• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.87-94
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• 2005

This study was carried out to investigate the effect of soil types and soil properties on wood preservative leaching. Radiata pine (Pinus radiata Don.) sapwood stakes, which had been treated with 2.0%(w/v) CCA, were leached for 12 weeks by a common laboratory method in four different soils and for 14 days by the AWPA standard leaching method in water. The physical and chemical properties of the four soils were determined, and the percent leaching of the individual component of CCA was correlated with the various soil properties. The data show that leaching of preservative chemicals from treated wood exposed to soil is influenced by the type of soil. The preservative leaching was greater when wood was exposed to water than when the wood was in contact with water-saturated soil. The greatest chromium, copper and arsenic leaching from CCA-treated stakes were observed in the sandy loam, loam, and sand, respectively, and the least amount of leaching of CCA components occurred in the silty loam. The leaching of preservative components from treated wood is extremely complex and appears to be influenced differently by the soil properties. The extent of copper leaching from CCA treated wood appears to be related to exchangeable Mg and sum of bases. There is a reasonably good relationship between chromium leaching and exchangeable Mg, and between arsenic leaching and exchangeable K, soil Ni, Mn, Fe, Cr, or Cu content. Since this study was conducted based on laboratory leaching method using small cross-sectional dimensions; thus, data obtained from this experiment should not be used to predict leaching characteristics from commercial-size wood used in real situation. Accordingly, further studies are necessary using outdoor ground-contact leaching.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.36-41
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• 1983

These studies were carried out to investigate the effects of potassium salts on the changes of chemical properties in submerged soil. Rice plants were cultured in submerged soil using potassium salts. Obtained results were as follows. In the submerged soil cultured with rice plants the value of pH was higher in the potassium chloride plot than in the potassium sulfate plot. The leaching of cations such as calcium, magnesium, potassium and ammonium were higher in the potassium chloride plot than in the potassium sulfate plot. On the other hand, the leaching of phosphate ion was slightly higher in the potassium sulfate plot than in the potassium chloride plot. The leaching of iron was higher in the planted plot than in the non-planted plot, but that of silica was higher in the non-planted plot than in the planted plot. However, the leaching of iron and silica was not affected by potassium salts.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.168-172
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• 2002

돈분뇨를 토양에 살포시 경과일에 따른 이온들의 용탈 특성을 살펴보기 위해 질산성 질소 농도가 높고, 양돈사육두수가 많은 서ㆍ북부 지역의 토양에 돈분뇨를 살포, 비살포시 1~32일 경과 후에 일정량의 강수(100mm)시 용탈되는 각종 이온의 용탈 정도를 검토한 결과 다음과 같은 결론을 얻었다. 토양에 134kg T-N/ha로 살포시 질사성질소는 1.18mg/L.day의 질산화가 이루어졌고, 37kg $Cl^{-}$/ha로 살포한 염소이온의 용탈율은 1일에서 4일까지는 1.0mg/L.day로 증가하다가, 그 후 0.2mg/L.day로 용탈속도가 1/5로 감소하였다. 그러나 대조구는 질산성 질소, 염소이온 모두 거의 변화가 없었다.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.59-67
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• 1998

토양중 침투성 살충제 carbofuran과 제초제 petilachlor의 용탈행적을 구명하기 위하여 물리화학적 성질이 상이한 2종의 논토양으로 충전된 토양 column (내경 5cm ${\times}$ 길이 30cm)에 $^{14}C$-표지 화합물을 각각 처리한 후 벼 (Oryza sativa L.)를 생육시키면서 벼를 심지 않은 경우를 대조구로 하여 8주 동안 주당 95.2 ml씩 용탈시켰다. Carbofuran의 경우 토양 column에서 용탈된 $^{14}C$ 방사능의 양은 벼를 재배하지 않은 토양 A와 B에서 각각 총처리 방사능의 74.8와 92.3%였으며, 벼를 재배한 토양에서는 각각 45.1%와 69.7%였다. 반면에 petilachlor의 경우 벼를 재배한 토양 column에서는 각각 총처리 방사능의 2.4%와 5.0%가 용탈되었으며, 벼를 재배한 경우는 각각 3.1%와 8.2%가 용탈되었다. 토양에 처리한 [$^{14}C$]화합물 모두 벼의 생육유무에 관계없이 양이온치환용량, 유기물 및 점토의 함량이 적은 토양 B에서 $^{14}C$ 방사능의 용탈이 증가되었다. 토양 column중 carbofuran의 이동성은 매우 높은 반면에 petilachlor는 매우 낮았으며, 이는 그들의 토양흡착과 수용성에 기인된 것으로 판단된다.

