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Original research article
- Effects of plowing depth on crops (watermelon, muskmelon, and squash) yield and soil chemical properties under plastic film house
- Myung-sook Kim, Tae-Gu Lee, Eun-jin Lee, Ha-il Jung, Seung-Gyu Lee
- Soil plowing depth is very important in improving soil quality and promoting of crop production system. The relationship between soil plowing depth …
- Soil plowing depth is very important in improving soil quality and promoting of crop production system. The relationship between soil plowing depth and soil chemical properties and crop yield was analyzed. Soils were sampled from 20 watermelons, 19 muskmelons, and 22 squash farms of plastic film house. The results showed that the average soil plowing depth of watermelon, melon, and squash cultivated in the plastic film house were 22 cm, 21 cm, and 27 cm, respectively. when the soil depth of watermelon and squash was deepened to 31 cm (26 - 39 cm), the levels of nitrate ion (NO3-), electrical conductivity (EC), and exchange cations (Ex. cations) decreased by 2 - 42% compared to 18 cm (14 - 24 cm). The concentration of NO3-, EC, and Ex. Potassium (Ex. K) of muskmelon cultivation with soil depth of 28 cm (26 - 36 cm) tended to decrease by 5 - 39% compared to 17 cm (14 - 22 cm). The yield of watermelon, muskmelon, and squash were increased by 6 - 22% when the soil plowing depth was 39 cm compared to 25 cm. The contribution of plowing depth to yield of 3 crops was highly significant at 13.1 - 28.2%. Therefore, deep tillage is necessary to improve soil health and increase yield of watermelon, muskmelon, and squash under plastic film house. Contribution of soil environmental factors affecting yield of watermelon, muskmelon, and squash in farm field of plastic film house. Variable Watermelon Muskmelon Squash Squared partial correlation coefficient Relative contribution (%) Squared partial correlation coefficient Relative contribution (%) Squared partial correlation coefficient Relative contribution (%) NO3- 0.04 0.8 0.15 9.8 0.01 2.8 PO43- 0.12 2.3 0.11 7.1 0.01 2.6 K+ 0.16 3.2 0.02 1.4 0.08 14.6 pH 0.35 6.9 0.36 23.3 0.03 6.4 EC 0.51 10.0 0.00 0.1 0.02 3.7 OM 0.03 0.6 0.12 7.9 0.02 4.6 Av.P2O5 0.22 4.4 0.01 0.7 0.03 4.8 Ex.K 0.01 0.1 0.08 5.2 0.06 11.0 Ex.Ca 0.20 4.0 0.15 9.9 0.06 10.8 Ex.Mg 0.50 9.9 0.00 0.3 0.03 6.1 Plowing depth 0.66 13.1 0.38 24.5 0.15 28.2 CEC 0.42 8.2 0.00 0.2 0.01 1.3 Clay 0.16 3.1 0.15 9.6 0.02 3.2 Sum 3.37 100 1.55 100 0.52 100 - COLLAPSE
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Original research article
- Effects of soil chemical properties on inorganic and organic carbon contents in organic, calcareous, and reclaimed-tidal soils
- A-Rin Kim, Cho-Rong Lee, Hyun-Hwoi Ku
- Soil carbon (T-C) consists of approximately 60% of soil organic carbon (SOC) and 40% of soil inorganic carbon (SIC), but many researches …
- Soil carbon (T-C) consists of approximately 60% of soil organic carbon (SOC) and 40% of soil inorganic carbon (SIC), but many researches has focused mainly on SOC. This study aimed to evaluate the effects of soil chemical properties on SOC and SIC contents in three different agricultural soils. The soils in an organic farming, calcareous, and reclaimed tidal soil were sampled for analysis of T-C, SOC, SIC and other chemical parameters such as soil pH, total nitrogen (T-N), 4-cations, and CEC. We applied the correlation analysis to identify the chemical parameters affecting the SOC and SIC contents in the organic farming, calcareous, and reclaimed tidal soils. Organic farming soil showed the highest SOC content (1.98%), followed by calcareous (1.46%) and reclaimed tidal soils (0.24%) although calcareous soil had the highest T-C content (2.87%), followed by organic farming (2.09%) and reclaimed tidal soil (0.81%), respectively. These were attributed to the difference of SIC contents between the soils since the organic farming, calcareous, and reclaimed tidal soils showed 0.21%, 1.41%, and 0.57% of SIC contents, respectively. The proportions of SOC and SIC contents were 93% and 7% in organic farming soil, 57% and 43% in calcareous soil, and 30% and 70% in reclaimed tidal soil, respectively. The different proportions of SOC and SIC between the soils were influenced by the chemical parameters (Ca2+ and Mg2+ and soil pH) since these parameters were significantly correlated with SIC contents. Proportion rate of soil organic and inorganic carbon contents in organic farming (OF), calcareous soil (CS), and reclaimed tidal soil (RS). - COLLAPSE
