ギリシャにおける山地荒廃と土壌の受食性について

抄録

At present, there are many devastated mountains in Greece. Soil loss from this area is a serious problem in terms of national land safeguard. Under such a condition, dams are being established in some places in order to meet the increasing demand of water and to control flood. However, it is pointed out that there is a dangerous possibility that the dams may be stuck with much eroded soil running from upper part of stream. We, together with cooperating researches of Aristoteles University and Ministry of Agriculture Forest Research Insitute in Greece, are continuing our study so as to clarify the causes of mountain devastation and establish the measures for devastation prevention. In 1984, we started our research with the help of Japan Society for Promotion of Science and plan to finish it within two or three years.
This report is based on the first field survey held in Oct. 1984 and is a summary of overall view of devastated mountain and results of measurement on infiltration capacity and analyzing of some soil erodibilities in ten survey areas. In each survey area of different cover condition, infiltration capacity was measured by the simple inf iltrometer of tube type and soil . hardness by Yamanka's penetrometer under the naturally undisturbed condition. We analyzed some other erodibilities such as erosion ratio and dispersion ratio of the sampling soils in 0-5cm depth. These erodibility indexes are higher especially on bare land where goats are trampling and in man-made pine forest (Pinus halepensis Miller etc.) than in naturaloak (Quercus: pubescens Willd etc.) and fir (Abies cephalonica Loundon etc.).
In the survey of this time. we could not clarify the followings; relation to causes and effects of mountain devastation phenomenon, confirmation of changing process on devastation condition and grasping of exact sediment yield from denuded area. Therefore, we are planning to survey these three points neyt time.