• Title/Summary/Keyword: per unit area

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The Calculation of NPS Load per Unit Area in Orchard to the Nakdong River Basin (낙동강유역 과수재배지의 단위면적당 비점오염부하량 산정에 관한 연구)

  • Lee, Jae-Woon;Kwon, Heon-Gak;Yi, Youn-Jeong;Cheon, Se-Uk
    • Journal of Environmental Impact Assessment
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    • v.22 no.6
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    • pp.557-568
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    • 2013
  • In this study, Calculated the nonpoint sources(NPS) load per unit area about various rainy events in vineyard of Nakdong River basin. NPS monitoring and calculation for NPS load per unit area were estimated from 'Investigation method of precipitation discharge(National Institute of Environmental Research, 2007)'. The evaluation of applicability for NPS load per unit by compared with prior research data and Total Maximum Daily Load(TMDL) data. Five target areas were each $2000m^2$, $1800m^2$, $1943m^2$, $2484m^2$, $864m^2$ and located in Gyeongsangbukdo Gyeongju, Gyeongsangbukdo Sangju, Gyeongsangnamdo Hapcheon in Korea. Since fruits were the only crop on the target area, the characteristics of stormwater discharge at survey sites could be evaluated independently. A total of 115 rainfall events in the Orchard area during five years(2008-2012) was surveyed, and 38 of them became stormwater discharge. In the Nakdong River watershed, average of event mean concentrations(EMCs) in Orchard area for biochemical oxyzen demand(BOD), Chemical oxyzen demand(COD), total nitrogen(T-N), total phosphorus(T-P) were 2.0mg/L, 10.1mg/L, 3.195mg/L, 0.578mg/L, respectively. NPS load per unit area in Orchard area showed BOD : $2.0kg/km^2{\cdot}day$, COD : $10.2kg/km^2{\cdot}day$, T-N : $3.220kg/km^2{\cdot}day$, T-P : $0.606kg/km^2{\cdot}day$.

Comparative Leaf Characteristics of Quercus Mongolica and Rhododendron Schilippenbachii Plants Inhabiting at South- and North- Facing Slopes around Mountain Ridge

  • Park, Yong Mok
    • Journal of Environmental Science International
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    • v.22 no.10
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    • pp.1345-1351
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    • 2013
  • Leaf characteristics of two representative deciduous-tree species in Korean peninsula were compared to assess directional ridge effect on leaf traits of both species. Leaf mass per unit area (LMA) of Rhododendron schilippenbachii in south-facing ridge slope was significantly higher than that in north-facing ridge slope, while Quercus mongolica did not change LMA. Leaf mass of Q. mongolica was increased depending on leaf size irrespective of slope. However, leaf mass of R. schilippenbachii changed differently in responding to expansion of leaf area between both slopes resulting from retardation of leaf expansion in south-facing slope. R. schilippenbachii showed higher leaf nitrogen concentration per unit area (LNCA) in south-facing slope than that in north-facing slope, while Q. mongolica indicated no difference in LNCA between southand north-facing slopes. However, both species revealed no significant difference in leaf nitrogen concentration per unit mass (LNCM) between south- and north-facing slopes. LNCA of Q. mongolica was about two times higher than that of R. schilippenbachii. These results indicate that there is a difference in leaf characteristics including leaf thickness and nitrogen allocation between Q. mongolica and R. schilippenbachii, suggesting the difference of plasticity.

Study on the Salt Tolerance of Rice and Other Crops in Reclaimed Soil Areas 3. Response of Rice to Plant Population and Spacing in the Slty Soil Area (3. 간척지에서 수도개체군과 재식밀도에 관하여)

  • 임형빈
    • Journal of Plant Biology
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    • v.12 no.2
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    • pp.28-42
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    • 1969
  • Field studies were conducted with the split plot design of 20 treatment with a combination of 4 levels of 3, 5, 7 and 9 plants per hill and 5 levels of 60, 80, 100, 120 and 140 hills per 3.3$m^2$ on non-, low- and high-salty areas. Rice variety, Kusabue was grown under jthe standard fertilization and cultivating. Investigation was made on the productive structure of plant population, leaf-area index, light intensity curve by stratum of crop population at the panicle differentiation stage. The competition density effect on the photosynthetic capacity was low as the salt concentration became higher. This seemed to suggest the possiblity of an increased yielding capacity by closer planting in the salty areas. The effect of an increased number of hills per unit area was greater than that of an increased unmber of plants per hill due to the total leaf area and space distribution of the actie assimilation parts of rice plants. The number of ppanicle per unit area in the salty areas were increased when the number of hill per 3.3$m^2$ increased over an increased number of plants per hill, and the panicle weight was reduced by close planting in the non-lalty area, while it was not reduced so much in the salty areas. The number of grains per panicle was significantly decreased by close planting in the salty areas as in the non-salty area, and ratio of matured grain was not decreased even by close planting in the salty areas, while it was significantly decreased by close planting in the non-salty area. An increase in the rice yield was possible by close planting and greatly related to leaf area index in the salty areas but not in the non-salty area. Increasing the number of hills per unit area showed greater effect on the increase of the rice yield than an increased number of plants per hill in the salty areas. Relationships between the growth characteristics and the rice population affected by plant spacing mode for maximum production were discussed.

