• Journal of Forest and Environmental Science
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• 제36권1호
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• pp.37-46
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• 2020

Vegetation carbon sequestration and regeneration are the two major parameters of forest research. In this study, we analyzed the vegetation carbon stock and regeneration of community-managed pine plantation of Kathmandu, central Nepal. Vegetation data were collected from 40 circular plots of 10 m radius (for the tree) and 1m radius (for seedling) applying a stratified random sampling and nested quadrat method. The carbon stock was estimated by Chave allometric model and estimated carbon stock was converted into CO₂ equivalents. Density-diameter (d-d) curve was also prepared to check the regeneration status and stability of the plantation. A d-d curve indicates the good regeneration status of the forest with a stable population in each size class. Diversity of trees was very low, only two tree species Pinus roxburghii and Eucalyptus citriodora occurred in the sample plots. Pine was the dominant tree in terms of density, basal area, biomass, carbon stock and CO₂ stock than the eucalyptus. The basal area, carbon stock and CO₂ stock of forest was 33±1.0 ㎡ ha^-1, 108±5.0 Mg ha^-1 and 394±18 Mg ha^-1, respectively. Seedling and tree density of the plantation was 4,965 ha^-1 and 339 ha^-1 respectively. The forest carbon stock showed a positive relationship with biomass, tree diameter, height and basal area but no relationship with tree density. Canopy cover and tree diameter have a negative effect on seedling density and regeneration. In conclusion, the community forest has a stable population in each size class, sequestering a significant amount of carbon and CO₂ emitted from densely populated Kathmandu metro city as the forest biomass hence have a potentiality to mitigate the global climate change.

• 펄프종이기술
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• 제46권5호
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• pp.9-18
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• 2014

London Convention on the prevention of marine pollution by dumping of wastes and other matter prohibits the deliberate disposal of paper mill sludges at sea. In order to explore the alternative plan on the prohibition of sludge disposal at sea, the biodegradable seedling pot was developed by mixing the sludge with old newspaper (ONP) in appropriate mixing ratios. The C/N ratio of the mixed sludge was below 20, leading to rapid deterioration of the organic matters composing the seedling pot. The increased ONP contents in the seedling pot resulted in the increase of pot thickness and thereafter in the decrease of pot density. Cellulose fibers in ONP promoted water absorption of the pot but AKD addition helped the seedling pot to repel water during raising seedling. Breaking length and burst strength of the seedling pot were improved by addition of wet strength additives but air permeability was a little diminished. Biodegradable rate of the seedling pot in a soil was accelerated by the attack of soil microbes at the beginning, and finally the pot was completely degraded in 150 days in a soil.

• Current Research on Agriculture and Life Sciences
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• 제19권
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• pp.1-8
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• 2001

벼 자동화 육묘시설에서 상토의 종류와 파종량이 묘생육에 미치는 영향을 조사분석한 결과를 요약하면 다음과 같다. 상토의 성분분석 결과 산도(pH)는 '삼경상토'가 8.6으로 가장 높았고 '부농 2호'는 5.1로 가장 낮았다. 유효인산 함량은 '부농 1호'가 843 ppm으로 가장 높았고 '자가상토'에서 74 ppm으로 가장 낮았다. 전질소함량은 '원조상토' 및 '부농 1호', '부농 2호', '부농 3호'에서 다른 상토에 비해 높은 경향을 나타내었다. 상자당 파종량이 250 g 일때 상토의 종류에 따른 15일묘의 초장은 '부농 1호', '부농 2호', '부농 3호'에서 14.2~14.9 cm로 나타난 반면, '자가상토'에서의 초장은 13.1 cm로 짧았다. 상자당 파종량이 300 g으로 증가하면 상토 종류에 관계없이 묘초장은 길어졌고 그 차는 10일묘에서 보다 15일묘에서 크게 나타났다. 상토의 종류에 따른 15일묘의 건물중은 '부농 2호'가 13.3 mg으로 가장 무거웠고, 묘충실도도 '부농 2호'에서 0.96으로 가장 높았으며 '자가상토'와 '자가상토'에 시판상토(부농 2호)를 혼용한 처리구에서의 묘생육은 본 시험에 공시된 6종류의 시판 상토에 비해 저조하였고，매트형성도 불량하였다.

