• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.54-61
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• 1998

The subsurface environment of the root zone area can set the stae for "do or die" of the turfgrass plant. The good condition of the greens is verified by their physical properties. Therefore, this study was carried to evaluate on the existing green of Hwasan C.C. by undisturbed soil Core Anaysis. We completed the ISTRC SYSTEM BenchMarking of the undisturbed core samples taken from Green #1, Green #5, Green #9-"Best" area, and Green #9-"Stressed" area for the Hwasan C.C.. It was also our understanding that the greens were in "good" to "very good" conditioni. THe exception might be Green #9-"Stress" area, which was the stressed area. The stressed area was confined to a ridge across Green #9. The organic content test results comfirmed the development of organic layering in depth 0-2.5cm. For the amount of compaction in the upper root zones and te development of the green's respective organic layers, the infiltration rates were high in Green #1, Green #5, and Green #9 "Stressed" area. The depicted aerificaton hole might be the probable cause of the relatively high infiltraton rate. Green #9-"Best" area had a tested infiltration rate of 18.75cm/hr. Either this area had not been aerified, or the undisturbed sample did not contain a aerification cavity. The water retention capacity of the undisturbed samples was good. When the greens were first constructed, the original root zone mix had been relatively low water retention properties. And the bulk density and the porosity of the undisturbed samples were good. In the result, all the greens were similar except for the infiltration. Thus, we supposed that Green #9-"Stressed" area might be ainly influenced by the amount of irrigation water and the configuration of the green's surface. There had been a reduction in the amount of irrigation water as the water retention capacity in the greens was promoted. Especially, it had gradually become more of a problem as the green had matured in Green #9-"Stressed" area. Because Green #9-"Stressed" area was a ridge area. The reduction in the amount of irrigation water might be the probable cause of the stress in Green #9-"Stressed" area. Our final observation related to the soil texture and the particle size distribution of the sand. Though and sand contant of all the tested greens were good, the gravel content of them exceeded ISTRC Guidelines. In particle size distribution of the sand, the very coarse and the coarse content of all the tested greens exceeded, but the rest was insufficient. The stability is a function of the material retained on the 0.25mm mesh screen. But, the content of all the tested greens was very insufficient. Though all the greens was serviceable, the coarse root zone sands, such as the sand in the tested greens, tended to be "unstable". Thus, we recommend using a topdressing/aerification sand which should be more in line with ISTRC/USGA Guidelines.;unstable". Thus, we recommend using a topdressing/aerification sand which should be more in line with ISTRC/USGA Guidelines.ines.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.4
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• pp.253-259
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• 2013

The use of subsurface drip fertigation using slurry composting bio-filtration (SCB) as nitrogen (N) fertilizer source can be beneficial to improve fertilizer management decision. The objective of this study was to evaluate effects of SCB liquid fertilizer by subsurface drip fertigation on cucumber (Cucumis sativus L.) yield and soil nitrogen (N) distribution under greenhouse condition. Cucumber in greenhouse was transplanted on April $4^{th}$ and Aug $31^{st}$ in 2012. N sources were SCB and urea. Four N treatments with 3 replications consisted of control (No N fertilizer), SCB 0.5N + Urea 0.5N (50:50 split application), SCB 1.0N, Urea 1.0N. 100% of N recommendation rate from soil testing was denoted as 1.0N. The subsurface drip line and a tensiometer were installed at 30 cm soil depth. An irrigation was automatically started when the tensiometer reading was -15 kPa. The growth of cucumber at 85 days after transplanting was 5% higher in all N treatment than control. Semi-forcing culture produced more fruit yield than retarding culture. Fruit yields were 62.2, 76.3, 76.4, and 75.1 Mg $ha^{-1}$ for control, SCB 1.0N, Urea 1.0N, and SCB 0.5N + Urea 0.5N, respectively. Although fruit yields were similar under SCB 1.0N, Urea 1.0N, and SCB 0.5N + Urea 0.5N, 176 kg K $ha^{-1}$ can be over applied if cucumber is grown twice a year under SCB 1.0N that may result in K accumulation in soil. N uptake was 172, 209, 213, 207 kg $ha^{-1}$ for control, SCB 1.0N, Urea 1.0N, and SCB 0.5N + Urea 0.5N, respectively. N use efficiency was the highest (37%) at SCB 0.5N + Urea 0.5N under semi-forcing culture. Nitrate-N concentration in soil for all N treatments except control in semi-forcing culture was the highest between 15 and 30 cm soil depth at the 85 days after transplanting and between 0 and 15 cm soil depth after cucumber harvest. These results suggested that SCB 0.5N + Urea 0.5N can be used as an alternative N management for cucumber production in greenhouse if K accumulation is concerned.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.3
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• pp.201-207
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• 2007

