• Journal of Environmental Science International
• /
• v.4 no.3
• /
• pp.177-186
• /
• 1995

The seasonal changes and composition of phytoplankton of the Choonsan reservior were studied from November 1990 to October 1991. 195 taxa which belong to 65 genera, 150 species, 40 varieties and 1 forms were identified. Species number during summer monthes was higher than that of other seasons. Standing crops of phytoplankton were varied from $7.8\times10^5$ cells/l to $2.2\timesl0^6$ cells/$\ell$. The dominant species were Cryptomonas erose and Trachelomonas volvoina. Chlorophyll a contents of phytoplankton was varied from $1.36\mu\textrm{g}/\ell$ to $127.46\mu\textrm{g}/\ell$. The biotic indices of phytoplankton were very similar among three sites. Saprobien-system by index of species diversity suggests that the Choonsan reservior belongs to the oligosaprophic.

• Ocean and Polar Research
• /
• v.29 no.4
• /
• pp.391-400
• /
• 2007

To identify the spatial distribution pattern of water quality in Masan Bay, Pearson's correlation as a common statistic method and Moran's I as a spatial autocorrelation statistics were applied to the hydrological data seasonally collected from Masan Bay for two years ($2004{\sim}2005$). Spatial distribution of salinity, DO and silicate among the hydrological parameters clustered strongly while chlorophyll a distribution displayed a weak clustering. When the similarity matrix of Moran's I was compared with correlation matrix of Pearson's r, only the relationships of temperature vs. salinity, temperature vs. silicate and silicate vs. total inorganic nitrogen showed significant correlation and similarity of spatial clustered pattern. Considering Pearson's correlation and the spatial autocorrelation results, water quality distribution patterns of Masan Bay were conceptually simplified into four types. Based on the simplified types, Moran's I and Pearson's r were compared respectively with spatial distribution maps on salinity and silicate with a strong clustered pattern, and with chlorophyll a having no clustered pattern. According to these test results, spatial distribution of the water quality in Masan Bay could be summed up in four patterns. This summation should be developed as spatial index to be linked with pollutant and ecological indicators for coastal health assessment.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.2
• /
• pp.131-135
• /
• 2004

To find out the responses of soybean genotypes in terms of different levels of irrigation with the aim of evaluating the growth, yield, and its optimum levels of irrigation, an experiment was conducted at the Field of Crop Botany Department, Bangladesh Agricultural University, Mymensingh during the period from November 2000 to February 2001. Five levels of irrigation viz. $\textrm{I}_0$: no irrigation, $\textrm{I}_1$: one time irrigation at 20 days after sowing (DAS), $\textrm{I}_2$:two times irrigation at 20 and 40 DAS, $\textrm{I}_3$: three times irrigation at 20, 40, and 60 DAS, and $\textrm{I}_4$: four times irrigation at 20, 40, 60, and 80 DAS and three genotypes of soybean viz. BS-3, BS-16, and BS-60 were used in this experiment. The crop was grown in a split plot design having three replications. The plant height, leaf area index, crop growth rate, shoot dry weight, branches $\textrm{plantI}_{-1}$, filled pods $\textrm{plantI}_{-1}$, seeds $\textrm{plantI}_{-1}$, seed yield, and harvest index were influenced significantly by irrigation and these were found to be highest at three times irrigation except branches $\textrm{plantI}_{-1}$. The chlorophyll content increased but empty pods $\textrm{plantI}_{-1}$ decreased with increase in irrigation levels. Genotypes of soybean varied significantly in terms of growth attributes at various growth stages except shoot dry weight at 90 DAS. The genotype BS-3 performed better compared to other genotypes and gave maximum seed yield.

• Applied Biological Chemistry
• /
• v.14 no.2
• /
• pp.149-156
• /
• 1971

Variations of carotenoid and chlorophyll during the course of after-ripening in hotpepper fruits were studied: 1. Carotenoid pigments were fractionized into six fragments by means of column chromatography and each of six were applied to the TLC. By these procedures 30 kinds of carotenoids were identified among 54 kinds of different separations. 2. Total carotenoids increased very rapidly in cli. stage. And when compared group by group, Diol showed highest in amounts as well as in increasing index. 3. Decrease of phytoene in post-cli. stage and notable increase of capsanthin, capsorubin and violaxanthin amounts in carotenoid, as major pigments, were remarkable one. 4. Total amounts of chlorophyll a and b showed decreasing tendency during after-ripening and, finally, disappeard at the post-cli. stage.

