著者

益田 晴恵

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.131, no.6, pp.573-584, 2022-12-25 (Released:2023-01-12)

参考文献数

58

被引用文献数

2

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The history of hot spring studies and research in Japan is reviewed mainly from the viewpoint of Earth science. Studies on the geochemistry of hot spring waters started with geochemical analyses of hot spring water in the 1830s. The relationships between the issuing mechanisms of hot springs and volcanism, active faults, and earthquakes have been studied since around 1910. These studies reveal sources and recycling paths of waters and dissolved materials in the Earth's crust and the upper mantle in relation to plate tectonics and subsequent volcanism. Microbiological studies on living organisms, such as algae, bacteria, and archaea, living in hot springs, began in the late 1880s, and have contributed to documenting the origins and evolution of life. Combined with mineralogical studies, minor and trace element analyses of hot spring water have contributed to an understanding of the formation mechanisms of ore deposits. Studies on hot spring waters triggered an understanding of the essential role of water in the Earth and its evolution.

著者

磯崎 行雄 丸山 茂徳 中間 隆晃 山本 伸次 柳井 修一

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.120, no.1, pp.65-99, 2011-02-25 (Released:2011-05-20)

参考文献数

80

被引用文献数

32 47

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The ca. 700 million year-long geotectonic history of the Japanese Islands comprises three distinct intervals; i.e., (1) the age of a passive continental margin off the South China continental margin (ca. 700-520 Ma), (2) the age of an active margin characterized by an arc-trench system (ca. 520-20 Ma), and (3) the age of an island arc off East Asia (20 Ma to the present). These three intervals are chronologically separated by two major boundaries with significant tectonic episodes; i.e., the ca. 520 Ma tectonic inversion from a passive to an active margin by the initiation of subduction from the Pacific side, and the ca. 20 Ma tectonic isolation of the modern island arc system from the Asian margin by the back-arc basin (Japan Sea) opening. Here, the evolutionary history of the Japanese Islands is revised significantly on the basis of new lines of information that derived from a new dating technique of detrital zircon in sandstone. Particularly noteworthy is the recognition of the Early Paleozoic to Middle Mesozoic arc batholiths that were exposed extensively in the past but not at all at present because the pre-Cretaceous granites merely occur as kilometer-size blocks in the modern Japanese Islands. As to these older granites, the remarkable disagreement between the current distribution and the predominance of their clastic grains in younger sandstones suggests the effectiveness of past tectonic erosion processes in the fore-arc domains. The newly documented historical change in sandstone provenance suggests that proto-Japan has experienced not only accretionary growth but also large-scale tectonic erosion in multiple stages. During the ca. 500 million-year history of the Japanese Islands, a large amount of juvenile arc (continental) crust was formed several times, however, most has already disappeared from the Earth's surface. In short, the orogenic growth of Japan, even in a long-lasting active continental margin setting, is explained as the intermittent repetition of ocean-ward continental growth and continent-ward contraction of an active arc-trench system. In contrast to these arc batholiths, the terrigenous flux from the neighboring two major continental blocks (South and North China) was less significant than previously imagined, except for the Jurassic to Early Cretaceous time when the collisional suture between North and South China blocks was selectively eroded to produce abundant terrigenous clastics. It is also significant that the eastern extension of this collisional suture was recognized in Japan as a chain of fragmentary remnants of the Triassic medium-pressure metamorphic belt. On the basis of these new lines of information, the South China-related origin of the main part of Japan is confirmed, whereas the Hida and Oki belts along the Japan Sea are identified as detached fragments of North China block. Summarizing all of these results, a series of revised paleogeographic maps of Japan from the Late Neoproterozoic to the Miocene is illustrated.

著者

青山 千春 松本 良

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.118, no.1, pp.156-174, 2009-02-25 (Released:2010-04-05)

参考文献数

28

被引用文献数

9 15

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During methane hydrate exploration and research, remote and on-board acoustic surveying and monitoring of methane hydrate can be easily and economically conducted using a quantitative echo sounder. Simultaneously, the structure and the floating-up speed of methane plumes can be obtained from an analysis of acoustic data. We conducted a survey of methane plumes from 2004 through 2008 at a spur situated southwest off the coast of Sado Island (tentatively called Umitaka Spur) and at the Joetsu Knoll. In 2007 and 2008, we performed experiments by releasing methane hydrate bubbles and methane hydrate, and letting them float upward. Consequently, we demonstrated that acoustical reflection from the methane plumes correlates with water temperature and depth, that the floating-up speed is constant but depends on the conditions of methane hydrate, that the discharge of methane hydrate bubbles changes, and that there is a wide scattering of materials below the seafloor where methane plumes are located. Furthermore, the amount of methane hydrate bubbles seeping was estimated by a preliminary calculation. The method will be applied not only to basic research on methane hydrate but also to assessments of the environmental impact of methane hydrate exploitation.

