Multi-criteria decision analysis in adaptation decision-making: a flood case study in Finland

Decision-making for the purpose of adaptation to climate change typically involves multiple stakeholders, regions and sectors as well as multiple objectives related to the use of resources and perceived benefits. Standard cost–benefit analysis can be argued to take into account easily monetised effects only. Multi-criteria decision analysis (MCDA) embedded in participatory processes can therefore play an important role in defining the decision context and exploring stakeholders’ preferences. In this paper, a case study on flood protection of the Kokemäki river running through the city of Pori in West Finland was conducted. The study was realised as a MCDA workshop involving the key stakeholders of the region. The analysis produced a robust ranking of the considered flood protection alternatives. According to the stakeholders, the approach was useful as an exploratory way of gaining a deeper and shared understanding of the flood protection. It was shown that MCDA is well suited for decision-making in adaptation to climate change–enhanced extreme events.     

Flooding and the Distribution of Selected Metals in Floodplain Sediments in St. Maries, Idaho

The link between sediment contamination and flooding is not well established, since flooding may exacerbate problems by spreading pollutants throughout the floodplain, or alternatively may dilute contaminants in source areas. To determine the substance of such relationships, the pattern of sediment contamination was examined in a small Idaho town following flooding in 1996. Four heavy metals were tested, nickel, chromium, zinc and copper, in 97 soil samples obtained from sites across the floodplain of the St. Joe River. Flood history and land-uses at each sample site were noted. Results showed that contamination levels generally were not high, with flood areas having lower concentrations than non-flood areas. A stronger relationship could be argued for land-use, with higher concentrations of contamination associated with some industrial sites. High levels of contamination were also found in several samples taken from recreational areas. Further research looking at the potential sources of contamination in relation to characteristics of the flood hydrology would seem pertinent.     

Strategic planning harnessing urban policy mobilities: the gradual development of local sustainability fix

The aim of our article is to follow how global policy models affect local policy making. Each city has unique local challenges in promoting development, e.g. economic growth, but also needs to find a balance between these targets and demands for sustainable city solutions. In our empirical study, we follow how ideas of waterfront development – to attract new inhabitants and promote economic growth – and global demands of carbon control were used interactively in a strategic spatial planning process in the city of Tampere, Finland. During the six-year planning process, these two policy targets became interdependent, created a new policy-making domain, and led to a combinatorial development of sustainability elements arising from this domain. These findings demonstrate the serial use of global policy models in the creation of a local urban ‘sustainability fix’. To conclude, the intertwinement of diverse global policy models in a city planning process creates easily a recursive cycle that redefines urban sustainability within cities and intercity networks. This perspective makes local policy narratives and strategic planning highly important in urban sustainability research as promoting urban sustainability becomes an inherently ambivalent practice.     

Predicting the sensitivity of fishes to dioxin-like compounds: possible role of the aryl hydrocarbon receptor (AhR) ligand binding domain

Dioxin-like compounds are chronically toxic to most vertebrates. However, dramatic differences in sensitivity to these chemicals exist both within and among vertebrate classes. A recent study found that in birds, critical amino acid residues in the aryl hydrocarbon receptor (AhR) ligand binding domain are predictive of sensitivity to dioxin-like compounds in a range of species. It is currently unclear whether similar predictive relationships exist for fishes, a group of animals at risk of exposure to dioxin-like compounds. Effects of dioxin-like compounds are mediated through the AhR in fishes and birds. However, AhR dynamics are more complex among fishes. Fishes possess AhRs that can be grouped within at least three distinct clades (AhR1, AhR2, AhR3) with each clade possibly containing multiple isoforms. AhR2 has been shown to be the active form in most teleosts, with AhR1 not binding dioxin-like compounds. The role of AhR3 in dioxin-like toxicity has not been established to date and this clade is only known to be expressed in some cartilaginous fishes. Furthermore, multiple mechanisms of sensitivity to dioxin-like compounds that are not relevant in birds could exist among fishes. Although, at this time, deficiencies exist for the development of such a predictive relationship for application to fishes, successfully establishing such relationships would offer a substantial improvement in assessment of risks of dioxin-like compounds for this class of vertebrates. Elucidation of such relationships would provide a mechanistic foundation for extrapolation among species to allow the identification of the most sensitive fishes, with the ultimate goal of the prediction of risk posed to endangered species that are not easily studied.     

Parasitismus und ‘Endokrine Disruption’ in Fischen

Background

Since the 1960s the scientific community has become increasingly aware of the need for integrative and holistic approaches to solve environmental issues. It has not only been recognized that changing environmental conditions can alter toxicological properties of pollutants but also that susceptibility of organisms to man-made chemicals strongly depends on environmental factors. This is especially true with respect to the endocrine control of reproductive processes in many aquatic species including fish, which are mainly influenced by changes in the surrounding environment such as day length, temperature, water flow, etc. Thus, it is astounding that the use of integrative approaches to address the question of the ecotoxicological relevance of the disruption of endocrine and related reproductive functions is rate. As a consequence of this shortcoming, there is increasing demand both among scientists and politicians regarding more holistic approaches in the endocrine disruptor research.

Aim

This contribution aims to critically discuss current strategies and approaches as well as to identify alternative strategies in context with the environmental risk assessment of endocrine disruptors. This will be exemplified using an ecotoxicological study with bream (Abramis brama) that was conducted along a major European river, the Elbe.

