.2 mg L-1 and 3.4 mg L-1, respectively. The mean and median values of the Total Phosphorous (T-P) content were 0.07 mg L-1 and 0.04 mg L-1, respectively, and there was a trend of increasing from 2014 to 2016. Changes in annual water quality index in April, July, and October. - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Jeonnam Province
    Sung-Woo Kim, Sun Kook Kim, Hyeon Ji Kim, So Yeon Lee, Myeong Seok Kim, Jeong-Hwa Kang, Seung-Oh Hur, and Soon Ik Kwon
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Jeonnam Province over a ... + READ MORE
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Jeonnam Province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis of the study sites revealed that the mean Chemical Oxygen Demand in April, July, and October was 3.20, 3.04, and 2.37 mg L-1, respectively, with the median values being 2.85, 2.84, and 1.96 mg L-1, respectively. The mean values of EC (Electrical Conductivity) in April, July, and October were 0.15, 0.15, and 0.17 dS m-1, respectively. The mean EC values were lower in April and slightly higher in October, and there was no yearly fluctuation. The mean and median values of the T-N (Total Nitrogen) content were 3.41 mg L-1 and 3.18 mg L-1, respectively. A large deviation in the T-N content was only observed in April 2009 and July 2015. The mean and median values of the T-P (Total Phosphorous) content were 0.09 mg L-1 and 0.05 mg L-1, respectively. No fluctuations were observed in the T-P content in the months of April, July, and October, during the study period, with the exception of July 2016 and October 2016. Changes in annual water quality index in April, July, and October. - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Jeonbuk Province
    Do-Young Ko, Byung-Koo Ahn, Tae-Bok Kim, Hyo-Jung Cho, Hyong-Gwon Chon, Soon-Kun Choi, and Seung-Oh Hur
    This study was conducted to investigate the trend of water quality fluctuations for 10 years (2007 - 2016) in the river waters of ... + READ MORE
    This study was conducted to investigate the trend of water quality fluctuations for 10 years (2007 - 2016) in the river waters of rural watershed in Jeonbuk Province. The average of CODMn in the study area was 4.17 mg L-1 and its median 3.47 mg L-1. EC averaged 0.22 dS m-1, its median was 0.19 dS m-1, and increased to October. The total nitrogen (T-N) content averaged 2.74 mg L-1, its median 2.40 mg L-1, and the total phosphorus (T-P) content averaged 0.09 mg L-1 and its median 0.07 mg L-1. The highest T-N content was 2.76 mg L-1 in April and the average T-P content was maintained at 0.09 mg L-1 during the investigated period. Changes in annual water quality index in April, July and October. - COLLAPSE
    November 2019
  • Short Communication

    Evaluation of Changes in Agricultural Stream Water Quality of Small Watershed in Chungnam Province
    Yeo-Uk Yun, Jin-Il Lee, So-jin Yeob, and Soon-Kun Choi
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Chungnam Province over a ... + READ MORE
    This study aimed to identify the changing trends in the agricultural water quality of the major watersheds in Chungnam Province over a 10-year period ranging from 2007 to 2016. The results of water quality analysis revealed that the mean chemical oxygen demand was 4.1 mg L-1, with the median values being 4.0 mg L-1. The result of annual CODMn of stream water showed tendency to increase. The mean and median values of EC (electrical conductivity) were 0.21 dS m-1 and 0.19 dS m-1, respectively. The mean T-N (total nitrogen) was 2.91 mg L-1, with the median values being 2.47 mg L-1. The mean and median values of the T-P (total phosphorous) content were 0.11 mg L-1 and 0.07 mg L-1, respectively. Changes in annual water quality index in April, July, and October. - COLLAPSE
    November 2019
  • Article

    Relationship between Soil Chemical Properties and Algae Growth at Rice Paddy Field
    Hui Su Bae, Seung Hyeon Ahn, Jaebok Hwang, Hyeonsoo Jang, Jong Tak Youn, Uk Han Kim, Tae Seon Park, and Beomsoo Bae
    Influences of various soil chemical properties on the algae growth (Chl-a concentration) at the paddy field were statistically analyzed using soil and ... + READ MORE
    Influences of various soil chemical properties on the algae growth (Chl-a concentration) at the paddy field were statistically analyzed using soil and water samples collected from 2016 to 2018 in June. As a result of correlation analysis between soil chemical properties and Chl-a concentration, significantly positive relationships were observed in pH, EC and SiO2. To identify the key soil chemistry variables and predict Chl-a concentration, factor analysis was done and three principal components (PCs) with eigenvalues > 1 were found, which accounting for 60.9% of the original variance. The PC1 included Mg2+, Ca2+ and Avali.-P. The PC2 included pH, Na+, K+, and Avail.-SiO2. PC3 included OM and T-N. According to the result of linear regression analysis based on the factors by factor analysis, the total explanation amount was 18.0% and only PC3 had an significant influence on the decrease of Chl-a concentration. These result will be used for soil management to prevent algae blooms at rice paddy field. Rotated factor pattern matrix between chemical properties of soil and chlorophyll-a at rice paddy field. Indicators Component PC1 PC2 PC3 Mg2+ 0.837 0.180 0.171 Ca2+ 0.769 0.263 0.198 Avail.-P2O5 -0.713 0.251 0.180 EC 0.566 0.545 0.113 pH -0.018 0.783 -0.093 Na+ -0.047 0.637 0.126 K+ 0.370 0.506 0.330 Avail.-SiO2 0.274 0.560 -0.005 OM -0.056 -0.072 0.847 T-N 0.222 0.161 0.813 Eigenvalue 3.3 1.4 1.4 Proportion (%) 33.1 14.1 13.6 Cumulative (%) 33.1 47.3 60.9 - COLLAPSE
    November 2019
  • Article

