Environmental change in the Sahel: reconciling contrasting evidence and interpretations

The Sahel has been the object of intensive international research since the drought of the early 1970s. A considerable part of the research has focused on environmental change in general and land degradation, land cover change and climate change in particular. Rich and diverse insights from many different scientific disciplines about these three domains have been put forward. One intriguing feature is that an agreement on the overall trends of environmental change does not appear to emerge: questions such as whether the Sahel is greening, cropland is encroaching on rangelands, drought persists remain contested in the scientific literature, and arguments are supported by contrasting empirical evidence. The paper explores the generic reasons behind this situation in a systematic manner. We distinguish between divergences in interpretations emerging from (1) conceptualizations, definitions and choice of indicators, (2) biases, for example, related to selection of study sites, methodological choices, measurement accuracy, perceptions among interlocutors, and selection of temporal and spatial scales of analysis. The analysis of the root causes for different interpretations suggests that differences in findings could often be considered as complementary insights rather than mutually exclusive. This will have implications for the ways in which scientific results can be expected to support regional environmental policies and contribute to knowledge production.     

Haematological changes in fluorotic adults and children in fluoride endemic regions of Gaya district,Bihar, India

Groundwater used for drinking and cooking was analysed for fluoride (F), and health surveys were conducted in Bodh Gaya, Amas and Bankebazaar blocks of the Gaya district, Bihar, India. Amas and Bankebazaar blocks were F endemic areas with mean F = 2.36 ± 0.23 mg/L (N = 27). Bodh Gaya was considered as control area with mean F = 0.59 ± 0.03 mg/L (N = 11). Health survey showed that more than 50 % of adults and more than 55 % of children had complaints of gastro-intestinal (GI) disturbances in the F endemic areas, while less than 20 % of adults and less than 10 % of children complained of GI problems in the control areas. Haematological analyses were conducted on age- and sex-matched fluorotic subjects (N = 93) of F endemic areas, and non-fluorotic subjects (N = 52) of control area showed lowered haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, and mean corpuscular haemoglobin concentration in the fluorotic subjects, suggesting the occurrence of anaemia in the fluorotic subjects.     

Influence of Processing Conditions on Morphological,Thermal and Degradative Behavior of Nanocomposites Based on Plasticized Poly(3-hydroxybutyrate) and Organo-Modified Clay

The effect of processing conditions (casting and extrusion) and plasticization on the disintegrability in compost of organically modified clay poly(3-hydroxybutyrate) nanocomposites was studied. Tributylhexadecylphosphonium bromide (TBHP) was used as organic modifier. As revealed by WAXS and TEM observations, intercalated nanobiocomposites with clay stacks and some individually dispersed platelets were obtained. The melting temperature of the neat PHB diminished with the addition of plasticizer, thus broadening the processing window. Biodegradation test revealed that while the clay slows down the degradation rate, the plasticizer increases the degradation of the samples, reaching a similar final percentage of disintegrability when both plasticizer and clay were added in the formulation.     

Validation of an Automated Multiunit Composting System

Biodegradable packaging has high potential to help solve the crisis of non-biodegradable plastic waste causing an increase in the footprint of landfills. However, more research needs to be executed to develop a larger assortment of biodegradable plastics for numerous applications and to make them more economical to manufacture. This paper discusses the design and validation of an automated composting system (AMUCS) that fits the requirements of the American Society for Testing and Materials (ASTM) 5338-11 standard. The results of the experiments show that the AMUCS was able to create and maintain the conditions for biodegradation of biodegradable polymers in compost using microcrystalline cellulose. The biodegradation caused by the composting environment was observed visually with the naked eye and on the micro scale with an environmental scanning electron microscope. The magnitude of biodegradation was measured by calculating the carbon metabolized from the samples. The carbon metabolized from the three compost replicates was consistent and linear, and there was only an 8 % difference between the non-biodegradable low density polyethylene and the compost. For the biodegradation study according to ASTM D 5338-11, the experiment was validated with the use of cellulose as a reference material. Under controlled composting conditions, the mineralization of microcrystalline cellulose yielded 72.05 %, which is slightly higher than the 70 % mineralization requirement.     

Factors influencing wing size and body weight variation in the western honeybee

The patterns of wing size and body weight variation have been studied in worker bees, queens, and drones of the western honeybee. The influences of physiological states and ecological situations on the weight of the body and its parts and on the filling of the digestive tract have been analyzed. The results show that the differences in body weight between worker bees, queens, and drones do not correspond to differences in wing size between them. It is noted that worker bees, with their relatively small but strongly varying body weight, have acquired relatively large wings in the course of species phylogeny, a process accompanied by functional and morphophysiological differentiation of the members of bee families.     

Sensitivity of streamflow and microbial water quality to future climate and land use change in the West of Ireland

Regional Environmental Change - This study applied catchment modeling to examine the potential effects of climate change and future land management variations on streamflow and microbial transport...