• Short Communication

    Results of Soil Survey for Environmental-friendly Agricultural Regions in 2018
    Sungang Yun, Byungkeun Hyun, Sangho Jeon, Woori Go, and Yeonkyu Sonn
    For the improvement and conservation of sustainable environmental-friendly agriculture, governmental project for base establishment of environmental-friendly agriculture, has been done since 1999 ... + READ MORE
    For the improvement and conservation of sustainable environmental-friendly agriculture, governmental project for base establishment of environmental-friendly agriculture, has been done since 1999 by the ministry of agriculture, food, and rural affairs. In relation with the project, investigation on fundamental soil survey on the 16 regions of environmental-friendly agricultural area selected as project implementation area was carried out in 2018. Some of results are as follow. Distribution of soil series was identified as 96 series among 405 series in nation wide. The highest population of soil series was Jisan series occupying 10.7% of that total investigated area. The number of soil series occupying over 300 field in each soil series were 8 and the related area was 53.5% among total investigated region. Land use recommendation were paddy as 83.7% and upland as 12.9% of total agricultural area, however land use type, investigated in base of application papers were various as paddy, upland, horticulture, and orchard. Distribution of soil family were in the order of fine loamy as 39.6%, coarse loamy as 31.2%. Land slope were mostly plain (slope 0-2%) and slight slope (slope 2-7%), those occupied 82.6% of total investigated area. Distribution of drainage class of very poorly, poorly, somewhat poorly, moderately well, well and somewhat excessively was 95.9% among total investigated area. - COLLAPSE
    May 2019
  • Article

    Effect of Large-Scale Cultivation of Bacillus amlyoliquefaciens Y1 Using Fertilizer Based Medium for Control of Citrus Melanose Causing Diaporthe citri
    Dong-Ryul Lee, Chaw Ei Htwe Maung, Ajuna Henry, and Kil-Yong Kim
    The melanose disease causing Diaporthe citri is important pathogen in citrus plants worldwide. Currently, there are few researches related to biological control ... + READ MORE
    The melanose disease causing Diaporthe citri is important pathogen in citrus plants worldwide. Currently, there are few researches related to biological control of melanose disease. In this study, we investigated control of Diaporthe citri by Bacillus amyloliquefaciens Y1 isolated from the soil. Low-cost fertilizer based PB medium and large-scale fermenter have been developed for field application of biological control. We prove that Y1 can be successfully grown in large-scale fermenters using PB medium without contamination. In addition, Y1 bacterial culture filtrates (BCF) of large-scale cultivation in PB medium (LP-Y1), present better growth inhibition of D. citri than small-scale cultivation in TSB medium (ST-Y1). Microscopic observations also showed that pathogen mycelial morphology was significantly affected by BCF, presumably due to metabolites produced by Y1. Finally, in pot experiment, pre-treatment with fungicide and Y1 to leaves significantly reduced disease incidence compared to the control group. This study showed that Y1 incubated with fertilizer based medium inhibited the occurrence of D. citri and could be grown in large scale field conditions without contamination as well as cost optimization. - COLLAPSE
    May 2019
  • Article

