Reticulated foam as a biomass support medium in the anaerobic digestion of an industrial wastewater.

This work reports the pilot-scale investigation of various anaerobic reactor systems treating a fruit washing wastewater. An open cell reticulated foam was used as a biomass support media (BSM). The foam pads (25 mm cubes) were randomly packed in the 2.5 m- 3 reactor with an unpacked section beneath the bed. Four general operational regimes were evaluated. These were: single and two stage operation, with and without effluent recycle. Performance was monitored throughout each run in terms of maximum COD loading rate and minimum attainable hydraulic retention time. Biomass concentrations, both within the media and freely suspended between the biomass support particles were measured on samples from each operating regime, their acetoclastic activity being determined in a laboratory test. A method was developed to ascertain whether a difference in biomass activity existed between the outside of an individual biomass support particle and at the centre of the particle, using a radioactively labelled substrate. It was concluded that a two stage system without recycle provided the best performance with respect to the the maximum attainable loading rate (11.6 kgCOD.m- 3 .day). This was approximately twice that for any of the other systems tested. The minimum hydraulic retention time corresponding to this loading was approximately 1.0 d. The superior performance of the two stage system without recycle was attributed to the increased acetoclastic populations brought about by the pre-acidified feed and the plug flow removal kinetics exhibited in reactors without recycle. Two stage systems produced higher levels of biomass in the reactor than their single stage counterparts and a large proportion of the total biomass inventory was present as suspended growth in systems without recycle. Tracer studies showed that the actual HRT was much less than that calculated from flow rate and reactor volume, indicating that large areas of the reactor were not accessible to the substrate. Experiments investigating activity gradients in the BSM indicated that a significant difference existed between the acetoclastic activity of biomass at the centre of a colonized particle and that on the surface. It may be concluded that substrate diffusional limitations played an important role in determining the performance of this type of biomass support. Electron microscope examination of BSP fragments gave little information other than the existence of both attached and suspended growth. Most of the bio mass was present as a dense fibrillar network

One Swallow Does Not Make a Summer: Siloes, Trade-Offs and Synergies in the Water-Energy-Food Nexus

Synergies are required to ensure coordination between UN agencies (on norms and indicators), Member States (on coherence of policy instruments) and consumers (on perceptions of safety and affordability of services) to advance the achievement of Sustainable Development Goal (SDG) target 6.3 which focusses on reuse of wastewater. In this paper we employ theoretical insights derived from an agent-based modeling approach to undertake a critical examination of the recent UN-WATER directive on SDG target 6.3 and advocate for an improved understanding of factors that determine whether and how effective wastewater reuse will be possible while accommodating for regional variation and institutional change. We demonstrate that by applying the Nexus approach it is feasible to overcome siloes by forging concepts of trade-offs and synergies to draw out coupled perspectives of bio-physical and institutional dimensions of water-energy-food interactions. By employing this proposition, the paper advocates for place-based observatories as a mechanism that can support valorization of data and methodological assumptions as a precursor to robust monitoring of the SDG's. The systematic use of literature reviews and expert opinion to develop and pilot-test composite indices via place-based observatories raises the prospect of a data light approach to monitoring SDGs; specifically, what are the merits of relying on extensive survey data compared to composite indices that while being amenable to supporting benchmarking and scenario analysis can provide the insight needed to inform decision-making and robust monitoring of global goals

Recommendations for building out mosquito-transmitted diseases in sub-Saharan Africa: the DELIVER mnemonic

In sub-Saharan Africa, most transmission of mosquito-transmitted diseases, such as malaria or dengue, occurs within or around houses. Preventing mosquito house entry and reducing mosquito production around the home would help reduce the transmission of these diseases. Based on recent research, we make key recommendations for reducing the threat of mosquito-transmitted diseases through changes to the built environment. The mnemonic, DELIVER, recommends the following best practices: (i) Doors should be screened, self-closing and without surrounding gaps; (ii) Eaves, the space between the wall and roof, should be closed or screened; (iii) houses should be Lifted above the ground; (iv) Insecticide-treated nets should be used when sleeping in houses at night; (v) houses should be Ventilated, with at least two large-screened windows to facilitate airflow; (vi) Environmental management should be conducted regularly inside and around the home; and (vii) Roofs should be solid, rather than thatch. DELIVER is a package of interventions to be used in combination for maximum impact. Simple changes to the built environment will reduce exposure to mosquito-transmitted diseases and help keep regions free from these diseases after elimination

