• Article

    Soil Neutralizer Selection for Rehabilitation in the Acid Soil of Abandoned Metal Mine Using Miscanthus sinensis Anderss.
    Mun Ho Jung, Jin Soo Lee, and Won Hyun Ji
    The objectives of this study were to investigate the effects of soil neutralizing treatments on soil characteristics and growth of Miscanthus sinensis ... + READ MORE
    The objectives of this study were to investigate the effects of soil neutralizing treatments on soil characteristics and growth of Miscanthus sinensis Anderss., in the acid soil of abandoned metal mine for selection of proper neutralizer. The kinds of soil neutralizers were acid mine drainage sludge 10%, 20%, bottom ash 1%, 2%, fly ash 1%, 2%, Waste-Lime+Oyster 1%, 2% and compost. The most effective neutralizers were acid mine drainage sludge 10%, 20% and Waste-Lime+Oyster 1%. Waste-Lime+Oyster 2% was considered second effectiveness. Bottom ash 2% showed promoting shoot growth of M. sinensis Anderss., acid mine drainage sludge 20% for root growth. But the case of total growth, bottom ash 1%, 2% and acid mine drainage sludge 20% were the most promoting treatment. Soil pH, C/N ratio and available P showed effective to shoot growth, while root growth was influenced by soil pH and available P. In case of total, soil pH affected. After consideration to growth of M. sinensis Anderss., soil characteristics which affected to growth of M. sinensis Anderss., and soil characteristics of each treatment, it is applicable of bottom ash 1% firstly, and bottom ash 2% secondly for rehabilitation in abandoned metal mine. However, it is necessary to consider for the cost of neutralizer before the application of rehabilitation. Soil chemical characteristics according to treatments (<i>p</i> < 0.05).
    Mine pH TOC Total-N C/N ratio Av.P2O5 Soil dehydrogenase activity
    unit % % mg kg-1 ug TPF g-1 24 h-1
    AMDS 10% 7.8a 0.49bc 0.05c 10.6a 1.0e 4.0ab
    AMDS 20% 7.7a 0.44cde 0.04c 10.9a 0.4e 3.6bc
    Battom Ash 1% 5.4d 0.46bcde 0.05bc 9.1ab 22.8bc 4.3a
    Battom Ash 2% 5.1d 0.40ef 0.06b 7.0abc 29.0b 3.3bc
    Fly Ash 1% 4.8cd 0.51b 0.05bc 10.4a 19.8bc 3.2bc
    Fly Ash 2% 5.1d 0.47bcd 0.06b 8.4abc 22.3bc 3.0c
    Waste-Lime+Oyster 1% 7.0bc 0.41de 0.04c 9.7ab 15.1cd 3.6bc
    Waste-Lime+Oyster 2% 7.3ab 0.35f 0.04c 9.0ab 21.5bc 3.5bc
    Compost 6.5c 0.79a 0.13a 6.3c 96.3a 3.7bc
    Control 4.4e 0.20g 0.04c 11.0a 6.5de 3.7bc
    AMDS : Acid Mine Drainage Sludge.
    - COLLAPSE
    August 2020
  • Article

