Alkylphenol polyethoxylate removal in a pilot-scale reed bed and phenotypic characterization of the aerobic heterotrophic community.

The removal of the non-ionic surfactant Triton X-100, dosed at 30 and 300 mg/L in a pilot-scale subsurface horizontal flow reed bed, and the aerobic heterotrophic cultivable community associated with the roots and with the substrate gravel in both absence and presence of Triton X-100 were investigated. t-Octylphenol (OP) and its mono-, di- and tri-ethoxyl derivatives, among others, were found in the outlet. A mass balance allowed us to calculate that approximately 40% of the Triton X-100 metabolites OP and octylphenol polyethoxylate derivatives flowed out of the reed bed during the dosage and postdosage experiments. More aerobic heterotrophic microorganisms adhered to the roots than to the gravel. The appearance of new strains (Aeromonas, Flavobacterium, and Aquaspirillum) and the increased presence of others (Pseudomonas) during the dosage of Triton may be linked to the capacity of these bacteria to adapt to the presence of the surfactant or to use it as a nourishment.     

Detection of vegetation degradation on Swedish mountainous heaths at an early stage by image interpretation

Mountainous vegetation in general, and especially in subpolar regions, is sensitive, compared to vegetation in lowland areas, as mountainous vegetation has low resilience and low productivity. Mountainous areas have been perceived as being sensitive to mechanical damage. Quick methods with a high degree of accuracy are needed for the monitoring of mountainous areas and for planning the sustainable use of resources. The aim was i) to investigate if the dry dwarf shrub heath on hummocky moraine in the southern part of the mountains with a maritime climate and in open areas used for summer grazing, is susceptible to change; and ii) to test if high-resolution IKONOS-2 satellite data can, with a high degree of accuracy, be used for detection, and for quantification and mapping of erosion patches in montane vegetation. In which case, these data can substitute color infrared aerial photos for the early detection of changes. For the detection of changes, visual interpretations on high-quality printouts of IKONOS-2 satellite images from 2000 and of color infrared aerial photographs from 1975 were carried out and the results compared. Interpretations were verified in the field. The results show that for the period 1975-2000, erosion was in process on and around wind heaths, indicating that the wind heath and surrounding dry dwarf shrub heath in this landscape type of hummocky moraine are sensitive to mechanical damage by trampling and grazing, and thus susceptible to change. Most of the wind heaths and changes found were small (50-1000 m2). The results show that it is possible to detect, with good accuracy, detailed changes in the size and distribution of erosion patches and wind heaths by visual interpretation in single images of IKONOS-2 data. This implies that for monitoring these kinds of changes, these high-resolution (4 x 4 m pixel resolution) satellite data can substitute for color infrared aerial photographs.     

Public participation in water resources management: stakeholder voices on degree, scale, potential, and methods in future water management

The European Water Framework Directive puts strong emphasis on stakeholder and public participation in water management. Several practical questions regarding who should be involved, why, when, and how still remain unanswered. This paper investigates stakeholders' own experiences and views of increased public participation in water management. The article also explores the potential for increasing levels of participation by forming catchment committees with representation from stakeholder groups and through the use of various practical methods for participation. For both these aspects of participation, the views, expectations, and apprehensions of different stakeholder groups involved in nutrient loss management are investigated. Stakeholder opinions were collected by inviting representatives from five stakeholder groups within the R?nne? catchment in southern Sweden to a catchment dialog process.     

Evaluation of sequentially-coupled POP fluxes estimated from simultaneous measurements in multiple compartments of an air-water-sediment system

Bulk atmospheric deposition fluxes, air-water exchange fluxes, particle settling fluxes out of the upper water column, sediment trap fluxes in deep waters, and sediment burial fluxes of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in the Koster Fjord, eastern Skagerak, on the Swedish west coast. The aim of the study was to compare the magnitude and direction of the compound fluxes in the system in order to diagnose key fate processes. The PCB and PAH fluxes via net atmospheric deposition, settling particles out of the surface and through deep waters, as well as into the accreting underlying sediments were shown to be remarkably similar, agreeing within a factor of a few for any given target compound. Fluxes of all PCB and PAH target compounds remained fairly constant with water column depth. Thus there was no evidence for net desorption from sinking particles. The net unidirectional and near balancing of vertical fluxes suggests a net transport of PCBs and PAHs from the atmosphere to the continental shelf sediments in the Koster Fjord, which is consistent with the hypothesis that the shelf sediments are important sinks for these compounds.     

Trypsin inhibitor,antioxidant and antimicrobial activities as well as chemical composition of potato sprouts originating from yellow- and colored-fleshed varieties

Abstract

Potato sprouts could be a valuable resource of phytochemicals such as secondary plant metabolites, potential antioxidants and nutritive compounds. In this work, potato sprout extracts of five varieties were examined; they differed in major glycoalkaloid content, trypsin inhibitor activity, total polyphenol content and antioxidant activity, as well as in antimicrobial activity against Gram?+?and G???bacteria, and yeast. Sprouts of colored-fleshed tubers were characterized by higher trypsin inhibitor activity than sprouts of yellow potatoes. The strongest microorganism growth inhibition effect was observed for macerate with sprouts from the purple-fleshed Blaue Annelise variety against B. subtilis, whereas C. albicans yeasts were sensitive to macerates with sprouts from purple-fleshed Blue Congo and yellow-fleshed Vineta potato varieties.     

