• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.189-195
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• 2019

In this study, we performed an analysis of the accumulation of inorganic arsenic and growth rate with changes in phosphate concentration in Hizikia fusiforme. When exposed to inorganic arsenic for fourteen days, we found that the collection of inorganic arsenic hardly increased at high phosphate concentrations (2 mg L^-1). However, when the phosphate concentration was low (0.02 mg L^-1), accumulation of inorganic arsenic increased. Additionally, H. fusiforme decreased in a growth rate of 14.5% in low phosphate concentration (0.02 mg L^-1) and fell in a growth rate of 30% when exposed to inorganic arsenic (10 ㎍ L^-1). H. fusiforme cannot distinguish between phosphate and inorganic arsenic. Thus, when phosphate concentration was lower, the inorganic arsenic accumulation increased, and accumulated inorganic arsenic inhibited photosynthesis and cell division, reducing the growth rate. H. fusiforme is known to have higher inorganic arsenic accumulation than other seaweeds. Therefore, various studies are needed to secure the food safety of H. fusiforme which is an essential aquaculture species in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.481-487
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• 1983

The need to synchronize flowering in two lines of different maturities is frequently encountered in hybrid com (Zea mays L.) seed production. To establish the methods for synchrony of flowering in parent lines of different maturities be effects of clipping at 4 and 6-leaf stages of growth and two levels, clear polyethylene mulching and five different planting dates on flowering date growth and seed yield of two dent com inbred lines of different maturities were evaluated Clipping just above the shoot-apex delayed pollen sheeding 6 to 9days and silking 5 to 13 days but reduced stand and seed yield 30 to 70% and 67 to 81%. respectively. Clipping 5cm above the shoot apex delayed flowering 1 to 4 days without stand reduction but reduced yield 3 to 29%. Laterclipping was slightly more effective for delaying flowering than earlier clipping but reduced stand more severely when clipped just above the shoot apex. Under clear polyethylene film mulching, flowering of two lines was 13 to 15 days earlier and seed yield of B68 (late line) was significantly increased. As planting was delayed from April 18 to June 13, the number of days from planting to flowering of two lines decreased due to increase in air temperature. However, growing degree days (GDD) from planting to flowering of each lines was similar regardless planting dates indicating that GDD can be satisfactoryly used for choosing the planting dates of parent lines of different maturities. Seed yields of two lines were decreased with delaying planting dates.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.50-55
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• 2013

The objective of this research was to investigate the impact of Ca fertilizer on the growth of mother plants, physiological disorders, and occurrence of daughter plants in propagation of 'Seolhyang' strawberry through plastic bag cultivation. To achieve this, chemicals of 1.125 mM $Ca(OH)_2$, 0.375 mM $MgCl_2$, 1.250 mM KCl were blended and designated to combined fertilizer (CF). Then, the effect was compared to the treatment of no Ca application (control) and a commercial fertilizer, CalMag (13-0-1.9-16-6:N-$P_2O_5$-$K_2O$-CaO-MgO), when those were applied every two weeks with controlled electrical conductivity (EC) of solution such as 0.6 or 1.0 $dS{\cdot}m^{-1}$. The number of plants showing Ca deficiency symptoms was the highest in control treatment, but those decreased significantly in CF or CalMag treatments. The differences between CF and CalMag in appearance of Ca deficient plants were not significant when two fertilizers were applied with same EC. The fresh and dry weights of mother plants were the greater in the treatments of CF or CalMag than those of control treatment. The treatments of 1.0 $dS{\cdot}m^{-1}$ of CF or CalMag were more effective than those of 0.6 $dS{\cdot}m^{-1}$ on the fresh and dry weight of the mother plants. The runner lengths in the treatment of 1.0 $dS{\cdot}m^{-1}$ of CF were the longest among the all treatments tested. The treatments of 1.0 $dS{\cdot}m^{-1}$ were more effective than those of 0.6 $dS{\cdot}m^{-1}$ of CF or CalMag in lengths and fresh and dry weight of runners. The fresh and dry weights of daughter plants were heavier in the treatments of CF than those of CalMag. Based on the above results, we concluded that the Ca deficiency in raising 'Seolhyang' strawberry can be lessened by the application of Ca containing fertilizers, but combined application of Ca, K and Mg was more effective than that of Ca alone for seedling production.

