Third European Chemistry Congress “Resources and Environment”

Environmental Science and Pollution Research -     

Assessing the impacts of sustainable development projects in the Amazon: the DURAMAZ experiment

Since 1992, a boom of “sustainable development projects” has been registered in the Brazilian Amazon, turning it into a kind of open-air laboratory for sustainability. But their real impacts remain unclear, especially because of inadequate evaluation tools. A new device is therefore needed to unveil the inner mechanisms of development aid despite the difficulties linked with the diversity of contexts or the heterogeneity in the relevant parameters. Those are the challenges we met when we engaged in comparing the impacts of sustainable development programs in 13 sites throughout the Brazilian Amazon in order to identify determining factors of sustainability. To achieve our objective, we conceived an indicator system based on the results of intensive fieldwork, including social, economic, environmental, and biographical issues. Our results show that the most prominent problem of sustainability—evaluation of effectiveness—has not been tackled; life conditions and environmental preservation continue to appear antagonistic. At the same time, variability appears among outwardly coherent social groups, showing that a case-to-case approach is definitely indispensable and confirming the need to go “beyond panaceas” to find resolutions. This article successively addresses three points. First, we present the starting point of our research, or how the Amazon region was turned into a laboratory for sustainability and how our research project aimed at analyzing the consequences of this trend. Second, we discuss how available indicator systems fail to respond to the need for a multidimensional evaluation at the local level and, therefore, how we constituted our own analytical tool. Third, we focus on some results that can be derived from our system, especially in terms of identifying key factors needed to achieve sustainability in the Amazon.     

Justice in development? An analysis of water interventions in the rural South

This paper explores a fruitful convergence between the distributive and procedural dimensions of environmental justice theory and current debates in the field of development studies over capitals and capabilities, institutions, and discourse formation to shed new light on natural resource management projects in the developing world. Specifically, we document the planning and implementation of two types of water interventions in two contrasting regions: watershed development programmes in northeast India and small reservoirs in sub‐Saharan West Africa. We find that there is a contradiction between the inherently political nature of water interventions and the fact that such projects remain grounded in apolitical, technical and managerial narratives. In contrast to the new semantic of development, this depoliticization results in the near absence of attention paid to procedural (participation and empowerment) and distributive (equity) justice concerns and in local actors having to revert to covert ways to achieve their ends. A constructive dialogue between development studies and environmental justice scholars can offer a fresh look on the society‐environment nexus in the developing world.     

First approach for the identification of sardine populations <Emphasis Type="Italic">Sardina pilchardus</Emphasis> (Walbaum 1792) in the Moroccan Atlantic by allozymes

This study aimed at contributing to the identification of the sardine populations in the Moroccan Atlantic. The approach used is enzymes electrophoresis (allozymic marker analysis). The analysis was conducted in seven stations (251 individuals analysed). Two enzymes were tested (LDH* and SOD*). Only the SOD* was polymorphic and highly informative. Statistical analysis results showed heterogeneity between samples. Homogeneous population was identified in the south, from Tarfaya to Dakhla (~28°–24°N). The sampling from Safi (~32°N) seems to come from a differentiated population. The Agadir (~30°N) population would overlap the previous ones. The population identified offshore of Larache (~35°N) would be similar to the population located south of Portugal (~37°N).     

Modeling the binding of triazine herbicides to humic substances using capillary electrophoresis

The binding of 4 s-triazines herbicides and metabolites, ameline, hydroxyatrazine, atraton, and ametryn to 12 structurally different humic substances was studied by affinity capillary electrophoresis. Binding data were confronted to the structural data of humic acids obtained from spectrometric measurements (UV-Vis, FT/IR, NMR), elemental analysis and potentiometric titration. The results obtained with principal component analysis and partial least square analysis clearly show the importance of carboxylic acidity and aromaticity of the humic ligands in relation to the partial positive charge and relative hydrophobicity of the pesticides.     

