Changing land use and land cover

The Ecological, Socioeconomic and Spatial Mechanisms Behind Malaria Transmission in Rural Madagascar in the Face of Land Use Change

Authors: Nicholas Arisco1, Christopher D. Golden1,2, Benjamin L. Rice3, Luciano M. Tantely, Romain Girod4, Hervet J. Randriamady5,6
Author Affiliations: 1Department of Environmental Health, Harvard T.H. Chan School of Public Health; 2Planetary Health Alliance, Australia; 3Department of Organismic and Evolutionary Biology, Harvard University; 4Institut Pasteur de Madagascar; 5Madagascar Health and Environmental Research (MAHERY); 6MAHERY Health Program, Catholic Relief Services, Madagascar

Background Large-scale deforestation and subsequent land use change is widespread in Madagascar. This disruption of natural systems causes shifting patterns of species distribution, diversity, and abundance in Madagascar’s ecosystems. Humans inhabiting rural Madagascar intimately and frequently interact with their natural environments, and this interface predicates their health status. Limited data exist to explore the mechanistic pathways behind Madagascar’s chronic and acute disease burden. Here we will specifically explore the ecological, socioeconomic, and spatial mechanisms underpinning malaria prevalence across five ecoregions in Madagascar.

Methods We studied 31 communities across five ecoregions in Madagascar. We collected data on the ecology and spatial distribution of mosquito species composition and malaria infections through larval collection and geospatial mapping of larval habitats. These data were spatially linked to socioeconomic and health data. We will build Bayesian regression models followed by piecewise structural equation models to determine hierarchal paths for malaria risk linking land use change to malaria infection risk in a semi-causal framework.

Findings Our empirical collection of mosquito larvae confirmed the presence of Anopheles larvae in 16 of the 31 communities. Species present were A. squamosus, A. coustani, A. mascarensis, and A. gambiae s.l. Anopheles larvae were primarily found in rice fields, though there were Anopheles positive human-made pools of water in arid regions. Preliminary data indicate clustering of malaria cases within households and among household groupings. Clustering seems random at the household level with respect to nearby Anopheles habitats. Further statistical analyses will explore the link between variables such as occupation, proximity to rice fields, local larval habitat abundance, and regional climate variables and individual/household malaria prevalence.

Interpretation Anopheles larvae were commonly present in human-made ponds for livestock and rice paddies, indicating that livestock raising and agriculture could present risk of malaria transmission. Preliminary findings also show possible local transmission in arid regions not expected to exhibit transmission, although these sites could be easily controlled with spraying and active prevention. Malaria cases exist in sites with no positive larval breeding habitats, indicating migration of cases into these communities or preserved infections from past periods when local transmission was possible. Rapid land-use change may open opportunities for Anopheles sp. to colonize in new regions. Introduction of vectors coupled with low human population immunity will lead to more severe cases in these previously unaffected regions. Understanding mechanistic pathways for malaria transmission in these communities will inform control programs on the most efficient, targeted intervention points.

Relationships between forests, deforestation and nutritional outcomes: an observational study in nine African countries

Authors: Thomas Pienkowski1, B. Dickens2, H. Sun3, A.S Waldron, W. Symes3, L.R. Carrasco3
Author Affiliations: 1Department of Zoology, University of Oxford; 2Saw Swee Hock School of Public Health, University of Singapore; 3Department of Biological Sciences, University of Singapore

Background: Ecosystems have complex relationships with public health, and environmental degradation can disrupt important health related ecosystem services. Agricultural expansion is a leading driver of deforestation, yet malnutrition remains a significant cause of morbidity. It is therefore important to understand the links between forest cover, deforestation and indicators of malnutrition when managing landscapes for sustainable development. Recent research has illustrated the importance of forests in supporting dietary diversity. However, there remains little evidence of the effects of forest on broad nutritional outcomes such as underweightness.

Methods: We explored relationships between nutritional outcomes in children under five years of age and forest cover and loss gradients (in 10km buffers around communities) in 61,032 African households between 2003 and 2014. USAID Demographic Health Survey data was combined with spatially explicit land cover, climatic, infrastructural, and demographic data in a series of generalized linear mixed-effects models. These models explored the role of forests and deforestation on children’s nutritional outcomes, the mediating effect of socio-economic and infrastructural context, and how these relationships changed over time.

