• Short Communication

    Development of Soil Organic Carbon Reference for Advancing National Greenhouse Gas Inventory
    Seong-Jin Park*, Chang-Hoon Lee, Myung-Sook Kim, and Seok-Cheol Kim
    Soil Organic Carbon (SOC) plays an important role in the global carbon cycle and climate change. The carbon stored in soil is ... + READ MORE
    Soil Organic Carbon (SOC) plays an important role in the global carbon cycle and climate change. The carbon stored in soil is estimated to be 2-3 times of the atmosphere’s carbon. In this study, we estimated SOC storage at national scale and generated country specific factor related Soil Organic Carbon reference (SOCref) alternative IPCC’s default value. The soil data was collected about 5,052 pedons and 21,170 layers by Korean Rural Development Adminstration (RDA) from 1970 to 1999. Because of lacking of bulk density (BD), we generated BD using Adam’s equation (1999) and used to equal-area smoothing spline depth function for calculating carbon density. The analytical results showed that the total amount of soil organic carbon in South Korea was about 395 megaton, and that the average carbon density was about 45.7 ton C ha-1. The average and confidence interval of carbon density according to IPCC classification‘s 4 categories ; Sandy, Low Activity Clay (LAC), High Activity Clay (HAC), and Volcanic soil type were 19.7±4.5 Mg C ha-1, 37.6±2.1, 39.1±16.2, and 127.8±16.4 respectively. We also compared the SOCref to 2006 IPCC Guideline’s default value. The results showed SOCref of Sandy, LAC soil type and HAC was lower, and Volcanic soil type was higher than IPCC’s default value. This study presents basic data and an analysis method for carbon stock and storage study and also provides scientific support for policy making efforts to control CO2 emission in South Korea. - COLLAPSE
    November 2018
  • Article

    Spatial Changes and Land Use of Arable Land in China
    Kyo Suk Lee, Dong Sung Lee1, Se Won Min, Sung Chul Kim, Il-Hwan Seo, and Doug Young Chung*
    Numerous concerns have been raised in China over the issues of limited arable land resources and food security in China. Especially, the ... + READ MORE
    Numerous concerns have been raised in China over the issues of limited arable land resources and food security in China. Especially, the record levels of soil pollution and the conversion of the arable land become the serious threat to the nation’s capacity to produce adequate levels of staple cereal crops for Chinese people. Most of arable land, only 15% of the country, mainly concentrated on the central eastern coast and along the Yangtze and Yellow river valleys which had the highest sediment deposit among the lands in China. An agricultural land in China was classified into four categories including arable land. The survey of spatial distribution and types of land use by in China established by remote sensing data and conventional aerial photography showed main land use features and the spatial pattern and processes of land use change for 15 regions covering China. The agricultural land area in 2015 was increased by 64.9% from that in 1960 while the changes of the arable land area ranged from decrease of 6.6% in 1980 to increase of 20.2% in 1990. Conclusively, we assume that Chinese government may have to figure out the practically adequate arable land area to produce safe food for people in China, bearing in mind of 135 million ha that is a minimum threshold to ensure adequate food production. - COLLAPSE
    November 2018
  • Article

    Water Use Efficiency of Soybean, Sorghum, Sesame with Different Groundwater Levels Using Lysimeter
    Dong Hyun Kim, Jin Young Choi, Soon Hong Kwon, Jung Duck So, Soon Goo Kwon, Ki Yeol Chung, Sang Hun Lee, and Jong Soon Kim*
    In South Korea, the area of agricultural land has steadily decreased and the overall food self-sufficiency rates have consistently dropped with a ... + READ MORE
    In South Korea, the area of agricultural land has steadily decreased and the overall food self-sufficiency rates have consistently dropped with a decrease in farm population since 2000. This study aimed to evaluate water requirements of crops soybean, sorghum, and sesame using lysimeter. Using the lysimeter with different groundwater levels, 20 cm and 40 cm, and different types of soils, sandy loam and clay loam, the evapotranspiration for crops was measured to determine the water requirement and the water use efficiency. The results showed that the maximum evapotranspiration of soybean and sesame was at the blooming stage, and that of sorghum was at the panicle formation stage. In water use efficiency, the optimal soil texture (groundwater level) for soybean was clay loam (40 cm), for sorghum was sandy loam (20 cm), and for sesame was sandy loam (40 cm). The water requirement of soybean and sesame was lowest at sandy loam (40 cm), while sorghum had the lowest at sandy loam (20 cm). The 100-kernel weight of soybean was found to be higher under the groundwater level 40 cm than 20 cm regardless of soil types, and 1,000-kernel weight of sorghum and sesame was found to be the highest under the sandy loam (40 cm). In consideration of these results, sandy loam (40 cm) was more suitable for cultivating soybean and sesame, and so was sandy loam (20 cm) for sorghum. The results of this study are expected to provide useful data for the development of an irrigation system which is possible to set the groundwater level as desired. - COLLAPSE
    November 2018
  • Short Communication

    Impact of Water Management on Arsenic and Cadmium Accumulation in Rice Grown Nearby Abandoned Mines in Korea
    Ji-Young Kim, Anitha Kunhikrishnan, Hyuck-Soo Kim, Da-Young Kim, Byeong-Chul Moon, Jeong-Gyu Kim, and Won-Il Kim*
    Managing arsenic (As) and cadmium (Cd) together in rice (Oryza sativa L.) plants is challenging and different strategies are being developed for ... + READ MORE
    Managing arsenic (As) and cadmium (Cd) together in rice (Oryza sativa L.) plants is challenging and different strategies are being developed for mitigating As and Cd loading into the rice grains. This study investigated the effect of water management on As and Cd accumulation in brown rice. A field plot experiment was conducted with five water management regimes [Flooded control, alternate wetting drying (AWD–60 and 40), and row (R-60 and R-40)] using two rice cultivars (Dasan and Boramchan). All the four treatments significantly reduced the concentration of As in brown rice compared to the flooded control, with R-40 treatment showing the least concentration. AWD and row treatments reduced As levels by 45-60% and by 32-55% in Dasan and Boramchan cultivars, respectively. However, increased Cd concentrations were noticed in both row and AWD treatments. The Dasan rice cultivar under the AWD-60 treatment reduced As without greatly increasing Cd concentration in brown rice, while also maintaining a competitive grain yield. The grain yields of both cultivars were influenced by different water regimes. While the flooded control showed the highest grain yield, between the cultivars, Boramchan showed an increase in grain yield under AWD-40 and R-40 treatments, and Dasan cultivar displayed higher grain yield in AWD-60 and R-60 treatments. AWD water management may be a promising strategy to reduce both As and Cd accumulation in rice grains, however, it depends on the selection of rice cultivars. - COLLAPSE
    November 2018
  • Short Communication

    Assessment of Hyperspectral Reflectance on Rice Leaf Inoculated with Bacterial Leaf Blight for Applicability of UAV Monitoring
    Kyung­Do Lee, Sang-Min Kim, Chan-Won Park, Kyu-Ho So, Ho-yong An, and Sang­Il Na*
    We analyzed the spectral reflectance characteristics of rice leaves according to the occurrence of bacterial leaf blight and the correlation between vegetation ... + READ MORE
    We analyzed the spectral reflectance characteristics of rice leaves according to the occurrence of bacterial leaf blight and the correlation between vegetation index and disease area ratio in order to evaluate the possibility of using Unmanned Aerial Vehicle (UAV) image for disease investigation. As a result, relationship between the spectral reflectance of inoculated rice leaves and the ratio of disease area showed a high correlation of 0.9 or more in wavelength from 700 nm to 750 nm. Also, the reflectance of the visible light region from 500 nm to 700 nm and the near infrared region in more than 800 nm showed a correlation from 0.8 to 0.9 more. The area ration of rice leaves increase rapidly after 10 days of inoculation. The vegetation index(NDVI, GNDVI and NDRE) that can be calculated by UAV images showed a tendency to decrease remarkably with increase of diseased area ratio. Relationship between the vegetation index and disease area ratio on the 10th day after the inoculation, in which disease area ratio increased rapidly, showed a negative linear correlation from -0.77 to -0.95. Therefore, it is considered that it is possible to analyze the diseased area by UAV image. - COLLAPSE
    November 2018
  • Article