    Transition Characteristics and Risk Assessment of Heavy Metal(loid)s in Angelica gigas Nakai and Cnidium officinale Makino
    Da-Young Kim, Da-In Kim, Yeung-Jin Seo, Soon-Kun Choi, Kwon-Rae Kim, Kye-Hoon Kim, Oh-Kyung Kwon, and Won-Il Kim
    This study was conducted to identify transition characteristics of heavy metal(loid)s and to assess dietary risk in the Angelica gigas ... + READ MORE
    This study was conducted to identify transition characteristics of heavy metal(loid)s and to assess dietary risk in the Angelica gigas and Cnidium officinale grown at the major medicinal plant producing districts in Korea. Average bio-concentration factor (BCF) values and range were 0.056 (0.006-0.511) in arsenic (As), 2.030 (0.021-15.678) in cadmium (Cd), 0.179 (0.052-0.393) in mercury (Hg), and 0.061 (0.013-0.474) in lead (Pb) in Angelica gigas. Average BCF values and range were 0.044 (0.011-0.264) in As, 0.557 (0.052-4.255) in Cd, 0.174 (0.069-0.286) in Hg, and 0.024 (0.012-0.057) in Pb in Cnidium officinale. The BCF values by heavy metal(loid)s in Angelica gigas and Cnidium officinale were high in Cd, copper (Cu) and zinc (Zn), while As and Pb were found to be less transferable. The BCF values calculated in this study will be useful for predicting the uptake of heavy metal(loid)s. Human exposure to As, Cd, Hg, and Pb through dietary intake of Angelica gigas and Cnidium officinale might not cause adverse health effects although some Angelica gigas were higher than the allowable value for Cd. Further study on uptake and accumulation mechanism of Cd by Angelica gigas is required to assess the human health risk associated with soil contamination. Mean and maximum value of HQ and CR for As, Cd, Hg and Pb concentrations in Angelica gigas and Cnidium officinale grown at the major producing districts in Korea. Cultivated Crops Hazard quotients (HQ) Cancer risk (CR) As Cd Hg Pb Total Angelica gigas 3.04 × 10-2 (9.63 × 10-2)† 6.17 × 10-3 (2.17 × 10-2) 3.12 × 10-4 (1.05 × 10-3) 7.22 × 10-3 (4.26 × 10-2) 4.41 × 10-2 (1.62 × 10-1) 1.37 × 10-5 (4.33 × 10-5) Cnidium officinale 1.27 × 10-2 (3.91 × 10-2) 3.45 × 10-3 (1.22 × 10-2) 2.35 × 10-4 (3.37 × 10-4) 2.18 × 10-3 (6.12 × 10-3) 1.85 × 10-2 (5.77 × 10-2) 5.71 × 10-6 (1.76 × 10-5) †Maximum value of HQ. - COLLAPSE
    November 2019
  • Article

    Growth Stage-Based Fertigation Guideline for Greenhouse Spring Chinese Cabbage
    Seul-Bi Lee, Yang-Min Kim, Ye-Jin Lee, Yo-Sung Song, Deog-Bae Lee, and Jwakyung Sung
    With increasing fertigation, the precise fertigation schedule by crop growth stage has been consistently required as a guideline for stable crop production ... + READ MORE
    With increasing fertigation, the precise fertigation schedule by crop growth stage has been consistently required as a guideline for stable crop production. The aim of this study is to develop the fertigation guideline for spring cabbage. To achieve this goal, we firstly investigated the nutrient uptake pattern of Chinese cabbage, which grown in pots filled with sandy loam soil in a greenhouse from April to June in 2018, and determined optimal nutrient (N, P and K) supply by growth stages. Based on soil NO3-N based recommendation, nitrogen (N) supply was divided into 4 levels (0.5N, 0.75N, 1.0N and 1.5N). Soil NO3-N concentrations somewhat differed from growth stages, and 1.5N represented the highest level. Chinese cabbage showed linear growth patterns and there was no clearly significant difference in growth and nutrient uptake by N supply levels except for 0.5N treatment. The relative growth (expressed as a dry weight) of Chinese cabbage occupied 60% and 40% of total accumulated growth (average of 0.75 and 1.0N) at 40 and 60 days, respectively. Mineral uptake (N, P, K) of Chinese cabbage by growth stages showed a linear pattern in general. N was taken up 54% and 46% of total uptake, P uptake 56% and 44%, and K uptake 59% and 41% at 40 and 60 days, respectively. Conclusively, we carefully suggest that the fertigation guideline for Chinese cabbage could save fertilizer supply through daily nutrient demand and target yield, and thus alleviate the problems in relation to nutrient accumulation in greenhouse soils. Weekly fertigation scheduling (g 10a-1) of N, P2O5 and K for greenhouse spring Chinese cabbage. Fertilization level was estimated based on mineral uptake, nutrient use efficiency and target yield (1 Mg 10a-1, FW). Growth stages Weeks after transplanting Cultivation : early April ~ late June Plant density : 4,000 plant 10a-1 N P2O5 K2O Early stage 1 - - - 2 - - - Leaf elongation 3 210 120 345 4 210 120 345 5 210 120 345 6 210 120 345 Heading 7 330 200 650 8 330 200 650 9 330 200 650 Total requirement 1,830 1,080 3,330 - COLLAPSE
    November 2019
  • Article