Findings: In urban areas, children in communities surrounded by one standard deviation (SD) higher forest cover than the mean experienced 10.8% (95% CI 3.0%–18.0%, p = 0.0073) lower incidence of underweightness and 11.7% (95% CI 1.9–20.6%, p = 0.0212) less wasting. However, in rural areas the relationship was reversed, with children suffering 6.0% (95% CI 1.6%–10.6%, p = 0.0074) higher incidence of underweightness in areas of higher forest cover. Additionally, underweightness was 6.7% (95% CI 1.4%–12.3%, p= 0.0124) higher in urban areas and 2.6% (95% CI 0.04%–5.2%, p = 0.0460) higher in rural areas with one SD greater deforestation, although this relationship appeared to diminish over time.

Interpretation: Forest loss appears to be associated with worse nutrition in the short term, although unmeasured frontier migration may play a role. Our results also suggest that forest cover is associated with worse nutritional outcomes in rural areas but better outcomes in urban areas of Africa. Our study does not explicitly measure the role of forests in improving dietary diversity. Therefore, the extent to which the benefits of forests in reducing the ‘hidden hunger’ of micro-nutrient deficiency are offset by potential costs is not clear. Nevertheless, these health costs should be recognised and accounted for in efforts to meet sustainable development objectives.

Harnessing agricultural biodiversity and managing landscapes for improved nutrition and well-being in Sri Lanka

Authors:Azra Sartaj1, W.L.G Samarasinghe1, D. Hunter2,3
Author Affiliations: 1Plant Genetic Resources Center and Biodiversity for Food and Nutrition Project; 2Bioversity International, Italy & Health Food Systems node; 3Charles Perkins Centre, University of Sydney

Background: Profound change including poor land use practices, habitat mismanagement, land degradation, misuse of agro-chemicals, deforestation and urbanization has meant once healthy ecosystems are struggling to sustain production systems and other essential services in Sri Lanka. It is estimated around 750,000 people struggle to adapt to adverse changing climate especially severe drought and flash floods. This lack of adaptability in turn drastically affects ecosystem services essential to sustain human health and well-being including the provision of food and healthy diets, biodiversity and habitats, soil and water quality.

Methods: Baseline assessments involving field visits, group discussions and questionnaire surveys were undertaken in three unique agro-ecosystems: the village tank cascade system; ‘Kandyan’ home gardens; and, ‘Owita’ peri-urban system to determine agrobiodiversity status, food security status, dietary diversity, socio-economic status and associated traditional knowledge. Subsequently food composition analysis, ethno-botany studies and value chain analysis of local agro-biodiversity were conducted.

Findings: Baseline assessments revealed local food production systems are under threat including reduction in the diversity and consumption of available food, loss of traditional knowledge, culture and skills. Food insecurity percentages of 59.9%, 60.2% and 21% respectively were recorded while the incidence of diet related nutrition and health problems, including stunting, wasting, under-weight and NCDs, continue to rise. Surveys depicted marketing value chains needs to be strengthened for new biodiversity products to enhance agribusinesses around local biodiversity with identified nutrition indicators.

Interpretations: Underutilized and locally-adapted agrobiodiversity has been identified and prioritized, based on criteria including food composition data, to address common nutritional deficiencies especially iron, vitamin A and zinc, while at the same time promoting biodiversity conservation. Foxtail millet (Setaria italic), wood apple (Limonia acidissima) and leafy vegetables including Centella asiatica, Alternanthera sessilis & Sesbania grandiflora have been identified as excellent sources of micro-nutrients. These target crops, and others, are being introduced and promoted into home gardens and surrounding farming landscapes to enhance not only household food security but also the management and diversity of agroecosystems via land restoration and the revitalization of indigenous crops with high nutritional value. Furthermore, the target crops also contribute to livelihood improvement: promotion of organic cultivation methods with certification systems such as participatory guarantee schemes is promoted amongst smallholder growers to increase supply with an emphasis on premium pricing. They also grow well without overuse or reliance on agrochemicals, an added benefit for human health and agroecosystems. Findings are being used for formulation of improved policies and marketing guidelines related to ecosystems, agrobiodiversity, nutrition and health using a holistic approach to promote cross-sectorial policy and value chain platforms.