To reduce both the floatation of the seedling of rice and the failure in standing in the paddy field when the barley straw was applied to paddy field before planting the rice, we tested the effect of rice rooting with plowing methods and irrigation rates for 2 years from 2003 to 2004. This study was carried out in paddy field with Fluvio-Marine deposit in Jeonbug series and the operating accuracy and the change of soil physico-chemical properties depending on plowing methods and irrigation rates following the barley straw applying were examined. There was a less floatation of barley straw in the dry-rotaryI+water-rotaryI(DRI+WRI) plot than in the plowing+water-rotary(PL+WRI) plot. The ratio of miss-planted and floating seedling also decreased by 1.7%, 2.6% in the DRI+WRIplot compared with PL+WRI plot. The soil physical property was improved with the decreasing soil hardness, bulk density and increasing soil porosity after the application of barley straw, especially enhanced greatly in the increase of porosity, gaseous phase and with the decrease of soil hardness, bulk density of subsurface soil in DRI+WRI plot. And the change of soil chemical property were increased the content of total carbon$^{\circ}{\S}$nitrogen$^{\circ}{\S}$organic matter and available phosphate while decreased the content of exchangeable cations and available silicate after the application of barley straw. Also the content of organic matter, available phosphate and cation exchangeable capacity were increased, whereas caron/nitrogen ratio was decreased in DRI+WRI plot compared with PL+WRI plot. The number of panicles, spikelets per square meter were increased and 1,000 grains weight of hulled rice was gained more in DRI+WRI plot at irrigation rate of $500ton\;ha^{-1}$, in DRI+WRII plot at irrigation rate of $700ton\;ha^{-1}$. So the rice yields were increased by 7%, in DRI+WRI and 5% in DRI+WRII plot, respectively compared with PL+WRI plot. The result of this study indicated that the most appropriate plowing method with barley straw application on rice cultivation at double cropping in normal paddy field plain land was DRI+WRI.

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.2
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• pp.2262-2275
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• 1971

Fourteenes rervoirs maintained by the local land improvement associations in the province of Chullabuk-Do and 20 reservoir maintained by thos in the province of Chullanam-Do, were surveyed in connection with a correction between storage capacity and sediment deposit. In addition to this survey, 3,347 of small reservoir, that lie scattered around in the above-mentioned two provinces were investigated by using existing two provinces were investigated by using existing records pertaining to storage capacity in the office of City and country, respectively. According to this investigation the following comclusions are derived. 1. A sediment deposition rate is high, being about $10.63m^3/ha$ of drainage area, and resulting in the average decreasc of storage capaity by 27.5%. This high rate of deposition coule be mainly attributed to the serve denudation of forests due to disorderly cuttings of trees. Easpecially, in small reservoir, an original average design storage depth of 197mm in irrigation water depth is decreased to about 140mm. 2. An average unit storage depth of 325.6mm as the time of initial construction is decreased to 226mm at present. This phenomena causes a greater shortage irrigation water, since it was assumed that original storage quantity was already in short. 3. Generally speaking, seepage rates through dam abutment intakepipe, etc, are high due to insufficient maintenance and management of reservoir. 4. It is recommended that sediment deposit should be dredged when a reservoir is dry in drought. 5. Farmers usually waste excessive irrigation water. 6. Water saving methods should be practiced by applying only necessary water for growing stage of rice. 7. In are as where water defficiency for irrigation is severe, a soil moisture content should be kept at about 70% by applying water once in several days. 8. Tube wells should be provided so as to exploit ground water and subsurface current below stream bed as much as possible. 9. If an intake weir was constructed, a water collection well should be built for the use in drought. 10. Water conservation should be forced by converting devastated forests contained in the drainage area of reservoir to protected forests so as to take priority of yrefor estation, gully control, the prohibition of disorderly cutting of trees, etc. 11. Collective rice nurseries should be adopted, and it should be recommended that irrigation water for rice nurseries is supplied by farmer themselves. 12. Sediment desposit in reservoir should be thoroughly dreged so as to secure a original design storage capacity. 13. The structure of overflow weir should be automatic so as to freely control flood level and not to increase dam height.