    Effect of Barley and Hairy Vetch as Green Manures on Soil Nitrogen and Corn Productivity
    Sung Un Kim†, Eun Sang Jung†, Hyun Ho Lee, Jang Seong Ho, and Chang Oh Hong*
    The utilization of green manures as alternatives to reduce the use of chemical fertilizers is considered a good agricultural practice. So far, ... + READ MORE
    The utilization of green manures as alternatives to reduce the use of chemical fertilizers is considered a good agricultural practice. So far, many studies on determining effect of incorporation of green manure to paddy soil on change of rice productivity have been conducted in South Korea. However, there have been few studies on examining soil nitrogen (N) and corn productivity in upland soil incorporated with green manure. The objective of this study was to determine effect of single or mixture incorporation of green manures (hairy vetch and barley) to an upland soil on changes of inorganic N in soil and grain yield of corn plant. Single barley (B), single hairy vetch (HV), and mixture of barley and hairy vetch (B+HV) were sown on 2nd November in 2013 and incorporated to an upland soil on 12th May in 2014. Corn plant was sown on 12th May in 2014 and harvested on 25th August in 2014. Above ground, below ground, and total biomass yields of HV were significantly lower than those of B and B+HV. Even though N concentration in HV was the highest among the treatments, total N input amounts to the soil were not significantly different among the treatments due to the lowest biomass yield of HV. Also, there was no significant difference among the treatments in NH4+ and NO3- concentration in soil at corn harvest time. For those reason, there was no significant difference among the treatments in grain yield and N uptake of corn plant at harvest time. Based on the above results, single or mixture of B and HV did not affect changes of soil inorganic N and corn productivity in upland soil. - COLLAPSE
    November 2018
  • Article

    Decomposition of Pine and Oak Litters as Affected by Their Lignin and Mineral Concentrations
    Hyun-Jin Park†, Yong-Se Park†, Sang-Mo Lee, and Woo-Jung Choi*
    Tree litter chemistry such as lignin, nitrogen (N), calcium (Ca), phosphorus (P) and manganese (Mn) affects litter decomposition and ultimately alters the ... + READ MORE
    Tree litter chemistry such as lignin, nitrogen (N), calcium (Ca), phosphorus (P) and manganese (Mn) affects litter decomposition and ultimately alters the soil carbon (C) and nutrient dynamics. Specifically, it is well known that the ratio of lignin to N (lignin/N) is a key factor affecting litter decomposition; i.e., litter with low lignin and high N concentrations decomposes fast as compared to litter with high lignin and low N. However, no comprehensive study on the effects of various chemistry as well as lignin/N on the litter decomposition is available. To fill the research gap, this study investigated the variations in the decomposition of pine and oak litters with different chemistry. Split plot design with tree species as a main plot (pine and oak) and litter chemistry (e.g., low vs. high lignin/N) as a sub-plot were laid out in triplicates. Litter samples (1.5 g on the dry basis) were mixed with soils (30 g) and incubated for 45 days, and CO2 emission was monitored periodically. Litter addition increased the cumulative CO2 emissions (Ccum) by 16 times over the control soil without litter regardless of litter species and chemistry. The litters applied to the soil were decomposed by more than 20% of the initial during the incubation period. Regardless of species, the Ccum was higher for litter with high lignin/N than with low lignin/N in contradiction to the previous studies. These results suggest that CO2 emissions from litter decomposition may not be explained solely by the lignin/N of litters but should be deciphered by considering mineral concentration as well as lignin/N. Comparing two pine litter with different chemistry, decomposability of pine litter with high Ca and Mn concentration was greater than the other one due to the role of essential co-factor of Ca and Mn in ligninolytic enzyme. However, for two oak litter with different chemistry, P rather than Ca and Mn found to contribute to litter decomposition. Therefore, this study highlights the necessity of comprehensive understanding of the effects of various chemistry as well as lignin/N of litter on the decomposition of litter. - COLLAPSE
    November 2018
  • Article

    Establishment of Basic Carbon Unit and LCI DB on Compound Fertilizers in Korea
    Jong-Sik Lee*, Gun-Yeob Kim, Hyun-Cheol Jeong, Eun-Jung Choi, Sun-Il Lee, and Jin-Ho Huh
    To cope with climate change, all industry fields including agriculture endeavor to reduce carbon emissions. For calculating the amounts of carbon emission ... + READ MORE
    To cope with climate change, all industry fields including agriculture endeavor to reduce carbon emissions. For calculating the amounts of carbon emission on agricultural products, establishment of LCI DB (Life Cycle Inventory DataBase) on agro-materials are needed. At this study, LCI DB on several compound fertilizers were established to supply basic informations for conducting sustainable agriculture. Average basic carbon unit for compound fertilizers was 0.86 kg CO2-eq kgfertilizer-1, which ranged from 0.801 to 1.02 kg CO2-eq kgfertilizer-1. With type of fertilizer, 21-17-17, 17-21-17 and 15-15-15 appeared similar value, but the rest showed about 20% higher values. As the result of life cycle impact assessment on fertilizer(17-21-17), the value of GWP (Global Warming Potential), MAETP (Marine Aquatic Eco Toxicity Potential) and HTP (Human Toxicity Potential) were 0.801 kg CO2-eq kg-1, 0.458 and 0.424 kg 1,4 dichlorobenzene(DCB)-eq kg-1, respectively. Basic carbon unit would be used to calculate the amounts of carbon emitted for production process of agricultural products. Also, environmental impact assessment could be served for improving the weakness in fertilizer industry through clear up the vulnerable factors. - COLLAPSE
    November 2018
  • Short Communication

    Ammonia Volatilization in Acidic Mine Soils Applied with Livestock Manure Compost and Liming Materials
    Yong-Se Park, Hui-Seon Kim, Sang-Mo Lee, and Seok-In Yun*
    To investigate the possibility of ammonia volatilization in mine lands limed, we conducted an incubation experiment with treating livestock manure compost as ... + READ MORE
    To investigate the possibility of ammonia volatilization in mine lands limed, we conducted an incubation experiment with treating livestock manure compost as an organic fertilizer and dolomite and oyster shell as a liming material. For trapping ammonia volatilized, installing boric acid in a closed system was efficient, with a recovery of 101.2±3.7%. Treating compost and liming material increased soil pH to a range of 5.75-5.88 for a metal-mine soil and 6.02-6.06 for a coal-mine soil. Ammonium-N in soils decreased rapidly with time during early stage of incubation, but nitrate-N changed little. Accumulated ammonia volatilization during incubation was negligible, less than 0.3 mg N kg-1, and only 0.4-0.5% of ammonium-N was volatilized during incubation. Ammonium fixation by clay minerals and immobilization by soil microbes possibly account for the decrease in concentration of ammonium-N. From these results, we concluded that nitrogen loss by ammonium volatilization would be significantly low when acidic mine soils treated with livestock manure compost and liming materials were neutralized to slightly acidic condition. - COLLAPSE
    November 2018
  • Article

