The impact on human health of restoring degraded African drylands

这一多国项目旨在确定非洲萨赫勒地区大规模土地恢复的健康益处。我们将利用世界上最大的土地恢复努力-非洲绿色长城(GGW)倡议，作为一个自然实验系统。旱地拥有全球近40%的人口。GGW和目前在世界各地正在进行的其他类似的土地恢复努力，将重塑全球数十亿人的景观和生活体验。随着世界寻求应对和适应气候变化、生物多样性丧失和粮食安全的三重挑战，这样的恢复努力越来越被视为潜在的基于自然的解决方案。然而，目前，人类健康因素在包括GGW在内的恢复项目的设计和实施中扮演着非常小的角色。该项目旨在填补这一关键空白，以确保修复项目能够在实现其他目标的同时，最大限度地服务于人类健康。我们将使用跨越4个集成工作包的活动的新颖组合来实现这一点。简而言之，WP1将包括文献审查和社区协商，以开发一个反复完善的、对性别问题有敏感认识的逻辑模型，描述旱地恢复和人类健康之间的因果联系。这将通过帮助完善关键假设和确定次级健康结果的适当子集来指导该项目，以便在后续的WPS中进行评估。在WP2中，我们将对现有数据进行尽可能多的整理，以便GGW国家进行萨赫勒全村匹配的健康影响评估。要调查的主要结果将是儿童(0-59个月)的年龄体重z评分(WAZ)，作为衡量急性营养状况的指标。还将审议WP1产生的儿童和妇女的次要结果的一个子集，因为这是特别相关的。我们将比较有和没有GGW活动的社区之间的健康结果，以评估修复对健康的影响。WP3将是WPs1-2的后续行动，我们将在三个重点国家(冈比亚、塞内加尔、布基纳法索)收集初步数据，进行更有针对性、社区优先、村庄匹配的健康影响评估。根据我们目前对健康和环境恢复之间联系的理解，这些可能包括其他人体测量指标(例如，年龄身高z分数)，以及反映营养、感染和心理健康/幸福途径上的风险因素的结果。我们将再次把重点放在儿童和非怀孕妇女身上。一些次要结果需要从儿童身上收集生物样本进行实验室分析。后续抽样将提供有关季节性影响的信息，并有机会在有和没有GGW干预的小组之间比较12-14个月期间的儿童生长发育。WP4包括一套综合任务，旨在将健康影响评价的结果与指导设计和实施GGW的当前活动结合起来，并了解完成GGW对健康的作用和益处。由于到2030年实现其1亿公顷恢复旱地的目标的预计成本约为500亿美元，将健康影响(效益和成本)纳入现有决策支持工具以用于应用目的至关重要。我们将通过卫生经济评估、成本效益和权衡分析以及气候变化背景下的系统和情景建模等一系列步骤来实现这一点。在所有WPS中，我们的项目伙伴和科学指导委员会将进一步确保地方相关性，并简化从研究到实践的管道，增强影响。

This multi-country project aims to establish the health benefits of large-scale land restoration in Africa's Sahel region. We will leverage the Great Green Wall (GGW) of Africa initiative, the largest land restoration effort in the world, as a natural experimental system. Drylands host nearly 40% of the global population. The GGW and other similar land-restoration efforts currently underway around the world are set to reshape landscapes and the lived experiences of billions of people globally. Such restoration efforts are increasingly being regarded as potential 'Nature-based solutions' as the world seeks to confront and adapt to the triple challenges of climate change, biodiversity loss and food security.At present however, human health considerations play a very minor role in the design and implementation of restoration projects, including the GGW. This project aims to fill this critical gap, to ensure restoration projects can maximally serve human health alongside other objectives. We will use a novel combination of activities spanning 4 integrated work packages to do this. Briefly, WP1 will comprise a literature review and community consultations to develop an iteratively refined, gender-sensitive logic model describing the causal linkages between dryland restoration and human health. This will guide the project by helping to refine key hypotheses and identify a suitable subset of secondary health outcomes to be evaluated in subsequent WPs. In WP2 we will collate as much existing data as possible for GGW countries to conduct a Sahel-wide village-matched health impact evaluation. The primary outcome to be investigated will be weight-for-age z score (WAZ) of children (0-59 months) as a measure of acute nutritional status. A subset of secondary outcomes in children and women emerging from WP1 as of particular relevance will also be considered. We will compare health outcomes between communities with and without GGW activities to evaluate the health impacts of restoration. WP3 will be a follow-up of WPs1-2 in which we will conduct a more targeted, community-prioritised, village-matched health impact evaluation with primary data collection in three focal countries (The Gambia, Senegal, Burkina Faso). Based on our current understanding of the linkages between health and environmental restoration, these are likely to include other anthropometric measures (e.g., height-for-age z score, HAZ), and outcomes reflecting risk factors on the nutrition, infection and mental health / well-being pathways. We will again focus on children and non-pregnant women. Some secondary outcomes require collection of biological samples from children for laboratory analysis. Follow-up sampling will give information on seasonal effects and an opportunity to compare child growth over a 12-14 month period between groups with and without GGW interventions. WP4 comprises a set of integrating tasks aimed at marrying the results of the health impact evaluations with current activities guiding the design and implementation of the GGW and understanding the role of and benefits to health of completing the GGW. With an anticipated cost of around $50 billion to reach its 100 million hectare target of restored drylands by 2030, it is essential for health impacts (benefits and costs) to be brought into existing decision-support tools for applied purposes. We will do this via a combination of steps from health economic evaluation, cost-benefit and trade-off analysis, and systems and scenario modelling in the context of a changing climate. In all WPs, our Project Partners and Scientific Steering Committee will further ensure local relevance and streamline the research-to-practice pipeline, enhancing impact.