This chapter explores how changes in land use, climate, and the function of ecosystems may act synergistically to alter exposure to infectious disease and natural disasters and curtail access to food, clean air, and clean water – basic components of the public’s health. It focuses on the greatest emerging threats from climate and large-scale, anthropogenic changes to landscapes and natural systems for ecosystem services: food production and clean water provision. These 2 are difficult to study using traditional approaches as they are multi-factoral and complex and often occur over very large scales. Ample evidence exists regarding alterations to disease transmission; most but not all show increases. Mechanisms by which changes occur include: changes in the density or presence of disease-related organisms; changes in exposure pathways; and changes in community species composition. Food and water scarcity combined with greater vulnerability to natural disasters may lead to much higher morbidity and mortality e.g. from malnutrition and chronic hunger, particularly in SSA and parts of SE Asia experiencing ecological constraints to local food production due to soil degradation and water scarcity. Water is also needed for drinking, sanitation, hygiene, and food preparation - inadequate access causes millions of deaths. Climate change is expected to worsen water scarcity. Depletion of ecosystem services might impact health only when resources are very constrained and a threshold is reached. Vulnerability to natural disasters (fires, floods, storms, tidal waves, landslides) influences how changing environmental conditions may impact human health. Vulnerability differs by socioeconomic status and by gender (especially women) and age. This summary is not an official abstract. Users should refer to the original published version of the material for the full abstract
Ecosystem-service production is strongly influenced by the landscape configuration of natural and human systems. Ecosystem services are not only produced and consumed locally but can be transferred within and among ecosystems. The time and distance between the producer and the consumer of ecosystem services can be considered lags in ecosystem-service provisioning. Incorporation of heterogeneity and lag effects into conservation incentives helps identify appropriate governance systems and incentive mechanisms for effective ecosystem-service management. These spatiotemporal dimensions are particularly apparent in river–riparian systems, which provide a suite of important ecosystem services and promote biodiversity conservation at multiple scales, including habitat protection and functional connectivity. Management of ecosystem services with spatiotemporal lags requires an interdisciplinary consideration of both the biophysical landscape features that produce services and the human actors that control and benefit from the creation of those services.
By the year 2050, agriculture will have to provide the food and nutrition requirements of some 9 billion peo- ple. Moreover, to maintain that level of productivity indef- initely it must do so using environmentally sustainable production systems. This task will be profoundly compli- cated by the effects of climate change, increasing compe- tition for water resources and loss of productive lands. Agricultural production methods will also need to recog- nize and accommodate ongoing rural to urban migration and address a host of economic, ecological and social concerns about the ‘high inputs/high outputs’ model of present-day industrial agriculture. At the same time, there is a need to confront the unacceptable levels of continuing food and nutrition insecurity, greatest in the emerging economy countries of Africa and Asia where poverty, rapid population growth and climate change present additional challenges and where agriculture is practiced primarily by small-scale farmers. Within this context, we here review science-based evidence arguing that diversification with greater use of highly valuable but presently under- valorised crops and species should be an essential element of any model for sustainable smallholder agriculture. The major points of these development opportunity crops are presented in four sections: agricultural farming systems, health and nutrition, environmental sustainability and pros- perity of the populations. For each section, these crops and their associated indigenous knowledge are reported to bring benefits and services when integrated with food systems. In this paper, we conclude that not only a change in policy is needed to influence behaviours and practices but also strong leadership able to synergize the various initiatives and implement an action plan.
African savannas are home to an abundant and diverse assemblage of wild herbivores, but the very grasses that sustain these wild herds also make savannas attractive to humans and their livestock. We used the Kenya Long-term Exclosure Experiment to investigate the ecological effects of different combinations of native and domestic grazers. The experimental removal of large grazing mammals set into motion a cascade of consequences, beginning with the doubling in abundance of a small grazing mammal, the pouched mouse (Saccostomus mearnsi). The presence of abundant mice attracted venomous snakes such as the olive hissing snake (Psammophis mossambicus); devastated seedlings of the dominant tree (Acacia drepanolobium); and doubled the abundance of fleas, which potentially increased the risk of transmission of flea-borne pathogens. Together, these results show the potential for the loss of large mammals to have cryptic consequences for African savannas, with important and often undesirable repercussions for humans.
Food insecurity and malnutrition in local populations both result from and drive deforestation. This paper examines the relationships between diet of local people and measures of forest cover and use in the East Usambara Mountains, Tanzania. Data on dietary diversity and intake were collected for 270 children and their mothers. Area of tree cover within the vicinity of each household was examined in relation to forest use and diet. Individuals using foods from forest and other non-farm land had higher dietary diversity, consumed more animal source foods and had more nutrient dense diets. They also had more tree cover in a close proximity to the home, suggesting a relationship between tree cover and forest food use. Households reporting trips to the forest had lower area of tree cover within close proximity, suggesting that land close to the home with tree cover such as agroforest and fallow is important for obtaining subsistence products. Although historically there has been little motivation for local people to participate in forest conservation in the East Usambaras, the maintenance of tree cover in the landscape around the home, especially on agricultural and village land, may be important in ensuring continued access to the health benefits potentially available in wild and forest foods.
