• ALGAE
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• v.23 no.3
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• pp.241-250
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• 2008

Since seagrasses in the coastal and estuarine ecosystems achieve high levels of production, they require high inorganic carbon and nutrient incorporation. Thus, seagrasses may play a significant role in carbon and nutrient cycling in the coastal and estuarine ecosystems. To examine growth dynamics of Zostera marina L. environmental factors such as underwater irradiance, water temperature, and salinity, and biological parameters such as shoot density, biomass, shoot morphology, and leaf productivity were measured in two bay systems (Jindong Bay and Gamak Bay) on the southern coast of Korea. While underwater irradiance did not show distinct seasonal trend, water temperature at both sites exhibited clear seasonal trend throughout the experimental period. Shoot density increased dramatically during winter due to the increased seedlings through germination of seeds in Jindong Bay and due to the increased lateral shoots in Gamak Bay. Eelgrass biomass increased during winter and decreased during summer. Maximum biomass in Jindong Bay and Gamak Bay was 250.2 and 232.3 g dry weight m–a2, respectively. Carbon incorporation into the eelgrass leaf tissues was estimated from productivity and leaf tissues carbon content. The calculated annual carbon incorporations at the Jindong Bay and Gamak Bay sites were 163 and 295 g C m–`2 y–`1, respectively. This high carbon incorporation into seagrass tissues suggests that seagrass habitats play an important role as a carbon absorber in the coastal and estuarine ecosystems.

• The Korean Journal of Ecology
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• v.24 no.5
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• pp.309-313
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• 2001

This research was conducted to test cadmium tolerance by five speices of native herbs for screening cadmium tolerance plant. We examined germination rate, root and shoot growth rate of seedling, fresh biomass of native herbs exposed to cadmium solution for 14 days. Especially, germination rate of Abutilon avicennae and Amaranthus retroflexus was over 90% in all concentration, but germination rate of Aeschynomene indica, Echinochloa crus-galli var. oryzicola and Echinochla crus-galli var. frumentacea began to decrease when they exposed to 15 mgCdSO₄ /L. The higher the Cd concentration, the length of root, shoot grew lower. The fresh biomass of Echinochloa crus-galli var. oryzicola, Echinochla crus-galli var. frumentacea and Amaranthus retro-flexus were not so different from each control, but those of Abutilon avicennae and Aeschynomene indica began to decrese greatly when exposed to 60 mgCdSO₄ /L. EC/sub 50/(Effective Concentration 50%) of Abutilon avicennae, Aeschynomene indica and Amaranthus retroflexus was 44.6∼77.5 mgCdSO₄ /L for root growth, 38.6∼114 mgCdSO₄ /L for shoot growth, 60∼107.5 mgCdSO₄ /L for fresh biomass. Among the native herbs, sensitivity of cadmium ordered as root length > fresh biomass > shoot length. These results indicate that Abutilon avicennae is a tolerant species for cadmium.

• Journal of Soil and Groundwater Environment
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• v.6 no.4
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• pp.3-11
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• 2001

To select a suitable indigenous plant for the phytoremediation of TNT contaminated soil, eight representative species of native grasses were tested to identify TNT toxicity thresholds. The threshold was determined based on various factors including cumulative seed germination, root and shoot length, fresh biomass, and the amount of water uptake under various TNT concentrations. Phytotoxic effect of TNT on plants was increased with the increase in TNT concentration but the degree was varied between grass species. Concentrations up to 60-80mgTNT/liter did not affect germination of Abutilion avicennae, Echinochioa crusgalli var. frumentacea, and Aeschynomene indica. Phytotoxicity threshold inhibition (50%) of Abutilion avicennae, schinochioa crusgalli var. frumentacea, Aeschynomene indica were 5-40mgTNT/liter for root length, 50-73mg TNT/Liter for shoot length and 68-99mgTNT/Liter for fresh biomass during 14 days of seedling exposure. Root and shoot growth as well as fresh biomass decreased as TNT concentration increased. In addition, the amount of water uptake decreased with increasing TNT concentration in Abutilion avicennae and Aeschynomene indica. Comparison of toxicity thresholds for the tested grass species showed that sensitivity of plants to TNT was in the order of root length > shoot length > fresh biomass > germination rate. From these results, we concluded that Abutilion avicennae and Aeschynomene indica had tolerance to TNT among the species tested.

