Biogeocenosis thermodynamics based on remote sensing
A.N. Severtsov Institute of Ecology and Evolution RAS
119071 Moscow, Leninskij pr., 33
e-mail: srobert_landy@mail.ru, puzak@orc.ru
Methodological issues in the studies of spatial and temporal variations in the energy conversion are shown to be solvable on the basis of information thermodynamic approach using the remote sensing techniques. A possibility of evaluation of the main components of the energy balance of a biogeocenosis, considered as an open thermodynamic system maintaining its structure through the conversion of solar energy, is demonstrated by analysis of the southern taiga landscapes of Valdai Hills. Analysis of the ratio of thermodynamic variables for the different types of biogeocenosis shows that the energy flow absorbed by the surface, is being redistributed among balance components by various mechanisms, and it depends on the structure of the redistribution system expressed by the non-equilibrium. Non-equilibrium of the solar energy transformation is determined before all by the energy costs in the synthesis of biological products, and has a little impact on exergy of the solar radiation, i.e. the cost of energy to evaporation. Invariance of energy conversion by landscape as a whole and generalized types of biogeocenoses are estimated. The ability of the taiga landscapes to maintain energy absorbed invariants, exergy and temperatures forms a naturally determined series similar to a succession trend: meadows - falls - deciduous forests - coniferous forest. Anthropogenic objects are shown to possess the weakest autoregulation ability. Raised bogs keep high heating of the territory and preserve precipitation in the subsurface runoff, in contrast to the forests carrying out moisture transport from the soil into the atmosphere. The bog's ability to maintain the level of biological production is comparable to that of coniferous forests. The role of forest vegetation in climate regulation is estimated; it is shown that the absence of forests increases the surface temperature by 4°C.
