• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.6
• /
• pp.34-44
• /
• 2005

The objective of this study is to analyze the thermal properties of various green roof type. The experimental districts, have different soil thickness, soil type, the existence of module and the different kinds of vegetation, had installed. A measurement was conducted in Seoul University to investigate the thermal impacts of rooftop greening. The measurement point of temperature were 30, located in soil surface, middle of the soil layer, under the module, hard surface and soffit surface of each experimental district. The experimental investigation lasted from 6th August to 29th August, a total of 24 days. The results showed that green roof can contribute thermal benefits by soil and vegetation and reduce building energy consumption by a role of insulation. It's also better to make soil thickness over 20cm and various vegetation that should be more effective. The district installed only soil also could be effective for reducing the temperature of roof surface. Therefore, the increase of soil thickness and various vegetation could reduce more temperature of roof surface and building energy consumption. Also, it's helpful to reduce temperature that plant coverage rate be raised.

• Journal of Environmental Impact Assessment
• /
• v.19 no.3
• /
• pp.231-245
• /
• 2010

The the purpose of this study was to analyze of the vegetation structure and phytosociological changes in the area adjacent to GeumJeong Mountain Fortress for fifteen years. The result of this study was as follows; Of the 8 quadrates, site of the North Gate 2 was having a highest in the number of extinct trees, 15 kinds. This is probably due to trampling effect caused by climbers' steps. Site of the West Gate 1 and South gate 1 each had 8 kinds of extinct trees, respectively. The number of newly appeared trees was highest at site of the North Gate 1, (8 kinds) followed by the sites of South gate 1 and South gate 2, respectively (5 kinds). The highest decrease in number of tree species was observed in North Gate 1, therefore, there is a strong relationship between vegetation diversity and the number of users of the available spaces. In order to revitalize the unstable vegetation structure of the Area Adjacent to GeumJeong Mountain Fortress, Robinia pseudo-acacia has to be well maintained in the shrub tree layer, and vines, such as Smilax china, Humulus japonicus, and Pueraria thungergiana, should be removed. To recover natural vegetation, dead leaf layer should be protected, and more shrub trees need to be planted. In the understory and shrub tree layer, multi layer tree planting is highly recommended to recover natural vegetation and increase tree diversity. In order to improve bad soil condition caused by trampling effect of recreational users, special treatments to the soil structure are required, such as mulching and raking soil. Also, depending on its soil damage from users trampling, the areas in the park should be divided into usable areas and user limited areas by the sabbatical year system. To improve the soil acidity due to acidic rain, soil buffering ability should be improved by activating microorganisms in the soil by using lime and organic material.

• Korean Journal of Ecology and Environment
• /
• v.44 no.1
• /
• pp.42-57
• /
• 2011

We described the above-ground plant species composition and measured a range of soil physico-chemical properties and the composition and size of the soil seed bank in the remnant natural vegetations on the flood plains of the Han River within Seoul, South Korea. We used analysis of variance and multivariate analyses to analyse the data and S${\o}$rensen's similarity index to compare the composition of the vegetation and seed banks. The soils were circum-neutral and composed of mainly sand and silt fractions with a very limited clay component; a gradient based on sand/clay proportions was identified. The soil seed banks varied markedly between- and within-sites and had much greater species diversity than the above-ground vegetation. Two of the major dominants in the vegetation (Miscanthus saccariflorus and Phragmites australis) were found at very low densities in the seed bank. The site differences appeared to be correlated with the sand-clay gradient, suggesting that the soil properties differentially affected seed inputs into the soil, or that the processes than controlled sediment deposition during floods was also important in differentially affecting seed deposition. Lastly, there was relatively little similarity between the vegetation, dominated mainly by perennials, and the seed bank which contained a relatively large proportion of annuals and biennials. This result suggests that after disturbance caused by flooding there is the potential for many other species to colonize. This may impinge on the regeneration potential of the sites and cause concern for the future conservation of these important remnants of natural vegetation.