    Effects of Green Manure-Maize Rotation on Phosphorus Uptake of Crop and Decrease in Phosphorus Accumulation in Organic Upland Soil
    ho-Rong Lee, Yura Oh, Kwang-Lai Park, Jeong-Lai Cho, Nan-Hee An, and Sang-Min Lee
    Phosphorus (P) easily accumulates in farmland soil due to their high affinity to cations and clay, and thus their use efficiency of ... + READ MORE
    Phosphorus (P) easily accumulates in farmland soil due to their high affinity to cations and clay, and thus their use efficiency of crop is low. Green manure-maize rotation system might be an efficient measure to reduce P accumulation in organic farmland by improving P uptake of crops. This study was conducted to investigate the effects of green manure-maize rotation on P uptake of maize and excess P removal in organic upland soils. Maize mono cropping and green manure-maize rotation systems (barley (B), hairy vetch (H), mixture of B and H) were established in organic farmland, and the experiments were conducted for 2 years without additional nutrients application. Green manure had a significant impact on maize grain production. Maize P uptake increased with the increased rate of hairy vetch seeding. Water soluble P content in soil was further reduced in green manure-maize rotation systems compared to the mono cropping. The results suggest that green manure-maize rotation system (except barley) without nutrient supplement increases P uptake of maize and thus decreases soil P accumulation. Maize P uptake significantly increased with the increased rate of hairy vetch seeding. Water soluble P content in soil was reduced more in green manure-maize rotation system than mono cropping system. CON is mono cropping (no green manure); B is barley single; B2H1, B1H1, and B1H2 were mixture of B and H at the ratio of 2:1, 1:1, and 1:2, respectively; H is hairy vetch single. - COLLAPSE
    August 2020
  • Article

    Changed Stoichiometric Ratios of Carbon, Nitrogen, and Phosphorus in Runoff Water from Maize Upland Fields by Rice Straw Cover
    Se-In Park, Hye In Yang, Hyun-Jin Park, Bo-Seong Seo, Young-Jae Jeong, and Woo-Jung Choi
    Soil and nutrient loss through runoff water from upland fields is a critical non-point pollution pathway in agricultural areas. Surface cover with ... + READ MORE
    Soil and nutrient loss through runoff water from upland fields is a critical non-point pollution pathway in agricultural areas. Surface cover with crop residue is commonly recommended to reduce soil and nutrient loss; however, there is a high possibility of increased runoff loss of dissolved organic C (DOC) through decomposition of crop residue though relevant studies are lacking. The changed stoichiometric ratios of carbon (C), nitrogen (N), and phosphorus (P) such as C/N and C/P of runoff water by increased DOC loss can be indicators of the impact of surface cover on water quality. In this study, the effects of rice straw cover on C/N and C/P of rainfall-derived runoff water (totally six events) from upland maize fields were investigated. The C/N and C/P in the sediment-bound form were not affected by straw cover throughout the six rainfall events, across the control and covered plots. The C/N and C/P in dissolved forms varied from 0.9 to 3.3 (1.8 ± 0.4) and from 4.6 to 43.4 (12.1 ± 2.8) for control plot and from 1.8 to 37.1 (8.7 ± 0.8) and from 6.1 to 126.2 (44.4 ± 6.5) for covered plots, respectively. Surface cover increased (p < 0.05) the mean C/N (by 4.8 fold) and C/P (3.7 fold) in the dissolved forms across the six events, and increased C/N and C/P were evident in the late period of long-lasting rainfall events when surface cover lost its capacity to reduce runoff. Therefore, surface cover of upland fields with crop residue may increase C/N and C/P of runoff water, and thus these stoichiometric ratios in water bodies surrounding the fields may be used as indicators of the influence of upland fields covered with crop residue on water pollution particularly in the late period of continuous rainfall. Rice straw surface cover of maize upland fields increased C/N and C/P in dissolved forms of runoff water from the fields due to increased export of dissolved C through straw decomposition. - COLLAPSE
    August 2020
  • Article

