• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.369-369
• /
• 2017

To improve the reclaimed land soil, we put organic materials (Chopped kenaf, decomposed rice hull, rice straw, pellet type manure compost) into reclaimed land for 3,000 kg per 10a. As a result, EC of reclaimed soil was lowered by 58% ($1.2dS/m{\rightarrow}0.5$), content of soil organic material was risen from 6.7 g/kg to 16.0 (1.4 fold ${\uparrow}$), porosity of soil was elevated from 1.57 % to 1.31 (16.6% ${\downarrow}$), soil hardness was reduced from 20.2 mm to 17.9 (11.4% ${\downarrow}$) and plow layer soil was deepen from 19.8 cm to 26.8 (35% ${\uparrow}$). In the wake of physiochemical improvement of reclaimed soil, the growth phase of crops became better contrast to non-treatment. For example the plant height of Kenaf (Hibiscus cannabinus L.) cultivated in reclaimed land containing organic materials was lengthen by 18.8%. Especially, the improvment effect of pellet type manure compost and rice straw was more preferable. When the kenaf was cultivated in reclaimed land containing organic materials, the yield was become higher. The average yield of organic materials treatment was 9,218 kg/10a, and it was 2.1 times higher than non-treatment (4,368kg/10a). And the effective treatments to increase yields were pellet type manure compost (10,848 kg/10a, 148% ${\uparrow}$), rice straw (120% ${\uparrow}$) and chopped kenaf (95% ${\uparrow}$). To intensify the effect of physicochemical enhancement of reclaimed land soil and improving yields, we put into various physical types of organic materials (pellet type, liquid type, powdered type). The most effective organic materials type for enhancement of physicochemical properties (EC of reclaimed soil was lowered, content of soil organic material was risen, porosity of soil was elevated, soil hardness was reduced, plow layer soil was deepen) was pellet. And source to maintain better growth phase and get more yield were liquid and pellet types. When we used pellet type organic material, the plant height of kenaf was lengthen by 41% in comparison with non-treatment and yield was more than 122% more. And also liquid type could get more yield (by 127%) and growth phase (by 38%)

• Journal of Environmental Science International
• /
• v.28 no.8
• /
• pp.655-667
• /
• 2019

This research aims to identify the possibility of developing A horizon resources that can be used for construction and civil engineering work. As such, the utility of A horizon resources was examined by establishing planting ground through a mixture of soil layers and by analyzing the growth and development of Pinus densiflora. The physicochemical and physical properties of the soil were as follows: the A horizon was sandy clay loam, B horizon was sandy loam, and the mixture of two layers appeared as sandy loam, which was identical to the B horizon. The experimental groups did not show any significant difference in their physical properties of porosity and degree of water-stable aggregates. With regards to chemical properties, the A horizon as well as the mixture of A and B horizon showed acidity while the B horizon showed alkalinity. The figures of organic matter, total nitrogen, available phosphate, and replaceable potassium were greater as the A horizon content increased, whereas the figures of replaceable calcium, replaceable magnesium, and conductivity increased as the A horizon content decreased. As a result of the growth and development of Pinus densiflora in each planting ground, the final survival rates were all above 100%. However, the tree height and the rate of growth for the diameter of root were higher in the order of A horizon > A horizon + B horizon > B horizon,indicating that the increased A horizon content is related to the growth and development of Pinus densiflora. The treatment of soil with improvement agents, used to recover the functions of in-situ soil showing poor growth and development, did not have a clear impact on the soil texture and porosity. However, the degree of water-stable aggregates increased significantly when using O horizon as the soil improvement agent among the types of in-situ soil. In contrast, all items related to the chemical properties showed significant differences following the treatment by soil improvement agents. The survival rate according to the treatment of soil improvement agents for the growth and development of Pinus densiflora was higher in the order of organic horizon = no treatment > compound fertilizer > organic fertilizer + compound fertilizer > organic fertilizer; this result was statistically significant with a marginal significance value of the log-rank test(p < 0.05).

• Journal of Microbiology and Biotechnology
• /
• v.30 no.11
• /
• pp.1688-1696
• /
• 2020

Soil physical and chemical characteristics, soil potential denitrification rates (PDR), community composition and nirK-, nirS- and nosZ-encoding denitrifiers were studied by using MiSeq sequencing, quantitative polymerase chain reaction (qPCR), and terminal restriction fragment polymorphism (T-RFLP) technologies base on short-term (5-year) tillage field experiment. The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue retention (NT), and rotary tillage with crop residue removed as control (RTO). The results indicated that soil organic carbon, total nitrogen and NH₄⁺-N contents were increased with CT, RT and NT treatments. Compared with RTO treatment, the copies number of nirK, nirS and nosZ in paddy soil with CT, RT and NT treatments were significantly increased. The principal coordinate analysis indicated that tillage management and crop residue returning management were the most and the second important factors for the change of denitrifying bacteria community, respectively. Meanwhile, this study indicated that activity and community composition of denitrifiers with CT, RT and NT treatments were increased, compared with RTO treatment. This result showed that nirK, nirS and nosZ-type denitrifiers communities in crop residue applied soil had higher species diversity compared with crop residue removed soil, and denitrifying bacteria community composition were dominated by Gammaproteobacteria, Deltaproteobacteria, and Betaproteobacteria. Therefore, it is a beneficial practice to increase soil PDR level, abundance and community composition of nitrogen-functional soil microorganism by combined application of tillage with crop residue management.