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Original research article
- Isolation and characterization of plant growth-promoting rhizobacteria from soil
- Soyoun Lee, Hyeonji Kim, Sungwoo Kim, Kyungjin Kwak, Sugju Ko
- To isolate and select useful microbial resources for agricultural environments, 26 microbial species with diverse colors and morphologies were isolated from soil. …
- To isolate and select useful microbial resources for agricultural environments, 26 microbial species with diverse colors and morphologies were isolated from soil. Antifungal tests against three plant pathogens revealed that seven strains, including CH22-3 (identified as Burkholderia ambifaria) and AB22-1 (Bacillus amyloliquefaciens), exhibited antifungal activity, with CH22-3 and AB22-1 showing the strongest effects. Evaluation of plant growth-promoting traits such as nitrogen fixation, phosphate solubilization, IAA, and siderophore production showed that all seven strains demonstrated nitrogen fixation, with CH22-3 achieving the highest phosphate solubilization (135.6%), and AB22-1 exhibiting the highest levels of IAA production (8.0 µg ml-1) and siderophore production (5.7 mm halo zone). Lettuce treated with AB22-1 at concentrations of 1×105 to 1×107 cfu/ml showed increases in shoot and root biomass by 26 - 31% and 18 - 20%, respectively, compared to the control group, indicating AB22-1 strain potential as a biofertilizer. These results underscore the need for further comparative studies with chemical fertilizers. Growth-promoting effect of Bacillus amyloliquefaciens AB22-1 isolated from soil on lettuce. Treatment Leaf length (cm) Leaf width (cm) Number of leaves (per plant) Fresh weight (per 10 plant) Chlorophll (SPAD) Shoot Root AB22-1 culture 105 Seedling 21.8 bcd 17.0 bc 12.8 ab 130.3 c 20.0 a 32.0 a Transplanting 22.4 abcd 18.0 ab 12.3 ab 146.8 abc 20.0 a 31.5 a Post-transplanting 23.3 ab 18.4 ab 13.5 ab 162.0 a 20.9 a 31.1 a 106 Seedling 21.9 bcd 18.1 ab 12.7 ab 137.3 bc 20.1 a 33.2 a Transplanting 22.1 abcd 17.9 ab 13.7 a 147.5 abc 21.4 a 30.6 a Post-transplanting 21.0 d 17.9 ab 12.5 ab 128.6 c 20.1 a 33.6 a 107 Seedling 23.6 ab 18.0 ab 13.8 a 168.4 a 20.5 a 31.7 a Transplanting 23.8 a 18.7 a 14.0 a 159.0 ab 20.0 a 30.6 a Post-transplanting 23.3 ab 17.3 abc 13.0 ab 146.3 abc 18.4 a 30.8 a Media (LB broth) 22.9 abc 17.8 ab 11.5 b 128.6 c 18.2 a 28.8 a control 21.3 cd 16.0 c 12.0 ab 128.5 c 17.4 a 29.8 a - COLLAPSE
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Original research article
- Early growth response of tomatoes to soil EC levels using on-site soil diagnosis
- Tae-Gu Lee, Seung-Gyu Lee, Eun-Jin Lee Ha-il Jung, Myung-sook Kim
- Soil electrical conductivity (EC) is widely used as an indirect indicator of salt accumulation. On-site diagnosis is a practical method for assessing …
- Soil electrical conductivity (EC) is widely used as an indirect indicator of salt accumulation. On-site diagnosis is a practical method for assessing soil conditions in real-time during crop cultivation. However, greenhouse soils often exhibit EC levels exceeding the standard osmotic stress threshold of 2 dS m-1 (On-site diagnosis standard), leading to frequent high-stress diagnoses that do not account for crop-specific salt tolerance. This study aimed to refine on-site diagnostic accuracy by evaluating early growth responses of tomatoes, a moderately salt-tolerant crop, across various EC levels. A 35-day cultivation experiment was conducted using soil with 4% organic matter, representative of greenhouse conditions. On-site diagnosis soil EC