Wintertime atmospheric concentration of NSS-sulfate and SO₂ and fallout amount of NSS-sulfate were measured at 5 sites placed along the stream of NW monsoon, which blew over Chyugoku mountain. Rain and snow were classified to NW monsoon type and the other type based on the cause of rain and snow. In the case of NW monsoon type, peaks of fallout amount of many components existed just before the mountain, where air was going upwards. On the other hand, in the other cases, fallout amount was higher at the coast and mountain top than at the foot of the mountain. From the viewpoint of washout ratio, it was estimated that the place, where air was going upwards, had a higher washout ratio due to the acceleration by effective rainout.
Mass balance of total sulfur compounds was estimated from December 22 to 25 in 1992 as a model case. According to this calculation, about 14% of total atmospheric sulfur compounds was removed by the precipitation, while air passed over the mountain, which meant that bout 2% of sulfur compounds was removed by 10 km. The contribution of washout under the altitutde of 1000 m to the total fallout was estimated 68% in the plain area and under 35% in the mountainous area.

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The seedlings of Japanese cedar (Cryptomeria japonica D. Don), Japanese cypress (Chamaecyparis obtusa Endl.) and Japanese zelkova (Zelkova serrata Makino) were exposed for 24 weeks per year to four simulated profiles with diurnal fluctuations of ozone in enviironment-controlled greenhouses: 0.4 (×0.4), 1.0 (×1.0), 2.0 (×2.0) and 3.0 (×3.0) times the ambient followed average profile of the concentration observed at the outdoor in last two years. Experiments were repeated in 1993, 1994 and 1995. During the experiments, yearly seasonal averages of daytime 12-hr daily mean (daily 1-hr maximum) ozone concentration at×0.4, ×1.0, × 2.0 and ×3.0 were 16 (22), 39 (52), 74 (102) and 114 (159) ppb, respectively.
Japanese zelkova seedlings at two higher (×0.2 and×3.0) ozone treatments developed white fleck injuries followed yellowing, and defoliated in its early stage. Japanese cedar and cypress did not show any visible injury symptoms by ozone. After 24 weeks exposure in all experiments, total dry weights (TDW) of zelkova seedlings at the two higher ozone treatments significantly reduced compared with the lowest (×0.4) ozone treatment. Stem dry weight of zelkova at the ambient level (×1.0) of ozone treatment in 1995 were significantly less than those at the lowest treatment. TDW of cedar at the highest ozone treatment significantly reduced compared with the lowest treatment in 1993 and 1995. The relative growth rate and net assimilation rate of cedar and zelkova seedlings decreased with increasing level of ozone treatment. The net photosynthetic rates in Japanese cedar and zelkova leaves, measured throughout the 1993 experiment, decreased with increasing ozone. The growth and new photosynthesis of cypress seedlings were hardly affected by ozone.
These results indicated that Japanese zelkova is the most sensitive to ozone compared with less sensitive cedar and tolerant cypress by estimating growth inhibition, and that the ozone-induced reductions in growth was brought about mainly due to the inhibition of net photosynthesis leading to reductions in the efficiency of dry matter production.

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Anthropogenic emissions of nitrogen oxides (NO_x) and carbon dioxide (CO₂) in China were investigated to establish an emission inventory of air pollutants in East Asia. The total amounts of the emissions were classified by energy demand sectors, provinces, major cities, and two grid systems such as 80×80 km square and 1°×1°resolution.
Distinctive features of this work were determination of appropriate emission factors by carefully reviewing previous studies in Europe, U. S. A. and Japan, and taking combustion condition, type and size of furnace in China into account.
Based upon these emission factors, the total amounts of 6.7Tg of NO_x and 2543Tg of CO₂ were estimated to be emitted in China in 1990. In the category of fuel, “coal combustion” and in the category of energy demand sector, “power and heat generation” were the largest source of thermal comsumption and air pollutants emission respectively. Large amounts of air pollutants were discharged from coastal regions facing the Yellow sea and Bo hai, reflecting ecomomical growth and urbanization.

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The chemical components of airborne suspended particulate matter (SPM) and deposition were measured in samples collected at monthly intervals both at Happoone in the Karamatsu Mountains of the Japan Alps and in Nagano City. The contributions of several sources to SPM were estimated via the chemical mass balance (CMB) method. The amount of deposition at Happoone was compared with that in Nagano City, and its effects on stream water components was observed.
At Happoone, SO₄^2-concentration in the SPM increased from spring to summer. In spring, Kosa aerosol was detected in the SPM and its concentration was estimatedto be 4 μg/m³. Few soil particles generated from the neighboring area were detected in the SPM. The mean pH of deposition at Happoone was 5.1, slightly lower than that (5.3) in Nagano City, and the Happoone value increased during spring. The deposition rates of nss-SO₄^2- and NO₃^-at Happoone were 1.5 times greater than those in Nagano City. These results suggest that greater amounts of acidic substances fell on this mountain region, which had seemed to be a clean area.
The Hira River, a mountain stream near Happoone, had sufficient capacity to neutralize the acid deposition with pH remaining at 7.6 and alkalinity at 0.48 meq/l. However the alkalinity decreased temporarily due to dilution with rainfall during the rainy season. During the snow melt season, the concentration of NO₃^-increased, although pH decline was not observed.

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Fog water had been sampled on Mt. Akagi almost every fall since 1984 till 1992. Chemical species in fog water have been analyzed. Weather conditions under which fog water was sampled were classified into 5 patterns of weather map. To clarify the relationship between weather condition and pollution of sampled water, 2 kinds of cluster analysis were performed by using the nondimensional chemical equivalent concentration normalized by averaged value, and the ratio of 9 chemical species concentration in fog and rain water.
As a result, the former dendrogram showed that samples were distinguished to high, middle and low groups of total ion concentration contained, the latter was dominated by contents of sea salt in sample. Both results corresponded with weather patterns categorized in this study.
The equivalent N/S (NO₃^-/ nss-SO₄^2-) ratio in fog and rain water was larger than that of averaged in precipitations sampled in the whole Japan. Especially, the N/S ratio of fog water was considerably large, and varied by weather conditions.

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Hanshin urban area was attacked and destroyed by the tremendous earthquake at 5: 45 a.m. in January in 1995. The seismometer recorded a tremor of the 6-7 degree on the soismic scale. More than 5, 500 people were killed and, what was worse, there were fatalities of more than 10% of the above number due to the secondary damage.
The local NO₂ concentrations of the capsules set in the damaged areas were measured in the first day in June 1995. The health of inhabitants living there was also researched by mean of a questionnaire at the same time.
The following four respects were turned out through this survey.
1. NO₂ concentrations measured along the roads running not only from east to west (Route 2 and Route 43) but also from north to south were high.
2. Although NO₂ concentrations around the areas along the Osaka bay were not so high before the earthquake, they became higher after it, because a large number of trucks carried the wastes from the destroyed buildings passing through the bay road, and the combustible wastes were burned to form ashes in the bay areas.
3. The rate of the people who complained about health worsening after the earthquake reached 25% of those who replied to the questionnaire. Most of them complained about respiratory problems.
4. The relation between the NO₂ concentration and the rate of people, who lived in the same area, where the NO₂ concentration was measured, and who also complained about thsir health worsening after the earthquake, became clear with condition of 5% risk. The relations were turned out with the same risk between the NO₂ concentration and both the complaint rate of the respiratory symptoms and the rate of the adult (age over 18), who complained about their poor health.

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