- ENGLISH
- P-ISSN2287-8327
- E-ISSN2288-1220
- SCOPUS, KCI
27권 2호
초록
Abstract
There are 474 species of native vascular plant distributed in offshore islands in Shandong Province, which belong to 262 genera and 82 families. The distribution types of genera of seed plant were classified into 15 types. Temperate characteristic is dominant in the flora of offshore islands and tropical characteristic ranks secondary. Therefore, some islands play the role of stepping islands. Furthermore, 98.85% of the total genera are monotypic or bitypic which shows the offshore habitat heterogeneity in Shandong Province.
초록
Abstract
To elucidate the trophic relationships within a subtropical wetland, the profile of fatty acids in producers, consumers and sediments of the mangrove forest and intertidal mudflat was studied. Results indicated a close relationship in fatty acid profiles between the mangrove plants Aegiceras corniculatum and Avicennia marina and the sesarmid crab Sesarma bidens, and between the fiddler crab Uca arcuata and diatoms. The fatty acid profile of the mudskippers Boleophthalmus pectinirostris and Periophthalmus cantonensis, however, showed a mixed diet of diatoms, macroalgae, protozoa and crabs. Seasonal changes in fatty acid profiles in mangrove plants, sediments and sesarmid crabs were noted. The implication of using fatty acids as tracer of trophic relationships was discussed.
초록
Abstract
This study was carried out to evaluate soil carbon and nutrient storage of three adjacent coniferous plantations (Larix leptolepis, Pinus densiflora and Pinus rigitaeda) growing on a similar site with a same planting age (42-year old) in the Sambong Exhibition Forests, Hamyang-gun, Gyungsangnam-do. The soil carbon concentration among three plantations was not significantly different in 0∼10 cm soil depth, but other two depths (10∼20 cm and 20∼30 cm) showed higher carbon concentration in P. densiflora plantation than the other two plantations. The exchangeable cation concentrations (Ca and Mg) in 0∼10 cm depth were significantly lower in L. leptolepis plantation than in the other two plantations, while nitrogen and phosphorus concentrations were not significantly different among three plantations except for nitrogen at 10∼20 cm depth in P. rigitaeda plantation. Soil carbon storage in 0∼20 cm depth of three plantations was unaffected by the stand types. Soil nutrient storage was not significantly different at each depth except for nitrogen storage at 10∼20 cm depth in P. rigitaeda plantation because of the variation of bulk density and coarse fragment. This result demonstrates that soil carbon and nutrient concentrations among the plantations on a similar soil condition can be altered significantly by tree species effects over 40 years after plantation establishment.
초록
Abstract
Movement of shorebirds for roosting was studied to find their response to insufficient roosting area on Ganghwa Island. It was taken from two kinds of aspects of population fluctuation and direct observation of movement from March to October in 2002. Based on the data from their weekly fluctuation and flight observation, shorebirds on Ganghwa Island moved to roosts located far away. Shorebirds feeding at southern Ganghwa Island moved to Yeongjong Island for roosting during the spring tide period. High tide count showed that the number of shorebirds on Yeongjong Island increased strikingly, while the number of birds on Ganghwa Island decreased. As the tide level increased, the number of shorebirds on Ganghwa Island decreased in the fall migrating season (rs =-0.81, p<0.001), whereas that on Yeongjong Island was not correlated significantly. Direct observation showed that some of the birds on the upper tidal zone of Ganghwa Island moved directly to the northern mudflat of Yeongjong Island during the flowing tide or dropped by flat zone on Seondu-ri. Insufficient coastal wetlands on Ganghwa Island induced them to move away from the island for roosting place and to endure costly flight energy expenditure. The development of wetlands on the southern Yeongjong Island would make them have no place available to roosts. Therefore this study proposes that shorebird roosts on Ganghwa Island should be created to conserve their habitat.
초록
Abstract
Soil respiration rate was measured from March to November 2003 using the KOH absorption method in Pinus densiflora, Quercus variabilis, Platycarya strobilacea stands in Jinju, Gyeongnam Province. Throughout the study period, average soil temperature and moisture content were 16.2℃, 25.1% for P. densiflora stand, 17.1℃, 24.3% for Q. variabilis stand, and 17.6℃, 25.1% for P. strobilacea stand, respectively. The seasonal fluctuations of soil respiration rate increasing in summer and decreasing in winter, which there were strong positive correlations of soil respiration and soil temperature in all study stands. However, there were no significant correlations between soil moisture and soil respiration. Soil respiration rates throughout the study period ranged from 0.12 to 0.77 for P. densiflora stand, 0.23 to 1.37 for Q. variabilis stand, and 0.30 to 1.47g CO2․m-2․hr-1 for P. strobilacea stand, respectively. Mean soil respiration rates in P. densiflora, Q. variabilis, P. strobilacea stands were 0.43, 0.80, and 0.90 g CO2․m-2․hr-1, respectively. The Q10 values were 2.38 for P. densiflora stand, 2.11 for Q. variabilis stand, and 2.07 for P. strobilacea stand. Annual total soil respiration was 24 for P. densiflora stand, 49.3 for Q. variabilis stand, and 55.3 t CO2․ha-1․yr-1 for P. strobilacea stand, respectively.
