• Korean Journal of Soil Science and Fertilizer
• /
• v.47 no.1
• /
• pp.41-47
• /
• 2014

Agricultural soils surrounding mine areas in South Korea are often contaminated with multiple metals such as Cd, Pb and Zn. It poses potential risks to plants, soil organisms, groundwater, and eventually human health. The aim of this study was to examine the changes in phytoavailability of Cd, Cu, Pb and Zn after application with calcined eggshell (CES; 0, 1, 3, and 5% W/W) in an agricultural soil contaminated by mine tailings. The contents of Cd, Cu, Pb and Zn in soils were 8.79, 65.4, 1602, and $692mgkg^{-1}$ (aqua regia dissolution), respectively. The experiments were conducted with lettuce (Lactuca sativa L. var. longifolia) grown under greenhouse conditions during a 30-d period. $NH_4NO_3$ solution was used to examine the mobile fraction of these metals in soil. The application of CES dramatically increased soil pH and inorganic carbon content in soil due to CaO and $CaCO_3$ of CES. The increased soil pH decreased the mobile fraction of Cd, Pb, Zn: from 3.49 to < $0.01mgkg^{-1}$ for Cd, from 79.4 to $1.75mgkg^{-1}$ for Pb, and from 29.6 to $1.13mgkg^{-1}$ for Zn with increasing treatment of CES from 0 to 5%. In contrast, the mobile fraction of Cu was increased from 0.05 to $3.08mgkg^{-1}$, probably due to the formation of soluble $CuCO_3{^0}$ and Cu-organic complex. This changes in the mobile fraction resulted in a diminished uptake of Cd, Pb and Zn by lettuce and an increased uptake of Cu: from 4.19 to < $0.001mgkg^{-1}$ dry weight (DW) for Cd, from 0.78 to < $0.001mgkg^{-1}$ DW for Pb, and from 133 to $50.0mgkg^{-1}$ DW for Zn and conversely, from 3.79 up to $8.21kg^{-1}$ DW for Cu. The increased contents of Cu in lettuce shoots did not exceed the toxic level of $>25mgkg^{-1}$ DW. The mobile contents of these metals in soils showed a strong relationship with their contents in plant roots and shoots. These results showed that CES effectively reduced the phytoavailability of Cd, Pb, and Zn to lettuce but elevated that of Cu in consequence of the changed binding forms of Cd, Cu, Pb, and Zn in soils. Based on these conclusions, CES can be used as an effective immobilization agent for Cd, Pb and Zn in contaminated soils. However, the CES should be applied in restricted doses due to too high increased pH in soils.

• Korean Journal of Environmental Agriculture
• /
• v.21 no.4
• /
• pp.255-260
• /
• 2002

This study was conducted to evaluate the effect of the proper application level of anaerobic digestion waste water on rice. The waste water was from methane fermentation of pig manure to use as a liquid manure. The mixture treatment of 70% liquid manure and 30% chemical fertilizer (LM 70%+CF 30%) and 100% liquid manure (LM 100%) treatment were higher number of tiller than other treatments at the both tillering and heading stages of rice. The yields of LM 70%+CF 30% and LM 100% treatments were a little higher than that of NPK treatment, but the mixture treatment of 50% liquid manure and 50% chemical fertilizer (LM 50%+CF 50%) was a little lower yield than NPK treatment. The periodic changes of the $NH_4-N$ and $NO_3-N$ contents of the NPK and the LM 50%+CF 50% treatments in paddy soil were a little higher than those of other treatments at the early stage of rice. The $NH_4-N$ contents of NPK and the LM 50%+CF 50% treatments in irrigation water quality were higher than those of other treatments, however there was no difference in $NO_3-N$ content among the treatments. The $NH_4-N$ and $NO_3-N$ contents of non fertilizer treatment in infiltration water quality were leached a little higher than those of other treatments. It may be due to poor growth of rice following to reduce the nutrient uptake by rice and to increase relatively the nutrient leaching to the ground water. The proper application level of anaerobic digestion waste water as a liquid manure could be suggested to apply LM 70%+CF 30%. All treatments were the same amount of nitrogen content for the standard application amount on rice.