    Reclassification of Korean Soils According to Revised Soil Taxonomy
    Kwan-Cheol Song, Byung-Keun Hyun, and Ho-Jun Kang
    Korean soils are classified officially by Soil Taxonomy. Soils in Korea were classified into 7 orders, 14 suborders, 27 great groups, and ... + READ MORE
    Korean soils are classified officially by Soil Taxonomy. Soils in Korea were classified into 7 orders, 14 suborders, 27 great groups, and 390 soil series. The dominant soils in Korea were Inceptisols and Entisols, and Alfisols, Ultisols, Andisols, Mollisols, and Histosols were distributed to a small extent. This study was conducted to reclassify Korean soils based on the second edition of Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys. Morphological properties of typifying pedons of 405 soils were investigated and physio-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual of USDA. Alfisols of 44 soils were reclassified; 16 soils were reclassified as Ultisols and 3 soils as Mollisols. Forty Andisols were reclassified; 3 soils were reclassified as other orders. Sixty-four Entisols soils were reclassified; 11 soils were reclassified as Inceptisols, 4 soils as Mollisols, and 3 soils as Andisols. Two hundreds and ten Inceptisols soils were reclassified; 39 soils were reclassified as Alfisols, 21 soils as Ultisols, 13 soils as Mollisols, and 2 soils as Andisols. Twenty-one Inceptisols soils, 16 Alfisols soils, and one Andisols soil were reclassified as Ultisols. As a result of reclassification of Korean soils, Korean soils are now classified into 7 orders, 17 suborders, 39 great groups, 85 subgroups, and 405 soil series. Alfisols and Ultisols are increased remarkably. Sixty Inceptisols soils are reclassified as Alfisols or Ultisols; 44 soils including 30 paddy soils are distributed on fluvio-marine plains, alluvial plaines, local valleys, alluvial fans, and mountain foot slopes. Soils distributed on rolling to hilly areas are mainly developed as Ultisols and some are as Alfisols. Also soils distributed on diluvial terrace are mainly developed as Ultisols and some are as Alfisols. Only two Mollisols soils were developed to a small extent. But 15 soils in Jeju Island and Ulreung Island, 3 soils in limestone areas, and 5 soils in coastal areas are classified as Mollisols. Inceptisols occupied 76.6% and Entisols occupied 12.9% of the whole country. Ultisols and Alfisols occupied only 5.0% and 3.8% respectively. Many soils deveped on rolling to hilly, diluvial terraces, local valleys, mountain foot slopes, etc. are reclassified as Ultisols and Alfisols. As a result Ultisols occupy 12.9% and Alfisols occupy 8.8% of the whole country. - COLLAPSE
    May 2019
  • Article

    Revised Soil Survey of Gimpo City in Gyeonggido
    Byung-Keun Hyun, Yeon-Kyu Sonn, Sang-Ho Jeon, Soon-Gang Yun, Woo-Ri Goh, Sug-Jae Jung, and Jung-Won Choi
    Agricultural lands have decreased continuously because of urbanization, land consolidation, road construction, etc. Especially, rapid urbanizing areas such as Gimpo-city in South ... + READ MORE
    Agricultural lands have decreased continuously because of urbanization, land consolidation, road construction, etc. Especially, rapid urbanizing areas such as Gimpo-city in South Korea has the severe land-use change. In this regard, aim of our study was to investigate land-use changes including soil properties and soil information to provide the basic soil information and soil management practices in the region. The arable land in Gimpo-city had been reduced by 47,121 ha in 2017 since 1999. The ratio of the reduced arable land was about 22.1%. Our results showed that paddy fields located in alluvial plains were changed into upland or green house. In particular, paddy fields have been changed to not only upland, orchard, greenhouse cultivation but also fallow land. Moreover, our research using 462 soil codes (soil phases) and 1207.3 ha indicated that the number of soil series and soil phase increased to 47 and 79 from 43 and 74 individually. The largest increased area was Mangyeong (coarse silty, mixed, mesic family of Fluvaquentic Endoaquepts) soil series 418.3 ha which were modified from the existing Jeongbug and Chunpo soil series. - COLLAPSE
    May 2019
  • Article