    Growth Responses and Changes of Soil Chemical Properties with Application Rate of Supplemented Biochar pellet as Slow Release Fertilizer during Tomato Cultivation
    Minjin Kim, Huiseon Kim, Seok-In Yun, Changkyu Lee, Dogyun Park, Myungsook Kim, and JoungDu Shin
    This experiment was conducted to select an optimum application rate of supplemented biochar pellet as slow release fertilizer during tomato cultivation. The ... + READ MORE
    This experiment was conducted to select an optimum application rate of supplemented biochar pellet as slow release fertilizer during tomato cultivation. The supplemented biochar pellet was made through pellet mill placed with a combination (4:6) of biochar and pig manure compost with spraying the N-P-K solution. The treatments consisted of control as the recommended application rates of fertilizers and pig manure compost, N 40%, N 50% and N 70% of the supplemented biochar pellet application based on the recommended application rates of nitrogen. The highest nitrogen balance was 80.1% in the N 40%, while the highest carbon balance was 80.8% in the N 50% during tomato cultivation. Mehlich III extractable P2O5 contents in the N 50% was highest among the supplemented biochar pellet treatments. The highest stem diameter and plant height were 10.7 mm and 169.3 cm in the N 70% at 90 days after transplanting. The fresh weight of fruit was not significantly different between the control and N 50% treatment. Therefore, it might be considered that an optimum application rate was N 50% with considering chemical properties of soil and growth responses to application of supplemented biochar pellet during tomato cultivation. Responses of nitrogen balance to application of blended biochar pellets for tomato cultivation.
    Treatments* Input amounts of total nitrogen (g pot-1) Residual amounts of total nitrogen (g pot-1) Nitrogen balance
    Control 6.2 7.0 ± 0.1 △ 12.9 ± 1.6
    N 40% 5.3 4.2 ± 0.3 80.1 ± 5.7
    N 50% 5.4 3.5 ± 0.3 63.5 ± 4.8
    N 70% 5.8 8.6 ± 0.2 △ 47.5 ± 3.5
    - COLLAPSE
    August 2020
  • Article

    Effect of Organic Materials Amendment on Growth of Jujube (Zizyphus jujuba Mill.) and Soil Chemical Properties
    Heesoon Park, Kyeong Hee Lee, Ha Kyung Oh, Choong Woo Kim, Hyo-jung Kang, Sung-Hee Choi, and Hyunman Shin
    Jujube is a deciduous broad-leaved tree belonging to the buckthorn family(Rhamnaceae) and is widely cultivated in Southeast Asia and Southeast Europe ... + READ MORE
    Jujube is a deciduous broad-leaved tree belonging to the buckthorn family(Rhamnaceae) and is widely cultivated in Southeast Asia and Southeast Europe, including Korea and China and mainly consumed medicinal herbs or dried jujube. In recent years, consumption of fresh fruits has increased, and organic orchard has also increased. The purpose of this study was to investigate soil chemical changes and growth characteristics of jujube when replacing the total amount of nitrogen fertilizer with organic matter in rain shelter house. In March 2017, after soil testing, bark, animal compost, rice bran, oil cake and chemical fertilizers (NPK) were treated based on nitrogen content. After treatment of organic materials, by March 2020, the pH increased and organic matter, phosphoric acid and cation content in soil increased. After harvest of jujube, the yield of compost treatment was the highest and the NPK treatment was the lowest. The length, hardness and weight of fruit were greater in the NPK treatment, but the diameter and sugar content were not significantly different from the organic material treatments except rice bran. Therefore, when the cultivation of the jujube, nitrogen fertilizer was totally replaced with organic material, there was the effect of improving soil chemistry, such as an increase in the organic content of the jujube orchard and an increase in the yield of jujube but no clear effect on fruit quality. Yield of jujube by organic materials treatment. - COLLAPSE
    August 2020
  • Article