Integrating ecological and equity dynamics into the development of an Environment, Community, Health Observatory Network: Lessons for complexity-oriented research in the Anthropocene

Authors: Maya Gislason1, Margot W. Parkes1
Author Affiliations: 1School of Health Sciences, University of Northern British Columbia

Background:
Natural resource extraction is one way that humans profoundly impact the geologic record as well as the health and resilience of communities already contending with complex social and ecological changes. The impacts of intensive resource development have created an “integration imperative” as their environmental, community and health impacts need to be understood in terms of their cumulative influences on the health of people, places and animals across their life course. The urgency of the “integration imperative” is especially felt in rural, remote, northern and Indigenous communities where most intensive resource extraction occurs, and the need for more sustainable approaches to the management of the cumulative impacts of multiple resource development projects is evident.

Methods:
In this presentation, we will examine ways combined equity and ecosystem dynamics have been addressed during the foundational phase of a five-year international project, titled: “Environment, Community, Health Observatory (ECHO) Network: Strengthening intersectoral capacity to understand and respond to health impacts of resource development”. The ECHO project is based in Canada and is developing partnerships in Australia and New Zealand. By bringing together a diverse range of disciplines, sectors and stakeholder groups this project is refining methods for building integrative understanding and responses to the cumulative determinants of health, in relation to social and ecosystem change. The project has responded to the combined equity and ecosystem dynamics of cumulative impacts by prioritising equity-informed research across all four regional case studies in Canada, drawing on critical social theory and social inequities and health frameworks that incorporate both intersectoral and intersectional considerations.

Findings:
The foundational phase of research has highlighted the need to attend to pathways of influence that extend beyond the typical purview of health research, where ‘upstream’ includes places, waterways, landscapes and drivers of change, that are well outside the traditional ‘spheres of influence’ of the health sector, and which have combined implications for health equity and the ecological determinants of health. Our initial phase of research has also highlighted challenges and opportunities arising when equity considerations are incorporated into learning about a new generation of tools and processes that local, regional and international partners are using to “take notice for action”.

Interpretation:
Discussion will focus on the importance of both equity and ecological considerations when designing research that responds to the “integration imperative”, furthers evidence of cumulative determinants of health impacts and incorporates attention to the complex challenges facing health and sustainability agendas in the Anthropocene.

Role of Participatory Forest Management (PRM) and Integrating Population Issues in Forest Conservation and Sustainable Use: The Case of Gimbo Woreda, South West Ethiopia 

Author: Endashaw Mogessie Tiruneh1
Author Affiliation: 1PHE Ethiopia Consortium 

Introduction and Background
This study was conducted on Bonga forest which represents one of the remaining afromontane forest tracts of Ethiopia. The study area was located at the head water of the Omo-Gibe Basin harbors the highest biodiversity. The main objective of the research was to assess on the role of participatory forest management and integration of population and health issues in forest conservation and sustainable use.

Methods
The study has employed 1) forest inventory for vegetative data collection on forest structure, 2) land use and land cover change analysis using satellite image to see land use and land cover in forests under participatory forest management practice and non-participatory forests management practice, and 3) questionnaire survey for understanding population issues and management practices. The vegetative data was collected from 70 plots. Assessment was done on the social and demographic aspects of the forest management practices through the questionnaire survey involving 120 households.

Results
The total plant density was found to be 3976 individuals/ha for PFM forests and 2834 individuals/ha for non-PFM forests where Coffea Arabica L. has the highest density to both forest blocks. The total forest basal area was calculated and found to be 110.189 and 104.725 m2/ha for the PFM and non-PFM forests. The questionnaire survey has demonstrated that there was better forest management practices in the PFM forests. The trends of deforestation through the periods 1985 to 2015 were analyzed using the satellite images. The forest cover has deceased at a rate of 4.9%, 4.5% and 15% for the period of 1985 to 1995, 1995 to 2005 and 2005 to 2015 respectively. On the other hand, the forest cover has decreased at a rate of 5%, 7% and 20% for the period of 1985 to 1995, 1995 to 2005 and 2005 to 2015 respectively. It was found that there was limitation of integrating population issues including reproductive health activities. On the other hand the results of the study has showed that, there is strong practices of allocating land to new youths which is strong threat to the previous biodiversity resources of the area.