Health issues of forest women in developing countries merit more serious attention. This paper reviews existing literature on the interface of women, health and forests to highlight conservation opportunities and challenges. Most women in forests are collectors and users of forest species. However, existing conservation efforts, deforestation, poor health services and household responsibilities can intensify health and safety concerns for forest dependent women. Women are likely to bear the strenuous burden of carrying fuelwood (and other forest products) long distances and inhaling smoke while cooking. The burden of unintended childbearing, diseases and cultural issues can compound their health problems. To improve local livelihoods and environments, some organisations have initiated activities that integrate conservation and human health objectives, including family planning. This article provides project examples, where the involvement of women has been identified as a key component in effectively meeting both conservation and development goals.
Protein from forest wildlife is crucial to rural food security and livelihoods across the tropics. The harvest of animals such as tapir, duikers, deer, pigs, peccaries, primates and larger rodents, birds and reptiles provides benefits to local people worth millions of US$ annually and represents around 6 million tonnes of animals extracted yearly. Vulnerability to hunting varies, with some species sustaining populations in heavily hunted secondary habitats, while others require intact forests with minimal harvesting to maintain healthy populations. Some species or groups have been characterized as ecosystem engineers and ecological keystone species. They affect plant distribution and structure ecosystems, through seed dispersal and predation, grazing, browsing, rooting and other mechanisms. Global attention has been drawn to their loss through debates regarding bushmeat, the “empty forest” syndrome and their ecological importance. However, information on the harvest remains fragmentary, along with understanding of ecological, socioeconomic and cultural dimensions. Here we assess the consequences, both for ecosystems and local livelihoods, of the loss of these species in the Amazon and Congo basins.
We identify four principles that can promote the prospects of health outcomes for desert Aboriginal people from livelihoods engaged with land management. The principles were derived inductively using a grounded theory approach, drawing on primary research that used qualitative and participatory methods, and from relevant literature and theoretical frameworks. International and Australian literature offers evidence that supports desert Aboriginal people’s view that their health depends on their relationship with their land. Engagement with land management can lead desert Aboriginal people to feel that their own actions are consistent with their own sense of the right and proper way for them to behave towards land, family and community. This increased ‘sense of control’ impacts positively on health by moderating the impact of sustained stress from health risk factors in the environment and lifestyle. The four principles focus on underlying characteristics of Aboriginal land management that are important to promoting this increased ‘sense of control’: (1) Aboriginal land management governance recognises and respects Aboriginal custom and tradition, and is adaptive; (2) learning is embraced as a life-long process; (3) relationships are recognised as very important; and (4) partnerships give priority to doing things that all parties agree are important. These principles are presented as hypotheses that warrant further development and testing. While they do not account specifically for the impact of lifestyle and environmental factors on health, we expect that the increased sense of control that desert Aboriginal people are likely to develop when involved in Aboriginal land management that applies these principles will moderate the impact of such factors on their health. The principles offer a starting point for further development of criteria and standards for good practice in Aboriginal land management, potentially including an environmental certification scheme that integrates social and environmental outcomes.
HIV/AIDS can present a significant economic, medical, and psychological shock to households in sub-Saharan Africa, and can considerably alter household livelihood behavior. While there is speculation that household impoverishment related to HIV-affliction and the onset of AIDS can drive households into greater dependence on their local, natural environment for food, medicine, fuel, construction materials, and other products, evidence is limited. This study queried the 2008-2009 Kenyan Demographic Health Survey Database for associations at the national level between household HIV-affliction and three natural resource use variables: primary household fuel type, drinking water source, and presence in the household of an adult self-reporting as a subsistence fisheries or agricultural worker. Manual, step-wise binomial and multinomial logistic regression models (N=4000+ households) were constructed to examine these associations while controlling for geographic and socio-demographic factors. Model results demonstrated that HIV- afflicted households were 40-70% less likely than un-afflicted households to use natural fuels compared to processed fuels, and 30% less likely (weighted model, only) to rely on surface water sources compared to purchased or engineered water
sources. No difference was detected between HIV-afflicted versus un-afflicted households regarding presence of an adult engaged in subsistence fishery or agricultural work. While a cross-sectional analysis limits discussion of causality, possible explanations include household adaptation to labor loss and/or increased exposure to HIV infection of communities with access to infrastructure. The results of this study caution against case study bias in the existing HIV-environment literature, and highlight the need for randomized, longitudinal studies on this topic.