was adjusted from 1 to 20 dS m-1 in seven increments using KNO3. Increased KNO3 levels reduced soil-soluble phosphate, leading to a decrease in plant phosphorus content above EC 15 dS m-1. Growth analysis revealed that plant height, fresh weight, and dry weight significantly declined when EC exceeded 5 dS m-1, with growth at EC levels above 15 dS m-1 dropping to less than 10% of the 2.5 dS m-1 treatment group. Based on soil and plant analyses, the optimal EC threshold for early tomato growth in soils with 43 g kg-1 organic matter was determined to be below 5 dS m-1. Therefore, in soils with EC exceeding 5 dS m-1, young tomato cultivation should be avoided unless appropriate salt management strategies are implemented. Inhibition of early tomato growth with increasing on-site diagnosis soil EC. - COLLAPSE
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Original research article
- Effect of organic materials on phosphorus solubilization in phosphate-accumulated soils: an incubation study
- Yu-Bin Hwang, Hyun-Young Hwang, Nan-Hee An, Sang-Min Lee, Cho-Rong Lee
- Phosphorus accumulation in soil leads to soil quality degradation and yield reduction. Therefore, effective phosphorus management is essential for maintaining a sustainable …
- Phosphorus accumulation in soil leads to soil quality degradation and yield reduction. Therefore, effective phosphorus management is essential for maintaining a sustainable agroecosystem and ensuring crop productivity. This study aimed to evaluate the effects of various organic materials on phosphate availability in phosphorus-accumulated soil, identify suitable organic materials, and determine optimal application rates for solubilizing accumulated phosphate. The materials tested including organic acid, peat moss, zeolite, sulfur, hairy vetch, rice straw, wheat bran, expeller cake, and DTPA (a chelating agent). The treatment rates were applied on a weight/weight (w/w) basis, with DTPA and distilled water serving as the controls. Soil pH, available phosphate, water-soluble phosphate, and phosphatase activity were analyzed at 0, 7, 14, and 30 days through incubation experiments. The results indicated that sulfur, expeller cake, DTPA and hairy vetch effectively reduced soil pH. Available phosphate increased by 25% and 17% compared to the control with sulfur and expeller cake, respectively. Water-soluble phosphate increased by 21% to 75% compared to the control with sulfur, rice straw (1%), zeolite, expeller cake (2%), and wheat bran (2%). Acid phosphatase activity was enhanced by organic acid (0.5%, 1%), zeolite (1%), rice straw (2%), wheat bran, and hairy vetch (0.5%, 1%, 2%). This study demonstrated that organic materials have phosphate solubilization effects comparable to DTPA. Changes in (A) water soluble P2O5 and (B) acid phosphatase in soils with accumulated phosphate through the application of organic materials. - COLLAPSE
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Original research article
- Water quality of inland lakes affects salinity and sodicity of coastal paddy soils in southwestern Korea
- Seo-Woo Park, Nuri Baek, Se-In Lee, Eun-Seo Shin, Jiyu Lee, Kwang-Seung Lee, Bang-Hun Kang, Kyo-Suk Lee, Han-Yong Kim, Woo-Jung Choi
- Soil salinity and sodicity of coastal paddy are critical factors affecting rice growth. This study investigated the temporal changes in salinity and …
- Soil salinity and sodicity of coastal paddy are critical factors affecting rice growth. This study investigated the temporal changes in salinity and sodicity of coastal paddy soils on reclaimed tideland (RTL) in southwestern Korea between 2018 and 2023. Soil samples were collected from a total of 139 paddy fields in five RTL districts and inland lake water samples were also collected. The soil and water samples were analyzed for salinity and sodicity parameters including the electrical conductivity (EC) and sodium adsorption ratio (SAR). Although literature suggested that coastal paddy soils tend to be gradually desalinized with rice cultivation after reclamation, in this study, both salinity