How does climate change adaptation affect public budgets? Development of an assessment framework and a demonstration for Austria

Mitigation and Adaptation Strategies for Global Change - Public adaptation to climate change affects government budgets directly on the expenditure side, but also indirectly via changes in the tax...     

Investigation of briquetting of metal waste from the bearing industry.

An economical method to process the metal waste that comes from the ball-bearing industry is presented. The purpose of the study was to determine the physical-chemical properties of the material, to present the most suitable binders and identify the factors that can affect briquette strength. The mechanical strength and resistance to gravitational drop were defined for both fresh briquettes and those that had been seasoned. The briquette structure was also tested. On the basis of the results of experimental studies and laboratory trials two techniques for processing the waste from the ballbearing industry on an industrial technological scale were developed. The economic and ecological impacts of these industrial applications were examined. The results of the investigations suggest that the briquettes might be recycled in steel-making furnaces. The reported solution to the problem of management of this type of waste appears to be universal and could also be applied by other waste-related enterprises.     

A complex social structure with fission–fusion properties can emerge from a simple foraging model

Precisely how ecological factors influence animal social structure is far from clear. We explore this question using an agent-based model inspired by the fission–fusion society of spider monkeys (Ateles spp). Our model introduces a realistic, complex foraging environment composed of many resource patches with size varying as an inverse power law frequency distribution with exponent β. Foragers do not interact among them and start from random initial locations. They have either a complete or a partial knowledge of the environment and maximize the ratio between the size of the next visited patch and the distance traveled to it, ignoring previously visited patches. At intermediate values of β, when large patches are neither too scarce nor too abundant, foragers form groups (coincide at the same patch) with a similar size frequency distribution as the spider monkey’s subgroups. Fission–fusion events create a network of associations that contains weak bonds among foragers that meet only rarely and strong bonds among those that repeat associations more frequently than would be expected by chance. The latter form subnetworks with the highest number of bonds and a high clustering coefficient at intermediate values of β. The weak bonds enable the whole social network to percolate. Some of our results are similar to those found in long-term field studies of spider monkeys and other fission–fusion species. We conclude that hypotheses about the ecological causes of fission–fusion and the origin of complex social structures should consider the heterogeneity and complexity of the environment in which social animals live.     

Dynamic growth model for Scots pine (Pinus sylvestris L.) plantations in Galicia (north-western Spain)

In this study we developed a dynamic growth model for Scots pine (Pinus sylvestris L.) plantations in Galicia (north-western Spain). The data used to develop the model were obtained from a network of permanent plots, of between 10 and 55-year-old, which the Unidade de Xestión Forestal Sostible (Sustainable Forest Management Unit) of the University of Santiago de Compostela has set up in pure plantations of this species of pine in its area of distribution in Galicia. In this model, the initial stand conditions at any point in time are defined by three state variables (number of trees per hectare, stand basal area and dominant height), and are used to estimate stand volume, classified by commercial classes, for a given projection age. The model uses three transition functions expressed as algebraic difference equations of the three corresponding state variables used to project the stand state at any point in time. In addition, the model incorporates a function for predicting initial stand basal area, which can be used to establish the starting point for the simulation. This alternative should only be used when the stand is not yet established or when no inventory data are available. Once the state variables are known for a specific moment, a distribution function is used to estimate the number of trees in each diameter class, by recovering the parameters of the Weibull function, using the moments of first and second order of the distribution (arithmetic mean diameter and variance, respectively). By using a generalized height–diameter function to estimate the height of the average tree in each diameter class, combined with a taper function that uses the above predicted diameter and height, it is then possible to estimate total or merchantable stand volume.     

Removal of nutrients and heavy metals from anaerobic waste by aerobiological treatment

This study was conducted to investigate the effectiveness of aerobic biological treatment in removal of nitrogen, phosphorous, and heavy metals from a unique anaerobic liquid waste, produced at a solid waste-to-methane anaerobic digestion facility. Laboratory scale continuous flow activated sludge reactors were employed in this study. The liquid waste has moderate BOD/COD ratio with BOD concentration of 1300 mg/L and high concentration of essential nutrients, making the liquid waste biologically treatable. Results showed that aerobic biological treatment can remove nitrogen and phosphorous on the order of 85%. Metal removal efficiencies vary widely for 11 metals studied in this investigation.     

Beta diversity at different spatial scales: plant communities in organic and conventional agriculture.

