Menu
Open Access Journal

Korean Journal of Environmental Agriculture

p-ISSN 1225-3537
e-ISSN 2233-4173

HOME > Current Issue

Current Issue 2019. Vol.38, Iss.2 Cover image Contents list Print articles

Orginal Articles

  • Assessment of Electrical Conductivity of Saturated Soil Paste from 1:5 Soil‐Water Extracts for Reclaimed Tideland Soils in South‐Western Coastal Area of Korea

    Hyun‐Jin Park, Hye In Yang, Se‐In Park, Bo‐Seong Seo, Dong‐Hwan Lee, Han‐Yong Kim, Woo‐Jung Choi / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 69-75

    https://doi.org/10.5338/KJEA.2019.38.2.11
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    Measurement of electrical conductivity of saturated soil paste (ECe) for assessment of soil salinity is time‐consuming, and thus conversion of EC of 1:5 soilwater extract (EC1:5) to ECe using a dilution factor may be of help to monitor salinity of huge number of soil samples. This study was conducted to evaluate the dilution factor for reclaimed tideland (RTL) soils of South Korea.

    METHODS AND RESULTS:

    Soil samples (n=40) were collected from four RTLs, and analyzed for EC1:5, ECe, and cation compositions of 1:5 soil‐water extract. The dilution factor (8.70) was estimated by regression analysis between EC1:5 and ECe, and the obtained dilution factor was validated by applying to an independent data set (n=96) of EC1:5 and ECe. The ECe measured and predicted was strongly correlated (r2=0.74, P<0.001), but ECe was overestimated by 16% particularly for the soils with high clay content and low sodium adsorption ratio (SAR).

    CONCLUSION:

    This study suggests that using the dilution factor to convert EC1:5 to ECe is feasible method to monitor changes in the soil salinity of the study RTL. However, overestimation of ECe should be cautioned for the soils with high clay content and low SAR.

  • The Effects of Soybean Cultivation on Soil Microorganism Activity

    Gyeryeong Bak, Gyejun Lee, Taeyoung Kim / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 76-82

    https://doi.org/10.5338/KJEA.2019.38.2.12
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    For sustainable agriculture, there are various agricultural practices including low input. Over the last few decades high input of chemical fertilizer and compounds results in environmental pollution and deterioration of soil fertility. Soybean (Glycine max L.) is well known eco-friendly crop due to their symbionts. Soybean has a relationship with nitrogen fixation bacteria called rhizobia. In this research work, we investigated effects of soybean cultivation on soil microorganism activities.

    METHODS AND RESULTS:

    Experiments were conducted in pots and potato cultivation was used as reference. Soil chemical properties were analyzed considering soil nutrient over cropping period. For the soil microbial community analysis, dehydrogenase activity analysis (DHA) analyzed along with denaturing gradient gel electrophoresis. The results showed that higher soil organic matter in the soybean cultivation soil than in the potato cultivation soil. Available P2O5 concentration increased gradually in both pots but showed higher value in the potato cultivation soil. DHA value implying microbial activities showed higher value in the soybean cultivation soil over all cropping period.

    CONCLUSION:

    The cause of high microbial activity in the soybean cultivation soil was considered to the effects of some specific microorganisms related to soybean cultivation. Therefore, the availability of soybean cultivation for sustainable agriculture should be encouraged in terms of microorganism community activity in soil.

  • Evaluation of Cd Adsorption Characteristic by Microplastic Polypropylene in Aqueous Solution

    Ju‐Hyun Eom, Jong‐Hwan Park, Seong‐Heon Kim, Yeong‐Jin Kim, Sung‐Ki Ryu, Dong‐Cheol Seo / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 83-88

    https://doi.org/10.5338/KJEA.2019.38.2.16
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    In recent years, studies on microplastics have focused on their decomposition in the ocean. However, no studies have been reported on the interaction between microplastics and metal ions in aqueous solutions. Therefore, this study was conducted to evaluate the adsorption capacity of cadmium(Cd) by polypropylene (PP) in aqueous solution.