    Persistence of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes in Soil and Compost Amended Soil
    Kyu-Seok Jung*, Seung-Mi Seo, Hye-Jin Jeon, Bo-Reum Jeong, Eun-Jung Roh, Jae-Gee Ryu, and Kyoung-Yul Ryu
    Addition of animal manure to soil can provide opportunity for bacterial pathogens contamination of soil, water, and food. This study was conducted ... + READ MORE
    Addition of animal manure to soil can provide opportunity for bacterial pathogens contamination of soil, water, and food. This study was conducted to investigate the survival of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes in soil and compost amended soil under the selected environmental conditions. Soil and compost amended soil were inoculated with S. enterica, E. coli O157:H7, and L. monocytogenes. Soil and compost amended soil were incubated at 25°C and consistent moisture content. Samples had been collected during 200 days depending on the given conditions. S. enterica and E. coli O157:H7 survived over 200 days in soil and compost amended soil. L. monocytogenes persisted for 80 days in soil and for 160 days in compost amended soil, respectively. S. enterica and E. coli O157:H7 survived longer than L. monocytogenes at soil and compost amended soil. It is noted that S. enterica, E. coli O157:H7, and L. monocytogenes survived long in soil and compost amended soil. S. enterica, E. coli O157:H7, and L. monocytogenes survived longer in compost amended soil than in soil. Results from these studies provide useful information in identifying manure handling practices to reduce the risk of S. enterica, E. coli O157:H7, and L. monocytogenes transmission to foods produced in the presence of animal waste. - COLLAPSE
    November 2018
  • Article

    Studies on Potential Supply of Soil Organic Matter Using Phragmites australis in Reclaimed Land
    Sun Kim*, Yang-Yeol Oh, Jin-Hee Ryu, Su-Hwan Lee, and Jeong-Tae Lee
    This research was conducted to investigate the possibility of reeds (Phragmites australis) application to increase the low organic matter content in the ... + READ MORE
    This research was conducted to investigate the possibility of reeds (Phragmites australis) application to increase the low organic matter content in the reclaimed soil. Reed is not only a perennial vegetation native growing in the reclaimed land and a plant promising for soil organic resources as it is regenerated every year and also has a lot of biomass. In order to establish the system to increase the soil organic matter content, the reed residue was put into the soil using a tractor in different periods. After the growth, the reed straw was put into the soil at mid-September, mid-November and mid-February of the following year during 1st, 2nd and 3rd year. Soil chemistry showed no difference in pH and EC was slightly higher at constant three years of return plot. Carbon content increased at all treatments with increasing the number of application regardless of the treatment season. The amount of soil organic content increased with increasing the number of application comparing to 4.65 g kg-1 in soil with the preserved reed. This also increased to 8.01 g kg-1, 6.85 g kg-1 and 7.02 g kg-1 when the treatment was continued at mid-September, mid-November and mid-February for three years, respectively. This clearly showed that the application of reed straw to the soil was effective to improve soil fertility. Therefore, in order to increase the organic content of the reclaimed soil, it would be effective that the body part of reed is returned to the soil at mid-September of each year after the growth of reed is completed. - COLLAPSE
    November 2018
  • Article

    Effects of Nitrogen Source on Corn (Zea mays L.) and Leached Water Using Stable Nitrogen Isotope
    Ki In Kim*, Tae Jun Lim, and Kyeong Bo Lee
    The objective of this study was to evaluate nitrogen (N) source tracing using N stable isotope on corn (Zea mays L.) and ... + READ MORE
    The objective of this study was to evaluate nitrogen (N) source tracing using N stable isotope on corn (Zea mays L.) and leached water. Five nitrogen treatments were control (No nitrogen), 2 chemical N fertilizer (urea and slow released nitrogen (SRN), 1 cattle nitrogen manure (CM), and 1 oil cake from rapeseed (Brassica napus L.) after oil extraction. N rate was 200 kg N ha-1. The experiment was designed by a completely randomized block design with four replications. Lysimeter was filled with 4 kg of soil and corn was planted. Plant samples were collected at a growth stage of V6 and analyzed for total N and δ15N. Water samples were collected every week and analyzed for nitrate-N and δ15N. In this study, total N content at a growth stage of V6 corn plant ranged from 0.56% to 4.07%. N content was 0.56% for the control, 0.57% for the CM, 3.16% for the SRN, 3.19% for the oil cake, and 4.07% for the urea treatment. δ15N value at a growth stage of V6 corn plant ranged from 0.098‰ to -3.453‰. δ15N value in corn plant was -3.453‰ for the SRN treatment, -0.213‰ for the urea, 0.098‰ for the control, 2.935‰ for the oil cake, and 5.563‰ for the CM. Nitrate-N concentration in leached water was the lowest under control, followed by CM, SRM, oil cake, and nitrate-N concentration in leached was the highest under urea treatment. These results suggest different N mineralization from diverse N sources. Averagedδ15N isotope value in leached water changed from negative to positive. Averagedδ15N isotope under chemical N fertilizers such as urea and SRN was -16‰ and -15.0‰, respectively at the 5th week. Averagedδ15N isotope values for all N treatments changed during the experiment. These results indicate that δ15N isotope technique can be used for leached water samples to differentiate N sources. However, further research is needed to clarify the exact timing of sampling based on different N sources. - COLLAPSE
    November 2018
  • Article

    Estimation of Nutrient Balance in Field Crops Applied with Different Fertilization
    Seok Cheol Kim, Myung Sook Kim, Seong Jin Park, Seong Heon Kim**, and Chang Hoon Lee*
    Korea is one of those countries that have very high usage rates of chemical fertilizers per unit area of cropland. To reduce ... + READ MORE
    Korea is one of those countries that have very high usage rates of chemical fertilizers per unit area of cropland. To reduce the fertilizer application rate, a variety of agricultural polices has been introduced since the 1990s. The purpose of this study was conducted to find out the situation of fertilizer use on vegetable crops at 720 farmer’s fields located in 9 province area. Organic fertilizer application rates increased in major field crops. Chemical fertilizer application rates decreased in most of the field crops and vegetables surveyed; however, this reduction was concentrated in phosphate and potassium usage but not in nitrogen. In spite of this decrease, the fertilizer application levels to most crops were maintained at levels much higher than recommended. In the nutrient balance, which was calculated from the difference between input (chemical and organic fertilizers) and output (agricultural products), the nitrogen surplus were higher than recommendation fertilizer application rate. To reduce fertilizer utilization and to conserve environment, further reduction of fertilizer application is essential. - COLLAPSE
    November 2018
  • Article

    Status and Changes in Chemical Properties of Upland Soil in Gyeonggi Province
    Ahn-Sung Roh, Jung-Su Park, Young-Su Park, Ok-Jung Ju, Min-woo Shin, and Seong-Soo Kang*
    The chemical properties of upland fields in Gyeonggi province were monitored every 4 years from 2001 to 2017 in order to provide ... + READ MORE
    The chemical properties of upland fields in Gyeonggi province were monitored every 4 years from 2001 to 2017 in order to provide basic information for soil fertility management of upland fields. In 2017, the soil chemical properties of upland fields were 6.3 in pH, 22 g kg-1 in organic matter (OM), and 651 mg kg-1 in available phosphate (Avail. P2O5). Exchangeable (Exch.) potassium (K), calcium (Ca) and magnesium (Mg) were 0.83, 6.2 and 1.7 cmolc kg-1, respectively, and electrical conductivity (EC) was 0.86 dS m-1. In the long-term analysis, the contents of OM, Exch. Ca and pH of upland soils showed increasing tendency. However, the contents of Avail. P2O5 tended to decrease, and there were no significant changes in the contents of Exch. K and EC. The optimal range of pH of upland fields changed to 45% in 2001, 48% in 2005, 53% in 2009, 51% in 2013 and 47% in 2017. The optimal range of OM was 41% in 2001 and 2005, 40% in 2009, 33% in 2013, and 43% in 2017, respectively. The optimal range of Avail. P2O5 content increased from 19% in 2001 to 23% in 2005, but decreased to 15% in 2009 and increased to 22-23% in 2013 and 2017. The optimal range of Exch. K tended to decrease, showing 26% in 2001, 26% in 2005, 23% in 2009, 20% in 2013 and 19% in 2017. Therefore, in order to maintain the soil chemical properties of the upland soil in an appropriate range, it is necessary to fertilize the lime and fertilizer by the soil test. Also soil management such as the cultivation of green manure crop or application of rice straw and compost will be necessary to increase the organic matter content of upland soil. - COLLAPSE
    November 2018
  • Short Communication

