Sustainable development and green national accounts

Defining sustainable development as non-declining utility, the relationship between sustainable development and optimal growth is examined critically in Part 1. The operation of the Hartwick rule for an exhaustible resource is explored under different values of the elasticity of substitution between capital and resources. The Hartwick rule is then extended to the case of fossil fuels, where carbon dioxide emissions arise as an externality. Optimal growth paths with exhaustible resources are shown to be non-sustainable for positive pure rates of time preference or if produced capital depreciates. For linked environment-economy models where pollution stocks dissipate, the optimal steady state is characterized and feasibility conditions for the steady state derived. When resources are renewable and production leads to emissions that damage the resource, the restrictions on the feasible resource stock size in the steady state are determined. Part 2 considers the problem of measuring sustainable development, deriving 'green NNP' as a transformation of the Hamiltonian function for an optimal control problem. Two problems in accounting for exhaustible resources are developed: resource discoveries and heterogeneous resource deposits. The key issue of the treatment of pollution and pollution abatement in green national accounts is explored through a series of six models: flow pollutants, stock pollutants, impairment of pollution dissipation, fossil fuels and carbon dioxide, living resources and acid rain, and household defensive expenditures. The models of flow accounts are extended to green wealth accounting, where it is shown that stocks of pollution can be treated as liabilities in the national balance sheet. Empirical measures of sustainable development are presented in Part 3, with a discussion of the policy implications of green national accounting. Estimates of the value of pollution and 'genuine' savings rates are presented for the UK and selected European countries. The genuine savings analysis is extended to resource depletion and carbon emission damages for over 50 developing countries, revealing significant dissaving in Subsaharan Africa

Ternary configuration in the framework of inverse mean-field method

A static scission configuration in cold ternary fission has been considered in the framework of mean field approach. The inverse scattering method is applied to solve single-particle Schroedinger equation, instead of constrained selfconsistent Hartree-Fock equations. It is shown, that it is possible to simulate one-dimensional three-center system via inverse scattering method in the approximation of reflectless single-particle potentials.Comment: 8 pages, 1 figure, iopart.cls, to be published in Int.J.Mod.Phys.

Seismic wide-angle study of accreted Proterozoic crust in southeastern Wyoming

A seismic wide-angle xperiment was conducted in southeastern Wyoming, USA to investigate the seismic character of a postulated Proterozoic magmatic arc south of the suture (Cheyenne Belt) to the Archean Wyoming Province. Recordings from vibrator and dynamite sources with offsets between 34 and 126 km reveal no evidence for Moho reflections. The large-offset recordings contain multicyclic bands of reflective phases from the middle to lower crust. The data were transformed into the intercept ime-ray parameter (~--p) domain to estimate local depth bounds. A subsequent 1D inversion using high-amplitude ~'-p arrivals shows that the reflective part of the crust ranges from the depths of 25 to 40 km. This part of the crust exhibits velocities increasing from about 6.5 to 7.5 km/s. Reflectivity modeling shows that the lower crust might consist of a zone of alternating low- and high-velocity layers with average velocity increasing. The average lower crustal velocity of about 6.9 km/s suggests a predomi-nantly mafic composition with interlayered intermediate to felsic components generating impedance contrasts that cause observable amplitudes from reflections at large offsets but not at clearly pre-critical and near-vertical distances. Our model is consistent with observations of interlayered sequences of gabbroic to ultramafic rocks with more felsic anorthositic and charnockitic rocks in the exposed lower crust of magmatic arc complexes. The lack of wide-angle Moho reflections might be explained by a gradational compositional boundary, or a transitional phase change from granulite to eclogite facies. 1

Information Outlook, April 2007

Volume 11, Issue 4https://scholarworks.sjsu.edu/sla_io_2007/1003/thumbnail.jp

Factors affecting ammonium uptake in streams - an inter-biome perspective

The Lotic Intersite Nitrogen experiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes. 2. Data were collected from 11 streams ranging from arctic to tropical and from desert to rainforest. Measurements at each site included physical, hydraulic and chemical characteristics, biological parameters, whole-stream metabolism and ammonium uptake. Ammonium uptake was measured by injection of \u275~-ammonium and downstream measurements of 15N-ammonium concentration. 3. We found no general, statistically significant relationships that explained the variability in ammonium uptake among sites. However, this approach does not account for the multiple mechanisms of ammonium uptake in streams. When we estimated biological demand for inorganic nitrogen based on our measurements of in-stream metabolism, we found good correspondence between calculated nitrogen demand and measured assimilative nitrogen uptake. 4. Nitrogen uptake varied little among sites, reflecting metabolic compensation in streams in a variety of distinctly different biomes (autotrophic production is high where allochthonous inputs are relatively low and vice versa). 5. Both autotrophic and heterotrophic metabolism require nitrogen and these biotic processes dominate inorganic nitrogen retention in streams. Factors that affect the relative balance of autotrophic and heterotrophic metabolism indirectly control inorganic nitrogen uptake