Sensing Nitrate and Potassium Ions in Soil Extracts Using Ion-Selective Electrodes

Kim, H.J.,Sudduth Kenneth A.,Hummel John W. Korean Society for Agricultural Machinery 2006 바이오시스템공학 Vol.31 No.6

Automated sensing of soil macronutrients would allow more efficient mapping of soil nutrient spatial variability for variable-rate nutrient management. The capabilities of ion-selective electrodes for sensing macronutrients in soil extracts can be affected by the presence of other ions in the soil itself as well as by high concentrations of ions in soil extractants. Adoption of automated, on-the-go sensing of soil nutrients would be enhanced if a single extracting solution could be used for the concurrent extraction of multiple soil macronutrients. This paper reports on the ability of the Kelowna extractant to extract macronutrients (N, P, and K) from US Corn Belt soils and whether previously developed PVC-based nitrate and potassium ion-selective electrodes could determine the nitrate and potassium concentrations in soil extracts obtained using the Kelowna extractant. The extraction efficiencies of nitrate-N and phosphorus obtained with the Kelowna solution for seven US Corn Belt soils were comparable to those obtained with IM KCI and Mehlich III solutions when measured with automated ion and ICP analyzers, respectively. However, the potassium levels extracted with the Kelowna extractant were, on average, 42% less than those obtained with the Mehlich III solution. Nevertheless, it was expected that Kelowna could extract proportional amounts of potassium ion due to a strong linear relationship ($r^2$ = 0.96). Use of the PVC-based nitrate and potassium ion-selective electrodes proved to be feasible in measuring nitrate-N and potassium ions in Kelowna - soil extracts with almost 1 : 1 relationships and high coefficients of determination ($r^2$ > 0.9) between the levels of nitrate-N and potassium obtained with the ion-selective electrodes and standard analytical instruments.

토양용액 채취를 위한 토성별 한계수분함량 설정

이창훈(Chang Hoon Lee),김명숙(Myung Sook Kim),공명석(Myung Seok Kong),김유학(Yoo Hak Kim),오택근(Taek-Keun Oh),강성수(Seong Soo Kang) 충남대학교 농업과학연구소 2014 농업과학연구 Vol.41 No.4

Soil moisture is an important factor for the availability and circulation of nutrients in arable soil. The purpose of this study was to set thresholds moisture content on soil nitrate concentration in the solution for real-time diagnosis. Sandy loam, silt loam, and sandy loam was filled with 1.2 g cm<SUP>-3</SUP> at Wagner pots, 0, 100, and 200 mg L<SUP>-1</SUP> of KNO₃ was saturated. Nitrate in standard solution was recovered about 95% by passing the porous cup. Nitrate concentrations in sampling of soil solution were examined by using a porous cup. The soil solution was higher in accordance with sandy loam> silt loam> clay loam, limited water filled pore space for sampling soil solution was 33.7, 56.4, and 62.2%, respectively. Nitrate concentration in the soil solution was negligible at sandy loam and silt loam during sampling periods, which was decreased about 50~82% in clay loam compared to the initial NO3-N concentration in the saturated KNO₃ solution. Over limitation of soil solution sampling, soil EC and NO3-N content were increased with the saturated NO3-N concentration, regardless of soil texture (p <0.05). Conclusively, soil solution by using a porous cup was possible, regardless of the soil texture, which was useful for the diagnosis in nitrate concentration of soil solution. However, because nitrate concentration of soil solution in a clay loam changes, it was necessary for careful attention in order to take advantage for the real-time diagnosis of nitrogen management in soil.

토양용액 채취를 위한 토성별 한계수분함량 설정

이창훈(Chang Hoon Lee),김명숙(Myung Sook Kim),공명석(Myung Seok Kong),김유학(Yoo Hak Kim),오택근(Taek-Keun Oh),강성수(Seong Soo Kang) 충남대학교 농업과학연구소 2014 Korean Journal of Agricultural Science Vol.41 No.4