• Korean Journal of Soil Science and Fertilizer
• /
• v.34 no.3
• /
• pp.213-236
• /
• 2001

The ionic composition of soil solution is related to a nutrient uptake by plant. Many models for estimating ionic composition of solution have been developed, and most of them have been used for calculating a content of mineral and ionic species in a geochemical point of view. An approximation model considering both cation and anion in soil solution was developed. Variables such as pH, Eh, EC, cations(K, Ca, Mg. Na, Fe, Mn, Al, $NH_4{^+}$), anions(Si, S, P, CY, $NO_3{^-}$, $HCO_3{^-}$ and chemical equilibria of ionic species in soil solution were input into Excel sheet. The activities of soluble ion, ionpairs and complexes of input element were estimated by Newton-Raphson method using conditional equilibrium constant calculated by Davies equation and special models. Equilibrium contents of insoluble minerals and complexes were also calculated.

• Korean Journal of Soil Science and Fertilizer
• /
• v.19 no.4
• /
• pp.291-296
• /
• 1986

A pot experiment was conducted to find out the effects of water management and application of slaked lime and wollastonite on Pb uptake of rice in a Pb added soil. The soil was adjusted to 0, 150, 300 and 600 ppm of Pb concentration. The slake lime was applied at the equivalent amount of lime requirement with 150kg/10a adding and the wollastonite, 200kg/10a, respectively. The results obtained were as follows. 1. The lead contents in leaf stem and brown rice increased with increasing the soil Pb content and the ratio of Pb/(Ca+Mg) equivalent in soil but they showed no influence on yields. 2. The application of lime and wollastonite reduced Pb content in plant. 3. The lead content in plant was higher in intermittently irrigated treatment than in submersed irrigation. 4. The soil pH was increased in the order of lime, wollastonite and control. 5. $1N-NH_4$ OAC soluble Pb content in soil was higher in the submersed irrigation than in the intermittently irrigated and was higher in wollastonite application treatment than the slaked lime after harvesting.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.15 no.3
• /
• pp.198-207
• /
• 2012

In this study, we investigated the effect of ocean fertilization by deep sea water, using an ecosystem model which contains not only phytoplankton but also zooplankton. The model is based on NEMURO which consists of eleven compartments - two species of phytoplankton, three species of zooplankton, $NO_3$, $NH_4$, $Si(OH)_4$, particulate organic nitrogen, dissolved organic nitrogen and particulate silicon. We introduced nitrogen cell quota in the both species of phytoplankton, and silicon cell quota in the large phytoplankton in addition to the eleven compartments of NEMURO. We made the experiment at Izu Oshima Island in order to investigate the effect of ocean fertilization. In this experiment, we could not find clear differences between the cases with and without deep sea water. We investigated the causes of the experiment results by the model simulations. One of the causes was high concentrations of nutrients in surface seawater used in the experiment. Another was that the increase of total concentration of inorganic nitrogen does not necessarily accelerate the photosynthetic rate because inorganic nitrogen uptake rate is related to the ratio of $NO_3$ to $NH_4$. Because the model can represent the results of the experiment, we investigated the effect of ocean fertilization by deep sea water using this model. We found that the effect of ocean fertilization hardly appeared when the interval of the addition of deep sea water was too short, or the amount of deep sea water was too much. It is supposed that if the addition of deep sea water is too frequent or too much, the dilution of plankton's concentrations will exceed the effect of promoting phytoplankton's photosynthesis.