Conclusion
The study has revealed the positive role of PFM in forest conservation and sustainable use. PFM has played strong role in creating ownership and stewardship towards the forest resources. Moreover, the Participatory Forest Management Cooperatives are better involved in integrating population and heath issues in the forest management plan implementation. The comparison of the assessment results on the different parameter has showed that a relatively better forest conservation and sustainable use put in place in the PFM forests than the non-PFM forests. In general the study has showed community participation and engagement in management forests has better contribution for conserving the resources and enhancing the benefits.

Impact of global change on future Ebola emergence and epidemic potential in Africa

Author: Kate Jones1, David Redding1
Author Affiliations: 1University College London

Animal-borne or zoonotic human diseases (e.g., SARS, Rabies) represent major health and economic burdens throughout the world, disproportionately impacting poor communities. In 2013-2016, an outbreak of the Ebola virus disease (EVD), a zoonotic disease spread from animal reservoirs caused by the Zaire Ebola virus (EBOV), infected approximately 30,000 people, causing considerable negative social and economic impacts in an unexpected geographical location (Sierra Leone, Guinea, and Liberia). It is not known whether the spatial distribution of this outbreak and unprecedented severity was precipitated by environmental changes and, if so, which areas might be at risk in the future. To better address the major health and economic impacts of zoonotic diseases we develop a system-dynamics approach to capture the impact of future climate, land use and human population change on Ebola (EVD). We create future risk maps for affected areas and predict between a 1.75 and 3.2-fold increase in EVD outbreaks per year by 2070. While the best case future scenarios we test saw a reduction in the likelihood of epidemics, other future scenarios with high human population growth and low rates of socioeconomic development saw a fourfold increase in the risk of epidemics occurring and almost 50% increase in the risk of catastrophic epidemics. As well as helping to target where health infrastructure might be further developed or vaccines best deployed, our modelling framework can be used to target global interventions and forecast risk for many other zoonotic diseases.

Overview of the Suggestion for the Establishment of the Grazing Reserve Bill and the Farmer – Herdsmen Rifts in Nigeria

Author: Michael Oke1, Muyiwa Oke2
Author Affiliations: 1Farm Management and Extension; 2Michael Adedotun Oke Foundation

The Law governing the establishment of grazing reserves in Nigeria started in 1965 later in 1978, the land Acts was extended to cover it. In 1988 National policy also earmarked 10 percent of the total National Territory for grazing areas that is 9.8 million hectares of land were earmarked in 1988 for grazing reserves. That figure was later increased to 20 Million hectares. This paper supported the establishment of the Grazing reserve bill, which is the objectives to review different views, after considering the different write up in the daily newspaper of 2015 and 2016 and pictures. There are less than three million hectare gazette grazing areas which cover about three million. We have about 415 grazing areas and grazing reserves. Out of the 415, 141 were gazette. And those 141 reserves gazette cover only about three million hectares of land, it has been damaged by ecology, encroachment. The clashes came as result of the absence of developed grazing reserves and the protection of those reserves, suffered a lot of neglect because the pastoralist livelihood has been frequently undermined by unfriendly policies and laws. The polices of the past administration have given more attention to agronomy and not livestock sector that is what has caused this problems, three million hectares have been destroyed. The forestry units must work effectively to protect the reserves.


Oil extraction in the Peruvian Amazon basin and exposure to metals in indigenous populations

Author: Cristina O’Callaghan-Gordo1, Juan A. Flores2Pilar Lizárraga2Tami Okamoto3, Diana M. Papoulias4, Federica Barclay5Martí Orta-Martínez6, Manolis Kogevinas1, John Astete2
Author Affiliations: 1ISGlobal; 2National Institute of Health-Centro Nacional de Salud ocupacional y Protección del Ambiente para la Salud; 3Pontificia Unviersidad Católica del Perú; 4E-Tech International; 5Centro de políticas Públicas y Derechos Humanos; 6International Institute of Social Studies, Erasmus University Rotterdam

Background:
Poor environmental practices by the oil industry and recurrent oil spills have contaminated the Corrientes, Pastaza, Tigre and Marañon river basins (Peru). Recent data have shown that wildlife species that play an important role in the diet of rural Amazonian human populations consume oil-contaminated soils and water. Indigenous population living in this area are exposed to metals and other contaminants related to oil extraction activities by diverse routes of exposure. We are currently measuring levels of exposure to metals and hydrocarbons in the population of these four basins and evaluating potential sources and routes of exposure. Data presented here correspond to a study conducted in the Marañón basin where we measured levels of exposure to metals in two Kukama communities. A wider study of the whole region is ongoing.