    Soil Quality Assessment Based on Different Properties of Remediated Soil Affected by Various Organic Amendments
    Dong-Jin Kim, Byung-Koo Ahn, and Jin-Ho Lee
    Remediated soil can be one of valuable resources for sustainable agriculture after improving its quality and properties with proper treatments. Therefore, this ... + READ MORE
    Remediated soil can be one of valuable resources for sustainable agriculture after improving its quality and properties with proper treatments. Therefore, this study was conducted to estimate changes in soil properties and soil quality for improving remediated soil contaminated with petroleum as affected by the applications of various organic amendments as soil conditioners including biochar (BC), charcoal (CC), and livestock manure compost (LC). Two remediated soils, remediated soil A and B (RSA and RSB) that previously contaminated with different concentrations of total petroleum hydrocarbons, were alkaline soils with up to 8.5 of soil pH, very low soil organic matter (SOM) contents and available phosphate (available P2O5) concentrations, and very high exchangeable Ca concentrations. Thus, these soils had very unfavorable conditions for crop growth. RSA and RSB were treated with BC, CC, and LC in levels of 0.0%, 1.0%, and 5.0% on dry weight bases. The remediated soils treated with organic soil conditioners were incubated for 2, 4, 8 and 16 weeks at room temperature (24 ± 2°C). SOM contents increased with all the treatments. In particular, SOM in RSB increased up to 19.5 g kg-1 with BC 5.0% treatment (BC5, 16-week), which was 2 times higher than that in both RSA and RSB soils without BC applications (Control soils). Also, available P2O5 concentrations increased to 24.9 mg kg-1 (RSA, 16-week), and 17.0 mg kg-1 (RSB, 8-week) with BC5. However, available P2O5 concentration in the remediated soils was very lower than that of the optimal value for cultivating crops suggested by National Institute of Agricultural Sciences in the Republic of Korea. Available P2O5 was negatively correlated with soil pH (p < 0.01) and exchangeable Ca (p < 0.01). Soil quality index (SQI) and weight additive soil quality index (SQIW) were positively correlated with SOM (p < 0.01). The mean value of soil quality indices were 39.3, 56.0, 40.0, and 54.5 for RSA Control, RSA BC5, RSB Control, and RSB BC5, respectively. The highest soil quality index was found in the remediated soil with BC treatment. The remediated soils require the immediate solution for the poor soil quality, and thus should need methodical and continuous management. - COLLAPSE
    May 2019
  • Article

    Effect of Subsoil Breaking on Improvement of Soil Physical Properties in Agricultural Land
    Yong-Seon Zhang, Dong-Jin Kim, Kang-Ho Jung, Hee-Rae Cho, Kyung-Hwa Han, and Hyub-Sung Lee
    When the hardpan is formed in the soil, crop productivity reduces due to inhibition of crop root growth, water permeability, and capillary ... + READ MORE
    When the hardpan is formed in the soil, crop productivity reduces due to inhibition of crop root growth, water permeability, and capillary rise, for that reason, improvement of soil physical properties is needed. Therefore, this study investigated the soil physical properties after application of various subsoil breaking method to agricultural lands to establish the effect of improving soil physical properties by subsoil breaking. The penetration resistance of the soils treated with spading (in Wanju), aeration (in Sancheong), and deep plowing (in Namwon) was lower than that of the control soil treated with conventional plowing. However, the penetration resistance of the soils treated with excavation (in Andong) and towing (in Chungju) was higher than that of the control soil. The effect of improving the soil physical properties such as increasing effective soil depth, decreasing bulk density, and increasing permeability observed in the soil subjected to spading, aeration, and deep plowing. Although, in soil treated with excavation and towing methods, it was found that the physical properties such as increasing bulk density and decreasing permeability were deteriorated due to re-compaction such as the formation of a platy structure on the topsoil by using unsuitable agricultural machinery after subsoil breaking. Therefore, the subsoil breaking cycle should be decided depending on the presence or absence of the soil hardpan in consideration of soil management histories, such as the soil moisture condition and the type and use period of agricultural machinery after subsoil breaking. - COLLAPSE
    May 2019
  • Article

    Estimating Soil Properties and Rice Plant Growth in Liquefaction Paddy Land as Affected by Earthquake in Pohang City of Korea
    Yong-Seon Zhang, Dong-Jin Kim, Jun-Hong Park, Se-Yeong Choi, Myung-Sook Kim, and Hyub-Sung Lee
    On 15th November 2017, an earthquake (magnitude 5.5) occurred at 36.10N and 129.37E on Pohang city in Korea. Due ... + READ MORE
    On 15th November 2017, an earthquake (magnitude 5.5) occurred at 36.10N and 129.37E on Pohang city in Korea. Due to the earthquake, liquefaction occurred in some agricultural lands of Yongcheon-ri, Heunghae-eup, Buk-gu, Pohang-si, Korea. This study investigated the physical and chemical properties of soil and liquefied sand and crop growth in the liquefaction site as affected by earthquake. The scale of liquefaction site in the experimental paddy was 30 - 50 cm ellipse, and most of the sand mixed with 14 - 22% of the gravel was piled up. The liquefaction scale was less than 0.01% of the area in each paddy land. The pH of the liquefied sand was a suitable property for rice cultivation, and heavy metal contents were lower than the concern level of soil environmental conservation act. As a result of comparing the liquefaction point (LP) and the around point 30 cm (AP) away from the LP, the partial cracked line was verified in the profile of LP. However, the soil structure maintained with the soil penetration resistance of 3 MPa or more. As the scale of sand liquefaction was small and the soil structure maintained, it considered that there was no problem in water and nutrient movement of soil and farming work. The effects of liquefaction on the growth and yield of rice were estimated to be insignificant because there was no statistically significant difference in plant height, stem height, panicle length, panicle number per fill, grain-filling rate, and yield of rice plants in the liquefaction site and control site. - COLLAPSE
    May 2019
  • Article

