A Framework for analyzing socioeconomic, health and environmental impacts of wastewater use in agriculture in developing countries

Waste water management / Environmental degradation / Waterborne diseases / Water quality / Irrigation practices / Aquaculture / Economic analysis / Social aspects / Health / Environmental aspects / Agriculture / Developing countries / Policy

A Holistic View of Global Croplands and Their Water Use for Ensuring Global Food Security in the 21st Century through Advanced Remote Sensing and Non-remote Sensing Approaches

This paper presents an exhaustive review of global croplands and their water use, for the end of last millennium, mapped using remote sensing and non-remote sensing approaches by world’s leading researchers on the subject. A comparison at country scale of global cropland area estimated by these studies had a high R2-value of 0.89–0.94. The global cropland area estimates amongst different studies are quite close and range between 1.47–1.53 billion hectares. However, significant uncertainties exist in determining irrigated areas which, globally, consume nearly 80% of all human water use. The estimates show that the total water use by global croplands varies between 6,685 to 7,500 km3 yr−1 and of this around 4,586 km3 yr−1 is by rainfed croplands (green water use) and the rest by irrigated croplands (blue water use). Irrigated areas use about 2,099 km3 yr−1 (1,180 km3 yr−1 of blue water and the rest from rain that falls over irrigated croplands). However, 1.6 to 2.5 times the blue water required by irrigated croplands is actually withdrawn from reservoirs or pumping of ground water, suggesting an irrigation efficiency of only between 40–62 percent. The weaknesses, trends, and future directions to precisely estimate the global croplands are examined. Finally, the paper links global croplands and their water use to a paradigm for ensuring future food security

Regional disparities in the beneficial effects of rising CO2 concentrations on crop water productivity

Rising atmospheric CO2 concentrations ([CO2]) are expected to enhance photosynthesis and reduce crop water use1. However, there is high uncertainty about the global implications of these effects for future crop production and agricultural water requirements under climate change. Here we combine results from networks of field experiments1, 2 and global crop models3 to present a spatially explicit global perspective on crop water productivity (CWP, the ratio of crop yield to evapotranspiration) for wheat, maize, rice and soybean under elevated [CO2] and associated climate change projected for a high-end greenhouse gas emissions scenario. We find CO2 effects increase global CWP by 10[0;47]%–27[7;37]% (median[interquartile range] across the model ensemble) by the 2080s depending on crop types, with particularly large increases in arid regions (by up to 48[25;56]% for rainfed wheat). If realized in the fields, the effects of elevated [CO2] could considerably mitigate global yield losses whilst reducing agricultural consumptive water use (4–17%). We identify regional disparities driven by differences in growing conditions across agro-ecosystems that could have implications for increasing food production without compromising water security. Finally, our results demonstrate the need to expand field experiments and encourage greater consistency in modelling the effects of rising [CO2] across crop and hydrological modelling communities

A synthesis of past, current and future research for protection and management of papyrus (Cyperus papyrus L.) wetlands in Africa

Papyrus wetlands (dominated by the giant sedge Cyperus papyrus L.) occur throughout eastern, central and southern Africa and are important for biodiversity, for water quality and quantity regulation and for the livelihoods of millions of people. To draw attention to the importance of papyrus wetlands, a special session entitled ‘‘The ecology of livelihoods in papyrus wetlands’’ was organized at the 9th INTECOL Wetlands Conference in Orlando, Florida in June 2012. Papers from the session, combined with additional contributions, were collected in a special issue of Wetlands Ecology and Management. The current paper reviews ecological and hydrological characteristics of papyrus wetlands, summarizes their ecosystem services and sustainable use, provides an overview of papyrus research to date, and looks at policy development for papyrus wetlands. Based on this review, the paper provides a synthesis of research and policy priorities for papyrus wetlands and introduces the contributions in the special issue. Main conclusions are that (1) there is a need for better estimates of the area covered by papyrus wetlands. Limited evidence suggests that the loss of papyrus wetlands is rapid in some areas; (2) there is a need for a better understanding and modelling of the regulating services of papyrus wetlands to support trade-off analysis and improve economic valuation; (3) research on papyrus wetlands should include assessment of all ecosystem services (provisioning, regulating, habitat, cultural) so that trade-offs can be determined as the basis for sustainable management strategies (‘wise use’); (4) more research on the governance, institutional and socio-economic aspects of papyrus wetlands is needed to assist African governments in dealing with the challenges of conserving wetlands in the face of growing food security needs and climate change. The papers in the special issue address a number of these issues

