Substantial efforts have been made to regulate pollution in Japan, and the stringency of pollution regulations such as sulfur oxides (SO_x) and nitrogen oxides (NO_x) have continued to increase over years. Technological innovations can play a key role in raising standards of living while improving environmental quality. Well-designed environmental regulations encourage innovation, while poorly designed regulations can inhibit its progress. This study uses patent data as a proxy for technological innovation over 1964 and 2002 and tests the direction of causality between the innovation and environmental regulations. In both of the cases, we find statistically significant effects of the regulations to the innovations. Finally, we test whether higher innovation leads to more stringent environmental regulations and find mixed results. The results suggest that we must be careful to maintain a realistic view of the potential for environmental regulations.

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Three typical Japanese needle-leaved trees (Cryptomeria japonica, Chamaecyparis obtuse, and Pinus densiflora) and a broadleaf tree (Quercus serrata) were exposed to ozone concentrations of 200 ppb and 100 ppb in a growth chamber. During the 3-day experiment, the species were exposed to ozone on the second day and BVOC emissions were measured daily from 7 a.m. to 7 p.m. Due to ozone exposure, monoterpene emissions from needle-leaved trees decreased and this effect continued until the next day. α-pinene emission was strongly affected by the ozone concentration. β-pinene was also affected by the ozone concentration, but the dependency of ozone concentration was weaker than α -pinene. Isoprene emission from Quercus serrata was slightly decreased by 200 ppb ozone exposure, but was not significantly affected by 100 ppb ozone exposure.

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Material flow analysis is a powerful method for achieving a zero emission society goal. It applies the concepts of industrial ecology to study how materials and energy flow into, throughout, and out of a system. The aim of this study is to estimate the material flow in Yamanashi Prefecture from the viewpoint of time-series using physical distribution census data. The census has been improved through nationwide researches by government organizations every five years. The author calculates the input, output and throughput of material with reference to other statistics, e.g. census of manufactures, input output tables, industrial wastes, final energy consumption and carbon dioxide emission. etc. The mass balance of Yamanashi Prefecture changed from the plus 4, 145 kiloton into the minus 4, 218 kiloton in ten years. Especially, the amount of the mining goods i.e. gravel, sand and stone shipped outside the prefecture has decreased. In addition, this study proposes the factor analysis on a change in the amount of waste referred to as the Kaya Identity Equation. The amount of the waste in 1995 increased because the third industry became active while the second industry stagnated. On the other hand, it was an effect of reduce that the amount of waste in 2000 decreased with a core of the second industry, and was related most the change in the production activity of mining. It is useful to analyze the material flow from the viewpoint of the time-series.

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Traditionally, land use change has involved forests being turned into farmland. However, this may change now that forestry has become recognized as a method to reduce the effects of climate change. Carbon credit systems will increase the productive value of forests which may reduce the occurrence of forested land being turned into farmland and result in the afforestation of unused land. If less forested land is turned into farmland, there is speculation that there will be complementary pressure on food production; however, detailed study has not been done on this issue. The current research involved developing a method to predict the potential of land use change upon the introduction of a carbon credit system using a numerical model. In particular, we considered conversions from forested land to farmland and the afforestation of unused land due to the introduction of a carbon credit system. First, we investigated the reasons for land use change by looking at differences in land use change that result from different scenarios. Next, we considered how land use would change as a result of introducing a carbon credit system. Finally, we investigated the effect of carbon price predictions on increases in forest areas in order to determine trends in future development. The current research differs from research involving traditional land use models because we used a mesh-based land use prediction model that uses the productivity of agriculture and forestry obtained from mesh and a global land cover map. We found that Africa was particularly sensitive to differences in land use that result from different scenarios. We also found that the introduction of a carbon credit system will reduce the amount of land that is converted to farmland and that if the carbon credits appreciate in value, there will be an even greater reduction.

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There is little information on environmental hazard of nanomaterials due to its unique physicochemical properties and biological interactions. In the present study, acute toxicity tests for fullerene C₆₀ using aquatic organisms were conducted to investigate the effects of the substance on the aquatic ecosystem. An aqueous suspension of fullerene C₆₀ (500 mg/L) which included nano-sized particles was prepared by grinding with sugar candy and polyoxyethylene hydrogenated castor oil for the tests. A 96-h acute toxicity test with medaka (Oryzias latipes), a 48-h acute immobilization test with Daphnia magna and a 72-h algae growth inhibition test with Pseudokirchneriella subcapitata were conducted using this aqueous suspension of fullerene C₆₀ according to the existing OECD test guidelines . As a result, the 96-h LC50 (median lethal concentration) for medaka, the 48-h EC50 (median effective concentration) for D. magna and 72-h EC50 for algae based on the growth rate (0-72 h) were estimated to be larger than 2.15, 2.25 and 2.27 mg/L, respectively. However, in the algae test, the growth rate (0-72 h) was significantly inhibited in the groups exposed to 0.0551-mg/L and higher concentrations of fullerene C₆₀. This result indicated that the 72-h NOEC (no observed effect concentration) based on the growth rate (0-72 h) was estimated to be 0.0178 mg/L.

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National food requirements have been estimated covering 184 countries from 1990 to 2100 based on the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) for providing information help to evaluate the impact of climate change on food security. Projections are carried out for ninety-six food items in FAO' food balance sheets (FBS) so that the proportion of undernourished in total population may be below 2.5 % throughout the projection period. These estimations are nearly equivalent to supply for domestic utilization in FBS, which is comprised of utilization elements such as feed, seed, food manufacture, waste and final use. Consequently, world cereal requirements in SRES Al and B1 scenarios reach 3, 406 million tones and 3, 426 million tonnes in 2050 respectively and decrease to 2, 650 million tonnes in 2100. On the contrary, those in A2 and B2 scenarios continue to increase to 3, 908 million tones and 3, 740 million tonnes in 2050 and reach 6, 010 million tones and 4, 030 million tonnes in 2100. A number of today's food-insecure countries seem likely to have overcome their food access problems by 2030, with much of the remaining food security problem concentrated in sub-Saharan Africa due to low person's income levels and rapid increases in food requirements.

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