    Isolation and Characterization of Phosphate Solubilizing Pseudomonas Species and Their Effect on Plant Growth Promotion
    Gyeong Seo Jo, Sang Yoon Kim, Ju Sik Cho, and Yong Hwa Cheong
    Plant growth-promoting rhizobacteria (PGPR) affect plant growth via various direct or indirect mechanisms. These microorganisms are the potential tools for sustainable agriculture ... + READ MORE
    Plant growth-promoting rhizobacteria (PGPR) affect plant growth via various direct or indirect mechanisms. These microorganisms are the potential tools for sustainable agriculture. In this study, eight different Pseudomonas strains (PM1 - PM8) isolated from rhizospheric soil were characterized plant growth-promoting characteristics, including indole-3-acetic acid (IAA) and Gibberellin (GA3) production, phosphate solubilization, 1- aminocyclopropane-1-carboxylic acid (ACC) deaminase activity and effects of direct inoculation on plant growth parameters (fresh weight, shoot length). All of these strains have their ability for solubilization of insoluble phosphate depending on pH decrease at the range around pH4 - 5 at 2 days after inoculation. PM1, PM4, PM5 and PM7 species was capable of IAA production and PM4, PM5, PM7 and PM8 species have high activity for production of gibberellin (GA3) hormone. For ACC deaminase activity, PM1, PM3 and PM8 show high activity. Furthermore, all these species have significantly promoted the growth of the lettuce seedling plants for fresh weight and shoot length enhancement, so that these Pseudomonas species could be used as potential bio-fertilizer agents. Production of plant hormone IAA (A) and GA3 (B) from isolated Pseudomonas species. - COLLAPSE
    November 2019
  • Article

    Effect of Organic Amendments on Rice Yield and Soil Carbon Fraction in Paddy Soil
    Hyeon-Suk Cho, Myung-Chul Seo, Jun-Hwan Kim, Wan-gyu Sang, Pyeong Shin, and Jaekyeong Baek
    In agricultural land, organic matter plays an important role in crop productivity by improving the physical properties of soil and supplying nutrients ... + READ MORE
    In agricultural land, organic matter plays an important role in crop productivity by improving the physical properties of soil and supplying nutrients to plants. In this study, field experiment was carried out to assess the effect of three organic amendments, [HV(Hairy vetch), OCC(Oil Cake Compost), LMC(Livestock Manure Compost)] on paddy rice growth and soil carbon fractions. According to a survey of early rice growth after using organic amendments, there were 34.6 - 37.9 cm in plant height and 11.3 - 14.9 in number of panicles per plant, which was not different between the types of organic amendment and control rice growth and yield at the harvest were better in organically amended-plot that in the control. Based on growth parameters as affected by organic amendments, rice growth was better in the order of OCC > HV > LMC > Control. The number of panicle per m2 was 591, which was 1.5 - 1.7 times higher than that of other organic amendment, and about twice as high as that of the control. However, the percentage of ripened grain (76.5%) and the 1000-grain weight of brown rice (21.0 g) were lower than other organic amendment application. Rice yield was much better in oil cake compost (5.9 ton ha-1) than in other organic amendment treatments. Soil carbon content increased in all organic amendment application after the test. T-C content was high in OCC and lower in HV and LMC. The carbon content of each type was the largest with the Humin carbon content and the similar amount of humic acid carbon and fulvic acid carbon content. The proportion of soil carbon fraction was about about 59 - 67% of humin carbon, 13 - 23% of fulvic acid carbon content and 19 - 26% of humic acid carbon. In conclusion, in view of rice yield and soil carbon, it is suggested that organic amendment can be advantageous to paddy soil and oil cake compost was considered potential resources as alternative chemical fertilizer. The rice yield and soil carbon(T-C) content by different organic amendment during the harvest season. - COLLAPSE
    November 2019
  • Article

    Effects of Wood-derived Biochar Application on Soil Chemical Properties and Growth of Lettuce (Lactuca sativa L.)
    Yun-Sook Yi, Hyeon-Ji Cho, Jae-Young Heo, and Young Han Lee
    Biochar is an amendment that can be used for reducing odors, enhancing crop productivity and soil fertility to revitalize the urban agriculture ... + READ MORE
    Biochar is an amendment that can be used for reducing odors, enhancing crop productivity and soil fertility to revitalize the urban agriculture. The objective of this study was to evaluate the effects of biochar from the pyrolysis pine on the soil chemical properties, nutrient uptake, and growth of lettuce plants (Lactuca sativa L.) in an upland field. Lettuce was planted in an silt loam soil amended with four rates of biochar 0 (CFB1), 60 (CFB2), 120 (CFB3), and 240 kg 10a-1 (CFB4) with chemical fertilizer (14.3 kg 10a-1 N, 15.7 kg 10a-1 P2O5, and 12.1 kg 10a-1 K2O), no fertilizer (NF), and animal compost 440 kg 10a-1 with chemical fertilizer (CFC). Leaf number and fresh weight of lettuce plant were higher in CFB4 treatment than in the other treatments. Increasing rates of biochar caused a significant increase in lettuce yield, amount of nutrient uptake, and soil pH. The economically optimum application rate of fertilizer biochar was 200 kg 10a-1 on the basis of the regression curve. The electrical conductivity of the CFB1 soil was significantly higher than in the other treatments, whereas the soil pH was significantly lower in the CFB1 soil than those in the biochar treatments and NF soils. These results showed that biochar amendment increased yield of crops as well as improving soil properties. A regression curve between yield of lettuce and application rate of wood-derived biochar. - COLLAPSE
    November 2019
  • Article

