新潟県糸魚川市東部には第四紀更新世の火山岩類が広く分布しており，下位より猿倉層（新称），江星山層，梶屋敷層，高峰層（新称）からなる．下部更新統の猿倉層は安山岩–玄武岩質安山岩の火山砕屑岩からなる．江星山層はデイサイト–玄武岩質安山岩の火山砕屑岩，貫入岩からなり，およそ1.3–1.2 MaのK–Ar年代を示す．岩石学的性質及びK–Ar年代は西頸城半深成岩類の鉾ヶ岳岩体と共通する．梶屋敷層は高峰層と同質な火山岩礫を多く含む堆積岩で，挟在する大谷川凝灰岩はおよそ1 Maのフィッション・トラック年代を示す．高峰層は梶屋敷層と一部指交関係で上位に位置し，安山岩–玄武岩質安山岩の火山砕屑岩からなる．上部の凝灰角礫岩本質岩塊のK–Ar年代は0.65 Maであり，高峰層の火山活動は少なくとも1 Maから0.65 Maの期間にわたる．火山岩の全岩化学組成から江星山層は特徴的に中カリウム系列の低カリウム側の組成領域にあり，他の層とは区別される．

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I studied the distribution of villages and the interactions between people and forests in a lowland plains of Sumatra. I classified the villages there into four types. Pangkalan villages (river ports at the foot of hills) are located in flood zones. Muara villages (river ports at confluence points) are usually found in central zones. Migrant villages and fishing villages are settled in tidal zones. Different types of villages are found in different habitats, but they are connected by a network. The connections between pangkalan villages and muara villages are especially strong. In the central zone, the lands suitable for agriculture are limited to small areas covered by mixed peat swamp forests, and the other areas can be used only as forests. As a result, people in the central zone (villagers of muara villages) have the closest relationships with forests. In this paper I describe the agricultural, fishing, and hunting practices, the dietary taboos, the logging methods, and the plant usage that I observed in the muara villages of Riau, in the Kampar region. I conclude that the most important reason to conserve peat swamp forests is to secure the survival of the people who live among them, (especially those who lack capital). I also point out that the network connecting the different kinds of villages plays important roles in enabling villagers to adapt quickly to changes in the environment and to avoid overexploitation. Taboos in diets are considered to contribute greatly to the villagers’ sense of belonging to the network at the level of everyday life. Since the recent political crisis in Indonesia, the government’s protection of the forests has been unreliable. The reason why forests still remain is that the Malays, an influential group, have prevented newcomers from devastating their lives, which are founded on close interaction with the forest.

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Only two feather mite species, Compressalges nipponiae Dubinin, 1950 (Astigmata, Freyanoidea, Caudiferidae) and Freyanopterolichus nipponiae Dubinin, 1953 (Astigmata, Pterolichoidea, Kramerellidae), are described from the Crested Ibis Nipponia nippon (Temminck, 1835) in Russia. Both mites have never been reported from other birds and are probably species-specific to the Crested Ibis. However, after the original descriptions, no collection records on the type host have been reported. We investigated the feather mite species compositions on forty nine specimens of the Crested Ibis, comprising the original Japanese population (six specimens), specimens raised in Japan but originating from Shaanxi Province, China (thirty two specimens), birds from the original Korean Peninsula population (nine specimens), and two specimens of unknown origin. As the result, F. nipponiae was found in all areas, but C. nipponiae was not found on any of the samples originating from China (Shaanxi Province). Specifically, species composition was the same in Japan and the Korean Peninsula. However, compared to that of these two regions, that in inland China (Shaanxi Province) differed. Recent genetic analysis detected systematic differences in Crested Ibis depending on the regions. For understanding the detail, we need to survey the symbiotic status in China. However, our results indicate partially that the difference between symbiotic feather mite corresponds to differences in the origin among the Crested Ibis populations.

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