    Distribution of Nitrogen and Phosphorus in Arable and Forest Stand along the Boundary of Upstream Daechung Reservoir
    Il Whan Seo, Chul Soon Lim, Hyun Gyu Jung, Dong Sung Lee, Se Won Min, Kyo Suk Lee, and Doug Y. Chung
    This investigation was conducted to provide the control methods of N and P by observing the distribution of nitrogen and phosphorus in ... + READ MORE
    This investigation was conducted to provide the control methods of N and P by observing the distribution of nitrogen and phosphorus in arable and forest stands along the boundary of upstream Daechung Reservoir in which water quality properties caused by N and P from land uses was not extensively studied. To do this, we selected three different soil zone such as arable (paddy and upland), orchard, and forest stands including pine and larch of which inputs of N and P have been known to be different due to their foliage properties. Soil samples were collected from surface and subsurface to measure soil physical and chemical properties. The results showed that the soil textures of investigation sites are loamy sand and sandy loam and the stone ratio of both forest stand are approximately 38.7%. The organic matter content in both forest stands was above 5.6% while that of the paddy and upland are less than 3%. Soil pHs are strongly acidic except for orchard of which it is above 5.7 but less than 6.64. However, pHs of all the sites slightly increased from May to October. The amount of NO3- and NH4+ as water soluble phase is less than that of exchangeable phase in paddy while that of NO3- and NH4+ as exchangeable phase is greater than that of water soluble phase in upland and the forest stands of pine and larch. For the proportions of phosphorus remained as water soluble- and exchangeable phase depending on the total P, the proportion of water soluble in paddy and pine stand was greater than 10% while those of exchangeable P are less than 10% in upland, orchard, and larch stands. From these results based on the amount and the proportion of N and P in soil, we could assume that N and P from the both pine and larch stands may contribute the deterioration of water quality of Daechung Reservoir. Comparison of chemical properties for different land uses in the investigation sites of Daechung reservoir. Changes of T-N and ratio of A/B in top 20cm soil for various land uses along Daechung reservoir from May to October of 2019. - COLLAPSE
    August 2020
  • Article

    Phosphate Adsorption Characteristics of Activated Palm Biochar in Aqueous Solution
    Hui Seon Kim, Sangwon Park, Seok-In Yun, Hoon Choi, and JoungDu Shin
    Objective of this study was to investigate PO4-P adsorption characteristics of activated palm biochar with application of Langmuir isotherm. For ... + READ MORE
    Objective of this study was to investigate PO4-P adsorption characteristics of activated palm biochar with application of Langmuir isotherm. For the adsorption experiment of PO4-P to activated palm biochar, the loading amount of activated palm biochar varied from 0.4 to 6 g L-1 with 30 mg L-1 of PO4-P solution. The maximum adsorption amount and removal rates of PO4-P were 0.57 mg g-1 and 56.6%, respectively. The sorption of PO4-P of activated palm biochar was fitted well by a Langmuir model. For application of Langmuir isotherm, it appeared that the maximum adsorption amount of PO4-P and binding strength constant were estimated to be 9.36 mg g-1 and 0.005 L mg-1, respectively. Therefore, activated palm biochar can be used to control the release of PO4-P from supplemented biochar pellet fertilizer. Langmuir isotherm plots of PO4-P by different mass of activated palm biochar. The values were average of three replications. - COLLAPSE
    August 2020
  • Article