    Occurrence of Veterinary Antibiotics in the Groundwater of Arable Land
    Young Kyu Hong, Won Suk Choi, Hye Ji Kim, Seung Yun Lee, and Sung Chul Kim
    Groundwater pollution has been concerned in the agricultural area due to release of fertilizer, pesticide, and veterinary antibiotics (VAs). Especially, emerging contaminants ... + READ MORE
    Groundwater pollution has been concerned in the agricultural area due to release of fertilizer, pesticide, and veterinary antibiotics (VAs). Especially, emerging contaminants such as VAs can cause adverse effect not only on ecosystem but also on human health. Main objective of this research was to examine groundwater near at the animal feeding operation for evaluating occurrence of VAs. Groundwater sample was collected from five different province and three sulfonamides antibiotics (sulfamethazine: SMZ, sulfathiazole: STZ, sulfamethoxazole: SMX) were measured. Extraction of antibiotics was conducted with solid phase extraction and HPLC/MS/MS was used for quantification. Recovery of three antibiotics was ranged 88-126% and R2 value of external calibration curve was 0.99 for all three compounds. Among 3 VAs, only SMZ was detected at the range of 26.6-40.0 ng L-1. Comparing SMZ concentration between control (no animal feeding operation within 2 km radius) and sampling points (animal feeding operation within 0.5 km radius), no difference was observed. This result might indicated that occurrence of VAs in the groundwater can be originated from compost spread in the agricultural field and released into groundwater after rainfall as a nonpoint source. However, more detailed analysis is required for better understanding of VAs occurrence in the groundwater. - COLLAPSE
    May 2019
  • Article

    Tillage Effects on Evapotranspiration of Three Different Paddy Soils in Spring Season as Tested by Monolithic Weighable Lysimeters
    Kyungwha Han and Mijin Seo
    This study was conducted to evaluate the effect of tillage in spring season before rice cultivation on evapotranspiration (ET) of three different ... + READ MORE
    This study was conducted to evaluate the effect of tillage in spring season before rice cultivation on evapotranspiration (ET) of three different paddy soils. Precision weighing lysimeters, filled with three undisturbed paddy soils, were used, and each texture was silty clay loam, loam, and sandy loam. For tillage treatments, the hand tillage (HT) was conducted to a depth of 8 cm by using a spatula with a 5 cm width on Mar. 8, 2016. The no-tillage (NT) treatments were continuously kept as no-tillage conditions during the study period. In 2016 spring of this experimental field, two contrary periods in weather condition, dry period from Mar. 8 to Apr. 5 and rainy period from Apr. 6 to Apr. 30, were used to analyze the effects of tillage on soil water status and evapotranspiration in paddy soils. In dry period with rare rainfall, HT treatment had lower evapotranspiration loss than NT treatment except sandy loam soil. Especially, the soil water tension difference over the dry period between HT and NT was highest in silty clay loam soils, probably due to transection of crack by tillage. On the other hand, the significant tillage effect on ET reduction in all soils over total period, dry and rainy periods, was not observed with high flucturation of weed biomass. This is probably not only because frequent rainfall events in rainy period could cause the reconnection of capillaries through water dispersion of clods, but also because nutrient mineralization at rewetting after surface tillage could promote ET through better weed growth. Nevertheless, in drought condition, tillage operation in early spring could be useful to decease water loss by evapotranspiration. - COLLAPSE
    May 2019