• Journal of Ginseng Research
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• 제8권1호
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• pp.65-74
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• 1984

This experiment was carried out to study the effects of light intensity and soil water regimes on the growth of ginseng seedling. The results were as follows: 1. The maximum light intensity and optimum temperature in 1,le photosynthesis of ginseng seedling were 10,000 lux and 23 $^{\circ}C$. Respiration rate was increased at high temperature. 2. Air and soil temperature under the shading were increased as the increase of light intensity but soil water contents were decreased as the increase of light intensity, whereas air and soil temperature were decreased as the increase of precipitation under the shade b5: soil water contents were increased as the increase of precipitation under the shade. 3. The higher the transmittance of the shade, the greater the specific leaf weight (S.L.W.) and stomatal density. In contrast, however, the contents of total chlorophyll, chlorophyll a and b, and stomatal length was decreased. There was no any significant difference light intensity of the a/b ratio of chlorophyll. 4. The highest photosynthesis was occurred in ginseng leaves grown under the shade 5% L.T.R. and net photosynthesis rates increased with increasing soil water contents. 5. Optimum condition for usable seedling yield were 5% L.T.R. and 3.3% precipitation under the shade. Useless seedling increased with increasing precipitation under the shade.

• 한국환경과학회지
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• 제25권6호
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• pp.889-895
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• 2016

In Danseong-myeon (myeon is a subdivision of), Sancheong-gun, and Sugok-myeon, Jinju City, pot seedling culture was used at the rates of 100% and 62%, respectively. Root restriction seedling culture was used relatively more frequently than pot seedling culture in Yangchon-myeon, Nonsan City, Guryong-myeon, Buyeo-gun, and Wolsan-myeon, Damyang-gun. Open-field seedling culture was used at the rates of 80% and 54% in Samnangjin-eup (eup is a subdivision of a gun), Miryang City and Ssangnim-myeon, Goryeong-gun, respectively. In Danseong, Sancheong, and Sugok, Jinju, granite soil was used as the medium for pot seedling culture at the rates of 90% and 80%, respectively. In Yangchon, Nonsan, Wolsan, Damyang, and Ssangnim, Goryeong, commercial bed soil and coir dust were used for seedling culture at the rates of 73%, 64%, and 60%, respectively. At the main production sites, the use of granite soil for seedling culture, highest rate in 2000-2005, continued to decrease; in 2011-2013, granite soil was used at the rate of 37%, while commercial bed soil and coir dust were used at the rates of 32% and 14%, respectively. The bulk density of commercial bed soil, expanded rice hulls, and coir dust was $0.11-0.16g/cm^{-3}$. Coir dust was the lightest material but had the highest and, 36.7% and 21.8%, respectively. In sandy loam soil and granite soil was low. The pH of all growth media was between 5.4 and 7.0, and the values were in the range of $0.15-0.66dS{\cdot}m^{-1}$. However it was necessary, to adjust the pH levels and enhance the of expanded rice hulls, sandy loam soil, and granite soil. Similarly, the fertilizer concentration and air permeability of coir dust need to be adjusted.

• 한국작물학회지
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• 제49권4호
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• pp.284-288
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• 2004

The response of dissolved oxygen (DO) concentrations caused significant change in root number, root length, coleoptile length, shoot length and leaf age of seedlings. The genotypic difference in the effect of DO also highly significant (P<0.01) for all of the seedling traits. The number and length of root were extremely inhibited at the condition of $0.39\pm0.09$ DO concentration. While the coleoptile elongated markedly in the lowest DO concentrations, the shoot did not develop. The root growth was improved slightly at the $1.39\pm0.27mg L^{-1}$, however, there were no difference among genotypes at these two low DO concentrations. As the DO concentration become higher, the growth of root and shoot was improved remarkably. Root number, root length and shoot length was significantly different between $20\;and\;30^{\circ}C$ in DO rich and normal conditions, the development of those traits were apparently accelerated in high water temperature, however those traits of seedlings in DO deficiency were not different between the two temperatures except for shoot length. On the other hand the coleoptile length was not affected by the stagnant water temperature; it was stimulated by the low DO concentration. The competition of DO was greater as the seedling density was increased in the stagnant water, therefore the seedlings grown under high density have long and white coleoptiles, and the growth of roots and shoots was retarded severely.

• BMB Reports
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• 제50권7호
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• pp.343-344
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• 2017

Plants are able to recognize even small changes in surrounding temperatures to optimize their growth and development. At warm temperatures, plants exhibit diverse architectural adjustments, including hypocotyl and petiole elongation, leaf hyponasty, and reduced stomatal density. However, it was previously unknown how such warm temperatures affected the early stages of seedling development. In our recent study, we demonstrated that the RNA-binding protein, FCA, is critical for sustaining chlorophyll biosynthesis during early seedling development, which is a prerequisite for autotrophic transition at warm temperatures. FCA plays a dual role in this thermal response. It inhibits the rapid degradation of protochlorophyllide oxidoreductases (PORs) that mediate chlorophyll biosynthesis. In addition, it induces the expression of POR genes at the chromatin level, which contributes to maintaining functional enzyme levels. Our findings provide molecular basis for the thermal adaptation of chlorophyll biosynthesis during the early stages of seedling development in nature.

