Microcontroller PIC 16F877A standard based on solar cooker using PV—evacuated tubes with an extension of heat integrated energy system

Environmental Science and Pollution Research - The unavailability of sunlight during nighttime and cloudy weather condition has limited the usage of solar cookers throughout the day. This study...     

Identification of a novel PCB source through analysis of 209 PCB congeners by US EPA modified method 1668

PCDD/Fs and PCBs in surface waters and effluent waste streams flowing into New York/New Jersey Harbor were sampled by large volume filtration and solid phase extraction (XAD-2). Passive hexane samplers were employed in sewer trackdown. Extraction media were analyzed for 2,3,7,8 substituted PCDD/Fs and all 209 PCB congeners. The non-Aroclor PCB congener, 3,3^′-DiCB, was ubiquitous in the harbor and was found to be associated with pigment manufacture. Knowledge of inadvertent synthesis of non-Aroclor PCBs is not new but its magnitude and the generation of congeners with dioxin-like properties from this process is novel.     

Detecting an orientation component in animal paths when the preferred direction is individual-dependent

An orientation component leads to directionally biased paths, with major consequences in animal population redistribution. Classical orientation analyses, which focus on the overall direction of motion, are useless for detecting such a component when the preferred direction is not common to the whole population, but differs from one path to another. In-depth path analyses are required in this case. They consist of determining whether paths are more suitably represented as biased or unbiased random walks. The answer is not easy because most animals' paths show some forward persistence propensity that acts as a purely local directional bias and, hence, blurs the possible occurrence of an additional, consistent bias in a preferred direction. I highlight the key differences between biased and unbiased random walks and the different ways orientation mechanisms can generate a consistent directional bias. I then examine the strength and weakness of the available methods likely to detect it. Finally, I introduce a new procedure based on the backward evolution of the beeline distance, from the end of the path, which might correspond to a goal toward which the animal orients itself, to each of the animal's preceding locations. This new procedure proves to be very efficient, as it requires only a small sample of short paths for detecting a possible orientation component.     

Building resilience and adaptation to manage Arctic change

Unprecedented global changes caused by human actions challenge society's ability to sustain the desirable features of our planet. This requires proactive management of change to foster both resilience (sustaining those attributes that are important to society in the face of change) and adaptation (developing new socioecological configurations that function effectively under new conditions). The Arctic may be one of the last remaining opportunities to plan for change in a spatially extensive region where many of the ancestral ecological and social processes and feedbacks are still intact. If the feasibility of this strategy can be demonstrated in the Arctic, our improved understanding of the dynamics of change can be applied to regions with greater human modification. Conditions may now be ideal to implement policies to manage Arctic change because recent studies provide the essential scientific understanding, appropriate international institutions are in place, and Arctic nations have the wealth to institute necessary changes, if they choose to do so.     

The impact of seasonal variations in DOC arising from a moorland peat catchment on coagulation with iron and aluminium salts

Natural organic matter (NOM) is one of the main sources of environmental pollution to drinking water supplies in much of the UK and the US. Whilst traditional treatment with trivalent coagulants has proven a successful strategy in the past, operational problems are now being reported during periods of elevated organic levels in the water. Characterisation of the pollutants in terms of polarity, molecular weight and charge, provides a method to understand the impact of the observed temporal and spatial variations in terms of a mechanistic parameter relevant to the treatment processes. Results from this study demonstrate that it is not simply the increased organic concentration, but also the change in NOM composition and character, which influences the impact on the treatment processes. Consequently, monitoring of these parameters provides an insight into how to manage the impact caused by environmental changes to the catchments.     

A commentary on recent water safety initiatives in the context of water utility risk management

Over the last decade, suppliers of drinking water have recognised the limitations of relying solely on end-product monitoring to ensure safe water quality and have sought to reinforce their approach by adopting preventative strategies where risks are proactively identified, assessed and managed. This is leading to the development of water safety plans; structured 'route maps' for managing risks to water supply, from catchment to consumer taps. This paper reviews the Hazard Analysis and Critical Control Point (HACCP) procedure on which many water safety plans are based and considers its appropriateness in the context of drinking water risk management. We examine water safety plans in a broad context, looking at a variety of monitoring, optimisation and risk management initiatives that can be taken to improve drinking water safety. These are cross-compared using a simple framework that facilitates an integrated approach to water safety. Finally, we look at how risk management practices are being integrated across water companies and how this is likely to affect the future development of water safety plans.     

