• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.2
• /
• pp.297-302
• /
• 2011

Acid drainage generated by pyrite oxidation has caused the acidification of soil and surface water, the heavy metal contamination and the corrosion of structures in abandoned mine and construction sites. The applicability of Na-acetate (Na-OAc) buffer and/or Na-silicate solution was tested for suppressing pyrite oxidation by reacting pyrite containing rock and treating solution and by analyzing solution chemistry after the reaction. A finely ground Mesozoic andesite containing 10.99% of pyrite and four types of reacting solutions were used in the applicability test: 1) $H_2O_2$, 2) $H_2O_2$ and Na-silicate, 3) $H_2O_2$ and 0.01M Na-OAc buffer at pH 6.0, and 4) $H_2O_2$, Na-silicate and 0.01M Na-OAc buffer at pH 6.0. The pH in the solution after the reaction with the andesite sample and the solutions was decreased with increasing the initial $H_2O_2$ concentration but the concentrations of Fe and $SO_4^{2-}$ were increased 10 - 20 times. However, the pH of the solution after the reaction increased and the concentrations of Fe and $SO_4^{2-}$ decreased in the presence of Na-acetate buffer and with increasing Na-silicate concentration at the same $H_2O_2$ concentration. The solution chemistry indicates that Na-OAc buffer and Na-silicate suppress the oxidation of pyrite due to the formation of Fe-hydroxide and Fe-silicate complex and their coating on the pyrite surface. The effect of Na-OAc buffer and Na-silicate on reduction of pyrite oxidation was also confirmed with the surface examination of pyrite using scanning electron microscopy (SEM). The result of this study implies that the treatment of pyrite containing material with the Na-OAc buffer and Na-silicate solution reduces the generation of acid drainage.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.5
• /
• pp.817-821
• /
• 2012

Soil samples collected from abounded mines of Boryeong area in South Korea were used in isolating bacterial strains and their capacity to solubilize inorganic phosphates and heavy metal tolerance were assessed in vitro. Three different inorganic phosphate sources (Ca phosphate, Fe phosphate, and Al phosphate) and four different heavy metals (Co, Cd, Pb and Zn) each with three concentrations ($100{\mu}g\;mL^{-1}$, $200{\mu}g\;mL^{-1}$, and $400{\mu}g\;mL^{-1}$) were used. The bacterial isolates PSB-1, PSB-2, PSB-3, and PSB-4 solubilized significantly higher amount of Ca phosphate during the first five days of incubation though subsequent drop in soluble phosphorus level in the medium was observed at the later stage (after 5 days) of the incubation. Solubilization of Ca phosphate and Fe phosphate was concomitant with the acidification of the culture medium compared to the control where it remained constant. Isolated strains could solubilize Fe phosphate to certain extent ($25-45{\mu}g\;mL^{-1}$) though solubilization of Al phosphate was found negligible. All the isolates were tolerant to heavy metals (Cd, Pb, and Zn) up to the concentration of $400{\mu}g\;mL^{-1}$ except PSB-1 and PSB-8, which were shown to be vulnerable to Co even at $100{\mu}g\;mL^{-1}$. Heavy metal tolerant strains should be further evaluated for plant growth promoting activities also under field conditions in order to assess their agricultural and environmental significance.

• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.5
• /
• pp.311-317
• /
• 2000

Acid sulfate soil and potential acid sulfate soil material are worldwide in distribution and are problematic in agriculture and environment due to their present and potential acidity developed by the oxidation of sulfides. Most of them are sedimentary origin and a few cases are reported as volcanic or metamorphic origin. We report a potential acid sulfate soil material originated from volcanic activity during Mesozoic. A profile of Bongsan series-weathered nonpyritic andesite-hydrothermally altered pyrite rich andesite was studied with field examination, chemistry, and mineralogy. Once, the pyrite rich andesite was exposed to atmosphere by excavation and leveling works for a residential area and the lay out site had subsequent acidification problem of soil and surface water. The parent material and soil profile of Bongsan series had no signs of presence of pyrite and acid sulfate weathering such as yellow mottles. However, the hydrothermally altered andesite substrata contained significant amount of pyrite showing characteristics of hydrothermal origin such as cubic and pyritohedron morphology and occurrence along cracks.