    Effects of Precipitation on Soil Water and Evapotranspiration in Differently-textured Paddy Soils during Non-cultivated Period: A Weighable Lysimeter Study
    Dong-Jin Kim, Jung-Hun Ok, Seung-Oh Hur, and Seon-Ah Hwang
    This study was performed to investigate the changes in evapotranspiration, soil temperature, and soil water in different paddy soils during the non-cultivated ... + READ MORE
    This study was performed to investigate the changes in evapotranspiration, soil temperature, and soil water in different paddy soils during the non-cultivated period (from January 1 to April 12 in 2017) using weighable lysimeters. The relationships between air temperature and soil temperature and between precipitation parameters and change content of soil water were also investigated. The evapotranspiration increased with increasing air temperature. The total amount of evapotranspiration in the study period was in the order of CL-L (coarse loamy-loam) > CL-SL (coarse loamy-sandy loam) > FC-SiCL (fine clayey-silty clay loam). All three soil types of FC-SiCL, CL-L, and CL-SL had a similar tendency to change in soil temperature. The soil temperature at a 0.1 m depth responded most sensitively to changes in air temperature. The air temperature was showed to have high significantly positive correlations with soil temperature at five depths (0.1 m, 0.3 m, 0.55 m, 0.85 m, and 1.25 m) in the three soils (p < 0.01). Especially the correlation coefficient between soil temperature of 0.1 m depth and the air temperature was higher than 0.9. The soil water content responded most sensitively to precipitation at 0.1 m depth in all three soils. The change content of soil water differed according to the soil water content before precipitation. Precipitation and change content of soil water at depths of 0.1 m and 0.3 m was highly positively (p < 0.01) correlated in all three soils. Change in the content of soil water at a 0.1 m depth was positively (p < 0.05) related to precipitation intensity and precipitation kinetic energy. Soil texture, soil water content, and precipitation conditions need to be considered to establish the irrigation management plan necessary before transplanting. The values of correlation coefficient (r) between the precipitation parameters and change content of soil water (<i>△</i>SW).
    Parameter Change content of soil water (△SW)
    0.1 m depth 0.3 m depth
    FC-SiCL (n = 16) CL-L (n = 16) CL-SL (n = 16) FC-SiCL (n = 16) CL-L (n = 16) CL-SL (n = 16)
    PR 0.745** 0.784** 0.751** 0.702** 0.691** 0.733**
    PI 0.617* 0.513* 0.534* 0.464 0.385 0.455
    PKE 0.621* 0.521* 0.542* 0.468 0.391 0.460
    PR, amount of precipitation; PI, precipitation intensity; PKE, precipitation kinetic energy. △SW, change content of soil water = soil water content at the end of precipitation (SWE) - soil water content before precipitation (SWB). FC-SiCL, fine clayey and silty clay loam; CL-L, coarse loamy and loam; CL-SL, coarse loamy and sandy loam. Correlation coefficient (r) was determined by Pearson correlation analysis to evaluate the relationship between parameters. Results were evaluated with 95% and 99% confidence intervals; *, significant at p < 0.05, and **, significant at p < 0.01 level.
    - COLLAPSE
    August 2020
  • Article

    Growth and Phosphorous Absorption Rate of Red Pepper as Affected by Top Dressing Applications of Phosphorus Fertilizer in Different Cropping System
    Hyo-Jung Choi, Byung-Koo Ahn, Do-Young Ko, Hyo-Jin Kim, Hyong-Gwon Chon, Ye-Jin Lee, and Seok-In Yun
    An experiment was conducted to study the effect of top dressing application of Phosphorus (P) fertilizer on the growth and P absorption ... + READ MORE
    An experiment was conducted to study the effect of top dressing application of Phosphorus (P) fertilizer on the growth and P absorption rate of red pepper in different cropping systems of the upland. P fertilizer was applied with no treatment as control (CON), basal dressing application (BDA), 2 times-split of top dressing applications (2-TDA) and 3 times-split of top dressing applications (3-TDA). Red peppers were grown for 110 days and soil characteristics and crop growth were investigated every 20 days. Dry matter yield of red pepper significantly increased at the 2-TDA and 3-TDA but decreased at the CON and BDA due probably to the decrease or increase in available P. In particular, at 3-TDA there was an increase in growth and P absorption rate of red pepper. The fruit dry matter weight of red pepper receiving 3-TDA was 961.7 kg 10a-1, which was significantly higher than those receiving CON and BDA in Rainproof cultivation. In case of the Rainproof cultivation, we found out both P fertilization use effect and top dressing applications effect because there was low available P content of soil used in the experiment in comparison other cultivation type. Therefore, considering the dual goal of optimum crop growth and maximum P distribution instead of immobilization with soil, this study suggests that a testing of a site-specific proper application method of P including top dressing applications is prerequisite to achieving optimum agricultural productivity while minimizing nutrition quality misuse. Uptake of P by red pepper plants after 110 days of cultivation.
    Cultivation type Treatment P uptake
    110DAT
    (kg 10a-1)
    Protected cultivation CON 1.19ab
    BDA 1.01b
    2-TDA 1.14ab
    3-TDA 1.51a
    Rainproof cultivation CON 0.82b
    BDA 1.18b
    2-TDA 1.36b
    3-TDA 1.91a
    Open field cultivation CON 0.77b
    BDA 1.08a
    2-TDA 0.60bc
    3-TDA 0.55c
    110DAT means day after red pepper plants cultivation CON: no fertilization as control, BDA: aplication with P at 1.3 kg 10a-1, 2-TDA: aplication with P at 0.65, 0.33, 0.33 kg 10a-1, 3-TDA: aplication with P at 0.65, 0.22, 0.22, 0.22 kg 10a-1 in Protected cultivation CON: no fertilization as control, BDA: aplication with P at 3.7 kg 10a-1, 2-TDA: aplication with P at 1.85, 0.93, 0.93 kg 10a-1, 3-TDA: aplication with P at 1.85, 0.62, 0.62, 0.62 kg 10a-1 in Rainproof cultivation CON: no fertilization as control, BDA: aplication with P at 3.8 kg 10a-1, 2-TDA: aplication with P at 1.9, 0.95, 0.95 kg 10a-1, 3-TDA: aplication with P at 1.9, 0.63, 0.63, 0.63 kg 10a-1 in Open field cultivation Mean values(n=3), with different lowercase letters indicating significant difference at p=0.05 by Duncan's multiple range test.
    - COLLAPSE
    August 2020
  • Article

