• The Korean Journal of Ecology
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• 제20권6호
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• pp.405-411
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• 1997

Feeding behavior of the Russet Sparrow Passer rutilans was studied in two different types of habitats, shelter belts and isolated forests, in south-eastern Hokkaido, Japan, during the breeding seasons of 1995 and 1996. Predominant foods were determined as Caterpillar, Coleoptera, Diptera, Ephemeropera, Odonate and some other insects. The composition of the nestiling foods were not the same by season, region, and year. Larger foods in size were used by birds in isolated forests more frequently than in shelter belts. Amount of food per feeding was significantly larger in isolated forests than in shelter belts. Although food supply were more abundant in isolated forests than in shelter belts, the feeding frequency did not significantly differ between these two habitats. The nest density was higher in isolated forests than in shelter belts. Results of this study indicate that when the feeding condition is poor, birds tend not show specific food selection behavior, the feeding range is therefore larger, and the feeding interval is longer. Contrarily, the birds show a specific food selection behavior when they are in good feeding condition, the feeding range is therefor smaller and the feeding interval decreases.

• The Korean Journal of Ecology
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• 제21권4호
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• pp.401-403
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• 1998

Body size of the Russet Sparrow (Passer rutilans) was investigated during the breeding seasons of 1994 to 1996, in south-eastern Hokkaido, Japan. Both male and female arrived slightly earlier in isolated forests than in shelter belts during the study. Wing lengths of males and females were significantly longer in isolated forests than those in shelter belts, but the other body size characteristics were not differ significantly. The results indicate habitat selection of the birds depended on their body constructions, in which wing length as an indicator, body size may be an important factor. Large-sized birds select the better quality habitat than birds of small size.

• The Korean Journal of Ecology
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• 제5권4호
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• pp.211-221
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• 1982

Tracheophyta produced in this island consisted of 77 families, 180 genera, 214 species, 28 varieties and 1 forma, lauriligonosa of which comprised species and varieties. As in the case of neightboring Nowhado, Bogildo and Choungsando islands, this island was also a supply source of fuel woods consumed mainly in Mokpo and Wando cities during the period of Japanese rule and for about a decade after the liberation of Korea in 1945. Consequently it was once almost deforested, but its restorative proces has successfully taken place for about 25 years and now Pinus thunbergii is distributed dominantly all over the mountains and plains of the island. The forest of the Seonangdang (shrine of a tutelary diety) at Bijari and the windbreak forests at Minari, Maengseonri and Soan High School compound were formed with the old trees of laurilignosa, such as Machilus thunbergii, Machilus japonica, Castanopsis cuspidata and Camellia japonica. These shelter belts were relatively well preserved.

• 물과 미래
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• 제5권2호
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• pp.6-16
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• 1972

It has been well studied and known that the yields from the rice fields irrigated by the cold water such as the water directly flowing in from mountain valleies, underground water and subground water are largely influenced by the water temperature. However, the best method of raising water temperature has not yet been established. This is because there are some essentially difficult problems associated. When we examine the effects of $1^{\circ}C$ rise in the water temperature under natural condition on rice growing, the necessity of this line of study is verified. The results of Mihara's study show that rice bears its fruits at the water temperature above $19^{\circ}C$ and the difference of $1^{\circ}C$ in the range of $19^{\circ}C$ to $22^{\circ}C$ can produce the 20% of difference in yields. Because of these facts, most farmers have made use of water temperature raising ponds, zigzag waterways and shelter belts. But the most important factor in raising water temperature has been found to be the heat loss due to evaporation. Recently, a good deal of experiment on raising water temperature and soil temperature by reducing the evaporation are being carried out all over the world. The reduction of evaporation does not only reduce heat loss, from the surface but also reduce the loss of water. Present study is aimed to determine the efficiency of different chemicals by which monomolecular films are formed over different surfaces such as water surface, soil surface and the surface of plant leaves with a purpose of preventing the transpiration, and aimed to observe the effects of the temperature rise and its influence on growing state as well as the durability of the plants under drought condition.