The heating of the plasma in the solar atmosphere is discussed within bothframeworks of fluid and kinetic drift wave theory. We show that the basicingredient necessary for the heating is the presence of density gradients inthe direction perpendicular to the magnetic field vector. Such densitygradients are a source of free energy for the excitation of drift waves. We useonly well established basic theory, verified experimentally in laboratoryplasmas. Two mechanisms of the energy exchange and heating are shown to takeplace simultaneously: one due to the Landau effect in the direction parallel tothe magnetic field, and another one, stochastic heating, in the perpendiculardirection. The stochastic heating i) is due to the electrostatic nature of thewaves, ii) is more effective on ions than on electrons, iii) acts predominantlyin the perpendicular direction, iv) heats heavy ions more efficiently thanlighter ions, and v) may easily provide a drift wave heating rate that isorders of magnitude above the value that is presently believed to be sufficientfor the coronal heating, i.e., $\simeq 6 \cdot 10^{-5} $J/(m$^3$s) for activeregions and $\simeq 8 \cdot 10^{-6} $J/(m$^3$s) for coronal holes. This heatingacts naturally through well known effects that are, however, beyond the currentstandard models and theories.
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