Results and Discussion

Local bream (Abramis brama) populations collected along the river Elbe were characterized by different magnitudes and/or types of endocrine alterations. Although there is a relatively extensive data set available regarding its contamination with wide range of chemicals in the Elbe, it has not been possible to conclusively relate the observed endocrine effects to the exposure to individual compounds or mixtures of chemicals. However, during the gross morphological evaluations of the fish it was observed that at some locations a great number of the individuals caught were parasitized with the tapeworm Ligula intestinalis. Furthermore, statistical analysis revealed that a relatively great percentage of the variation of the biological endpoints observed both among individuals and sampling sites could be explained by the occurrence of this parasite. Overall, the findings of these studies indicate that there is a complex interaction not only among the exposure to chemicals and parasitism but also of both of these aspects with the occurrence of biological effects in fish.

Conclusions

The gaps in our current knowledge as well as the findings from the few studies available indicate, the there is a need to revise our current approaches to characterize and evaluate exposure scenarios regarding their potential to cause endocrine disruption in wild organisms. Given the complexity of most environmental exposure scenarios, involving multiple factors including anthropogenic and natural influences and their interactions, I therefore see the urgent need to initiate a discussion on more integrative approaches in this field in favor of true ‘ecotoxicological studies’ that integrate both ecology and toxicology.     

Predators choosing between patches with standing crop: the influence of switching rules and input types

Where prey arriving in a patch are not consumed immediately, they will accumulate. Predators are then presented with a prey density or standing crop that increases through further input, and decreases through the consumption by predators. Firstly, I show that the switching rule of predators has a significant influence on the expected predator equilibrium distribution in such a dynamic system. Three rules are compared; for all rules, analytical solutions are calculated (where possible). To test their plausibility for natural situations, predator distributions are simulated given the assumption that each predator obtains individual patch profitability estimates by using a common learning rule. As long as prey arrive in the patches in constant numbers per time unit, the first rule leads to input matching because predators stop switching when consumption in the two patches is equal. The other two rules, where predators continue to sample both patches even in the equilibrium state, lead to predator distributions where the more profitable patch is underused. The final equilibrium depends on the exact assumptions of the switching rule; however, it is independent of interference. But if the input delivered into a patch is a function of the current prey standing crop (for example in a reproducing prey population), predator and prey distributions will not reach an equilibrium in most cases: either standing crops increase indefinitely, or they approach zero, with all predators concentrating on the better patch. Only a small number of parameter sets show intermediate crops that are reasonably stable. With this input type, only up to 54% of the simulations reach the expected distribution. In a system with competition for dynamic standing crop, it is therefore essential to know the type of input and the switching-rule used by predators to be able to predict equilibrium predator distributions. Received: 17 March 1995/Accepted after revision: 5 November 1995     

Storage and metabolism of radioactively labeled pyrrolizidine alkaloids by butterflies and larvae of Mechanitis polymnia (Lepidoptera: Nymphalidae,Ithomiinae)

Summary. Tracer feeding studies with radioactively labeled pyrrolizidine alkaloids (PAs) were performed to attain experimental information about the specificity and mechanisms of uptake, metabolism and storage of PAs in the alkaloid sequestering ithomiine butterfly Mechanitis polymnia. Adult butterflies easily ingest the tracers offered dissolved in a saturated sugar solution. Feeding of [¹⁴C]rinderine (free base) confirmed that M. polymnia is well adapted to sequester and maintain PAs of the lycopsamine type. Approximately 80% of the ingested radioactivity can be recovered in methanol extracts of the butterflies over a period of at least 6 hours. Labeled rinderine is efficiently N-oxidized and transformed into a metabolite of still unknown structure. These two metabolites are formed in almost equal amounts and account for more than 90% of total radioactivity. After four hours the toxic free base is only detectable in traces. Radioactively labeled senecioylretronecine (free base), a PA that often accompanies PAs of the lycopsamine type in plants, is metabolized in a different manner. The toxic free base disappeared as fast as the tertiary rinderine, but the final products which accumulated in a stable ratio after 12 hours were mainly two polar metabolites of unknown structure; senecioylretronecine N-oxide accounts for less than 10% of total PAs. Labeled senecionine a macrocyclic PA, which never has been found in wild caught M. polymnia is only slowly N-oxidized. In females ca 50% of the ingested senecionine is still present as free base after 24 hours, whereas under the same conditions in males this percentage is only ca 20%. This difference in N-oxidation was the only significant sex-specific difference observed in various experiments. Larvae of M. polymnia which feed on Solanum tabacifolium, a plant that does not contain PAs, are able to sequester and partly N-oxidize labeled senecioylretronecine and senecionine. However, the storage is not very efficient; with the two tracers less than 5% of radioactivity remained in the bodies after 24 hours. Received 19 October 1999; accepted 24 November 1999     

The Baltic haline conveyor belt or the overturning circulation and mixing in the Baltic

A study of the water-mass circulation of the Baltic has been undertaken by making use of a three dimensional Baltic Sea model simulation. The saline water from the North Atlantic is traced through the Danish Sounds into the Baltic where it upwells and mixes with the fresh water inflow from the rivers forming a Baltic haline conveyor belt. The mixing of the saline water from the Great Belt and Oresund with the fresh water is investigated making use of overturning stream functions and Lagrangian trajectories. The overturning stream function was calculated as a function of four different vertical coordinates (depth, salinity, temperature and density) in order to understand the path of the water and where it upwells and mixes. Evidence of a fictive depth overturning cell similar to the Deacon Cell in the Southern Ocean was found in the Baltic proper corresponding to the gyre circulation around Gotland, which vanishes when the overturning stream function is projected on density layers. A Lagrangian trajectory study was performed to obtain a better view of the circulation and mixing of the saline and fresh waters. The residence time of the water masses in the Baltic is calculated to be 26-29 years and the Lagrangian dispersion reaches basin saturation after 5 years.