• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.358-364
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• 2007

This study was carried out to investigate the effect of phosphorus concentrations in fertilizer solution on growth and development of nutrient deficiency in leaf perilla (Perilla frutesens). The nutrient concentrations in above ground plant tissue, petiole sap and soil solution of root media were also determined. Phosphorus deficiency resulted in a slow growth, lustreless leaves, suffused purple tining in older leaves and falling prematurely. Elevation of P concentrations in fertilizer solution increased the crop growth at 75 days after transplanting. The fresh weight in 0, 0.5 and 4.0 mM treatments were 0.48 g, 9.28 g, and 25.5 g, respectively, and dry weights were 0.06 g, 1.46 g and 4.13 g, respectively. The P concentrations in above ground plant tissue and petiole sap in 4.0 mM treatment were 1.78% and $2.040mg{\cdot}kg^{-1}$, respectively, at 75 days after transplanting. The soil P concentration in 4.0 mM treatment was $1.26mg{\cdot}kg^{-1}$ when it was determined by the 1:2 (sample:water) method. These results indicated that P concentrations higher than 0.3% in above ground plant tissue, $900mg{\cdot}kg^{-1}$ in petiole sap, and $0.57mg{\cdot}kg^{-1}$ in soil solution should be maintained to ensure proper growth of leaf perilla (Perilla frutesens).

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.372-378
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• 2007

This study was carried out to investigate the effect of potassium concentrations in fertigation solution on growth and development of nutrient deficiency symptoms of leaf perilla (Perilla frutesens). The nutrient concentrations in above ground plant tissue, petiole sap and soil solution of root media were also determined. Potassium deficiency symptoms developed in older leaves with marginal necrosis. The brown areas on the lower leaves enlarged rapidly and the margins became scorched. Elevation of K concentrations in the fertigation solution up to 8 mM increased the crop growth in leaf length, stem thickness, and fresh and dry matter production of above ground plant tissue. However, that decreased the chlorophyll contents. The 8.0 mM K treatment which showed the greatest growth had 5.01 g in dry weight and 2.76% in K content of above ground plant tissue, suggesting that maintaining K content higher than 1.7% is necessary for good growth of Perilla frutesens. The K concentrations in petiole sap and soil solution of 8.0 mM treatment were $12,289mg{\cdot}kg^{-1}\;and\;11.65mg{\cdot}L^{-1}$, respectively. These indicated that K fertilization to maintain higher than $8,700mg{\cdot}kg^{-1}$ in petiole sap and $4.5mg{\cdot}L^{-1}$ in soil solution are necessary to ensure good crop growth.

• Journal of Environmental Impact Assessment
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• v.15 no.1
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• pp.1-12
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• 2006

Changes in the soil physical property and the topographic condition derived from agricultural activities like as farming activities, land clearance and cutting down resulted in environmental and economic problems including the outflow of nutrient from farms and the water pollution. Several theories on the soil conservation have been developed and reviewed to protect soil erosion in the regions having a high risk of erosion. This study was done using the USLE model developed by Wischmeier and Smith (1978), and model for the slope length and steepness made by Desmet and Govers (1996), and Nearing (1997) to evaluate the potential of the soil erodibility. Therefore, several results were obtained as follows. First, factors affecting the soil erosion based on the USLE could be extracted to examine the erosion potential in farms. Soil erodibility (K), slope length (L), and slope steepness (S) were used as main factors in the USLE in consideration of the soil, not by the land use or land cover. Second, the soil erodibility increased in paddy soils where it is low in soil content, and the very fine sandy loam exists. Analysis of the slope length showed that the value of a flat ground was 1, and the maximum value was 9.17 appearing on the steep mountain. Soil erodibility showed positive relationship to a slope. Third, the potential soil erodibility index (PSEI) showed that it is high in the PSEI of the areas of steep upland and orchard on the slope of mountainous region around Dokjigol mountain, Dunji mountain, and Deummit mountain. And the PSEI in the same land cover was different depending on the slope rather than on the physical properties in soil. Forth, the analysis of land suitability in soil erosion explained that study area had 3,672.35ha showing the suitable land, 390.88ha for the proper land, and 216.54ha for the unsuitable land. For unsuitable land, 8.71ha and 6.29ha were shown in fallow uplands and single cropping uplands, respectively.

• Journal of Environmental Impact Assessment
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• v.27 no.3
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• pp.279-290
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• 2018

The importance of monitoring and assessing the status of urban forests in the aspect of urban forest management is emerging as urban forest edges increase due to urbanization and human impacts. The purpose of this study was to investigate the status of vegetation condition of urban forest edge that is affected by different land cover types using $NDVI_{max}$ images derived from FSDAF (Flexible Spatio-temporal DAta Fusion). Among 4 land cover types,roads had the greatest effect on the forest edge, especially up to 30m, and it was found to affect up to 90m in Seoul urban forest. It was also found that $NDVI_{max}$ increased with distance away from the forest edge. The results of this study are expected to be useful for assessing the effects of land cover types and land cover change on forest edges in terms of urban forest monitoring and urban forest management.