• Journal of Environmental Science International
• /
• v.22 no.1
• /
• pp.17-23
• /
• 2013

In order to evaluate the effect of various organic soil conditioner ratios on the soil moisture content and growth of Cotoneaster horizontalis, a container type for wall-planting experiment was conducted in a greenhouse at Konkuk University under non-irrigation. The experimental planting grounds were prepared with different organic soil conditioner ratios ($A_1L_0$, $A_8L_1$, $A_4L_1$ $A_2L_1$ and $A_1L_1$), and a drought-tolerant ornamental variety of Cotoneaster horizontalis was planted. The change in soil moisture content, plant height, number of branches, number of dead leaves, number of leaves, number of shoots, length of node, length of leaf, width of leaf, root-collar caliper, chlorophyll content, and survival rate were investigated, from April to Jun 2010. The results of soil moisture content measurements were analyzed with weight units in the container type for wall-planting during the dry summer season. The soil moisture contents were significantly enhanced in the container type for wall-planting in increasing order as the amount of soil conditioner level was increased ($A_1L_1$ > $A_2L_1$ > $A_4L_1$ > $A_8L_1$ > $A_1L_0$). Compared to the control treatment application (amended soil with 100% + organic soil conditioner 0%), the highest plant growth was observed in the treatment of $A_1L_1$ application (amended soil with 50% + organic soil conditioner 50%). However, the differences between the organic soil conditioner ratio treatments of $A_1L_1$, $A_4L_1$, and $A_8L_1$ organic soil conditioner application were mostly not significant. The survival rate increased with the increasing application of organic soil conditioner, but in the control treatment application all the plants died. The experimental results from clearly demonstrated that the organic soil conditioner improved the survival rate more than the growth of Cotoneaster horizontalis. Therefore, Cotoneaster horizontalis is expected to be a highly valuable shrub for green wall systems, when considered for us in integration system or for increasing soil water contents in planting grounds.

• Korean Journal of Soil Science and Fertilizer
• /
• v.26 no.2
• /
• pp.78-84
• /
• 1993

In order to know the effect of sludge from water treatment plants un agricultural environment, an experiment of water treatment sludge application for Altari radish (Raphanus sativus L.) was carried out. And the results were as follows ; 1. The pH of water treatment sludge was 7.2, which was higher than that of the experimental soil. The exchangeable Ca content in the sludge was very high being 29me/100g sludge. So when the sludge was applied to the soil, amending effect for soil acidity was supposed. 2. With the application of the water treatment sludge to the soil, soil pH and organic matter content were increased. With the increase of the level of sludge application, contents of crude fiber and Ca in Altari radish were increased, white those of P and Mg tended to decrease. 3. The length of the root and the amount of fresh yield of the whole plant of radish tended to increase with the increase of sludge application, and this tendency was more evident on the infertile soil. From the above results, it was concluded that the fresh yield of Altari radish increased up to 75ton/ha sludge application on the fertile soil, but the yield decreased when higher levels of sludge was applied. While on the infertile soil, the yield increased up to the application of 300ton/ha, and the heavier application level did not adversely affect the yield of Altari radish.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2005.10a
• /
• pp.122-122
• /
• 2005

The remediation for contaminated soil and groundwater in contaminated site and waste site has to be compact and economic in maintaining and operating the system. In this study, the atomized slag was tested if they are an effective reactive material in permeable reactive barrier This novel reactive system technology was applied to the treatment of leachate from unplanned waste landfill. The system was optimized and developed to be commercialized.

• Korean Journal of Soil Science and Fertilizer
• /
• v.49 no.2
• /
• pp.194-199
• /
• 2016