Ozone dynamics and deposition processes at a deforested site in the Amazon basin

The goal of this study is to investigate the impact of deforestation on ozone dynamics and deposition in the Brazilian Amazon basin. This goal is accomplished through i) analyses of ozone levels and deposition rates at a deforested site during the rainy season; and ii) comparisons of these data with similar information derived at a forest. At the pasture site maximum ozone mixing ratios reach 20 parts per billion on a volume basis (ppbv) but about 6 ppbv prevail over the forest. Maximum ozone deposition velocities for pastures can reach 0.7 cm s-1, which is about threefold lower than values derived for forests. Combining ozone abundance and deposition velocities, pasture maximum ozone fluxes reach approximately 0.2 microgram (ozone) m-2 s-1. This flux represents approximately 70% of the deposition rates measured over the forest. Hence, this study suggests that conversion of rainforests to pastures could lead to a net reduction (30%) in the ozone sink in the Amazon.     

Removal of the herbicide amitrole from water by anodic oxidation and electro-Fenton

Here we demonstrate that an aqueous solution of the herbicide amitrole can be completely depolluted at pH 3.0 by anodic oxidation and electro-Fenton process. Anodic oxidation gives faster degradation with a boron-doped diamond anode than with a Pt anode. Electro-Fenton with a Pt anode and 1 mmol l ^–1 Fe²⁺ as catalyst yields the quickest depollution. Amitrole decay always follows a pseudo first-order reaction. NO₃^– and NH₄⁺ are accumulated in the medium during mineralization, although volatile N-products are also formed. These environmentally friendly electrochemical treatments could be applied to the remediation of wastewaters containing amitrole.     

The value of small size: loss of forest patches and ecological thresholds in southern Madagascar.

Many services generated by forest ecosystems provide essential support for human well-being. However, the vulnerability of these services to environmental change such as forest fragmentation are still poorly understood. We present spatial modeling of the generation of ecosystem services in a human-dominated landscape where forest habitat patches, protected by local taboos, are located in a matrix of cultivated land in southern Madagascar. Two ecosystem services dependent on the forest habitats were addressed: (1) crop pollination services by wild and semidomesticated bees (Apoidea), essential for local crop production of, for example, beans, and (2) seed dispersal services based on the presence of ring-tailed lemurs (Lemur catta). We studied the vulnerability of these ecosystem services to a plausible scenario of successive destruction of the smallest habitat patches. Our results indicate that, in spite of the fragmented nature of the landscape, the fraction of the landscape presently covered by both crop pollination and seed dispersal services is surprisingly high. It seems that the taboo system, though indirectly and unintentionally, contributes to upholding the generation of these services by protecting the forest patches. Both services are, however, predicted to be very vulnerable to the successive removal of small patches. For crop pollination, the rate of decrease in cover was significant even when only the smallest habitat patches were removed. The capacity for seed dispersal across the landscape displayed several thresholds with habitat patch removal. Our results suggest that, in order to maintain capacity for seed dispersal across the landscape and crop pollination cover in southern Androy, the geographical location of the remaining forest patches is more crucial than their size. We argue that in heavily fragmented production landscapes, small forest patches should increasingly be viewed as essential for maintaining ecosystem services, such as agricultural production, and also should be considered in the ongoing process of tripling the area of protected habitats in Madagascar.     

Sequestration of phorbol esters by aposematic larvae of Hyles euphorbiae (Lepidoptera: Sphingidae)?

Summary. The larvae of the hawkmoth species Hyles euphorbiae have a conspicuous aposematic colouration and show gregarious behaviour. It has thus been suggested that they sequester phorbol esters from their food plants which include different species of the genus Euphorbia (Euphorbiaceae) for chemical protection against predators. To test this hypothesis in more detail, we fed larvae an artificial diet with three doses of 12-tetradecanoyl-phorbol-13-acetate (TPA), then examined the faeces and the larval tissues, such as integument, haemolymph and gut of the caterpillars for the presence of TPA. In order to determine the ability of the larvae to detoxify phorbol esters, other larvae were directly injected with a TPA solution and analysed in the same manner. Our study indicates that the larvae of Hyles euphorbiae do not sequester phorbol esters. Upon oral application TPA was not found in the larval integument or the haemolymph. Instead, it was mostly metabolised (about 70–90%). Nevertheless, about 10-30% were retained and recovered in the faeces. The larvae were also able to metabolise and thus detoxify the phorbol ester when TPA was injected directly into the body. These hawkmoth caterpillars are relatively large and have a gut full of plant material, which they regurgitate into the direction of the predator when attacked in nature. Since phorbol esters are very potent toxins and irritants, we postulate that the gut content (and especially the plant slurry disgorged as regurgitant from the anterior gut) alone could be aversive for a potential predator, even if some metabolism has taken place. Thus, although H. euphorbiae caterpillars do not actively sequester phorbol esters, their aposematic colouration appears to be based on chemical defence through phorbol esters retained in the gut.