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Only a few have evaluated the mitigation of greenhouse emissions and profit analysis along with soil carbon sequestration for corn cultivation. This experiment was conducted to evaluate the carbon sequestration and mitigation of greenhouse gas emissions as well as their profit analysis with different composts mixed with biochar during corn cultivation. This experimental data provided the second year of corn cultivation. The soil type used was clay loam. The application amounts of synthetic fertilizer and biochar were 220–30–155 kg ha−1 (N–P–K) as the recommended amount after soil analysis and 2600 kg ha−1 based on 1.3% of soil bulk density. For the biannual experimental results, it appeared that carbon sequestration in cow manure cooperated with biochar was highest at 2.3 tons ha−1 and recovered from 67.3 to 78.5% with biochar application. Furthermore, mitigation of CO2-eq. emission as greenhouse gases was estimated to be at 7.3–8.4 MT ha−1, and its profit was evaluated from $7.2 to 8.4 as lowest, from $57.2 to 66.6 as medium and from $139.7 to 162.7 as highest per hectare regardless of organic compost types used. For agricultural practice in Korea, it is evaluated that the market price of CO2 in corn field cooperated with 2600 kg ha−1 of biochar application ranged from $57.2 to 162.7 per hectare in Korean Climate Exchange. For corn biomass, the treatment with biochar application did not significantly decrease compared with the only organic compost application. Based on these experimental results, it might be applied for carbon trading with clean development mechanism for agricultural practices.

Greenhouse-gas emission factors are widely used to estimate emissions arising from a defined unit of a specific activity. Such estimates are used both for international reporting to the United Nations Framework Convention on Climate Change (UNFCCC) and for myriad national and sub-national reporting purposes (for example, European Union Emissions Trading Scheme; EU ETS). As with the other so-called "Kyoto protocol GHGs", the Intergovernmental Panel on Climate Change (IPCC) provides a methodology for national and sub-national estimation of N₂O emissions, based on the sector from which the emissions arise. The objective of this study was to develop a integrated emission factor to estimate the direct N₂O emission from an agricultural field cultivated with the red pepper, soy bean, spring cabbage, autumn cabbage and potato in 2010∼2012. Emission factor of N₂O calculated using accumulated N₂O emission, N fertilization rate, and background N₂O emission over three year experiment was 0.00596±0.001337 kg N₂O-N (N kg) -1 . More extensive studies need to be conducted to develop N₂O emission factors for other upland crops in the various regions of Korea because N₂O emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

Environmental effect of water-saving irrigation on the emissions of greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of water-saving irrigation on GHGs as well as water use and rice production yield in paddy field condition in Korea. Four experimental runoff plots of 4x35 m in size were prepared at an existing paddy field. GHGs emission was measured during the 2012∼2013 growing seasons while a Japonica rice variety was cultivated. Four different water management methods, 1) Continuous Flooding (CF), 2) Intermittent Drainage (ID), 3) Water Saving (WS), and 4) CF+WS, were used during a rice growing season to compare the effects of water management methods on GHGs emission. CF method is flooding all the time, ID method makes paddy water drained 40 days after transplanting for about two weeks, WS method maintains 2~3 ㎝ water-level, which should be refilled when the water-level decreased to about 0 ㎝, and CF+WS method combines CF method before 30 days after transplanting (DAT) and WS method after 30 DAT. Regardless of water management methods, paddy field water was drained about 30 days before harvest. Amount of GHGs emission from WS plot was reduced by 69.3% compared to that from CF plot and by 59.0% compared to that from ID plot. Amount of GHGs emission from CF+WS plot was reduced by 60.7% compared to that from CF plot and by 47.5% compared to that from ID plot. Weed occurrence in CF+WS plots was reduced to 62.2% in comparison with the WS plot, implying that CF+WS plot showed the best effect to mitigation of the greenhouse gas emission in the atmosphere.

