• Title/Summary/Keyword: soil salt concentration

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Optimal Storage Conditions of the Entomopathogenic Nematode, Steinernema Carpocapsae (곤충병원선충(Steinernema carpocapsae)의 최적보관을 위한 환경요인)

  • 박영진;김용균;이영근;한상천
    • The Korean Journal of Soil Zoology
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    • v.3 no.1
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    • pp.9-16
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    • 1998
  • Effects of temperature, pH, and salt concentration on the preservation of the infective juvenile entolopathogenic nematodes, Steinernema carpocapsae, were analyzed. The effects of acclimation to sublethal low temperature and glycerol concentrations on rapid cold hardening of the nematodes were also evaluated to set up the conditions for their cryopreservation. All tested environmental factors could change the storage effectiveness of the nematodes. These analyses indicated that the optinal storage condition for the nematodes consisted of $15^{\circ}C$, pH 8.5, and 0.5-1.0% salt concentration. The nematodes showed a rapid could hardening in response to $5^{\circ}C$ for 2h. Glycerol induced the nematodes to increase the cold hardiness. Its high concentration over 10%, however, gave a harmful effect on the nematode survival.

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Relationship Between Electrical Conductivity, Exchangeable Sodium Percentage and pH During Desalinization of Reclaimed Tidelands (간척지토양의 제염과정중 전기전도도와 치환성 나트륨 백분율 및 pH 사이의 관계)

  • 구자웅;은종호
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.30 no.4
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    • pp.127-133
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    • 1988
  • This study was performed to obtain the basic data analyzing salt movement and desalinization effects, and two different desalinization experiments through leaching and rinsing were carried out, using samples of silt loam soil and silty clay loam soil collected in reclaimed tidelands. The relationships between the electrical conductivity of saturation extract and the electrical conductivity at various dilutions, and the correlations between electrical conductivity, total salt concentration, exchangeable sodium percentage and pH during the desalinization of reclaimed tidelands, were analyzed by the statistical method. The results obtained from this study were summarized as follows: 1.The sample soils used in this study were saline-sodic soils in accordance with the USDA classi- fication system of salt affected soils. 2.The electrical conductivity of saturation extract could be estimated conveniently, using the electrical conductivity of extract from various different soil-water suspensions. 3.The total salt concentration could be expressed in the electrical conductivity, but there was a little difference by soil textures. 4.The regression analysis showed that the relationship between the electrical conductivity of saturation extract and the exchangeable sodium percentage during the desalinization of reclaimed lands could be described by a linear regression equation. 5.The value of pH showed a tendency to increase according as the exchangeable sodium percentage decreased during the desalinization of reclaimed tidelands.

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Salt Removal in a Reclaimed Tidal Land Soil with Gypsum, Compost, and Phosphate Amendment

  • Lee, Jeong-Eun;Seo, Dong-Hyuk;Yun, Seok-In
    • Korean Journal of Soil Science and Fertilizer
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    • v.48 no.5
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    • pp.326-331
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    • 2015
  • High salinity and sodicity of soils play a negative role in producing crops in reclaimed tidal lands. To evaluate the effects of soil ameliorants on salt removal in a highly saline and sodic soil of reclaimed tidal land, we conducted a column experiment with treating gypsum, compost, and phosphate at 0-2 cm depth and measured the salt concentration of leachate and soil. Electrical conductivity of leachate was $45-48dSm^{-1}$ at 1 pore volume (PV) of water and decreased to less than $3dSm^{-1}$ at 3 PV of water. Gypsum significantly decreased SAR (sodium adsorption ratio) of leachate below 3 at 3 PV of water and soil ESP (exchangeable sodium percentage) below 3% for the whole profile of soil column. Compost significantly decreased ESP of soil at 0-5 cm depth to 5% compared with the control (20%). However, compost affected little the composition of cations below a depth of 5 cm and in leachate compared with control treatment. It was concluded that gypsum was effective in ameliorating reclaimed tidal lands at and below a soil layer receiving gypsum while compost worked only at a soil layer where compost was treated.

Effects of Soil Amendments and Planting Miscanthus sinensis on Salt Reduction and Growth Improvement in Substrate irrigated with High Concentration of Calcium Chloride Deicing Salts (염화칼슘 제설제 고농도 처리에 따른 토양개량제와 참억새 식재 처리가 염류저감 및 생육개선에 미치는 영향)

  • Ju, Jin-Hee;Yang, Ji;Park, Sun-Young;Yoon, Young-Han
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.6
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    • pp.15-25
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    • 2019
  • Contamination of soil by deicing salt is among the important environment problems due to their toxicity and negative impact to human health and the environment. One of the effective methods for cleaning the soil from deicing salts is desalination using soil amendment-phytoremediation continuum treatment. The purpose of this study was to determine how much of the pH, EC control and Ca2+, Na+, Mg2+, and K+ taken up soil amendments and Miscanthus sinensis, and to evaluate the effect of salt reduction and growth improvement as affected by soil amendment in high concentration of calcium chloride (CaCl2) deicing salts. Results indicated that the addition of soil amendments was decrease the EC and pH, also significantly reduce the leaching of Ca2+, Na+, Mg2+, K+, a chloride ions related deicing salts, compared to the control for CaCl2 10 g/L treatment. It also resulted in an enhanced plant growth and higher plant height, leaf length, leaf width, number of leaves, fresh weight and dry weight in Hydroball treatment + Miscanthus sinensis planting continuum treatment compared to the treatment that planted Miscanthus sinensis only. Therefore, we concluded that soil amendments might be attributed to an accumulation of deicing slats in the roadside soil, resulting in the improvement of Miscanthus sinensis growth.

