Rainwater composition effect

Willey JD, Bennett RI, Williams JM, Denne RK, Komegay CR, Perlotto MS, Moore BM. Effect of storm type on rainwater composition in southeastern North Carolina. Environ. Sci. Technol. 1988 22 41-46. 

With emission source chemical signatures and corresponding aerosol or rainwater sample measurements PLS can be used Co calculate a chemical element mass balance (CEB). Exact emission profiles for the copper smelter and for a power plant located further upwind were not available for calculation of source contributions to Western Washington rainwater composition. This type of calculation Is more difficult for rainwater Chan for aerosol samples due Co atmospheric gas to particle conversion of sulfur and nitrogen species and due Co variations In scavenging efficiencies among species. Gatz (14) has applied Che CEB to rainwater samples and discussed Che effect of variable solubility on the evaluation of Che soil or road dust factor. 

Information available in the literature is restricted to isolated attempts to describe and quantify specific processes like litterfall and decomposition (Peres et al. 1983), rainwater composition (Schiavini 1983, Delitti 1984), soil fertility gradients (Lopes and Cox 1977), leaf nutrient concentrations (Haridasan 1987, 1992, Araujo and Haridasan 1988), primary productivity of the ground layer (Batmanian and Haridasan 1985, Meirelles and Henrique 1992), effects of burning (Coutinho 1990,... 

The effects of anthropogenic sulfur dioxide on the remote marine atmosphere may be evident from rainwater studies by Chukhrov et al. (60) in which the isotopic composition of sulfur in rain was studied systematically at great distances from the continent. Rainwater sulfate ranged from +12.1 to +15.0 0/00 over the Atlantic and from +9.5 to +16.2 0/00 over the Pacific, with a one month average value of +13.3 0/00 for the two oceans. Their study included measurements of rainwater sulfate from a wide variety of continental areas and found that most inland 634S values were significantly lower than those over the oceans. The oceanic rainfall sulfate was most likely a mixture of the isotopically lower continental sulfate and the more enriched marine sulfate. 

In Chapter 1, section 3 there is an account of the behaviour of rubber polymers. The brittle holder is an interesting example of control of Tg by means of the plasticizer content of a PVC composition. One of the important effects of plasticizer is to lower Tg. Unplasticized or rigid PVC, as used in rainwater goods and window frames has a Tg of 80 C. Addition of plasticizer (usually high boiling point esters) lowers Tg progressively, and softens the material. The effect is to impart elastomeric, or rubber, properties. Fig. 3.3 shows this. 

The hydrosphere is mostly composed of rainwater, river water, lake water, ground water, and ocean. The effect of human activity on the compositional variations of elements in the hydrosphere and soils will be considered below. 

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