Although intermittent drainage is regarded as a key factor to reduce methane (CH4) emission from paddy soil during rice cultivation, it also could increase nitrous oxide (N2O) emission. However, the effects of intermittent drainage on CH4 and N2O emissions with different global warming potential (GWP) values have not been well examined. In the present study, the effect of a 26-day intermittent drainage from the 34th day after transplanting (DAT) to the 60th DAT on two greenhouse gas (GHG) fluxes and yield properties were compared with those of a continuous flooding system under different fertilization (NPK as control, PK, and NPK+straw) during rice cultivation. The effect of intermittent drainage on changing two GHG emissions was compared using the GWP value, calculated as CO2 equivalents by multiplying 25 and 298 to the seasonal CH4 and N2O fluxes, respectively. Under the same irrigation condition, addition of nitrogen to PK significantly increased seasonal CH4 and N2O fluxes, and addition of straw to NPK increased CH4 and N2O. Irrespective with fertilization background, the intermittent drainage significantly reduced the total GWP by ca. 41–70% as affected by the big reduction of seasonal CH4 fluxes by ca. 43–53% to that of the continuous flooding even with an increase of seasonal N2O emissions by ca. 16–43%. Rice productivity was not significantly different between the two different irrigation systems under same fertilization background. As a result, total GWP per grain yield was significantly lower in all fertilization treatments with intermittent drainage compared with continuous flooding.

Under intensive vegetable production, increased productivity is primarily considered for selecting better water management and irrigation intensity in upland soils. Soil water potential at −30 kPa (field capacity) for red pepper (Capsicum annum L.) production, which is the optimum moisture potential for plants, is recommended for Korean upland soils to maximize fruit yield; however its impact on greenhouse gas (GHG) emissions have not yet been considered. In this study, red pepper was cultivated under two soil water potentials at −30 and −50 kPa by drip irrigation control in two different textured soils (clay and sandy loams). Nitrous oxide (N2O) and methane (CH4) emissions were simultaneously investigated during the cultivation period. Results indicated N2O was the main GHG and contributed to approximate 97–9% of the total global warming potential (GWP), though the extent of its contribution varied depending on soil texture and soil moisture control with emitted CH4 being negligible throughout the investigation period. Between the treatments, soil moisture control at −50 kPa was effective in reducing the emissions of the two GHGs and also increased red pepper productivity in both clay loam and sandy loam soils. Comparing the gross GWP per unit pepper fruit yield between the treatments, maintaining soil water potential at −50 kPa by controlled irrigation led to a 50% reduction of GWP per unit pepper fruit yield. Therefore, drip irrigation control to lower soil water potential at −50 than −30 kPa is recommended to obtain high crop yield and reduce GWP per unit red pepper fruit yield for red pepper production in Korea.

The effects of water-saving irrigation on the emissions of greenhouse gases and the prokaryotic communities in rice paddy soils were investigated through a field experiment. In the Water-Saving (WS) irrigation, the water layer was kept at 2~3 cm while it was kept at 6 cm in the Continuousiy Flooding (CF) irrigation. A plot was treated with Intermittently Drainage (ID) that is drained as fine cracks on the floor were seen after transplanting. GHGs emission amounts from WS plots were reduced by 78.1% compared to that from CF plot and by 70.7% compared to that from ID plot, meaning that WS could help contribute to mitigation of the greenhouse gas accumulation in the atmosphere.

Rice cultivation in the paddy field and the burning of crop residues have been identified as the important sources of methane emission in agricultural sector. This study aimed at assessment of the methane emission from croplands in the year of 2011 with the IPCC guideline methodology. Methane from rice cultivation was emitted 6,813 CO₂-eq Gg in 2011. According to the water management, methane emission amounts by continuously flooded and intermittently flooded were 1,499 and 5,314 CO₂-eq Gg, respectively. Methane emission by crop residues burning was highest in red pepper and followed by rice straw, pulses and barely in 2011. Methane emission by field burning was very little compared with rice cultivation.