    Optimum Range on Soil Physical Indicators Under Plastic Film House
    Yongseon Zhang, Heerae Cho*, Kyunghwa Han, Junghun Ok, Seonah Hwang, and Kangho Jung
    The water and nutrients in the soil can be absorbed by the crop root. The soil physical properties affect the growth and ... + READ MORE
    The water and nutrients in the soil can be absorbed by the crop root. The soil physical properties affect the growth and penetration of crop root. The objectives of this study were to determine soil physical indicators that could inhibit the crop growth under plastic film house, and to establish the appropriate soil physical criterion depending on crop types. The soil physical (including effective rhizosphere, soil three phase, and bulk density) and chemical (including pH, EC, organic matter content, and available phosphate) properties were investigated in the mainly cultivated area for greenhouse crops including lettuce, strawberry, cucumber, tomato, oriental melon, and water melon from 2015 to 2017. For plastic film house, soil physical indicators were commonly chosen as bulk density, air porosity, and effective root depth. The optimum ranges for plastic film house soil were as follows; deeper than 50 cm for effective root depth, less than 1.5 Mg m-3 for bulk density and more than 10% gas phase. - COLLAPSE
    November 2018
  • Review Article

    The Research Review of Soil Ecosystem Services
    Byungkeun Hyun*, Changhun Lee, Sangho Jeon, Sukyoung Hong, and Youngsun Zhang
    Recently, there is growing interest in agricultural public service function. Studies on soil ecosystem services in addition to its agricultural multi-functionality are ... + READ MORE
    Recently, there is growing interest in agricultural public service function. Studies on soil ecosystem services in addition to its agricultural multi-functionality are underway. Ecosystem services and agricultural multi-functionality have a common denominator of soil. To extend the concept, scope, and context of agricultural public services, it can be extended on the basis of soil functions. Therefore, the results of ecosystem services research related to soil are summarized. Recently, ecosystem services are classified into four categories. Ecosystem services of FAO are divided into provisioning services, regulating services, supporting services, and cultural services. The provisioning services included crop production and water resource. Regulating services are soil related functions such as carbon sequestration, waste treatment, water purification, flood control, erosion prevention, and nutrient supply. Supporting services are biodiversity functions. Ecosystem services can be divided into annual value and total asset value. The nutrient content function and carbon sequestration function can be evaluated at annual value, and also nutrient and carbon contents assessment can be evaluated by stock. They suggest additional soil functions as follows; the energy supply function through biomass, the rare earth supply, the production of medicines, the removing pollutant such as fine dust, drought resistance and soil nitrogen fixation. - COLLAPSE
    November 2018
  • Article

    Estimation for Red Pepper Growth by Vegetation Indices Based on Unmanned Aerial Vehicle
    Sang-Il Na, Chan-Won Park, Kyu-Ho So, Ho-Yong Ahn, Ki-Deog Kim, and Kyung-Do Lee*
    Unmanned Aerial Vehicles (UAVs) are currently gaining a growing interest for agriculture applications due to its potential in precision agriculture such as ... + READ MORE
    Unmanned Aerial Vehicles (UAVs) are currently gaining a growing interest for agriculture applications due to its potential in precision agriculture such as the identification of weeds and crop production issues, diagnosing nutrient deficiencies, and the prediction of biomass and yield. This study reports on the development for estimating the growth parameters of red pepper. The red pepper field using UAV was studied, and image analysis technologies were studied to develop growth estimation model from acquired images. We used the normalized difference vegetation index (NDVI) that reflects the crop conditions, and vegetation fraction (VF) for 2 major cultivation regions from 2016 to 2017. For this study, UAV imagery was taken at Goesan and Jeongeup regions ten times from June to September during the red pepper growing season. Two plant growth parameters, plant height (P.H.) and fruit set (F.S.) were measured for ten plants per plot for each field campaign. A multiple linear regression model was carried out by using the NDVI and VF extracted from UAV image. As a result, in the case of the P.H. the coefficient of determination was 0.805 and the root mean squared error of measurement was 8.140 cm. And for the F.S., the coefficient of determination was 0.979 and the root mean squared error of measurement was 2.407. These results will also be useful for determining the UAV imagery necessary to estimate growth parameters of red pepper. - COLLAPSE
    November 2018
  • Article

    Yield and Antioxidant Activity of Vegetable Crops Under Salt Affected Greenhouse Soil in Saemangeum Reclaimed Land
    Hyeonsoo Jang, Jong-Tak Youn, Seunghyun Ahu, Uk-Han Kim, Won-Yeong Choi, and Hui-su Bae*
    This study was conducted to examine the yield and antioxidant activity of vegetable crops under the salt affected greenhouse soil in order ... + READ MORE
    This study was conducted to examine the yield and antioxidant activity of vegetable crops under the salt affected greenhouse soil in order to evaluate the possibility of greenhouse farming in “Saemangeum reclaimed land”. Field experiment was conducted on a sandy loam soil and four different vegetable crops, Swiss chard (Beta vulgaris L.), Kale (Brassica oleracea ver. acephala), Red mustard (Brassica juncea L.), and Endive (Cichorium endivia L.) were cultivated. In the third year of the experiment, the soil salinity dramatically increased up to 23.5 dS m-1 from 2.2 dS m-1 in the first year of the experiment due to the resalinization of soil. The cumulative yield was 2,675 kg 10a-1 (Endive) > 2,560 kg 10a-1 (Red mustard) > 1,819 kg 10a-1 (Kale) > 1,795 kg 10a-1 (Swiss chard). Yield was inversely correlated with soil salinity (R2 = 0.71-0.77) but the red mustard was not significantly correlated with soil salinity. Both DPPH free radical activity and total phenol content were higher with red mustard. K/Naleaves ratio as an indication of the salt tolerance was in the order of Red mustard > Endive ≥ Swiss chard ≥ Kale. - COLLAPSE
    November 2018
  • Article

    Suppressive Effect of Bacillus amyloliquefaciens KL87 on Alternaria Blight of Ginseng
    Ye-Ji Yoon, Jeong-Su Jeong, Jae-Hee Won, Jin-Ho Joo, and Kwang-Jae Lee*
    Biological control of plant disease using microorganisms such as Bacillus, Trichoderma and Streptomyces is alternative method which can reduce disease in ginseng ... + READ MORE
    Biological control of plant disease using microorganisms such as Bacillus, Trichoderma and Streptomyces is alternative method which can reduce disease in ginseng cultivation. Antagonistic microorganisms can replace chemical agent, and reduce yield losses caused by several pathogens. The purpose of this study was to develop eco-friendly microbial agents and application technologies for the safe production of ginseng through control of ginseng aerial disease. For the selection of antagonistic microorganisms to control ginseng aerial disease, soil samples were collected from ginseng cultivation field, and 260 kinds of bacterial microbes were isolated. Among the 260 isolated microbes, KL87 strain suppressing the growth of ginseng pathogenic bacteria, Alternaria panax and Botrytis cinerea, was selected. As a result of 16S ribosomal RNA sequence analysis, KL87 strain was identified as Bacillus amyloliquefaciens. Furthermore, biochemical characteristics of KL87 strain showed high identity (99%) with Bacillus amyloliquefaciens. In the ginseng cultivation field test, Bacillus amyloliquefaciens KL87 reduced the occurrence of ginseng Alternaria blight by 75.9%. These results strongly suggested that Bacillus amyloliquefaciens KL87 could be used as microbial agents for replacement of chemical agent. - COLLAPSE
    November 2018
  • Short Communication

