Environmental impacts of residual Municipal Solid Waste incineration: A comparison of 110 French incinerators using a life cycle approach

Incineration is the main option for residual Municipal Solid Waste treatment in France. This study compares the environmental performances of 110 French incinerators (i.e. 85% of the total number of plants currently in activity in France) in a Life Cycle Assessment perspective, considering 5 non-toxic impact categories: climate change, photochemical oxidant formation, particulate matter formation, terrestrial acidification and marine eutrophication. Mean, median and lower/upper impact potentials are determined considering the incineration of 1 tonne of French residual Municipal Solid Waste. The results highlight the relatively large variability of the impact potentials as a function of the plant technical performances. In particular, the climate change impact potential of the incineration of 1 tonne of waste ranges from a benefit of ?58 kg CO₂-eq to a relatively large burden of 408 kg CO₂-eq, with 294 kg CO₂-eq as the average impact. Two main plant-specific parameters drive the impact potentials regarding the 5 non-toxic impact categories under study: the energy recovery and delivery rate and the NO_x process-specific emissions. The variability of the impact potentials as a function of incinerator characteristics therefore calls for the use of site-specific data when required by the LCA goal and scope definition phase, in particular when the study focuses on a specific incinerator or on a local waste management plan, and when these data are available.     

Larval chemical defence and evolution of host shifts in Chrysomela leaf beetles

Summary. Larvae of Chrysomela leaf beetles release for defence volatile compounds belonging to various chemical families. This study focuses on the defensive strategy based on the esterification of isobutyric acid and 2-methylbutyric acid with a wide variety of alcohols taken up from the host plant. To date, only two species are known to produce these repellents C. interrupta, which is associated with Betulaceae and C. lapponica which occurs either on Betulaceae or Salicaceae.? In order to know if other species have developed this chemical defence and how the food plant influences the secretion of these toxins, we targeted by mass spectrometry the presence of iso- and 2-methylbutyric acids and esters of them in the defensive secretions of Chrysomela larvae exclusively associated with Betulaceae or Salicaceae. ?Screening analyses reveal that the synthesis of these compounds is a common character restricted to all the members belonging to the C. interrupta group sensu Brown (1956) regardless of the host-plant family. These results suggest that the biochemical mechanism leading to the synthesis of these compounds could be considered as a synapomorphy meaning that the group is probably monophyletic. ?Defensive secretions of the members of the interrupta group are quantitatively assayed for iso- and 2-methylbutyric acids and their (Z)-3-hexenyl esters. Results reveal a chemical plasticity developed by Chrysomela species associated with Salicaceae. The amounts of iso- and 2-methylbutyric acids derivatives and of salicylaldehyde in their larval secretions depend on the food plant and on its content in phenolglucosides. Received 5 October 1998; accepted 25 November 1998.     

Identification of odour sources in an industrial park from resident diaries statistics

A methodology based on social participation through the use of resident diaries was applied to evaluate the odour annoyance in the surroundings of an industrial park in Belgium during one year. The studied area covers about 8 km² and includes13 potential odour emitting facilities. The network involved 44 residents in the survey, among whom 19 were particularly considered for a detailed analysis. The questionnaire aimed at providing an odour rating twice-daily on a 6-level scale together with an odour type.The fact that the response rate corresponding to “no-odour” was high (79%) is particularly discussed. Some tests are proposed to check the plausibility of the answers, the coherence within clusters of residents and the individual performance of respondents to discriminate among odour ratings. The odour rose is presented as an attractive and visual tool, particularly suited in the case of multi-source areas, to map the different odour emissions, to point out the most worrying ones, to identify others creating less annoyance and possibly new unpredicted ones. The resident diary method has proven to be particularly useful, conjointly to other ones, to the case of multi-sources facilities in large areas, when the purpose is the assessment of the long-term evolution of odour annoyance.     

Strategies of homing behavior in the red squirrel,Tamiasciurus hudsonicus

Summary Seventeen red squirrels (Tamiasciurus hudsonicus) were displaced and released about 600 or 2000 m from their home site, and the routes they followed during several hours after release were recorded. The analysis of these routes shows that, in their first attempts to leave the release site area, the squirrels' orientation is non-random with respect to the home direction (Fig. 2a). However, after a few hundred meters in this initial direction, the animals tend to go back to the release site area, and then to perform a series of radial forays centered on the latter.The results suggest that, in the conditions of the experiment, the squirrels have some information on the direction, but not on the distance to the home site. Their behavior appears to be governed by two complementary (but occasionally conflicting) strategies, one being to use the directional information available, the other not to proceed further than a distance which corresponds to the distance normally covered in spontaneous exploratory trips. It is argued that this double strategy is appropriate for spontaneous homing trips consecutive to an exploratory foray.