Water control is mainly one of the key factors that can affect nitrous oxide (N 2 O) emissions from soils. This study was undertaken to determine the effect of intermittent drainage compared to continuous flooding (conventional water regime) on N 2 O emission to global warming potential (GWP) with NPK (standard cultivation practice), NPK+Straw, and PK fertilizations. Nitrous oxide emission rates were collected twice a week using a closed chamber method. With continuous flooding, nitrogen (N) application increased N 2 O emission by 106.6% (0.64 kg ha -1 in NPK) with respect to the PK treatment (0.31 kg ha -1 ), and straw addition to NPK enhanced 148.3% of seasonal N 2 O flux (0.77 kg ha -1 in NPK+Straw). Although seasonal N 2 O emission slightly increased by 16.1-42.9% with intermittent irrigation, its seasonal CH 4 emission drastically reduced at 43.5-52.8% resulting in a lower GWP at 48.9-58.5% with respect to that of continuously flooded treatments (4.51 Mg CO 2 ha -1 , PK; 7.60 Mg CO 2 ha -1 , NPK; 14.55 Mg CO 2 ha -1 , NPK+Straw). Rice yield, at similar fertilization with the continuously-flooded rice field, was not affected by intermittent irrigation. Conclusively, intermittent irrigation can be very effective and a rational soil management strategy to mitigate GWP with considering rice productivity in a temperate paddy rice field like Korea.

This study was performed a comparative life cycle assessment (LCA) among three rice production systems in order to analyze the difference of greenhouse gases (GHGs) emissions and environment impacts. Its life cycle inventory (LCI) database (DB) was established using data obtained from interview with conventional, without agricultural chemical and organic farming at Gunsan and Iksan, Jeonbuk province in 2011. According to the result of LCI analysis, was mostly emitted from fertilizer production process and rice cropping phase. and were almost emitted from rice cultivation phase. The value of carbon footprint to produce 1 kg rice (unhulled) on conventional rice production system was 1.01E+00 kg -eq. and it was the highest value among three rice production systems. The value of carbon footprints on without agricultural chemical and organic rice production systems were 5.37E-01 -eq. and 6.58E-01 -eq. , respectively. Without agricultural chemical rice production system whose input amount was the smallest had the lowest value of carbon footprint. Although the yield of rice from organic farming was the lowest, its value of carbon footprint less than that of conventional farming. Because there is no compound fertilizer inputs in organic farming. Compound fertilizer production and methane emission during rice cultivation were the main factor to GHGs emission in conventional and without agricultural chemical rice production systems. In organic rice production system, the main factors to GHGs emission were using fossil fuel on machine operation and methane emission from rice paddy field.

Water competition among domestic, industrial and agricultural sectors has been gradually heightened recently in Korea as the lack of water supply is expected in the near future. About 46% of nation's water use is consumed in paddy farming to produce rice. And the conservation of water resource and quality in agricultural sector is a pending issue in the nation's long term water management plan. New paddy rice farming techniques that use significantly less irrigation water are urgently required. System of Rice Intensification (SRI) that is now well known to produce more rice with less water consumption has not been tried in Korea yet. And environmental effect of SRI on greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of SRI on GHGs as well as water use and rice yield in a Korean paddy condition. Three experimental runoff plots in size were prepared at an existing paddy field. Runoff, GHGs emission and water quality were measured during the 2011 growing seasons while a Japonica rice variety was cultivated. Rice plants grew better and healthier in SRI plots than in continuously flooded (CF) and intermittently drained (ID) plots. Rice yield from SRI plots increased 112.8 (ID)~116.1 (CF)% compared with CF and ID plots. Irrigation requirement of SRI plots compared to CF plot reduced by 52.6% and ID plot reduced by 62.0%, meaning that about 37.9~47.4% of irrigation water could be saved. GHGs emission from SRI plots reduced by 71.8% compared to that from CF plot and by 18.4% compared to that from ID plot, meaning that SRI could help contribute to ease the greenhouse gas accumulation in the atmosphere. It was believed that SRI is a promising paddy farming technique that could increase rice yield, and reduce irrigation water requirement and GHGs emission not just in Korea but also other rice farming countries all over the world. However, it was recommended that long term studies under different conditions including rice variety, soil texture, water source, climate need to be conducted for reliable data for the development of environmental policies related to GHGs emission control and management.

