Little Egret (Egretta garzetta) as a bioindicator of trace element pollution in Tunisian aquatic ecosystems

The Little Egret, Egretta garzetta, has breeding colonies in the island of Chikly (in the lake of Tunis) and in Thyna saltpans (in the gulf of Gabès), two important Tunisian wetlands that are strongly affected by anthropogenic activity. Here, we used E. garzetta chick feathers for environmental monitoring of breeding grounds of this species. Since trophic ecology is fundamental when interpreting contamination levels, our approach combined both trace-element (Hg, Pb, Cd, and Se) and stable-isotope analysis of ??¹³C, ??¹⁵N, and ??³⁴S. Hg, Se, and ??¹⁵N levels were higher in specimens collected on Chikly than in Thyna. These observations highlight the degree of eutrophication of the lake of Tunis. Yellow-legged gulls (Larus michahellis) breeding in the same areas also feeds in the lake and attains similar concentrations of Hg and Se. In Thyna, egrets and gulls exploit distinct foraging habitats, as demonstrated by stable isotope analysis. The highest Hg and Se concentrations were found in Thyna. This result is consistent with greater exploitation of marine resources from the gulf of Gabès.     

Integrated approach for the quality assessment of freshwater resources in a vineyard area (South Portugal)

An integrated chemical and biological approach for the quality assessment of freshwater resources in a vineyard area of the ??Alentejo?? region (South Portugal) is presented. This includes analysis to 11 pesticide compounds and whole toxicity testing on algae and crustaceans. Simazine, terbuthylazine, terbutryn, desethylatrazine and chlorpyrifos were the most frequently detected pesticides in water collected from wells and drainage channels. Mixtures of up to three compounds in different qualitative combinations were also found. The quality standards for individual pesticides (0.1 ??g L^???1) and pesticides-total (0.5 ??g L^???1) were exceeded in some samples. However, their maximum concentrations were lower than the WHO guidelines, the USEPA health advisory values and the environmental quality standards for priority substances applicable to surface water. In five samples, the herbicides terbuthylazine and terbutryn and the insecticide chlorpyrifos did not pass the toxicity exposure ratio (TER) trigger values specified for aquatic organisms (algae, Daphnia and fish). Maximum toxic effects on Daphnia magna (100%) and Pseudokirchneriella subcapitata (82.56%) were determined in groundwater samples, while in surface water, no toxicity was observed. Concerning effects on Heterocypris incongruens in sediment samples collected at the drainage channels, mortality and growth inhibition values were below 38%. Pro-active management of the use of pesticides is recommended for implementing at the farm and catchment level to reduce inputs into ground- and surface water.     

Integrating in-situ, Landsat, and MODIS data for mapping in Southern African savannas: experiences of LCCS-based land-cover mapping in the Kalahari in Namibia

Integrated ecosystem assessment initiatives are important steps towards a global biodiversity observing system. Reliable earth observation data are key information for tracking biodiversity change on various scales. Regarding the establishment of standardized environmental observation systems, a key question is: What can be observed on each scale and how can land cover information be transferred? In this study, a land cover map from a dry semi-arid savanna ecosystem in Namibia was obtained based on the UN LCCS, in-situ data, and MODIS and Landsat satellite imagery. In situ botanical relevé samples were used as baseline data for the definition of a standardized LCCS legend. A standard LCCS code for savanna vegetation types is introduced. An object-oriented segmentation of Landsat imagery was used as intermediate stage for downscaling in-situ training data on a coarse MODIS resolution. MODIS time series metrics of the growing season 2004/2005 were used to classify Kalahari vegetation types using a tree-based ensemble classifier (Random Forest). The prevailing Kalahari vegetation types based on LCCS was open broadleaved deciduous shrubland with an herbaceous layer which differs from the class assignments of the global and regional land-cover maps. The separability analysis based on Bhattacharya distance measurements applied on two LCCS levels indicated a relationship of spectral mapping dependencies of annual MODIS time series features due to the thematic detail of the classification scheme. The analysis of LCCS classifiers showed an increased significance of life-form composition and soil conditions to the mapping accuracy. An overall accuracy of 92.48% was achieved. Woody plant associations proved to be most stable due to small omission and commission errors. The case study comprised a first suitability assessment of the LCCS classifier approach for a southern African savanna ecosystem.     

