In order to clarify the actual conditions of satoyama (rural forests) and the fundamental problems concerning their management, current studies on satoyama in ecology, phytosociology, forestry, landscape, recreation, amenity, environmental education etc. are reviewed and discussed. Satoyama is classified into four secondary forest types, lucidophyllous, screllophyllous, summergreen and pine dominated. Summergreen secondary forests have developed in the Kanto area, pine dominated secondary forests have developed in Setouchi area and lucidophyllous secondary forests have developed in Shikoku, Kyushu etc. along the Pacific coast of the Japanese archipelago. Summergreen, lucidophyllous and screllophyllous secondary forests are regenerated by sprouting and these coppice forests have not been managed due to the decline in the need for firewood and charcoal. Therefore, satoyama is being damaged by climbers, bamboos and pine wilt disease on the one hand,and is undergoing the succession from elfin forest to tall summergreen or lucidophyllous forest on the other hand. In order to maintain the traditional landscape, species diversity and fields for recreation, we should manage satoyama by new methods as an environmental forest having public functions. We introduce a few projects in which satoyama is being managed.

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Many fossils of marine reptiles have recently been found in the Upper Cretaceous system of the Japanese Islands. An isolated tooth was found in the Lower Maastrichtian section of the Izumi Group in Awaji island, Southwestern Japan. The tooth shows characteristics of Plesiosauroidea. This is the first Plesiosauroid from the Izumi Group, and this paper contains the first description of Plesiosauroidea from the Maastrichtian section of the Japanese Islands.

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A typical fan-shaped delta has developed at the mouth of the Chikusa River in the Ako Plain, in Hyogo Prefecture, western Japan. In this study, we discuss the sedimentary environment of the deltaic deposits layed during the Holocene bv means of analyses of three boring-core sediments(bc-1, BC-2, and HBC-1). The chronology of the core sediments is based on the ages of intercalated volcanic ashes and on AMS-14C dates for wood fragments and shells contained in the core samples. This is used to estimate the sedimentation rate of the deltaic deposits. Analyses of sedimentary sulfur and diatom assemblages in the samples provide the information of the changes in the sedimentary environment caused mainly by Holocene sea-lev el changes. The results are as follows: 1) At ca.8,000 yrs BP, the coast line had reached BC-2 site in the central part of the present delta by the Holocene transgression. After the culmination of this transgression, a small regression occurred at ca.3,000 yrs BP. This was f oi lowed by another small transgression. 2) At BC-2 site, the constant sedimentation rate of the deltaic deposits had occurred during the period of ca.8,000-230 yrs BP, suggesting that the sediment supply from the Chikusa River had been almost constant during this time. On the contrary, at HBC-1 site in a small drowned valley where the river is not important as a sediment source, sedimentation rate over the last 4,800 years was estimated to be nearly one-fourth of that during the period of ca.6,300-4,800 yrs BP.

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We analyze grain-size distributions, types of minerals and rock fragments, and contents of magnetic grains (weight percentages of magnetic grains smaller than 2mm in diameter) on a boring-core sediment in the lowest area of the Chikusa River, Hyogo Prefecture, Western Japan. For comparison with the core sediment, we carried out the same analyses on the present surf ace deposit at a tideland off the river mouth.

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Rearing cattle in the Tajima area of Hyogo prefecture, western Japan, is closely connected with rice cultivation in terraced fields .This paper describes how the farmers recognize and utiliz ethe mountainous environment in rearing-cattle, with special reference to the farmers' knowledge regarding the wild grasses which constitute the major fodder of the cattle. Farmers utilize as much straw and wild grasses as possible, which are produced in the terraced fields ,especially wild grasses growing on the slopes and ridges between the rice fields .Farmers also obtain fodder from non-cattle-rearing farmers, so that the area of terraced rice-fields as a whole supports cat tie-rearing. The food preference test carried out on cattle revealed that farmers have precise knowledge concerning the cattle's preference among wild grasses. Especially, mixtures of several wild grass species are highly valued by the farmers as cattle fodder, and the cattle actually show high preference for these mixtures.