The importance of environment-friendly agriculture is being magnified as a new growth engine industry in pursuit of low carbon, green growth policies. Since 2010, the Korean government has been promoting the supply of customized fertilizers which were manufactured based on chemical properties of agricultural soils. This aims focused to improve the efficiency of fertilizer used and to protect the agricultural environment. In order to provide technical supports for pushing ahead with the environment-friendly agriculture policies, we have estimated the effects of customized fertilization (CF) on growth and yield of rice and fertilizer reduction compared to conventional fertilization (farm practice fertilization) and single-element fertilization. In rice plant growth and rice yield, no statistically significant difference between the three fertilization treatments was observed. The fertilizer reduction rate with CF compared to conventional fertilization of investigated farms was on average 17%, which covered 6% through 33%. With split ratio, CF 70 reduced the amounts of fertilizer ingredient by 5% compare to CF 50. This paper shows that the customized fertilizer application reduced the amounts of fertilizer used in rice cultivation without decrease of yields.

Polyethylene mulches have been used for weed control in vegetable production in Korea. One of the additional benefits associated with polyethylene mulches is soil warming. The objective of this study was to evaluate the effects of colored mulches on soil temperature change and Chinese cabbage yield. Mulch treatments were green (GV), black (BV), transparent (TV), and non-mulched (NM) soil. The highest soil-warming effect occurred under green mulch, and the lowest effect was found under black mulch. Daily mean values of soil temperature (10 cm depth) under GV were higher than in NM soil. At midday (16:00), mean soil temperature was higher by in GV, in BV, and in TV as compared to NM soil. At night (20:00-06:00), there was no significant difference in soil temperature among the treatments of different colored mulch, but soils in the mulch treatments were higher as compared to NM soil. As compared with NM, the yield of Chinese cabbage under GV, BV, and TV were higher by 6.0, 26.0, and 12.0%, respectively.

Organic fertilizers application has become a popular alternatives to reduce the dependence on chemical fertilizer in Korean farming systems. In this study, we evaluated the nitrogen (N) use efficiency and growth performance of Chinese cabbage grown by black vinyl mulching after application of organic and chemical fertilizers compared with no-mulching. The treatments included chemical fertilizer alone as control (NPK, N- : ), organic fertilizer alone (OF100), 70% organic fertilizer and 30% chemical fertilizer (OF70+N30), and 30% organic fertilizer and 70% chemical fertilizer (OF30+N70), which were all applied in the no-mulching plots and in plots with black vinyl mulching. Daily means soil temperature was higher in the black vinyl mulched treatments throughout the 54 days compared with no-mulched treatments. OF100 with black vinyl mulching gave highest soil inorganic N content. Also, Chines cabbage yield increased 46% by black vinyl mulched compared with no-mulching in OF100 treatment. Without mulching, N use efficiency was, 44, 26, 29, and 27% in NPK, OF100, OF70+N30, and OF30+N70, respectively. However, black vinyl mulching much more effectively increased N use efficiencies by 56, 55, 51, and 39% in the same treatments in the order as mentioned above. Conclusively, combined organic and chemical fertilizers application with black vinyl mulching could be good practical technique to reduce a amount of used nitrogen because of its greater ability to enhance N use efficiency.

The importance of environment-friendly agriculture is being magnified as a new growth engine industry in pursuit of low carbon, green growth policies. In order to provide technical supports for pushing ahead with the environment-friendly agriculture policies, we estimated the effects of customized fertilization on growth and yield of rice and fertilizer reduction compared to conventional fertilization and single-element fertilization. In rice plant growth and rice yield, no statistically significant difference between the three fertilization treatments was observed. In contrast, customized fertilization showed high disaster resistance reducing the damage caused by rice lodging during a typhoon. The average N application in farms showing high rice lodging amounted to while was known as the critical range of rice lodging in Korea. The fertilizer reduction rate of customized fertilization compared to conventional fertilization of investigated farms was on average 22.5%. We estimated the short-term effects of customized fertilization in the first year after application. In future, there is need for continuous examination of rice growth and soil environment change due to successive application of customized fertilizer.