    METHODS AND RESULTS:

    Cadmium adsorption characteristics of PP in aqueous solution were evaluated through various conditions including initial Cd concentration(1.25‐25 mg/L), contact time(0.5-24 h), initial pH(2‐6) and temperature(20‐50℃). Cadmium adsorption fit on PP was well described by Freundlich isotherm model with adsorption capacity(K) of 0.028. The adsorption amount of Cd by PP increased with increasing contact time, indicating that adsorption of PP by Cd was dominantly influenced by contact time. Especially, the removal efficiency of Cd by PP was highest at high temperature. However, the surface functional groups of PP before and after adsorption of Cd were similar, suggesting that adsorption of Cd by PP is not related to surface functional groups.

    CONCLUSION:

    Our study suggests that PP affects the behavior of Cd in aqueous solution. However, in order to clarify the specific relationship between microplastics and metal ions, mechanism research should be carried out.

  • Damages of Young Persimmon Tree as Affected by Application of Immature Liquid Pig Manure

    Seong‐Tae Choi, Yeo‐Ok Park, Gwang‐Hwan Ahn, Eun‐Gyeong Kim, Ji‐Young Son, Wan‐Kyu Joung, Kwang‐Pyo Hong / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 89-95

    https://doi.org/10.5338/KJEA.2019.38.2.13
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    Liquid pig manure (LPM) has been used as an alternative for conventional fertilizers on some gramineous crops. However, its chemical properties varied widely depending on the degree of the digestion. A pot experiment was conducted to determine the responses of persimmon trees to immature (not well‐digested) LPM application.

    METHODS AND RESULTS:

    Ten application levels of immature LPM, consisted of a total of 3 to 30 L in 3‐L increment, were applied during summer to 5‐year‐old ‘Fuyu’ trees grown in 50‐L pots. Increasing the LPM application rate caused defoliation, wilting, and chlorosis in leaves. When applied with the rate of 3 L during summer, the tree produced small fruits with low soluble solids and bore few flower buds the following season, indicating insufficient nutritional status. In trees applied with the LPM rates of 6∼12 L, both fruit characteristics and aboveground growth of the trees appeared normal but some roots were injured. However, application of higher LPM rates than 27 L resulted in small size, poor coloration, or flesh softening of the fruits the current season. Furthermore, the high LPM rates caused severe cold injury in shoots during winter and weak shoot growth the following season. It was noted that the application of higher LPM rate than 9 L damaged the root, even though above‐ground parts of the tree appeared to grow normally.

    CONCLUSION:

    The results indicated that an excessive immature LPM application could cause various injuries on leaves, fruits, and the roots in both the current and the following season.

  • Effect of Organic or Inorganic Selenium and Germanium on Growth Stage of Rice

    Yeon‐Su Kim, Jin‐Hyuk Chun, Young‐Ji Jeon, Hyun‐Nyung Woo, Sun‐Ju Kim / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 96-103

    https://doi.org/10.5338/KJEA.2019.38.2.14
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    This study was conducted to develop selenium (Se)‐ and germanium (Ge)‐enriched rice by foliar spray application of organic or inorganic Se and Ge.

    METHODS AND RESULTS:

    The time and frequency of organic or inorganic Se and Ge treatment were performed at the five main growth stages as followings: effective tillering stage (E), maximum tillering stage (M), booting stage (B), heading stage (H), grain filling stage (G). The main treatment plots were consisted of ① ‘once’ treatment (at each E, M, B, H, G stage, Se/Ge single apply), ② ‘twice I’ (at H + G stages, organic or inorganic Se/Ge apply), ③ ‘twice II’ (at H + G stages, mixture apply of Se + Ge + pesticide). The organic or inorganic Se treatment concentration was 20 and 40 ppm, and the Ge was 50 and 100 ppm. The Se and Ge contents in rice grain (brown rice and polished rice) were analyzed by inductively coupled plasma (ICP). The highest Se content was noted in brown rice ‘twice I’ with Se 40 ppm (1394.06) at H + G stages, but the lowest was in ‘once’ with Se 40 ppm (367.79 μgㆍkg‐1) at B stage. The highest of Se content in polished rice was found in ‘twice I’ of Se 40 ppm (1090.25) at H + G stages, but the lowest was in ‘once’ with Se 40 ppm (403.53 μgㆍkg‐1) at E stage. On the other hand, The highest of Ge content in brown rice was found in ‘twice I’ with Ge 100 ppm (398.66) at H + G stages, but the lowest was in ‘once’ with Ge 100 ppm (139.64 μgㆍkg‐1) at B stage. The highest of Ge content in polished rice was found in ‘twice I’ of Ge 100 ppm (300.29) at H + G stages, but the lowest was in ‘once’ with Ge 100 ppm (142.24 μgㆍkg‐1) at B stage.

