Current Issue 2022. Vol.41, Iss.1

Orginal Articles

• Evaluation of Residues of Fungicide Azoxystrobin in Radish based on Plant Back Interval Experiment

  Ji Hyun Yoon, Da Jung Lim, Seon Wook Kim, In Seon Kim / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 1-8

  https://doi.org/10.5338/KJEA.2022.41.1.01

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The pesticide residue in rotational crop is one of the main concerns to agricultural products because it has the potentiality of violating positive list system (PLS). Thus, the crops used for the rotational cultivation should be considered the pesticide residue patterns to meet the PLS guideline. In this study, we evaluated the residue patterns of fungicide azoxystrobin in radish based on plant back interval (PBI) experiment.

  METHODS AND RESULTS:

  Azoxystrobin was treated onto greenhouse soil at 217 g a.i./10a in two different regions. Radishes were sown onto the soil 30 and 60 days after azoxystrobin treatment. The soil and plant samples were subjected to a modified QuEChERS method and LC/MS/MS analyses to determine the residues of azoxystrobin. The methods were validated to meet the guidelines of the pesticide residue analysis recommended by the Rural Development Administration, Republic of Korea. Azoxystrobin was dissipated significantly in soil during the experimental period and found as a level less than 0.01 mg/kg in radish 30 and 60 days after treatment. Azoxystrobin residues in radish samples were lower than the maximum residue limit (MRL) for root vegetables.

  CONCLUSION(S):

  This study suggests 30 days as a PBI for rotational cultivation of radish in greenhouse soil that had been treated with azoxystrobin at a level of 217 g a.i./10a.

• Assessment of Soil Pollutant Distribution Characteristics and Heavy Metal Pollution in Korea

  Jong Cheol Lee, Min Woo Kang, Gyu Hyuk Choi, Se Jin Oh, Dong Jin Kim, Sang Soo Lee / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 9-15

  https://doi.org/10.5338/KJEA.2022.41.1.02

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  Heavy metals discharged from various sources contaminate the soil and water and the residuals can persistently be accumulated. In this study, the concentration of soil heavy metals was assessed over the whole regions of Korea based on the contamination factor and the geoaccumulation index.

  METHODS AND RESULTS:

  The data of averaged concentrations of heavy metals and fluorine were collected from the Korean Statistical Information Service (KOSIS) and the research papers published. In order to classify the levels of heavy metal concentration, the contamination index, including the contamination factor and the geoaccumulation index, based on the relative ratio of the actual concentration of heavy metals in the soil to the background concentration was calculated. In addition, the distribution of heavy metals in soils was visualized by using the geographic information system (GIS). As a result, the Cd contamination in the soils was the most concerned.

  CONCLUSION(S):

  This study very roughly indicated the outline of heavy metal concentration over the whole regions of Korea. The change in heavy metals’ concentration over the time should further be monitored and the larger data of heavy metal contamination are needed for better understanding in the future.

• Climate Change and Rice Yield in Hwaseong-si Gyeonggi-do over the Past 20 Years (2001~2020)

  Ok-Jung Ju, Byoung-Rourl Choi, Eun Kyu Jang, Hoseup Soh, Sang-Woo Lee, Young-Soon Lee / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 16-23

  https://doi.org/10.5338/KJEA.2022.41.1.03

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  Rice production by the current standard cultivation method is predicted to decrease due to global warming. It seems that there has been a strong warming trend in Hwaseong-si, Gyeonggi-do. This study attempted to understand the climate change in Hwaseong-si, Gyeonggi-do and to analyze the effect of climate change on rice production.

  METHODS AND RESULTS:

  The statistical and physicochemical analyses were performed using the rice cultivar ‘Chucheongbyeo’ yields grown at the rice paddy field plot in the Gyeonggi-do Agricultural Research and Extension Services and the weather data measured in near the rice paddy plot.

  CONCLUSION(S):

  There was no significant difference between the average rice yields per area in 2000s (2001~2010) and 2010s (2011~2020), but the rice yield variability was greater in 2010s than in 2000s. The mean, minimum, maximum temperature, and the sunshine hours were evaluated for the correlation with the rice yield. The understanding of climate change in Hwaseong-si, Gyeonggi-do and the major weather factors affecting changes in rice yield, presented in this study, would enhance scientific understanding of regional climate change, and improve rice cultivation management.

• Evaluation of Water Absorption Speed for Litter Materials to Improve the Water Control Ability of Livestock Litter

  Jun-Suk Rho, Jae-Hoon Lee, Su-Lim Lee, Jong-Hwan Park, Dong-Cheol Seo / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 24-31

  https://doi.org/10.5338/KJEA.2022.41.1.04

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The most common litter materials used in South Korea are sawdust, rice husk, etc. Recently, the cost of litter has been steadily rising, and the maturity test has been strengthened. For this reason, new litter materials are needed for better water control ability to solve the problems. The object of this study was to evaluate the water absorption properties for litter materials.