• The Journal of Engineering Geology
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• v.5 no.3
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• pp.289-300
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• 1995

At the initial stage of the underground reservoir design one should thoroughly consider surface and subsurface hydrology, hydrogeologic characteristics of aquifer system, and the function of cut - off wall because it is linked to the effective management. In this study, three dimensional finite difference model was applied to analyse the function of Ian underground reservoir at Kyungbuk Province. The steady and unsteady state conditions after construction of the underground dam were simulated through the model, and from these results the groundwater budget and the safe yield were determined. The model simulation indicates the infiltration of irrigation water to be one of the major factors of seasonal fluctuation of groundwater level. The recharge rates of irrigation water were estimated as 4.3mm/d during May and June, and 1.7mm/d during July and Agust. Groundwater recharge from the watershed area estimated to about $0.04m^3/s$, almost consistent through the year. In 1984, groundwater discharge through the transverse section of the dam was $0.002m^3/s$ and the optimum yield for two momths(July and Aguest)was $254000m^3$, however, the discharge became $0.013m^3/s$ in1993, implying the failure of cut -off function. without appropaiate of the cut - off wall, optiumum yield during the irrigaton period would be $93, 000m^3$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.385-397
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• 1982

The climatic impacts have been the environmental constraints with soil characteristics to achieve self sufficiency of food production in Korea. In this paper, the distribution and appearance of impacts and the changes in climatological status due to recent trend of early transplanting of rice are widely discussed to derive some countermeasures against the impacts, being focussed on cultural A long term analysis of the climatic impact appearances of the last 74 years showed that drought, strong wind, flood, cold spell and frost were the major impacts. Before 1970's, the drought damage was the greatest among the climatic impacts; however, the expansion and improvement of irrigation and drainage system markedly decreased the damage of drought and heavy rain. The appearance of cold damage became more frequent than before due to introduction of early transplanting for more thermophilic new varieties. Tongillines which were from Indica and Japonica crosses throw more attention to cold damage for high yields to secure high temperature in heading and ripening stages and lead weakness to cold and drought damage in early growth stage after transplanting. The plants became subject to heavy rain in ripening stage also. For the countermeasures against cold damage, the rational distribution of adequate varieties according to the regional climatic conditions and planting schedule should be imposed on the cultivation. A detoured water way to increase water temperature might be suggestable in the early growth stage. Heavy application of phosphate to boost rooting and tillering also would be a nutritional control method. In the heading and ripening stages, foliar application of phosphate and additional fertilization of silicate might be considerable way of nutritional control. Since the amount of solar radiation and air temperature in dry years were high, healthy plants for high yield could be obtained; therefere, the expansion of irrigation system and development of subsurface water should be performed as one of the national development projects. To minimize the damage of strong wind and rainfall, the rational distribution of varieties with different growing periods in the area where the damage occurred habitualy should be considered with installation of wind breaks. Not only vertical windbreaks but also a horizontal wind break using a net might be a possible way to decrease the white heads in rice field by dry wind. Finally, to establish the integrated countermeasures against the climatic impacts, the detailed interpretation on the regional climatic conditions should be conducted to understand distribution and frequency of the impacts. The expansion of observation net work for agricultural meteorology and development of analysis techniques for meteorological data must be conducted in future together with the development of the new cultural techniques.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.93-115
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• 2009

There are growing public concerns over crop and food safeties due to the elevated levels of heavy metals grown in contaminated soil. Heavy metals are classified as the chemical harmful risks for crop and food safety. With implementation of GAP, crop safety is controlled by many regulatory options for soil, irrigation water and fertilizers. Any attempt to retard the metal uptake by crops may be the best protocol to secure crop and food safety. This article reviews the management strategies for heavy metals in view of crop safety in Korea and demonstrates results from the field experiments to retard metal translocation from soil to crops by using chemical amendments and soil layer management methods. Major source of soil pollution by heavy metals has been related with mining activities. Risk assessment revealed that rice consumption and groundwater ingestion in the abandoned mining areas were the major exposure pathways for metals to human and the heavy metal showed the toxic effects on human health. Chemical amendments such as lime and slag retarded Cd uptake by rice (Oryza sativa L.) by increasing soil pH, lowering the phytoavailable Cd concentration in soil solution, immobilizing Cd in soil and converting the available Cd fractions into non-available fractions. The soil layer management methods decreased the Cd uptake by 76% and Pb by 60%. Either reversing the surface layer with subsurface layer or immobilization of metals with layer mixing with lime was considered to be the practical option for the in-situ remediation of the contaminated paddy soils. Combination of chemical soil amendments and layer management methods was efficient to retard the metal bioavailability and thus to secure crop safety for heavy metals. This protocol seems to be cheap, relatively easy to practice and practical in the agricultural fields. However, a long term monitoring work should be followed to verify the efficiency of this protocol.

