• Journal of Microbiology and Biotechnology
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• 제34권7호
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• pp.1464-1474
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• 2024

Soil extracellular enzyme plays a vital role in changing soil nitrogen (N) mineralization of rice field. However, the effects of soil extracellular enzyme activities (EEA) and microbial community composition response to N mineralization of rice field under short-term tillage treatment needed to be further explored. In this study, we investigated the impact of short-term (8-year) tillage practices on rhizosphere soil N transformation rate, soil enzyme activities, soil microbial community structure, and the N mineralization function gene abundances in double-cropping rice field in southern China. The experiment consisted of four tillage treatments: rotary tillage with crop straw input (RT), conventional tillage with crop straw input (CT), no-tillage with crop straw retention (NT), and rotary tillage with all crop straw removed as a control (RTO). The results indicated that the rhizosphere soil N transformation rate in paddy field under the NT and RTO treatments was significantly decreased compared to RT and CT treatments. In comparison to the NT and RTO treatments, soil protease, urease, β-glucosaminidase, and arginase activities were significantly improved by the CT treatment, as were abundances of soil sub, npr, and chiA with CT and RT treatments. Moreover, the overall diversity of soil bacterial communities in NT and RTO treatments was significantly lower than that in RT and CT treatments. Soil chitinolytic and bacterial ureolytic communities were also obviously changed under a combination of tillage and crop straw input practices.

• 한국환경농학회지
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• 제36권3호
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• pp.141-146
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• 2017

BACKGROUND: Phosphorus(P) is a vital factor for rice but excess input of phosphorus fertilizer can cause environmental risk and waste of fertilizer resources. We studied to assess the change of available phosphate, P balance, critical concentration of available phosphate under a rice single system. METHODS AND RESULTS: The changes of available phosphate of paddy soil were examined from long-term fertilization experiment which was started in 1954 at the National Academy of Agricultural Science. The treatments were no phosphate fertilization(No fert., and N), phosphate fertilization(NPK, NPKC, and NPKCLS). The available phosphorus concentrations in treatments without phosphate fertilizer (No fert. and N) were decreased continuously. But, after 47 years, available phosphate content in phosphate fertilizer treatment (NPK, NPKC, and NPKCLS) reached at the highest ($245{\sim}331mg\;kg^{-1}$), showing a tendency to decrease afterward. The mean annual P field balance in these treatments (NPK, NPKC, and NPKCLS) had positive values that varied from 16.6 to $17.5kg\;ha^{-1}year^{-1}$, and ratio of residual P were increased. These showed that phosphate fertilizer in soil were converted into the form of residual phosphorus which was not easily extracted by available phosphate extractant. Also, It was estimated that the critical value of available phosphate for rice cultivation was $120mg\;kg^{-1}$ using Cate-Nelson equation. CONCLUSION: We concluded that no more phosphate fertilizer should be applied in rice single system if soil available phosphate is higher than the critical P value.

• 유기물자원화
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• 제28권3호
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• pp.37-44
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• 2020

국가정책사업인 유기질비료 지원사업은 1999년부터 시작되었고, 유기질비료의 과다 시용은 시설재배지의 양분집적을 초래했다. 시설상추 재배시 안정적인수량 확보와 과다 시비로 인한 환경오염을 예방하기 위해 유기복합비료의 적정 추천량 기준을 설정하고자 시험하였다. 유기복합비료의 무기질 질소 기비량의 대체비율은 토양검정 질소 기비량(8.6 kg 10a^-1)을 기준으로 100%에서 작물수량이 높았다. 토양의 질산태질소와 전기전도도도 무기질비료 처리구보다 낮은 함량을 나타냈다. 또한, 기비량 100%를 유기복합비료로 대체한 경우에 질소이용율은 23%로 무기질비료 처리구와 유사하게 나타났다. 이러한 결과로부터 상추의 수량을 증가시키고 토양 중에 투입된 비료성분의 토양 잔류 정도를 최소화하는 관점에서는 유기복합비료를 무기질 질소 기비량의 100%를 대체하는 것이 타당하다고 판단된다.