Methods:
In January 2016 we visited two Kukama communities to assess blood and urine levels of heavy metals. Participation was offered to all inhabitants that had been living in these communities during at least the previous six months. Demographic data and information on involvement in oil clean-up activities were collected through questionnaires. Venous blood and urine were collected. Concentrations of lead in blood, and arsenic, cadmium, and mercury in urine were determined using atomic absorption spectrophotometry (AAS) (AAS in graphite chamber for lead and cadmium, flow injection –hydride generation AAS for arsenic, and cold vapour AAS for mercury).

Findings:
Nine percent of the population (132/1400) participated in the survey. 19% of children ≤ 10 years had blood lead levels above 5 µg/dL. No participant exceeded arsenic benchmarks recommended by the Peruvian Ministry of Health (MINSA, i.e. 20 µg arsenic/g creatinine). 17% and 50% of the study population exceeded levels recommended by the MINSA for cadmium (2 µg cadmium/g creatinine) and mercury (5 µg mercury/g creatinine), respectively. These percentages were higher among children ≤ 10 years: 18% and 64% of them had cadmium and mercury levels higher than those recommended, respectively. Participants involved in clean-up activities had higher blood lead than those not involved in clean-up.

Interpretation:
Individuals in these two communities have levels of mercury, cadmium and lead that can be detrimental to health. Recurrent oil spills, may be a source of exposure to these metals, although we cannot exclude the existence of other sources of exposure, especially for mercury. Results of the larger ongoing project will help in the identification of sources and routes of exposure.

Ecosystem Services Provided by the Village Tank Cascade System (VTCS) in Sri Lanka: A Case Study of Bellankadawala VTCS

Author: Gamini Pushpakumara1PB Dharmasena2Harsha Kadupitiya3, Jeevika Weerahewa1, Sujith Rathnayake4, Danny Hunter5,6
Author Affiliations: 1University of Perdeniya; 2FAO, Sri Lanka; 3Natural Resources Management Centre, Department of Agriculture, Sri Lanka; 4Ministry of Mahaweli Development and Environment, Sri Lanka; 5Bioversity International, Italy and Healthy Food Systems node; 6Charles Perkins Centre, University of Sydney

The Village Tank Cascade System (VTCS) is an ancient and unique agricultural system mainly found in the dry and intermediate zones of Sri Lanka, and covers around 20% of land area of the country. The basic structure of a VTCS is a cluster of hydrologically, ecologically and socially inter-connected tanks built to collect, store, purify and utilize rainwater for humans and animal consumption and agricultural purposes. An upstream forest catchment, tree strip and a meadow, a soil ridge, seepage interceptor, a paddy field with a common drainage and a hamlet buffer have been added to the tank to facilitate the provision of good quality water for irrigation, humans and animals. The ecosystem services provided by these segments in traditional VTCSs were found to be diverse and large. However, over time, some of the above land use segments have been converted to agricultural lands and certain tanks, which were meant for other purposes have also been converted to irrigation tanks. Further, overuse of agrochemicals, silting, pollution of tank water, wildlife-human conflicts, and poorer nutrition of human have also impacted on ecosystem services and human health in VTCSs. This study recorded the nature and degree of provision of ecosystem services in Bellankadawala VTCS complex over time. Field visits and a questionnaire survey conducted among the villagers were used to identify the ecosystem services provided by each segment of the VTCS in the past and the present.

Over time, the upstream forest catchment, meadow, the soil ridge, and the seepage interceptor have been converted to agricultural lands and the common drainage is not functioning in its full capacity or encroached. The hamlet buffer has been used for the construction shelters or agricultural purposes whereas the tree strip has been degraded. With the transformation of the social structure from ancient feudal system to present economic based system, emphasis has been given largely to provisioning services particularly food and with lesser emphasis on regulating and supporting services, and a significant drop in the diversity of provisioning services could be observed (tank as a drinking water, collection of medicinal plants, rattan and reed). The unique cultural services provided by the ancient VTCS are no longer in existence. The results of this study highlight the need for system approach in decision making, scientific restoration of tanks and connected land use segments to widen and deepen the ecosystem services provided by VTCS, including for human health and wellbeing.