• KCID journal
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• v.19 no.1
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• pp.40-49
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• 2012

This study was performed to monitor the runoff of sandy soils on alpine uplands between March 2008 and December 2009, and assess non-point source pollution load. The fields were used to cultivete poteto in 2008 and radish in 2009. The fertilizers used in 200S, compared to those used in 2009, contained 2.1 times of nitrogen, 1.9 times of phosphorous, and 2.3 times of potassium. In 2008, the annual pollution load indiceted SS 2,908.47kg/ha/yr, COD 67.95kg/ha/yr, BOD 50.72kg/ha/yr, TN l3.29kg/ha/yr, and TP 9.97kg/ha/yr. In 2009, the annual pollution load indiceted SS 3,908.34kg/ha/yr, COD 225.04kg/ha/yr, BOD 156.96kg/ha/yr, TN 18.88kg/ha/yr, and TP 36.41kg/ha/yr. The amount of fertilizers used was about twice greeter in 2008, but the amounts of TN in pollution load per unit of rainfall were similar by 0.031kg/ha/mm to 0.029kg/ha/mm, whereas the amounts of COD (0.16kg/ha/mm to 0.35kg/ha/mm), BOD (0.12kg/ha/mm to 0.24kg/ha/mm), and TP (0.023kg/ha/mm to 0.057kg/ha/mm) doubled in 2009. We can infer thet the surface covering by the growth of crop mainly affected the transport of T-N through the subsurface flow to reduce non-point source pollution.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.353-360
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• 2009

Phosphorus (P) is one of the essential elements of the phospholipids that are involved in the formation of plant cell membranes. Phosphorus is highly immobile in soils and is often a limiting nutrient for plant growth. Phosphorus mobility and availability varies with several factors such as application frequency, placement in the soil, and the amount of irrigation or precipitation. This study was conducted to evaluate the effect of P applications at level of 0, 146, and 293 $kg{\cdot}ha^{-1}$ at four mixing depths (0, 7.6, 15.2, and 22.9 cm )on the growth and establishment of Kentucky bluegrass (Poapratensis L.) in a sand-based system.Grass clipping samples were collectedevery two weeks, dried, and weighed. Total root dry weight, root organic matter, and tissue content of P were measured at the end of the study. Leachate was collected weekly and analyzed for total P concentration. No difference was found between application of P to the surface and to the 7.6 cm mixing depth. However, surface application with 146 and 293 kg $P{\cdot}ha^{-1}$ produced 8-10% and 16-20% more P in tissue than subsurface applications, respectively.

• Journal of Wetlands Research
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• v.23 no.3
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• pp.242-251
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• 2021

Surface water pollution is a serious environmental problem in developing countries, like India, due to the unregulated discharge of untreated wastewater. To overcome this, the constructed wetlands (CWs) have been proven to be an efficient technology for wastewater treatment. In this study, different existing and experimental facilities were reviewed to be able to determine the current status of constructed wetlands in India. Based on the collected data from published literature, industrial wastewater contained the highest average chemical oxygen demand (COD), biochemical oxygen demand (BOD). In terms of total nitrogen (TN), Total phosphorous (TP), the lowest concentration was found on domestic wastewater. Vertical flow constructed wetlands (VFCW) and Horizontal flow constructed wetland (HFCW) were more effective in removing TSS, BOD, TP in domestic and industrial wastewater, whereas hybrid constructed wetlands (HCW) showed the highest removal for COD. The use of constructed wetlands as advanced wastewater treatment facilities in India yielded better water quality. The treatment of wastewater using constructed wetlands also enabled further reuse of wastewater for irrigation and other agricultural purposes. Overall, this study can be beneficial in evaluating and promoting the use of constructed wetlands in India.