• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1439-1446
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• 2009

Isocarbophos is a widely used organophosphorus insecticide that has caused environmental pollution in many areas. However, degradation of isocarbophos by pure cultures has not been extensively studied, and the degradation pathway has not been determined. In this paper, a highly effective isocarbophos-degrading strain, scl-2, was isolated from isocarbophos-polluted soil. The strain scl-2 was preliminarily identified as Arthrobacter sp. based on its morphological, physiological, and biochemical properties, as well as 16S rDNA analysis. The strain scl-2 could utilize isocarbophos as its sole source of carbon and phosphorus for growth. One hundred mg/l isocarbophos could be degraded to a non detectable level in 18 h by scl-2 in cell culture, and isofenphos-methyl, profenofos, and phosmet could also be degraded. During the degradation of isocarbophos, the metabolites isopropyl salicylate, salicylate, and gentisate were detected and identified based on MS/MS analysis and their retention times in HPLC. Transformation of gentisate to pyruvate and fumarate via maleylpyruvate and fumarylpyruvate was detected by assaying for the activities of gentisate 1,2-dioxygenase (GDO) and maleylpyruvate isomerase. Therefore, we have identified the degradation pathway of isocarbophos in Arthrobacter sp. scl-2 for the first time. This study highlights an important potential use of the strain scl-2 for the cleanup of environmental contamination by isocarbophos and presents a mechanism of isocarbophos metabolism.

• 한국환경농학회지
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• 제23권1호
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• pp.68-74
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• 2004

억새즙액을 이용하여 유용한 미생물의 대량배양을 위한 새로운 배지를 개발하고자 본 연구를 수행하였다. 억새즙액의 성분을 조사한 결과 칼륨 (37,952 mg/L), 질소 (14,000 mg/L), 인산 (6,800mg/L), 마그네슘 (5,969 mg/L), 칼슘 (5,910 mg/L) 등이 주성분을 차지하였다. 본 연구를 위하여 먼저 식물병원성균인 뿌리썩음병 원인균인 Rhizoctonia solani, 잿빛곰팡이 병을 일으키는 Botrytis cinerea에 대하여 강력한 저해 활성을 갖는 길항균 G-74를 토양으로부터 분리하였으며, 이 균의 형태관찰과 MIDI 분석을 통하여 Bacillus lentimorbus G-74 균주로 최종 동정하였다. 이 균의 억새즙액 배지에 대한 최적 배양조건을 조사한 결과 30% (V/V) 희석배지, $35^{\circ}C$ 배양온도, 5.0의 초기 배지 pH에서 가장 좋은 성장을 기록하였다. 또한 이 배지에 탄소원으로서 2.0% (W/V)의 corn starch 및 질소 원으로서 1.0% (W/V)의 yeast extract를 추가적으로 첨가하면 최상의 성장을 보여주었으며, 이 경우 대조구인 LB 배지보다도 균체성장이 66% 이상 증가하였다.

• 한국유기농업학회지
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• 제15권4호
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• pp.399-411
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• 2007

Korean organic farming has been well developed over the last two decades. It demonstrates that the number of certificated farm for organic agriculture and products have been drastically increased in recent year. However, the organic farmers have thought that organic farming rely only on organic fertilizer and they don't keep organic farming principle in which organic farmer should enhance biological activity and crop rotation. This study was to compare nutrient input, recommendation, cropping system and organic product circulation between the early $20^{th}$ century and beginning of the $21^{st}$ century. The population of Korea has increased 7.3 times more than that of a century ago but cultivated land has been decreased during 100 years. The rice production in 2002 was 4.2 times higher than that of production in 1912. The input of N, P and K in 1907 on the basis of King's suggestion was 95.6kg/ha, 15.9kg/ha and 3.0kg/ha, respectively. Nitrogen came from excreta (40%), green manure (55%) and compost (5%) in the early 20th century. On the other hand, organic farmer input organic resources such as wood chip (30.1%), compost (27.8%), rice straw (14%) and others (25%) these days. In terms of nutrient balance calculated nutrient and absorption by plants, organic rice farmer apply excessive nitrogen and phosphorus to the soil. They was used to put $7{\sim}10$ times more nitrogen than that of a century ago. Nutrient recommendation was similar in N and P between early 20th century and early $21^{st}$ century. Farmers in both century did not rotate crops in the field. Today, organic farmers engaged in more continuous cultivation than in early 20th century. Farmers in the early $20^{th}$ century produced locally, consumed locally the agricultural products, but organic farmers in the $21^{st}$ century produce the organic product in the local farmland and consumed in the large city and also a lot of foreign organic products have been imported in recent year.