Global effects of land use on zoonotic host communities

Author: Rory Gibb1David W. Redding1Kai Chin1, Tim Blackburn1, Tim Newbold1, Kate E. Jones1
Author Affiliations: 1Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London

Background: Environmental trade-offs associated with land use, for example between food security and biodiversity conservation, represent critical dimensions of planetary health. Land use-driven biodiversity losses may predictably affect disease risk if reservoir host species are consistently more likely to persist under human disturbance (i.e. if ecological communities in modified habitats generally have a higher zoonotic potential). Such a phenomenon has been observed in specific disease systems, but with high rates of global land use change projected for this century, assessing its global and taxonomic generality would shed light on an important hypothesised driver of environmental synergies or trade-offs between conservation and public health.

Methods: We combine data on hosts of human-shared parasites and pathogens (‘hosts’) with a global database of local ecological communities and associated land use data (originally collated from published studies). We analyse the effects of land use on host diversity metrics across over 9000 sites globally, controlling for disease-related research effort and differences in survey methods.

Findings: Ecological communities in anthropogenic land uses (managed ecosystems and urban) contain a consistently higher richness and abundance of host species than communities in nearby primary land sites. However, among mammal hosts of zoonotic pathogens, we find considerable taxonomic variation in host responses to land use, with rodent and bat host abundances generally increasing and primate and carnivore hosts declining in modified landscapes.

Interpretation: Our results suggest that future global land use change has potential to drive increasing contact between people and ecological communities with increased shared pathogen potential (i.e. more potential hosts and possible opportunities for transmission). However, the variability among mammals, for example with rodent hosts most abundant in modified habitats and primate hosts most abundant in intact communities, highlights that these changes are unlikely to affect all zoonotic diseases consistently. This result supports arguments that, rather than expecting a consistent biodiversity-disease relationship, in practice policies aiming to both conserve biodiversity and reduce human disease (for example through establishment of protected areas) must be disease- and context-specific.

Relationships between forests, deforestation and nutritional outcomes: an observational study in nine African countries

Author: Thomas Pienkowski1B. Dickens2H. Sun3A.S. Waldron3W. Symes3L.R. Carrasco3
Author Affiliations: 1Department of Zoology, University of Oxford; 2Saw Swee Hock School of Public Health, University of Singapore; 3Department of Biological Sciences, University of Singapore

Background: Ecosystems have complex relationships with public health, and environmental degradation can disrupt important health related ecosystem services. Agricultural expansion is a leading driver of deforestation, yet malnutrition remains a significant cause of morbidity. It is therefore important to understand the links between forest cover, deforestation and indicators of malnutrition when managing landscapes for sustainable development. Recent research has illustrated the importance of forests in supporting dietary diversity. However, there remains little evidence of the effects of forest on broad nutritional outcomes such as underweightness.

Methods: We explored relationships between nutritional outcomes in children under five years of age and forest cover and loss gradients (in 10km buffers around communities) in 61,032 African households between 2003 and 2014. USAID Demographic Health Survey data was combined with spatially explicit land cover, climatic, infrastructural, and demographic data in a series of generalized linear mixed-effects models. These models explored the role of forests and deforestation on children’s nutritional outcomes, the mediating effect of socio-economic and infrastructural context, and how these relationships changed over time.

Findings: In urban areas, children in communities surrounded by one standard deviation (SD) higher forest cover than the mean experienced 10.8% (95% CI 3.0%–18.0%, p = 0.0073) lower incidence of underweightness and 11.7% (95% CI 1.9–20.6%, p = 0.0212) less wasting. However, in rural areas the relationship was reversed, with children suffering 6.0% (95% CI 1.6%–10.6%, p = 0.0074) higher incidence of underweightness in areas of higher forest cover. Additionally, underweightness was 6.7% (95% CI 1.4%–12.3%, p= 0.0124) higher in urban areas and 2.6% (95% CI 0.04%–5.2%, p = 0.0460) higher in rural areas with one SD greater deforestation, although this relationship appeared to diminish over time.