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Kobe and cities surrounding it were heavily damaged by the 1995 South Hyogo Earthquake which occurred at Jan. 17th. In order to clarify the usage and the damage of open spaces within the area under such a situation, a survey was carried out by Japanese Institute of Landscape Architects (JILA), approximately within the 3rd and 4th week following the Earthquake. The author surveyed mainly public parks in Hyogo, Nagata and Suma ward in Kobe City as a member of JILA with other stuffs at Museum of nature & Human Activities ,and compiled the data. JILA already reported the summerized results. However, the raw data and detailed results were not described in the report. The purposes of this paper are to publish a regionally limited part of the results from the survey and to discuss the clarified problems ragarding the safety of the area. Through the discussion, following points were induced. 1. Huge stone-made monuments and elevated highways were the most dangerous public facilities around open spaces in the area. To maintain safety from monuments, enclosure by fences or hedges may be effective. 2. 51% of the surveyed open spaces were used as camp sites by refugees. These can be classified into 3 types, i.e., 1)Dense and well-ordered type, relatively well supported by governmental sectors and containing many tents from the Japan Self Defense Force, 2) Sparse, however, a collective type, formed by groups of tents, occasionally organized by a self-governmental community, and, 3)Not a collectiv eone, almost no organization and not supported. Some refugees selected the camp site according to their own necessity for privacy or other reasons. Uniform organization or support may eliminate such chances of selection. 3. Public parks enclosed with solid fences (e.g .steel-pip efences) may lose accessibilit yF.or one must remove the fence to enter or to leave there when the access is filled with rubble, hence, the fencing materials must be chosen carefully. 4. The usage of public parks is statisticall yrelated to the existance of local faciliti e(se.g. community halls ,schools, local governmental facilities..etc.).Howev esruggestive the fact seems, more detailed research andsurveys are needed for designing the relationship between open spaces and such facilities.

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The field occurrence and petrography of late Cretaceous to early Paleogene plutonic rocks throughout Hyogo Prefecture are reported. Based on petrography, these plutonic rocks can be classified into six zones in an east-west direction.

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Petrographical data, K-Ar ages, thermoremanent magnetizations and major chemical compositions of late Neogene to Quaternary volcanic rocks have been collected in the northern part of the Hyogo prefecture. On the basis of K-Ar ages, these volcanic rocks are classified into Pliocene volcanic rocks(3.4~2.4Ma) and Pleistocene volcanic rocks(1.7~0.3Ma). The Pliocene volcanic rocks are represented by the Teragi group, Hachibuse and Hyonosen volcanic rocks composed mainly of voluminous calc-alkali andesite and subordinate monogenetic volcanoes of alkali basalt. The Pleistocene volcanic rocks are sporadically distributed throughout almost all the area. They generally form the small monogenetic volcanoes composed of alkali basalts, but the Oginosen volcano is exceptionally large in scale and made up of alkali basalt and calc-alkali andesite. Data of thermoremanent magnetization show that most of the volcanic rocks have normal-remnant magnetization but the Genbudo lava has a reverse-remnant magnetization corresponding to the Matuyama reversed chron. Major chemical compositions of the volcanic rocks show that the Pleistocene volcanic rocks are richer in Ti02, ai2o3, total Fe203, Na20, K20 and p2o5 and poorer in MgO and CaO than the Pliocene volcanic rocks.

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Hyogo Prefecture has been known as one of prominent prefectures for metallic and nonmetallic mineral resources in Japan. There are variety of types of (1) metallic deposits and (2) non-metallic deposits in Hyogo Prefecture as shown below: (1) metallic deposits: polymetallic (Cu ・ Zn ・ Pb) vein deposits, Zn ・ Pb skarn deposits, bedded cupriferous pyrite deposits (Kieslager deposits), Au-Ag vein deposits, Ni deposits, podiform Cr deposits, bedded Mn deposits, Mo deposits and Fe skarn deposits, and (2) non-metallic deposits: strata-bound brick-silic astone (Keiseki) deposits, talc deposits, feldspar deposits, pottery stone (Toseki) deposits, and Roseki (pyrophyllite-, kaolin-, or sericite-clay )deposits. Especially, the Ikuno and Akenobe mining region has been famous as one of the largest and significant metallogenic regions in Japan and the large-scale Sn-W-bearing polymetallic vein deposits has been mined for copper, zinc, lead and tin. In this paper, location and type of ore deposit, geological setting, host rock of ore deposit, grade and constituent minerals of ore, metallogenic period and history of mining are briefly reviewed and summarized for each metallic and non-metallic mine in Hyogo Prefecture.

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