    Optimal Levels for Nutrient Diagnosis of Crops and On-Site Application: Dry- or Water Soluble-Based Leaf Analysis
    Ye-Jin Lee, Seul-Bi Lee, and Jwakyung Sung
    It is one of most important works to recognize the nutritional status of crops for promoting best nutrient management. Furthermore, a rapid ... + READ MORE
    It is one of most important works to recognize the nutritional status of crops for promoting best nutrient management. Furthermore, a rapid and accurate diagnosis of mineral nutrients is strongly required at agricultural on-site. Here, we described the optimal range for favorable crop growth and development based on the results of previous researches performed since 1990 in NAS, RDA, and focused on explaining analytical method and optimal range of water soluble-based N, P and K for greenhouse crops. Water soluble mineral N, P and K differently responded with leaf position and crop; overall, soluble N was higher in fully expanded leaves, soluble P was relatively higher young leaves and soluble K constantly remained in all leaves. Given the results, water soluble mineral nutrients of greenhouse crops showed relatively higher in Solanaceae (e.g. paprika and eggplant) than in Cucurbitaceae (e.g. cucumber and watermelon). In this respect, the nutrient management in terms of fertilization and crop uptake is necessary to make crop-specific strategy. Although the criteria for nutrient diagnosis based on water soluble extracts was described in this paper, we carefully suggest that better criteria for nutrient diagnosis should be advanced with consideration for diurnal pattern of water soluble minerals, difference in sample destruction degree, duration of storage of samples taken, and etc. Relative Classification by the concentration of mineral nutrients of crops. Analysis Cultivation Concentration Crops Dry weight-based Upland Moderate ~ High Potato, Pepper, Water melon, Spinach, Radish Low ~ Moderate Sweet potato, Cabbage, Leek, Garlic, Onion, Carrot Greenhouse Moderate ~ High Pepper, Water melon, Oriental melon, Lettuce, Young radish Low ~ Moderate Cucumber, Tomato, Cherry tomato, Strawberry, Green pumpkin, Cabbage, Kale, Radish Water soluble-based Greenhouse Moderate ~ High Paprika, Eggplant, Green pumpkin, Pepper Low ~ Moderate Tomato, Strawberry, Cucumber, Watermelon, Melon - COLLAPSE
    November 2019
  • Article

    Mineralogical Characteristics and Physico-Chemical Properties of a Newly Reclaimed Tidal Flat of Haenam Bay in the Southwestern Coast of Korea
    Kyo S. Lee, Jin-Hee, Ryu, Dong-Sung Lee, Beong-Deuk Hong, Il-Hwan Seo, Chul-Soon Lim, Hyun-Kyu Jung, and Doug-Young Chung
    The aim of this investigation was to identify the soil physical and chemical properties and the mineralogies of recently reclaimed tidal flat ... + READ MORE
    The aim of this investigation was to identify the soil physical and chemical properties and the mineralogies of recently reclaimed tidal flat land (RTFL) consisted of five different soil series within the investigation site located in Youngsan-river Bay of Southwestern coast in Korea, that has to be only used as upland according to the policy of designated absolute agricultural land. The results show that the soil textures of the soil horizons are sandy loam and silt loam for all five soil series, with typical soil colors of yellow to pale yellow for Ap horizons containing higher clay content greater (> 18%) and greenish gray containing higher sand content (> 60%). The pHs of surface horizons for Bokchun (BC), Junbook (JB) and Poseung (PS) soil series are not only acidic (< 4.5) but also soil color is dark brown with reddish brown mottles. The X-ray diffraction (XRD) analyses represent the major minerals are illite, kaolinite and quartz for BC, JB and PS soil series while quartz and illite are major minerals for Taehan (TH) and Gwangpo (GP) soil series. Silicon and aluminum dominant in the Ap and Bg horizons are significantly higher in the soil series of BC, JB and PS than those in TH and GP. Also, we found that the kaolinite particles of varying sizes are arranged in face-to-face patterns along with the presence of spherical particles of quartz, especially in BC, JB and PS. Index map and Locations of soil profile investigation pits and soil sampling points for five soil series within the experimental site at the RTFS within the Haenam Bay. Numerous dendritic streams on the wide tidal flat and main tidal channel (maximum depth of 25 m) comprise the coastal embayment. - COLLAPSE
    November 2019
  • Article

    Root Growth and Spatial Distribution Characterization of Soybean (Glycine max L.) and Adzuki Bean (Vigna angularis L.) Under Drought Stress
    Hyen Chung Chun, Ki Yuol Jung, Young Dae Choi, Sanghun Lee, and Hang Won Kang
    Recently Korea has severe drought during sowing and early vegetative period of soybean and adzuki bean cultivation. Soybean and adzuki bean are ... + READ MORE
    Recently Korea has severe drought during sowing and early vegetative period of soybean and adzuki bean cultivation. Soybean and adzuki bean are an important legume crops in Korea, so it is important to understand adaptation of these crops to water stress. This study investigated changes of morphological properties and spatial distribution of soybean and adzuki bean roots under different soil moisture contents. The experiment was performed at National Institute of Crio Science in Miryang. Soybeans and adzuki beans were planted in a test tube with 40 in length, 20 in width, and 4 cm in depth and grew for 20 days. The tubes were filled with turface soil with six soil moisture treatments (30, 40, 50, 60, 70 and 100%). The root images were obtained every 2 days using a scanner. Root properties from the images were characterized by root length, depth, surface area, number of roots and fractal parameters (fractal dimension and lacunarity). The root depth, length, surface area and number of roots increased as soil moisture increased from both crops. The values of fractal dimension and lacunarity increased as soil moisture increased. These results indicated that greater soil moisture induced more heterogeneous root structure. Correlation analysis among morphological properties and fractal parameters resulted in that the fractal dimension had the greatest correlation with depth, number of roots and surface area from soybean. Lacunarity from soybean showed a greater correlation with number of roots and surface area than ones from adzuki bean. This result indicates that fractal dimension is strongly related to branching of roots. Soybean and adzuki bean are sensitive to soil moisture content in early vegetative stage and they require soil moisture greater than 70% to develop full root structure. These results would be useful to understand soybean and adzuki bean responses to water stress and to manage irrigation amounts in cultivation. Example root images of soybean and adzuki bean with no water stress after planting (DAP –days after planting). - COLLAPSE
    November 2019
  • Article