Sewing climate-resilient seeds: implementing climate change adaptation best practices in rural Cambodia

Multilateral support through programs like the Least Developed Countries Fund (LDCF) targets countries widely considered to be the most vulnerable to climate change. Cambodia is one of the six Asian LDCF recipients and with UNDP support is implementing the first adaptation project to arise from its National Adaptation Program of Action. Drawing on primary research conducted in August 2010 through interviews with key stakeholders, this article investigates the project for the likely benefits and challenges it will face in promoting institutional, infrastructural, and community resilience to climate change impacts. We find that the country??s ongoing decentralization reforms offer an effective opportunity to mainstream climate change planning into sub-national government operations, but that competing priorities for immediate investment in education, roads, and healthcare may prevent government officers from sustaining a focus on preventative adaptation measures. We conclude that through careful planning, water resources infrastructure and agricultural practices can be designed to withstand climate variability and avoid the need to replace or rehabilitate systems whose specifications were prematurely determined by international donors.     

Intercontinental chemical variation in the invasive ant Wasmannia auropunctata (Roger) (Hymenoptera Formicidae): a key to the invasive success of a tramp species

Unicoloniality emerges as a feature that characterizes successful invasive species. Its underlying mechanism is reduced intraspecific aggression while keeping interspecific competitiveness. To that effect, we present here a comparative behavioural and chemical study of the invasive ant Wasmannia auropunctata in parts of its native and introduced ranges. We tested the hypothesis that introduced populations (New Caledonia archipelago) have reduced intraspecific aggression relative to native populations (e.g., Ilhéus area, Brazil) and that this correlates with reduced variability in cuticular hydrocarbons (CHCs). As predicted, there was high intraspecific aggression in the Brazilian populations, but no intraspecific aggression among the New Caledonian populations. However, New Caledonian worker W. auropunctata remained highly aggressive towards ants of other invasive species. The chemical data corresponded with the behaviour. While CHCs of ants from the regions of Brazil diverged, the profiles of ants from various localities in New Caledonia showed high uniformity. We suggest that in New Caledonia W. auropunctata appears to behave as a single supercolony, whereas in its native range it acts as a multicolonial species. The uniformity of recognition cues in the New Caledonia ants may reflect a process whereby recognition alleles became fixed in the population, but may also be the consequence of a single introduction event and subsequent aggressive invasion of the ecosystem. Chemical uniformity coupled with low intraspecific but high interspecific aggression, lend credence to the latter hypothesis.     

OHP–APT 2002 gravity wave campaign: waves,turbulence and forecasts

In July 2002, a multi-sensor campaign was conducted in southern France to investigate the hypothesized connection between gravity waves and optical turbulence. A generalized scidar (GS) was mounted on the 1.93 m diameter telescope at l’Observatoire de Haute-Provence (OHP). The GS provides continuous profiles of optical turbulence with 300 m vertical resolution from telescope altitude up to 25 km. Thermosondes, which provide in situ measurement of optical turbulence by measuring temperature variance, were launched at the OHP site and at a site approximately 20 km west-northwest of OHP. Gravity wave activity was deduced from temperature and wind velocity measured by radiosondes, which are part of the thermosonde system. In this paper, gravity waves were analyzed using techniques for simple two-dimensional mountain waves, with only fair results. Mesoscale models were run at moderately high resolution for the period. The forecasts were analyzed for wave activity, and a post processor model was used to diagnose the optical turbulence. Mountain waves were evident in the forecast, but quantitative comparison showed the forecast to be inadequate in predicting wave strength. The forecast optical turbulence was in fair agreement with measurements with notable exceptions. This paper is declared a work of the U.S. Government and is not subject to copyright protection in the United States. The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. Presented at the Turbulence and Waves in Stably Stratified Atmospheric Shear Flows: Measurements, High Resolution Simulations and Numerical Prediction Challenges Conference, 13–15 September 2004, Lighthill Institute of Mathematical Sciences, University College London, London, UK.     

Environmental non-governmental organizations: key players in development in a changing climate��a case study of Mali

Developing countries are often most impacted by climate change. While the work of international environmental organizations has received considerable public and academic attention, local environmental non-governmental organizations (ENGOs) also play a key role in assisting local populations adapt to the changing environment and develop in a sustainable manner. Drawing on data from semi-structured interviews with rural Malians, and using a local ENGO [the Mali-Folkecenter Nyetaa (MFC)] as a case study, this paper begins by describing how rural Malians perceive climate change is impacting their lives, and how the MFC attempts to address these impacts with their programs in the communities. The paper then illustrates the unique advantages of local ENGOs, both in their holistic approach and their integration in the communities, to working with the local population, relative to the approach taken by larger NGOs in this field. It concludes by proposing that a key new avenue for the international community to meet its developmental and environmental goals could be to support the work of local ENGOs through, for example, existing carbon markets.