• Korean Journal of Soil Science and Fertilizer
• /
• v.20 no.2
• /
• pp.153-159
• /
• 1987

Adsorption and desorption characteristics of $^{42}K$ and $^{45}Ca$ were studied by making use of the natural zeolite, bentonite, and vermiculite. The work included that the fittness tests for the Freundlich and the Langmuir adsorption isotherms and desorption of the radionuclides from adsorbents by extracting with $NH^+_4$ ($1N-NH_4OAc$). The adsorption by the radionuclides are fitted well with both of the adsorption equations. The Langmuir adsorption maximum of $^{42}K$ is higher than that of $^{45}Ca$ by the zeolite and bentonite except vermiculite, and the values of $^{42}K$ decrease in the order of Zeolite (Zt)>Bentonite (Bt)>Vemiculite (Vt). As for $^{45}Ca$, the maximum adsorption values decrease in the order of Bt>Vt>Zt. The ionic radii of K and Ca seem to be closely related with fixation in the cavity of the zeolite that adsorb more $^{42}K$ than $^{45}Ca$. The smaller ionic size of Ca seems to be resulted in the lower adsorption of $^{45}Ca$ by the zeolite because Ca could leave easily from the cavity. Ionic size of K, however, seems to be similar with size of the cavity. $^{45}Ca$ adsorption by the bentonite, on the other hand, show higher adsorption than $^{42}K$. The higher charge density of the divalent cations than those of the monovalent cations seems to be the main consideration. For the retention strength of the adsorbed $^{42}K$ and $^{45}Ca$ by the adsorbents, a comparison is made by use of the Langmuir constant(k). The results indicated that the constant values for K are smaller than those of Ca in all the adsorbents. It seems that the smaller values of the constant, the weaker retention strength. For $^{42}K$, the percentage of desorption decrease in the order of Zt>Bt>Vt, but in the case of $^{45}Ca$, it decreases in the order of Vt>Zt>Bt. The results show that the weaker binding strength as represented by small value of the Langmuir constant, the higher percentage of the removal except fixing preferably $K^+$ by the vemiculite. In conclusion, the zeolite could adsorb much more $^{42}K$ and remove it more than others. For $^{45}Ca$, the bentonite could adsorb more and desorb less than others.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.3
• /
• pp.13-20
• /
• 2005

This study was conducted to suggest the ecological restoration methods of the decomposed granite cut-slope by organic soil amendment materials. Field test carried out for the cut-slope with organic soil amendment materials method and other three revegetation methods in Cheongwon. Test revegetation plants were Festuca arundinacea, Lolium perenne, Dactylis glomerata, Lespedeza cyrtobotrya, and Arundinella hirta. The result of this study can be summarized as follows; 1. The soil hardness, the soil acidity, and the soil humidity of organic soil amendment materials method were at a suitable value for plants growth. And it was better as compared with other three revegetation methods of cutting-rock slopes. 2. The result of toxic substance investigation, all items were at a suitable for standard law. 3. During one year after seeding, most plants germinated and especially Festuca arundinacea and Dactylis glomerata grows well. Seedling numbers were 336.7 per $m^2$(after 6 months), 183.3 per $m^2$(after 10 months), and 353.3 per $m^2$(after 6 months). Ten months later after seeding, plants showed 80% ground coverage. Visual rate, plant height, and growth rate were excellence, Also, high plant growth in spring better than autumn.

• Journal of Environmental Science International
• /
• v.24 no.11
• /
• pp.1363-1370
• /
• 2015

This study was aimed to determine effects of soil organic amendment as plant growing media component on restoration of planting ground. The changes of soil physical and chemical properties and germination and growth of kentucky bluegrass (Poa pratensis L.) were investigated. For treatments, soil was excavated at depth of 0-50 cm (referred as $S_1$) and at depth of 50-100 cm (referred as $S_2$). Then the half amount of $S_1$ soil was mixed with the soil organic amendment (coir dust 40% (v/v), bottom ash 25%, leaf mold 25%, vermiculite 5%, carbonized rice hull 5%) at a rate of 6% (v/v) (referred as $S_1CC$) and also the half amount of $S_2$ soil was mixed with the soil organic amendment at a rate of 6% (v/v) (referred as $S_2CC$) on pot in a 16 cm diameter and 14 cm height. The experiment was replicated 3 times with 3 pots per replication in randomized block design, and 100 seeds were planted per pot. In results, there was no significant difference in soil pH among the treatments with a slight decrease in soil hydraulic conductivity. However, in the $S_1CC$ treatment, positive increases in soil chemical properties, including electrical conductivity, organic matter, phosphoric acid, total nitrogen, exchangeable cation, and cation exchange capacity. Also, the germination rate, plant height, and number of leaves were higher in the $S_1CC$ treatment than those in other treatments. These results suggest that the addition of organic amendment to the soil at depth of 0-50 cm might be proper for restoring planting ground.