• Journal of Forest and Environmental Science
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• v.39 no.2
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• pp.96-104
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• 2023

The successful restoration program requires a comprehensive understanding of variables influencing seedling efficiency. Below-ground is hypothesized to have a major impact on seedling performance of species when planted in agriculture, and degraded areas with different types of mulching. This study investigated on Sg. Terla Forest Reserve in Cameron Highlands Pahang, Malaysia. In this study randomized complete block design (RCBD) was used. The excavation method was applied to study the root system development, above, and below ground biomass distributions under different types of mulching: coconut mulching (CM), oil palm mulching (OM), plastic mulching (PM) and control (CK). The root diameter, main root length, lateral root length, root coiling, and root direction toward to sun were recorded. The results in this study indicate that mulching had significant effect on root diameter, main root length, and root distributions among treatments while for lateral root length, root: shoot ratio, dry biomass distributions, and above and below ground biomass did not showed significant effect among treatments. The highest values for root diameter, lateral root length, main root length, root distributions, dry biomass distributions and above and below ground biomass were showed in CM treatments. However 75% of root coiling was observed in seedlings between treatments.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.276-288
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• 2013

The present study investigates the effects of elevated soil nitrogen on growth and decomposition of Oryza sativa shoots. The plants were cultivated in greenhouse until leaf senescence and the total biomass of the plant increased 1.9 times at nitrogen addition plot. Total C and N content in shoot increased; however, lignin, C/N, and lignin/N levels decreased in the N-treated soil. The shoot litters collected from the control and N-treated soil were tested for decay and microbial biomass, $CO_2$ evolution, and enzyme activities during decomposition on the control and N-treated soil at $25^{\circ}C$ microcosm. The remaining mass of the shoot litter was approximately 6% higher in the litter collected from the control soil (53.0%) than the litter collected from high N-treated soil (47.1%). However, the high N-containing litter exhibited faster decay in the control soil than in the N-treated soil. The litter containing high N, low C/N, and low lignin/N showed a higher decomposition rate than that of low quality litter. The N-addition showed decreased microbial biomass C and dehydrogenase activity in soil; however, it exhibited high microbial biomass N and urease activity in soil. When the high N-containing litter decays on the N-treated soil, the microbial biomass C increased rapidly at the initial phase of decomposition and decreased thereafter, and dehydrogenase activity was less that of other treatment; however, there was no effect on the microbial biomass N. The urease in the decomposing litter was highest during the early decomposition stage and dramatically decreased thereafter. The present findings suggested that the N-addition increased N content in litter, but inhibited the decomposition process of above-ground biomass in terrestrial ecosystems.

• Korean Journal of Environmental Biology
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• v.20 no.4
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• pp.339-346
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• 2002

From March 1998 to August 2000, the phonology and morphometrics change of Zostera caespitosa Miki were examined at the Duksan Port in the eastern coast of Korea. Morphometric characteristics (shoot height, leaf length, sheath length, leaf width, and number of leaf per shoot), size and number of reproductive structures (spathe, spadix, and seeds), shoot density, biomass and physiochemical parameters (water temperature and nutrient concentrations) were measured. Significant differences between months (p < 0.05) existed for morphometric characteristics except for sheath length. The sequence of shoot heights clearly showed cyclical annual variation with water temperature. Vegetative shoots of Z. caespitosa were present throughout the year, but reproductive shoots were rarely occurred from mid January to early April in water temperature of $9-12^\circ{C}$. Flowering in the spathe began in mid February, and seed maturing was occurred in early April. Water column nitrate and phosphate concentration showed seasonal variation, but ammonia concentration was variable with season. Relationships between shoot morphometrics and physiochemical parameters were not significantly correlated but water temperature seemed to regulate the re-productive phase and annual life cycle. The mean shoot density and above biomass of the populations were $511.6\pm{25.6}\;shoots\;m^{-2}$ and $413.4\pm{19.8}\;g\;dry\;wt\;m^{-2}$, respectively.