• International Journal of Industrial Entomology and Biomaterials
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• 제40권2호
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• pp.41-50
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• 2020

Vermicompost, manure, compost and organic fertilization are ecofriendly. Nowadays, many products resulted from sericulture consumed by humans such as mulberry leaves, fruits, mulberry tea, silk and natural silk cosmetics. Soil applications of three treatments with vermicompost (0.5, 1 and 2 tons per 0.42 hectare) and recommended rate of mineral fertilizers of nitrogen phosphorus potassium were used for investigation. Impact of fertilization on mulberry plant traits of moisture, number of shoots/tree, total shoots length/tree, number of leaves/shoot, number of leaves/ (100g), leaf yield/tree and leaf yield of fadden/season were recorded. In addition the effect of fertilization on larval and cocoon characters of young instar duration, fifth instar duration, total larval duration, larval mortality percentage, weight of third instar larvae, weight of fourth instar larvae, weight of fifth instar larvae, fresh cocoon weight, fresh shell weight, pupae weight, cocoon shell ratio, silk productivity, cocooning percentage, pupation ratio, number of cocoons/ liter, crop cocoons by number, crop cocoons by weight, fecundity and fertility. Using vermicompost treatment was enhancing plant characters. Treatments of V₃, V₂ and V₁ were shortage young, fifth and larvae durations. Mostly feeding silkworm during the whole larval duration on treated mulberry leaves with vermicompost improving the traits average. Using vermicompost for fertilization by rate of V₃ and V₂ is better than others for cocoon characters for females and males.V₃ and V₂ of vermicompost per 0.42 hectare is recommended for rearing mulberry silkworm instead of mineral fertilization.

• 생물환경조절학회지
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• 제15권1호
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• pp.8-20
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• 2006

This research was conducted to determine the plant growth and nutrient contents of potted chrysanthemum 'Lima Honey' as influenced by application rate of dolomite in three root media, peatmoss+vermiculite (1:1, v/v), peatmoss+composted rice hall (1:1, v/v), and peatmoss+composted pine bark (1:1, v/v). All root media contained polyacrylic acid sodium salt (PASS) at a rate of $4.5g L^{-1}$. In crop growth at 40 and 80 days after transplanting, elevated application rates of dolomite up to $6.0g L^{-1}$ in three root media increased fresh and dry weights per plant. But the treatment of $9.0g L^{-1}$ had less fresh and dry weights than those of $6.0g L^{-1}$. Tissue phosphorus content decreased and those of Ca and Mg increased by the elevated application rates of dolomite. Elevated application rates of dolomite in three root media resulted in the increase of pH, EC, and the concentrations of K, Ca, and Mg at 43 days after transplanting. Those at 80 days after transplanting were also increased, but the differences among treatments were less significant as compared to those at 43 days after transplanting. From the results of dry weight in potted chrysanthemum 'Lima Honey', the proper application rate of dolomite to three root media containing PASS at a rate of $4.5g L^{-1}$ were $6.0g L^{-1}$.

• 한국농공학회논문집
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• 제60권1호
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• pp.11-20
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• 2018

This study is to calibrate the SWAT (Soil and Water Assessment Tool) water quality of SS (Suspended Solid), T-P (Total Phosphorus), and T-N (Total Nitrogen) by focusing on 2014~2015 drought periods and identify the important parameters. For Gongdo watershed ($366.5km^2$), the SWAT was calibrated for 2 cases of 2002~2006 normal year focusing calibration and 2014~2015 drought focusing calibration respectively. The parameters of N_UPDIS (Nitrogen uptake distribution parameter) and CMN (Rate factor for humus mineralization of active organic nutrients) played important roles for T-N calibration during drought periods. The SWAT SS, T-N, and T-P average $R^2$ (Coefficient of determination) results by focusing on 2014~2015 drought periods calibration showed 0.71, 0.65 and 0.62 while 2002~2006 normal year focusing calibration showed 0.63, 0.58 and 0.50 respectively. Also SWAT SS, T-N, and T-P model efficiency NSE (Nash-Sutcliffe efficiency) results by focusing on drought period (2014~2015) calibrated showed 0.76, 0.77, 0.87 respectively. Even though the SS, T-P parameters were unchanged during the calibration, the SS and T-P results were improved by the hydrological parameters (SCS-CN, SOL_K, SLSOIL) during the drought periods. The SWAT water quality calibration needs to be considered for the movement of SS and nutrients transport especially focusing on the drought characteristics.

• 한국식품영양과학회지
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• 제23권1호
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• pp.62-67
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• 1994