Soil Salt Prediction Modeling for the Estimation of Irrigation Water Requirements for Dry Field Crops in Reclaimed Tidelands (간척지 밭작물의 관개용수량 추정을 위한 토양염분예측모형 개발)

  • 손재권;구자웅;최진규
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.36 no.2
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    • pp.96-110
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    • 1994
  • The purpose of this study is to develop soil salt prediction model for the estimation of irrigation water requirements for dry field crops in reclaimed tidelands. The simulation model based on water balance equation, salt balance equation, and salt storage equation was developed for daily prediction of sa]t concentration in root zone. The data obtained from field measurement during the growing period of tomato were used to evaluate the applicability of this model. The results of this study are summarized as follows: 1.The optimum irrigation point which maximizes the crop yield in reclaimed tidelands of silt loam soil while maintaining the salt concentration within the tolerance level, ws found to be pF 1.6, and total irrigation requirement after transplanting was 602mm(6.7 mm/day)for tomato. 2.When the irrigation point was pF 1.6, the deviation between predicted and measured salt concentration was less than 4 % at the significance level of 1 7% 3.Since the deviations between predicted and measured values data decrease as the amount of irrigation water increases, the proposed model appear to be more suitable for use in reclaimed tidelands. 4.The amount of irrigation water estimated by the simulation model was 7.2mm/day in the average for cultivating tomato at the optimum irrigation point of pF 1.6.The simulation model proposed in this study can be generalized by applying it to other crops. This, model, also, could be further improved and extended to estimate desalinization effects in reclaimed tidelands by including meteorological effect, capillary phenomenon, and infiltration.

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The Solution of Upward Salt Diffusion in Floodeol Soil using Laplace Transformation (침수상태(湛水狀態)에서 토양(土壤) 염분(鹽分) 확산(擴散) 상승(上昇) 해석(解析)에 Laplace변환 이용)

  • Oh, Yong-Taeg;van der Molen, W.H.
    • Korean Journal of Soil Science and Fertilizer
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    • v.28 no.3
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    • pp.233-240
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    • 1995
  • Fick's diffusion equation was transformed into algebraic subsidiary equation with its initial and boundary conditions through Laplace transformation, and the subsidiary equation was transformed back on the basis of Burington's table of inverse transformations so that it became the solution of Fick's equation. The initial and boundary condition was for upward diffusion of salts into flooding water of constant depth from uniform polder soil of infinite depth containing constant concentration of salt. The derived solution was tested through comparison for its conformability with other solutions of simpler initial and boundary conditions. The importance of shallow transplanting of rice seedlings and salt removing by growing rice was mentioned on the basis of very slow desalting rate by diffusion calculated from the derived solutions.

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Study on the Salt Tolerance of Rice and Other Crops in Reclaimed Soil Areas 12. On the Salt Tolerance of the Rice Seeldings Grown under the Land and Water Conditions in the Reclaimed Salty Areas (간척지에서 수도 및 기타작물의 내염성에 관한 연구 12. 육묘와 수묘의 염분간척지에서의 내염성에 관하여)

  • 임형빈
    • Journal of Plant Biology
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    • v.13 no.4
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    • pp.23-31
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    • 1970
  • The rice variety, Kwanok, was reared in the water and land beds and transplanted to the reclaimed soil area, having an average salt concentration of 0.39%. Two levels of the moderate and late season cultures with 4 treatments were used. The K and Si contents of the stem part of land bed seedlings were somewhat smaller, but total carbohydrate remarkably larger, the C/N ratio was accordingly greater than water bed seedlings. The rooting ability of land bed seedlings was vigorous markedly in culture solutions, to which added various concentrations of NaCl, The rooting ability of each seedling water not much declined in theculturing solution of up to 9.4mmhos/cm, (0.6%) of salt concentration, but it was drastically declined in the salt concentration over that. It seemed that the critical salt concentration for the rooting rice plant. The land bed seedlings in each salty condition markedly decreased compared with the water bed seeldings in transpiration rate and it showed a stronger drought resistance and contained a large amount of chlorophyll at transplanting stage, and also showed higher stability of chlorophyll at rooting stage in the salt treatment. The number of panicles, panicle weight, number of grains per panicle and ratio of matured grains of the rice plant grown by the land bed seedlings were much greater and 1,000 grain weight was less than from water bed seedlings. The cultural practices with the land bed seedlings increased the rough rice yields by 15% and 11%, respectively, compared with the yields of the moderate and late season cultures by water bed seedlings.