and sodicity of the coastal paddy soils tended to increase by 0.4 - 7.7 dS m-1 for EC and by 6.3 - 31.7 for SAR between 2018 and 2023. These changes in EC and SAR were not correlated with sand content, which affects salt movement in soils. Rather than, EC and SAR of coastal paddy soils on average across the paddy fields for each RTL district in each year were closely correlated with those of inland lake water, which is the source of irrigation for paddy fields. These results imply that salinity and sodicity of the coastal paddy soils are primarily linked to the irrigation water quality, which is also affected by inter-annual variations in the precipitation. Correlations of electrical conductivity (EC) and sodium adsorption ratio (SAR) between inland lake water and paddy soils of five reclaimed tideland (RTL) districts across 2018 – 2023. - COLLAPSE
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Original research article
- Methane emission from paddy soil with different transplanting time of rice (Oryza sativa L.) in Gyeongsang region
- Sung Un Kim, Hyun Ho Lee, Dong Hyun Kim, Geon Hyeong Lee, Chang Oh Hong
- Methane (CH4) emissions from paddy soil significantly contribute to global greenhouse gas emissions, with transplanting time being a significant factor …
- Methane (CH4) emissions from paddy soil significantly contribute to global greenhouse gas emissions, with transplanting time being a significant factor influencing CH4 flux. This study evaluated the effects of four different transplanting times with 15 days intervals (1st 2022/05/10, 2nd 2022/05/25, 3rd 2022/06/10, and 4th 2022/06/25) on CH4 emissions in a paddy soil in the Gyeongsang region of South Korea. Using a closed chamber method, CH4 flux was measured weekly throughout the growing season of rice. The results showed that CH₄ emissions increased during the early growing stage, peaked, and subsequently decreased. Cumulative CH4 emissions were highest for the 1st transplanting time (2022/05/10) and decreased significantly with later transplanting times, reaching a 65% reduction for the 4th transplanting time (2022/06/25). The optimal transplanting time when CH4 emissions were minimized in Gyeongsang region, South Korea was on June 25. Correlation analysis indicated a significant correlation between root biomass and cumulative CH₄ emissions. This implied that root biomass of rice was related to CH4 transport and production. The results of this study clearly demonstrated that modifying transplanting time of rice could be an effective strategy for reducing CH4 emissions from paddy soil. Cumulative CH4 emissions for different transplanting times. - COLLAPSE
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Original research article
- Co-application of urea and ammonium sulfate enhances cabbage productivity by increasing nitrogen use efficiency in a pot experiment
- Yeomyeong Lee, Sang Yoon Kim
- Nitrogen (N) is an essential element for crop growth, thus appropriate N fertilization strategy is required to enhance productivity while minimizing the …
- Nitrogen (N) is an essential element for crop growth, thus appropriate N fertilization strategy is required to enhance productivity while minimizing the losses from the arable soils. Urea (U) and ammonium sulfate (AS) can provide available soil N at different rates during cultivation due to their differential solubility, affecting plant uptake and soil properties. Co-application of U and AS may improve the efficiency of individual fertilizers, but its effects on crop yield and the related environmental properties have not been systematically studied. This study evaluated the impact of co-application of U and AS on Chinese cabbage (Brassica rapa subsp. pekinensis) productivity by investigating N use efficiency (NUE), growth characteristics, and soil properties in a pot experiment. The experiment included four treatments: three N fertilization regimes with an equivalent N rate under the recommended fertilization rate (U alone, AS alone, and Urea+AS co-application at a 1:1 ratio), and a control treatment