• Journal of the Korean GEO-environmental Society
• /
• v.14 no.6
• /
• pp.39-46
• /
• 2013

The field of ground amelioration, many construction methods have been developed more prosperously up to now, but even now, the majority focuses on the improvement of ground strength. And they could not suggest concrete solutions to the occurrence of environmental issues. To address this problem, soil improvement methods employing organic acid materials have recently been developed as eco-friendly technologies for increasing the soil strength, but details regarding the basic stabilization mechanism are not known yet. Against this background, this research was conducted to examine the soil stabilization mechanism; for this purpose, unconfined compressive strength and pH tests were conducted by using an improved eco-friendly organic acid material. The test results revealed that the samples processed with the organic acid showed a considerable increase in the unconfined compressive strength over time as compared to the strength of the samples that were processed without the organic acid. It was also confirmed that the organic acid material promoted microbial breeding and improved the soil structure by reducing the volume of the voids in the soil. Therefore, the sustainable development of this method needs to be analysed more in the future.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.14 no.2
• /
• pp.21-32
• /
• 2011

The effects of high polymer on the seedling survival were investigated in three major turfgrasses. Twelve treatments were used in the study with different rates of sand, soil organic amendment (SOA), and water-swelling polymer (WSP). Turfgrass seedling survival rate was evaluated in creeping bentgrass (CB), Kentucky bluegrass (KB), and zoysiagrass (Zoy) grown under greenhouse conditions. Significant differences were observed among the treatments. Seedling survival rates were variable in CB, KB, and Zoy according to mixing rates of SOA and WSP, being maximum 20.2% in differences. At 6 weeks after seeding, the survival rates ranged from 0.6 to 61.9% in CB, 4.2 to 75.3% in KB and 1.7 to 82.1% in Zoy. A pattern of seedling emergence varied with time among treatments influenced by WSP rates. A proper mixing rate of WSP is considered to be 5% for CB and 5 to 10% for KB and Zoy. In general, overall effect of WSP on seedling survival was clearly observed in the mixtures of sand 80% and SOA 20% in CB. The best result, however, was found from the mixture of sand 85% and SOA 15% in both KB and Zoy. When mixing sand with WSP, a proper rate of SOA is considered to be 20% for CB and 15 to 20% for KB, while 10 to 15% for Zoy. A further research is needed to investigate the effects of WSP on the turf quality in mixtures of sand, SOA, and WSP before a field application.

• Korean Journal of Environmental Agriculture
• /
• v.21 no.2
• /
• pp.96-101
• /
• 2002

This study was conducted to survey and identify kinds and population of the freshwater invertebrate fauna according to the managements of paddy rice fields at Ok-Chun and Yang-Pyung. The experiment was conducted in 4 paddy plots; conventional fertilization plot (CF), fertilization by prescription with soil testing with (ST+A) or without soil amendment (ST), and no fertilization as the control. In addition, the freshwater invertebrate fauna was also surveyed at 3 sections of as upper, intermediate and down, in both Jitan and Bungsan stream. The total number of the freshwater invertebrates was higher in the order of ST>CF>ST+A>C and ST>ST+A>CF>C at Ok-Chun and Yang-Pyung, respectively. The population density of aquatic insects was higher in plots fertilized by prescription with soil testing than in the other plots at both demonstration villages. The freshwater invertebrates collected in Jitan and Bungsan stream were identified and classified into 59 families and 90 species, and their population density was highest in the downstream among.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.2 no.1
• /
• pp.1-9
• /
• 1999

To find pertinent soil type and maintenance method for artificial planting ground, the effects of soil compositions{sandy loam(S), vermiculite(V), sandy loam+vermiculite+sand(SVS), sandy loam+ carbonized rice husk+sand(SCS), sandy loam+humus sawdust+sand(SHS)}, and fertilizers (organic, chemical) on plant(kentuckyblue grass) growth were measured and compared from the field experiment. The results are summarized as follows 1. the highest germination rate is found from "vermiculite(V)" and the lowest from "sandy loam(S)" among tested 5 soil compositions. 2. "sandy loam+vermiculite+sand(SVS)" composition shows the highest plant height growth effect (5cm growth during tested 3 months) comparing to other 4 compositions. 3. "sandy loam+vermiculite+sand(SYS)" composition shows the highest ground covering rate after first two months, but it concede its order to "sandy loam+humus sawdust+sand(SHS)" composition after next one month growing. 4. the effects of fertilizers are follows 1) Among the blocks where no fertilizer was tried, the predominant height growth was obvious in "sandy loam+carbonized rice husk+sand(SCS)" and "sandy loam+humus sawdust+sand(SHS)" composition. 2) Among the blocks where chemical fertilizer was tried, relatively positive results were found from "vermiculite(V)" and "sandy loam+vermiculite+sand(SYS)" blocks on germination and growth rate. But on the ground coverage ratio, the effect of "sandy loam+carbonized rice husk+sand(SCS)" composite precede that of those 2 composites. 3) Among the blocks where organic fertilizer was tried, "sandy loam+humus sawdust+sand(SHS)" and "vermiculite(V)" blocks show relatively high ground coverage rate, growth rate than others. 4) When compositional differences were not considered, the block where organic fertilizer was tried shows most positive effects on all 3 measurements-germination ratio, height growth and ground covering.