• The Korean Journal of Ecology
• /
• v.20 no.2
• /
• pp.145-151
• /
• 1997

A census of the forest vegetation of Mt. Kaya National Park was taken with respect to the medthods of ordination and classification. Eight groups were classified by cluster analysis : Quercus mongolica, Q. mongolica-Sasa borealis, Q. serrata, Q. variabilis, Carpinus laxiflora, Cornus controversa, Fraxinus mandshurica and Pinus densiflora. Among them, the Q. mongolica group and Q. mongolica-S. borealis group, the F. mandshurica group and C. controversa group showed similar floristic compositions to each other. The interrelationship between the floristic compositon of the vegetation and soil environment was analyzed by PCA, the Q. mongolica group and the Q. mongolica-S. borealis group were distributed in areas of high CEC and total nitrogen content, while the Q. serrata. Q. variabilis. C. laxiflora and Pinus densiflora groups formed their communities in the more moderate areas of pH, soil moisture and soil organic matter. F. mandshurica and C. controversa groups were distributed in the areas of high soil moisture, soil organic matter, pH and available phosphate.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.10 no.6
• /
• pp.99-109
• /
• 2007

The main objectives of this comparative study were 1) to compare the floristic similarity of species composition between the extant vegetation and seedlings from soil seed bank and 2) to quantify the potential contribution of soil seed bank to revegetation of forest in a constructed area, which is called "ecological impact mitigation" in conjunction with the power plant extension. Forest topsoil of seven plots was collected from the surface soil after measurements were taken on the ground vegetation in each plot. A greenhouse experiment was conducted and monitored to analyze the germination potential of soil seed bank. The forest topsoil was spread on plastic trays ($0.7m^2{\times}7$) filled with a 5cm layer of sterilized potting mix. The results of monitoring for 2 years in a greenhouse were as follows : 1) seedlings of soil seed bank per 4.9$m^2$ were 1,269 with 36 species (1st year) and 2,615 with 25 species (2nd year). 2) 38${\pm}$8% of the flora species were germinated from soil seed bank. It can be concluded that the use of soil seed bank would be effective to promote establishment of diverse species and vegetation. However, it behooves to continue monitoring on succession of vegetation and pursue revegetation with other methods for ecological restoration. Finally, adequate topsoil deposit and gathering methods should be studied properly.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.19 no.2
• /
• pp.121-135
• /
• 2016

The present study is an analysis of the monitoring results of the four areas that underwent the experimental construction of Straw-net+seedspray, Vegetation media spray method(t=2cm), and Vegetation media spray method(t=3cm), with the purpose of selecting the adequate revegetation of cutting slopes in weathered granite soil. Cutting slopes are mostly designed in the Straw-net+seedspray method, but since weathered granite soil slopes tend to have an infertile soil quality that runs down, it is difficult for seed germination and growth. It is difficult to apply Straw-net+seedspray to weathered granite soil slopes considering the germination rate and coverage rate of the Straw-net+seedspray method, which accompanies erosion and scouring. The final conclusions are summarized as follows. First, Straw-net+seedspray has difficulty recruiting plants to infertile weathered granite soil, which results in a lower coverage rate and fewer species, so it is not adequate construction method. Second, Vegetation spraying methods with wet media are more advantageous in early revegetation. The wet construction methods are faster than the dry construction methods in terms of early germination and its early growth are more excellent. Third, when constructing Vegetation spray methods with dry media, it were more advantageous if the thickness was thicker. When the soil-media is thicker, the soil is resilient to droughts, so the thickness must be flexibly applied according to the soil quality and slant of the weathered granite soil slope. The present study is a monitoring result for some areas of Gangwon-do, so its results may differ from other areas.

• Journal of Environmental Science International
• /
• v.31 no.3
• /
• pp.247-254
• /
• 2022

