Analysis of a rural water supply project in three communities in Mali: Participation and sustainability

This paper presents a qualitative assessment of the participatory water management strategies implemented at the community level in rural Mali through a water supply project — The West Africa Water Initiative (WAWI) — coordinated by World Vision International, a non‐governmental and humanitarian organization. Data for the study were generated through a combination of primary and secondary sources in three villages. Results of the study indicate that while community‐based rural water supply is a positive step in responding to the needs of rural Malians, the installation of boreholes with hand pumps informed merely by consultative participatory approaches and limited extension involvement will not necessarily proffer sustainable rural water supply in the region. A “platform” approach to rural water supply management that can mobilize the assets and insights of different social actors to influence decision making at all stages, including the design and choice‐of‐technology stages, in water supply interventions is instead advocated.     

The effects of higher energy prices and declining ore quality: Copper—aluminium substitution and recycling in the USA

An econometric model of the US copper and aluminium industries is simulated to evaluate the impact that higher energy prices and declining ore quality will have on copper–aluminium substitution and recycling in the USA in the next decade. The unique features of the model described here include the calculation of elasticities of substitution between copper and aluminium from the production functions of the using sectors, the use of statistical (not engineering) cost functions for both the primary and the secondary industries, and the explicit consideration of ore- quality deterioration as primary production progresses.     

Subsurface patch of a dinoflagellate (Ceratium tripos) off Southern California: Patch length,growth rate,associated vertically migrating species

Ceratium tripos dominated a multi-species dinoflagellate patch in the sub-surface chlorophyll maximum in August 1978 on the Southern California shelf. The specific growth rate () ofC. tripos averaged 0.25 d^-1. Patch length was about 45 km along the shelf. Several members of the subsurface dinoflagellate assemblage were also present in surface samples, but only during the daytime. These apparent vertical migrators includedProrocentrum micans, C. furca, Gonyaulax polyedra and other less common forms. The growth ofC. tripos in the California patch is compared with that in aC. tripos patch off New York in 1976.     

Modeling pesticide volatilization from turf

Pesticide volatilization models are typically based on equilibrium partitioning of the chemical into solid, liquid, and gaseous phases in the soil environment. In turf systems direct vaporization from vegetation surfaces is a more likely source, and it is difficult to apply equilibrium methods to plant material due to the uncertainties of solid-liquid-gas partitioning. An alternative approach is to assume that pesticide volatilization is governed by the same processes that affect water evaporation. A model was developed in which evapotranspiration values, as determined by the Penman equation, were adjusted to chemical vaporization using ratios of water and chemical saturated vapor pressures and latent heats of vaporization. The model also assumes first-order degradation of pesticide on turf vegetation over time. The model was tested by comparisons of predictions with measurements of volatilization for eight pesticides measured during 3 to 7 d in 11 field experiments. Measured volatilization fluxes ranged from 0.1 to 22% of applied chemical. Pesticides were divided into two groups based on saturated vapor pressures and organic C partition coefficients. One pesticide was selected from each group to calibrate the model's volatilization constant for the group, and the remaining pesticides were used for model testing. Testing results indicated that the model provides relatively conservative estimates of pesticide volatilization. Predicted mean losses exceeded observations by 20%, and the model explained 67% of the observed variation in volatilization fluxes. The model was most accurate for those chemicals that exhibited the largest volatilization losses.     

Benefits of Collaborative Learning for Environmental Management: Applying the Integrated Systems for Knowledge Management Approach to Support Animal Pest Control

Resource management issues continually change over time in response to coevolving social, economic, and ecological systems. Under these conditions adaptive management, or “learning by doing,” offers an opportunity for more proactive and collaborative approaches to resolving environmental problems. In turn, this will require the implementation of learning-based extension approaches alongside more traditional linear technology transfer approaches within the area of environmental extension. In this paper the Integrated Systems for Knowledge Management (ISKM) approach is presented to illustrate how such learning-based approaches can be used to help communities develop, apply, and refine technical information within a larger context of shared understanding. To outline how this works in practice, we use a case study involving pest management. Particular attention is paid to the issues that emerge as a result of multiple stakeholder involvement within environmental problem situations. Finally, the potential role of the Internet in supporting and disseminating the experience gained through ongoing adaptive management processes is examined.     

Analysis of the role of waste minimisation clubs in reducing industrial water demand in the UK

As a result of the UK Government's waste policy, which increasingly encourages sustainable development, and the realisation that water in the UK cannot be treated as an unlimited resource, there is growing interest in reducing the demand for water by industry. A series of industrial waste minimisation clubs have been set up within the country. This paper identifies the effectiveness of these clubs in reducing the demand for water. An overview of some of the clubs show how there is a major discrepancy between potential and implemented water savings, whilst a more detailed analysis of three specific examples show how water demand and cost to the company can be reduced, with the project paying for itself within around 1 year. It appears that companies are able to reduce water consumption by approximately 30%. If this level of saving was taken up by the entire industrial sector in England and Wales, water consumption could be reduced by approximately 1500 Ml/day. This reduction would be more significant in regions of lower rainfall, for example East Anglia and Southeast England.     

A review of source tracking techniques for fine sediment within a catchment

Excessive transport of fine sediment, and its associated pollutants, can cause detrimental impacts in aquatic environments. It is therefore important to perform accurate sediment source apportionment to identify hot spots of soil erosion. Various tracers have been adopted, often in combination, to identify sediment source type and its spatial origin; these include fallout radionuclides, geochemical tracers, mineral magnetic properties and bulk and compound-specific stable isotopes. In this review, the applicability of these techniques to particular settings and their advantages and limitations are reviewed. By synthesizing existing approaches, that make use of multiple tracers in combination with measured changes of channel geomorphological attributes, an integrated analysis of tracer profiles in deposited sediments in lakes and reservoirs can be made. Through a multi-scale approach for fine sediment tracking, temporal changes in soil erosion and sediment load can be reconstructed and the consequences of changing catchment practices evaluated. We recommend that long-term, as well as short-term, monitoring of riverine fine sediment and corresponding surface and subsurface sources at nested sites within a catchment are essential. Such monitoring will inform the development and validation of models for predicting dynamics of fine sediment transport as a function of hydro-climatic and geomorphological controls. We highlight that the need for monitoring is particularly important for hilly catchments with complex and changing land use. We recommend that research should be prioritized for sloping farmland-dominated catchments.