A similarity criterion for forest growth curves

Comparison of forest growth curves has led many to the conclusion that there is a similarity between forest stands growing in different conditions. Here we treat the same subject from the viewpoint of similarity theory. Our goal is to form a dimensionless ratio of biophysical entities that could parameterize the diversity of forest growth curves. (Such ratios are called similarity criteria.) Pursuing this goal, we focus on the analogy between tree crown growth and atomic explosion. A blast wave is formed when the rate of energy release is much higher than the rate of energy dissipation. The difference between the rates of energy release and dissipation is the essence of this phenomenon. The essential feature of crown growth is the difference between the rates of non-structural carbohydrate supply and demand. Since the rate of supply is much higher than the rate of demand, the flow of non-structural carbohydrates achieves the tips of branches and enables the radial growth of crown. Proceeding from these ideas, we derived the similarity criterion which supposedly captures the “essence of growth” that emerges from the geometric similarity of tree crowns

Biospheric context of Siberian development

Productivity of ecosystems surrounding a city is important for supporting its activities in a sustainable way. The total terrestrial net primary production (NPP) shows biosphere potential to supply primary food energy source for all non-autotrophic species including humans. Humans appropriate approximately 20% of NPP, in average. Even in the relatively well-populated regions of Siberia, NPP per capita exceeds the average level by several times suggesting the window of opportunity for achieving sustainable development. (3 pages, 1086 words, 2 maps)
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Biospheric context of Siberian development

Recent publications on human appropriation of Net Primary Production (NPP) raise the question of how much of the biosphere’s productivity we can appropriate in a sustainable way. This article brings the issue into the context of Siberian development. In contrast to many other regions of the world, the population density in Siberia is still very low as compared to the NPP supplied by regional ecosystems. Hence, it is not too late to raise the question on how much of the NPP supplied by Siberian ecosystems we can appropriate in a sustainable way

An \u3cem\u3em\u3c/em\u3e-Carboranedicarboxylic Acid Dianilide

The crystal structure of the \u27non hydrogen-bonded\u27 (according to IR data) polymorph of 1,7-bis(phenylcarbamoyl)-1,7-dicarba-closo-dodecaborane(12), C16-H22B10N2O2, has been determined. The two phenylamide groups have a Z configuration [the torsion angles 0-C-N-C are -2.3 (5) and -3.0 (5)°]. As a result both \u27active\u27 protons of these groups are almost completely shielded by other H atoms of the neighbouring carborane nucleus and phenyl substituents, and, therefore, no hydrogen-bonding contacts are found

Who is Who in Carbon Balance and Management 2006

This editorial provides a subject index from published articles, active researchers, and published papers in the field of carbon balance and management

Forest cover: setting targets for the future

The International Year of Forests, declared by the UN, is a good occasion to discuss approaches to reducing forest degradation in developing countries. The articles collected in Thematic Forest Series form a diversity of ideas which is essential for setting the levels below which the countries' reduced emissions could be measured and credited. This editorial calls attention to the use of Land-Use/Land-Cover Change models

Percolation and number of phases in the 2D Ising model

We reconsider the percolation approach of Russo, Aizenman and Higuchi for showing that there exist only two phases in the Ising model on the square lattice. We give a fairly short alternative proof which is only based on FKG monotonicity and avoids the use of GKS-type inequalities originally needed for some background results. Our proof extends to the Ising model on other planar lattices such as the triangular and honeycomb lattice. We can also treat the Ising antiferromagnet in an external field and the hard-core lattice gas model on $Z^2$.Comment: 22 pages. Further details on extensions. To appear in J.Math.Phys., special issue on `Probabilistic Methods in Statistical Physics', March 200

Uniaxial pressure dependence of magnetic order in MnSi

We report comprehensive small angle neutron scattering (SANS) measurements complemented by ac susceptibility data of the helical order, conical phase and skyrmion lattice phase (SLP) in MnSi under uniaxial pressures. For all crystallographic orientations uniaxial pressure favours the phase for which a spatial modulation of the magnetization is closest to the pressure axis. Uniaxial pressures as low as 1kbar applied perpendicular to the magnetic field axis enhance the skyrmion lattice phase substantially, whereas the skyrmion lattice phase is suppressed for pressure parallel to the field. Taken together we present quantitative microscopic information how strain couples to magnetic order in the chiral magnet MnSi.Comment: 23 pages, includes supplemen