著者

石川 晃

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.120, no.6, pp.1026-1034, 2011-12-25 (Released:2012-03-05)

参考文献数

26

被引用文献数

2 3

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西太平洋に現存するオントンジャワ海台は,白亜紀に生じた地球史上最大規模の火成活動の産物であるが,その成因についてはいまだ不明な点が多い。海台縁辺部が水上に露出しているソロモン諸島・マライタ島には,海台形成後に生じたキンバーライト類似のマグマ活動により,海台直下に由来する多様なマントル捕獲岩が表層にもたらされており,大規模融解現象の発生機構やその起源物質を解明するための有用な情報源となる。地質温度圧力計の適用によると,各種捕獲岩の由来深度はモホ面直下(約60km)からリソスフェア最下部(約120km)に至ることがわかる。また由来深度に対応して,卓越する岩相や化学組成が系統的に変化する観察事実から,海台下リソスフェアの構造としてジュラ紀の海洋プレート直下に海台玄武岩を抽出した融け残りマントルが底付けされている様子が復元される。このことは,マライタ島に産する一部の捕獲岩はかつて地球深部に存在しており,温度・組成異常をあわせもつ「マントルプルーム」の構成物質として地表近傍へ上昇してきたことを示唆している。

著者

財城 真寿美 三上 岳彦

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.122, no.6, pp.1010-1019, 2013-12-25 (Released:2014-01-16)

参考文献数

25

被引用文献数

4 6

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Climate variations in Tokyo based on reconstructed summer temperatures since the 18th century and instrumental meteorological data from the 19th century to the present are discussed. During the Little Ice Age, especially in the 18th century, remarkably cool episodes occurred in the 1730s, 1780s and 1830s. These cool conditions could be a significant reason for severe famines that occurred during the Edo period. Around the 1840s and 1850s near the end of the Edo period, it was comparatively warm which could correspond to the end of the Little Ice Age in Japan. Although there was a low-temperature period in the 1900s, a long-term warming trend could be seen especially in winter temperatures and daily minimum temperatures throughout the 20th century. While annual precipitation has been increasing during the last 30 years, relative humidity has been decreasing. This could result from a saturated vapor pressure rise due to warming and from a loss of water bodies due to urbanization. During the last century, not only warmer conditions but also wetter conditions in summer and autumn and drier conditions in winter and spring were documented by analyzing hythergraphs.

著者

河本 大地

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.117, no.3, pp.617-636, 2008-06-25 (Released:2010-05-14)

参考文献数

45

被引用文献数

1

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The aim of this study is to examine to what extent the introduction of organic farming methods, typical post-productivism in agriculture, affects changes in plantation agriculture, the typical productivism in the Global South. A case study was conducted on the tea industry in Sri Lanka. The method was intensive interviews with key persons at the headquarters of plantation companies, management sections of tea estates, relevant organizations, and with some tea estate residents, as well as collecting relevant documents in July, August, and December, 2005. The findings are as follows. Firstly, the tea industry in Sri Lanka, particularly the plantation estate sector, has structural problems in terms of environment, economy, and social sustainability. These problems have been mainly caused by decreasing consumption of tea in industrialized countries and former policies of nationalizing Sri Lankan tea estates. Secondly, organic farming methods in tea plantation estates have been introduced mainly in disadvantaged mountainous areas, characterized by many abandoned tea areas and old tea bushes. Organic farming is an alternative strategy for developing the estates in such areas. These organic tea estates are trying to brand themselves, diversify crops, promote biodiversity, conduct eco-tours of estates, enhance social welfare system for residents, and introduce fair-trade certifications, as well as obtain organic certifications. Thus, organic farming in the tea estates can be understood as a strategy of diversified management, which is a combination of the elements of post-productivism. However, the cost of production (COP) is higher in organic tea estates than in conventional estates, especially the cost of composting and weeding. Due to their labor-intensive character, organic estates are affected enormously by increasing labor costs, and in the near future the outflow of labor might also be a problem. These issues are common in the Sri Lankan tea industry. Moreover, marketing to acquire new consumers in industrialized countries is not easy for organic estates, and the bought price is not increasing. This trend will not lead to the establishment of more organic tea estates. Some existing organic estates are also on the verge of closure under these circumstances. To ensure the sustainability of organic tea estates, it is necessary to expand their social welfare policies especially for younger residents, and communicate these efforts to society along with environmental conservation policies. Moreover, consumers in industrialized countries need to understand and support the challenges affecting disadvantaged estates.