    Estimation of Rice Leaf Nitrogen Content and Yield using UAV Image
    Kyung­Do Lee, Chan-Won Park, Ho-yong Ahn, Suk-young Hong, Su-Yong Jang, Sang­Il Na, and Kyu-Ho So
    Unmanned Aerial Vehicle (UAV)s have a high resolution of around 10 cm and can acquire images with lower cost when we ... + READ MORE
    Unmanned Aerial Vehicle (UAV)s have a high resolution of around 10 cm and can acquire images with lower cost when we want. The purpose of this study was to estimate the rice leaf nitrogen content and grain yield using UAV image. We collected the time series UAV aerial images at the paddy fields and the data were compared with the rice leaf nitrogen contents and rice yield in the experimental sites. Correlation coefficient (R) between the vegetation indices (NDVI, GNDVI, RVI, GRVI) and rice leaf nitrogen contents were ranged from 0.8 to 0.9 from mid-July to late July. Correlation coefficient between the vegetation indices (NDVI, GNDVI, RVI, GRVI) and rice grain yield were more than 0.9 from mid-July to early August. Using these results, we were able to make the distribution map of the rice leaf nitrogen and yield. In the future, it will be necessary to study to recommend supplemental fertilization to ensure rice yield using UAV images information. Distribution map of rice leaf nitrogen contents using UAV imagery.( N ferilizer level (kg/ha) : Site #1 0, Site #2 135, Site #3 158, Site #4 181, Site #5 204) - COLLAPSE
    August 2020
  • Article

    Estimation of Rice Cultivation Area by Threshold Method using Sentinel-1 Imagery in South Korea
    Kyung­Do Lee, Suk-Young Hong, Sook-Gyeong Kim, Chan-Won Park, Ho-Yong Ahn, Sang­Il Na, and Kyu-Ho So
    This study was carried out to classify country-wide areas of paddy rice cultivation using sentinel-1 SAR (synthetic aperture radar) imagery. Rice production ... + READ MORE
    This study was carried out to classify country-wide areas of paddy rice cultivation using sentinel-1 SAR (synthetic aperture radar) imagery. Rice production with adequate level of area is important for decision making of rice supply and demand policy. It is essential to grasp rice cultivation areas in advance for estimating rice production of the year. Time-series Sentinel-1A and 1B images acquired from early May to early July were processed to convert into sigma naught (dB) images using SNAP (SeNtinel application platform) toolbox provided by European Space Agency. Farm map and parcel map, which are spatial data of vector polygon, were used to stratify paddy field population for classifying rice paddy cultivation. To distinguish paddy rice from other crops grown in the paddy fields, threshold levels were determined for each image based on crop calendar and backscattering coefficient range of paddy rice and other crops, and applied for the images to make theme maps with “1” for rice and “0” for other crops. Theme map layers were stacked to make one image and the each threshold value was applied to the theme map for rice classification. The classified areas of rice cultivation in 2020 under the stratification of three different paddy field population, 1) whole farm map, 2) farm map with paddy and plastic film house, 3) parcel map edited by LX, were 716,683 ha, 621,778 ha, and 641,679 ha, respectively. Reference data with spatial information need to be developed using farmhouse management and farmland boundary information. Image classification methods need to be attempted for further studies. Maps for paddy rice cultivation areas classified from Sentinel-1 imagery using different rice paddy - COLLAPSE
    August 2020
  • Article