본 연구에서는 나물로 가장 많이 사용되는 시금치중 겨울철 비닐하우스 제배 시금치를 데치는 물량과 시간의 변화, 소금의 첨가량(0.5%, 1%, 2%, 3%)에 따른 성분의 변화를 알아본 것으로 그 결과는 다음과 같다. 생 시금치의 일반성분으로는 수분 92.84%, 조단백질 3.0%, 조지방 0.5%, 조회분 1.0%이었다. 비타민 C는 12.88mg%, 인 46.38mg%, 칼슘 37.95mg%, 수산은 710mg% 함유하엿다. 데치는 방법중 데치는 시간과 물량이 증가할수록 대체로 성분의 함량이 감소하였으므로 최대의 영양소를 보존하기 위해서는 가장 적은 물량으로 짧은 시간 처리하는 것이 좋을 것으로 생각된다. 특히 수산함량은 347mg%로 51.1%까지 감소하여 감소폭이 가장 컸다. 데친액에 용출된 환원당 함량은 3.1mg%~4.5mg%로 나타났다. 소금의 첨가량을 달리하여 데친 경우 소금을 첨가하지 않은 경우보다 비타민 C는 오히려 1% 소금 첨가시 그 함량이 13.75 mg%로 61%까지 증가하여 가장 높게 나타났다. 그러나 칼슘과 인의 함량은 약간 감소하였으나 소금 농도간에는 서로 큰 차이가 없었다. 환원당 함량에서도 거의 차이를 보이지 않았다.

• 한국환경생태학회지
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• 제27권1호
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• pp.1-10
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• 2013

본 연구는 산림청의 희귀식물 중 취약종으로 구분되어 있으며 제주도에만 제한적으로 분포하는 갯금불초의 자생지 환경을 조사하여 보전 및 복원 시 기초자료를 제공하고자 하였다. 조사결과 갯금불초의 자생지는 경사 $1-40^{\circ}$의 해안사구에 위치하고 있었으며, 대부분 전사구를 중심으로 띠모양의 군락을 형성하고 있었다. 식생분석결과 7개 지역의 19개 방형구 내에서 조사된 관속식물은 총 38분류군이었다. 중요치는 갯금불초가 44.77%로 가장 높았으며, 다음으로는 순비기나무(13.32%), 좀보리사초(6.75%), 갯메꽃(4.24%), 갯쑥부쟁이(2.54%), 사철쑥(2.43%) 등이 높은 값을 보여 이 분류군들이 갯금불초와 친화도가 높은 것으로 판단된다. 종다양도는 평균 0.79로 산출되었으며, 우점도와 균등도는 각각 0.25와 0.67이었다. 토양분석결과 포장용수량은 4.51%, 유기물함량은 3.37%, pH는 8.17, 유효인산함량은 $1.33{\mu}g/g$, 그리고 전기전도도는 $802.01{\mu}s/cm$로 측정되었다.

• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.257-269
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• 2017

The study has piloted to find the Pattern of species distribution along environmental variables and disturbance in Raghunandan Reserve Forest. Shaltila and Shahapur beat of Raghunandan Hill Reserve Forest are situated in Chunarughat sub-district of Habiganj district between $24^{\circ}5^{\prime}-24^{\circ}10^{\prime}N$ and $91^{\circ}25^{\prime}-91^{\circ}30^{\prime}E$ under the Sylhet Forest Division. The Environmental variable and vegetation data were collected from 30 sample plots from each forest beat by using arbitrary sampling without preconceived bias. 51 species were found from Shaltila and 34 species found in Shahapur forest beat. Thus the dataset continued with total 85 species in 60 samples. To determine the relationships between tree species distribution and environmental variables, Canonical Correspondence Analysis (CCA) ordination method were performed separately for two forest beat. In CCA ordination, tree species showed significant variation along environmental gradients in terms of soil organic matter and disturbances (p<0.05) in the case of Shaltila forest. Potassium has a significant relationship with axis 1 and axis 2 in this forest. But Shahapur forest showed no significant relationship between species and environmental variables. Phosphorus has a significantly negative relationship with axis 2 in this forest. Disturbance played as a critical role of this forest thus influencing the distribution of species. The study showed that the distributions of tree species are strongly influenced by disturbance and organic matter in Shaltila and Shahapur forest beat showed no significant relationship between species and environmental variables. Future research should be included more environmental variables with larger study area that identify the most important environmental forces which will drive by species distribution findings in this forest.

• 한국농공학회논문집
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• 제59권6호
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• pp.89-100
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• 2017

The Agricultural Policy/Environmental eXtender (APEX) model was developed to extend EPIC's capabilities of simulating land management impacts for small-medium watershed and heterogeneous farms. APEX is a flexible and dynamic tool that is capable of simulating a wide array of management practices, cropping systems, and other land uses across a broad range of agricultural landscapes. APEX have its own agricultural environmental database including operation schedule, soil property, and weather data etc., by crops. However, agriculture environmental informations the APEX model has is all based on U.S. As this can cause malfunction or improper simulation while simulating highland field. In this study, database for APEX model to be utilized for South Korea established with 44,814 agriculture fields in Pyeongchang-gun, Korea from 2007 to 2016. And assessed domestic applicability by comparing T-P unit load criteria presented by National Institution of Environmental Research and result of APEX model. As a result of APEX model simulation, average T-P value for decade was 6.18. Average T-P of every year except 2011 was in range of 5.37~10.43 and this is being involved into criteria presented by National Institution of Environmental Research. It is analyzed that adjusting slope factor can make the model applicable for domestic agricultural environment.