著者

下司 信夫

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.118, no.6, pp.1254-1260, 2009-12-25 (Released:2010-03-23)

参考文献数

10

被引用文献数

11 14

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A large pyroclastic eruption occurred around 7.3 ka from the Kikai caldera about 30 km north of Yakushima Island. Its pyroclastic flow and fall deposits covered the entire area of Yakushima Island and may have influenced the evolution of unique floras and faunas of Yakushima Island. Detailed field survey revealed that the Koya pyroclastic flow deposit spread from NW to SE, covering almost the entire area of Yakushima. A part of the southern coastal area remained from the pyroclastic flow due to local alignment of topographic ridges and valleys, which acted as barriers to the pyroclastic flows. Possible tsunami deposits associated with the Kikai-Akahoya eruption were discovered in the area below ca. 50 m above sea level along the northern coasts of Yakushima and Kuchinoerabujima Islands.

著者

長谷川 昭 中島 淳一 内田 直希 弘瀬 冬樹 北 佐枝子 松澤 暢

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.119, no.2, pp.190-204, 2010-04-25 (Released:2010-07-06)

参考文献数

44

被引用文献数

13 10

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A dense nationwide seismic network recently constructed in Japan has been yielding large volumes of high-quality data that have made it possible to investigate the seismic structure in the Japanese subduction zone with unprecedented resolution. We introduce a precise configuration of the Philippine Sea and Pacific plates subducting beneath the Japanese Islands, which was recently obtained by seismic tomographic imaging, precise earthquake hypocenter determinations, and focal mechanism studies. Seismic tomographic studies show that the Philippine Sea plate subducting beneath southwest Japan is continuous throughout the entire region, from Kanto to Kyushu, without disruption or splitting even beneath the area north of the Izu Peninsula. The estimated geometry of the subducted Pacific and Philippine Sea slabs shows a broad contact zone between the two slabs located directly beneath the Kanto plain. It further shows the wavy configuration of the Philippine Sea slab subducting beneath the entire region of southwestern Japan. Contact between the Philippine Sea plate and the Pacific plate causes anomalously deep interplate and intraslab earthquake activity in Kanto. Moreover, the interplate coupling coefficient estimated from repeating earthquake data shows a distinct change across the northeastern edge of this slab contact zone, suggesting that the overlying plate controls large-scale interplate coupling. High-resolution studies of spatial variations of intraslab seismicity and the seismic velocity structure of the slab crust strongly support the dehydration embrittlement hypothesis for the generation of intraslab earthquakes.

著者

河江 肖剰 亀井 宏行

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.120, no.5, pp.864-868, 2011-10-25 (Released:2012-01-17)

参考文献数

7

被引用文献数

1 1

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三大ピラミッドが建つギザ台地はおもに新生代始新世時代に遡るモカッタム累層と呼ばれる浅海成石灰岩の岩盤からなっている。古代の巨石建造プロジェクトにおける最優先事項の一つは採石場の選択であるが,この累層の石灰岩は硬い層と柔らかい層の交互層からなるため採石に適していた。古代人は柔らかい層を除去し,硬い層からピラミッドや神殿建設のための巨大な岩塊を採石した。 2,590,000立方メートルの石材からなるクフ王の大ピラミッドの採石場は,南約300メートルに近在しており,そこから約276,000立方メートルの石灰岩が切り出されたと概算されている。第2ピラミッドの造営者カフラー王もギザの地形を考慮しながら自らのピラミッド複合体の建造を推進し,プロジェクト最後にはモカッタム累層の岩盤を生かし,スフィンクスを巨大な彫像としてつくりあげた。王家最後の巨石建造物は,ケントカウエスと呼ばれる女王が建てさせた彼女の2段式の墓で,独特な形をもつ。墓はもともとクフ王の石切場の中央に,おそらく石材量を量るために,残されていた岩塊だった。三大ピラミッド建造後の限られた空間のなか,彼女は使用可能な最後の土地を巧みに利用し自らの墓を建てさせた。これによってギザ台地の巨石建造プロジェクトは終焉を迎えた。

