• Applied Biological Chemistry
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• 제25권3호
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• pp.150-154
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• 1982

중질소요소(重窒素尿素)를 사용(使用) 3품종(品種)에 대(對)한 분시시험(分施試驗)을 폿드에서 수행하였다. 2회분시(回分施)는 4회분시(回分施)보다 통일계(統一系)에 월등히 좋았다. 시비효율(Fe), 이용율(利用率) 및 흡수시비질소효율(吸收施肥窒素效率)(Ef)은 4회분시(回分施)보다 2회분시(回分施)에서 월등히 컸다. Fe의 순위는 Ef의 순위와 같았다. 수량(收量)과 중질소과잉율(重素窒過利率)은 통일계(統一系)가 생육초기(生育初期)에 시용질소(施用窒素)를 많이 흡수(吸收)하여 후기(後期)에 상당히 재전류(再轉流)시킴을 나타내었다. 흡수시비질소(吸收施肥窒素)에 대(對)한 토양질소흡수증가량(土壤窒素吸收增加量) $({\Delta}Ns/Nf)$은 시비(施肥)로 인(因)한 토양질소이용율(土壤窒素利用率)의 지표(指標)가 될 수 있다.

• 한국초지조사료학회지
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• 제14권2호
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• pp.88-92
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• 1994

본 시험은 석회(0, 250, 1,000kg/10a)와 인산(0, 17 및 34kg/10a)t용이 alfalfa의 생장 및 질소고정에 미치는 영향을 구명하기 위하여 전남대학교 농과대학내 온실에서 pot로 수행되었는데 그 결과를 요약하면 다음과 같다. 실험기간동안 alfalfa의 지상부와 지하부의 건물중, 근류중량 및 acetylene환원력은 pH6.2인 토양에서 석회시용 효과가 인정되지 않았지만, 인산시용 효과는 인정되었다(p<0.05). 파종 후 7주에서 alfalfa의 부위별 전질소 함량은 석회시용구가 무시용구보다 증가하였으나 석회시용 수준간에는 차이가 나타나지 않았으며 인산시용 효과도 나타나지 않았다. 파종 후 12주에서 alfalfa의 부위별 전질소 함량은 석회시용구와 무시용구사이에 차이가 나타나지 않았고, 인산시용구는 무시용구보다 낮아지는 경향을 보였다(p<0.05). 이상의 결과를 종합해볼 때, pH6.2인 약산성 토양에서 석회 10a당 250kg시용구아ㅗ 인산 34kg시용구가 alfalfa의 생장 및 질소 고정에 유리하게 작용하였다.

• 한국토양비료학회지
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• 제50권6호
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• pp.574-587
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• 2017

Excessive application of nitrogen (N) fertilizer to support switchgrass growth for bioenergy production may cause adverse environmental effects. The objective of this study was to determine optimum N application rate to increase biomass yield of switchgrass and to reduce adverse environmental effects related to N. Switchgrass was planted in May 2008 and biomass yield, N uses of switchgrass, nitrate ($NO_3$) leaching, and nitrous oxide ($N_2O$) emission were evaluated from 2010 through 2011. Total N removal significantly increased with N rate despite the fact that yield did not increased with above $56kg\;N\;ha^{-1}$ of N rate. Apparent nitrogen recoveries were 4.81 and 5.48% at 56 and $112kg\;N\;ha^{-1}$ of N rate, respectively. Nitrogen use efficiency decreased into half with increasing N rate from 56 to $112kg\;N\;ha^{-1}$. Nitrate leaching and $N_2O$ emission were related to N use of switchgrass. There was no significant difference of cumulative $NO_3$ leaching between 0 and $56kg\;N\;ha^{-1}$ but, it significantly increased at $112kg\;N\;ha^{-1}$. There was no significant difference of cumulative $N_2O$ emission among N rates in crest, but it significantly increased at $112kg\;N\;ha^{-1}$ in toe. Excessive N application rate (above $56kg\;N\;ha^{-1}$) beyond plant requirement could accelerate $NO_3$ leaching and $N_2O$ emission in switchgrass field. Overall, $56kg\;N\;ha^{-1}$ might be optimum N application rate in reducing economic waste on N fertilizer and adverse environmental impacts.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.232-241
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• 2012