    Metabolic Profiling Reveals Altered Carbon and Nitrogen Metabolism in Cabbage (Brassica Rapa L.) Plants by the Deficiency of Micronutrients
    Jwakyung Sung
    Micronutrients, essential elements for optimal growth and development of most crop plants, are also directly or indirectly employed in biochemical processes. Despite ... + READ MORE
    Micronutrients, essential elements for optimal growth and development of most crop plants, are also directly or indirectly employed in biochemical processes. Despite an importance, an information about micronutrient- affected metabolic changes is lacked compared to those of macronutrient. Here, an author describes several findings of metabolic changes from the shoots and roots of cabbage plants grown under 1/10 strength of optimal growth condition (Hoagland nutrient solution). The deficient conditions of all micronutrients (Cu, Zn, Fe, Mn, B, and Mo) revealed a majority of primary metabolites was decreased in both tissues, whereas β-alanine was obviously enhanced. Moreover, micronutrient deficiency led to a significant reduction of secondary metabolism-intermediates, ferulic and sinapic acids. From the point of view of amino acid metabolism, Zn- and B-deficient conditions influenced similarly. Therefore, the findings from the present study provide new insights to better understand micronutrient-specific metabolic changes in cabbage plants. Global metabolic changes in micronutrient deficiency-affected cabbage plants. - COLLAPSE
    August 2020
  • Short Communication

    Effects on Growth Characteristics of Chinese Cabbage to Application of Formulated Granular Fertilizer Contained Activated Biochar
    In-Ho Jung, Hong-Sik Na, Minsoo Kim, Hong-Shik Nam, and JoungDu Shin
    This study was conducted to develop an eco-friendly slow-release fertilizer by utilizing activated biochar through black carbonization of rice hull biochar and ... + READ MORE
    This study was conducted to develop an eco-friendly slow-release fertilizer by utilizing activated biochar through black carbonization of rice hull biochar and activated palm biochar. To manufacturing these fertilizers, the raw materials were ground into powder form, mixed with the binder, granulated, and then screened and dried. The best six types were selected by considering the hardness and coupling degree with activated biochar and binder. The nutrient contents of the granular fertilizer contained within the activated biochar were 30-0-13 (N-P2O5-K2O, %). Results did not show a significant effect on cabbage’s leaf color, length, and width among the different treatments except for the control. However, it showed that the highest yield among the treatments was 3.5 kg plant-1 in the treatment of 5% of rice hull activated biochar. In this treatment, the yield was increased by 20% relative to that of the control. Therefore, it was decided that the optimum mixing ratio was 5% of activated rice hull biochar. The best six types were selected for considering the hardness and coupling degree with activated biochar and binder. - COLLAPSE
    August 2020
  • Short Communication

