Greening as strategic development in industrial change - Why companies participate in eco-networks

Networking between companies and other regional key actors has grown into a widespread instrument for economic development since the 1990s. Participatory networks have formed the concept for many activities of Local Agenda 21. Simultaneously, economic geography has focused on network theories to explain innovation in and the economic success of regions.This article focuses on the reasons why individual actors participate in environmentally oriented information networks. The questions approached are: Does the concept of learning within networks influence a firm’s development? How do the participants interact with each other? What effects do the networks have on their environment (arenas)?The changing arenas of a firm are analysed with regard to environmental concerns. These changes need to be anticipated for reliable strategies. To gain information and knowledge about current behaviour and activities, the functions of networks as learning platforms are discussed. Drawing upon arguments from different network theories, the motivations of participating in a network are threefold: actor and firm oriented, network internal (inter-firm), and network external. From these, a generic target cube of network motivations and actions is set up.The concept is reviewed by examining 12 ‘regional environmental information-oriented corporation networks’ (RUN) in the Greater Munich Area. The empirical material reveals that this type of network does not provide a guarantee for significant improvements in a firm’s environmental behaviour. However, participants learn about best practices while pursuing explicit or implicit aims as to influence their arenas.     

A survey of numerical methods for stochastic differential equations

The development of numerical methods for stochastic differential equations has intensified over the past decade. The earliest methods were usually heuristic adaptations of deterministic methods, but were found to have limited accuracy regardless of the order of the original scheme. A stochastic counterpart of the Taylor formula now provides a framework for the systematic investigation of numerical methods for stochastic differential equations. It suggests numerical schemes, which involve multiple stochastic integrals, of higher order of convergence. We shall survey the literature on these and on the earlier schemes in this paper. Our discussion will focus on diffusion processes, but we shall also indicate the extensions needed to handle processes with jump components. In particular, we shall classify the schemes according to strong or weak convergence criteria, depending on whether the approximation of the sample paths or of the probability distribution is of main interest.     

Carbon and hydrogen isotopic compositions of the NBS 22 and NBS 21 stable isotope reference materials: An inter-laboratory comparison

Measurement of 17 laboratories on the stable isotope reference materials, NBS 22 lubricating oil and NBS 21 graphite, resulted in a revised calibration on the PDB scale. NBS 22 ¹³C/¹²C ratios of all laboratories did not demonstrate a gausssian distribution. Therefore, values which resulted from direct comparison with NBS 20 carbonate standards were selected the mean value of which is $\text{?29.81 ± 0.06?}$; this value is recommended as new value for NBS 22. The reported variations in δ¹³C for NBS 21 were consistent within the accuracies for single meaurements; the mean value is ?28.16 ± 0.01. The variations of D/H ratios of NBS 22 also were consistent with the accuracy quoted, with a mean value of ?119?.     

Continuous,Direct Gas-Geochemical Monitoring in Hydrothermal Vents: Installation and Long-Term Operation on Nisyros Island (Greece)

In this paper the installation and long-term operation of a system for continuous monitoring of fumarolic gases is described. Several physicochemical and gas-geochemical parameters such as the concentration of CO₂, H₂S and CO in the fumarolic emissions, as well as the temperatures of the hydrothermal steam and soil in close vicinity of the fumarole and steam pressure are measured in short-time intervals (typically 15 seconds). Data are logged on-site and in parallel transferred to a remote station by digital telemetry. Specially developed software enables the real-time observation of the local conditions in the crater and full bidirectional control of the monitoring system. Fluctuations in the monitored parameters are also reported. From the data presented it can be concluded that environmental conditions (direction and strength of wind, precipitation) will interact with some of the parameters monitored. These influences can only be revealed by continuously operated monitoring systems.     

Effects of reduced salt concentrations on plant communities in the River Werra (Germany)

The reduction and equalization of the salt concentrations in the River Werra have resulted in a gradual recovery of the aquatic flora. Spatial high-resolution macrophyte mappings document the spread of the aquatic vascular plants in the middle and lower River Werra. Simultaneously, the plankton blooms have declined. Changes in the composition of the algal communities including diatoms also indicated lower salinity. In addition to the salinity, high nutrient concentrations, waste water discharges and structural degradation are important stressors in the River Werra as shown by e.g. low species richness of vascular plants and the common occurrence of pollution tolerant diatoms. From the existing data it is clear that an encompassing improvement of the ecological conditions in the River Werra can only be achieved by further restoration measures considering all stressors.     

Biological effects of anthropogenic salt-load on the aquatic Fauna: A synthesis of 17 years of biological survey on the rivers Werra and Weser

The reduction and the smoothened amplitudes of the chloride concentrations since 2000 have resulted in a gradual positive development of the aquatic fauna in the River Werra. In the salinized section of the river increasing species numbers have been determined along the salinity gradient, which shows maximum chloride concentrations of about 2500 mg/l, maximum potash concentrations at approximately 200 mg/l, and magnesia concentrations peaked at 320 mg/l. As an immediate consequence of the reduction in salt concentration the immigration of various caddis fly species into the lower River Werra was observed. The Number of taxa per sample rose from 5 to more than 30 in the lower Werra region. Changes in species-richness could be seen more frequently in river sections where chloride concentrations fluctuated around 1500 mg/l.     

Kristallisation granitischer schmelzen

To elucidate the problem regarding the genesis of granites and migmatites, the influence of a) anorthite component, b) mafic components, and c) composition of the fluid phase on the crystallization of, granitic melts has been experimentally studied. As starting material, an obsidian with an average granitic composition has been selected and mixtures of this obsidian with anorthite or biotite have been made. H₂O or diluted solutions of NH₃, HF or HCl have been used as a fluid phase. The experiments were conducted under 2000 bars gas pressure and under isochemical conditions. At the outset of each experiment obsidian and the mixtures have been melted under 2000 bars pressure and then the temperature has been brought down stepwise, in order, to study the sequence and temperature of crystallization directly from the melt. The results of these experiments are plotted on a series of quartz-orthoclase-albite (Q-Ab-Or) melt diagrams, so that a better comparison with the different granitic systems and with the simple Q-Ab-Or-H₂0 system ofTuttle andBowen, (1958) can be achieved. The melt or crystallization diagrams of these complex granitic systems under study, represent projections of the Q-Ab-Or-An (An= anorthite) tetrahedron on to the base Q-Ab-Or. In all these triangular diagrams, there are three regions of crystallization: quartz, plagioclase and alkalifelspar. These three regions of crystallization are separated from each other by three cotectic lines; which meet at a point: the eutectic point. The sequence of crystallization of the leucocratic minerals; observed in the different granitic systems investigated experimentally here, can be understood with the help of such diagrams easily. From these experiments the following petrogenetically interesting results have been obtained:

1. 1.
   The order of crystallization of granitic melts is to a great extent influenced: by the normative proportion of the Ab/An components and the composition of the fluid phase. (It is not the variation in the An content directly but the variation in the relative proportions of Ab/An, that causes a change in the order of crystallization.) In general, with decreasing Ab/An proportion in a rock or a melt, the amount of albite component in the.eutectic melt decrease,. while at the same time- the amount of quartz and orthoclase components increase. When the Ab/An proportion of a rock is more than 3.5, then the corresponding eutectic melt is of granitic composition; and when the proportion is lesser than 3.5 the eutectic melt is quartz and orthoclase rich and has aplitic composition. Calc-alkaligranites and alkaligranites have an average Ab/An proportion of 4.7 and 10.5, respectively.