We investigated the relationship between vegetation type and soil carbon dynamics in even-aged alder (Alnus hirsuta) and Korean pine (Pinus koraiensis) plantations in central Korea. Both forests were located on the same soil parent material and occupied similar topographic positions. Soil $CO_2$ efflux in the two plantations was determined using a dynamic chamber method accompanied by measurements of soil moisture content and temperature. Mean soil temperature was similar in the two plantations, but mean soil water content was significantly higher in the alder plantation than in the pine plantation. In both plantations, seasonal patterns in soil $CO_2$ efflux exhibited pronounced variation that corresponded to soil temperature. Soil water content did not affect the seasonal variation in soil $CO_2$ efflux. However, in summer, when soil temperature was above $17^{\circ}C$, soil $CO_2$ efflux increased linearly with soil water content in the alder plantation. Estimated $Q_{10}$ was 3.3 for the alder plantation and 2.7 for the pine plantation. Mean soil respiration during the measurement period in the alder plantation was 0.43 g $CO_2\;m^{-2}\;h^{-1}$, which was 1.3 times higher than in the pine plantation (0.33 g $CO_2\;m^{-2}\;h^{-1}$). Higher soil $CO_2$ efflux in the alder plantation might be related to nitrogen availability, particularly the concentration of $NO_3{^-}$, which was measured using the ion-exchange resin bag method.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1688-1696
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• 2020

Soil physical and chemical characteristics, soil potential denitrification rates (PDR), community composition and nirK-, nirS- and nosZ-encoding denitrifiers were studied by using MiSeq sequencing, quantitative polymerase chain reaction (qPCR), and terminal restriction fragment polymorphism (T-RFLP) technologies base on short-term (5-year) tillage field experiment. The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue retention (NT), and rotary tillage with crop residue removed as control (RTO). The results indicated that soil organic carbon, total nitrogen and NH₄⁺-N contents were increased with CT, RT and NT treatments. Compared with RTO treatment, the copies number of nirK, nirS and nosZ in paddy soil with CT, RT and NT treatments were significantly increased. The principal coordinate analysis indicated that tillage management and crop residue returning management were the most and the second important factors for the change of denitrifying bacteria community, respectively. Meanwhile, this study indicated that activity and community composition of denitrifiers with CT, RT and NT treatments were increased, compared with RTO treatment. This result showed that nirK, nirS and nosZ-type denitrifiers communities in crop residue applied soil had higher species diversity compared with crop residue removed soil, and denitrifying bacteria community composition were dominated by Gammaproteobacteria, Deltaproteobacteria, and Betaproteobacteria. Therefore, it is a beneficial practice to increase soil PDR level, abundance and community composition of nitrogen-functional soil microorganism by combined application of tillage with crop residue management.

• 한국토양비료학회지
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• 제49권1호
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• pp.7-11
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• 2016

Winter crops have been recognized as an alternative to soil management for fertility and crop productivity in paddy soil. Recently, rape has been produced at winter season and there is little research results on reduction of N fertilizer by adding rape residues for rice cultivation. In this study, we investigated the productivity and quality of rice by applying with 0, 27, 63, $90kg\;ha^{-1}$ of N fertilizer after input of rape residues into soil for two years. The highest yield of rice was average $4.68Mg\;ha^{-1}$ at the treatment applied with the $90kg\;N\;ha^{-1}$ with rape residue. It was reduced to N rate from 31.6 to $43.2kg\;N\;ha^{-1}$ in comparison to $4.53Mg\;ha^{-1}$ of maximum yield in treatment added $90kg\;N\;ha^{-1}$ with rape. Amylose content in rice was similar among treatments with/without rape residue, but protein content was lower in treatment with rape residue than in those without rape residue. In conclusion, input of rape residue in rice cultivation could be alternative to reduction of N fertilization and improvement of quality by adjusting rice productivity in paddy soil under cropping system.

• 한국초지조사료학회지
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• 제18권1호
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• pp.43-48
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• 1998

No-tillage silage corn with legume hairy vetch(Vicia villosa Roth, HV) has renewed interest in supply of mineral N, soil erosion control at sloping land and weed control by cover of HV killed. This study was conducted to monitor concentration of soil mineral N ($NO_3^-$ -N + $NH_4^+$-N) and to find out variation of growth, yield and N uptake of silage corn according to quantity of HV cover; HV-removed, 1X-HV, 2X-HV at field of Crop Experiment Station in 1996. HV groM in early spring decreased the mineral N of soil depth 7.5 -22cm before corn seeding. But, killed HV cover increased the concentration of soil mineral N at surface soil (0-7.5cm) up to 45.4mglkg at early growth stage of corn. Dry matter(Dh4) of corn at harvest was lower in W-removed than in Okg FNlha. But DM and N uptake of corn at harvest were increased by quantity of HV-cover increasing liom HV-removed to 2X-HV. Hairy vetch could substitute N fertilizer for silage corn by N mineralized h m HV killed, but reduced early growth and N uptake of corn before silk by reducing soil mineral N of plow layer.