• Korean Journal of Weed Science
• /
• v.1 no.1
• /
• pp.57-68
• /
• 1981

To clarify the mode of uptake of butachlor (2-chloro-2', 6'-diethyl-N-(butoxymethyl) acetanilide) by rice seedlings, its phytotoxic action to growth and physiological activities, studies were conducted with rice seedlings, at the 6th or 7th leaf-stage, which were treated with nutrient solution containing butachlor 0, 1.8, 3.6, 7.2, 10.8 or 14.4 ppm for 1, 2 or 4 days, in other case, the solutions were thereafter renewed with the untreated nutrient solution for further growth. Uptake of butachlor by rice seedlings increased linearly with increase of its concentration and duration of uptake. Butachlor inhibited root growth more than shoot growth, furthermore, the inhibitory effect on the shoot growth was greater in height than in weight or leafing rate. After 4 day-treatment, the rates of shoot growth in weight were delayed for 4 days. Butachlor inhibited water uptake rapidly and linearly with increase of its external concentration. The reduced uptake of water was followed by slow increase in the stomatal resistance of leaves. Upon completion of butachlor treatment, rate of water uptake was recovered rapidly, but the stomatal resistance with lag in time. Butachlor did not affect the uptake of cation such as ammonium, potassium and calcium, but inhibited substantially uptake of nitrate in proportion to its concentration. Especially, butachlor did not affect synthesis and degradation of nitrate reductase. In addition, butachlor has shown much greater binding to the lipidic substances from rice roots than the proteinous material. The primary mechanism of phytotoxic action of butachlor does not seem to be its effect on the protein synthesis, but great affinity to membranes. The inhibition of water uptake, and its subsequent closure of stomates is thought very important for reduced growth under mild phytotoxicity.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.8
• /
• pp.649-654
• /
• 2009

Respirometric analysis of domestic sewage by measuring oxygen uptake rate(OUR) was carried out for the experimental assessment of the organic and biomass fractions. The data of the organic and biomass fractions in sewage is essential for the activated sludge model to optimize the biological treatment plant. As a result of this study, the fractions of readily biodegradable substrate($S_S$), slowly biodegradable substrate($X_S$), inert soluble substrate($S_I$), inert particular substrate($X_I$) and heterotrophic biomass($X_{HAB}$) were about 26.6%, 41.5%, 8.5%, 14.7% and 8.7% on the basis of chemical oxygen demand($COD_{Cr}$), respectively. And the fractions of nitrogen were also studied. The fractions of soluble nitrate nitrogen($S_{NO}$), soluble ammonia nitrogen($S_{NH}$), soluble nonbiodegradable organic nitrogen($S_{NI}$), soluble biodegradable organic nitrogen($S_{ND}$) and slowly biodegradable organic nitrogen($X_{ND}$) were about 3.7%, 64.9%, 4.7%, 9.4% and 17.4%, respectively.

• Korean Journal of Environmental Agriculture
• /
• v.29 no.4
• /
• pp.336-342
• /
• 2010

In a pot experiment, we studied the effect of nitrification inhibition on Fe reduction and P release in paddy soil and growth and nutrient uptake of rice plant. Recommended level of fertilizers, 6 kg N, 5 kg $P_2O_5$ and 4 kg $K_2O$ per 10a, were applied, and for N fertilizer urea, urea+N-serve, and $KNO_3$ were included. Four 30-day-old seedlings were transplanted in a waterlogged 9 L pot filled with Yuga series soil, and 3 pots were prepared in each N fertilizer treatment. Changes of soil redox potential and concentration of ${NH_4}^-$, ${NO_3}^-$, $Fe^{2+}$ and ${PO_4}^{3-}$ in soil solution at 10 cm depth were monitored, and also the growth and nutrient uptake of rice plants were measured. Concentration of ${NH_4}^+$ in soil solution was highest in urea+N-serve treatment, and followed by urea and $KNO_3$ treatments. Addition of N-serve could effectively inhibit nitrification in the soil. In the treatment of $KNO_3$, relatively higher ${NO_3}^-$ concentration was found at 10 cm depth soil. In urea+N-serve treatment redox potential was lower than -100 mV during the experiment, but in the treatment of $KNO_3$ the potential was maintained above 0 mV until ${NO_3}^-$ remaining in soil solution. Reduction of Fe(III) and solubilization of P were highly correlated with redox potential changes in the three N fertilizer treatments. Concentrations of Fe(II) and ${PO_4}^{3-}$ in soil solution at 10 cm depth were much higher in the urea+N-serve treatment. The most vigorous rice seedling growth was found in the urea treatment. Although the availability of N and P in soil was enhanced in the urea+N-serve treatment through the suppression of nitrification, excessive solubilization of Fe could limit the growth of rice plants.