Mangroves are found throughout the tropics, providing critical ecosystem goods and services to coastal communities and supporting rich biodiversity. Despite their value, world-wide, mangroves are being rapidly degraded and deforested. Madagascar contains approximately 2% of the world’s mangroves, >20% of which has been deforested since 1990 from increased extraction for charcoal and timber and conversion to small to large-scale agriculture and aquaculture. Loss is particularly prominent in the northwestern Ambaro and Ambanja bays. Here, we focus on Ambaro and Ambanja bays, presenting dynamics calculated using United States Geological Survey (USGS) national-level mangrove maps and the first localized satellite imagery derived map of dominant land-cover types. The analysis of USGS data indicated a loss of 7659 ha (23.7%) and a gain of 995 ha (3.1%) from 1990–2010. Contemporary mapping results were 93.4% accurate overall (Kappa 0.9), with producer’s and user’s accuracies ≥85%. Classification results allowed partitioning mangroves in to ecologically meaningful, spectrally distinct strata, wherein field measurements facilitated estimating the first total carbon stocks for mangroves in Madagascar. Estimates suggest that higher stature closed-canopy mangroves have average total vegetation carbon values of 146.8 Mg/ha (±10.2) and soil organic carbon of 446.2 (±36.9), supporting a growing body of studies that mangroves are amongst the most carbon-dense tropical forests.
Healthy forests provide human communities with a host of important ecosystem services, including the provision of food, clean water, fuel, and natural medicines. Yet globally, about 13 million hectares of forests are lost every year, with the biggest losses in Africa and South America. As biodiversity loss and ecosystem degradation due to deforestation continue at unprecedented rates, with concomitant loss of ecosystem services, impacts on human health remain poorly understood. Here, we use data from the 2010 Malawi Demographic and Health Survey, linked with satellite remote sensing data on forest cover, to explore and better understand this relationship. Our analysis finds that forest cover is associated with improved health and nutrition outcomes among children in Malawi. Children living in areas with net forest cover loss between 2000 and 2010 were 19% less likely to have a diverse diet and 29% less likely to consume vitamin A-rich foods than children living in areas with no net change in forest cover. Conversely, children living in communities with higher percentages of forest cover were more likely to consume vitamin A-rich foods and less likely to experience diarrhea. Net gain in forest cover over the 10-year period was associated with a 34% decrease in the odds of children experiencing diarrhea (P5.002). Given that our analysis relied on observational data and that there were potential unknown factors for which we could not account, these preliminary findings demonstrate only associations, not causal relationships, between forest cover and child health and nutrition outcomes. However, the findings raise concerns about the potential short- and long-term impacts of ongoing deforestation and ecosystem degradation on community health in Malawi, and they suggest that preventing forest loss and maintaining the ecosystem services of forests are important factors in improving human health and nutrition outcomes.
Background: Establishing Protected Areas (PAs) is among the most common conservation interventions. Protecting areas from the threats posed by human activity will by definition inhibit some human actions. However, adverse impacts could be balanced by maintaining ecosystem services or introducing new livelihood options. Consequently there is an ongoing debate on whether the net impact of PAs on human well-being at local or regional scales is positive or negative. We report here on a systematic review of evidence for impacts on human well-being arising from the establishment and maintenance of terrestrial PAs.
Methods: Following an a priori protocol, systematic searches were conducted for evidence of impacts of PAs post 1992. After article title screening, the review was divided into two separate processes; a qualitative synthesis of explanations and meaning of impact and a review of quantitative evidence of impact. Abstracts and full texts were assessed using inclusion criteria and conceptual models of potential impacts. Relevant studies were critically appraised and data extracted and sorted according to type of impact reported. No quantitative synthesis was possible with the evidence available. Two narrative syntheses were produced and their outputs compared in a metasynthesis.
Results: The qualitative evidence review mapped 306 articles and synthesized 34 that were scored as high quality. The quantitative evidence review critically appraised 79 studies and included 14 of low/medium susceptibility to bias. The meta-synthesis reveals that a range of factors can lead to reports of positive and negative impacts of PA establishment, and therefore might enable hypothesis generation regarding cause and effect relationships, but resulting hypotheses cannot be tested with the current available evidence.
Conclusions: The evidence base provides a range of possible pathways of impact, both positive and negative, of PAs on human well-being but provides very little support for decision making on how to maximize positive impacts. The nature of the research reported to date forms a diverse and fragmented body of evidence unsuitable for the purpose of informing policy formation on how to achieve win-win outcomes for biodiversity and human well-being. To better assess the impacts of PAs on human well-being we make recommendations for improving research study design and reporting.