著者

吉山 昭 柳田 誠

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.104, no.6, pp.809-826, 1995-12-10 (Released:2009-11-12)

参考文献数

63

被引用文献数

20 27 36

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In this paper the new methodology for quantitative estimation of uplift rates at inland region was discussed using fluvial terrace surfaces and deposit bases. Previous studies have revealed that river profiles regularly changed according to the cyclic fluctuation of climate and sealevel ; therefore, in the interglacial ages (the marine isotope stage 5e and the present) similar profiles with large concavity formed, and in the glacial ages (stage 6 and 2) linear profiles appeared on the contrary. In upper reaches of rivers, stage 5e valley bottoms were filled with the deposit accumulated in the subsequent glacial stages. Based on these observations, the value of relative height between the stage 5e burned valley bottom and the present river floor (BV value) is considered to indicate uplift during those stages (120-130 ky). Similarly, the value of relative height between the stage 6 terrace and the stage 2 terrace (TT value) can be used as an indicator of uplift during the period between those two stages.The BV values and TT values distributed along Japanese major rivers were reviewed on the basis of previous studies on terrace development and tephro-chronology. In middle reaches of most of rivers, the TT and BV values at the same sites are concordant to each other. The BV values remarkably decrease upstream in spite of no reduction of the TT values in the upper reaches or branches. This implies that present river profiles have not completely been in equilibrium and are now degrading in the upper streams and branches. As an indicator of long-term uplift rate, the TT values have the advantage of applicability to upper reaches and availability of field data in comparison to the BV value. However, it is impossible to apply these methods in the upper reaches or branches where fluvial terraces are not well developed.Up until now, the uplift rates in mountainous region were presumed from the outlined altitude of mountains or the amount of eroded material trapped in reservoirs, but have not been examined by direct data. The uplift rates obtained by using TT values and BV values are 0.10.8 mm/year in large number of sites, which are not located in very high mountainous area. Large uplift rates more than 1 mm/year were estimated from TT values at the Kurobe river basin, in the northern part of Chubu mountainous region.

著者

古谷野 裕 早川 由紀夫 町田 洋

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.105, no.4, pp.475-484, 1996-08-25 (Released:2009-11-12)

参考文献数

12

被引用文献数

4

著者

大森 房吉

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.19, no.4, pp.251-257_1, 1907-04-15 (Released:2010-10-13)

著者

磯崎 行雄 丸山 茂徳

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.100, no.5, pp.697-761, 1991-10-25 (Released:2010-10-13)

参考文献数

195

被引用文献数

186 206

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The Japanese Islands consist fundamentally of late Paleozoic to Cenozoic accretionary complexes that formed in situ in a subduction zone along the East Asian continental margin, i.e. 2.0 Ga Yangtze craton (South China) and 450 Ma fore-arc ophiolite. Recent research utilizing microfossil and radiometric dating has distinguished several major accretionary complexes, including high-P/T metamorphosed parts, and subordinate ophiolites. In particular, recognition of oceanic plate stratigraphy and age of subduction-related metamorphism for individual accretionary complex allows the geotectonic subdivision of the Japanese Islands be emended with a new definition of geotectonic units and their mutual boundaries. Removing the effect of arcrelated magmatism and secondary tectonic modification by microplate activities such as backarc basin opening, fore-arc sliver movement, and arc-collision, a remarkable oceanward younging polarity is recognized among the accretionary complexes. This polarity in growth is well observed in Southwest Japan where seven distinct units occur, i.e. from the Japan Sea side to the Pacific side: 400-300 Ma high-P/T schists, Permian (250 Ma) accretionary complex, 230-180 Ma high-P/T schists, Jurassic (180-140 Ma) accretionary complex, 100 Ma high-P/T schists, Late Cretaceous (80 Ma) accretionary complex, and Tertiary (50-20 Ma) accretionary complex. The sinuous surface trajectories of these geotectonic boundaries and occurrence of several tectonic outliers and windows indicate that all these complexes, including high-P/T schists, occur as subhorizontal (or gently northward dipping) thin tectonic unit, i. e. nappe. Thus the Japanese Islands form a huge pile of nappes that become younger structurally downward to the modern Nankai accretionary complex. What is remarkable in this subhorizontal orogen is that high-P/T units are tectonically intercalated between low-P units, e. g. the thin nappe of 100 Ma Sanbagawa blueschists between Jurassic and Late Cretaceous accretionary complexes of the prehnite-pumpellyite facies. Uplift of the Sanbagawa high-P/T unit appears to correlate with the arrival of the Kula/Pacific spreading ridge at the trench, suggesting that this high-P/T accretionary complex may have been extruded and uplifted into low-P domain in fore-arc by buoyant subduction of the spreading ridge at the trench. Evidence of ridge subduction at that time is supported by reconstructed paleoplate motion and the coeval climax of arc-related Ry-oke magmatism associated with low-P/T regional metamorphism. Formation of older high-P/T blueschist nappes sandwiched between low-P units can be explained likewise. Subduction of major spreading ridges seems most critical for the episodic oceanward development not only of subhorizontal high-P/T nappes but also of continent side granitic belts.