• Korean Journal of Environment and Ecology
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• v.36 no.3
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• pp.338-349
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• 2022

This study aims to investigate whether modular community planting, which entailed planting a variety of species of seedlings at high density, was more effective in restoring natural forests than the existing mature tree planting. We also investigated whether the planting density of the modular community planting facilitates growth or improves the tree layer coverage. We conducted outdoor experiments in which the samples were divided into a mature tree planting plot (control plot), where mature trees were planted at wide intervals, and a modular community planting (MCP) plot (treatment plot), where multiple seedlings were planted in high density. The MCP plot was further divided into the plot in which 3 seedlings were planted per m² and the plot of 1 seedling per m². We measured the specimens' survival rate, growth rate (tree height, crown width, and root collar diameter), and cover rate for 26 months from May 2019 and the predicted future tree height growth using the measured tree height. The survival rate and relative growth rate of the MCP were higher than those of the mature tree planting plot. The vertical coverage rate of the tree crown in the MCP exhibited complete coverage of the ground before 23 months, while the coverage rate of the mature tree planting decreased due to transplantation stress. The seedlings in the MCP, which were planted at high density, grew well and were predicted to grow higher than the mature trees in the large tree planting plot within 5 to 6.5 years after planting. It was due to multiple species, seedlings, high-density planting, and planting foundation improvements, such as soil enhancement and mulching. In other words, the seedlings planted in the MCP had a higher survival rate as their environmental adaptation after planting was better, and their early growth was also larger than the trees in the mature planting plot. The high-density mixed planting of various native species not only mitigated the inter-complementary environmental pressures but also facilitated growth by inducing competition between species. Moreover, the planting foundation improvement effectively increased the seedlings' viability and growth rate. A reduction in follow-up management costs is expected as the tree layer coverage sharply increases due to the higher planting density. In the MCP (3 seedlings per m² and 1 seedling per m²), the tree height growth was promoted with the higher planting density, and the crown width and root collar diameter tended to be larger with the lower planting density, but these differences were not statistically significant.

• Journal of agriculture & life science
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• v.44 no.5
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• pp.35-43
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• 2010

To examine the relationship between climate and tree-ring growth of Pinus densiflora S. et Z. growing in the ridges of the Baekdudaegan, it was analyzed the sample cores of 48 trees were collected from 21 sites. After the pattern of tree rings of all Pinus densiflora were cross-dating each other, it was recognized the growth of Pinus densiflora was affected by climate largely when tree-ring chronologies were standardized to remove the age-related growth. As a cluster analysis was conducted to examine the similarity of chronologies, three clusters were classified, the tree-ring growths of Pinus densiflora was not by regional or elevational gradients but by the growth tree-ring width amplitude as micro-site growth environments. Correlation coefficients between the chronologies of three clusters and monthly climate (temperature and precipitation) factors were obtained. As a result, tree-ring growth of Pinus densiflora was more affected by temperature than precipitation and the trees of high-growth cluster possessed less climatic influences.

• Journal of agriculture & life science
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• v.52 no.6
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• pp.37-47
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• 2018

The objective of this study was to analyze the influences of forest management activity on the diameter distribution of Larix kaempferi Carriere stands in South Korea. We used 232 managed stands data, 47 unmanaged stands data of National Forest Inventory for this study. We employed the Weibull distribution function for estimating diameter based on percentiles and parameter recovery method. The results revealed that the average diameter breast height movements and growth of tree in the managed stands higher than the unmanaged stands according to the scenario: age, site index, and tree density change. The finding shows the percentage of the total amount of large class diameter was also high in the managed stands. The results of this study could be apply for the estimation of multi-products of timbers per diameter classes and stand structure development for Larix kaempferi Carriere stands in South Korea.

• Journal of the Korean Institute of Landscape Architecture
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• v.16 no.1
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• pp.37-42
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• 1988

For the purpose of cultivating landscape plants, the culture soil of briquet ashes and sludge cakes from urban drainages was used as a bed soil. And Taxus cuspidata, syringa vulgaris, Ligstrum obtusifolia and Buxus microphylla were selected as experimental materials on this soil. The comparison of their growth showed the following results. Each plant showed a slight difference in primary growth and two months after planting, there were notable differences between treated and control plots respectively. Syringa vulgaris shoved the highest growth and the next were Ligstrum obtusifolia and Taxus cuspidata in series. Especially Taxus cuspidata showed the lowest quantity of dry weight compared with other plants, and influenced a little by mean temperature and solar radiation. It is expected to get a high effect in landscape planting by using briquet ashes and sludge cakes.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.101-101
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• 2021