• The Korean Journal of Pesticide Science
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• v.17 no.3
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• pp.168-177
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• 2013

This experiment was carried out to estimate leaching potential of thirteen endocrine disruptor-suspected pesticides in upland soils using soil columns (5 cm I.D. ${\times}$ 35 cm H.) packed with soil A (sandy loam) and soil B (loam). When 12.6 mL of water, average precipitation in Cheongju area during the period from June to August, 2001-2010, was percolated through soil column packed with soil A every day for 21 days, no pesticides were detected from leachate, with the exception of metribuzin which was detected with negligible. Also, when 2 L of water was percolated consecutively five times through soil columns packed with soil A and B, irrespective of soil types, cypermethrin, endosulfan, fenvalerate, parathion and trifluralin, which were very low water solubilities and high soil $K_{oc}s$, were not detected from leachate and were distributed mostly in the depth of 0-5 cm, representing that water solubility and soil $K_{oc}$ are major contributing factors to their leaching behavior. Despite high average leaching rates in carbaryl and methomyl, actual possibilities of ground water contamination in the agricultural environment by them would be very low, considering that the negligible amount of pesticide was percolated through a lysimeter with an undisturbed soil core simulating the field conditions, while most of pesticide was percolated through a soil column with the disturbed soil profile.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.311-317
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• 1983

These studies were carried out to investigate the effects of rice straw on the leaching of chemical constituents in paddy soil. Rice plants were cultured in paddy soil to which rice straw was applied and then chemical properties of percolated water were analysed. The results were as follows. The leaching of calcium and magnesium was affected by rice straw application in the early stages of plant growth and by rice root activity in the late stages. The application of the straw promoted the reduction of the soil followed by increasing the leaching of iron and manganese. The leaching of potassium, ammonium-nitrogen and chloride was not due to the application of rice straw and the leaching of carbon dioxide increased with the application of rice straw, at the same time chemical properties seemed to be affected by rice root activity. Generally, cation and anion leached in the percolated water were equivalent. Calcium, magnesium, Fe as cation and $HCO_3$, $SO_4{^{-2}}$ as anion were important constituents in the percolated water from paddy soil.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.162-167
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• 1983

These studies were carried out to investigate the effects of organic matter on the leaching of chemical constituents in paddy soil. Rice plants were cultured in paddy soil to which rice straw and compost were applied and then chemical properties of percolated water were analysed. The results were as follows: In the paddy soil cultured with rice plants, the pH value of soil was higher in the compost plot than in the rice straw plot. The leaching of iron, managanese, calcium, magnesium and phosphate was increased by cultivation of rice plant, but that of potassium, ammonium, and silica was decreased. When rice straw was applied in the paddy soil, the leaching of iron, managanese, phosphate and silica was increased during the growing periods, while that of calcium, magnesium, potassium and ammonium was increased by application of compost.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.97-102
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• 2001