    Contamination Indices and Heavy Metal Concentrations in Urban Garden Soil of Busan Metropolis
    Jin-Suk Kwag, Gab-Je Cho, Mi-Eun Jeong, Kwang-Yong Ju, Bok-Joo Song, and Dong-Choon Ryou
    To identify the concentrations of heavy metals and to assess soil environmental quality 29 soil samples were collected from Urban area (UA ... + READ MORE
    To identify the concentrations of heavy metals and to assess soil environmental quality 29 soil samples were collected from Urban area (UA) and Suburban area (SA) in Busan, Korea. An assessment was conducted using soil pollution index (SPI) and geoaccumulation (Igeo) in order to establish the concentration of heavy metal. Accumulation of heavy metals in urban vegetable soils are affected by multiple factors including soil properties and climatic conditions. The concentration of Cd, Cu, As, Hg, Pb, Cr6+, Zn, and Ni were found to be greater in soils more than the background. The geoaccumulation map revealed index of geoaccumulation (Igeo) beyond class 2 (medium pollution) for As and Ni in Suburban area (SA), whereas Hg is enriched in Urban area (UA). Location map of the target area of the study. - COLLAPSE
    November 2019
  • Article

    Optimal Fertilizer Requirement for 9 Greenhouse Vegetable Crop Cultivation with Fertilization System: On-Site Survey
    Ye-Jin Lee, Seul-Bi Lee, and Jwakyung Sung
    The fertigation system has continuously been increasing to extend crop cultivation, to provide simultaneously water and mineral nutrients, and to finally enhance ... + READ MORE
    The fertigation system has continuously been increasing to extend crop cultivation, to provide simultaneously water and mineral nutrients, and to finally enhance yield and quality. The fertigation has a strength to regulate water and fertilizer relatively freely without any limitation of time, quantity, and type of fertilizers. However, a decision for those extremely depends on farmer’s experience due to an absence of standardized fertigation manual for each crop. As a measure to solve these problems, it should be firstly considered when, what and how farmers implement various requirements, and thus we surveyed some basic information to make a concept for crop-customized fertigation manual. The workflow was as followed: 1) choose crops → 9 major vegetables growing with fertigation, 2) monitor massive production area and select 2 sites with different cultivation period, 3) on-site survey and sampling at least two times during cultivation, early harvest and maximum harvest stages, and 4) analyze soil and plant samples and compute optimal rates for crop- and cultivation type-customized fertigation. Plant density was greater in forcing cultivation, and application rates were relatively higher in sequential harvest. The ratio of top dressing (fertigation) to total application generally ranged from 60 - 80% although some farmers were beyond the bounds. Mineral nutrient contents (N, P, and K) were more concentrated in Solanaceae, and it was observed that the quantity and concentration of fertigation were higher in sequential (e.g. cucumber) compared to once (e. g. watermelon). Given the result from the present on-site survey, it is carefully suggested to revise an application rate of top dressing for fertigation, to make the standardized- or customized-fertigation manual by crops, to implement practical means to optimize soil mineral contents, and to extend an education about application of smart and effective fertigation for farmers. Differences in nutrients uptake by cultivation period and crops under fertigation system. Species Crop Cultivation period Uptake (kg 10a-1) N P K Solanaceae Pepper Sep. ~ June 27.7 ± 5.9 3.7 ± 0.8 32.2 ± 5.0 Feb. ~ June 19.4 ± 3.3 2.5 ± 0.5 22.2 ± 3.5 Tomato Sep. ~ Apr. 12.0 ± 0.9 3.3 ± 0.3 25.5 ± 2.3 May ~ Oct. 21.3 ± 4.3 5.8 ± 1.0 41.1 ± 6.3 Eggplant Sep. ~ July 44.6 ± 5.2 9.4 ± 0.4 99.5 ± 9.0 Feb. ~ July 30.7 ± 10.9 5.8 ± 2.4 56.7 ± 14.5 Cucurbitaceae Cucumber Dec. ~ May 18.7 ± 1.5 4.0 ± 0.3 16.7 ± 1.2 Jan. ~ July 30.8 ± 2.4 6.6 ± 0.5 27.4 ± 2.1 Watermelon Jan. ~ Apr. 9.6 ± 1.0 1.4 ± 0.1 15.6 ± 1.6 Mar. ~ June 8.0 ± 1.3 1.2 ± 0.1 13.9 ± 1.5 Oriental melon Dec. ~ Aug. 10.6 ± 2.7 2.1 ± 0.5 19.0 ± 4.1 Melon Jan. ~ May 9.3 ± 1.3 2.5 ± 0.3 19.7 ± 2.9 Apr. ~ July 12.1 ± 4.5 3.2 ± 1.3 24.4 ± 8.2 Green pumpkin Mar. ~ July 24.9 ± 7.8 5.5 ± 1.7 30.3 ± 9.5 Rosaceae Strawberry Sep. ~ May 13.0 ± 2.8 2.8 ± 0.6 17.1 ± 3.6 - COLLAPSE
    November 2019
  • Article