• Journal of Korean Society of Forest Science
• /
• v.78 no.1
• /
• pp.11-25
• /
• 1989

Four regions have been selected and surveyed to investigate the effects of air pollution and acid deposition on forest ecosystem. They were Seoul as urban region, Yeochon and Ulsan as industrialized region, and Kangwondo as uncontaminated region. Soil pH and the distribution of elements were analyzed in process of time for three years as well as by distance from pollution sources. In general, forest soils acidified in process of time from pollution sources to suburban areas. Hydrogen ion concentration in forest soils increased in 1988 as much as 60% of that in previous year. Average soil pH values in coniferous forest were 4.45 in Seoul, 4.54 in Yeochon, 4.81 in Ulsan, and 6.03 in Kangwondo. Forest soil pH increased with the distance from pollution sources to suburban areas at constant rate within short ranges (up to 30 km) and at decreasing rate within long ranges (up to 200 km). On the contrary, sulfur content in soils decreased every year except in Yeochon region. Base saturation of forest soils in polluted regions were all below 20% level compared with 70% in Kangwondo region. Active aluminum content in soils increased with the soil acidification at the highest rate in Yeochon, and the next in Ulsan and Seoul. Heavy metal content such as copper and zinc in tree tissues were the lowest in Kangwondo region, and the next in Yeochon, Seoul and Ulsan.

• Korean Journal of Environment and Ecology
• /
• v.24 no.5
• /
• pp.566-574
• /
• 2010

This study was carried out for the purpose of understanding the situation of the urban forest and presenting basic data bases for a proper management plan through the analysis of forest vegetation and soil characteristics. In three representative urban forests of Deajeon, we analyzed the differences of vegetation and soil properties in each geological location. The indices of ecological health such as Species Diversity and Maximum Species Diversity are increasing in the order of Namseon Park, Wolpyung Park and Mt. Bomun; the first is in the center of the city, the second is well-conserved inner-city park and the third is in the border of the city. In the soil analysis of Namseon Park where human disturbance is strong, the surface fuel bed was very thin just 0.5cm and the soil was harder than the other two urban forests, the soil hardness was $0.5{\sim}3.7kg/cm^2$. All three urban forests showed low $pH_{1:5}$ under 5.0 except Robinia pseudo-acasia association of Wolpyung and low exchangeable cation level. These results say that the urban forests of Deajeon have been being acidified severely and the eluviation of exchangeable cation is proceeding. The organic matter and the available phosphate level was lower than the average level of Korean forest. It means that nutrition supply is not sufficient. In Daejeon urban forests, the management plan of urban forest is necessary according to the analysis result of vegetation and soil.

• Korean Journal of Environmental Biology
• /
• v.36 no.1
• /
• pp.50-61
• /
• 2018

The current study aimed to review the research trends on forest liming by age, country, and research topics, and seeks to summarize the effects of forest liming on soil, vegetation and water system in forest ecosystems. The recent goals of forest liming have been changed in response to changes in the acid deposition, and related studies have been mainly carried out in Europe and North America, where there is noted a massive forest decline, which was subsequently caused by acid rain. Most forest liming studies are noted to have focused on soil responses, however, the number of studies on the responses of vegetation and water system according to a literature review on the subject were relatively small. Meanwhile, forest liming influenced whole forest ecosystems through interaction between the soil, vegetation and water system as associated with the relevant regions. The changes in soil pH, base saturation, and cation exchange capacity by forest liming were noted as different depending on the soil layer and elapsed time after liming. The responses of vegetation to forest liming were shown in above- and below-ground plant growth and plant nutrient concentration, and also were noted to have varied depending on the available regional plant species and noted specific soil conditions. The chemical properties of the water system were changed similarly to those in the soil, leading to notable changes as seen in the planktons and available fish species in the region. Finally, these results could be used to plan further studies on forest liming, which would significantly benefit regional studies to promote the preservation of the species noted for protection in the region.

• Korean Journal of Environmental Agriculture
• /
• v.28 no.1
• /
• pp.15-19
• /
• 2009

Ammonia in atmosphere has a negative effect on the natural ecosystems, such as soil acidification and eutrophication, by wet and dry deposition. Livestock manure, compost, and fertilizer applications to arable land have been recognised as a major source of atmospheric ammonia emissions. The objective of this study was to evaluate the efficiency of compost application techniques in reducing ammonia loss in upland soil. The reductions in ammonia emission were 70 and 15% for immediate rotary after application (IRA) and rotary at 3 day after application (RA-3d) in comparison with surface application (SA). Total ammonia emissions for 13 days, expressed as % ammonia-N applied with compost, were 42, 35.7, and 12.7% for SA, RA-3d, and IRA treatments, respectively. The ammonia emission rate fell rapidly 6 h after application and 61 % of total ammonia emission occurred within the first 24 h following surface application. The lime application along with compost significantly enhanced the total ammonia emission. Total ammonia emission for 22 days were 40.1, 31.4, and 27.7 kg/ha for immediate incorporation in soil after lime and compost application, lime incorporation in soil following 3 days after compost surface application, and compost incorporation in soil following 3 days after lime surface application, respectively. Therefore, lime and livestock manure compost application at the same time was not recommended for abatement of ammonia emission in upland soil.

