Inorganic Chemical Fertilizers Research Articles

주요 농작물 생산과정에서의 탄소배출량 산정 및 무기화학비료의 기여도 분석

본 연구를 통하여 우리나라 대표적인 농작물 47개의 탄소배출량을 산정하였다. 또한 농작물 생산 시 주요 요소로 투입되는 무기화학비료의 기여도 분석을 통하여 무기화학비료가 차지하는 탄소배출량을 정확하게 파악하였다. 농작물 중 시설감귤의 탄소배출량이 <TEX>$5.78E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>으로 47개 작물 중 가장 높았으며 시설포도 <TEX>$4.61E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>, 착색단고추 <TEX>$4.34E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>, 인삼 <TEX>$4.23E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>, 시설고추 <TEX>$4.04E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX> 순으로 나타났다. 다음으로 농작물 1 kg 생산 시 발생하는 탄소배출량 중 무기화학비료의 기여도는 생산단계, 사용단계를 모두 포함하여 평균 25.19%를 차지하는 것으로 분석되었다. 정부의 정책, 정부 및 기업의 연구 개발을 통한 고품질 저탄소 비료 생산 보급과 같은 노력이 함께 이루어진다면 농업분야의 온실가스 감축에 큰 역할을 할 것으로 기대된다. Korea is currently underway research to estimate carbon footprint in agriculture centered on the RDA (Rural Development Administration). This study was estimated carbon footprint for major 47 crops. In addition, contribution of inorganic chemical fertilizers, main elements for production of crops were analyzed. The carbon footprint of <TEX>$5.78E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX> for citrus fruit in greenhouse was highest, grape in greenhouse, sweet pepper in greenhouse, ginseng, green pepper in greenhouse were followed by <TEX>$4.61E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>, <TEX>$4.34E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>, <TEX>$4.23E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX>, <TEX>$4.04E+00kg\;CO_2\;eq.\;kg^{-1}$</TEX> respectively. Next, production phase contribution of inorganic chemical fertilizer to carbon footprint of crop 1 kg were analyzed mean value 1.88%, 9.06% for single fertilizers and complex fertilizers respectively. And use phase accounted for mean value 14.24%. Therefore, to reduce the fertilization of inorganic chemical fertilizer will be reduced <TEX>$CO_2$</TEX> from crop production, also greenhouse gas emissions of agricultural sector will be reduced.

Evaluation of Fish Production Using Organic and Inorganic Fertilizer

Efficient usage of fertilizers in organic or inorganic forms show conflicting results in terms of net fish production under various climatic conditions. Manures applied to polyculture ponds as organic fertilizer, require a process of decomposition before the nutritional contents are released, assimilated, and utilized by plankton. On the other hand, inorganic (chemical) fertilizers are granular and concentrated with primary nutrients. Major nutrients such as nitrogen (N) and phosphorus (P) readily dissolve in water in ionic forms of nitrate, ammonium and orthophosphate. The differences in fertilizer solubility (nutrient release rate) and decomposition processes (organic fertilization) make the water quality and biological response distinctively different in inorganic fertilizer applied ponds. Previous research has indicated that one grass carp, Ctenopharyngodon idella, can support the growth of three silver carp. This means the excreta of herbivorous fish can be utilized to fertilize the water and produce plankton for filter-feeding fish to consume. Due to an inconsistent supply of grass foliage, farmers in North Vietnam found it difficult to include an adequate percentage of grass carp to support polyculture operation without supplementary fertilization to maintain adequate levels of natural foods in the pond. This supplementary fertilization, in particular manure application, often impacted water quality, which negatively affected health of grass carp. In the present study, an attempt was made to evaluate the production of grass carp polyculture when N:P were maintained through supplementary organic fertilization. An assessment of organic and inorganic fertilizer application on fish production was also undertaken and compared with grass carp polyculture performance. Fish biomass change and fertilizer treatments had significant interaction (P= 0.001). The fish production was found to be significantly different for organic fertilizer, grass carp + organic fertilizer and inorganic fertilizer treatments. The net fish production was highest (5.6±0.03 tonnes/ hectare) in grass carp + organic fertilizer treatment followed by organic fertilizer (4.0±0.06 tonnes/hectare). The inorganic fertilizer treatment yielded the least with 3.0±0.05 tonnes/hectare. The control ponds with no fertilizer was applied produced only 0.29±0.01 tonnes/hectare.

INTEGRATION OF LIQUID MANURE INTO CONSERVATION TILLAGE CORN SYSTEMS

Intensive cultivation and chemical fertilizer application resulting from traditional management practices insouthwestern Ontario, Canada, require high energy input and cause soil loss. Four field experiments were conducted overthree years in four mixed farms under notillage and minimum tillage corn (Zea mays L.) systems. The effects of fertilizersource and manure application timing, rate, and method on soil nutrient concentrations, corn grain yields, and groundwaternitrate concentrations were investigated. Three experiments included three basic treatments of fertilizer source: inorganic(chemical) fertilizer, liquid manure, and a combination of inorganic fertilizer and liquid manure. The other experimentincluded five treatments: preplant manure with and without incorporation by an aeration implement, sidedress manure withand without incorporation by a disc implement, and sidedress inorganic fertilizer.<br><br>Soil samples (0300 or 0600 mm depth) for analysis of soil nitratenitrogen (NO3N), phosphorus (P), and potassium(K) concentrations were taken periodically each year, including soil residual NO3N concentrations measured in the fall afterharvest. Weed biomass and corn grain yields were also measured. In general, higher NO3N concentrations were observedin those plots where nitrogen sources had been applied shortly before soil sampling. Trends of residual NO3N concentrationsvaried among experiments, and results were inconclusive. Twofold higher P concentrations were observed in the manuredplots than in the inorganically fertilized plots as a result of higher P2O5 inputs from swine manure. Farmers who apply liquidmanure to their notillage cornfields should be prepared for the possibility of additional weed pressure, especially usingpreplant manure application or sidedressing manure without a starter fertilizer. A 6% increased or comparative corn grainyield was achieved using liquid manure as a fertilizer source when weeds were not a problem. Considering the reduced riskof P runoff and the increased yield potential, the combined treatments, including preplant manure with sidedress inorganicfertilizer and starter fertilizer with sidedress manure, are recommended.