Organic farming is rapidly expanding worldwide. Crop growth in organic systems greatly depends on the functions performed by soil microbes, and nutrient supply weed suppression by green manure crops input. Four red-pepper production systems were compared: 1) bare ground (conventional system); 2) hairy vetch monoculture; 3) rye monoculture; and 4) hairy vetch-rye mixture. Soil inorganic N reached the peak at 30 DAI and hairy vetch monoculture was the highest (192 mg kg -1 ) and soil total carbon was fluctuated sporadically during the experiment. Carbohydrate and phenolic compounds in soil kept significantly higher in green manure crops systems from 10 DBI to 30 DAI, however the level was the maximum at 10 DBI (carbohydrate) and 30 DAI (phenolic comounds). Incorporation of green manure crops residue enhanced soil microbial biomass C and N throughout the growing season except that MBN in rye was reduced after incorporation. Green manure crops systems suppressed weed occurrence and, in particular, it was prominent in rye monoculture. Mineral elements composition and production in red-pepper fruits were markedly decreased in green manure crops systems although hairy vetch monoculture has come close to bare ground (NPK-applied). Therefore, it was suggested that higher biomass production should be performed not only to improve soil quality and suppress weeds but to yield suitable red-pepper fruits in green manure crops-based organic farming.

The nitrogen, phosphorus, and potassium contents are the key factors to determine the quality of organic fertilizers and right amount of application for agricultural uses. The major nutrient contents in raw materials used for making organic fertilizers and products were evaluated in this study. Among the raw materials that were investigated, soybean cake gave the highest total N content at , followed by perilla cake (), rape seed oil cake (), cotton seed cake (), and rice bran (). We investigated 43 organic fertilizers and our results showed widely varied concentrations of major nutrients : total N at , total at , and total at . Our study would like to emphasize the importance of nutrient content labeling in packed organic fertilizers to be able to know its efficiency and for determining the right amount for application.

To establish the optimum nitrogen level for rice planting after Italian ryegrass cultivation, one experiment was conducted on a normal paddy soil (Jeonbug series soil taxonomy) with six different nitrogen treatments for two years from 2009 to 2010. The treatments were including no nitrogen fertilization (Free N), 50%-Basal N, 75%-Basal N, 100%-Basal N, 150%-Basal N and 100% of basal fertilization with (100%+N30-Basal N) for decomposing of Italian ryegrass stubble. The highest rice yields were 8,420 obtained by 100%-Basal N. 150%-Basal N and 100%+N30-Basal N produced a rice yield of . Those of 50%-Basal N and Free N were produced 8,020 and , respectively. The correlation between rice yield and nitrogen treatment showed a quadratic relationship in high significant. According to this regression, the highest level of nitrogen treatment was and the highest rice yield was . Nitrogen uptake rates were relatively higher with lower amounts of nitrogen fertilizer treated.

This study was conducted to assess the impact of agricultural land use on the water quality in mountain village farmlands. Two soil types, paddy and upland soil were analysed for their chemical properties. Although, pH and organic matter contents were not significantly different to each other, concentrations of available P and exchangeable K and Ca were much higher in upland soil compared with those in paddy soil. The results of water quality analysis indicated that, in Goseong-cheon watershed, the nutrients contents were much higher in downstream area than in upstream area. Particularly, the elevation of and T-P were significant during rainy season. When paddy fields coexist with upland fields, SS, T-N, and T-P concentrations in paddy fields were lower than those of upland fields. This may indicate that paddy fields possess an water-purifying ability by absorbing nutrients. This effect may reduce excessive nutrients discharged into the neighboring streams which may cause eutrophication problem. The difference between inflow and outflow of nitrogen and phosphorus during the cultivation period were measured as -98.9 kg and -29.7 kg , which means that nutrient outflow was higher than inflow. This may suggest that much nutrient was discharged during the crop harvest period.

Objective of this study was to access the environmental impacts of the use of discharge water from municipal waste water treatment plant as alternative irrigation resources during drought season for rice cultivation. For the field experiments, it was observed that plant growth and yield characteristics at 20 days of alternative irrigation period with application of FAST (fertilizer application based on soil test) 50% were relatively the same as the control. For the surface water quality, it appeared that ECi (electrical conductivity of irrigation water) and SAR (sodium adsorption ratio) values of DMWT (discharge waters from municipal wastewater treatment plant) irrigation were twofold higher than those of ground water irrigation as the control regardless of fertilization levels. For the irrigation periods, there were not significantly difference between 10 and 20 days of treatments, but ECi and SAR values of surface water were highest at 30 days of irrigation periods at initial rice growing stages. Generally, ECi values of percolation water in all the treatments were gradually increasing until 30days after irrigation, and then decreasing to harvest stage. Overall, it might be considered that there was possibility to irrigate DMWT with application of FAST 50% for 20 days of drought periods at rice transplanting season. Furthermore, efficiency rate of alternative irrigation water for 20 days of drought period was 32.7% relative to the total annual irrigation water for rice cultivation.