초록
Abstract
Decay rate and nutrient dynamics during decomposition of oak (Quercus acutissima) branches were investigated for 33-months in Kongju, Korea. After 33-months, remaining weight of B1, B2 and B3 was 44.5%, 58.5% and 55.37%, respectively. Decomposition constant (k) for B1, B2 and B3 was 0.294/yr, 0.195/yr, 0.215/yr, respectively. N concentration in decomposing oak branches increased in all diameter classes. After 33-months, remaining N in B1, B2 and B3 was 101.2%, 91.9%, 104.4%, respectively. P concentration in decomposing oak branches increased in B1 and B2, and there was no immobilization period. After 33-months, remaining P in B1, B2 and B3 was 57.2%, 74.4%, 53.9%, respectively. K concentration in decomposing oak branches decreased significantly. Remaining K in B1, B2 and B3 was 7.7%, 17.1% and 17.2%, respectively, which was significantly lower than other nutrients. Ca concentration in decomposing oak branches increased in B2 and B3. After 33-months, remaining Ca in B1, B2 and B3 was 58.5%, 47.8% and 75.2%, respectively. Initial concentration of Mg in oak branch was higher in smaller diameter class. After 33-months, remaining Mg in B1, B2 and B3 was 44.3%, 57.9% and 47.7%, respectively.
초록
Abstract
We developed the estimation model for the vegetation developmental processes on the severely burned slope areas after forest fire in the east coastal region, Korea. And we calculated the vegetation indices as a useful parameter for the development of land management technique in the burned area and suggested the changes of the vegetation indices after forest fire. In order to estimate the woody standing biomass in the burned area, allometric equations of the 17 woody species regenerated by sprouter were investigated. According to the our results, twenty year after forest fire need for the development to the normal forest formed by 4 stratum structure, tree, sub-tree, shrub and herb layer. The height of top vegetation layer, basal area and standing biomass of woody species show a tendency to increase linearly, and the ground vegetation coverage and litter layer show a tendency to increase logarithmically after forest fire. Among vegetation indices, Ivc and Ivcd show a tendency to increase logarithmically, and Hcl and Hcdl show a tendency to increase linearly after forest fire. The spatial variation of the most vegetation factors was observed in the developmental stages less than the first 5 years which were estimated secondary disaster by soil erosion after forest fire. Among vegetation indices, Ivc and Ivcd were the good indices for the representation of the spatial heterogeneity in the earlier developmental stages, and Hcl and Hcdl were the useful indices for the long-term estimation of the vegetation development after forest fire.
초록
Abstract
Tomato (Lycopersicon esculentum) seedlings exposed to various concentrations of CdCl2 (0-100μM) in the nutrient solution for up to 9 days were analyzed with the seedling growth, H2O2 production, glutathione levels and activity changes of enzymes related to H2O2 removal. The growth of seedlings was inhibited with over 50 μM Cd, whereas the levels of H2O2 and glutathione were enhanced with Cd exposure level and time. Meanwhile, Cd exposure increased the activities of catalase (CAT) and glutathione reductase (GR) but decreased the activities of dehydroascorbate acid reductase (DHAR) and ascorbate peroxidase (APX) in both leaves and roots. These results suggest that the altered activities of antioxidant enzymes particularly involved in the H2O2 removal and the subsequent H2O2 accumulation could induce the Cd-induced phytotoxicity.
초록
Abstract
Coarse woody debris (CWD, ≥ 5 cm in maximum diameter) is an important functional component, especially to nutrient cycling in forest ecosystems. To compare mass and nutrient dynamics of CWD in natural oak forests, a two-year study was conducted at Quercus serrata and Q. variabilis stands in Yangpyeong, Kyonggi Province. Total CWD (snag, stump, log and large branch) and annual decomposition mass (Mg/ha) were 1.9 and 0.4 for the Q. serrata stand and 7.5 and 0.5 for the Q. variabilis stand, respectively. Snags covered 72% of total CWD mass for the Q. variabilis stand and 42% for the Q. serrata stand. Most of CWD was classified into decay class 1 for both stands. CWD N and P concentrations for the Q. variabilis stand significantly increased along decay class and sampling time, except for P concentration in 2002. There were no differences in CWD N concentration for the Q. serrata stand along decay class and sampling time. However, CWD P concentration decreased along sampling time. CWD N and P contents (kg/ha) ranged from 3.5~4.7 and 0.8~1.3 for the Q. serrata stand to 22.8~23.6 and 3.7~4.7 for the Q. variabilis stand. Nitrogen and P inputs (kg/ha/yr) into mineral soil through the CWD decomposition were 0.7 and 0.3 for the Q. serrata stand and 1.6 and 0.3 for the Q. variabilis stand, respectively. The number of CWD and decay rate were main factors influencing the difference in CWD mass and nutrient dynamics between both stands.