• Journal of Korean Society of Forest Science
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• v.109 no.3
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• pp.291-299
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• 2020

The purpose of this study was to propose the most cost-effective sampling method, by analyzing the cost of forest resource investigation per sampling method for the planned harvesting area of in Chunyang-myeon, Byeonghwa-gun, Gyeongsangbuk-do, Korea. For this study, three sampling methods were selected: random sampling method, systematic sampling method, and line transect method. For each method, sample size, hourly wage, number of sample points, survey time, travel time, the sample error rate of the estimated average volume, and the desired sampling error rate were used to calculate the cost of forest resource inventories. Thus, 10 sampling points were extracted for each sampling method, and the factors required for cost analysis were calculated via a field survey. As a result, the field survey cost per ha using the random sampling method was found to be have the lowest cost, regardless of the desired sampling error rate, followed by the systematic sampling method, and the line transect method.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.420-430
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• 2005

As the pine wilt disease spread rapidly over Korea in recent, aerial pesticide spraying to the infected pine stands increased abruptly. The increasing aerial pesticide application for control of the disease would result in disturbance of soil ecosystem in pine stands. This study was conducted to assess the disturbance, using field experiment in pine stands of Hongleong experimental forests in Seoul with BACI experimental design with three sprayed plots and three unsprayed plots of $25m^2$. We sprayed fenitrothion of 0.0335 kg a.i./ha over each of the sprayed plots, being the same as the pesticide residues of litters after aerial spraying. The pesticide had been applied on 4 June, 11 June, and 29 June in 2002, comparable with the dates of the aerial spraying in the previous year in Busan. We monitored population of soil organisms including arthropods, fungi, bacteria, and actinomycetes at two sampling days before pesticide application, at two sampling days during the application season, and at three sampling days after last application for two months since late May in 2002. The pesticide applications did not make any significant effect on the population of arthropods, fungi, bacteria, and actinomycetes in soils and on the structure of soil organism community, showing low probability of significant effects of the aerial pesticide application on soil organisms in pine stands.

• Asian Journal of Turfgrass Science
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• v.12 no.1
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• pp.49-78
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• 1998

Nowadays, there are increasing demands of golf courses and it is necessary to make more golf courses than the present. To do this, we need to improve the environmental problems with the regional inhabitants, and it is said that the first thing to be considered in developing any golf course in Korea is to preserve the environment. In this context, the purpose of this study is to set forth several design factors to lessen the negative impacts which are accompanied with the development of golf courses. 1. The present conditions of golf courses in Korea Many new golf courses have come into being, particularly since the late 1980s, and now, in the year of 1997, over one hundred of golf courses are doing their business, yet the number of golf course is still less than required. So far, over a half of them have been made in the vicinity of Seoul on account of various reasons, and this has adversely affected on our natural environment. This unreasonable development of golf courses has caused serious water pollution, landslides and the other problems. Also, the topography of Korea is not good for golf courses. Although the demands of golf courses are increasing, the suitable sites for them are very limited, and therefore it is sometimes unavoidable to make golf courses on steep hills. Consequently, in designing golf courses in Korea, the most important thing is the balance between natural environment and artificial environment. 2.Eco-friendly golf course design factors 1) The concept of eco-friendly golf courses Ecologically sustainable and sound golf courses which are made by eco-friendly approaches 2)Basic conditions of eco-friendly golf courses (1)The most suitable sites (2) Conservation of existing ground as much as possible (3)Proper use of agricultural chemicals which have great impacts on the environment (4) Reasonable use of fertilizers (5) Developing a specialized fertilizer only for grass (6) Adaptation of organic agriculture (7) Improvement of grass sorts (8) Establishing reservoirs for purifying the water from golf courses 3) Eco-friendly golf courses (1) Location-Enough area /Gentle slope/Winding ground/Including lakes or streams /Not crossing wind's main direction Facing south or southeast /Suitable soIl for grass /Good drainage /Low level of underground water (2)Course layout and design -Consideration about existing contours as much as possible -Adaptation of Scotish design trend -Various holes' configuration -Consideration toward surrounding landscapes -Reducing grass areas -Giving buffer zones -Adapting computer methods in the process of site analysis and design (3) Eco-friendly considerations in constructing and managing golf courses -Protection of wildlife -Reuse of existing forests and preservation of topsoil -Renovation of old-fashioned courses -Reducing grass areas -Purification of water -Standization of management -Strict regulations against chemicals -Recycling organic materials -Through separation of the water inside golf courses and out of bounds -Getting proper construction works done in a due time 4.Eco-friendly considerations from a viewpoint of cultural environment 1) Well-matched landscape design and events planning 2) Implement of identifications and awarding systerns 3)Acknowledgement of superintendents' qualitications in the maintenance of golf courses 4)Increasing public golf courses and keeping good relationships with the neighbors near golf courses Key words: Pro-environmental development, Golf course.