Cheju island depends on a hydrogeologically vulnerable aquifer system as its principle source of drinking water. Most of golf courses are located in the area which is important for the ground water recharge, and pesticides are applied to golf courses often at relatively high rates. Therefore, turf pesticides in golf course should be applied without adversely impacting ground water. In this experiment, downward movement of pesticides was monitored in model greens of golf course, where different adsorbents were layered in 3-cm thickness at 35-cm depth, and effect of the adsorption layer on the leaching loss of pesticides was investigated. Major leachings were observed in the periods of heavy rain and very limited leaching was observed under artificial irrigation. Fenitrothion and triadimefon, which have relatively short persistence and high adsorption coefficient, were found in the leachate in low concentrations only at the first rainfall event, around 20 days after the pesticide application. However, diniconazole, which has a relatively long half-life (97 days), was detected in the leachate during the whole period of experiment and concentration was much higher than those of the other pesticides. Maximum leachate concentrations were 1.9, 10.3, and 84.5 ${\mu}l^{-1}$ for fenitrothion, triadimefon, and diniconazole, respectively. Therefore, in golf course green which allows rapid water percolation and has extremely low adsorption capacity, persistence in soil could be more important factor in determination of leaching potential of pesticides. Total quantity of pesticides leached from the model green was <0.2% for fenitrothion and triadimefon and 1.8% for diniconazole. Adsorption layers significantly reduced pesticide leaching, and active carbon and Orpar were more effective than zeolite. In the model green having adsorption layer of active carbon or Orpar, leaching loss of pesticides was reduced below 0.01% of the initial application.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.7-16
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• 2002

Contamination of groundwater by agrochemicals used in the regional-scale Is now a major environmental problem, and this is especially true for Cheju island where virtually all potable water is from groundwater. The objective of this study was to assess leaching potential of eight pesticides in soils of citrus orchards using groundwater ubiquity score (GUS), retardation factor (RF) and attenuation factor (AF). Considering GUS estimated in 30 citrus orchard soils, metribuzin and metolachlor were classified as leacher, alachlor in volcanic ash soils and linuron in non-volcanic soils were classified as leacher, but chlorothalonil and chlorpyrifos were classified as non-leacher. For RF values, metribuzin was classified to be mobile in soils of low organic carbon, metolachlor and alachlor were classified to be moderately immobile in most soils, but linuron, diuron, diniconazole, chlorothalonil and chlorpyrifos were all classified to be very immobile. For AF values, diniconazole, chlorothalonil, and chlorpyrifos were classified to be very unlikely leachable in all of the soils, metribuzin was classified to be likely leachable, and metolahclor, alachlor, linuron and diuron were classified to be leachable only in non-volcanic soils. Although there were some variations in the relative potential of teachability of pesticides estimated with the three different indices, the ranking was essentially determined on the base of the intrinsic properties of the chemicals and environmental properties. Among the eight pesticides, metribuzin, metolachlor, and alachlor, which have high water solubility and low $K_{oc}$ values, have a significant leaching potential especially in non-volcanic ash soils of low organic carbon. But diniconazole, chlorothalonil, and chlorpyrifos, which have low water solubility and high $K_{oc}$ values, were classified to be very immobile in all of the soils. Therefore, to lower the possibility of pesticide contamination of the groundwater in Cheju island, those pesticides which have high water solubility and low $K_{oc}$ values should be used with care in soils of low organic carbon including non-volcanic ash soils.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.53-63
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• 2005

This study attempted to obtain the basic data of utilizable possibility of preservative treated wood as a material used in a marine ranch. To evaluate the leaching stability of CCA-, CCFZ-, and ACQ-treated woods in seawater, the specimens treated with 2% and 3% (w/v) of CCA, CCFZ, and ACQ were exposed to deionized water, synthetic seawater and natural seawater for 41 days and then each component released was periodically determined. There was little amount of copper and chromium released from CCA-treated wood exposed in both deionized and seawater. Although relatively large amount of arsenic was released from CCA-treated wood, the release rate in seawater was lower than that in deionized water. The release rate of chromium and zinc from CCFZ-treated wood were somewhat greater in deionized water, but lower in seawater than in deionized water. Retention level and salinity of synthetic seawater had little effect on the release rate of components. The ACQ-treated wood had greater copper release than CCA- and CCFZ-treated wood, and the amount of copper released did not affected by leaching media used.