    Distribution of Water-Soluble Nutrients and Physico-Chemical Properties of Upland and Orchard Field Soils in Jeonbuk Province
    Byung-Koo Ahn, Do-Young Ko, Hyo-Jung Choi, and Hyong-Gwon Chon
    This study was carried out to investigate the physico-chemical properties and water-soluble nutrients content in 160 samples of upland and 120 samples ... + READ MORE
    This study was carried out to investigate the physico-chemical properties and water-soluble nutrients content in 160 samples of upland and 120 samples of orchard in Jeonbuk province. The mean depths of horizon A of the upland and orchard soils were 24.2 ± 4.2 cm and 27.8 ± 5.9 cm, respectively. Soil pH, EC, and organic matter contents were within the optimal range for upland and orchard soils, but available phosphate and exchangeable K, Ca, and Mg were higher than the optimal range; e.g., available phosphate concentrations were higher than the optimal range by 52.8% for the upland and 61.7% for the orchard. Water-soluble Mg2+, Cl-, and SO42- were higher in upland than orchard soils, and K+, Ca2+, NO3-, and PO43- showed an opposite pattern. These results provide fundamental information of the properties of upland and orchard soils in Jeonbuk province for better management of soil fertility. Correlation coefficient between water-soluble nutrients and soil chemical properties of uplands in Jeonbuk province.
    Chemical property Water-soluble nutrients
    K+ Ca2+ Mg2+ Cl- NO3- PO43- SO42-
    pH 0.020 0.413** 0.332** -0.012 -0.173* 0.108 -0.269**
    EC 0.633** 0.086 0.175* 0.694** 0.831** 0.016 0.577**
    OM 0.554** 0.313** 0.041 0.211** 0.335** 0.291** 0.230**
    Avail. P2O5 0.516** 0.228** 0.048 0.296** 0.393** 0.281** 0.163*
    Exch. K 0.893** 0.154* 0.194** 0.684** 0.614** 0.149* 0.472**
    Exch. Ca 0.455** 0.100 0.150* 0.548** 0.897** 0.018 0.590**
    Exch. Mg 0.498** 0.048 0.256** 0.562** 0.836** -0.013 0.545**
    A significant values reported as **p ≤ 0.01, *p ≤ 0.05.
    - COLLAPSE
    August 2020
  • Short Communication

    Effects of Different Application Rates of Organic Compound Fertilizer on Young Squash Growth and Soil Chemical Properties under Plastic Film House
    Myung Sook Kim, Seong Jin Park, Sung Hyun Kim, Hyun Young Hwang, Jae Hong Shim, and Yun Hae Lee
    To determine the replacement ratio of organic compound (OC) for basal application of inorganic fertilizers, the effects of different rate of OC ... + READ MORE
    To determine the replacement ratio of organic compound (OC) for basal application of inorganic fertilizers, the effects of different rate of OC on young squash (Cucurbita moschata) plant growth and soil chemical properties of plastic film house were investigated. The OC were applied at 50% (OC50+N50), 100% (OC100), and 150% (OC150) as the basal amount of inorganic nitrogen fertilizer recommended by soil fertility test, and the treatment were compared with inorganic NPK and PK treatment. The yield of young squash in OC150 treatment was similar to NPK treatment and higher than PK. In OC50+N50, OC100, and OC150 treatments, nitrate concentration and electrical conductivity (EC) were similar to NPK treatment. Relative nitrogen use efficiency of young squash ranged 17~37%. These results suggest that OC application as the basal dressing at the 150% level could be best rate to minimize nutrient accumulation of soil and to ensure the yield of young squash. Further study is required to evaluate effect of long-term application of OC on soil sustainability and young squash productivity. Changes of young squash yield according to replacement ratio of basal amount of nitrogen fertilizer with organic compound (OC) fertilizer. N, P, K, and OC mean nitrogen, phosphate, potash fertilizer, and organic compound, respectively.
    Treatment Fresh fruit weight Relative yield index
    kg/10a %
    PK 8,607b 96.0
    NPK 8,960ab 100.0
    OC50+N50 8,980ab 100.2
    OC100 9,013ab 100.7
    OC150 9,350a 104.5
    DMRT (p < 0.05). Relative yield of other treatments to NPK treatment.
    - COLLAPSE
    August 2020