In recent years, ayu (Plecoglossus altivelis Temminck et Schlegel) breeding has been reorganized into an industry characterized by areal differentiation. The writer investigated the reorganization of the ayu breeding area in the Nakagawa plain, Tokushima Prfecture, which has the largest ayu breeding industry in Japan. The results are as follows.
Ayu breeding in the Nakagawa plain has rapidly developed since 1964 under a strong cooperative system of quality control and sales. But ayu breeding is not uniform; it varies from one area to another with natural and social conditions.
The ayu breeding industry in the Nakagawa plain has, from its beginnings, had the areal differences of management style on the two sides of the Nakagawa river, because one has an underground water supply and the other does not. Since then, the introduction of a cooperative system of quality classification and of sales, accompanied by governmental formation of leading breeding areas, hasexpanded and strengthened the areal differences in the management system. At the same time, the introduction has made clear the differences in the distribution systems on the opposite sides of the river.
Since the first oil crisis, the ayu breeding industry has need a reduction in production cost or to cover rise of materials costs and the fall of wholesale prices for ayu. The reduction in production cost with the internal expansion has been more important. Basically ayu breeding depends on underground water conditions, which along with management techniques can make the difference between profitability and loss.
Areal differentiation of the ayu breeding industry in the Nakagawa plain has ideutified six districts: the left and right sides of the river upstream, midstream, and down stream. As factors in areal differentiation, water conditions are identified as the main factor and cooperative distribution as the secondary factor.

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This paper discusses recent studies since 1975 on the tectonic geomorphology of New Zealand, acountry which is well-known for work on this subject. The regional character of the tectonic landforms is controlled mainly by the tectonic setting of New Zealand at the boundary between the Australian (Indian) Plate to the west and the Pacific Plate to the east, with opposed subduction zones at the northeast and southwest margins and a complex zone of shear deformation linking the two. The Taupo Volcanic Zone in North Island is a volcanic arc and marginal basin characterised by volcanism and crustal extension.
Active faults and deformed marine and fluvial terraces are prominent tectonic landforms. Detailed research on the Alpine Fault are being supplemented by intensive works on active reverse faults. In South Island this includes trenching studies. The characteristics of the deformed topography and trench logs across the Dunstan Fault and Pisa Fault in the Otago area demonstrate the close similarity between reverse faulting here and many active reverse faults in Japan. The deformation of fluvial terraces and the height of postglacial transgressive deposits and marine terraces indicate a very high uplift rate in the Southern Alpes east of the Alpine Fault which is ascribed to vertical drag along the Alpine Fault due to the plate convergence.
Marine terrace studies, especially in North Island and some parts of South Island have made much progress. In North Island, the last interglacial terrace reaches a maximum height of 300m and the postglacial terrace a maximum of 27m. The deformation pattern shows regional differences. In North Island, landward tilting away from the Hikurangi Trench is observed on the eastern coast. Folding with short wavelength and small-scale block faulting dominate the central to southeast coast and the south coast. Downtilting towards the sea continued in the Taranaki area during the middle to late Quaternary. Holocene marine terraces can be used as reference surface for the reconstruction of paleoseismicity. Fourteen tectonic regions are identified on the east coast of North Island on the basis of the number of subdivided Holocene marine terraces and their radiocarbon ages. Some of offshore seismogenic faults are inferred from submarine landforms and records of obtained seismic profiling. In South Island, discussion has focused on the recognition of very high terrace remnants and on age estimation of terraces which have no datable materials and key beds for correlation.
Tectonic landforms have been used as references for compiling a Quaternary uplift map. The maximum uplift rate of 17mm/yr is located on the east side of the Alpine Fault, South Island. The highest uplift rate in North Island is 4mm/yr north of Gisborne and Turakirae Head near Wellington and was derived from Holocene marine terrace data. It is, however, still difficult to establish a temporal sequence for uplift rates because of insufficient age control.

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The beech (Fagus crenata) is a, dominant tree species of the broad-leaved deciduous forest in cool temperate regions of Japan. The northernmost area of its distribution is situated in the Kuromatsunai Lowland in the northern part of the Oshima Peninsula. This paper discusses the distribution of forest vegetation in relation to micro-environmental conditions in the Utasai National Forest, which is thelargest primeval forest in this area that includes beech stands.
In order to observe the relationships between the distribution of forest vegetation and edaphic conditions, detailed-scale landform units were established on the basis of the morphology, component materials, and stability of the land surface. For each landform unit, soil type was determined in the field and soil water content was measured in the laboratory. The forest vegetation was classified based upon the dominant species of the canopy layer, and the correlation between the distribution of the community types and edaphic conditions was examined for each landform unit.
The results obtained by the present investigation can be summarized as follows:
1. The land surface, the soil profiles, and the forest vegetation were classified into 14 landform units, five soil types including one subtype, and five community types, respectively.
2. The distribution of the five community types is related to soil moisture conditions. They are arranged in the following order, from dry to wet habitats: the Fagus crenata type which dominates on landform units with the soil type BC-BD, the Quercus mongolica var. grosseserrata type on BD-BE, the Tilia japonica type and the Acer mono type on BE-BF, and the, Ulmus davidiana var. japonica type on BF.
3. A forest stand with no beeches is found on the terrace surface I. This clear-cut segregation has presumably resulted from soil drainage conditions.

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