• 한국토양비료학회지
• /
• 제50권1호
• /
• pp.65-70
• /
• 2017

Soil was regarded as infinite resources but recently, soil is considered as invaluable resources that we need to protect and conserve. Main objective of this research was to evaluate soil value in terms of soil carbon contents. Soil was classified into forest, paddy, upland, and grass. Carbon contents in each soil was calculated based on soil chemical properties. Calculated soil carbon contents was ranged $15.31-108.86mg\;kg^{-1}$. Based on soil carbon contents, soil value was assumed adapting economic concepts. Calculated total soil value based on soil carbon contents was about 18.46 trillion won. Among others, carbon contents in forest was the highest and value was assumed 11.95 trillion won followed by paddy field (3.7 trillion won).

• 한국환경과학회지
• /
• 제11권3호
• /
• pp.227-234
• /
• 2002

Laboratory experiments were conducted to examine the behavior of metalaxyl in environment which was used as pesticide in green soil of golf course and as functions of the characteristics of adsorption, desorption and degradation in soil texture and organic matter contents. Acid water containing metalaxyl was conducted to evaluate the effects on adsorption, desorption and degradation. The adsorption of metalaxyl played more significant role in organic contents than clay contents, and pH Increases more pH 2.5 than pH 5.6. The desorption of metalaxyl from contaminants soil decreased higher organic contents LS-soil than S-soil, but the desorption amount of metalaxyl increased more pH 5.6 than pH 2.5. The rate of degradation of metalaxyl in green soil environmental increased higher organic contents LS-soil than S-soil and decreased more pH 2.5 than pH 5.6. These results indicated that the behavior of metalaxyl of the green soil was affected the soil texture of the golf course. Increasing of organic contents, the adsorption amount of metalaxyl on soil increased. Moreover the decrease of the pH of solution increased adsorption amounts and decreased desorption amounts. As the results, the transportation of metalaxyl in soil decreased the acidic rates. The acidification of soil by the acid rain increased the adsorption amount of metalaxyl, but the degradation of metalaxyl decreased. Therefore, it is possible to sustain contamination in run-off the stream and ground water by residuals in soil.

• 한국토양비료학회지
• /
• 제45권6호
• /
• pp.920-924
• /
• 2012

This study was performed to estimate total contents of arsenic (As) by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines. The soil was collected from paddies near abandoned mines. Soil pH, electrical conductively (EC), organic mater (OM), available phosphorus ($P_2O_5$), and exchangeable cations (Ca, K, Mg, Na) were measured. Total contents of As and extractable contents of metals were analyzed by ICP-OES. From stepwise analysis, it was showed that the contents of extractable As, available phosphorus, extractable Cu, exchangeable K, exchangeable Na, and organic mater significantly influenced the total contents of As in soil (p<0.001). The multiple linear regression models have been established as Log (Total-As) = 0.741 + 0.716 Log (extractable-As) - 0.734 Log (avail-$P_2O_5$) + 0.334 Log (extractable-Cu) + 0.186 Log (exchangeable-K) - 0.593 Log (exchangeable-Na) + 0.558 Log (OM). The estimated value in total contents of As was significantly correlated with the measured value in soil ($R^2$=0.84196, p<0.0001). This predictive model for estimating total As contents in paddy soil will be properly applied to the numerous datasets which were surveyed with extractable heavy metal contents based on Soil Environmental Conservation Act before 2010.

• 한국군사과학기술학회지
• /
• 제18권2호
• /
• pp.125-130
• /
• 2015

Vehicles and UGV(Unmanned Ground Vehicle) need a variety of road informations, such as road profile, soil type and soil water contents, to run a cross country course. Especially, soil water contents are very important factor to judge the vehicle mobility, because it can change soil strength. This paper describes the real-time measuring method of soil water contents by using the soil thermal conductivity.

• Journal of Ecology and Environment
• /
• 제32권4호
• /
• pp.295-304
• /
• 2009

To understand the properties of soil in Dokdo, we collected soil samples from 12 locations on Seodo and 23 locations on Dongdo, in Dokdo of Gyeongsangbuk-do Province in 2007-2008 and analyzed the soil's physical and chemical characteristics. Sand comprises the largest component (49.37%) of Dokdo soil, followed by silt (40.70%) and clay (9.93%). The soil structure consists mostly of sand loam, followed by loam and silt loam. The pH level of soils from Dokdo varied dramatically among sampling sites and seasons, ranging from 3.36 to 8.02. The total ion content of Dokdo soil also varies greatly among survey places and periods, but in general the total ion content was high in summer when vegetation develops, and low in spring. The exchangeable cation contents of the soil showed low levels in samples where the soil pH was low, including habitats dominated by Agropyron tsukushiense var. transiens and Echinochloa crus-galli, whereas the exchangeable cation contents were high where the organic contents were high, as in habitats dominated by Liriope platyphylla and Artemisia japonica subsp. littoricola. Soil N contents varied greatly among survey sites and higher N contents were found in soil inhabited by Chenopodiaceous plants than in habitats inhabited by other plants. The substantial differences in phosphorus contents among sites were related to excrement of black-tailed gulls. To understand the basic physical and chemical features of the soil on Dokdo, it will be necessary to conduct seasonal and long-term research on soil pH, ion contents, organic contents, N and P, as well as obtaining precise data from samples collected at different depths.