Financing resource recovery and reuse in developing and emerging economies: enabling environment, financing sources and cost recovery

Resource recovery and reuse (RRR) of domestic and agro-industrial waste has the potential to contribute to a number of financial, socioeconomic and environmental benefits. However, despite these benefits and an increasing political will, there remain significant barriers to build the required up-front capital which is discouraging private sector engagement. A systematic analysis and understanding of the enabling environment, public and private funding sources, risk-sharing mechanisms and pathways for cost recovery can help to identify opportunities to improve the viability of RRR solutions. This report looks at regulations and policies that remove disincentives for RRR, public and private funding sources for capital and operational costs, risk mitigation options through blending and structuring finance, and options for operational cost recovery

Impact of HIV/AIDS on food and nutrition security: the case of Dire Dawa City administration, Ethiopia

In Hanjra, Munir A. (Ed.). Global food security: emerging issues and economic implications. New York, NY, USA: Nova Science PublishersGlobal Agriculture DevelopmentsThis study examined the links between food security and HIV/AIDS in urban Ethiopia taking Dire Dawa city administration as a case example. The household level primary data were collected from selected kebeles - the lowest administrative unit in Ethiopia, - using a two stage sampling technique. In the first stage, four kebeles were selected due to their large number of known cases of people living with HIV (PLHIV). In the second stage, 200 households were randomly selected, taking 100 households each from HIV affected and non-affected category. Both quantitative and qualitative data were collected using well structured and pre-tested questionnaires, and key informant interviews and focus group discussions, which were held with the community members. Using weekly recall period, the data on food variety and quantity consumed were obtained from the principal person preparing food in the household, and then food consumption score was computed using the model developed by the World Food Program (poor consumption, borderline consumption, and better consumption with a score of 35, respectively). Based on the results of the descriptive statistics, it was found out that food consumption score of HIV/AIDS affected and non-affected households were of 35.73 and 37.65, respectively suggesting that the latter are better off. About 70% of HIV affected households have food consumption score of less than 31.5 against 57% of the non-affected ones. Regression results of the ordered logit model also confirm this finding; holding all other variables constant, the marginal effect of being affected by HIV significantly increases the probability of the household being at poor and border line consumption category by 3.13% and 12.49%, respectively. On the other hand, being HIV affected decreases (by 15.62%) the probability of being in the better food consumption category. Thus HIV affected households were less likely to be food secure. Regression results further revealed that, ceteris paribus, participating in social networks significantly increased (by 20.01%) the probability of a household being in a better food consumption category. This suggests that socially isolated households may experience worse food insecurity situation because of lack of supportive safety nets that could shield them against shocks. Results further show that the coping strategies of HIV affected households include, among others, relying more on poor quality food, reducing the daily quantity of food intake and restricting the food consumption of adults in the family so that children can get a chance to eat. For households having fewer social networks and less diversified income sources, these stand out to be 'better' and affordable coping mechanisms. However, these coping strategies may hasten the death of HIV affected adult family members by weakening their health as they need more energy and proteins than non-affected ones. This was very well established during key informant interviews and focus group discussions. Therefore, future interventions should develop the capacity of both formal (legally established) and informal community based organizations to help avoid any forms of stigma or discrimination based on age, gender or sickness. Besides, it is vital to strengthen the human capital of HIV affected households and build resilient communities through better targeting and business skills development programs