without N fertilizer (PK treatment). Results showed that co-application significantly increased cabbage productivity, with yield improvements of 30 - 56% compared to single N fertilizer applications. Productivity enhancement was strongly correlated with increased N uptake, NUE, and inorganic N availability in soils at the harvesting. The findings indicate that co-application may provide a balanced N supply throughout the whole growth stages, possibly optimizing N utilization by the crop. However, this study has limitations as we were not able to monitor temporal changes in soil inorganic N during the whole plant growth, emphasizing the need for further research. Nevertheless, our study suggest that co-application can effectively enhance NUE, supply available N and improve soil properties, supporting sustainable N fertilization regimes in agriculture. Hypothetical diagram of soil Inorganic N dynamics and crop response under different N fertilization regimes. - COLLAPSE
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Short communication
- Chemical characteristics and nutrient management of rice cultivation soil in the Dominican Republic
- Jihye Cha, Da-Young Kim, Seong-Bin Kim, Francisco Jiménez, Ewddy Perez, Yeryeong Kim, Seoryeong Lee, Won-Il Kim
- Recent efforts to enhance sustainable agricultural practices and crop productivity emphasize the management of external inputs such as chemical fertilizers based on …
- Recent efforts to enhance sustainable agricultural practices and crop productivity emphasize the management of external inputs such as chemical fertilizers based on soil chemical properties. A major issue in Dominican agriculture is inadequate soil management, leading to soil degradation and low crop productivity. This study aimed to assess the characteristics of paddy soil, a staple crop in the Dominican Republic, for appropriate nutrient management. Soils were sampled from 28 rice farms in January 2024 and analyzed chemically according to soil analysis standard procedures at the IDIAF Central Center. The soil pH averaged 6.9 (5.4 - 7.9), indicating neutrality with some soils showing alkalinity. Electrical Conductivity was measured at 0.55 (0 - 1.32) dS m-1, indicating appropriate levels in most soils. Organic matter content averaged 56.4 g kg-1 (35.5 - 86.5 g kg-1), and available phosphorus content averaged 25.4 mg kg-1 (3.98 - 118.3 mg kg-1), indicating phosphorus deficiency in some soils. Exchangeable calcium content was high, averaging 20.5 cmolc kg-1 (6.7 - 32.5 cmolc kg-1), while exchangeable magnesium content averaged 0.64 cmolc kg-1 (0.16 - 0.92 cmolc kg-1) and exchangeable potassium content averaged 0.36 cmolc kg-1 (0.08 - 0.85 cmolc kg-1), both below optimal levels. Trace nutrients such as copper, manganese, iron, and zinc were found to be above optimal levels. Calcium saturation rate was high at 93.5%, while magnesium saturation was low at 3.2%, potentially promoting phosphate immobilization by calcium, raising concerns about phosphate deficiency in crops. In conclusion, soil acidity, phosphorus, calcium, and magnesium management is necessary for paddy soils in the Dominican Republic. Relative distribution percentage (%) of paddy soils with range of exchangeable Ca and Mg content in Dominican Republic. - COLLAPSE
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Short communication
- Regional differences in chemical and biological characteristics of organic upland soils in Chungbuk province
- Jiwon Do, SeongKyeom Kim, Sung-Hee Lee, Cho-Rong Lee, Jae-Ho Park, Ju-Hyoung Kim
- The chemical and biological properties of the soil are important factors affecting crop productivity and soil health. Therefore, main purpose of this …
