巻号一覧
85 巻, 1 号
選択された号の論文の7件中1～7を表示しています
- |<
- <
- 1
- >
- >|
-
川上 健三1976 年 85 巻 1 号 p. 1-9
発行日: 1976/02/25
公開日: 2009/11/12
ジャーナル フリーWith the convening of the Third United Nations Conference on the Law of the Sea, it appears that the concept on an economic zone extending up to 200 nautical miles out to sea is receiving wide support. In this essay a general observation will be made in the first place as to the arguments advanced so far in respect to the question of economic zone and it is then intended to make clear the geographically controversial points that are involved in the question of establishing such an economic zone.抄録全体を表示PDF形式でダウンロード (1536K) -
木下 誠一1976 年 85 巻 1 号 p. 10-27
発行日: 1976/02/25
公開日: 2010/02/25
ジャーナル フリーScientific expeditions in permafrost regions were carried out (1) Yakutsk, Siberia in the middle of August, 1972 and (2) Alaska and North Canada from the middle of June to the end of July, 1974.
(1) Yakutsk, Siberia
Field observations were carried out on permafrost around Lake Surdakh, which is located 250 km northeast from Yakutsk, Siberia. Lake Surdakh is an alas, which is a depression formed by a thermokarst development in which local deep thawing has taken place in permafrost masses accompanied by the melting of ground ice. The shape of the alas is nearly round and the diameter of Lake Surdakh is about 4 km. The lake is surrounded from all sides by a larch forest. The height of the basin cliffs is about 20 m. At some places along the cliffs underground ices are exposed. The top of the ices is 1.5 m below the top of the cliffs and the ices sink into the ground in a wedge-like shape. Field observations were made as to the exposed ice, the soil around the exposed ice and the forest above the ground.
(2) Alaska and North Canada
The group was divided into three sub-groups according to their research subjects :
(i) frozen ground (ii) vegetation and (iii) soil invertebrates.
(i) Frozen ground Drilling programmes were carried out at the following locations by using a portable boring machine : three spots on polygons at Barrow ; one in a Polygon and four at Ibyuk Pingo in Tuktoyaktuk ; two at Caribou Hill near Reindeer Depot. Core samples of 4.5 cm in diameter were taken from the surface to a depth of 140 cm for analysis of their layer structures, soil colors, densities and pH's. These samples were dried in an oven, and measurements were made as to the water contents, densities and size distributions of the soil particles contained.
Ice lumps were picked up from ice layers in an ice tunnel (Fox, Fairbanks), an ice cellar (Tuktoyaktuk village), one of the ice wedges and one of the buried ice masses which were exposed along the seacoast of Kugmallit Bay 6 km from Tuktoyaktuk village to the southwest. These ice lumps and the ice cores which were taken during the drilling were sliced and observed under the polarized light for analysis of their crystal structures. It was found that the samples of ice from the above contained air bubbles and dirts, both of which were aligned in stripes, and the texture was poly-crystalline ; the crystal sizes were several millimeters.
These ice samples which were melted there were brought back to Japan for measurement of the ratio of 18O/16O. Also a 14C analysis was done on the organic materials which were included within the core samples.
(ii) Vegetation Permafrost is an important ecological factor in the subarctic forests, and the knowledge of its relationship to a vegetation process is important for an understanding of forest ecology of northern regions. On the warm, well drained sites such as southern slopes and sides of rivers, white spruce trees or white spruce-paper birches grow, while on poorly drained sites including plateaus, flats and north-facing sites, stunted black spruce trees with moss layers of Sphagnum spp. are predominant. We observed that the depths of the active layer and drainage are of special importance in the vegetation and succession of trees on permafrost near Inuvik.
(iii) Soil invertebrates Sod samples (each 19.6 cm2× 8 cm) were taken from various habitats. Soil invertebrates were picked up from the samples. The total number of soil invertebrates which were picked up at Ibyuk Pingo was 1974, of which 81.6% was found in the layer of 0-2 cm in depth, 15.1% 2-5 cm and 3.3% 5-8 cm. The composition of soil fauna and their individual numbers were as follows : Collembola : 743, Nematoda : 548 ; Acarina : 469 ; Chironomidae : 22 ; Enchytraeidae : 11 ; Tardigrada : 1 ; Trichoptera 1.抄録全体を表示PDF形式でダウンロード (3701K) -
田上 善夫1976 年 85 巻 1 号 p. 28-42
発行日: 1976/02/25
公開日: 2009/11/12
ジャーナル フリーIn the mountain district wind-shaped trees constitute typical climatic landscapes and they are regarded as effective indicators of the winds. But, there are some disagreements between the theories of their origin. The author attempts to clarify what agencies act on wind-shaped trees.