• 한국자원식물학회지
• /
• 제35권6호
• /
• pp.762-769
• /
• 2022

Growth characters and ingredient contents of two-year-old bellflower (Platycodon grandiflorum) roots were investigated under both control and soil moisture treatment condition using soil moisture control system including soil sensing and automatic water supply chain in this study. Root diameter, fine root number, root length, fresh weight and dry weight of the plant were significantly influenced by the automatic water treatment, 20%, 30%, 40% and 50%, respectively. Ingredient contents of the two-year-old roots in bellflower plants were detected in the 20% and 50% of controlled soil moisture content. Contents of amino acids were decreased by the soil moisture treatment, meanwhile, contents of minerals were not showed significant decrease except for phosphorus content. Showing no difference in proline and tyrosine, fourteen of the amino acid contents were gradually decreased by the increased soil moisture contents, with significant decrease in serine, glycine, alanine, leucine, lysine and histidine at 20% treatment.

• 한국토양비료학회지
• /
• 제51권1호
• /
• pp.61-70
• /
• 2018

This study was carried out to review and compare crop cultivations upon chemical properties of paddy soil and qualitative characteristics of rice in Sejong-city from a point of view of farming extension to rice farmers and to utilize the result of the study as a basic guideline for precise agricultural practice. The pH in soils of Sejong was about 6.1-6.6 and had no difference with an average pH of paddy soils in Chung-Nam with pH 6.1. However, the average of organic matter, calcium (Ca) and available silicate in Sejong was lower than the average of them in Chung-Nam. The yields of rice were higher in 2010 than in 2011 and 2012, and the protein contents of rice were the highest in 2011 while the lowest water contents of rice in 2011. The protein contents upon regions were the highest in 2011 with 6.1%, and the amylose contents were the highest in Yeondong-myun, Jeoneu-myun, and Yeonseo-myun in 2010 while Kumnam-myun and Jeondong-myun were the highest in 2012. With the increase of precipitation, the protein content level in rice was increased while the amylose content level tended to decrease. Correlations between the chemical properties of paddy soil and the quality of rice and between level of organic matter in soil and amylose contents were negative (r = -0.507), and the correlation between the moisture contents and amylose contents (r = 0.419) and between the water contents and whiteness (r = 0.485) were positive. Because the quantity and quality of rice yield is determined by the soil characteristics, the consultation to farmers for the proactive soil analysis and for the maintenance of stable level of pH, organic matter and available silicate based on historical results of analysis is highly recommended. Also, the analysis on the effect of the weather and the soil characteristics affecting the quality and quantity of rice would be another good way.

• 한국농공학회지
• /
• 제45권6호
• /
• pp.153-161
• /
• 2003

The purpose of this paper is to investigate the soil-water characteristic curves for an unsaturated soil. To this ends, a series of suction measured test was conducted on the selected 4 kinds of soils taken from different sites of Korea, using modified pressure plate apparatus. Form the test results, the water contents, degree of saturation and volumetric water contents were analyzed with the suction. And the soil-water characteristic curves of unsaturated soil were drawn from the test results for various factors. The characteristic curves drawn with water content vs matric suction were classified certainly the difference in wet side but were not classified in dry side. The characteristic curves drawn with degree of saturation vs matric suction for unsaturated soil were shown the opposite inclination as compared with the former curve. But the characteristic curve with volumetric water content vs matric suction was described suitably not only in wet side condition but also in dry side. And it was found that the volumetric water contents of loose soil was high at the initial condition but that of dense soil was high at final condition (dry side).

• 한국토양비료학회지
• /
• 제44권6호
• /
• pp.1080-1084
• /
• 2011

Predictive model for estimating total contents of cadmium (Cd) and lead (Pb) was developed by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines in 2009 and 2010. Soil properties, e.g. pH, electrical conductivity (EC), organic matter (OM), available phosphorus ($P_2O_5$), and exchangeable cations (i.e. Ca, Na, K, Mg) were measured. Total contents of Cd and Pb as well as extractable contents of metals were analyzed by ICP-OES. Results showed that the total and extractable contents were estimated to be 3.55 and $0.27mg\;kg^{-1}$ in Cd and 83.38 and $24.32mg\;kg^{-1}$ in Pb on the average. From stepwise analysis, it was found that the contents of extractable Cd, Zn, Cu, as well as exchangeable Na were significantly influenced on estimation of the total contents of Cd in soil. Moreover, it also showed that the contents of extractable Pb, Zn, and Cu significantly affected estimation of the total contents of Pb in soil. More significant relationship between estimated and measured value in total contents of Pb was observed than those of Cd ($R^2$=0.87, p<0.0001). This demonstrates that extractable contents of metal are influenced more on estimation of total contents of Cd and Pb in soil than soil properties.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 1999년도 추계학술발표회
• /
• pp.57-60
• /
• 1999

Geochemical study was carried out to find out soil contamination at the heaped soil, moved from bottom of the storage pond in Pohang industrial complex, in Moondug, Chemical analysis showed that contents of heavy metals in the soil were higher than those of the ordinary soil. Contents of Cu and Cd in the soil exceeded Korean standard of soil contamination. Especially content of Cu exceeded Korean standard of soil contamination(50ppm) at the six points and at one point content of Cu was 113.3ppm. Contents of Be were so higher than U.S RCRA standard(0.2ppm) that they can affect soil environment. The followed research about relation between pollutant and soil and proper measures are required to prevent soil contamination from affecting environment of Moondug.