Soil moisture is an important factor for the availability and circulation of nutrients in arable soil. The purpose of this study was to set thresholds moisture content on soil nitrate concentration in the solution for real-time diagnosis. Sandy loam, silt loam, and sandy loam was filled with 1.2 g cm<SUP>-3</SUP> at Wagner pots, 0, 100, and 200 mg L<SUP>-1</SUP> of KNO₃ was saturated. Nitrate in standard solution was recovered about 95% by passing the porous cup. Nitrate concentrations in sampling of soil solution were examined by using a porous cup. The soil solution was higher in accordance with sandy loam> silt loam> clay loam, limited water filled pore space for sampling soil solution was 33.7, 56.4, and 62.2%, respectively. Nitrate concentration in the soil solution was negligible at sandy loam and silt loam during sampling periods, which was decreased about 50~82% in clay loam compared to the initial NO<SUB>3-</SUB>N concentration in the saturated KNO₃ solution. Over limitation of soil solution sampling, soil EC and NO<SUB>3-</SUB>N content were increased with the saturated NO<SUB>3-</SUB>N concentration, regardless of soil texture (p <0.05). Conclusively, soil solution by using a porous cup was possible, regardless of the soil texture, which was useful for the diagnosis in nitrate concentration of soil solution. However, because nitrate concentration of soil solution in a clay loam changes, it was necessary for careful attention in order to take advantage for the real-time diagnosis of nitrogen management in soil.

Estimation of Nitrogen Fertilizer Recommendations for cucumber by Soil Incorporation of Rye Based on Soil Nitrate Nitrogen Content

임태준,박진면,이성은 한국토양비료학회 2018 한국토양비료학회지 Vol.51 No.3

In this study, we estimated the appropriate nitrogen (N) recommendations of cucumber by evaluating the effects of soil incorporation of rye (Secale cereal L.) as a green manure crops on the growth and yield of cucumber under the greenhouse condition showing two different soil nitrate N levels. One, soil nitrate-N content before the experiment was 60 mg kg-1, carried out in 2012 and the other showing a 227 mg kg-1 level was conducted in 2013. Six different N treatments were used as follows: No N fertilizer, rye, rye with urea 0.5N, 0.75N, and 1.0N, and urea 1.0N. The amount of N supply from soil incorporation of rye was 146 kg ha-1 in 2012 and 107 kg ha-1 in 2013. When soil nitrate N content before the experiment was 60 mg kg-1, the growth and yield of cucumber did not differ between the rye + urea 0.5N and the urea 1.0N, which can reduce 50% of N fertilizer recommendation. In case of soil nitrate N content before the experiment was 227 mg kg-1 or beyond, no N fertilization can be recommended because there were no significant differences in the growth and yield of cucumber among all treatments including the rye. Lastly, when soil nitrate N content before the experiment was within range of 227 - 60 mg kg-1, N recommendations can be calculated through the equation Y = -3.34X + 227 (X: % of N recommendations, Y: soil nitrate N content). However, further studies on the relationship between soil nitrate N content and yield of cucumber are required.

Estimation of Nitrogen Fertilizer Recommendations for cucumber by Soil Incorporation of Rye Based on Soil Nitrate Nitrogen Content

Tae-Jun Lim,Jin-Myeon Park,Seong-Eun Lee 한국토양비료학회 2018 한국토양비료학회지 Vol.51 No.3

In this study, we estimated the appropriate nitrogen (N) recommendations of cucumber by evaluating the effects of soil incorporation of rye (Secale cereal L.) as a green manure crops on the growth and yield of cucumber under the greenhouse condition showing two different soil nitrate N levels. One, soil nitrate-N content before the experiment was 60 mg kg<SUP>-1</SUP>, carried out in 2012 and the other showing a 227 mg kg<SUP>-1</SUP> level was conducted in 2013. Six different N treatments were used as follows: No N fertilizer, rye, rye with urea 0.5 N, 0.75 N, and 1.0 N, and urea 1.0 N. The amount of N supply from soil incorporation of rye was 146 kg ha<SUP>-1</SUP> in 2012 and 107 kg ha<SUP>-1</SUP> in 2013. When soil nitrate N content before the experiment was 60 mg kg<SUP>-1</SUP>, the growth and yield of cucumber did not differ between the rye + urea 0.5 N and the urea 1.0 N, which can reduce 50% of N fertilizer recommendation. In case of soil nitrate N content before the experiment was 227 mg kg<SUP>-1</SUP> or beyond, no N fertilization can be recommended because there were no significant differences in the growth and yield of cucumber among all treatments including the rye. Lastly, when soil nitrate N content before the experiment was within range of 227 - 60 mg kg<SUP>-1</SUP>, N recommendations can be calculated through the equation Y = -3.34X + 227 (X: % of N recommendations, Y: soil nitrate N content). However, further studies on the relationship between soil nitrate N content and yield of cucumber are required.