    Soil Organic Carbon Fractions and Stocks as Affected by Organic Fertilizers in Rice Paddy Soil
    Hyun Young Hwang, Seong Heon Kim, Myeong Sook Kim, Dong Won Lee, Jae Eun Rim, Jae Hong Shim, and Seong Jin Park
    This research evaluated the effect of different organic fertilization (OF) on soil organic carbon (SOC) stock and fractions in rice paddy soil ... + READ MORE
    This research evaluated the effect of different organic fertilization (OF) on soil organic carbon (SOC) stock and fractions in rice paddy soil. The OF system consisted with NPK, NPK+Rice straw (NPK+RS), NPK+Cow compost (NPK+CC), NPK+Swine compost (NPK+SC) and no-fertilization (Control). Labile organic C fractions and humification rates were characterized and SOC stock was determined with bulk density and SOC content. Application of OF significantly SOC content by 7-12% and 23-33% over the NPK and control, while it decreased bulk density by 2-6% and 11-14%. The lowest bulk density was found in RS, which indicated the improvement of soil physical property. The highest SOC stock (38-39 kg C ha-1) was observed in SC and CC treatments. The SOC stock showed significant negative correlation with bulk density (p < 0.001), and positively correlated with humification rate, grain yield (p < 0.01) and HWEC and straw yield (p < 0.05), indicating key roles of SOC on soil quality. These results showed that the OF application largely increased SOC stocks, rice yield, and concentration of labile C and stable C. Therefore, application of OF is recommendable for suitable soil management strategy to improve soil fertility and increase crop yield in rice paddy field. Correlation analysis between soil organic carbon fractions under different fertilization system. Parameter SOC† Bulk density HA FA HA/FA§ HR¶ HA/SOM∮ FA/SOM∮ WEC∫ HWEC∫ Grain Straw SOC stock 1 B. density - < 0.001***† 1 HA 0.103 0.070 1 FA 0.013* 0.027* 0.008** 1 HA/FA 0.754 0.512 < 0.001*** 0.801 1 HR 0.008 - 0.010** < 0.001*** < 0.001*** 0.021* 1 HA/SOM 0.032* - 0.026* < 0.001*** 0.004** 0.001*** 0.001*** 1 FA/SOM 0.001*** - 0.007** 0.009** < 0.001*** 0.787 0.001*** 0.003** 1 WEC < 0.001 - 0.001*** 0.214 0.026* 0.986 0.035* 0.099 0.006** 1 HWEC 0.047* - 0.039* 0.431 0.045* 0.680 0.153 0.310 0.030* 0.07 1 Grain 0.011* - 0.004** 0.157 0.450 0.206 0.105 0.093 0.254 0.10 0.060 1 Straw 0.043* - 0.004** 0.433 0.857 0.360 0.356 0.315 0.586 0.039* 0.207 < 0.001*** 1 †*, **, and *** denote significance at the 5, 1, and 0.1% levels, respectively. †SOC: Soil organic carbon §HA/FA: Ratio of humic acid content and fulvic acid content ¶HR: Humification rate ∮HA/SOM and FA/SOM: Proportion of humic acid to SOM content and Proportion of fulvic acid to SOM content ∫WEC and HWEC: Water extractable carbon and hot water extractable carbon - COLLAPSE
    November 2019
  • Article

    Effects of Winter Cultivation of Green Manure Crop and Application of Organic Resources on Watermelon Yield and Soil Physico-chemical Properties in Greenhouse
    Young-Sang Kim, Gon-Sig Yun, Yu-Min Jeon, Eun-Jeong Kim, Sol-Ji Noh, Sung-Won Park, Tai-Il Kim, and Sung-Taek Hong
    Organic cultivation is the key to how to efficiently produce agricultural products by using organic resources produced in nature. Use of organic ... + READ MORE
    Organic cultivation is the key to how to efficiently produce agricultural products by using organic resources produced in nature. Use of organic resources enables stable production of agricultural products and is the basis of natural circulation farming methods by preserving agricultural environment. This study was conducted to develop organic watermelon cultivation technology by investigating the effect of winter cultivation of green manure crop and application of organic resources on the physico-chemical properties of soils for the production of organic watermelons. In the test, organic farms were used for cultivating green manure crop and non-cultivating green manure during winter break, and oil, mixed oil, poultry, and guano as organic resources. The growth characteristics of watermelon were higher in winter cultivation of green manure crop, such as stem diameter, leaf length, leaf width, and fresh weight than in the control (no crops). The fruit characteristics and yield of watermelon were significantly higher in winter cultivation of green manure crop than in the control, and the yield of watermelon was similar within organic resources. The soil chemistry have lower electrical conductivity (EC) and higher soil organic matter in winter cultivation of green manure crop and soil physical properties have lower bulk density and higher porosity in winter cultivation of green manure crop. These results showed that the cultivation of winter green crop in greenhouse and application of organic resources improved soil physicochemical properties and watermelon productivity. Effect of winter cultivation of green crop and application of organic resources on the watermelon productivity. Treatments (A) Organic Resources (B) Fruit weight Fruit width Fruit length Fruit thikness Sugar content Commodity rate Marketable Yield kg ea-1 ----------------- cm ----------------- °Brix % kg 10a-1 Non-Green manure crop Oil cake 9.0c† 25.9b 29.8b 1.0a 11.2b 90.2b 6,079c Mixed oil cake 9.3b 26.4ab 30.5ab 1.1a 11.4ab 90.7ab 6,294bc Poultry manure 9.3b 26.0b 30.2ab 1.1a 11.4ab 90.9ab 6,348bc Guano 9.4b 26.3ab 30.2a 1.1a 11.3ab 91.6a 6,439b Average 9.3 26.2 30.2 1.1 11.3 90.9 6,290 Green manure crop Oil cake 9.7ab 26.0b 31.6ab 1.1a 11.3b 90.2b 6,565b Mixed oil cake 10.0ab 26.5a 31.8a 1.1a 11.4ab 91.0a 6,814a Poultry manure 10.3a 26.9a 32.2a 1.1a 11.5a 90.8ab 6,942a Guano 10.4a 27.3a 31.4ab 1.1a 11.3ab 90.8ab 7,089a Average 10.1 26.7 31.8 1.1 11.4 90.7 6,853 Significance Two-way ANOVA A ** * * NS * * * B NS * * NS * * * A×B * NS NS NS NS NS NS †Mean separation within columns by Duncan's multiple range test at p = 0.05. NS, *, **Nonsignificant or significant at p ≤0.05 or 0.01, respectively. - COLLAPSE
    November 2019
  • Article