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A Basic Study on Sugar Beet Culture in Reclaimed Salty Area 1. On the Sugar Accumulation of Sugar Beet in Reclaimed Salty Area (간척지에 있어서의 사탕무우 재배에 관한 기초적 연구 1. 간척지에서 사탕무우의 당축적에 관하여)

  • 임형빈
    • Journal of Plant Biology
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    • v.20 no.1
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    • pp.23-27
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    • 1977
  • In order to investigate the possibility of sugar beet culture in reclaimed area of our country and the salt tolerance of sugar beet, a variety Kawemegapoly was used for experimentation in plots of various salt concentration arranged in Kimpo reclaimed area located at Kyongkido Province. The salt concentration of cultivating layer of the field in the west coast of Korea began to decline from the middle of June and rises again in the middle of October growing season of sugar beet as generally seen in relaimed paddy fields of Korea. The soil of less than 0.5% salt concentration is most suitable for the culture of sugar beet has bery strong salt tolerance. The sugar accumulation of sugar beet in each plot declined once in the middle part or in latter September and began to proceed again from the early of October. Such temporary retrocession of sugar accumulation was observed.

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Effect of Salt Concentration on Methane Emission in a Coastal Reclaimed Paddy Soil Condition: Pot Test (간척지 논 토양의 염 농도가 메탄 배출에 미치는 영향)

  • Lim, Chang-Hyun;Kim, Sang-Yoon;Jeong, Seung-Tak;Kim, Gun-Yeob;Kim, Pil-Joo
    • Korean Journal of Environmental Agriculture
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    • v.32 no.4
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    • pp.252-259
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    • 2013
  • BACKGROUND: Salt accumulation in coastal reclaimed soil can decrease plant growth and productivity, which could lead to considerable variation of methane($CH_4$) emission in a rice paddy. The objective of this study was to evaluate the effect of salt concentration on $CH_4$ emission in a coastal reclaimed soil. METHODS AND RESULTS: The effect of salt concentration on $CH_4$ emission and rice growth characteristics was studied by pot test, which packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Electrical conductivity(EC) of each treatment was controlled by 0.98, 2.25, 5.05 and 9.48 dS/m and $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. The $CH_4$ emission rate was significantly decreased with increase of salt accumulation, but total $CH_4$ flux in EC 5.50 dS/m treatment was lower than those of EC 9.48 dS/m treatment. It seems because of higher content of water soluble $SO{_4}^{2-}$ in EC 5.50 dS/m treatment than those of EC 9.48 dS/m treatment. Rice growth and grain yield were significantly decreased with increase of salt accumulation. Soil properties, especially EC and pH were negatively correlated with $CH_4$ flux, while rice growth characteristics like plant height and tiller number show significantly positive correlation with $CH_4$ flux. CONCLUSION(S): Conclusively, salt accumulation significantly decreased $CH_4$ flux in a rice paddy, which could be useful information for evaluating $CH_4$ flux in reclaimed area in Korea.

Evaluating germination of lettuce and soluble organic carbon leachability in upland sandy loam soil applied with rice husk and food waste biochar (왕겨 바이오차 및 음식물쓰레기 바이오차가 밭 사양토에서 상추발아 및 수용성 유기탄소 용출에 미치는 영향 평가)

  • Han, Kyung-Hwa;Zhang, Yong-Seon;Jung, Kang-Ho;Cho, Hee-Rae;Sonn, Yeon-Kyu
    • Korean Journal of Agricultural Science
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    • v.41 no.4
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    • pp.369-377
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    • 2014
  • This study was carried out to evaluate the effect of rice husk (RHB) and food waste biochar (FWB) on upland soil with sandy loam texture, in terms of physico-chemical analysis, lettuce seed germination test, and orgainc carbon leaching experiment. RHB and FWB had different physico-chemical properties each other. Carbon to nitrogen ratio (C/N ratio) of RHB was 32, showing two times higher than that of FWB. FWB had high salt and heavy metal content, compared to RHB. This is probably due to different ingredients and production processing between two biochars each other. Results of germination test with Lettuce showed lower germination rate when FWB was applied because of higher salt concentration compared to control and RHB. Organic carbon leaching test using saturated soil column (${\Phi}75{\times}h75mm$) with $10MT\;ha^{-1}$ biochar application rate, showed higher saturated hydraulic conductivity in rice husk biochar treatment column, compared to control and food waste biochar treatment. The highest total organic carbon concentration in column effluent was lower than those in both of rice husk biochar and food waste biochar, whereas the differences was negligible after 9 pore volumes of effluent. Consequently, biochars from byproducts such as rice husk and food waste in sandy loam textured upland soil could enhance a buffer function such as reduction of leaching from soil, but the harmful ingredient to crops such as high salt and heavy metals could limit the agricultural use of biochars.