본 연구에서는 금강 유역(9,645.5 km²)을 대상으로 SWAT(Soil and Water Assessment Tool)을 이용하여 장기간 지하수 양수와 산림 성장이 수문에 미치는 영향을 평가하였다. 1976년부터 2015년까지 40년의 지하수 이용량(GU)과 산림 성장(FG) 자료를 10년 단위(1980s; 1976~1985, 1990s; 1986~1995, 2000s; 1996~2005, 2010s; 2006~2015)로 구축하고, SWAT 입력자료와 증발산량 매개변수로 사용하여 연대별 지하수 양수와 산림 생장을 반영하였다. 금강 유역 내 위치한 2개의 다목적댐과 3개의 다기능 보에서 관측된 일별 유량으로 2006년부터 2015까지 10년을 검·보정하여 모델의 적용성을 검증하였다. 5지점에 대한 검보정 결과, NSE는 0.76에서 0.79, R²는 0.78에서 0.81, RMSE는 0.55 mm/day에서 1.96 mm/day, PBIAS는 -5.48%에서 8.56%로 통계적으로 유의한 수준으로 분석되었다. 적용성을 검증한 SWAT에 각 연대에 맞는 GU와 FG 정보를 입력하여 수문을 모의하였으며, 두 요인이 물순환에 미치는 영향을 평가하기 위하여 기상조건은 2010s로 고정하였다. 모의결과, GU와 FG 변화가 주는 영향으로 유역 출구의 총유출량은 7.8%(60.7 mm/year) 감소하였으며, 1980s과 2010s에서 각각 775.0 mm/year, 714.3 mm/year의 값을 보였다. 물순환 분석 결과, 지표유출, 중간유출, 기저유출, 침투량, 토양수분은 감소하는 경향을 보였고, 증발산량과 지하수 충전량(GWR)은 증가하는 경향을 보였다. GU의 증가로 인한 지하수위의 지속적인 감소가 GWR이 증가하는 원인으로 판단하였으며, 강우 기간에 포장용수량 이상의 토양수가 빠르게 흘러 지하수 충전량을 증가시켰다고 추론하였다. 또한, 유황 곡선을 분석한 결과, 유량이 지하수 양수와 산림 생장에 영향을 받은 지역에서 시간 흐름에 따라 감소하였고, 저유량 구간에서 상대적으로 많이 감소하였다.

• Journal of Mushroom
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• v.12 no.4
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• pp.371-374
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• 2014

Five to thirty percent of persimmon peels were added to mushroom medium to investigate mycelial growth. Mycelial growth on the medium with persimmon peels was 82~96 mm (28 days) and was slower than that of the control without persimmon peels as, 100 mm (28 days). Mycelial growth time on medium with 5 to 10% persimmon peels was similar to the control without persimmon peels as 28 days but that on medium with 30% persimmon peels was delayed for 4 days. The time of pinhead formations in medium with 10 to 20% persimmon peels was 8 days, the growth time to harvest was 10 days. These results were similar to those of the control without persimmon peels. The sizes of pileus of treatments with 10 to 30% persimmon peels were tend to be smaller compared with the control. The length of stipe of 10% persimmon peels treatment was 89 mm which was shorter than that of the control with 90 mm. The thickness of stipes of 10 to 20% persimmon peels treatments were 36 to 42 mm which were tend to be thicker than that of the control with 42 mm.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.331-335
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• 1996

1993년 전북완주와 충남 서산 지역에서 생강 근경 부패병에 감염된 식물체로부터 Pythium sp.를 분리하였으며, 52균주를 형태적 특징과 병원성 검정을 통해 Pythium zingiberum으로 동정하였다. P. zingiberum으로 동정된 균주들이 재배지에서 사용되는 metalaxyl(MT), metalaxyl+copper oxychloride(MC), echlomezol(EM) 및 propamocarb hydrochloride(PC)등에 균사 생장, 난포자 형성에 미치는 영향 및 약제방제 효과 등을 검토하였다. MT, MC, EM 등이 혼합된 평판배지에서의 균사생육 정도는 50, 100 mg/L에서도 균사생장 억제를 나타냈으나 3균주는 EM 100mg/L에서도 균사생장이 저지되지 않았다. 100mg/L에서도 균사생육 억제효과가 적은 PC의 경우 저항성균주의 난포자 형성량은 약제 희석농도가 높아질수록 저하되었으나, 감수성을 나타낸 균주는 10, 50mg/L에서 오히려 증가하였다. 또한 폿트실험을 통한 약효검정 결과에서도 MT, MC, EM등은 대조구에 비해 생강 근경부패병을 억제하였다.