Serum polychlorinated biphenyl and organochlorine insecticide concentrations in a Faroese birth cohort

A prospective birth cohort of 1022 participants was established in the Faroe Islands over a 21-month period during 1986-1987. We collected questionnaire data on potential persistent organic pollutant (POP) concentration predictors, such as duration of breastfeeding and blubber consumption. To assess the participants' exposure from in utero to 14 years of age to polychlorinated biphenyls (PCBs) and the insecticide p,p'-DDT and its primary degradate p,p'-DDE, we measured 37 PCB congeners and pesticides in 316 umbilical cord samples taken from participants at birth, in 124 serum samples collected from participants at approximately 7 years of age, and in 795 serum samples collected from participants at 14 years of age. Measurements of higher chlorination PCB congeners made on individuals' serum samples collected at 7 years and 14 years were highly correlated (typically r > 0.5, p > 0.01), although their concentrations at 7 years were generally two to three times higher than at 14 years. Similarly, umbilical cord PCB concentrations were correlated with PCB concentrations in both 7- and 14-year serum samples. Sex-specific differences in higher chlorination PCB and p,p'-DDE concentrations were found at 14 years but not at 7 years, although a sex interaction with blubber consumption and nursing duration was observed at both ages. Both duration of breastfeeding and consumption of blubber were significant predictors of serum summationPCB concentrations at 7 and 14 years. Multivariate analyses showed that breastfeeding duration was the primary contributor to serum summationPCB concentrations at 7 years, and blubber consumption was the primary contributor at 14 years. These data suggest that infant exposures from breastfeeding were sufficiently large so that continued exposures to PCBs, p,p'-DDT, and p,p'-DDE through the diet have not fully diluted their contribution to the summationPCB and p,p'-DDE body burden of the children.     

Detection of advected, reacting redox fronts from self-potential measurements

We report on an experiment aimed at testing the use of self-potential measurements to monitor the motion and mixing of redox reactants advected through a well-controlled, laboratory-scale, artificial aquifer system. A rectangular, plastic tank was filled up with water-saturated sand and an array of unpolarizable electrodes was installed in the sand body. A nearly uniform, steady-state flow was established by tilting the tank and controlling the water level in reservoirs at both ends. Then, we simultaneously injected a known quantity of KMnO(4) and FeCl(2), respectively, into two separate compartments forming the upstream reservoir. We thus generated two abrupt fronts, one oxidizing and the other reducing, which subsequently travelled in parallel by advection through the sand body. The KMnO(4) and FeCl(2) solutions were in contact and reacted with each other in a region located along the median vertical plane parallel to the flow direction. During flow, the electrical potential differences between each electrode and a reference located in the downstream reservoir were recorded. In the unreacted FeCl(2) region the electric potential showed sudden variations successively occurring at increasing distances in the flow direction, associated with the passage of the FeCl(2) front. These signals essentially corresponded to the junction potential produced by the difference in ionic mobility of Fe(2+) and Cl(-). In the unreacted KMnO(4) region sharp signals, but with much smaller amplitudes, were also observed. Near the vertical median plane on the FeCl(2) side, we observed a second front associated with the spreading of the reaction zone. The shape and evolution of the reaction zone was largely controlled by the precipitation of Fe(OH)(3).     

Incorporating dormancy in dynamic microbial community models

Biogeochemical activity in natural and engineered systems depends on the abundances, functional capabilities and physiological states of the indigenous microorganisms. Typically, only a fraction of the microbial population is active at any given time. As environmental conditions change, previously active microorganisms may switch to an inactive or dormant state, while dormant ones may become active. Here, we present an extended modeling concept for the growth and decay of microorganisms that explicitly accounts for their ability to switch between active and dormant states. The equations describing the switching between physiological states are implemented into a biogeochemical reaction simulator. The model was used to reproduce published data from two laboratory experiments in which microorganisms were subjected to intermittent substrate supply or reactivated after a prolonged period of starvation. Parameter values obtained from the simulation of these experiments were used for subsequent sensitivity analyses and for the simulation of hypothetical scenarios. Results for hypothetical microbial communities consisting of two competing species exposed to periodic feeding imply that, under certain conditions, an effective dormancy-reactivation strategy may have a competitive advantage over a fast growth strategy. That is, organisms that can switch rapidly in response to fluctuations in external conditions may outcompete fast-growing organisms. Furthermore, certain combinations of growth and dormancy strategies may lead to the long-term coexistence of the two competing species. Overall, the simulated population dynamics show that dormancy is an important feature of microbial communities, which can lead to complex responses to environmental fluctuations.