著者

石橋 克彦

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.102, no.4, pp.341-353, 1993-08-25 (Released:2010-11-18)

参考文献数

52

被引用文献数

4 5 5

著者

本井 達夫 鬼頭 昭雄 緑川 貴 荒川 理 笹井 義一 陳 永利

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.117, no.6, pp.1015-1028, 2008-12-25 (Released:2010-04-26)

参考文献数

43

被引用文献数

1 1

---

Climate model experiments are carried out to understand the relationship between large-scale topography and climate variation. Mountain uplift experiments show that sea surface temperature, surface wind fields, precipitation and sea surface salinity are strongly influenced by mountain uplift. An enhanced Asian monsoon due to mountain uplift causes stronger seasonal coastal upwelling in the Indian Ocean and freshening in the Bay of Bengal, Yellow Sea and East China Sea. Mountain uplift experiments using a higher resolution atmospheric general circulation model reveal that the spatial pattern of precipitation becomes finer as resolution increases, and that there is a sharper contrast in the salinity distribution near coastal regions. Experiments in which the Panamanian Gateway is closed, opened and re-closed suggest that reorganization of the ocean current due to closure of the Panamanian Gateway induces a cooler and drier climate with a permanent halocline and sea ice in the subarctic Pacific.

著者

吉田 英嗣

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.119, no.3, pp.568-578, 2010-06-25 (Released:2010-08-30)

参考文献数

112

被引用文献数

2 2

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The Japanese Islands are tectonically active and humid. Thus, erosion and deposition are the primary processes controlling geomorphic development. Catastrophic sector collapses at volcanoes should be considered significant in this context. This study examines the geomorphological role of volcanic sector collapses in Japan, introducing 58 cases with their respective occurrence ages and volumes (≥ 1×108 m3). We find that the frequency of sector collapses becomes exponentially higher as the collapse magnitude decreases. The total volume of the dissected volcanic edifice caused by catastrophic collapses amounts to ca. 6.4 km3 (640×108 m3) during the last 500 years. This value can be translated into an annual denudation rate of 0.53 mm/y per unit area of the Quaternary volcanoes (ca. 24000 km2), which is comparable to the contemporary denudation rate of non-volcanic mountains in Japan. Therefore, although volcanic sector collapses occur intermittently, we have to consider them as sediment sources that are indispensable to an understanding of geomorphology in Japan.

著者

木村 政昭 笠原 順三 麻植 誠二郎

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.91, no.4, pp.217-238, 1982-08-25 (Released:2009-11-12)

参考文献数

22

---

Spatial and temporal relations between large interplate earthquakes and eruptive activities along Northeast Japan was studied by means of a two-dimensional model using the finite element method. Stress fields were calculated using seismological data in Northeast Japan. The stress value for each earthquake was normalized by using the seismic moment Mo instead of earthquake magnitude M. Stress differences before and after great earthquakes show close relationships with eruptive activities in Northeast Japan. The results suggest that eruptive activities increase under the increased compressive strain of pre-seismic conditions and their activities abruptly decrease under post-seismic conditions.

