Through the examinations of the Hitakibara (the Matukawa river alluvial fan) of Suzaka City and the Yomase river basin (the Yomase river alluvial fan and the foot area of Mt. Kosha) of Nakano City, where a prefecture-operated dry field irrigation project was carried out in the 1960's, this study identified the difference between the two regions after clarifying regional characters, irrigation facilities and their utilization, and methods of maintenance and management. (1) Both regions are occupied by orchard for a large part. However, the process of development differs. Namely, the Hitakibara was a common meadow until the middle of the 19th century and therefore there were a few of villages in the region, and was developed by farmers who crossed the village border from surrounding villages. On the other hand, in the Yomase river basin (alluvial fan), paddy fields were developed and villages were grown because of excavation of the Hachikago canal possessing exclusive water right. (2) In both regions, water is supplied to each orchard through pipelines from pumping facilities and fixed-overhead watering systems by sprinklers are adapted. In the Hitakibara, the watering is done by operating electric valve automatically through remote control from the first pumping facility. On the other hand, the watering in the Yomase river basin was done by hand-operated valves all over the region at the beginning. Since 1986, however, the watering in some parts of the region has been done by operating electric valves automatically through control device using solar battery in the orchard. (3) As for the utilization of irrigation of facilities, it aims at watering for growing fruits in open orchard in the Hitakibara and the irrigation period is May 1st through September 30th. On the other hand, the Yomase river basin is divided into watering area operated by hand and that operated automatically by electric valves. The former aims at watering for growing fruits in open orchard. Meanwhile, the latter aims at watering for growing fruits in open orchard and some parts in plastic green houses and watering to avoid frost damage and the irrigation period is April 1st through September 30th. (4) The organization of maintenance and management of irrigation facilities is very important because of the demand for an intentional distribution of water in the dry field irrigation. In the Hitakibara, the land improvement district manages from intake facilities to terminal irrigation facilities and does watering directly, and board of maintenance and management organized by beneficiaries bears nothing but a supplementary role. On the other hand, in the Yomase river basin the land improvement district controls intake facilities, pumping facilities and main canals, and the board of maintenance and management as village communities controls branch canals and terminal irrigation facilities in the orchard and does watering. (5) The following have become clear by comparison of those characteristics mentioned adove. (1) The reason why watering to avoid frost damage in the Hitakibara is not done is that the authorized irrigation period starts from May 1st and an acquisition of irrigation water at the end of April is impossible. (2) The reason why growing of grapes (kyoho) in plastic greenhouse with heater, which can earn a lot of profits only in the upper parts of the Yomase river alluvial fan, is being done is because in this region, water for irrigation starting from February can easily obtained from the Hakkago canal. (3) The reason why the land improvement district in the Hitakibara instead of village cornmunities manages directly from intake facilities to terminal irrigation facilities and does watering are considered as follows. Firstly, an agricultural labor force necessary for management is becoming short due to increase in part-time farmers.
The results of in situ survey in the selected places in the periphery of Taklimakan Desert are described with an emphasis on the relationship between spectral reflectance and soil moisture contents. It is found that there is inverse relation between the spectral reflectance and soil moisture content, and it is found that soil moisture content can be estimated from the value of spectral reflectance. The results of in situ measurement indicate that the average reflectance of the soil in the periphery of Taklimakan is 21% in the visible spectrum, and 29% in near infrared spectrum respectively. If short wave infrared spectrum (up to 2, 500 nm) is included it rises up to 38%. It is also found that reflectance of dry soil in near and short wave infrared is nearly 10% higher than that in the visible spectrum. In Hotan area, the day time surface temperature reached as high as above 42°C in late October while below the surface, soil temperature dropped sharply reaching 20°C at 5 cm depth. Large radiation cooling was observed at night reaching as low as 2 °C at the ground surface.
In 1771, according to several trustworthy historical records, a huge tsunami named the Meiwa Tsunami washed the southern part of the Ryukyu Islands killing about 12, 000 people. The tsunami attributed probably to a large earthquake generated by a submarine thrust fault along the Ryukyu Trench. The southern Ryukyu Islands consisting of Miyako, Irabu, Shimoji, Tarama, Ishigaki, Iriomote and other small islands are fringed by coral reefs, and large Holocene coralline boulders possibly transported by past tsunamis, are extensively distributed on land and reef flats. Among these boulders, those composed of aragonite by 100% or nearly 100% are reliably dated by the radiocarbon method, and are good evidence for inundation, run-up heights and timing of tsunamis in the past. In order to infer the timing of past tsunamis, we dated samples carefully collected from the uppermost parts of these Holocene coralline boulders and fragments. Based on 65 dates, we restored a tsunami history in the area during the past several thousand years. Most of the coralline boulders we dated are much older than the age of the Meiwa Tsunami about 200 yr BP. Certain periodical distributions of the ages among the boulders suggest that the area had been attacked by huge tsunamis around 600, 1, 100, 2, 000 and 2, 400 yr BP during the last 3, 000 years. Thus tsunamis which brought tsunami boulders on land occurred repeatedly with intervals of several hundred to one thousand years in the study area. The tsunamis occurred around 1, 100, 2, 000 and 2, 400 yr BP were judged from the distribution of boulders of similar ages, that they were generated along the Ryukyu Trench while that of 600 yr BP along the Okinawa Trough. The tsunami about 2, 000 yr BP is most reliably restored among the past tsunamis in the area and is named the “Okinawa-Sakishima Tsunami”. This tsunami attacked an extensive area from Miyako to Ishigaki islands and transported many huge tsunami boulders such as “Tsunami Oishi” deep on land.
In this paper the author clarifies the sequence of land use change in the Auckland city's countryside and analyses it at micro-scale using the example of Clevedon area, Manukau City. Clevedon area is situated around the built-up area of Auckland and is everywhere zoned for rural land use. In this area definite changes agricultural land use to urban land use are not apparent, but agricultural use changes to other agricultural one in terms of function and quality. Three sequences of land use change based on competition between agricultural and urban uses and land use policy of the Manukau City Council are recognisable; before 1969, 1970 to 1983, and after 1984. In the 1970s and early 1980s a trend from dairy farming to beef farming and from sheep and beef farming to more specialised beef farming was apparent in the framework of traditional pastral farming. Dairy farming remained important during this period with changing ownership of land and changing location of town milk production but the less labour intensive beef farming became attractive with decreasing agricultural labour force. New Zealand pastoral farming permits such changes in livestock specialisation as the system is very flexible and not capital intensive. In fact these trends could be reversed with fluctuations of milk and meat price. In the 1980s land use change was characterised by various farms of horse raising and horticulture, and in some areas traditional pastoral uses, occupying former dairy and cattle farms. These changes had not been evident in the previous period, and the rural land use zoning encouraged them, but the trend to horse raising and horticulture became stronger in this period. The grazing of horses was associated with the purchase of rural land by other farmers and with the growing importance of the commercial blood stock and racing industry in South Auckland. The horticulture based on using labour, land and capital more intensively, and it is developed in Rural Two zone where fruit growing have priority. Availability of small parcels of land in the rural zone originating in previous periods, increasing property taxes as land values increased, and much demand for high profitability of rural land, contributed to the changes in the function of agricultural land use. In the 1980s the sequence of agricultural land use change is uni-directional. Reversion to the traditional pastoral farming of the area is not an option. Thus, in comparison with the earlier period a feedback sequence is not included in model.