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Effects of Deep Seawater on the Growth of a Green Alga, Ulva sp.(Ulvophyceae, Chlorophyta)

  • Matsuyama, Kazuyo;Serisawa, Yukihiko;Nakashima, Toshimitsu
    • ALGAE
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    • v.18 no.2
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    • pp.129-134
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    • 2003
  • In order to examine the effects of deep seawater (mesopelagic water in the broad sense) on the growth of macroalgae, the growth and nutrient uptake (nitrate and phosphate) of Ulva sp. (Ulvophyceae, Chlorophyta) were investigated by cultivation in deep seawater (taken from 687 m depth at Yaizu, central Japan, in August 2001), surface seawater (taken from 24 m depth), and a combination of the two. Culture experiments were carried out in a continuous water supply system and an intermittent water supply system, in which aerated 500-mL flasks with 4 discs of Ulva sp. (cut sections of ca. 2 $cm_2$) were cultured at 20$^{\circ}C$ water temperature, 100 $\mu$mol photons $m^{-2}{\cdot}s^{-1}$ light intensity, and a 14:10 light:dark cycle. Nutrient uptake by Ulva sp. was high in all seawater media in both culture systems. The frond area, dry weight, chlorophyll a content, dry weight per unit area, and chlorophyll a content per unit area of Ulva sp. at the end of the experimental period were the highest in deep seawater and the lowest in surface seawater in both culture systems. These values, except for dry weight per unit area and chlorophyll a content per unit area, for each seawater media in the intermittent water supply system were higher than those in the continuous water supply system. We conclude that not only deep seawater as the culture medium but also the seawater supply system is important for effective cultivation of macroalgae.

Assessment of agricultural Organic Matter Flow in a Rural Area (농촌지역에서의 농업 유기물 흐름의 평가)

  • 김진수
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.5
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    • pp.114-124
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    • 2000
  • The method to estimate agricultural organic matter flow on the regional scale was established and applied to a rural area in Chongwon-gun, Chungbok in 1996. The study area is of about 67$\textrm{km}^2$ and its population is about 7,000. The stocks and flows of organic matter are represented in dry weight per unit area and dry weight per unit area per year, respectively. the amount of inflow of organic matter indicates a possibility to cause environmental pollution. the amount of animal waste 767 kg/ha/yr account for 42 percent of total amount of organic waste 1,834 kg/ha/yr and therefore the environment in study area is greatly influenced by livestock. The decrease in recycling rate of animal waste form 100% to 70% has greatly increased the amount of disposal waste nearly twice, i.e., from 267 kg/ha/yr to 497kg/ha/yr . The results of this study demonstrate that appropriate animal population, increase in recycling of animal waste and preservation of agricultural land are necessary for environmental conservation of the study area.

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A Study on the Change of the Apartment Unit Plan in National Housing - Focused on Institutional and Social Changes - (국민주택(전용 85 m2 이하) 아파트평면의 변화에 대한 연구 - 제도적 변화와 사회적 변화를 중심으로 -)

  • Choi, Kwon-Jong;Jihn, Jung
    • Journal of the Korean housing association
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    • v.26 no.5
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    • pp.123-131
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    • 2015
  • The purpose of this study is to suggest an optimum guide line of the unit plan design in national housing (less than $85m^2$ of exclusive floor area in a dwelling unit). The unit plan of apartment have been improved diversely for the residents, and the family members per household have been decreased for decades comparing with the past. In contrast, the living space per household has been increased steadily, it is because of the improvement of the living standard. The unit plan have been improved from 2-bay corridor access type and 2~3 and 4-bay staircase type. In december 2005, the balcony was permitted to be used as exclusive living area without the increase of the original living area by law. So the apartment residents have been able to use more spacious area exclusively in a dwelling unit. On the other hand, the legalization on permitting balcony area into a exclusive area resulted in a distorted wide and enlarged plan only for the business profit improvement lately. The living environment has been changed differently unlike at the time of the legislation of the national housing. The family member per household has been decreased and the related law and the institution has also been changed. Moreover It has passed 40 years since the legislation of national housing ($85m^2$). So, The size of national housing should be reviewed according to the current trend in terms of the decrease of household and the utilization of balcony area.