    CONCLUSION:

    Se and Ge contents both in brown rice and polished rice treated with organic Se and Ge forms were higher than those of inorganic Se and Ge. Overall results concluded that the supplementation of organic Se and Ge contents in brown and polished rice contents were comparatively higher than the inorganic Se and Ge. This is results also proved that the foliar spray application of organic Se and Ge has positive nutritive effect on the rice for regular consumption.

  • Attraction of the Invasive Hornet, Vespa velutina nigrithorax, by using Bacillus sp. BV‐1 Cultures

    Jeong Eun Lee, Jin Sil Lee, Iksoo Kim, In Seon Kim, Da Jung Lim / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 104-109

    https://doi.org/10.5338/KJEA.2019.38.2.10
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    The invasive hornet Vespa velutina nigrithorax has becomes a public concern in rural and urban South Korea. The technologies are necessary to develop a way to counter V. velutina. In an effort to develop a way to counter V. velutina, we found that a bacillus strain, named Bacillus sp. BV‐1, produces volatile compounds that attract V. velutina.

    METHODS AND RESULTS:

    Field trials of V. velutina attraction were performed using plates and traps containing BV‐1 cultures grown on sugar medium. When the sugar medium and sugar‐grown BV‐1 cultures in the plates were placed close together, V. velutina visited preferably the plates with the BV‐1 cultures. Significantly more V. velutina were caught in the traps containing BV‐1 cultures than in those containing only sugar medium. Headspace solid‐phase microextraction coupled with GC/MS analysis of BV‐1 cultures detected 2‐methyl‐1‐propanol, 3‐methyl‐1‐butanol, 3‐methylbutanoic acid, ethyl hexanoate, 2‐pheylethanol, ethyl octanoate, and ethyl decanoate as the major volatiles.

    CONCLUSION:

    BV‐1 cultures were suggested as potential agents for managing V. velutina as they produce volatile compounds that attract the hornet.

  • Investigation of Residual Organochlorine Pesticides in Apple and Pear Orchard Soil and Fruit

    Sung‐Jin Lim, Jeong‐Hwon Park, Jin‐Ho Ro, Min‐Ho Lee, Hyo‐In Yoon, Geun‐Hyoung Choi, Song‐Hee Ryu, Hye‐Jin Yu, Byung‐Jun Park / Korean Journal of Environmental Agriculture / 2019 / v.38, no.2, 110-118

    https://doi.org/10.5338/KJEA.2019.38.2.11
    Abstract Full-Text PDF

    Abstract

    Close

    BACKGROUND:

    Residual organochlorine pesticides (OCPs) are designated as persistent organic pollutants (POPs) by Stockholm Convention because they bioaccumulate through the food web, and pose a risk of causing adverse effect to human health and the environment. Apple and pear is economic crop in agriculture, and its cultivation area and yield has been increased. Therefore, we tried to investigate the OCPs residue in apple and pear orchard soils and fruits.

    METHODS AND RESULTS:

    Extraction and clean‐up method were developed using the modified QuEChERS method for residual organochlorine pesticides (ROCPs) in apple and pear orchard soil and fruits. Recovery and limit of quantitation (LOQ) of ROCPs in soil and fruits were 75.4‐101.4 and 76.9‐93.4%, 0.03‐0.21 and 0.6‐1.2 μg/kg, respectively. Detected ROCPs in apple and pear orchard soil was 2,4‐DDT, 4,4‐DDD, 4,4‐DDE, 4,4‐DDT, and endosulfan sulfate, the residues were 2.2, 1.9‐48.0, 1.3‐84.1, 90.6‐863.1, and 11.3‐239.0 μg/kg, respectively. But five pesticides in all fruit samples were not detected.

    CONCLUSION:

    These results showed that ROCPs residues in apple and pear orchard soil had no effect on safety of agricultural products.