Originals : Influence of Sewage Sludge Application on Soil Nitrate Distribution in a Clay Soil

이상모 ( Sang Mo Lee ) 한국환경농학회 2003 한국환경농학회지 Vol.22 No.1

Nitrate contamination in the aquatic systems is the primary indicator of poor agricultural management. The influence of sewage sludge application rates (0, 10, 25, 50 and 100 dry Mg/ha) on distribution of nitrate originating from the sewage sludge in soil profiles was investigated. Soil profile monitoring of nitrate was carded out with a Lakeland clay soil in 1997. Irrespectively of the sewage sludge application rates up to 50 dry Mg/ha, the concentration of NO₃-N at the 120 cm depth was below 10 mg/kg and the difference due to the amount of sewage sludge application was negligible at this depth. There was virtually no NO₃-N below 120 cm depth and this was confirmed by a deep sampling up to 300 cm depth. Most of the nitrate remained in the surface 60 cm of the soil. Below 120 cm depth, nitrate concentration was very low because of the deniteifcation even at high sewage sludge rate of 100 dry Mg/ha. The NO₃-N concentrations in the soft fluctuated over the growing season due to plant uptake and denitrificallon. The risk of groundwater contamination by nitrate from sewage sludge application up to high rate of 100 dry Mg/ha was very low in a wheat grown clay soil with high water table (< 3 m).

Bacillus sp. PCE3 균주에 의한 질산이온 흡수 특성

윤영배 ( Yeong Bae Yun ),박수진 ( Soo Jin Park ),한민우 ( Min Woo Han ),김영기 ( Young Kee Kim ) 한국응용생명화학회 2013 Journal of Applied Biological Chemistry (J. Appl. Vol.56 No.4

Nitrate is one of the major nutrients in plants, and nitrate fertilizer often overused for the high yields of crops. Nitrate deposit in soil became one of the major reasons causing salt stress. Specially, salt stress is a serious problem in the soils of plastic film or glass houses. In this study, six microorganisms have been isolated from the wet soils near the disposals of livestock farms and their nitrate uptake activities were investigated. These bacteria were able to remove nitrate as high as 1,000?3,000 ppm (10?50 mM). The strain PCE3 showed the highest nitrate uptake activity and it removed more than 3,700 ppm. In order to identify these bacteria, genes of 16S rRNA were sequenced and analyzed. Phylogenetic trees were constructed with the neighbor-joining methods. Among these bacteria, strain PCE3 was identified as Bacillus species. When the growth and nitrate uptake activities were measured, both were maximal at 37oC and optimal pH was pH 7?9. Bacillus sp. PCE3 removed nitrate up to 40?60 mM (2,500?3,700 ppm) depending on the nitrate concentration in media. Therefore, Bacillus sp. PCE3 can be a good candidate for the microbial remediation of nitrate-deposited soils in glass and plastic film houses.

염기성 pH에서 Enterobacter amnigenus GG0461의 질산이온 흡수증가

최태근,김성태,한민우,김영기 한국응용생명화학회 2008 Journal of Applied Biological Chemistry (J. Appl. Vol.51 No.1

Salt accumulation in soils of greenhouse due to the massive application of nitrogen fertilizers causes salt stress on the various crops, a serious problem in domestic agriculture. Since the majority of the salinity is nitrate, the excess nitrate should be removed; therefore, a bacterial strain having high capacity of nitrate uptake and identified as Enterobacter amnigenus GG0461 was isolated from the soils of greenhouse. Optimum conditions for the bacterial growth and nitrate uptake were investigated. GG0461 was able to grow without nitrate; however, nitrate facilitated the growth. The rate of nitrate uptake increased at alkaline pH and both growth and nitrate uptake were maximal at pH 8-9. When the initial pH of culture medium was increased to pH 8 or 9, it was decreased to neutral upon bacterial growth and nitrate uptake. These results imply that the major factor mediating bacterial nitrate uptake is a nitrate/proton antiporter. The fact was supported by the effect of nitrate addition in the absence of nitrate, since the addition of nitrate greatly increased the nitrate uptake and rapidly decreased pH of media. 질소비료의 과량 시용에 따른 시설원예지 토양 중 염류집적은 다양한 작물에 염류장애를 유발하여 국내농업에 심각한 문제가 되고 있다. 염류의 주성분은 질산염으로 필요이상의 질산 이온을 제거하기 위하여 질산이온 흡수력이 크며, Enterobacter amnigenus GG0461로 동정된 토양세균을 시설원예 토양에서 분리하였다. 이 균주의 최적 생육 및 질산이온 흡수력을 조사하였을 때, GG0461 균주는 질산이온이 없는 조건에서 생육이 가능하나, 질산이온이 존재할 때 생육이 크게 촉진되었다. 또한, 염기성 조건에서 질산이온 흡수율이 증가하였으며, 성장과 질산이온 흡수 모두 pH 8-9에서 최대로 나타났다. 배지의 초기 pH를 8과 9로 조정하였을 때, 균주에 의하여 질산이온이 흡수 됨에 따라 배지의 pH는 중성으로 감소하였다. 이러한 결과는 질산이온 흡수를 위한 주된 인자가 nitrate/proton antiporter임을 의미한다. 이것은 질산이온이 없는 조건에서 질산이온의 첨가 효과인 질산이온 흡수의 급격한 증가와 빠른 배지의 pH 감소 사실로도 확인되었다.