- The chemical and biological properties of the soil are important factors affecting crop productivity and soil health. Therefore, main purpose of this study was to investigate the chemical and biological properties of soils managed organically for over five years in the Chungbuk region, as well as the correlations among these properties. As a result of the analysis, the soil in the northern region generally had higher pH (7.4) and soil organic matter (45.1 g kg-1) compared to other regions (p < 0.05). In addition, it was confirmed that calcium and magnesium tended to accumulate excessively as the soil organic matter increased. On the other hand, the overall enzyme activity and soil respiration tended to increase according to the soil organic matter. In particular, the accumulation of organic matter significantly promoted dehydrogenase (149.3 TPF μg g-1 24 h-1) and urease activities (210.0 NH4-N μg g-1 24 h-1), which are interpreted as the result of enhancing the microbial organic matter decomposition and nitrogen cycle process. These results suggest that while soil organic matter has a positive effect on soil microbial activity, excessive accumulation of cations can have a negative effect on crop growth and soil health, suggesting the importance of balanced organic matter management. This study provides important basic data for evaluating the soil health of organic farmland, and suggests the need for future research to elucidate the effects of these characteristics on agricultural productivity and environmental health. Pearson correlation coefficient of the chemical and biological properties of soils in the Chungbuk region. pH EC OM Av. P2O5 T-N Ex. Ca Ex. K Ex. Mg SR DHA GLU URE AP pH 1 EC -0.21* 1 OM 0.20 * 0.03 1 Av. P2O5 -0.01 0.14 0.09 1 T-N -0.01 0.13 0.46 ** 0.28 ** 1 Ex. Ca 0.47 ** -0.10 0.41 ** 0.05 0.10 1 Ex. K 0.04 0.09 0.12 0.45 ** 0.43 ** 0.06 1 Ex. Mg 0.33 ** -0.05 0.41 ** 0.28 ** 0.18 0.60 ** 0.27 ** 1 SR 0.37 ** -0.09 0.44 ** 0.03 0.29 ** 0.34 ** 0.16 0.27 ** 1 DHA 0.56 ** -0.16 0.32 ** 0.06 0.24 ** 0.23 * -0.01 0.33 ** 0.45 ** 1 GLU 0.34 ** 0.05 0.21 * 0.08 0.35 ** 0.27 ** 0.12 0.24 ** 0.29 ** 0.61 ** 1 URE 0.51 ** -0.12 0.35 ** 0.24 * 0.35 ** 0.30 ** 0.30 ** 0.37 ** 0.50 ** 0.67 ** 0.55 ** 1 AP -0.64 ** 0.30 ** -0.10 0.10 0.17 -0.30 ** 0.06 -0.26 ** -0.23 * -0.33 ** 0.01 -0.39 ** 1 - COLLAPSE
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Short communication
- Determination of optimal mixing ratio of organic fertilizer and biochar derived from agricultural waste to increase crop growth and soil carbon sequestration
- Sin-Sil Kim, Yu-Na Lee, Dong Won Lee, Jae-Hong Shim, Sang-Ho Jeon, Ahn-Sung Roh, Soon-Ik Kwon, Seong-Heon Kim
- Soil organic carbon (SOC) can be accumulated through various organic inputs such as organic fertilizers, compost, and biochar. While organic fertilizers are …
- Soil organic carbon (SOC) can be accumulated through various organic inputs such as organic fertilizers, compost, and biochar. While organic fertilizers are effective in supplying nutrients, they have limitations in stable carbon sequestration compared to biochar. Therefore, this study aimed to determine the optimal mixing ratio of organic fertilizer and biochar that can supply nutrients while ensuring sustained and stable carbon sequestration. The growth of lettuce, soil chemical properties, and soil carbon sequestration were evaluated through a pot experiment based on the mixing ratios of organic fertilizer and biochar derived from agricultural waste. The treatments in the pot experiment included no fertilizer (NF), inorganic fertilizer (IF), and biochar mixed organic fertilizer (BAOF), mixing ratios of organic fertilizer:biochar = 100:0, 90:10, 80:20, 70:30. The results showed that leaf length and width of lettuce increased by 1.70 - 1.84 and 1.58 - 1.78 times, respectively, in BAOF treatments compared to NF. The highest yield was observed in BAOF (100:0). The organic matter content increased with higher mixing ratio of biochar. SOC stock was observed in the following order: 11.93 (BAOF70:30) > 11.22 (BAOF80:20) > 10.35 (BAOF90:10) > 10.26 (BAOF100:0) t C ha-1. In conclusion, mixing biochar with organic fertilizers promoted lettuce growth and led to increased soil carbon sequestration. These results indicated that the optimal mixing ratio was determined to be BAOF70:30. Changes in soil characteristics after pot test under different treatments of fertilizer. Treatment