  METHODS AND RESULTS:

  The volumetric water capacity according to the addition of cow manure was investigated to calculate the water absorption speed of litter materials (sawdust, peatmoss, cocopeat, and biochar). The water absorption speed constant (-K) in the first stage was high in the order of cocopeat (0.1190), sawdust (0.0961), biochar (0.0762), and peatmoss (0.0523). The optimal period of the litter use was in the following order: peatmoss (48d), biochar (42d), sawdust (30d), and cocopeat (24d). The water absorption rate (%) of the used litters was high in the order of biochar ≈ cocopeat, sawdust, and peatmoss, which was significantly correlated with the water absorption speed of the first stage.

  CONCLUSION(S):

  Considering the water absorption speed and water absorption rate, biochar and peatmoss were found to be the best and optimal litter materials among the tested materials. These litter materials can be used as water control agents in livestock facilities.

• Climate-Smart Agriculture(CSA)-Based Assessment of a Local Rice Cultivation in Hwaseong-city, Gyeonggi-do

  Ok Jung Ju, Hoseup Soh, Sang-Woo Lee, Young-Soon Lee / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 32-40

  https://doi.org/10.5338/KJEA.2022.41.1.05

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  Climate-smart agriculture (CSA) has been proposed for sustainable agriculture and food security in an agricultural ecosystem disturbed by climate change. However, scientific approaches to local agricultural ecosystems to realize CSA are rare. This study attempted to evaluate the weather condition, rice production, and greenhouse gas emissions from the rice cultivation in Hwaseong-si, Gyeonggi-do to fulfill CSA of the rice cultivation.

  METHODS AND RESULTS:

  Over the past 3 years (2017~2019), Chucheong rice cultivar yield and methane emissions were analyzed from the rice field plot (37°13′ 15″N, 127° 02′22″E) in the Gyeonggi-do Agricultural Research and Extension Services located in Gisan-dong, Hwaseong-si, Gyeonggi-do. Methane samples were collected from three automated closed chambers installed in the plot. The weather data measured through automatic weather station located in near the plot were analyzed.

  CONCLUSION(S):

  The rice productivity was found to vary with weather environment in the agricultural ecosystem. And methane emissions are high in a favorable weather condition for rice growth. Therefore, it is necessary to minimize the trade-off between the greenhouse gas emission target for climate change mitigation and productivity improvement for CSA in a local rice cultivation.

• Ammonia Gas Emission Factor at different Application Rate of Urea in Chinese Cabbage Cultivation

  Su-Lim Lee, Jae-Hoon Lee, Jun-Suk Rho, Yu-Jin Park, Ah-Young Choi, Sin-Sil Kim, Seul-Rin Lee, Jong-Hwan Park, Dong-Cheol Seo / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 41-49

  https://doi.org/10.5338/KJEA.2022.41.1.06

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The main source of ammonia in soils, South Korea is agricultural emissions (e.g., fertilizer application and livestock manure), with the recent emission inventories reporting them to be approximately 80% of the total emissions. Ammonia as a pollutant is originated largely from agricultural activity and is an important contributor to air quality issues in South Korea. The importance of ammonia in agricultural land is also emerging. In this study, the characteristics of ammonia emission from Chinese cabbage cultivation fields with application rates of urea sere were evaluated.

  METHODS AND RESULTS:

  The ammonia emission characteristics were investigated at the different urea application rates (0, 160, 320, and 640 kg ha^-1) and the ammonia emission factor in the Chinese cabbage cultivation field was calculated. As application rate of urea application increased, ammonia emissions increased proportionally. In 2020 and 2021, cumulative ammonia emissions with urea 320 kg ha^-1 treatment were 39.3 and 35.2 kg ha^-1, respectively for 2020 and 2021. When urea fertilizer was applied, the ammonia emission factors were 0.1217 and 0.1358 NH₄⁺-N kg N kg^-1 in 2020 and 2021, respectively.

  CONCLUSION(S):

  Ammonia emissions increased as application rate of urea increased, and the average ammonia emission factor of the Chinese cabbage cultivation field for two years was 0.129 NH₄⁺-N kg N kg^-1.