This experiment was conducted to investigate heavy metal transition and bioavailability from soil to the edible pare of water dropwort near industrial complex. The soils were collected from the paddies cultivating water dropwort stream sediments, and background soils near industrial complex. The pH values, organic matter, Av. , Ex. Ca content of paddy soils were higher than those measured for nor-contaminated paddy fields in 2003. The contents of Cd and Cu was higher than those of standard level for soil contamination by Soil Environmental Conservation Act in Korea. The pollution index in stream sediments were higher than those of paddies cultivating water dropwort. The geoaccumulation index of heavy metals in paddy soils and stream sediment were in the order Cu>Cd>Ni>Zn>Pb. The rates of 0.1N-HCl extractable heavy metals to total contents in soils were in the order Cd>Cu>Zn>Ni>Pb. In case of Cd and Ni in paddy soils near industrial complex, 0.1N-HCl extractable heavy metals and total content were highly correlated with each other. Heavy metal contents in mot parts were higher than those in top pare of water dropwort. The Zn and Cu transfer factor from soil to the top pare of water dropwort were higher than those of other heavy metals. The bioavailability of water dropwort varied considerably between the different parts and heavy metals. Cd, Cu and Ni contents in water dropwort were correlated with each elements in paddy soils.

The effect of lime on plant availability of heavy metals in soils amended with industrial sewage sludge (ISS) or pig manure compost (PMC) was investigated. A pot experiment with Altari radish (Raphanus sativus) was conducted. Industrial sewage sludge and Pig manure compost were added at 25 and 50 Mg/ha, and lime was added at 3 Mg/ha. Heavy metal contents of ISS treated soils after experiment were higher than those in control (NPK plot) and PMC treatment. Specially, the contents of copper, zinc, nickel and chromium in the 50 Mg/ha of ISS treated soils were higher 1248 times than those in control. Copper, zinc, and nickel contents in Altari radish leaves cultivated at the ISS treated soil exceeded the critical levels of plant toxicity. Copper, zinc, and nickel contents in Altari radish loaves and roots cultivated at the ISS treated soil were reduced by the addition of lime. Copper, zinc, and nickel contents in Altari radish loaves were negatively correlated with soil pH after experiment. It concluded that liming would reduce the uptake of heavy metals by plants and be a temporary method of reclamation at the highly heavy metal accumulated soils by ISS.

The effects of water-saving irrigation on emissions of greenhouse gases and soil prokaryotic communities were investigated in an experimental rice field. The water layer was kept at 1-2 cm in the water-saving (WS) irrigation treatment and at 6 cm in the continuous flooding (CF) irrigation treatment. WS irrigation decreased CH(4) emissions by 78 % and increased N(2)O emissions by 533 %, resulting in 78 % reduction of global warming potential compared to the CF irrigation. WS irrigation did not affect the abundance or phylogenetic distribution of bacterial/archaeal 16S rRNA genes and the abundance of bacterial/archaeal 16S rRNAs. The transcript abundance of CH(4) emission-related genes generally followed CH(4) emission patterns, but the difference in abundance between mcrA transcripts and amoA/pmoA transcripts best described the differences in CH(4) emissions between the two irrigation practices. WS irrigation increased the relative abundance of 16S rRNAs and functional gene transcripts associated with Anaeromyxobacter and Methylocystis spp., suggesting that their activities might be important in emissions of the greenhouse gases. The N(2)O emission patterns were not reflected in the abundance of N(2)O emission-related genes and transcripts. We showed that the alternative irrigation practice was effective for mitigating greenhouse gas emissions from rice fields and that it did not affect the overall size and structure of the soil prokaryotic community but did affect the activity of some groups.