pH (1:5) EC (dS m-1) SC stock (t C ha-1) Av. P2O5 (mg kg-1) Exch. cations (cmolc kg-1) K Ca Mg Na NF1 7.3 a 0.6 c 10.01 b 275 b 0.27 b 7.0 a 1.3 a 0.15 b IF2 7.3 a 0.6 bc 10.19 b 276 b 0.27 b 7.3 a 1.3 a 0.14 c BAOF3 100:0 7.3 a 0.7 bc 10.26 b 279 b 0.26 b 7.6 a 1.4 a 0.19 b 90:10 7.2 a 0.8 b 10.35 b 278 b 0.25 b 7.5 a 1.3 a 0.15 b 80:20 7.4 a 0.9 a 11.22 a 366 a 0.44 a 7.7 a 1.4 a 0.33 a 70:30 7.3 a 0.7 bc 11.93 a 285 b 0.26 b 7.4 a 1.4 a 0.16 b Optimal range‡ 6.5 - 7.0 ≤2 - 250 - 400 0.40 - 0.60 6.0 - 7.0 2.0 - 2.5 - 1NF, no fertilizer; 2IF, inorganic fertilizer; 3BAOF, biochar derived from agricultural waste mixed organic fertilizer. - COLLAPSE
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Short communication
- Effect of organic and conventional farming practices on the greenhouse gas emissions and stable organic carbon in rice-onion rotation cropping system
- Yeon-Ho Kim, Sang-Min Lee, Jung-Ah Jung, Da-In Kang, Nan-Hee An, Cho-Rong Lee, Hyun-Young Hwang
- This study aimed to evaluate the greenhouse gas (GHG) emission rates and the stable organic carbon content in organic and conventional systems …
- This study aimed to evaluate the greenhouse gas (GHG) emission rates and the stable organic carbon content in organic and conventional systems during rice-onion cropping season. Methane (CH4) and nitrous oxide (N2O) emissions rates were investigated using the closed chamber method. As a stable carbon, mineral- associated organic matter (MAOM) and humic substances were selected and determined through physical and chemical fraction methods. During the rice and onion growing seasons, the CH4 and N2O emissions patterns exhibited similar trends in both organic and conventional practices. However, the total greenhouse gas emissions in the organic was notably lower than conventional farm, and the impact of the rice season (70%) was much higher than onion. Furthermore, humic substances and MAOM were 14% and 13% higher, respectively, in the organic system compared to the conventional system (p < 0.05). This suggested that organic farming management could contribute to mitigating climate change by reducing GHG flux and increasing stable soil organic carbon. Stable soil organic carbon; (A) humic and fulvic acid and (B) mineral-associated organic carbon of organic and conventional rice-onion rotation fields. Symbol * indicates significance at p < 0.05. - COLLAPSE
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Review
- Biochar effects on methane emission from rice paddy differ with nitrogen fertilization, organic inputs, and water management
- Nuri Baek, Se-In Lee, Husna Israt Pia, Seo-Woo Park, Eun-Seo Shin, Jiyu Lee, Han-Yong Kim, Woo-Jung Choi
- The effects of biochar (BC) on methane (CH4) emission may vary with nitrogen (N) fertilization rate, organic inputs, and water …
- The effects of biochar (BC) on methane (CH4) emission may vary with nitrogen (N) fertilization rate, organic inputs, and water management. In this short review, we studied the changes in the direction and magnitude of CH4 emission by BC under these different conditions. Literature data indicated that co-application of BC with N fertilizer may increase or decrease CH4 emission depending on the N fertilization rates. Although the threshold N fertilization rate for the enhanced CH4 emission by BC is unclear, it was suggested that N fertilization may enhance BC-induced CH4 oxidation via the supply of N to methanotrophs. Although organic inputs stimulate CH4 emission, co-application of BC with organic inputs efficiently decreases CH4 emission by reducing C substrate availability for methanogens via sorption onto BC particles. The application of BC also enhances CH4 oxidation under water-saving irrigation to stimulate the methanotroph activity under aerobic conditions. Our study suggests that application of BC may be a measure to mitigate CH4 emission from paddy soils amended with organic inputs and it may further enhance CH4 oxidation under water-saving irrigation. The direction and mechanisms of the changed CH4 emission by biochar with N fertilization, organic inputs, and water-saving irrigation. - COLLAPSE