• Journal of Bio-Environment Control
• /
• v.18 no.4
• /
• pp.354-362
• /
• 2009

This study was performed to develop a suitable nutrient solution for standard rose substrate culture in a closed hydroponic system. 1/4, 1/2, 2/3 and 1 strength of the nutrient solution made by Japan National Institute of Vegetable and Tea Science (JNIVT) were supplied. The photosynthesis rate, quality and growth of cut flower were higher in the 1/2 and 2/3 strength of nutrient solution during high and low temperature period. Based on the above results, optimum nutrient solutions (UOS) were composed by nutrientwater (n/w) absorption ratio with 1/2S ($NO_{3^-}N$ 6.8, $NH_{4^-}N$ 0.7, $PO_{4^-}P$ 2.0, K 3.8, Ca 3.0, Mg 1.2, $SO_{4^-}S$ $1.2me{\cdot}L^{-1}$) at high temperature season and 2/3($NO_{3^-}N$ 9.7, $NH_{4^-}N$ 0.8, $PO_{4^-}P$ 2.2, K 5.0, Ca 3.9, Mg 1.5, $SO_{4^-}S$ $1.5me{\cdot}L^{-1}$) at low temperature season. The results of suitability examination showed that the EC level in newly composed nutrient solution (UOS) was more stable than other nutrient solutions due to its large amount of calcium and potassium. The growth of cut flower cultivated with UOS was higher than those of other nutrient solutions. Especially, the yield of cut flowers in UOS nutrient solution increased 1.4 times than that of other nutrient solution treatments. Consequently, the new nutrient solution investigated in this experiment was suitable for rose cultivation in a closed hydroponic system.

• Korean Journal of Soil Science and Fertilizer
• /
• v.35 no.5
• /
• pp.253-263
• /
• 2002

To test for the effect of applied fertilizer and nutrients on uptake and transport for paddy rice, two paddy field trials were conducted with Dongjinbyeo in degenerated salt paddy field of Jeonbuk series from 1999 to 2000. After experiment, soil acidity, content of organic matter phosphate, silicate, potassium, calcium, and total nitrogen was increased by application of fresh cattle manure(FCM). Content of Nitrogen in soil layer leached inorganic nitrogen $NO_3$ was higher that that of $NH_4$ and was high in treatment of FCM. Content of $PO_4$ was higher in FCM than other treatments. But content of potassium was in high control. During the growth of rice plant, the amount of water consumption was 477mm. The amount of supplied nitrogen was high in treatment of no nitrogen(NN), 20% reduced application of LCU(LCU-20%), and no fertilizer. In case of phosphate, the supplied amount was more than the consumed amount with the exception of treatment "no phosphate(NP) and no fertilizer(NF)". In case of potassium, the consumed amount was more than the supplied amount in all treatments. The amount of applied nitrogen in the nutrient infiltrated water was high in treatment soil test(ST), C+FCM+Si(Silicate) and the ratio of recovered nitrogen was high in 20% reduced application of LCU. The amount of applied phosphate in the nutrient infiltrated water was high in FCM and that of applied potassium was high in 20% reduced application of LCU. Nitrogen use efficiency of paddy rice was high in 20% reduced application of LCU and use efficiency of phosphate and potassium was high in C+Si(Silicate). Grain yield of rice was high in order of 20% reduced application of LCU>C+Si=C+FCM+Si>C+FCM.