• Journal of Ecology and Environment
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• 제35권4호
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• pp.307-311
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• 2012

This study was conducted to evaluate the dynamics of soil respiration (total soil and heterotrophic respiration) following fertilizer application in red pine forests. Fertilizer (N:P:K = 113:150:37 kg/ha), which reflects current practices in Korean forest, was applied in April 2011, and total soil and heterotrophic respiration rates were monitored from April 2011 to March 2012. Monthly variation of total soil and heterotrophic respiration rates were similar between the fertilizer and control treatments, as soil temperature was the dominant factor controlling the both rates. Total soil respiration rates during the study period were not significantly different between the fertilizer (0.504 g $CO_2\;m^{-2}\;h^{-1}$) and control (0.501 g $CO_2\;m^{-2}\;h^{-1}$) treatments. However, the proportion of heterotrophic respiration was higher in the fertilizer (78% of total soil respiration rates) than in the control (62% of total soil respiration rates) treatments. These results suggest that current fertilizer practices in Korea forest soil do not substantially affect total soil respiration rates.

• 한국토양비료학회지
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• 제49권6호
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• pp.789-794
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• 2016

Continuous excessive application of phosphorus (P) fertilizer and manure in plastic film house soils can lead to an accumulation of P in soils. The understanding of P sorption by soils is important for fertilizer management. In this study, 9 samples were collected for acidic and calcareous soils as non-cultivated soil and plastic film house soils as cultivated soil Phosphorus sorption data of acidic soils fit the Langmuir equations, Freundlich equations in calcareous and plastic film house soils. In calcareous and plastic film house soils, the slope of isotherm adsorption changed abruptly, which could be caused P precipitation with $CaCO_3$. The calculated Langmuir adsorption maximum ($S_{max}$) varied from 217 to 1,250, 139 to 1,429, and $714mg\;kg^{-1}$ for acidic soils, calcareous soils, and plastic film house soils with low available phosphate concentration, respectively. From this result, maximum P adsorption by the Langmuir equation could be regarded as threshold of P concentration to induce the phosphate precipitation in soil. Phosphate-sorption values estimated from one-point isotherm for acidic and calcareous soils as non-cultivated soils were comparable with the $S_{max}$ values calculated from the Langmuir isotherm.

• 한국토양비료학회지
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• 제48권4호
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• pp.233-239
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• 2015

Monitoring of soil fertility and crop productivity in long-term application of fertilizers is necessary to use fertilizers efficiently. This study was conducted to investigate effects of continuous application of lime for rice cultivation from 1969 to 2014. The treatments were no lime treatments (N, NPK, NPKC, and NPKS) and lime treatments (N+L, NPK+L, NPKC+L, and NPKS+L). The application of lime in addition to N, NPK, and NPKC tended to increase pH, exchangeable Ca, and available $SiO_2$. The input of mean annual $1,170Mg\;ha^{-1}yr^{-1}$ of lime increased pH $0.0042yr^{-1}$, $0.0062yr^{-1}$, $0.0127yr^{-1}$, and $0.0041yr^{-1}$ in lime treatments (N+L, NPK+L, NPKS+L, and NPKC+L) compared with no treatments (N, NPK, NPKS, and NPKC), respectively. The mean annual Ca field balance varied from 169 to $561kg\;ha^{-1}yr^{-1}$in no treatments, from 871 to $1,263kg\;ha^{-1}yr^{-1}$ in lime treatments, indicating that Ca was accumulated in the soils. The mean annual Ca field balance in silicate fertilizer treatments (NPKS, NPKS+L) were higher than that of other treatments because silicate fertilizer included Ca component. Grain yield of rice had no significant differences between no lime treatments and lime treatments. Thus the application of lime led to changes in soil chemical properties but had no impact on the production of rice.