Wildlife identified as major source of Escherichia coli in agriculturally dominated watersheds by BOX A1R-derived genetic fingerprints

The presence of Escherichia coli in recreational and potable waters is a major concern to the general public as elevated levels of E. coli suggest the presence of pathogenic bacteria and viruses. Unfortunately, traditional microbial techniques do not allow specific identification of the source of E. coli. This reduces the ability to target management practices that reduce bacterial contamination. In the Finger Lakes region of western New York, USA, wildlife resides in relatively high densities on watersheds dominated by people and dairy farms, and as a result, the sources of fecal degradation of potable and recreational waters are often unknown. In the Conesus Lake watershed, the sources of microbial contamination were assessed using Rep-PCR molecular tools, a method of amplifying repetitive DNA sequences found throughout the E. coli genome to produce distinct fingerprints for a given ecotype. Molecular fingerprints of E. coli isolated from regional populations of cattle, humans, geese and deer were compared to E. coli isolated from stream water samples. Canonical discriminant function analysis indicated that the DNA fingerprints of the original source group isolates were correctly predicted 90.2% of the time. Since land use in the sub-watersheds was dominated by dairy and cash crop farms, it was expected that the majority of E. coli isolated would be identified as cows; however, an unexpectedly high percentage of isolates were identified as wildlife (geese and deer). Geese were the dominant source of E. coli (44.7-73.7% of the total sources) in four sub-watersheds followed by cows (10.5-21.1%), deer (10.5-18.4%), humans (5.3-12.9%) and unidentifiable sources (0.0-11.8%). Management practices intended to decrease the number of cattle or the amount of manure spread in a sub-watershed were reflected in a decrease of E. coli ecotypes associated with dairy cows.     

Understanding transitions in farming systems and their effects on livestock rearing and smallholder livelihoods in Telangana,India

Increasing food demands are causing rapid transitions in farming systems, often involving intensified land and resource use. While transitioning has benefits regarding poverty alleviation and food outputs, it also causes environmental and social issues over time. This study aims to understand the transitions in farming systems in a region in Telangana, from 1997 to 2015, and their effect on livestock rearing and smallholder livelihoods. We also examine the impact of the transitions on lower caste groups and women in particular. We collected data using a combination of methods, i.e., a household survey, focus group discussions, and secondary data sources, to build a comprehensive picture of the transitions in the region. We found that subsistence mixed farming systems transitioned to market-orientated specialized systems over a short time span. As the transition process gained momentum, households either intensified their production or got marginalized. Technological interventions, development programs with integrated approaches, and market demand for certain agricultural produce triggered increased regional production but also led to the scarcity of water, land, and labor. The transitions marginalized some of the households, changed the role of livestock in farming, and have been inclusive of both lower caste groups and women in terms of increased ownership of large ruminants and access to technologies. However, for women specifically, further increase in workload in the context of farming is also found.     

Bird distributions relative to remotely sensed habitats in Great Britain: towards a framework for national modelling

This paper develops a comprehensive and objective picture of bird distributions relative to habitats across Britain. Bird species presence/absence data from an extensive field survey and habitat data from the remotely sensed UK Land Cover Map 2000 were analysed in 36,920 tetrads (2 kmx2 km) across Britain (a 65% sample of Britain's c. 240,000 km2). Cluster analysis linked birds to generalised landscapes based on distinctive habitat assemblages. Maps of the clusters showed strong regional patterns associated with the habitat assemblages. Cluster centroid coordinates for each bird species and each habitat were combined across clusters to derive individualised bird-habitat preference indices and examine the importance of individual habitats for each bird species. Even rare species and scarce habitats showed successful linkages. Results were assessed against published accounts of bird-habitat relations. Objective corroboration strongly supported the associations. Relatively scarce coastal and wetland habitats proved particularly important for many birds. However, extensive arable farmland and woodland habitats were also favoured by many species, despite reported declines in bird numbers in these habitats. The fact that habitat-specialists do not or cannot move habitat is perhaps a reason for declining numbers where habitats have become unsuitable. This study showed that there are unifying principles determining bird-habitat relations which apply and can be quantified at the national scale, and which corroborate and complement the cumulative knowledge of many and varied surveys and ecological studies. This 'generality' suggests that we may be able, reliably and objectively, to integrate and scale up such disparate studies to the national scale, using this generalised framework. It also suggests the potential for a landscape ecology approach to bird-habitat analyses. Such developments will be important steps in building models to develop and test the sustainable management of landscapes for birds.     

Predicting the Vulnerability of Tropical Reef Fishes to Exploitation with Phylogenies and Life Histories

Abstract: Fishing has led to local extirpations of reef fishes. For conservation and management purposes, it is important to identify all those species that are vulnerable to fishing, but this cannot be done using a priori assessments or by describing trends in abundance because the necessary scientific resources are not available. Thus the predictions of vulnerability that provide the basis for conservation action will have to be made with existing data or data that can be acquired rapidly before further extirpations occur. The life histories of species may determine their responses to exploitation, and we describe how an easily measured parameter, maximum observed size, is related to population trends of exploited fishes on coral reefs. Using a phylogenetic comparative approach, we demonstrated that species of grouper (Epinephelinae), snapper (Lutjanidae), and parrotfish (Scaridae) that decreased in abundance more than their nearest phylogenetic relative had greater maximum size. Our results suggest that one can predict the vulnerability of reef fishes to exploitation based on responses of their relatives. The quality of the prediction was good for the intensively fished groupers and snappers but poor for the lightly fished parrotfishes. Our approach may help proactive conservationists and fishery managers identify and conserve vulnerable species in new, developing, or lightly exploited fisheries, thereby reducing their reliance on reactive management methods.