• 원예과학기술지
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• 제17권6호
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• pp.753-754
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• 1999

화학비료의 시용은 토양의 산성화를 가중시키고 포도의 품질을 저하시키고 있다. 본 실험의 결과 퇴비의 시용은 포도 뿌리로 흡수되는 질소량을 낮추어 주며 토양질소 함량, 토양 pH, 토양 유기물함량, 세근의 발생량을 높여 주었다. 장초전정은 포도나무 생육을 감소시켰으며, 특히 웨이크만식 수형의 'Campbell Early'에서 장초전정은 단초전정보다 생육감소가 심해 자체 수형유지가 곤란하였다. 본 실험결과 '캠벨 얼리', '거봉', '쉐리단' 포도원의 퇴비시용은 수체생육을 감소시켰으나 토양환경을 개선함과 동시에 근군분포의 표면화와 세근의 발달을 증가시켰다.

• Journal of Plant Biology
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• 제13권3호
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• pp.25-31
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• 1970

The ratio of occurrence of azalea (Rhododendron mucromultum T.) was determined on the north and south facing slopes on a mountain in Koyang county, Kyungi Province. Data was actually recorded at the eight aspects facing N, NE, E, SE, S, SW, W and NW on the mountain. In each of the eight aspects, six 10m transect tapes were placed in parallel directly down the slope, each 1m apart, and fifty 1$m^2$ quadrats were constructed between them. Frequency of the azalea in each of these quadrats was determined by counting the central stumps of the bushes Soil samples were also taken from pits dug in each plot to use for determination of the following: Soil pH, soil moisture loss on ignition, total nitrogen, and available phosphorus. The occurrence rate of azalea on the northern slop e was found to be for higher on the northern slope than on the southern slope. The abundance of azalea on the northern slope was found to be partially correlated with soil moisture(r=0.93; 0.01>p) and the amount of humus in the soil (r=0.04;0.01>p). The content of total nitrogen, soil PH, and available phosphorus in the soil, however, were found to have no evident relationship with the abundance of azalea. The conditions for growth in the species of azalea Rhododendron mucronulatum T'. were generally found to be more favorable on the northern slope.

• 한국토양비료학회지
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• 제25권3호
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• pp.275-280
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• 1992

숙전(熟田)에서 알팔파 재배시(裁培時) 질소(窒素)를 무시용(無施用)과 8kg/10a시용(施用) 두 조건으로 하고 근류균(根瘤菌) R. meliloti를 무접종(無接種)과 파종시(播種時)의 1회접종(回接種), 그리고 초지조성후(草地造成後) 매년접종법(每年接種法)으로 처리하였을 때 토양내 R. meliloti밀도(密度)와 건초수량(乾草收量) 변화를 3년간 조사한 결과(結果)는 다음과 같았다. 1. R. meliloti의 밀도(密度)는 질소무시용조건(窒素無施用條件)에서 시험 1년차에 크게 증가하여 시험 2년차까지 질소(窒素) 8kg/10a시용조건(施用條件)보다 높았으나(접종구(接種區) 평균(平均) 1년차:33%, 2년차:17%) 3년차에는 반대로 질소시용조건(窒素施用條件)에서 더 (접종구(接種區) 평균(平均) 3%) 높았다. 근류균(根瘤菌)의 접종(接種) 방법별(方法別)로는 매년접종법(每年接種法)(최고(最高) $2.0{\times}10^4cell/g.soil$)이 우수하였고, 계절에 따라서는 월동(越冬)으로 균주밀도(菌株密度)가 감소되었으나 하절기(夏節期) 이후 회복되는 경향을 보였다. 2. 알팔파 수량(收量)은 질소(窒素) 8kg/10시용효과(施用效果) 보다는 근류균(根瘤菌) 밀도(密度)의 영향을 많이 받으면서 처리별(處理別) 근류균(根瘤菌)의 밀도(密度)와 고도(高度)의 유의적(有意的)인 상관관계(相關關係)(Y=0.36+0.287X, $r^2=0.58^{**}$)를 보였다. 그리고 시험기간 근류균(根瘤菌) 접종(接種)에 의한 수량증가(收量增加)는 질소무시용(窒素無施用)과 시용조건(施用條件)에서 각각 접종잔효구(接種殘效區)의 경우 1년차 66, 10% : 2년차 13, 20% : 3년차 19, 13%였고 매년접중구(每年接種區)는 1년차 66, 10% : 2년차 30, 20% : 3년차 35, 36%였다. 3. 숙전(熟田)에서 알팔파 근류균(根瘤菌) 접종효과(接種效果)는 파종시(播種時) 1회접종(回接種)으로도 3년이상 증수(增收)되나 절대수량(絶對收量)을 높이기 위해서는 매년(每年) 접종(接種)하는 것이 더 바람직하였다.