Recently, the distribution of sika deer (Cervus nippon) has been expanding, and the consequent damages to crops and forests are increasing. Clarification of factors influencing this expansion might help in controlling an expansion of damaged areas. In this analysis, we hypothesized that the variables of expanding distribution vary according to the distance from source habitats. Therefore, we attempted to reveal the factors of expanding distribution by using several analysis ranges.
A generalized linear model (GLM) was used to derive predictive habitat distribution models from vegetational, topographical, and social predictors in a geographic information system (GIS), using the sika deer data in Honshu, Shikoku, and Kyushu, Japan, collected in the national survey on natural environment in 1978 and 2003.
The results showed that snow depth and population were important variables in the whole area model without distance from source habitats. On the other hand, distance was strongly associated with the distribution in the whole area model with distance. Furthermore, results from models employing smaller analysis ranges revealed that the sika deer distribution is influenced by cultivation abandonment, conifer and roads. This result implies that to prevent an expansion of damaged areas, cultivation abandonment and conifer should be managed.

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A carbon tax based on the imputed price of carbon (ICT) is an international tax with tax rates that differ among countries according to their economic levels. Although the effects were analyzed from the short-term perspective in the previous study, understanding the longer-term effects of ICT is significant considering the characteristics and urgent necessity of future climate change policies. This study purposes to analyze the mid-term (until 2050) impacts on environment and economy by applying a dynamic CGE model, and comparing ICT with an internationally common carbon tax (CCT).
As a result, a tradeoff between economic equity and CO₂ emissions abatement occurs between ICT and CCT. From the emissions abatement aspect, CCT is superior to ICT. However, considering the economic aspects simultaneously, the suitability of CCT diminishes. While the negative influence on GDP is smaller in developing countries than in developed countries under ICT, it is larger in developing countries under CCT. Furthermore, disparities of per capita GDP among the regions are narrowed more under ICT, meaning that economic equity progresses further. In the light of significance of the worldwide introduction of CO₂ abatement policies and avoidance of excessive burdens on developing countries, ICT is regarded as a highly feasible carbon tax policy.

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The nutrient properties of the foliage and soil of the Oku-Nikko region in Tochigi Prefecture, central Japan, were investigated to understand the mechanism of forest decline in this region. The foliar Mg concentration and Mg/Ca ratio were lower in Tsuga diversifolia (Maxim.) Masters collected from the Oku-Nikko region rather than in specimens from other sub-alpine regions. Furthermore, the concentration of exchangeable Mg and the exchangeable Mg/Ca ratio of soils from the Oku-Nikko region were lower than in other sub-alpine regions in all horizons. The soils in the Oku-Nikko region had the same pH and the same exchangeable Al concentrations as those in other sub-alpine regions. Therefore, it is difficult to postulate that Mg had leached from every horizon as a result of acid deposition in the Oku-Nikko region. Since every horizon had a constant Mg/Ca ratio, this soil property is probably a geological origin. The results indicated that soil acidification had not accelerated, but the soil properties affect the low Mg level in the foliage of Tsuga diversifolia, one of the declining species in the Oku-Nikko region. In this region, Mg deficiency in Tsuga diversifolia resulting from low soil Mg might decrease the species tolerance to various environmental stresses.

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