Interpretation: Forest loss appears to be associated with worse nutrition in the short term, although unmeasured frontier migration may play a role. Our results also suggest that forest cover is associated with worse nutritional outcomes in rural areas but better outcomes in urban areas of Africa. Our study does not explicitly measure the role of forests in improving dietary diversity. Therefore, the extent to which the benefits of forests in reducing the ‘hidden hunger’ of micro-nutrient deficiency are offset by potential costs is not clear. Nevertheless, these health costs should be recognised and accounted for in efforts to meet sustainable development objectives.

Forests improve vulnerable children’s diet in rural developing countries

Author: Ranaivo Rasolofoson1Merlin Hanauer2Ari Pappinen3Brendan Fisher1Taylor Rickets1
Author Affiliations: 1Gund Institute for Environment, University of Vermont2Sonoma State Universit; 3University of Eastern Finland 

Background:
Micronutrient malnutrition affects about a third of the world’s population. Children in developing countries are particularly vulnerable. Consequences include impaired cognitive and physical development, and increased childhood morbidity and mortality. Recent studies suggest that forests help alleviate micronutrient malnutrition by increasing diet diversity. However, evidence about the impacts of forests on diet diversity is thin and mostly based on case studies of limited relevance to global policies. Existing evidence is also weak because of poor study design. Furthermore, how impacts of forests on diet diversity vary between and within communities has not received due attention; though such information could point to actions needed to enhance desired impacts.

Methods:
We estimate the impacts of forests on diet diversity of children under five of over 43,000 rural households across 27 developing countries. We strengthen the evidence by using empirical designs that are attentive to assumptions necessary for causal interpretations and adequately account for confounding factors that could mask or mimic the impact. We also investigate how impacts vary with level of development and access to capital, such as markets, roads and education.

Findings:
We find that high exposure to forests causes children to have at least 25% greater dietary diversity compared to lack of exposure. A closer look at a subset of sub-Saharan African countries indicates that impacts are generally higher for less developed communities, but highest with certain level of access to markets and roads, and education.

Interpretation:
Our results are comparable to the impacts of some nutrition-sensitive agricultural programs. Therefore, our study establishes the causal relationship between forests and diet and thus strengthens the evidence for integrating forest conservation and management into portfolios of nutrition interventions. Our results also suggest that complementary measures endowing households some access to capital increase the nutrition-sensitivity of forest related interventions.

Assessing the effect of irrigated agriculture on the risk of Japanese encephalitis transmission in Asia

Author: Lydia Franklinos1Kate Jones1David Redding1, Ibrahim Abubakar1
Author Affiliations: 1University College London

BACKGROUND: Humanity has traded off many of the Earth’s supportive and regulating processes to feed human population growth and development, often with negative consequences for global human health. The use of irrigated agriculture for global food production has more than doubled since the 1960s and is mainly focused in developing countries in Africa and Asia, with future expansion expected in the same regions. Despite the benefits of enhanced global food production and economic development that have come with irrigated agriculture, it has also been associated with an increased risk of mosquito-borne disease. This is due to the dramatic expansion in vector breeding sites that are provided by irrigation, which may extend disease transmission seasons, alter seasonal transmission dynamics in endemic areas and introduce pathogens into non-endemic areas. However, the effects of expanding irrigated agriculture on the seasonality and geographic distribution of mosquito-borne disease risk remains poorly understood.

METHODS: We used a Bayesian spatial model using Integrated Laplace Approximations (INLA), to investigate environmental drivers of Culex tritaeniorhynchus occurrence; the main vector for Japanese encephalitis (JE). The model was used to create a novel dataset of spatio-temporal predictions for Culex tritaeniorhynchus retrospectively at time points over the last 20 years, and then summarised to give 12 monthly spatial predictions at a continental scale.

FINDINGS: The new data resource can be used to determine how environmental drivers vary spatially and temporally and how they may affect the transmission risk of JE, the most significant cause of viral encephalitis in Asia. This enables the identification of areas that are vulnerable to JE transmission risk under current and future levels of global change.

INTERPRETATION: This study contributes towards efforts determining the importance of underlying environmental drivers for JE transmission risk, and can be used to predict the impact of irrigation schemes and identify key areas where interventions should be prioritised within a changing planet.

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