Solution‐culture studies of the toxicity of nitrites to plants were undertaken, using several rapidly growing species as indicator plants. Three to four weeks' growth of the test plants in complete nutrient solutions containing graded amounts of nitrous acid (varying nitrite and pH levels) disclosed that growth inhibition in the pH 4.0, 5.0, and 6.0 solutions was related to the undissociated nitrous acid fraction. Experiments with tomato plants suggested that a given concentration of nitrous acid is less injurious to the plant when the nitrogen assimilable by the plant is supplied as nitrate rather than as ammonium.

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Concentrations and fluxes of Cl‐ and Na+ in bulk precipitation and throughfall in an inland, acidic peatland (Alton Bog, Maine, USA) reveal the influence of canopy structure on the deposition rate of road‐salt and nutrient‐bearing aerosols. Alton Bog borders a four‐lane highway that is salted in winter. In open areas of the peatland steep gradients occurred in both Cl‐ and Na+ influxes in bulk precipitation and in surface‐water concentrations within ≈ 200 m of the highway. In winter, wooded sites had consistently higher atmospheric influxes of Cl‐ (up to 4X) than did treeless sites at the same distance from the highway. These results were consistent with expectations based on studies of dry deposition in nonpeatland areas. The increased influx of Cl‐ at wooded sites implies a significantly higher total influx of nutrients in peatlands where trees occur (especially unevenly spaced trees of mixed heights) than in peatlands with no trees. The effect is likely to be especially important in peatlands that receive all or most incoming nutrients from the atmosphere

Synopsis Although triphenylsulfonium chloride (TPS‐Cl) produced only small changes in water stable aggregation and hydraulic conductivity, it reduced the modulus of rupture values appreciably on all soils tested. Modulus of rupture values obtained from soils treated with TPS‐Cl were equal to or lower than those obtained from soils treated with ferric sulfate or VAMA.

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