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Opinion
- Quantitative classification of ‘excessively drained’ and ‘somewhat excessively drained’ of Korean soils using soil properties
- Danbi Lee, Byeong Hwan Seo, SongRae Cho, WooRi Go, MinSan Im, Yeon Kyu Sonn
- The classification of soil drainage is broadly defined based on internal soil drainage and permeability, as well as relationships with soil color …
- The classification of soil drainage is broadly defined based on internal soil drainage and permeability, as well as relationships with soil color mottles, the location of mottles, groundwater level, soil texture, parent material, and topography. In Korea, soil drainage classes are defined as ‘somewhat excessively drained,’ ‘well drained,’ ‘moderately well drained,’ ‘somewhat poorly drained,’ and ‘poorly drained.’ However, the classification criteria for ‘excessively drained’ and ‘somewhat excessively drained’ in Korea are currently not quantified, making them ambiguous. Therefore, this study aims to classify soil series distributed in Korea into drainage classes such as ‘excessively drained’ and ‘somewhat excessively drained’, which currently lack clear classification criteria. The study follows the Soil Survey Manual and proposes quantified classification criteria based on soil characteristics. According to the Soil Survey Manual, ‘somewhat excessively drained’ is defined as ‘water is removed very rapidly or rapidly, consisting of coarse-textured soil with very high saturated hydraulic conductivity or very shallow effective soil depth.’ Quantitatively, this is classified as coarse-textured soil (Clay < 15%, Silt < 30%, and Sand ≥ 70%) with very high or high saturated hydraulic conductivity or very shallow effective soil depth (< 25 cm). Based on these criteria, forest soils in Korea were classified, and it was confirmed that some forest soils were misclassified. The proposed quantitative criteria for drainage classes are expected to be widely utilized by researchers for direct classification, moving away from traditional reliance on survey experts. These criteria are also expected to contribute to field farming guidance and the development of soil management strategies. Furthermore, correcting misclassified soils is essential to improve the accuracy of soil suitability ratings for crops. A quantitative criterion for soil drainage class classification. Class Criteria Excessively drained Coarse texture (Clay < 15%, Silt < 30%, and sand ≥ 70%), very high saturated hydraulic conductivity, very shallow Root-Restricting Depth (< 25cm) New criteria Somewhat excessively drained Coarse texture (Clay < 15%, Silt < 30%, and sand ≥ 70%), high saturated hydraulic conductivity, very shallow Root-Restricting Depth (< 25cm) Well drained Each horizon has only one color (except lithological color), and mottles < 2% Sonn et al. (2020) Moderately well drained Mottles (more higher value, less lower chroma than main color) are 0 - 49% on any one of the layers Somewhat poorly drained 20 ≤ ground water level < 50 cm, main color is grayish, 2 ≤ mottles (by oxidation) < 50% in 20 - 50 cm from soil surface Poorly drained 20 ≤ ground water level < 50 cm, main color is grayish, mottles (by oxidation) < 2% in 20 - 50 cm from soil surface Very poorly drained ground water level < 20 cm, main color is grayish, mottles (by oxidation) < 2% in 0 - 20 cm from soil surface - COLLAPSE
Journal Informaiton
Korean Journal of Soil Science and Fertilizer
Korean Journal of Soil Science and Fertilizer
Korean Society of Soil Science and Fertilizer
한국토양비료학회
Room 313, National Institute of Agricultural Science, 166, Nongsaengmyeong-ro, Iseo-myeon, Wanju-gun, Jeollabuk-do, Korea, 55365
Tel: +82-63-226-7335 / Fax: +82-63-226-7335 / E-mail: ksssf733@naver.com Copyright© Korean Society of Soil Science and Fertilizer. Powered by APUB
Tel: +82-63-226-7335 / Fax: +82-63-226-7335 / E-mail: ksssf733@naver.com Copyright© Korean Society of Soil Science and Fertilizer. Powered by APUB