• Journal of the East Asian Society of Dietary Life
• /
• v.17 no.5
• /
• pp.671-677
• /
• 2007

This study examined the relationship between chlorophyll(Chl) and ascorbic acid(ASA) as an index of freshness for vegetables, when the general consumers purchase several kinds of vegetables at the market. The leaves and fruits of several types of vegetables were divided into top, middle, and basal sections. Chl was determined by a spectrophotometer, and ASA was analyzed by high-performance liquid chromatography. For the vegetable sections, we found that Chl and ASA levels were highest in the top sections, followed by the middle, and were lowest in the basal portions. For the relationship between Chl and ASA in vegetables, there were seven classifications including high Chl(above 80mg/100g of fresh weight) and high ASA(above 80 mg/100 g of fresh weight) for mallow, and kail; the second group had high Chl and low ASA(below 80 mg), such as in spinach, burdock, and perilla leaves; the third group contained medium Chl($40{\sim}80mg$) and medium ASA($40{\sim}80mg$) levels, such as for gonddalbee, angelica, pumpkin leaf and coriander; the fourth group had medium Chl and low ASA levels, as in crown daisy and lettuce; the fifth group contained low Chl(below 40 mg) and high ASA, such as in hot peppers and parsley; the sixth group had low Chl and medium ASA levels, and included broccoli, pak choi, and sweet peppers; finally the seventh group contained low Chl and low ASA levels, as in dropwort, young radishes, shallots, cucumbers and swiss chard.

• Journal of Korean Society on Water Environment
• /
• v.21 no.4
• /
• pp.360-367
• /
• 2005

We have performed to analyze the trophic state resulting of Lake Yongdam as a result of water quality and nutrient concentration. Lake Yongdam is artifitial multi-purpose Dam resulting from the floods of 2001. The water quality of Lake Yongdam may affect the status of the Geum river basin including the Daecheong reservoir. It is necessary to understand the trophic state to assess water quality until stability after flooding. Water quality was surveyed using depth and hydraulic condition analysis. Further density flow was estimated for stratification and trophic state of Lake Yongdam by chlorophyll ${\alpha}$ concentration (2001~2004). And Environmental factors on chlorophyll ${\alpha}$ concentration were analyzed statistically. Trophic state was evaluated as the oligotrophic state at the main stream of the reservoir and eutrophic state at the upper stream in 2001, but evaluated as eutrophic state in 2002 and 2003 by TSI of Aizaki. From the results of multiple regression analysis using stepwise method, chlorophyll ${\alpha}$ concentration was shown to be very significant when nutrient concentration is high upon initial filling of the Dam. Chlorophyll ${\alpha}$ concentration varied according to sample site, season and year. Concentration were high in the upper stream of Lake Yongdam 4, algae bloom in these watershed were affected by location and high nutrient levels in the summer season which have in turn increased phytoplankton bloom into the reservoir.

• Journal of Plant Biotechnology
• /
• v.48 no.2
• /
• pp.115-122
• /
• 2021

Aspilia africana (Pers) C.D.Adams, a plant used for centuries in many African countries to treat diseases such as osteoporosis, malaria, tuberculosis, and diabetes, is of great pharmaceutical interest, yet there is limited scientific literature on its germination and growth. This research paper describes the effects of different commercial soils on the germination, growth, and chlorophyll content of A. africana. The germination parameters assessed included final germination percentage (FGP), mean germination time (MGT), and germination index (GI). Shoot length, leaf number, and fresh and dry weights were some of the parameters used to assess A. africana growth. The FGP was low and did not vary significantly; the MGT was 7 ~ 10 days; and the GI was significantly higher in PPS soil at 4.61 ± 0.332 days. Aspilia africana plants in HS:PPS soil showed the best overall growth, producing the highest mean leaf number (18.00 ± 1.129), longest mean shoot length (202.43 ± 13.451 mm), and highest mean fresh and dry weights (7.08 ± 1.061 g and 0.629 ± 0.112 g, respectively). The highest chlorophyll content in leaves of A. africana under HS:PPS conditions suggested a higher photosynthetic potential of plants in this soil. The best growth performance of A. africana in the HS:PPS soil could be attributed to a higher amount of certain mineral nutrients such as nitrogen, potassium, and phosphorus in the HS:PPS soil compared to the other soil categories. It is unclear why the FGP of A. africana was low and we recommend an exclusive study to investigate this further.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.24 no.1
• /
• pp.97-110
• /
• 2021