재식밀도와 질소시용이 오차드그라스 ( Dactylis glomerata L. ) 품종들의 분벽 소장과 수량에 미치는 영향 ( The Effect of Plant Density and Nitrogen Application on the Tillerring and the yield in cultivars of Orchargrass ( Dactylis glomerata L. ) )

  • 김정해;이호진
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.10 no.1
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    • pp.1-9
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    • 1990
  • Tillering of orchardgrass during establishment year was considered as an important factor for ground cover and forage yield. Field experiment was conducted to examine seasonal fluctuation of tiller number in three cultivars of orchardgrass; Potomac, Hall-mark, and Sumas, after transplanting with five planting density. Also, effects of plant density and nitrogen application in cultivar, Potomac were studied on tillering, forage yield and various growth characteristics in pot experiment Tillers per plant decreased with increased density and showed seasonal variations. It increased up to July, decreased during summer months, and increased again from October. Sumas had less tillers than other cultivars, especially at high density. Tillers per unit area kept high during spring. After then, there was stady decrease through summer and remained constant without affecting by planting density. Nitrogen application increased tillers per unit area in Potomac up to 20kg/10a, but decreased its tiller production at 40kg/lOa. Maximum number of tiller was obtained in the combinations of 20kg application of nitrogen with higher density than 324 plant per square meter. Forage yield increased as nitrogen application increased, while it did not respond to plant density. Forage yield had high linear correlation between LAI, leaf number with a peak at 2800 culrns. For high forage yielding, it was suggested to obtain optimum number of tillers per unit area in early season as possible, applying of adequate amount of nitrogen with relative high density depend on cultural condition.

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Effects of Growth Characteristics on the Yield, Quality, Chemical Contents and Physical Properties in some Burley Tobacco Varieties (버어리종 담배 품종의 생육특성이 수량, 품종, 내용성분 및 물리성에 미치는 영향)

  • 김상범;백기현;한철수;추홍구
    • Journal of the Korean Society of Tobacco Science
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    • v.4 no.2
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    • pp.41-50
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    • 1982
  • To investigate tile effects of growth characteristics on the yield, price per Kg, chemical contents and physical properties in Burley tobacco, ten varieties including Burley 21 were tested in this study. The results obtained are summarized as follows. 1 Forty to fifty days after transplanting, CCR (Crop Growth Rate) was the highest. RCR (Relative Growth Rate) increased up to 40 days, but decreased 50 days when maturation began. High- yielding varieties showed high CCR and RCR till 60 days. 2. Total alkaloid content of cured leaf increased about three times than that of topping stage, but the increased rates were some what different among varieties. 3. Leaf area, stalk diameter, stalk height and days to flower showed positive correlations to yield, whereas leaf thickness and weight per unit leaf area showed negative. 4 Varieties which are high in cured leaf weight ratio and weight per unit leaf thickeners showed relatively poor quality. 5 Nitrogen content was high in leafy and larger stalk diameter variety. 6. There are positive correlation between weight per unit leaf thickness and filling power. The time of combustion was positively correlated to leaf thickness and weight Per unit leaf. 7. It can be concluded that many characteristics are related to the yield, but not quality. It is, there fore, easy to Predict tile yield, but difficult to forecast the qualiffy.

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Improvement of Cooperation Charge on Conservation of Ecosystem Reflected Natural Capitals Valuation - Focused on Forest Area - (자연자산의 가치를 반영한 생태계보전협력금 제도 개선 방안 - 산림지역을 중심으로 -)

  • Park, Jin-Han;Lee, Dong-Kun;Tanaka, Riwako;Kim, Jung-Taek;Jeon, Seong-Woo;Lee, Woo-Kyun;Kim, Joon-Soon;Jung, Tae-Yong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.1
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    • pp.203-213
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    • 2014
  • In Korea, a cooperation charge on conservation of ecosystem is imposed to prevent indiscriminate development. The total amount of this charge is determined by multiplying the size of the destroyed area by a value per unit area and the area index within 5 billion won. Since 2001, the charge per unit area has been determined to be $250won/m^2$. In this study, we estimated the unit value of ecosystem services per year using benefit transfer method, with a focus on forest resources. According to our results, forest resources have a value of about $3,500won/m^2$ per year. When the non-use value is subtracted, that figure becomes approximately $1,300won/m^2$. If this value incorporates the unit value of the cooperation charge on conservation of ecosystem, it will increase. To comply with the original intent of the cooperation charge on conservation of ecosystem, the fund must be used to improve ecosystem services, including the restoration of a destroyed area or the purchase of new land.

Understanding the seasonal status of fisheries resource in the East China Sea by using bottom trawl (저층트롤을 이용한 동중국해 해역의 계절별 수산자원 현황)

  • Hyoung-Ho SHIN;Jungkwan LEE;Geunchang PARK;Byeong Gwon LIM;Doo Jin HWANG;Kyounghoon LEE
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.3
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    • pp.231-241
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    • 2023
  • This study was investigated in order to find composition and density of fisheries resource using bottom trawl in April, July, August, and November 2022 in the East China Sea. The average density of fisheries resource was estimated using the swept area method. As a result, 35 species were collected from the East China Sea. These included 21 fishes, six crustaceans, six cephalopods and two echinoderms. Seasonally, the average density of crustacean individuals per unit area were highest in November (692.1 inds./km2), while cephalopod individuals per unit area were highest in August (39.4 inds./km2). The average density of fish individuals per unit area were highest in August at 355.0 (inds./km2).