This study investigated the effect of vegetation mat on plant growth and salt reduction in the soil treated with high concentration deicing salt. In order to measure soil chemical characteristics and plant growth, three native groundcover plants (Dendranthema zawadskii var. latilobum, Dendranthema boreale, and Kalimeris yomena) were grown in each of the three plastic containers (50.0 cm width × 35.0 cm length × 8.5 cm deep) with a high concentration treatment of calcium chloride deicing salt. There were two treatments: control, and BVM that combines B (blanket) and VM (vegetation mat). 1,600 g of soil was placed on the top of the drainage layer with 290 g of perlite, 100 seeds each of the three native plants with three repetitions were sowed, and 10 g/L of calcium chloride deicing salt was added in the treatment. As a result of the chemical properties of soil, soil in control treatment was acidic and soil electrical conductivity in BVM was the lowest. Also, exchangeable cations (K⁺, Ca²⁺, Na⁺, and Mg²⁺) in soil and all the three plants were significantly decreased in the BVM treatment. Meanwhile, the germination rate of Dendranthema zawadskii var. latilobum was the highest under high concentration deicing salt in compared to the two plants. Overall, three native groundcover plant growth was higher in the BVM than control treatment significantly. These results suggest that the treatment of blanket vegetation mat has a positive effect on soil and plant growth in soil damaged by deicing salt.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.11
• /
• pp.5956-5963
• /
• 2013

By the activation of environment-friendly river works, application of vegetation mats is increasing, however, evaluation techniques for hydraulic stability of vegetation mats are not presented. This study is conducted to develop the objective test method for vegetation mats. Two kind of vegetation mats are tested by the real scale experiments, and hydraulic quantities are measured and analyzed to evaluate acting shear stresses. To evaluate soil loss, Terrestrial 3D LiDAR measurement is conducted and soil loss index are calculated from changes of bed elevation. Quantified evaluation for permissible shear stresses is conducted by graphical method for acting shear stresses and soil loss index. By the results of precision survey, changes of sub soil are limited to local range in stable cases and relatively large changes of sub soil which is similar to natural river bed are detected in unstable cases. From the study, evaluation of permissible shear stresses by ASTM D 6040 is avaliable in the failure mechanism and failure criteria by soil loss index.

• Journal of Forest and Environmental Science
• /
• v.37 no.4
• /
• pp.280-291
• /
• 2021

The study examined the influence of climate and soil dynamics on vegetation health across the ecological zones in Rivers State, Nigeria. MODIS imagery was used to assess the vegetation health through NDVI and point grid pattern of meteorological data for total precipitation (TP), air temperature (AT), soil moisture (SM) and soil temperature (ST) of 2000, 2003, 2006, 2009, 2012 and 2015 were used for the study. Descriptive and inferential statistics were used for data analysis. Findings showed that NDVI ranged between 0.420 and 0.612 in the freshwater swamp (FWS) while between 0.465 and 0.611 in the rainforest and the NDVI in the mangrove was generally low. The highest mean AT was experienced in the mangrove ecological zone and the least was experienced in the rainforest. The mean SM was generally highest in the rainforest with highest value in 2000 (774.44 m³/m³). The ST was highest in the mangrove and the least was experienced in the rainforest while the TP was highest in the mangrove. NDVI correlated significantly with SM (r=0.720; p<0.05) and ST (r= -0.493; p<0.05). NDVI, SM, TP and ST significantly varied among the ecological zones. Regression analysis showed that vegetation health was significantly related to the combination of soil temperature and soil moisture (R²=0.641; p=0.000). Thus, monitoring the factors that affect vegetation health in a changing climate and soil environments is highly required.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.234-238
• /
• 2008

The energy conservation theory is introduced for investigating processes of runoff and soil erosion on the hillslope system changed vegetation condition by wildfire The rainfall energy, input energy consisted of kinetic and potential energy, is influenced by vegetation coverage and height. Output energy at the outlet of hillslope is decided as the kinetic energy of runoff and erosion soil, and mechanical work according to moving water and soil is influenced dominantly by the work rather than the kinetic energy. Relationship between output and input energy is possible to calculate the energy loss in the runoff and erosion process. The absolute value of the energy loss is controlled by the input energy size of rainfall because energy losses of runoff increase as many rainfall pass through the hillslope system. The energy coefficient which is dimensionless is defined as the ratio of input energy of rainfall to output energy of runoff water and erosion soil such as runoff coefficient. The energy coefficient and runoff coefficient showed the highest correlation coefficient with the vegetation coverage. Maximum energy coefficient is about 0.5 in the hillslope system. The energy theory for output energy of runoff and soil erosion is presented by the energy coefficient theory associated with vegetation factor. Also runoff and erosion soil resulting output energy have the relation of power function and the rates of these increase with rainfall.