著者

諏訪 彰

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.64, no.4, pp.169-172, 1955-12-30 (Released:2009-11-12)

著者

田口 洋美

出版者

Tokyo Geographical Society

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.113, no.2, pp.191-202, 2004-04-25 (Released:2009-11-12)

参考文献数

60

被引用文献数

2 1

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It is generally assumed that the Japanese society and culture have been developed on the basis of the agriculture, especially on the rice field cultivation. Hunting, therefore, has been considered a sub-culture insignificant in the socio-cultural context as a whole. The author, however, is of the opinion that the two activities, agriculture and hunting, which are seemingly unrelated in outlook, have been strongly linked and have played complementary roles to each other.Japanese traditional hunters, Matagi, played an important role here as semi-professional hunters, and their hunting has increasingly become market-oriented.Agricultural activities inevitably destroy the natural habitat of wildlife by reclaiming or clearing forests to make the land suitable for cultivation, thus eliminating wild animals. Ironically, however, crops grown on cultivated land, which are rich in nutrition, attract wild animals. If the farmers intend to keep high productivity, those animals must be efficiently expelled from the man-controlled area. Agriculture is simply incompatible with wild animals.Hunting for a living, on the other hand, in essentially to capture wild animals, they are either consumed as various resources by the hunter himself or sold or exchanged for the necessities of life. To ensure sustainable hunting, the number of wild animals must also be sustained, which means the number of captures and the reproduction of animals must be well balanced. Hunting activities thus inevitably require coexistence with wildlife.Hunting and the agriculture, contradiction in principle, however, could and actually have cooperated to form a complementary relationship, which could be called a system : the hunters eliminated wild animals from cultivated land, and the crops attracted game animals for hunting. Around the peripheries of cultivated areas such complementary relationships have been and still are sustained.Historically, such relationships were gradually established from 17th to 18th centuries, when the Edo Shogunate encouraged as its policy to expand agricultural lands. With the technological advances of irrigation systems, marshlands and shoals were turned into rice fields in the plains, and hills and valleys were cultivated in the mountain regions. Hunting then gradually became involved in the agricultural activities to protect farmland from wild animals.In the later period of the Edo Shogunate, the farmers themselves began to capture or chase wild animals out of farmland. At the same time, some hunters with highly professional hunting techniques began further chasing and hunting game animals beyond the cultivated lands. Villages experiencing greater damage from wild animals often hired such hunters. The resources obtained from the captured animals and birds, such as furs, hides, feathers, tendons, meat, and internal organs and bones for medical use, were supplied to the local markets. Hunting thus found its niche at the peripheries of agriculture and the market that demanded animal resources, though limited in quantities and in the number of consumers the market might have been.The flow of animal resources, from agricultural land, to the hunters, then to the market, seems to have been established as a system around 18th to 19th centuries, as the monetary system began to prevail and currency was widely used.As Japan turned into the Modern Ages, hunting became more market-oriented and also strictly controlled : hunting was encouraged to supply furs for export to Europe and the US, and for the military use under the Imperial militaristic government at the time.A historical review of hunting in Japan suggests that, as for the conservation of wildlife, a historical and socio-cultural viewpoint is essential along with ecological and ethological research.

著者

鈴木 力英

出版者

公益社団法人 東京地学協会

雑誌

地学雑誌 (ISSN:0022135X)

巻号頁・発行日

vol.119, no.3, pp.556-561, 2010-06-25 (Released:2010-08-30)

参考文献数

10

被引用文献数

1 1

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In mid-November, 2009, a breach of the server of the Climatic Research Unit (CRU) of the University of East Anglia, UK, occurred, and more than 1,000 e-mails were copied and disseminated over the Internet. CRU is one of the leading climatology institutes, and has constructed a long-term world temperature database that was referenced in the assessment report of the Intergovernmental Panel on Climate Change (IPCC) as evidence of global warming. The words “trick” and “hide the decline” in an e-mail, which mentioned the process for preparing the temperature time series, generated the allegation; those words demonstrated that scientists at CRU intended to falsify data to exaggerate warming. However, it can be regarded that the allegation was a manufactured controversy originating from irrelevant interpretations of personal e-mails at CRU. Scientists are now being requested to ensure that scientific knowledge and understanding are convincing not only to scientists but also to the general public.