• Korean Journal of Soil Science and Fertilizer
• /
• v.37 no.6
• /
• pp.371-377
• /
• 2004

Sulfate adsorption in forest soils is a process of sulfur dynamics playing an important role in plant uptake, cation movement, acid neutralization capacity and so on. The relationship between sulfate adsorption and some physicochemical properties of four forest soils was investigated. Extractable sulfate contents and sulfate adsorption capacity (SAC) in the forest soils varied much among study sites. Extractable sulfate contents were more in sub-surface soils with lower organic matter and greater Al and Fe oxides than in surface soils. The average contents of $Al_d$ and $Fe_d$ in the sub-surface soils were 8.49 and $12.45g\;kg^{-1}$, respectively. Soil pH, cation exchange capacity and clay content were positively correlated with the extractable sulfate contents and SAC. Organic carbon content, however, was negatively correlated with the extractable sulfate contents, implying the competitive adsorption of sulfate with soil organic matter. Considerably significant correlation was found between inorganic + amorphous Al and Fe oxides and the sulfate adsorption, but crystalline Al and other fractions of Fe oxide showed no correlation. Relatively close relationship between the adsorbed sulfates and soil pH, cation exchange capacity, or amorphous Al oxides indicates that the accelerated soil acidification may substantially reduce the potential for sulfate adsorption contributing to sulfur flux in forest ecosystems.

• Korean Journal of Soil Science and Fertilizer
• /
• v.17 no.3
• /
• pp.253-257
• /
• 1984

A field experiment was conducted in order to secure the basic information on the rational application of nitrogen and potassium for autumn growing Chinese cabbage (Brassica campastris ssp. pekinensis, var.; Miho 70 days). The results of the experiment are summarized as follows: 1. Potassium effect was observed where nitrogen applied either less than 15kg N/10a and heavy dose of 25kg N/10a. No potassium effect was observed where 20kg N/10a applied. In the case of 25kg N/10a, potassium effect was observed only in total weight but failed yield marketable product weighing over 1 kilogram per cabbage. 2. Nitrogen application, in general, tends to lower the soil pH and it is particularly true when heavy dose of over 20kg N/10a is applied. As a result, Chinese cabbage has increasingly removed soil born potassium and reduced exchangeable potassium content of the soil. 3. Oven dried cabbage which received 25kg N/10a plus potassium showed a low concentration of calcium and this phenomena seems to be attributable to the acidification of soils and it further caused failure in producing cabbages of marketing value.

• Korean Journal of Soil Science and Fertilizer
• /
• v.36 no.4
• /
• pp.218-224
• /
• 2003

Magnesium hydroxide, which recently registered as a Mg fertilizer, is greatly different from magnesium sulfate in its solubility and effect on soil pH. In this study, the effects of magnesium hydroxide and magnesium sulfate on growth of chinese cabbage were compared at the application rate of $300kg\;MgO\;ha^{-1}$ in a Gyeongsan clay loam soil. Although magnesium hydroxide was effective in increasing number of leaf and fresh weight, overall effects of magnesium hydroxide and magnesium sulfate on the growth of chinese cabbage were not significantly different ($p{\leq}0.05$). Comparing the two magnesium fertilizer treatments, magnesium content of chinese cabbage was relatively higher in the magnesium sulfate treatment in the early stage of growth, but it was higher in the magnesium hydroxide treatment at harvest. Contents of Ca, P, and K in chinese cabbage were relatively higher in the magnesium hydroxide treatment than those in magnesium sulfate treatment. But, the differences in nutrient uptakes by chinese cabbage between the treatments were not significant ($p{\leq}0.05$). Therefore, magnesium hydroxide is expected to be used with nearly the same effects on crops as magnesium sulfate at the same application rate of Mg. Soil pH in the treatment of magnesium sulfate was lower than that of control treatment, but magnesium hydroxide could increase pH. Magnesium hydroxide can be used preferentially in acid and/or sandy soils, where magnesium sulfate can induce further soil acidification and leaching loss of Mg is often a severe problem.