In an experiment conducted at the research field of the National Institute of Agricultural Science, we investigated the effects of mineral fertilizer and rice straw compost on exchangeable potassium and K balances, and rice grain yield under a rice single system. The treatments were no fertilization (No fert.), inorganic fertilization (N), inorganic fertilizer (N, P, K) plus rice straw compost at rates of 7.5, 15.0, 22.5, and $30.0ton\;ha^{-1}$ (NPKC7.5, NPKC15.0, NPKC22.5, and NPKC30.0, respectively). The inorganic fertilizers(N, P, K) were added with standard fertilizer application rate in which nitrogen (N), phosphate ($P_2O_5$), and potassium ($K_2O$) were applied with $75{\sim}150kg\;ha^{-1}$, $70{\sim}86kg\;ha^{-1}$, $75{\sim}86kg\;ha^{-1}$, respectively. Exchangeable potassium for NPKC15.0 NPKC22.5, and NPK30.0 treatments was higher by $0.05{\sim}0.19cmol_c\;kg^{-1}$ than that of NPKC7.5 treatment. Increasing levels of rice straw compost resulted in an increase in the K balance from - $19.9kg\;ha^{-1}yr^{-1}$ (No fert.) to $41.9kg\;ha^{-1}yr^{-1}$ at NPKC22.5 treatment and $62.9kg\;ha^{-1}$ at NPKC30.0 treatment. Continuous application of rice straw compost with NPK fertilizers affected significantly the rice grain yields. The result of the study imply that the application of more than $22.5ton\;ha^{-1}$ of rice straw compost with NPK fertilizers are recommended as the best fertilization practice for enhancement of crop production and K supplying power of soil in the continuous rice cropping system.

• Journal of Environmental Science International
• /
• v.19 no.1
• /
• pp.17-26
• /
• 2010

To understand the initial changes in the microbial activities of wetland soil after construction, dehydrogenase activity (DHA) and denitrification potential (DNP) of soil from 1 natural wetland and 2 newly constructed wetlands were monitored. Soil samples were collected from the Daepyung marsh as a natural wetland, a treatment wetland in the West Nakdong River, and an experimental wetland in the Pukyong National University, Busan. The results showed that the DHA of the natural wetland soil was 6.1 times higher than that of the experimental wetland and similar to that of the treatment wetland 6 months after wetland construction (fall). Few differences were observed in the DNP between the soil samples from the natural wetland and 2 constructed wetlands four months after wetland construction (summer). However, 6 months after the construction (fall), the DNP of the soil samples from the natural wetland was 12.9 times and 1.8 times higher than that of the experimental wetland and the treatment wetland, respectively. These results suggested that the presence of organic matter as a carbon source in the wetland soil affects the DHA of wetland soil. Seasonal variation of wetland environment, acclimation time under anaerobic or anoxic wetland conditions, and the presence of carbon source also affect the DNP of the wetland soil. The results imply that the newly constructed wetland requires some period of time for having the better contaminant removal performance through biogeochemical processes. Therefore, those microbial activities and related indicators could be considered for wetland management such as operation and performance monitoring of wetlands.

• Korean Journal of Soil Science and Fertilizer
• /
• v.46 no.3
• /
• pp.209-215
• /
• 2013

This study was conducted to investigate the effects of boron treatments on flower spike dieback of Statice (Limonium spp.) grown in soilless hydroponic and soil cultures under rain shelter system. The growth of Statice was gradually improved with increasing boron applications in the hydroponics, but not in soil culture with boron treatment as foliar spray or soil application. The degree of flower spike dieback in 6 levels (0, no dieback incidence to 5, very severe dieback incidence) ranged between 0.5 with boron application and 4.4 with no boron treatment. The content of boron in Statice flower spike increased with increasing rates of boron applications in the hydroponics, but the contents of P, Mg, and N were not affected by the boron application. However, K content was highest with no boron treatment. In soil culture, incidence of flower spike dieback decreased with foliar spray or soil application of boron. Therefore, boron application was effective in reducing flower spike dieback and improving cut-flower productivity and its quality, and the recommended rates of boron application were $50{\sim}80{\mu}gL^{-1}$ for hydroponics culture whereas 0.2% borex or ${\geq}0.4kg\;10a^{-1}$ boric acid by foliar spray application for soil culture.

• Korean Journal of Medicinal Crop Science
• /
• v.28 no.6
• /
• pp.412-420
• /
• 2020

Background: Measurement of chlorophyll fluorescence (CF) is useful for detection the ability of plants to tolerate environmental stresses such as drought, and excessive sunlight. Cnidium officinale Makino is highly sensitive to water stress and excessive sunlight. In this study, we evaluated the effect of soil water and shade treatment on the photosynthesis and leaf temperature change of C. officinale. Methods and Results: C. officinale was cultivated under uniform irrigation for 1 week drought stress (no watering) for 6 days. A significant decrease in CF was observed on the 5th day of withholding water (approximately 6% of soil water content) regardless of shading. Notably, the Rfd_lss parameter (CF decrease rates) with and without shade treatment was reduced by 73.1% and 56.5% respectively, at 6 days compared with those at the initial stage (0 day). The patterns of the degree of CF parameters corresponded to those of the soil water content and difference between leaf temperature (Ts) and air temperature (Ta). Meanwhile, CF parameters recovered to the 3 - 4 days levels after re-watering, while the soil water potential was completely restored. The suitable soil water content for C. officinale optimal growth was between -5 kPa and -10 kPa in this experiment. Conclusions: Lack of soil water in the cultivation of C. officinale, even with shading, decreased latent heat cooling through transpiration. As a result, heat dissipation declined, and the plant was subjected to drought stress. Soil water content plays a major role in photosynthesis and leaf temperature in C. officinale.