• Journal of Wetlands Research
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• v.24 no.2
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• pp.69-82
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• 2022

In this study, we investigated the bacterial community structure in organic rice-fish mixed farming paddy soil by using high-throughput sequencing technology. The results showed that compared with the organic rice cultivated soil, the content of AP (available phosphorus) increased by 310.23 % and the content of OM (organic matter) increased by 168.83%. The most abundant phyla in paddy soils were Proteobacteria, Bacteriodetes, and Chloroflexi, whose relative abundance was above 47.83%. Among the dominant genera, the relative abundance of Limisphaera in paddy soils was observed. Alpha diversity indicated that the bacterial diversity of paddy soils was similar among each other. The bacterial community structure was affected by the relative abundance of bacteria, not the species of bacteria. Principal Coordinated Analysis (PCoA) results showed that the bacterial communities in organic rice-fish mixed farming soil and organic paddy soil were correlated to each other; the bacterial community structure was distinctively grouped by four different systems (paddy soil under organic rice-fish mixed farming system, organic rice cultivation, and conventional rice cultivation), where the first two are closely related to each other than the third one. The results provide basal support for organic agri-cultivation while improving an ecological value at the same time.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.705-715
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• 2010

The adoption of carbon foot print system is being activated mostly in the developed countries as one of the long-term response towards tightened up regulations and standards on carbon emission in the agricultural sector. The Korean Ministry of Environment excluded the primary agricultural products from the carbon foot print system due to lack of LCI (life cycle inventory) database in agriculture. Therefore, the research on and establishment of LCI database in the agriculture for adoption of carbon foot print system is urgent. Development of LCA (life cycle assessment) methodology for application of LCA to agricultural environment in Korea is also very important. Application of LCA methodology to agricultural environment in Korea is an early stage. Therefore, this study was carried out to find out the effect of lettuce cultivation on agricultural environment by establishing LCA methodology. Data collection of agricultural input and output for establishing LCI was carried out by collecting statistical data and documents on income from agro and livestock products prepared by RDA. LCA methodology for agriculture was reviewed by investigating LCA methodology and LCA applications of foreign countries. Results based on 1 kg of lettuce production showed that inputs including N, P, organic fertilizers, compound fertilizers and crop protectants were the main sources of major emission factor during lettuce cropping process. The amount of inputs considering the amount of active ingredients was required to estimate the actual quantity of the inputs used. Major emissions due to agricultural activities were $N_2O$ (emission to air) and ${NO_3}^-$/${PO_4}^-$ (emission to water) from fertilizers, organic compounds from pesticides and air pollutants from fossil fuel combustion in using agricultural machines. The softwares for LCIA (life cycle impact assessment) and LCA used in Korea are 'PASS' and 'TOTAL' which have been developed by the Ministry of Knowledge Economy and the Ministry of Environment. However, the models used for the softwares are the ones developed in foreign countries. In the future, development of models and optimization of factors for characterization, normalization and weighting suitable to Korean agricultural environment need to be done for more precise LCA analysis in the agricultural area.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.185-198
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• 2016

Korea has put in significant efforts to increase the number of wildlife crossings between fragmented habitats to prevent loss of biodiversity and to encourage the habitat connectivity in Korea. However, there is a lack of biological data on the effect of vegetation structure in these wildlife crossings and guidelines for design and management of wildlife crossing structures in Korea. Therefore, we selected ground beetle assemblages as model organisms to compare the effect of vegetation structure in wildlife crossings, i.e. bare ground- and shrub-type corridors, in agro-forested landscapes. For this study, 4,207 ground beetles belonging to 33 species were collected through pitfall trapping along the northern forest-corridor-southern forest transects from late April to early September in 2015. Dominant species, abundance, and species richness of ground beetles were significantly higher in the shrub-type corridors than the bare ground-type corridors. Also, the species composition of bare ground-type corridor was significantly different compared to the other habitats such as shrub-type corridor and forests. Similarly, environmental variables were also influenced by vegetation management regimes or trap locations. Collectively, our study clearly indicates that the movement of forest associated ground beetles between forest patches can increase as the vegetation in wildlife crossings becomes complex. Although further studies are needed to verify this, there are indications that the current wildlife crossings that comply with the guidelines may be unfriendly to the movement of ground dwelling arthropods as well as ground beetles. To enhance the ecological function of wildlife crossings, the guidelines need to be rectified as follows: 1) Shrubs or trees should be planted along the corridor verges to provide refuge or movement paths for small mammals and ground dwelling arthropods, and 2) Open spaces should be provided in the middle of the corridors to be used as a path for the movement of large mammals.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.343-348
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• 2007

To assess the environmental risks of transgenic chili pepper with PepEST gene on non-target organisms before it exposes to the agro-ecosystem environments, we conducted the three sets of green peach aphids (Myzus persicas S.) life table experiment under laboratory conditions (Temp. $25^{\circ}C$, R.H. 50-70%, Photoperiod L16 : D8) in series during 2005-2006. We measured the net reproductive rate ($R_0)^*$, the intrinsic rate of increase ($r_m$), the mean generation time ($T_c$), $fecundity^*$, life span, and reproduction period between non-transgenic chili peppers and transgenic chili peppers, respectively. The life span of green peach aphids from three sets was 31, 27, 25 days, and the period of life span was similar to the general average length of green peach aphids, 25-29 days. Although the first reproduction of transgenic pepper was similar to the non transgenic pepper (P>0.05), the fecundity and the net reproductive rate ($R_o$) by using Jackknife method of transgenic pepper were lower than those of non transgenic pepper (P<0.05). Conclusively, we observed the adverse effect from our results but we should execute further experiments to confirm the results at the fields with the similar way.