This review aims to contribute to the ongoing discussion about human health, global change, and biodiversity by concentrating on the relationships between forests and human health. This review gives a short overview of the most important health benefits that forests provide to humans, and the risks that forests may pose to human health. Furthermore, it discusses the future chal- lenges for the research on the links between forests and human health, and for delivering health through forests in practice. Forests provide enormous possibilities to improve human health conditions. The results of a vast amount of research show that forest visits promote both physical and mental health by reducing stress. Forests represent rich natural pharmacies by virtue of being enormous sources of plant and microbial material with known or potential medicinal or nutritional value. Forest food offers a safety net for the most vulnerable population groups in develop- ing countries, and healthy forest ecosystems may also help in regulation of infectious diseases. Utilizing forests effectively in health promotion could reduce public health care budgets and create new sources of income. Main challenges to delivering health through forests are due to ecosystem and biodiversity degradation, deforestation, and climate change. In addition, major implementation of research results into practice is still lacking. Inadequate implementation is partly caused by insufficient evidence base and partly due to the lack of policy-makers’ and practitioners’ awareness of the potential of forests for improving human health. This calls for strong cooperation among researchers, policy-makers, and practitioners as well as between different sectors, especially between health and environmental professionals.
High smoke concentrations in Equatorial Asia, primarily from land conversion to oil palm plantations, affect a densely populated region and represent a serious but poorly quantified air quality concern. Continued expansion of the oil palm industry is expected but the resulting population exposure to smoke is highly dependent on where this expansion takes place. We use the adjoint of the GEOS-Chem chemical transport model to map the sensitivity of smoke concentrations in major Equatorial Asian cities, and for the population-weighted region, to the locations of the fires. We find that fires in southern Sumatra are particularly detrimental, and that a land management policy protecting peatswamp forests in Southeast Sumatra would be of great air quality benefit. Our adjoint sensitivities can be used to immediately infer population exposure to smoke for any future fire emission scenario.
Protected areas (PAs) are a key strategy for protecting biological resources, but they vary considerably in their effectiveness, and are frequently reported as having negative impacts on local people. This has contributed to a divisive and unresolved debate concerning the compatibility of environmental and socioeconomic development goals. Elucidating the relationship between positive and negative social impacts and conservation outcomes of PAs is key for the development of more effective and socially just conservation. Here, we conduct a global analysis of how PAs affect the wellbeing of local people, the factors associated with these impacts, and crucially the relationship between PAs’ conservation and socioeconomic outcomes. Our results show that PAs reporting positive socioeconomic outcomes are more likely to report positive conservation outcomes. We find positive conservation and socioeconomic outcomes are more likely to occur when PAs adopt co-management regimes, empower local people, reduce economic inequalities and maintain cultural and livelihood benefits. While the strictest regimes of PA management attempt to exclude anthropogenic influences to achieve biological conservation objectives, our study provides evidence that PAs that explicitly integrate local people as stakeholders tend to be more effective at achieving joint biological conservation and socioeconomic development outcomes. Strict protection may be needed in some circumstances, yet our results demonstrate that conservation and development objectives can be synergistic and highlight management strategies that increase the probability of achieving win-win scenarios that maximize conservation performance and development outcomes of PAs.
Since the rise of modern humans, changes in demography, land use and frequent contact with wildlife and domesticated animals have created on- going opportunities for pathogen loss, gain, and evolution in the human population. Early transportation networks and population expansion cre- ated a world where many human-specific pathogens are now ubiquitous, yet zoonoses continue to emerge as humans encroach into the last remaining wild areas, increase livestock production, and plug into vast global trade net- works. Pathogens are exploiting almost any change in human ecology that provides new opportunities for transmission, the most recent being rampant use of antibiotics resulting in new multidrug-resistant pathogens. Public health advances have benefitted some, but others continue to suffer from pathogens long eradicated by developed nations. Generalities of pathogen occurrence aid in disease prediction, but a systemic approach incorporating ecology, biogeography, public health, and conservation biology is ultimately necessary to fully comprehend the changing geographic distributions of hu- man pathogens.
Reconsidering the relationship between human well-being and environmental quality is central for the management of wetlands and water resources and for public health itself. We propose an integrated strategy involving three approaches. The first is to make assessments of the ecosystem services provided by wetlands more routine. The second is to adopt the “settings” approach, most developed in health promotion, wherein wetlands are one of the settings for human health and provide a context for health policies. Finally, a layered suite of health issues in wetland settings is developed, including core requirements for human health (food and water); health risks from wetland exposures; and broader social determinants of health in wetland settings, including livelihoods and lifestyles. Together, these strategies will allow wetland managers to incorporate health impact assessment processes into their decisionmaking and to examine the health consequences of trade-offs that occur in planning, investment, development, and decisionmaking outside their direct influence.