    Assessment of Heavy Metal Concentrations in the Arable Soils near Industrial Complexes in Gangwon, Chungnam, Jeonnam, and Gyeongnam Provinces of South Korea
    Tae-Gu Lee, Myung-Suk Kong, Eun-Jin Lee, Ha-il Jung, Yihyun Kim, Goo-Bok Jung, Jae-E Yang, Sung-Chul Kim, Gi-In Kim, Gwon-Rae Kim, and Mi-Jin Chae
    Heavy metal (HM) pollution in agricultural lands and waters, which is rapidly increasing due to social and industrial activities, such as mining ... + READ MORE
    Heavy metal (HM) pollution in agricultural lands and waters, which is rapidly increasing due to social and industrial activities, such as mining and smelting. Moreover, HM contamination causes serious environmental problems and adversely influences on the safety of agricultural production. This study established the concentrations of HM on the arable lands near industrial complexes in Gangwon (GW), Chungnam (CN), Jeonnam (JN), and Gyeongnam (GN) in South Korea. Soil samples were collected and established from 600 sites of agricultural lands nearby 60 industrial complexes in the selected provinces. Eight HMs (Cd, Cu, Pb, Zn, Ni, Cr, As and Zn) were analyzed to compare degrees of the HM pollution using standard analytical methods. The average total concentration of all HMs from samples of the analyzed soils did not exceed the warning criteria as suggested by the Soil Environmental Conservation Law of Korea. The concentration of Cd, Cu, Pb, Zn, Ni, As and Hg were mostly distributed below one half concentration of warning criteria, except for the Cr and Hg. Particularly, 99.2% of Hg concentrations among the assessed samples distributed below one-twentieth values of the warning criteria. Contamination degree (Cd) of GW and GN provinces were moderate degree, CN and JN province were low degree contamination. Four provinces were classified as “uncontaminated” by PI (Pollution index). Contamination assessment using Cf†, Cd† and PI§. Province Cf Cd PI Cu Pb Zn Ni As GW 1.2 2.8 1.6 1.1 2.2 9.0 0.23 CN 1.0 1.3 1.3 1.2 1.5 6.4 0.17 JN 0.6 2.6 0.8 0.6 1.4 5.9 0.14 GN 2.8 1.4 1.8 1.6 1.7 9.4 0.24 GW, Gangwon; CN, Cungnam; JN, Jeonnam; GN, Gyeongnam. †Cf, Contamination factor. †Cd, Contamination degree. §PI, Pollution index. - COLLAPSE
    November 2019
  • Article

    The Effect of Food Waste Compost on Chinese Cabbage Growth and Change of Soil Properties
    Jae Hong Yoo, Young Don Lee, and Jin Ho Joo
    The objective of this research is to evaluate the effect of food waste compost application on Chinese cabbage growth and soil chemical ... + READ MORE
    The objective of this research is to evaluate the effect of food waste compost application on Chinese cabbage growth and soil chemical properties. For field experiment, seven different treatments (livestock compost (LC), livestock compost + chemical fertilizer (NPK), food waste compost (FWC), food waste compost + chemical fertilizer, food waste compost + livestock compost (FWC+LC), food waste compost + livestock compost + chemical fertilizer, and control) were applied to Chinese cabbage grown field. All the treatment were carried out in 3 replicates with completely randomized design. Treatment of FWC+LC+NPK showed highest values in all parameters (leaf length, leaf width, chlorophyll contents, fresh and dry weight) of Chinese cabbage. Especially fresh and dry weight of Chinese cabbage treated with FWC+LC+NPK showed two times higher values compared to control. The electrical conductivity, organic matter, and cation exchange capacity in soils treated with both FWC and LC showed significant increase compared to control, while pH, and available P2O5 content did not. Chinese cabbage growth with different treatments of compost. Treatments Leaf length Leaf width Chlorophyll Fresh weight Dry weight -------------- cm -------------- O.D (SPAD) ----------------- g ----------------- Control 33.7±1.06e† 23.4±2.66e 44.1±1.13c 1122±376.89b 166.7±50.33d LC‡ 39.9±0.48cd 27.9±0.47cd 50.3±0.69bc 1760±177.76ab 234.3±30.55cd FWC 37.6±2.63d 25.8±1.22de 49.2±7.26bc 1598±264.28ab 213.3±5.77d FWC+LC 42.3±1.42bc 30.2±1.93bc 51.1±1.56abc 1893±608.28ab 246.7±11.55bcd LC+NPK 44.8±1.19ab 33.5±1.04ab 55.9±3.91ab 2148±135.81a 309.0±20.00ab FWC+NPK 43.7±1.38b 32.1±1.20b 53.7±2.70ab 1949±534.15ab 298.3±64.29abc FWC+LC+NPK 47.6±1.95a 36.3±1.32a 59.3±4.89a 2240±373.36a 347.7±23.09a †The different letters are significantly (p < 0.05) different according to Duncan's multiple test. ‡LC, Livestock compost; FWC, Food waste compost. - COLLAPSE
    November 2019
  • Article

