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In the agamic generation of a cynipid wasp, Aphelonyx glanduliferae, variation in the survivorship among 5 years (on a Quercus serrata tree, T1) and refuge from parasitoid attack in relation to gall size was examined. Furthermore, the survivorship of the cynipid was compared among 7 trees (T1-T7), although analyses were based on data sets of 4 tree categories: T1, T2, T3, and others.
On T1, less than 2% of the cynipid survived in the latter 4 years. Gall density on 11 Q. serrata trees around T1 (within 50 m in distance) was conspicuously lower than that on T1, suggesting that the cynipid adults scarcely immigrate from other trees to T1. Thus, the survival rate on T1 should be usually lower than 2%. The survivorship of the cynipid was mostly affected by parasitoids. Although gall abortion and disease was also main causes of death of the cynipids in some years, the mortality rates by these factors varied among years. Therefore, refuge from parasitoid attack is likely to be a factor of critical importance in maintaining population levels of the cynipid. More cynipids survived parasitoid attack in larger galls, indicating that large galls provide refuge from parasitoid attack. The proportion of the cynipids that had survived parasitoids was not significantly affected by the statistical interaction between year and gall size. This suggests that the effect of gall size on the refuge from parasitoid attack is relatively fixed among years.
The survival rate of the cynipids did not differ among trees. However, the main mortality factors differed among trees. On T1 and T3, ca. 80% of the cynipid had been attacked by parasitoids. On T2, 75% of the cynipid had died of gall abortion.
Gall abortion of the agamic generation of the cynipid is most likely to be caused by the degradation in the quality of host plant tissues. The differences in the mortality by gall abortion both among years and among trees would be induced by the variation in the quality of host plant tissues. Gall size, which showed the relatively fixed effect on the refuge from parasitoid attack, are known to be regulated by host plant traits. Therefore, if the size of the cynipid galls varies among trees, this could also induce variations in the survivorship of the cynipid.

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We hypothesized that logging would greatly affect the species-specific microhabitats of carabid beetles. To test this hypothesis, we studied the carabid assemblages at Kamigamo Experimental Station, Kyoto, Japan, from June 1999 to May 2001, in three experimental (logged) and three control plots. The area of the experiment was categorized as a forested area that had experienced relatively little disturbance, in terms of species composition. In total, 303 individuals of 13 carabid species were collected in the study plots.The numbers of large carabid beetles, i.e., Carabus dehanii, Ca. yaconinus, Ch. posticalis, and Haplochaenius costiga, decreased because of logging, whereas Synuchus arcuaticollis and S. cycloderus may not have been negatively influenced by logging. The weight of the FH layer significantly affected the total number of P. latemarginatus, and marginally affected the number of S. cycloderus. However, soil water content (%) and the mean weight of the L layer did not affect the total number of beetles in any species. These results imply that the richness of the FH layer and vegetation, i.e., the potential food abundance and habitat richness, is more involved than soil moisture in determining species richness and density of the carabid assemblages.

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This is a fieldwork about the transition of land use and occupation at a natural village in moutaineous area of Fujian Province, China. After a pavement reached to the village in 1986, the villagers changed their occupations from rice farming for their self-sufficiency to gathering pine timber. After pine trees ran dry around 1994, they began mainly manage chestnut field and bamboo forest for producing commodity. Rice field area has been decreasing all thorough the time after the nation's shift to a route of reform and liberalization. Half of villagers now live in town near the village. They keep on managing chestnut field and bamboo forest besides making other jobs outside home village.

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The demand system for house construction by structure type was estimated to investigate the dependence of wooden house construction demand on prices by structure type and the expenditure on house construction. For each of 46 prefectures in Japan, I estimated LA/AIDS with 24 years time-series data. Compensated own price elasticity of wooden house construction demand was -0.28 on average, and the expenditure elasticity was 1.02. Other price elasticity estimates are generally small to show that demands are inelastic. In a simulation that assumed 3 to 30 thousands yen per carbon ton of carbon tax as of 1997, the impact of tax introduction on wooden house construction demand was observed small, and it was considered that the size of the impact depended significantly on the size of adjustment occurred in total expenditure on house construction.

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