• Geotechnical Engineering
• /
• v.11 no.2
• /
• pp.99-106
• /
• 1995

Although lots of experimental studies of coal ash have been performed to study the utilization as construction materials, the environmental characteristics of coal ash are still qestionable. In this study, fly ash is examined to be classified according to Korean Environmental Standard and analized whether the batch test results are within the toler trance limit when utilized or treated as reclamation and earth work materials. The batch tests was performed to examine pH and contaminant contents. Consequently, fly ash is classified as non hazardous industrial waste. The pH value shows a strong alkalinity than the tolerance limit, but it is implied that fly ash can be used to neutralize the acid ground. All other items except pH satisfy the tolerance limit, In addition, a small quantity of additives(cement) which used to improve the poor geotechnical properties of coal ash, could decrease the pH value into the tolerance limit as well as improve strengtIL durability and permeability. It is concluded that when coal ash is used properly, there is no enviormental harmfulness as construction materials.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.30 no.3
• /
• pp.86-93
• /
• 2002

The objectives of this research were to investigate the effect of serpentine as a new soil conditioner for growth of turfgrass. To achieve the goal, pure sand or mixtures of sand and serpentine with various ratios were tested for soil physical properties and the growth effects of perennial ryegrass and zoysiagrass growth were compared. Major results of this research are summarized as follows; 1) Hydraulic conductivity of 10~30% serpentine mixtures were observed within the range of 1010~901mm/h which is good for USGA recommendation. Experimental results of pH and EC for various mixtures indicated that the 10% serpentine mixture was the most suitable for turfgrass growth. 2) Perennial ryegass treated with 10% serpentine mixture showed the highest visual quality(p<0.01) among all treatments. And serpentine treatment was more effective to improve visual quality of perennial ryegrass than that of zoysiagrass. The treatment of 10% serpentine had better visual qualities than that of 20% in both of zoysiagrass and perennial ryegrass. Treatment with the right amount of serpentine extends green period for one to two weeks during early winter in both zoysiagrass and perennial ryegrass. 3) In perennial ryegrass, the treatment of 10% serpentine resulted in an increase of total dry weight compare with those of zeolite or barley stone, and also dramatically promoted the dry weight by 15% compared with sand 100%(control). Total dry weight of zoysiagrass treated with 10% serpentine was 9％ higher than that of san. These results indicated that serpentine can be a good soil conditioner for both zoysiagrass and perennial ryegrass when it is blended with sand within a range of 10 to 20% by volume.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.18 no.3
• /
• pp.1-11
• /
• 2015

This research was conducted to compare the effect of soil amendment and loess on physial and chemical properties of dredged soil and primary height growth of Ulmus davidiana var. japonica. Three types of research plots: control plot (Dredged soil only), DC treatment plot (Dredged soil + soil amendment) and DCL treatment plot (Dredged soil + soil amendment + Loess) were set at Okgu research site in Saemanguem. 32 trees of U. davidiana var. japonica were planted in each plots after 14 months from the construction. Soil texture, pH, electrical conductivity (EC), organic matter (OM), total nitrogen (TN), available P, exchangeable cation ($K^+$, $Na^+$, $Mg^{2+}$, $Ca^{2+}$) and sodium chloride were measured after 3 years from the construction. Also, survival rate and height of U. davidiana var. japonica were measured 22 months after planting, and the correlation between height of trees and the physico-chemical properties of soil were analyzed. Even though pH in both DC and DCL treatment plots are lower than control plot, they are still alkaline (> pH 8). OM, TN and available P in both DC and DCL treatment were higher than the control. Particularly, the content of available P in both DC and DCL treatment plots are 1.4~5.1 times and 2.0~3.1 times higher than the control respectively. The concentration of exchangeable Mg in DCL treatment plot was 1.1~5.5 times higher than the control (p < .05). The survival rate of the species was the highest in DCL treatment plot (98%) followed by DC treatment plot and the control. The average height of the trees in both DC and DCL treatment plots is 1.1m while the control is 0.8m. OM, TN, available P, K+ were significantly related to the height of U. davidiana var. japonica(p < .01). The results indicate that soil amendment affects on soil physial and chemical properties of dredged soil and height growth of U. davidiana var. japonica.