Vegetation index information is an important figure that is used in many fields such as landscape architecture, urban planning, and environment. Vegetation may vary slightly in vegetation vitality depending on photosynthesis and chlorophyll content. In this study, a range of vegetation worth preserving in the Taehwa River water system was determined, and hyperspectral images of drones were acquired (August, October), and the results were presented through DVI(Normalized Defference Vegetation Index), EVI(Enhanced Vegetation Index), PRI(Photochemical Reflectance Index), ARI (Anthocyanin Reflectance Index) index analysis. In addition, field spectral data and VRS-GPS(Virtual Reference System-GPS) surveys were performed to ensure the quality and location accuracy of the spectral band. As a result of the analysis, NDVI and EVI showed low vegetation vitality in October, -0.165 and -0.085, respectively, and PRI and ARI increased to 0.011 and 7.588 in October, respectively. For general vegetation vitality, it was suggested that NDVI and EVI analysis were effectively performed, and PRI and ARI were thought to be effective in analyzing detailed characteristics of plants by spectral band. It is expected that it can be widely used for park design and landscape information modeling by using drone image information construction and vegetation information.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.3 no.S1
• /
• pp.77-90
• /
• 1997

the observations in situ and the seawater analyses were conducted in July and August, 1996 for the purpose of evaluating the characteristics of seawater quality centered on eutrophication in Mokpo harbour. By applying the OECD standards of trophic classification to the parameters such as secchi depth, total inorganic nitrogen, phosphate phosphorus and chlorophyll-a, the trophic level of seawater in Mokpo harbour was evaluated to be in eutrophic state in summer. By the estimation of pollution index with relation to eutrophication, the seawater quality of Mokpo harbour was evaluated to be under the regular grades and this evaluation was found to be different from the results of evaluation obtained by the environmental index of single parameter, chemical oxygen demand. By the estimation of eutrophication index, the seawaters of Mokpo harbour were shown to have the high potentiality of red tide occurrence.

• Horticultural Science & Technology
• /
• v.34 no.6
• /
• pp.818-829
• /
• 2016

This study evaluated the responses of 18 potato cultivars to three levels of salinity stress (electrical conductivity, EC: 1.0, 4.0, and $8.0dS{\cdot}m^{-1}$). Stem, leaf, root, chlorophyll, tuber yield, and proline content were investigated and statistically analyzed using analysis of variance (ANOVA) and correlations. Stem number and stem diameter were not affected by salinity, but stem length and aerial weight showed highly significant responses to salinity. Aerial weight decreased with increasing salinity levels in most cultivars, while it increased in some the cultivars 'Daejima', 'Goun', 'Haryeong', and 'LT-8'. Leaf number, leaf area index, and leaf weight were most significantly affected by salinity and the cultivar ${\times}$ salinity interaction. Root length, root weight, total chlorophyll and chlorophyll a were affected by salinity, but not by the cultivar ${\times}$ salinity interaction. The opposite trend was shown in chlorophyll b. Although there was great variability among cultivars, tuber yield decreased in all cultivars, and was most significantly influenced by salinity and the cultivar ${\times}$ salinity interaction. 'Superior', 'Kroda', 'Romana', and 'Duback' gave better tuber yields under salinity at EC 4.0 and $8.0dS{\cdot}m^{-1}$ than the cultivars with better aerial weights. Proline content was increased by salinity in all cultivars, and was more remarkable in the cultivars with better aerial weights than in cultivars such as 'Superior' and 'Kroda' with better tuber yields. Leaf number, leaf area index, leaf weight, and root length parameters were considered to be useful criteria in the evaluation of salt tolerance because of their high positive correlation with tuber yield; however, given its negative correlation with tuber yield under high salinity, proline content was not. Salinity tolerances varied greatly among potato cultivars. The low correlation between growth and yields of aerial parts under high salinity suggests that, in commercial agriculture, it might be more practical to compare relative yields to controls. Additionally, 'Superior', 'Kroda', 'Romana', and 'Duback' might be very useful cultivars to use in breeding programs to develop salinity-tolerant potatoes, as well as for sustainable potato production in saline areas.