    Effects of Agro-machine Operating Period on Soil Physical Properties in Upland Fields
    Hee-Rae Cho and Kyung-Hwa Han*
    The subsoil compaction by heavy agro-machine is an ongoing cumulative process and threat in sustainable agriculture, especially exchange land use. The knowledge ... + READ MORE
    The subsoil compaction by heavy agro-machine is an ongoing cumulative process and threat in sustainable agriculture, especially exchange land use. The knowledge concerning the effects of agro-machine on soil physical properties in upland is necessary in arable soil management. The purpose of this study is to assess soil physical properties by heavy agro-machine operating period in upland. The choice of target soils was based on soil series, which preferentially have larger area in Korean upland field, including ranking 1st to 29th. Investigated sites of chosen soil series were designated at mainly distributed area of them. The soil physical properties include plow pan depth, bulk density, soil hardness and saturated hydraulic conductivity. From the investigation, soils with heavy agro-machine longer than 10 years, showed higher plow pan thickness, bulk density and hardness, and shallower surface soil depth than soils with heavy agro-machine shorter than 9 yrs. The value of plow pan thickness, bulk density, hardness, and surface soil depth is 19.8 cm, 1.54 Mg m-3, 21.8 mm and 16.9 cm in front one and 15.2 cm, 1.48 Mg m-3, 19.3 mm and 18.1 cm in back one. Especially fine silty and heavy clayey upland soils had an increase of plow pan thickness and decrease of saturated hydraulic conductivity by longer use of heavy agro-machine when classified by different soil textural families and upland soil types. Therefore, periodic improvement of physical properties is needed for upland soil management in the long-term point of view. - COLLAPSE
    November 2018
  • Article

    Evaluation of Evapotranspiration in Different Paddy Soils Using Weighable Lysimeter Before Flooding Stage
    Dong-Jin Kim, Kyung-hwa Han, Yong-seon Zhang, Hee-rae Cho, Seon-ah Hwang, Jung-hun Ok*, Kum-Sik Choi, and Jung-soon Choi
    Water is closely linked to agricultural productivity and is an essential resource for agriculture. Climate change and drought are causing water scarcity, ... + READ MORE
    Water is closely linked to agricultural productivity and is an essential resource for agriculture. Climate change and drought are causing water scarcity, and that has an enormous impact on agricultural productivity. Efficient water management methods are needed to prepare for water shortages. The lysimeter is well known as a facility for precisely measuring water and nutrient movement in the soil. Therefore, this study was conducted to investigate the evapotranspiration of different paddy soils using weighable lysimeter and to evaluate the relationship between the evapotranspiration estimated by weighable lysimeter and the reference evapotranspiration estimated by FAO Penman-Monteith equation and Hargreaves equation. This study was performed in lysimeter facility located at the National Institute of Agricultural Sciences, Rural Development Administration, and used lysimeter weight values and meteorological data measured from 1st January to 30th April in 2018. The daily evapotranspiration estimated by the lysimeter was ETLY, the reference evapotranspiration estimated by FAO Penman-Monteith equation was ETPM, and the reference evapotranspiration estimated by Hargreaves equation was ETHS. ETLY showed that loam (L) was higher than that of sandy loam (SL) and silty clay loam (SiCL). The accumulated evapotranspiration from 1st January to 30th April in 2018 was in the order of L (235 mm) > SL (231 mm) > SiCL (192 mm). Solar radiation showed a higher coefficient of determination (R2) than mean temperature in the correlation between the meteorological data and ETLY. The relationship between ETLY and ETHS showed a relatively low coefficient of determination, whereas the coefficient of determination in the relationship between ETLY and ETPM showed relatively high fitness for SiCL (0.631), L (0.860) and SL (0.884). Precise measurement and management of soil moisture using lysimeter are expected to be possible. - COLLAPSE
    November 2018
  • Short Communication

    Seasonal and Diurnal Change of NDVI from UAV Imagery in Clear Day Condition
    Kyung­Do Lee, Chan-Won Park, Kyu-Ho So, Ho-yong An, and Sang­Il Na*
    Recent advanced UAV (Unmanned Aerial Vehicle) technology supply new opportunities for estimating crop condition using high resolution imagery. The objective of this ... + READ MORE
    Recent advanced UAV (Unmanned Aerial Vehicle) technology supply new opportunities for estimating crop condition using high resolution imagery. The objective of this study was to analyze the change of vegetation index in UAV imagery according to sun altitude. This study was conducted using a fixed-wing UAV, called Ebee, with Cannon S110 camera from November 2017 to September 2018 in the grass experiment of National Institute of Agricultural Sciences on a clear day. As a result, the NDVI (Normalized Difference Vegetation Index) of UAV imagery decreased after 9 a.m. and showed a minimum value at 13 a.m. and increased since then. The solar zenith angle and the NDVI of UAV imagery showed a positive linear relationship. Therefore, in order to quantitatively compare and analyze the time series vegetation index, it is necessary to establish a UAV flight plan considering the change of solar zenith angle. It is thought that it will be necessary to examine cloudy days with various crop in the future. - COLLAPSE
    November 2018
  • Short Communication

    Analysis of Spectral Reflectance Characteristics of Forage Crops
    Sang-Il Na, Chan-Won Park, Kyu-Ho So, Ho-Yong Ahn, and Kyung-Do Lee*
    The objective of this study was to investigate the basic relationships between spectral reflectance and growing period of forage crops. Ground-level spectral ... + READ MORE
    The objective of this study was to investigate the basic relationships between spectral reflectance and growing period of forage crops. Ground-level spectral reflectance was collected in the field experiment containing plots of rye, whole-crop barley and Italian-ryegrass (IRG). We observed that spectral reflectance increases with SSC, first at the visible range, then in the red-edge range, and finally, in the near-infrared range; a characteristic maximum reflectance variation appears at 730-760 nm. The first derivative of reflectance spectra showed several peaks that were dependent in different degrees on chlorophyll concentration in the forage crops. Experimental data recorded on forage crops during the growing season are in good agreement with previous theoretical results. - COLLAPSE
    November 2018
  • Short Communication

    Growth and Yield Characterization of Soybean (Glycine max L.) and Adzuki Bean (Vigna angularis L.) Cultivated from Paddy Fields with Different Topographic Features
    Hyen Chung Chun*, Ki Yuol Jung, Young Dae Choi, Sanghun Lee, and Hang Won Kang
    In Korea, the largest agricultural lands are paddy fields which have poor infiltration and drainage properties. Recently, Korean government pursuits cultivating upland ... + READ MORE
    In Korea, the largest agricultural lands are paddy fields which have poor infiltration and drainage properties. Recently, Korean government pursuits cultivating upland crops in paddy fields to reduce overproduced rice in Korea. In order to succeed this policy, it is critical to understand topographic information of paddy fields and its effects on upland crops cultivating in paddy field soils. The objectives of this study were characterizing growth properties of soybean and adzuki bean from paddy fields with three soil topographic features and soil water effects which were induced by topographic features on sesame and perilla. The crops were planted in paddy fields located in Miryang, Gyeongnam with different topographies; mountain foot slope, local valley and alluvial plain. Soil water contents and groundwater levels were measured every hour during growing season. The paddy field of mountain foot slope was significantly effective to alleviate wet injury for soybean and adzuki bean in paddy fields. The paddy field of mountain foot slope decreased average soil water content and groundwater level during cultivation. Stress day index (SDI) from the alluvial plain paddy field had the greatest values from both crops and the smallest from ones of mountain foot slope. This result meant that soybean and adzuki bean had the smallest stress of soil water from the paddy field of mountain foot slope and the greatest from one of alluvial plain. It is important to consider topography of paddy fields to reduction of wet injury and to increase in yields. - COLLAPSE
    November 2018
  • Article