    Effect of Optimum Nutrient Management on Productivity and Nitrogen Balance in Rice Cultivation: A Review
    Seul-Bi Lee, Yang-Min Kim, Ye-Jin Lee, Yo-Sung Song, Cheol-Hyun Ryu, Deog-Bae Lee, Chan-Wook Lee, Chang-Hoon Lee, and Jwakyung Sung
    Given continuous needs for a public duty of agriculture and rural area, an effort to improve nutrient management in agricultural sector is ... + READ MORE
    Given continuous needs for a public duty of agriculture and rural area, an effort to improve nutrient management in agricultural sector is strongly required. As a measure to solve these problems, Korean government (MAFRA) introduced the promotion policy called as “Agro-Environment Conservation Program (AECP)” in 2018 and has expanded 5 projet sites in 2019 from 3 in 2018. The program has a variety of agricultural activity to conserve soil, water, air, ecology and landscape. Of those, the nutrient input activity which is one of sub-activities is closely involved in not only crop productivity but also water quality and air pollution. Therefore, in order to lead a soft landing of AECP, it is essential to evaluate the conservation effects in a scientific point of view. In this respect, we focused on evaluating the effect of recommended nutrient input activities, standard fertilization and soil test fertilization, on rice productivity and nitrogen balance. The effect of nutrient management which is explained by rice yield and nitrogen balance was estimated with the combination of soil characteristics and rice varieties. Rice yield by recommended fertilization was 654 kg per 10a, 6% lower than control, but there was no statistical significance. By contrast, nitrogen balance was 4.7 kg lower, which means great improvement, in the recommended than the control. Conclusively, the recommended fertilization like soil test fertilization is expected to be useful as a measure to reduce nutrient balance, to ensure crop productivity, and finally to perform a public role of agriculture. Effect of optimum fertilization on rice productivity and nitrogen balance with rice cultivation (STF: Soil test (or Standard) fertilization, CF: Conventional Fertilization (or Maximum fertilization)) analyzed from literatures. - COLLAPSE
    November 2019
  • Article

    Nutrient Characteristics and Redox Potential Changes as Affected by Water Management in Rice Paddy Weighing Lysimeter
    Myung-Suk Kong, Tae-Gu Lee, Seong-Soo Kang, Eun-Jin Lee, Goo-Bok Jung, Yoo-Hak Kim, and Ha-il Jung
    This study was designed to assess the nutrients characteristics and redox potential changes as affected by water management condition in rice paddy ... + READ MORE
    This study was designed to assess the nutrients characteristics and redox potential changes as affected by water management condition in rice paddy weighing lysimeter. Rice was grown from June to October 2015, and the water management was consisted of two methods: continuously flooding (CF) and alternate wetting and drying (AWD). Under the CF condition, the redox potential (Eh) of 5 cm topsoil began to decrease rapidly and maintained around -260 to -200 mV. The AWD showed the oxidation condition. The changes of soil pH in CF and AWD ranged from 6.0 to 7.0 and 5.7 to 7.1, respectively. Soil pH in the AWD condition indicated up and down patterns by irrigation. In changes in nutrient contents of the soil solutions, nitrate nitrogen (NO3-N) was initially 12.2 to 26.6 mg L-1 at the highest concentration, and the concentration of ammonia nitrogen (NH4-N) and phosphate (PO43-) appeared to be lower than 1 mg L-1 during rice cultivation. The grain yield of rice was significantly higher in the CF than in the AWD. Nitrogen and magnesium content in both rice grain and straw were not significantly different between the water management conditions. Phosphorous, potassium, and calcium content in the rice grain were not statistically different between CF and AWD conditions. However, the nutrient contents in rice straw were higher in the CF, compared with that in the AWD. Although the iron content in rice straw was higher in the CF than in the AWD, the manganese content showed an opposite tendency. Interestingly, soil maximum temperature at the daytime was significantly higher in the AWD than in the CF, whereas the soil minimum temperature at the night time was 0.5-0.9℃ lower in the AWD, compared with that of the CF. Therefore, these results suggest that the decrease in rice yield in AWD condition can be linked to the inhibition of phosphate absorption into rice plants under oxidized-soil condition and/or high temperature difference between day and night in the soil. Changes in the redox potential (Eh) of (A) 5, (B) 10, and (C) 15 cm soil depth under water management conditions of the continuously flooding (CF) and alternate wetting and drying (AWD). - COLLAPSE
    November 2019
  • Article

    Monitoring of Veterinary Antibiotics in the Agro-Environment
    Sung Chul Kim, Jin Wook Kim, Young Kyu Hong, Won il Kim, and Oh Kyung Kwon
    Antibiotics has been recognized as an emerging contaminant in the agro-environment such as soil, irrigation water, and plant because of antibiotic resistance ... + READ MORE
    Antibiotics has been recognized as an emerging contaminant in the agro-environment such as soil, irrigation water, and plant because of antibiotic resistance gene production. However, information about residual of antibiotics in the agro-environment is limited. Thus, antibiotic concentration in soil and cultivated plant was monitored in the two different region. Total of 7 different location was selected for soil and plant sampling and 6 antibiotics classified with tetracyclines (TCs) and sulfonamides (SAs) were analyzed. Result showed that all TCs and SAs were detected at least 2 locations while SMZ (sulfamethazine) and SMX (sulfamethoxazole) were not dected in the plant sample. Concentration range of TC and SA in the soil was 0.58 - 3.34, 0.12 - 3.02 µg kg-1 respectively. In case of plant, residual concentration was ranged 15.1 - 194.0, 24.9 - 36.3 µg kg-1. Depending on antibiotic properties and physicochemical properties of soil, residual amount of antibiotics in soil and plant was varied. Overall, antibiotics could be detected in the agri-environment and best management practice should be conducted for minimizing adverse effect of antibiotics on ecosystem and human health. Antibiotics in soil and bioaccumulation through plant uptake. - COLLAPSE
    November 2019