• 한국토양비료학회지
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• 제49권4호
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• pp.388-392
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• 2016

The objectives of fertilizer recommendation are to prevent the application of excessive fertilization and to produce target yields. Also, optimal fertilization is important because crop quality can be influenced by fertilization. In this study, yields and fertilizer use efficiency of Taro (Colocasia esculenta Schott) were evaluated in different level of NPK fertilization. N, P and K fertilizer application rates were 5 levels (0, 50, 100, 150, 200%) by practical fertilization ($N-P_2O_5-K_2O=180-100-150kg\;ha^{-1}$), respectively. In the N treatment, the yields of Taro tuber were about $33Mg\;ha^{-1}$ from 90 to $360kg\;ha^{-1}$ N fertilization. However, the ratio of tuber to total biomass decreased with increasing N fertilization rate. In the P and K treatments, yields of Taro tuber were the highest at $150kg\;ha^{-1}$ fertilization. Fertilizer use efficiency was decreased by increase of N and K fertilization. Crude protein of Taro tuber was the highest at practical fertilization. Sucrose content of tuber was influenced by phosphate application.

• 한국토양비료학회지
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• 제48권6호
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• pp.628-633
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• 2015

It is necessary to assess soil physical properties and crop growth treated by compaction to establish the soil management standard. This study evaluated the bulk density, strength and crop growth after subsoil compaction for sandy loam and loam on the field in Suwon, Korea. The treatments were compaction and deep tillage. Sandy loam and loam were classified to coarse soil and fine soil, respectively, depending on clay contents. In coarse soil, bulk density of compacted plot was 8~17% greater than control and deep tilled plot. The root growth was worse in compacted plot compared with control. In fine soil, plow pan was not observed in deep tilled plot with 5~19% smaller bulk density than compacted plot and control. Deep tillage improved the crop growth. The soil physical properties by compaction were dependent on clay content and crop growth limit depended on the traffic driving.

• 한국토양비료학회지
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• 제47권6호
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• pp.553-557
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• 2014

The steady increase in livestock industry has greatly required the stable production of food and forage crops. As an alternative, rice-forage cropping system has been attempted in several southern areas. The present study was performed to understand whether an application of cattle-manure compost affects soil chemical properties and crop productivity in rice-forage cropping system, rice ${\rightarrow}$ summer oat ${\rightarrow}$ rye, in Jangheong county, south Jeolla province from 2013 to 2014. Treatments was composed of control (no compost), CM1 (compost application before rice transplanting), and CM2 (two-times compost application, before rice transplanting and after rice harvest), and inorganic fertilizers (N, P, and K) were equally dressed in all plots. Yields of rice were not significantly different between treatments, however, oat production was 1.25-fold higher in CM1 and CM2. Nutrient uptake amounts of rye were higher in CM2 than CM1 and control. Total nitrogen in soil was maintained stable level during crop cultivation. And soil organic matter contents in all treatments were increased by crop residue. Available P_2O_5$ and exchangeable K were increased by cattle manure application. Therefore, it suggested that the amount of nutrient by forage crop residue should be considered in rice-forage multiple cultivation.

• 한국토양비료학회지
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• 제48권3호
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• pp.189-193
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• 2015

Bad drainage problems from paddy fields adjacent to roads are caused by higher constructed roads which change topography of paddy fields to concave topography and artificial pan to prevent road erosion when road constructions are occurred. This study investigated effects of topography changes on soils by road constructions. Soil samples were investigated by physico-chemical analyses and micromorphology analyses from representative soil profile of Sachon series and soil samples. The characteristics of Sachon series that were adjacent to roads were fewer redoximorphic features (RMF) and increase in grey layers than the original Sachon series. The characteristics of Yecheon Series were shown from Jeollanamdo - Suncheon > Chungchungnamdo - Cheonan > Gangwondo - Wonju. Mosaic speckles were shown from micromorphological analyses because of repeat of shrink and expansion by wetting and drying. The location of graying in soil clods were found from coarse stone blocks to fine stone blocks and color changes of composed particles were also found.