• 한국작물학회지
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• 제33권2호
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• pp.146-156
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• 1988

기계이앙용 상자육묘에 파종량 차이에 따른 배유양분의 소모와 묘소질의 변화를 알아보고자 다수계품종인 삼강벼와 일반계품종인 동진벼를 공시하였던 결과는 다음과 같다. 1. 초장은 파종후 급속히 신장하여 10일 경에는 삼강벼, 동진벼가 각각 묘의 60, 50%에 달하였으며, 밀파할수록 점차 작아졌는데, 그 정도는 삼강벼에서 뚜렷하였다. 2. 건물중은 묘대일수가 경과할수록 완만히 증가 하였는데, 밀파할수록 그 증가 속도가 느렸다. 삼강벼, 동진벼 공히 밀파할수록 건물중의 감소가 뚜렷하였는데, 가장 박파인 75g구가 다른구보다도 건물중이 현저히 무거웠다. 3. 배유양분은 삼강벼, 동진벼가 파종후 5일 이내에 각각 68, 65%가 15일에는 각각 85, 90% 정도가 소모되었는데 완전소진시기는 삼강벼가 3.1엽기인 파종후 25∼30일, 동진벼는 3.3엽기인 파종후 25일 정도였다. 4. 묘의 부위별 당함량은 배유가 엽보다 높았으며, 묘대일수 10일에서 엽과 배유의 당함량이 최대치를 나타냈고, 파종양별 당함량 식물체부위, 묘령 및 품종에 따라 달랐다. 5. 묘의 단백질함량은 엽에서 묘대기가 진행될수록 점차 감소하여 15일에 최소치를 보였고, 배유는 파종직후 감소하여 4일에 최소치를, 5일에는 다시 증가하였다가 그 이후 감소하였고, 파종양별 차는 묘령에 따라 각각 달랐다. 6. 묘의 발근력은 30일 묘 가장 좋았으며, 묘령이 높을수록 점차 나빳으며 밀파할수록 발근력이 떨어지는 경향이었다. 7. 엽록소함량은 삼강벼가 동진벼보다 컸으며, 파종량별로는 두 품종 공히 뚜렷한 경향을 보이지 않았다.

• Plant Resources
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• 제8권2호
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• pp.91-95
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• 2005

In spring, to determine the optimal planting date and plant density of rapeseed in southern areas of Korea. $Taiwan^{\#1}$ variety for spring sowing, the highest yielding variety was grown under five different planting date and plant density. Yield components such as plant height, ear length, number of seedling stand per $m^2$, number of per ear and seed set percentage were highest at the plots with Mar. 5 of planting date and 50/20cm drilling of plant density. Yield of seed, oil, gas and 1,000 grains weight and erucic acid content were highest at the Mar. 5 of planting date and 50/20cm drilling of plant density. Judging from the results reported above, at optimum planting date and plant density of rapeseed seemed too be Mar. 5 of planting date and 50/20cm plant density in spring sowing.

• 한국작물학회지
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• 제41권1호
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• pp.34-44
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• 1996

보리 분얼성 isogenic line 4계통(Kindred, Morex)을 이용하여 파종양 및 결주율에 따른 주요 형질의 변화를 조사하였다. t. 다얼성 계통은 단간성 계통에 비하여 곡립의 수양은 46％, 엽면적지수 56％가 높았으나, 단간성 계통은 정립률이 69％ 천립중은 27％가 높았다. 2. 단단성 계통은 출수기가 4∼8일, 성숙기는 2∼3일 빨랐다. 3. 곡립수양은 수수에 따른 직선회귀에 잘 적용되어 수수의 기여도가 매우 컷다. 4. 결주율이 증가함에 따라서 1수입수 및 천립중이 다소 증가하나 수수의 감소로 곡립의 수양이 현저히 감소되었다. 5. 반면에 결주율이 증가될 때 정립률, 엽의 광합성능 및 분얼수가 증가하였다. 6. 분얼성 isogenic line이 재해에 의해서 결주가 발생시 수수가 곡립의 수양을 좌우하였다. 7. 단간성 인자의 도입, 육종 및 보급을 위해선 이들 동질유전자 계통을 포장에 다년간 반복 실험하여 보다 정밀한 평가가 이루어져야 한다.