• Identification of Polyphenol Substances (MP-1) from Seagrass, Phyllospadix Japonica Makino

  Hae-Seon Kim, Nyun-Ho Park, Ho-young Suk, Sang-guan You, Jung-Hee Woo / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 50-54

  https://doi.org/10.5338/KJEA.2022.41.1.07

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  Phyllospadix japonica Makino is a perennial plant belonging to the family Zosteraceae. This species is native to the eastern coast of the Korean Peninsula, and it is found attached to rocks on the seashore. As with all seagrass species, P. japonica is also known to play a major role in protecting the marine environment, and studies on its physiological activities suggestive of its antioxidant, antibacterial and anti-inflammatory potentials have been reported. In this study, purification and structural analysis were performed to identify the polyphenol substances derived from P. japonica.

  METHODS AND RESULTS:

  An polyphenol substance MP-1 was purified from the 70% aqueous methanol extract of P. japonica using Diaion® HP-20 column chromatography, ODS column chromatography, and mediumpressure liquid chromatography (MPLC). The purified MP-1 was identified as rosmarinic acid having a molecular weight of 360 and a molecular formula of C₁₈H₁₆O₈ through electrospray ionization (ESI)-mass and nuclear magnetic resonance (NMR) spectroscopic analysis.

  CONCLUSION(S):

  This study highlights the processes used for the identification of the polyphenol substance derived from P. japonica. Rosmarinic acid, the polyphenol derived from P. japonica identified by this study, is a kind of bioactive substance mainly present in plants. These findings provide an important starting point and are valuable for future studies on bioactive substances in seagrass.

• Study on Residual Properties and Risk Assessment of α-Cypermethrin and Deltamethrin in the Chives (Allium tuberosum R.) and Spring onion (Allium wakegi Araki)

  Yeong Ju Jo, Jeong Yoon Choi, Hun Ju Ham, Jang Hyun Hur / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 55-64

  https://doi.org/10.5338/KJEA.2022.41.1.08

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  This study was conducted to evaluate the residual characteristics and safety assessment of α-cypermethrin and deltamethrin in minor crops, chives and spring onion cultivated in greenhouse.

  METHODS AND RESULTS:

  The insecticides α-cypermethrin 2% EC and deltamethrin 1% EC used in the experiment were diluted 1,000 times and then sprayed on chives and spring onion twice with 1-week intervals at 0, 7, 14, and 21 days before harvest. The residual insecticides were extracted from the minor crops using QuEchERS method and analyzed by GC-MS/MS. The average initial residues of α-cypermethrin and deltamethrin in chives after 21 days decreased from 2.74 to 0.82 mg/kg and 1.12 to 0.16 mg/kg, respectively. Similarly, in spring onion the residues after the same periods decreased from 0.26 to <0.01 mg/kg for α-cypermethrin and from 0.07 to <0.01 mg/kg for deltamethrin.

  CONCLUSION(S):

  The PHIs (pre-harvest intervals) for α-cypermethrin and deltamethrin in chives are recommended as 14 days before harvest with twice applications of the pesticides, whereas for α-cypermethrin in spring onion PHI of 7 days before harvest is recommended with 3 times of applications and PHI of 21 days for deltamethrin. The theoretical maximum daily intakes of cypermethrin and deltamethrin were 68.8% and 64.2%, respectively, indicating that residues of both compounds did not pose considerable health risks to consumers.

• Hex Code-based Geological Cross-sections Describing Landscape Dynamics in the Jeju Geomunoreum Lava Tube System

  Yun-Jae Yi, Soo-In Kim, Ung-San Ahn, Keun Chul Lee, Mi-Kyung Lee, Jung-Sook Lee, Dae-Shin Kim, Jong-Shik Kim / Korean Journal of Environmental Agriculture / 2022 / v.41, no.1, 65-70

  https://doi.org/10.5338/KJEA.2022.41.1.09

  Abstract Full-Text PDF

  Abstract

  

  BACKGROUND:

  The Geomunoreum Lava Tube System (GLTS) is both vast and culturally valuable. The Jeju Volcanic Island and Lava Tubes, which are partly composed of the GLTS, have been declared as a United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage Site. Exploration of the caves is strictly regulated to conserve these vulnerable environments. Photographs provide limited information and do not describe the entire environment comprehensively. Therefore, we created several illustrations of the lava tubes to display their environmental features.

  METHODS AND RESULTS:

  We explored six lava caves (upstream and downstream) in the GLTS and photographed their geological features and yellow walls, the colors of which are influenced by microbial mats. We compared the hex codes of the wall colors using the Clip Studio v1.10.5 software and created illustrations that accurately represent the scale and features of the caves.

  CONCLUSION(S):

  Upstream and downstream caves of the GLTS differ in scale and volcanic features. We illustrated various characteristics of the caves including lava cave features, vegetation, and microbial mats. We also described the internal and external cave environments.