• The Journal of Natural Sciences
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• v.14 no.2
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• pp.103-114
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• 2004

This study aims at investigating the effect of soil moisture control and truss limited high density culture on the growth, fruit yield and quality of tomato. To minimize of loss yield of tomato, flower cluster in number was limited to two and three truss and planting density was raised. Soil moisture control was started from 40 days after anthesis and irrigation point was set in -30kPa and -50kPa, which were compared with -10kPa For high density culture, the planting number of truss limited high density culture was planted twice as many as control. Soil moisture repression reduced the growth of stem diameter, leaf and plant height. Leaf chlorophyll content was higher in -50kPa and -30kPa than control. No significant differences, however, shows in -10kPa. The occurrence rate of bloom-end rot and cracking was increased by growing of irrigation repression. Pinching three fruit truss was higher than pinching two fruit truss in the occurrence rate of them. Soil moisture repression resulted in the reduction of fruit weight and in special, truss limited high density was distinctly decreased in -50kPa. The number of fruit was not affected by soil moisture control, but 3rd flower cluster was lower than 2nd flower cluster in the number of fruits and 2nd one was lower than 1st one. Under irrigation repression, rate of dry matter tended to grow in -30kPa, -50kPa compared with control and pinching three fruit truss was higher than two truss. Marketable yield dropped to 36.7%m 46.3 in -30kPa, -50kPa on pinching two fruit truss and dropped to 27.3%, 32.3% in 3rd flower cluster compared with control.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.625-633
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• 2016

This study was conducted to investigate the influence of hydrophilic polymer (HP) mixture ratio (Control, 1.0%, 2.5%, 5.0%, and 10.0%) on growth of eggplant (Solanum melongena) for lower maintenance urban agriculture via green roofs. Although it was not statistically significant (p > 0.05), substrate temperature was decreased as hydrophilic polymer mixture ratio were increased. High substrate water content (95%) was found consistently in growing media under elevated hydrophilic polymer mixture ratio at over 5% during the entire growing period. Substrate electronic conductivity was increased as hydrophilic polymer mixture ratio were increased. Growth index was decreased as hydrophilic polymer mixture ratio was increased. It was reduced about 1/3 and 1/5 compared to that of Control in HP5.0 and HP10.0 treatment plants, respectively. Number of leaves, leaf length, and leaf width were decreased in following order: Control> HP1.0> HP2.5> HP5.0> HP10.0 treatments. There numbers were significantly lower in HP5.0 and HP10.0 treatment plants. Dry weight of shoot and root were decreased as hydrophilic polymer mixture ratio was increased. They were reduced by 1/4 compared to those of Control treatment plants. In addition, visual value was decreased as hydrophilic polymer mixture ratio was increased. Plants grown in HP1.0, HP2.5, and HP5.0 treatments all survived. However, plants grown in the HP10.0 treatment had the lowest survival rate (56%) after 3 months of growing. These results indicate that the advantage of adding hydrophilic polymer to green roof growing media may greater during dry periods. However, the proper mixture proportion of hydrophilic polymer should be determined according to different characteristics of growing media and plant species.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.377-382
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• 2007

Porous mineral coating have been fabricated and applied for basic research on their slow release action to a fertilizer. Feldspar was selected as raw mineral for the coating and two different particle sizes of powder were prepared. Slow-release action was estimated by using a potassium sulfate fertilizer. Spherical pellets were prepared with a pan-type pelletizer and then screened into sizes ranging 1.4 to 2.35mm. While the fertilizer pellets were rotated in the pelletizer again, the feldspar powder and 0.5% polyvinyl alcohol solution were simultaneously sprayed on the pellets. The fertilizer pellets coated with feldspar powder were fabricated. The pellets were heated to increase their strength and screened to sort by coating thickness. Potassium releasing tests were conducted for 40 days and the performance for slow-release action was estimated as functions of the heating temperature, coating thickness and raw mineral powder size. The Burst effect caused high initial releasing rate. Releasing kinetics was proportional to concentration of potassium in pellets. The pellet that was fabricated with $27.4{\mu}m$-sized feldspar and heated at $1050^{\circ}C$ showed a releasing rate of 43% on the 40th day.