Some investigations are made in Rishirito-island which has an isolated mountain in the Hokkaido district and following facts are found. (A) The distribution of wind-shaped deciduous broad-leaved trees, birches and alders etc., suggests that southwesterly winds blow toward the mountain and become separate to its both sides (fig. 2). On the other hand, the distribution of wind-shaped evergreen conifers, white and silver fir, suggests that winds diverge, and also blow into the coast and blow down on the mountainside (fig. 3). (B) On the Sea of Okhotsk temperature inversions in the lower layer often appear in Spring and Summer, and they affect the distribution of winds in Rishiritoisland significantly. In the period of stable stratification (May-August), generally, southwesterly winds that blow against the mountain, diverge to its northwestern and southeastern side. And the winds stagnate in the windward, blow through the both sides, and blow gently in the leeward. While in the period of unstable stratification (October-March), generally, the westerly strong winds blow on anywhere but the leeward (fig. 5).
Then, examining characteristics of the distributions of winds that agree with the distributions of wind-shaped trees, the author concludes that wind-shaped trees in Rishirito-island are formed in the following way. In the case of deciduous broad-leaved trees, they are deformed by the southwesterly winds that prevail in the period of stable stratification. In the case of evergreen conifers, they are deformed by the same southwesterly winds as in the former case, and in the limited area they are deformed by the salt breezes that prevail in the period of unstable stratification. Hereafter it is essential to find out another agency that forms wind-shaped trees.抄録全体を表示PDF形式でダウンロード (2422K) -
坂本 峻雄1976 年 85 巻 1 号 p. 43-60
発行日: 1976/02/25
公開日: 2009/11/12
ジャーナル フリーThe work of the Compilation Committee was inaugurated early in 1950 under the auspices of the Tokyo Geographical Society. The work which has continued for 25 years was recently completed in June 1975. The data for the compilation were contributed by the geologists who had been engaged personally in investigations in geology and mineral resources on the Continent and Taiwan, before the end of the war. The number of contributors reached about 200.
The main books and maps published by the Committee are itemized below :
Geology and Mineral Resources of the Far East (in Japanese)
60 sets Vols. 1, 2 & 3 1991 p 1952 ;
Geologic Maps of the Far East, 1/250, 000 (in English)
196 sets 127 sheets/set 1954-1960 ;
Geology and Mineral Resources of the Far East (in English)
600 sets Vols. 1, 2 & 3 1385 p 1967-1971.
In April 1975, a total of 391 volumes of the Geology and Mineral Resources of the Far East were mailed to 274 universities and organizations in 86 different countries of the world, as a gift from the Committee. 140 have reported and acknowledged the receipt of the gift.
We very sincerely acknowledge the assistance accorded the Committee throughout the years by different institutions such as the Ministry of Education, the various universities, the National Science Museum, Geological Surveys both of Japan and the United States of America, and the University of Tokyo Press. The U.S. Geological Survey, through their former Tokyo Branch, very generously helped the Committee, especially in color printing the geologic sheet maps.
In accomplishing the Committee's work for distribution of the above publications, we hereby cordially thank again all the institutions which helped promote the project as well as all of the collaborators for their contribution of unpublished materials for compilation.
Tsutomu Ogura, Sendai
Chairman of the Committee
October, 1975抄録全体を表示PDF形式でダウンロード (2359K) -
矢沢 大二1976 年 85 巻 1 号 p. 61
発行日: 1976/02/25
公開日: 2009/11/12
ジャーナル フリーPDF形式でダウンロード (165K) -
式 正英1976 年 85 巻 1 号 p. 61a-63
発行日: 1976/02/25
公開日: 2009/11/12
ジャーナル フリーPDF形式でダウンロード (542K) -
木下 誠一1976 年 85 巻 1 号 p. Plate1-Plate2
発行日: 1976/02/25
公開日: 2009/11/12
ジャーナル フリーPDF形式でダウンロード (2369K)
- |<
- <
- 1
- >
- >|