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It is well known that temperature significantly affects corpse decomposition. Yet relatively few taphonomy studies investigate the effects of seasonality on decomposition. Here, we propose the use of the Köppen-Geiger climate classification system and describe the decomposition of swine (Sus scrofa domesticus) carcasses during the summer and winter near Lincoln, Nebraska, USA. Decomposition was scored, and gravesoil chemistry (total carbon, total nitrogen, ninhydrin-reactive nitrogen, ammonium, nitrate, and soil pH) was assessed. Gross carcass decomposition in summer was three to seven times greater than in winter. Initial significant changes in gravesoil chemistry occurred following approximately 320 accumulated degree days, regardless of season. Furthermore, significant (p < 0.05) correlations were observed between ammonium and pH (positive correlation) and between nitrate and pH (negative correlation). We hope that future decomposition studies employ the Köppen-Geiger climate classification system to understand the seasonality of corpse decomposition, to validate taphonomic methods, and to facilitate cross-climate comparisons of carcass decomposition.

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Diffusion phenomena are involved, directly or indirectly; in practically all fundamental plant processes, playing particularly important roles in the movement of substances into and out of plants and in the translocation of substances within the plant. In recent years the results of a number of different lines of investigation, which need not be cited here in detail, have increasingly indicated that energetically much more complex mechanisms than dliffusion are involved in the transfer of at least certain kinds of solute particles, and perhaps also water molecules, from the environment into the plant, from the plant into its environment, and from cell to cell within the plant. In spite of such more complex mechanisms which are superimposed on the kinetically and energetically simpler process of diffusion, this latter process does account principally or entirely for certain of the movements of materials which occur within a plant or between a plant and its environment. Furthermore, diffusion almost invariably accompanies, as a subsidiary or underlying mechanism, those processes in which the predominant niiechanism is thermodynamically more complex.The now generally recognized fact that diffusion is only the simplest of the mechanisms which play a part in the movement of substances into, out of, and within plants should not disincline us from attaining as clear an insight as possible into the dynamics of this process. A lucid picture of the kinetics of diffusion phenomena as they occur in relation to plants is necessary as a foundation for an understanding of other more complicated processes involved in the movement of materials in plants. In this paper little attempt is made to explain or conceptualize even the relatively simple phenomena of diffusion, but only to evaluate the terminology used in descriptions of such phenomena, and to make certain recommendations regarding preferences in such terminology. Any clarification or simplification in terminology which can be accomplished should, however, make possible a more effectual presentation of the concepts of diffusion.