• Journal of Wetlands Research
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• v.14 no.4
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• pp.597-605
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• 2012

This study was conducted in order to determine changes in the growth responses of Quercus serrata and Q. aliena which are potential natural vegetation of riverine in Korea under four light gradients within ambient and elevated $CO_2$ concentration and temperature levels. As a result, growth responses of two species were affected by light factor. Aboveground, belowground, plant biomass and root:shoot ratio of two species grown under the control and treatment were increased in the highest light level. Plant biomass and root:shoot ratio of two oak species were not significantly affected by elevated $CO_2$ and temperature, while aboveground biomass of them was lower in the treatment than control. Belowground biomass of Q. serrata was lower in the treatment than control under the gradients that are more than 70% of light level. As light intensity increases, elevated $CO_2$ and temperature promoted root growth of two oak species but had a negative effect on aboveground growth. According to the principal component analysis(PCA), two oak species were discriminatively arranged based on factor 1 and 2. Also, the reactions towards the ambient and elevated $CO_2$ and temperature were slightly different. It is clearly visible that all features relied on axis 1 and axis II are highly correlated with most variables except for stem and shoot length.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.68-74
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• 2010

The present study was conducted to investigate growth performance and ascorbic acid contents of Allium victorialis var. platyphyllum, Ligularia fischeri, and L. stenocephala growing under four different light intensity regimes (full sun, and 64~73%, 35~42%, 9~16% of full sun). The leaf area and total biomass of Allium victorialis var. platyphyllum were highest in 35~42% of the full sun. However, the leaf area and total biomass were highest in 64~73% of the full sun in Ligularia fischeri, and L. stenocephala. The leaf thickness decreased with increasing shading in all three wild vegetables. The growth of root comparing to that of shoot decreased as shading increased, and as the result, the ratio of shoot biomass to root biomass increased. Ascorbic acid contents were higher in Allium victorialis var. platyphyllum than in Ligularia fischeri and L. stenocephala. Allium victorialis var. platyphyllum showed the highest contents of ascorbic acid in 35~42% of full sun. Whereas Ligularia fischeri and L. stenocephala showed the highest in 64~73% of full sun.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.1
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• pp.59-65
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• 2002

The community of common reed (Phragmites australis) is expanded by the development of new shoots from nodes of rhizomes and old shoots in natural environments. We developed the useful technique to construct reed mats of floating islands developed from shoot nodes of reeds for the purpose of the rapid stabilization of vegetation and the application of adapted plants with their specific environmental conditions. The vegetation development was compared in the floating islands planted with the different reed samples. The reed samples were consisted of four types : long shoot in the length of 100 cm (AG I), short shoot of 15 cm (AG II), long rhizome of 100 cm (BG I) and short rhizome of 15 cm (BG II). Shooting started earlier in BG I and BG II than in AG I and AG II. But the rate of shooting was higher in AG I and AG II than in BG I and BG II. After four weeks, AG I and AG II were higher than BG I and BG II in the biomass and density of newly developed shoots. These results showed that the construction of sod mats by planting only reed shoots was a useful technique to develop vegetation on the floating islands.

• Journal of Korean Society of Forest Science
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• v.112 no.2
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• pp.127-135
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• 2023

This study aimed to develop biomass allometric equations and estimate carbon emission factors, such as the wood density, biomass-expansion factor, and root-to-shoot ratio, for Platanus occidentalis and Metasequoia glyptostroboides planted in urban areas. Twenty M. glyptostroboides and 25 P. occidentalis trees were harvested, and the dry weights and stem volumes of stems, branches, leaves, and roots (>5 mm) were measured. The wood densities of M. glyptostroboides and P. occidentalis were 0.293 ± 0.008 g cm^-3 and 0.509 ± 0.018 g cm^-3, and the biomass-expansion factors were 1.738 ± 0.031 and 1.561 ± 0.035. The root-to-shoot ratios were 0.446 ± 0.009 and 0.402 ± 0.012. The uncertainty tests (coefficient of variation, %) gave 2.8% and 3.5% values for wood density, 1.8% and 2.3% for biomass-expansion factor, and 2.1% and 2.9% for root-to-shoot ratio, respectively. Among the developed allometric equations, Model I using the diameter at breast height (DBH) was suitable. The allometric equations of M. glyptostroboides and P. occidentalis above ground were y = 1.679 (DBH)^1.315 and y = 0.505 (DBH)^1.896, and the allometric equations of the root and total were y = 0.746 (DBH)^1.315, y = 0.301 (DBH)^1.751, y = 2.422 (DBH)^1.316, and y = 0.787 (DBH)^1.858. If the carbon-emission factors of this study and biomass allometric equations of the three developed models are used to estimate the carbon storage and biomass of urban forests, errors caused by not considering the use of fixed factors and the environmental differences can be reduced.