Wet deposition of nss-sulfate, nitrate, ammonium and hydrogen ion in Kyushu, Japan was estimated on the basis of measurements of precipitation chemistry at 27 sites and rainfall amounts at 118 AMeDAS stations. The spatial distribution of the deposition obtained with γ^-2-interpolation scheme was compared with avaible measurements of precipitation chemistry and rainfall amounts to confirm acceptable accuracy of the estimaing scheme. The obtained distributions of seasonal ionic deposition strongly suggested that: 1) the deposition of nss-sulfate was rainfall limited, 2) that of nitrate was influenced by local emissions, and 3) ammonium deposition is dominated by rainfall amount and local emissions. Spatial distribution of nss-sulfate discerned that southwesterly airflow in Baiu and summer transported sulfur species emitted from Sakurajima, a volcano located in the southernmost of Kyushu, over 150 km to Kyushu Sanchi mountains, whereas sulfur from the Asian Continent significantly contributed the deposition in winter months over northern Kyushu due to northwesterly monsoon.

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Ten kinds of offensive odors were measured with an odor sensor and by a human sensory test simultaneously. Five kinds of odor were taken in the following facilities; kraft pulp factory, raw sewage treatment plant, stock raisings plant, rendering plant and FRP plant. Another 5 kinds of odors were typical offensive odors generated from living environment; tobacco smoke, kitchen refuse, toillet, grilled fish and sewage. As a result, significant correlations were found between the response values of the odor sensor and odor indexes for all samples. Sensitivity of the odor sensor used was not enough to detect some kinds of odorant at low concentration corresponding to odor index 10 which was the lowest odor standard. Odor index, however, could be predicted from response value of the odor sensor using regression equation between the odor indexes and the response values for each odorant if the concentration was enough to detect by the odor sensor.

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The rain water of Suita area located at hinderland of the industry zone and the dwelling zone was collected in the campus of Kansai university over 1993 to 1995, and the properties of these rain water were investigated. The average pH value of rain water was 4.82 for three years. The appearance percentage of rainfall below pH 5.6 was approximately 88%. The pH of rainfall showing the higher appearance frequency was 4.2-4.4 and 5.2-5.4, and these appearance percentages were 12.2% and 11.2, respectively. The contents of Cu²⁺ ion in the rain water was 27.0 μg/L as the average value, and was recognized to increase as pH becomes lower. The average value of electric conductivity was 23.6 μS/cm. Although the relationship between pH and electric conductivity showed some scatter, the electric conductivity increased remarkably as pH becomes lower than about 5.5, and also tended toward increase as pH becomes higher than about 5.5. The contents of major ion species, such as Na⁺, K⁺, NH₄⁺, Mg²⁺, Ca²⁺, NO₃^- and SO₄^2-, indicated the higher values in the initial rainfall of 1 mm, but decreased gradually with the increase of rainfall amounts, and were found to be approach to the approximately constant value over 3 mm of a rainfall amounts. The linear relationship was recognized between pAi=-log ([NO₃^-] + [SO₄^2-]) and the logarithm of electric conductivity (logλ). This straight line is represented by pA_i=-1.14λ·logλ+5.35. The mole ratio of Na⁺ to Cl^- at the other season, except for the summer season, was 1: 1.34 as the average value, and that of NH₄⁺ to nss-SO₄^2- was 1: 1.27. From such value, the considerable amounts of and SO₄^2- ions generated artificially, except for the sea-salt component, were found to be contained in the rain water of Suita area.

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Concentration differences of soluble constituents in precipitation samples, under five different preservation methods, were compared. The samples collected at Niigata, Japan in early winter and spring were preserved 21 to 59 days in 100 mL polyethylene bottles. Examined preservation methods were as follows:(A) Untreated, preserved at room temperature;(B) Filtrated (using a well washed membrane filter, pore size: 0.45μm), preserved at room temperature;(C) Added thymol (40 mg/100 mL), preserved at room temperature;(D) Untreated, preserved in a refrigerator (4°C) and (E) Filtered, preserved in a refrigerator.
Thymol-addiiton, which did not intefere with determination of constituents in precipitation, was an effective method for original H⁺ (organic acids, such as formic and acetic acids) and the NH₄⁺ cncentratiorn. Refrigeration was the next useful preservation method except for organic acids. Filtration was effective in reducing Ca²⁺ concentration change induced by dissolution of suspended matter in precipitation samples. From these results, it is recommended that when a refrigerator is not available even if samples are collected by wet-only sampler and/or organic acids are involved in measuring parameters, thymol should be placed in the sample collection bottles beforehand, and after collection, suspended substances in precipitation samples and residual crystals of thymol should be eliminated by filtration at a laboratory as a pretreatment for ion chromatography.

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