Emission of NO2 Gas Causing Damage to Plants in an Acid Soil under Conditions Favorable for Denitrification

서선영,변일수,이용세,정종배 한국토양비료학회 2013 한국토양비료학회지 Vol.46 No.4

Nitrogen dioxide (NO2) gas damage on vegetable crops commonly occurs in plastic film houses where relatively large amounts of NO3- are applied in acid soils. In acid soils, HNO2 can be formed from the NO2- accumulated during denitrification, and NO2 can be evolved from the chemical self-decomposition of HNO2. In this study, NO2 gas production and its detrimental effects on plants were investigated in soils of various conditions to elucidate the mechanisms involved in the gas production. A silty loam soil was amended with NO3- (500 mg N kg-1) and glucose, and pH and moisture of the soil were adjusted respectively to 5.0 and 34.6% water holding capacity (WHC) with 0.01 M phosphate buffer. The soil was placed in a 0.5-L glass jar with strawberry leaf or NO2 gas absorption badge in air space of the jar, and the jar was incubated at 30oC. After 4-5 days of incubation, dark burning was observed along the outside edge of strawberry leaf and NO2 production was confirmed in the air space of jar. However, when the soil was sterilized, NO2 emission was minimal and any visible damage was not found in strawberry leaf. In the soil where water or NO3- content was reduced to 17.3% WHC or 250 mg N kg-1, NO2 production was greatly reduced and toxicity symptom was not found in strawberry leaf. Also in the soil where glucose was not amended, NO2 production was significantly reduced. In soil with pH of 6.5, NO2 was evolved to the level causing damage to strawberry leaf when the soil conditions were favorable for denitrification. However, compared to the soil of pH 5.0, the NO2 production and its damage to plants were much less serious in pH 6.5. Therefore, the production of NO2 damaging plants might be occurred in acid soils when the conditions are favorable for denitrification.

Emission of NO₂ Gas Causing Damage to Plants in an Acid Soil under Conditions Favorable for Denitrification

Suh, Sun-Young,Byeon, Il-Su,Lee, Yong-Se,Chung, Jong-Bae Korean Society of Soil Science and Fertilizer 2013 한국토양비료학회지 Vol.46 No.4

Nitrogen dioxide ($NO_2$) gas damage on vegetable crops commonly occurs in plastic film houses where relatively large amounts of $NO_3{^-}$ are applied in acid soils. In acid soils, $HNO_2$ can be formed from the $NO_2{^-}$ accumulated during denitrification, and $NO_2$ can be evolved from the chemical self-decomposition of $HNO_2$. In this study, $NO_2$ gas production and its detrimental effects on plants were investigated in soils of various conditions to elucidate the mechanisms involved in the gas production. A silty loam soil was amended with $NO_3{^-}$ (500 mg N $kg^{-1}$) and glucose, and pH and moisture of the soil were adjusted respectively to 5.0 and 34.6% water holding capacity (WHC) with 0.01 M phosphate buffer. The soil was placed in a 0.5-L glass jar with strawberry leaf or $NO_2$ gas absorption badge in air space of the jar, and the jar was incubated at $30^{\circ}C$. After 4-5 days of incubation, dark burning was observed along the outside edge of strawberry leaf and $NO_2$ production was confirmed in the air space of jar. However, when the soil was sterilized, $NO_2$ emission was minimal and any visible damage was not found in strawberry leaf. In the soil where water or $NO_3{^-}$ content was reduced to 17.3% WHC or 250 mg N $kg^{-1}$, $NO_2$ production was greatly reduced and toxicity symptom was not found in strawberry leaf. Also in the soil where glucose was not amended, $NO_2$ production was significantly reduced. In soil with pH of 6.5, $NO_2$ was evolved to the level causing damage to strawberry leaf when the soil conditions were favorable for denitrification. However, compared to the soil of pH 5.0, the $NO_2$ production and its damage to plants were much less serious in pH 6.5. Therefore, the production of $NO_2$ damaging plants might be occurred in acid soils when the conditions are favorable for denitrification.