    Effect of Application Levels of Inorganic Fertilizer with Biochar on Corn Growth in an Upland Field
    Se-Won Kang, Won-Jun Lee, Hong-Guk Jeong, Jae-Hyuk Park, Ju-Hee Lee, Jin-Ju Yun, Sang Yoon Kim, Dong-Cheol Seo, and Ju-Sik Cho*
    This study was conducted to evaluate the effect of application levels of inorganic fertilizer (IF) with corn waste biochar (BC) for corn ... + READ MORE
    This study was conducted to evaluate the effect of application levels of inorganic fertilizer (IF) with corn waste biochar (BC) for corn cultivation in an upland field (34° 94ʹ 24ʺ N, 127° 56ʹ 55ʺ E). The IF (N-P-K 14.5-3.0-6.0 kg 10a-1) was applied at levels of 25%, 50%, 75%, and 100% of standard amount with BC (BC+IF25, BC+IF50, BC+IF75, and BC+IF100, respectively), and Cn (control), BC and IF treatments were added in this study. The BC was application of 500 kg 10a-1 at 20 days before corn sowing. The mean biomass productivity of corn plants, when grown under Cn, BC, IF, BC+IF25, BC+IF50, BC+75, and BC+IF100 treatment conditions, were 1.82, 2.21, 2.74, 2.40, 3.12, 3.73, and 4.05 kg m-2, respectively. The corn length was 14.6-18.3 cm ear-1 in all treatments, and the total weight of corn increased in the order BC+IF100 ≒ BC+IF75 > BC+IF50 > IF > BC ≒ BC+IF25 > Cn treatments. The corn productivity was highest (3.97 kg m-2) in the BC+IF100 treatment. The corn grain yields in BC+IF50, BC+IF75, and BC+IF100 treatments increased by 145, 129, and 103% respectively, over that in the IF treatment. Based on our results, the minimum IF application level using biochar for corn cultivation was N of 7.25 kg 10a-1, P of 1.5 kg 10a-1, and K of 3.0 kg 10a-1, respectively. Therefore, proper application of inorganic fertilizer with biochar is effective at improving corn cultivation and can benefit the soil environment. - COLLAPSE
    November 2018
  • Article

    Water Balance for Chinese Cabbage in Spring Season with Different Upland Soils Evaluated Using Weighable Lysimeters
    Jung-hun Ok, Kyung-hwa Han, Ye-Jin Lee, Yong-seon Zhang, Hee-rae Cho, Seon-ah Hwang, Soon-sun Kim, Jin-hee Lee, and Dong-Jin Kim*
    In this study, we evaluated the water balance for Chinese cabbage cultivation in spring season with different upland soils using weighable lysimeter, ... + READ MORE
    In this study, we evaluated the water balance for Chinese cabbage cultivation in spring season with different upland soils using weighable lysimeter, and investigated the evapotranspiration at different growth stage of Chinese cabbage and total inflows and outflows as affected by soil texture . Outflows such as percolation and evapotranspiration were different with soil type (i.e., soil texture), while no significant difference for total inflows. It was also shown that the least amount of drainage in the loam with high bulk density and the largest amount of drainage in silty clay loam. This is thought to be the result of the vertical movement of water through macropore along with the cracking of the soil that was created by repeated shrinkage and expansion of the silt clay loam during the winter season. The evapotranspiration during the Chinese cabbage cultivation period was the highest in loam, and this is probably due to the large leaf area of the Chinese cabbage grown in loam and high biomass weight. Based on the data obtained using the weighable lysimeter, water movement and water balance of the upland soil could be evaluated. Our study will contribute to the development of national factors in Korea for the estimation of the water management for upland crops with production and accumulation of several years data. - COLLAPSE
    November 2018
  • Short Communication

    The Use of Useful Statistics of Soil Texture According to Standardized Depth Between Two Digital Soil Maps
    Yeonkyu Sonn*, Woori Go, Sangho Jeon, Byungkeun Hyun, Minsan Im, and Sungang Yun
    In Korea, a soil survey was conducted at a scale of 1: 5,000, and classification was performed based on USDA's Soil Taxonomy. ... + READ MORE
    In Korea, a soil survey was conducted at a scale of 1: 5,000, and classification was performed based on USDA's Soil Taxonomy. Now the computerized soil map is in use. DSM work has been performed based on the soil map. Even so far, we have been building DBs in various ways and trying DSM continuously. Since 2002, data can be found on the Internet through the Korean soil information system (heugtoram) and it is also available on mobile system. Based on the 1: 5,000 scale, various detailed thematic maps are produced. The useful information has been provided to farmers, policy makers, and researchers. The basic data of the soil was used around 1970. In 2014, we tried to compare it with the newly upgraded data. R program was used to generalize the texture data (sand, silt & clay content) of soil depth. Conversion of vector data (polygon, shp file) of soil map into raster data (30 m) was performed. Soil texture data for depth were generalized to 0-5, 5-15, 15-30, 30-60, 60-100, 100-200 cm for sand, silt and clay contents and tried to compare the difference of the results. The number of polygons was the same in both sand, silt and clay contents. The total number of polygons was 1,381,126 and the number of polygons contained in the soil series was 1,308,700. As the depth increased, soils with rocks or shallow soils were not shown. Mean, standard deviation and mean deviation were analyzed for comparisons of DSM. The standard deviations were very variable and difficult to compare. The results were different from those obtained when the mean deviation was used. To compare the differences between the two maps, by converting the state in which a negative number exists to an absolute value, the average deviation to be performed is more uniform. - COLLAPSE
    November 2018
  • Article

    Agricultural Soil Management Practices by Assessing the Soil Chemical Properties of Plastic Film Houses in Korea
    Myung-Suk Kong, Yoo-Hak Kim, Dong-Jin Kim, Seong-Soo Kang, Eun-Jin Lee, Goo-Bok Jung, and Ha-il Jung*
    This study was designed to assess the changes of soil chemical properties in the intensive plastic film houses and develop sustainable agricultural ... + READ MORE
    This study was designed to assess the changes of soil chemical properties in the intensive plastic film houses and develop sustainable agricultural practices on soil management. Soil testing data (158,227), uploaded on Korean soil information system (http://soil.rda.go.kr) from 2006 to 2015, were analyzed. The study showed that soil pH and organic matter (OM) have kept within the standard ranges and electrical conductivity (EC), available phosphate (Avail. P2O5) and exchangeable (Exch.) cations (K, Ca, and Mg) were increased from 2006 to 2015. Relative frequency distribution were 57% for pH 6.5<, 32% for OM 15-25 g kg-1 in 2015, and the contents of Exch. K, Ca, and Mg in 2015 was the highest in 0.2-0.5, 6.0-9.0, 2.0-4.0 cmolc kg-1, respectively. Soil pH, Exch. Ca and Mg were high levels in oriental melon growing region and OM, Avail. P2O5 and Exch. K were sufficient in tomato and pepper field. More than half of the farmlands below the standard range of OM contents and the ratio of high range in Exch. Ca and Mg were increased. Soil testing results including pH, OM and Exch. cations are essential parameters for crop growth. According to the results of the soil testing, adequate amount of fertilizer, compost and soil amendment should be supplied to ensure stable crop productivity. - COLLAPSE
    November 2018
  • Article