Biodiversity studies that guide agricultural subsidy policy have generally compared farming systems at a single spatial scale: the field. However, diversity patterns vary across spatial scales. Here, we examined the effects of farming system (organic vs. conventional) and position in the field (edge vs. center) on plant species richness in wheat fields at three spatial scales. We quantified alpha-, beta-, and gamma-diversity at the microscale in 800 plots, at the mesoscale in 40 fields, and at the macroscale in three regions using the additive partitioning approach, and evaluated the relative contribution of beta-diversity at each spatial scale to total observed species richness. We found that alpha-, beta-, and gamma-diversity were higher in organic than conventional fields and higher at the field edge than in the field center at all spatial scales. In both farming systems, beta-diversity at the meso- and macroscale explained most of the overall species richness (up to 37% and 25%, respectively), indicating considerable differences in community composition among fields and regions due to environmental heterogeneity. The spatial scale at which beta-diversity contributed the most to overall species richness differed between rare and common species. Total richness of rare species (present in < or = 5% of total samples) was mainly explained by differences in community composition at the meso- and macroscale (up to 27% and 48%, respectively), but only in organic fields. Total richness of common species (present in > or = 25% of total samples) was explained by differences in community composition at the micro- and mesoscale (up to 29% and 47%, respectively), i.e., among plots and fields, independent of farming system. Our results show that organic farming made the greatest contribution to total species richness at the meso (among fields) and macro (among regions) scale due to environmental heterogeneity. Hence, agri-environment schemes should exploit this large-scale contribution of beta-diversity by tailoring schemes at regional scales to maximize dissimilarity between conservation areas using geographic information systems rather than focusing entirely at the classical local-field scale, which is the current practice.     

Anthropogenic subsidies alter stream consumer-resource stoichiometry, biodiversity, and food chains.

Urbanization is dramatically changing nutrient and organic matter regimes in streams, yet the community and ecosystem implications often remain obscure. We assessed the consequences of sewage-derived particulate organic matter (SDPOM) for invertebrate community structure and function in a headwater stream. Using stable isotope analyses, we found assimilation of organic SDPOM to double community secondary production, and stoichiometric analyses revealed SDPOM enriched in phosphorus (P) to foster putatively fast-growing, P-rich consumers in the subsidized reach. This altered consumer-resource stoichiometry impacted both community structure and nutrient fluxes through the invertebrate community. Community structure shifted toward significantly reduced diversity and evenness in the subsidized reach and consequently toward shorter food chains. Our integration of ecological stoichiometry with stable isotope analyses and food web ecology expands the previous focus of traditional ecotoxicology and ecophysiology to an ecosystem-level appreciation of pollutant ecology.     

Sources of pesticides in surface waters in Switzerland: pesticide load through waste water treatment plants--current situation and reduction potential

Concentrations of pesticides in Swiss rivers and lakes frequently exceed the Swiss quality goal of 0.1 microg/l for surface waters. In this study, concentrations of various pesticides (e.g., atrazine, diuron, mecoprop) were continuously measured in the effluents of waste water treatment plants and in two rivers during a period of four months. These measurements revealed that in the catchment of Lake Greifensee, farmers who did not perfectly comply with 'good agricultural practice' caused at least 14% of the measured agricultural herbicide load into surface waters. Pesticides, used for additional purposes in urban areas (i.e. protection of materials, conservation, etc.), entered surface waters up to 75% through waste water treatment plants.     

TCE recovery mechanisms using micellar and alcohol solutions: phase diagrams and sand column experiments

Forty-one phase diagrams and fifteen sand column experiments were conducted to evaluate the efficiency of three types of washing solutions to recover trichloroethylene (TCE) at residual saturation and to identify the recovery mechanisms involved. This study demonstrates that: (1) an alcohol and a surfactant combination is more efficient than an alcohol used alone in water; (2) the prediction of the dominant recovery mechanism from the tie line slopes in phase diagram is accurate and can be reproduced in sand column experiments; and (3) TCE recovery efficiency in sand column experiments is generally well represented by the position of the miscibility curve in phase diagrams in the low concentration range. However, the miscibility curve alone is not sufficient to exactly predict the TCE recovery mechanisms involved. Tie line slopes and the critical tie line have to be taken into consideration to select the active matter as well as its concentration and to predict the dominant recovery mechanism in sand column experiments. The sand column experiments quantified the recovery efficiency of each solution and identified the proportion of the recovery mechanisms (mobilisation vs. solubilisation). Washing solutions with an active matter concentration above the critical tie line caused dominating mobilisation. Mobilisation was also dominant when the active matter of the washing solution partitioned into the organic phase and the active matter concentration was below the critical tie line. Solubilisation and emulsification were dominant for washing solutions containing active matter, which principally partitioned into the aqueous phase and an active matter concentration below the critical tie line.