Research agenda for preventing mosquito-transmitted diseases through improving the built environment in sub-Saharan Africa

Mosquito-transmitted diseases are a major threat to health in sub-Saharan Africa, but could be reduced through modifications to the built environment. Here we report findings from a major workshop held to identify the research gaps in this area, namely: (1) evidence of the health benefits to changes to the built environment, (2) understanding how mosquitoes enter buildings, (3) novel methods for reducing mosquito-house entry, (4) sustainable approaches for reducing mosquito habitats, (5) case studies of micro-financing for healthy homes and (6) methods for increasing scale-up. Multidisciplinary research is essential to build out mosquito-transmitted diseases, and not build them in

South Georgia and Gondwana's Pacific Margin: Lost in translation?

The geology of South Georgia has long been interpreted as the product of processes acting at the Pacific margin of Gondwana in Jurassic and earlier times. This placement requires 1600 km of translation of South Georgia to its present location, for half of which there is no evidence. Assuming this means that 800 km of the translation cannot have occurred, it requires that those processes acted at a location much further east, within the interior of Gondwana. One such location could have been at the southern edge of the Deseado Terrane, which collided and sutured with Gondwana in Carboniferous times. Later, in this location, South Georgia would have experienced shearing and extension during the earliest stages of breakup of the supercontinent, eventually to form part of the ensuing ocean's northern margin. These, or possibly more recent tectonic events on the lengthening northern margin of the Scotia Sea, led to the northward obduction of ophiolitic rocks onto the island. A history like this reduces South Georgia to a peripheral role in the paleoceanographic development of Drake Passage, and strengthens the case for Eocene connection between the Pacific and Atlantic oceans

Indicators linking health and sustainability in the post-2015 development agenda.

The UN-led discussion about the post-2015 sustainable development agenda provides an opportunity to develop indicators and targets that show the importance of health as a precondition for and an outcome of policies to promote sustainable development. Health as a precondition for development has received considerable attention in terms of achievement of health-related Millennium Development Goals (MDGs), addressing growing challenges of non-communicable diseases, and ensuring universal health coverage. Much less attention has been devoted to health as an outcome of sustainable development and to indicators that show both changes in exposure to health-related risks and progress towards environmental sustainability. We present a rationale and methods for the selection of health-related indicators to measure progress of post-2015 development goals in non-health sectors. The proposed indicators show the ancillary benefits to health and health equity (co-benefits) of sustainable development policies, particularly those to reduce greenhouse gas emissions and increase resilience to environmental change. We use illustrative examples from four thematic areas: cities, food and agriculture, energy, and water and sanitation. Embedding of a range of health-related indicators in the post-2015 goals can help to raise awareness of the probable health gains from sustainable development policies, thus making them more attractive to decision makers and more likely to be implemented than before

Mapping changes in housing in sub-Saharan Africa from 2000 to 2015

Access to adequate housing is a fundamental human right, essential to human security, nutrition and health, and a core objective of the United Nations Sustainable Development Goals1,2. Globally, the housing need is most acute in Africa, where the population will more than double by 2050. However, existing data on housing quality across Africa are limited primarily to urban areas and are mostly recorded at the national level. Here we quantify changes in housing in sub-Saharan Africa from 2000 to 2015 by combining national survey data within a geostatistical framework. We show a marked transformation of housing in urban and rural sub-Saharan Africa between 2000 and 2015, with the prevalence of improved housing (with improved water and sanitation, sufficient living area and durable construction) doubling from 11% (95% confidence interval, 10–12%) to 23% (21–25%). However, 53 (50–57) million urban Africans (47% (44–50%) of the urban population analysed) were living in unimproved housing in 2015. We provide high-resolution, standardized estimates of housing conditions across sub-Saharan Africa. Our maps provide a baseline for measuring change and a mechanism to guide interventions during the era of the Sustainable Development Goals