    The Changes of Soil Carbon as Affected by Several Kinds of Organic Material in Upland Soil
    Hyeon-Suk Cho*, Myung-Chul Seo, Jun-Hwan Kim, Wan-gyu Sang, Pyeong Shin, and Jaekyeong Baek
    Organic matter is a substance that contains carbon. When applied to soil, it can improve the physical and chemical properties of soil ... + READ MORE
    Organic matter is a substance that contains carbon. When applied to soil, it can improve the physical and chemical properties of soil and supply nutrients to plants. Also, it is decomposed in soil due to microbe activity, or absorbed and utilized by crops. The remaining differential to materials is accumulated in the soil and increases the level of organic matter in soil. Given that the humidity and temperature are appropriate, and there are energy sources favorable for microbe activity, the decomposition rate is higher, thus resulting in the increase of the nutrient availability of crops. Therefore, we analyzed the types of carbon content according to time while cultivating beans in soil with 4 different kinds of organic matter applied. Total carbon content (TC) was higher in organic matter application than in control (non- organic matter). Among the other organic matters, it was especially high in livestock manure compost (LMC) application with 11.1 g kg-1. Hairy vetch (HV, 8.9 g kg-1), oil cake (OC, 8.9 g kg-1), and rice straw (RS, 8.2 g kg-1) did similar. According to soil carbon form, Humin carbon(HnC) had the highest total carbon contrast of 62.0 %, Humic acid carbon(HaC) had 19.6%, and Fulvic acid carbon(FaC) had 18.1%. This pattern was the same in both control and organic matter application. Every type of carbon was the highest in LMC application. TC levels were temporarily high in June, which was after organic matter application, and decreased. It was higher than any other organic matter application in LMC. HaC increased in May and June which was when the organic matter was applied, slightly decreased in July, and were the highest in LMC with TC. FaC slowly increased after organic matter application until March and slowly decreased afterwards. It was highest in LMC, and similar in HV, OC, and RC, which shows that it had the smallest difference of content between kinds of organic matter. HnC inclined to decrease slowly as time passed after organic matter application, but rapidly increased in July and June. Also, it was the highest in LMC, and similar in HV, OC, and RC. Therefore, it was concluded that LMC, which had a high level of humin carbon that is difficult to decompose, was the best for accumulating carbon in soil. - COLLAPSE
    November 2018
  • Article

    The Effect of Food Waste Compost on Chinese Cabbage (Brassica rapa var. glabra) and Tomato (Solanum lycopersicum L.) Growth
    Jae Hong Yoo, Young Don Lee, Khalid A. Hussein, and Jin Ho Joo*
    Composting of food waste might be effective way for food waste disposal which could be applied to improve soil properties in agricultural ... + READ MORE
    Composting of food waste might be effective way for food waste disposal which could be applied to improve soil properties in agricultural field. The purpose of this study is to evaluate the effect of food waste on two crops (Chinese cabbage, Tomato) compared to livestock manure. Seven different treatments (one livestock manure, two food wastes, one livestock manure + chemical fertilizer, two food waste + chemical fertilizer, and control) were applied to two crops . Treatment of livestock + chemical fertilizer and microorganism treated food waste +chemical fertilizer showed statistically significant differences on leaf width and root length of Chinese cabbage compared to other treatments. They showed highest values for these parameters. Value of four parameters (shoot length, total length, fresh weight and chlorophyll content) were highest with treatment of livestock + chemical fertilizer and microorganism treated food waste + chemical fertilizer for tomato growth. - COLLAPSE
    November 2018
  • Article

    Effect of Sprinkler, Surface Drip and Subsurface Drip Irrigation Methods on ‘Fuji’/M9 and ‘Fuji’/M26 Apple Orchards Growth, Soil Properties, and Water Consumption
    Seung Gab Han*, Gopal Selvakumar, Pyoung Ho Yi, and Seong Eun Lee
    Conventional irrigation methods require high amount of water to meet ‘Fuji’/M9 and ‘Fuji’/M26 apple orchards irrigation requirement. In this study, the efficiency ... + READ MORE
    Conventional irrigation methods require high amount of water to meet ‘Fuji’/M9 and ‘Fuji’/M26 apple orchards irrigation requirement. In this study, the efficiency of sprinkler, surface drip and subsurface drip irrigation methods on water use efficiency, tree growth, yield, and canopy volume were compared. Experiment I (‘Fuji’/M9 apple orchard) consisted of sprinkler, surface drip and subsurface drip irrigation methods. Subsurface drip irrigation method consumed 37% and 27% less irrigation water to maintain same matric potential compared to sprinkler and surface drip irrigation methods, respectively. In addition, subsurface drip irrigation method showed less sunburn fruits and contained less weed growth compared to sprinkler and surface drip irrigation methods. In experiment II (‘Fuji’/M26 apple orchard), subsurface drip irrigation method at different depths (0, 15 and 30 cm) were compared. The results showed that irrigation at 30 cm depth consumed 52% less water to maintain the same matric potential compared to 0 cm (or surface drip) irrigation. However, apple tree stem circumference, new shoot length and canopy volume were not significantly different between treatments. These results suggest that subsurface drip irrigation can be used as an efficient method to reduce the irrigation water in ‘Fuji’/M9 and 'Fuji'/M26 apple orchards and to reduce weed growth. - COLLAPSE
    November 2018
  • Article

    Effects of Long-Term Fertilization on Light and Heavy Fractions of Soil Organic Matter in Single Cropping Paddy Soils in Korea
    Kwang Seop Kim, Ki Do Park, Ki-Yuol Jung, Sung Hwan Oh, Min-Tae Kim, Sook Jin Kim, Jong-Seo Choi, Jun-Hong Park, and Man Park*
    Advanced understanding of SOC still requires further studies on diverse soils including a wide spectrum of paddy soils and agricultural practices. The ... + READ MORE
    Advanced understanding of SOC still requires further studies on diverse soils including a wide spectrum of paddy soils and agricultural practices. The objectives of this study were to investigate the effects of long-term fertilization on both light fraction (LF) and heavy fraction (HF) of soil organic matter and the relationships among total C, C/N ratio, clay content, and fertilization type in paddy soils. Compost application led to a significant increase in HF and consequently in C and N contents. Compost plots had a higher C/N ratio compared to those of treatments without compost in HF as well as LF. Correlation of C/N ratio to LF and HF was clearly separated into two groups as a boundary of about 9.5 of C/N ratio. These results clearly show that balanced fertilization together with composting could lead to synergic effects on enhancing C sequestration as well as plant nutrition in plow layer of paddy soils in Korea. - COLLAPSE
    November 2018
  • Article

    Characteristics of Growth-Stage-Based Nutrient Uptake of Lettuce Grown by Fertigation Supply in a Greenhouse
    Seul-Bi Lee*, Yang-Min Kim, Jwa-Kyung Sung, Ye-Jin Lee, and Deog-Bae Lee
    As fertigation facilities in a greenhouse have increased, information on the nutrient requirement along the plant growth stages is highly needed. This ... + READ MORE
    As fertigation facilities in a greenhouse have increased, information on the nutrient requirement along the plant growth stages is highly needed. This study investigated the nutrient uptake pattern of leafy lettuce cultivated in a pot filled with a sandy loam soil in a greenhouse from March to June in 2016 and to calculate the amount of nutrient supply with growth stages of lettuce by fertigation system. With different nitrogen (N) top-dressing supply levels (0.5N, 0.75N, 1.0N, and 1.5N) by soil NO3-N based recommendation, the characteristics of growth and nutrient uptake of lettuce along the growth stages have been evaluated. Soil NO3-N decreased along the growth stages, having no significant differences among N supply levels lettuce leaf growth showed linear growth patterns and there was no clear difference in growth and nutrient uptake among N supply levels. The growth of lettuce was 17%, 38%, and 64% of total accumulated growth of lettuce (dried weight, averaged N supply level) after 40 days, 50 days, and 60 days after seeding (DAS), respectively, reached to 38.9 kg 10a-1 at 70 DAS. Mineral uptake (N, P2O5, and K2O) of lettuce along the growth stages, showing different patterns with nutrient species, was characterized into increasing pattern in N uptake, steady-increasing pattern in P2O5 uptake, and step-like pattern in case of K2O uptake. With growth stages of lettuce, the N uptake was 26%, 17%, 20%, and 37% of total N uptake, 24%, 3%, 12%, and 50% in case of total P2O5 uptake, and 20%, 31%, 12%, and 34% of total K2O uptake. In conclusion, the scheduling of the fertigation nutrient supply designed on the basis of daily nutrient uptake and nutrient use efficiency by fertigation system could contribute to maintain stable productivity of lettuce and ameliorate the nutrient accumulation of greenhouse soil. - COLLAPSE
    November 2018
  • Article

    The Effects of Hairy Vetch Application on Soybean Yield and Soil Physico-chemical Properties Under Different Soil Textures
    Jongseo Choi*, Shingu Kang, Sukjin Kim, Jeong Hwa Park, and Woonho Yang
    Hairy vetch (Vicia villosa Roth) is an important green manure crop which decomposes rapidly in soil and releases significant amount of nitrogen ... + READ MORE
    Hairy vetch (Vicia villosa Roth) is an important green manure crop which decomposes rapidly in soil and releases significant amount of nitrogen to subsequent crops. The incorporation of hairy vetch also contributes to organic matter accumulation and improvement of soil structure. However, appropriate management techniques for soybean production using hairy vetch have not been well studied yet. This study was conducted to investigate the effect of hairy vetch on the soil physico-chemical properties and soybean yield in different soil textures. The experimental soils were classified as clay loam, loam, sandy loam and sand. Hairy vetch was incorporated into soils of different texture at three different rates before sowing of soybean. The amount of incorporated hairy vetch was calculated from the nitrogen content of the biomass which were equivalent to 50, 100, and 150% of the recommended N fertilization rate for soybean, respectively. The growth and yield of soybean in hairy vetch plots were higher than those in conventional plot in clay loam and sand, but they were similar in loam and sandy loam. Soybean yields in clay loam and sand increased along with increase of incorporated hairy vetch biomass. Addition of hairy vetch resulted in increased available P and decreased pH in all soils except loam. Hairy vetch plot showed increased soil water content at 5-10 cm depth in sand, which possibly affects the water availability to plant. In clay loam soil treated with hairy vetch, water content increased at 0-5 cm depth and decreased at 5-10 cm depth compared with conventional plot. This study shows that application of hairy vetch green manure improves soybean yield through the alteration of the soil physical property such as water holding capacity and permeability, especially in very coarse or fine-textured soils. - COLLAPSE
    November 2018
  • Article

    Adjustment of Soil pH and Redox Potential Using KOH and KMnO4 in Acidic Soils Applied with Immature Compost
    Eun-jin Lee, Myung-Suk Kong, Ha-il Jung, Goo-Bok Jung, and Yoo-Hak Kim*
    pH and pe are very helpful values for understanding soil environmental conditions. Particularly, it has a great influence on the form of ... + READ MORE
    pH and pe are very helpful values for understanding soil environmental conditions. Particularly, it has a great influence on the form of nutrients such as nitrogen. When pH+pe is less than 14.32, NO2- increases and NO2 (g) produced from NO2- harms crops. In this study, KOH, KMnO4, and sodium percarbonate (sp) were used to raise pH and pe to above the appropriate range (pH 6-7). While the pH was around 5 before the test, the pH was maintained at 6 or higher by all treatments until the end of the test (pH increment (ΔpH) after 5 days 1.0-2.5). pH+pe values were able to be corrected to 14.32 or more by KOH+KMnO4 treatments and sp treatment in drip irrigation and excessive treatment was good at furrow irrigation with easily reductive condition. Potassium (K), which is one of soil cation exchange capacity (CEC), acts as a strong base to increase the pH, so it is necessary to carry out the CEC measurement and titration test before the KOH+KMnO4 treatment. Mn2+ is decreased by the precipitation reaction with phosphate ion (H2PO4-) in the soil. Phosphate input will be helpful to supply phosphate necessary for crop growth and to prevent Mn excess. In addition, when determining the amount of reagent treated, it is considered that the soil osmotic pressure should be lower than the plant osmotic pressure so as not to cause wilted plant. - COLLAPSE
    November 2018
  • Article

    Introduction of On-site Soil Analysis and Diagnosis System
    Yoo-Hak Kim*, Myung-Suk Kong, Eun-Jin Lee, Seong-Soo Kang, Goo-Bok Jung, and Ha-Il Jung
    Crops must absorb all essential elements sufficiently, because a yield of crop is determined by the Minimum which is the growth limiting ... + READ MORE
    Crops must absorb all essential elements sufficiently, because a yield of crop is determined by the Minimum which is the growth limiting factor of Liebig's law of minimum. The minimum is determined by soil testing and recommended as a fertilizer corresponding to the amount of crop production for the crop period before cultivation but the amount of the fertilizer is supplied by farmers’ experiences on the growing condition of crop during cultivation. Owing to the diversity of soil chemical properties, soil must be categorized to be recommended the adequate amount of fertilizer. Therefore we categorized soil as 8 soil testing types with soil pH and soil organic matter (SOM) of Korean soil information system. We also set up the on-site soil analysis and diagnosis system in order to recommend the nutrients by soil testing during cultivation. The process of system was composed of three steps: 1) analyzing chemical properties of pH and Eh and nutritional properties of N and P and osmotic properties of EC or sum of nitrate and sulfate and chloride, 2) diagnosing soil condition as one of 64 kinds of soil conditions with categorizing with 4 chemical properties and 8 nutritional status and 2 osmotic aspects, 3) recommending the amount of minimum according to the soil condition and soil testing type and how to supply fertilizers by a series of pH buffer and fertilizer and water. - COLLAPSE
    November 2018
  • Article

    Micro-sprinkler Irrigation Uniformity as Affected by Different Water Pressure and Outlet Intervals
    Sangho Jeon, Seonah Hwang, Yeonkyu Sonn, Byungkeun Hyun, Woori Go, Sungang Yun, and Kyunghwa Han*
    This study carried out to evaluate the water distribution uniformity of micro-sprinkler to improve water utilization efficiency. The water quantity and the ... + READ MORE
    This study carried out to evaluate the water distribution uniformity of micro-sprinkler to improve water utilization efficiency. The water quantity and the water pressure were measured according to the spacing of micro-sprinkler and adjusting the applied water pressure. The results showed that the spacing of the micro-sprinklers a decisive influence on the distribution uniformity, but the change in hydraulic pressure did not have a significant effect. The water quantity was reduced by 22.7 ± 1.6 % when the water pressure dropped 100 kPa. Each micro-sprinkler has different spray pattern. The wetted radius was measured about 4 m. A peak was found within a meter radius from the center of the micro-sprinkler and gentle slope between 2 - 4 m. The appropriate spacing is 2 - 4 m depend on micro-sprinkler and purpose of the system. The results would be used in micro-sprinkler system guideline and design for best water distribution uniformity. - COLLAPSE
    November 2018
  • Article

    A Study on Efficient Management Strategy for Soil Erosion
    Joung-Bae Hwang*, Nam-Chan Kim, Chang-In Lim, and Yoon-Min Kang
    Soil value was estimated 26 trillion Korean won and recent climate change due to global warming is highly affecting soil erosion. Especially, ... + READ MORE
    Soil value was estimated 26 trillion Korean won and recent climate change due to global warming is highly affecting soil erosion. Especially, about 10% of surface soil was annually eroded because of massive construction in Korea. Main purpose of this research was i) to investigate occurrence, mechanism, affecting parameters of soil erosion especially focused on wind erosion and ii) to conduct wind tunnel experiment for evaluating feasibility of dry fog system in stabilizing wind erosion. Result of wind tunnel experiment showed that wind erosion could be reduced about 22-38% after applying dry fog system. Two parameters, soil particle size and spreaded water drop size, are main parameters to affect efficiency of wind erosion stabilization and smaller water drop size is more effective to prevent wind erosion than soil particle size. In terms of wind erosion management, evaluation of soil erosion should be conducted for environmental impact assessment (EIA) when land usage is changed or massive construction was conducted. Since there is no evaluation form of soil erosion in EIA, not only soil erosion but also wind erosion evaluation should be included in the EIA. In addition, transaction of soil and rock open portal recycle system (TOCYCLE) could be utilized to recycle surface soil and consequently, prevent wind erosion and conserve value of soil. Overall, dry fog system is an effective technique for wind erosion preventing system and it could be combined with natural and/or artificial soil conservation system to enhance wind erosion prevention. Furthermore, policy and management system for preventing soil erosion should be thoroughly reviewed to make better soil conservation. - COLLAPSE
    November 2018