Assessing health, livelihoods, ecosystem services and poverty alleviation in populous deltas

三角洲地区可能是最脆弱的沿海环境类型，其生态系统服务在未来几十年面临多重压力。这些压力包括，由于地面沉降、人口增长和三角洲内的城市化而导致的当地驱动因素，由于流域管理变化(例如上游土地使用和大坝建设)而导致的区域驱动因素，以及海平面上升等全球气候变化影响。河流三角洲的生态系统服务支持高人口密度，估计全球人口密度超过5亿，尤其集中在南亚、东亚和非洲。这些人中有很大一部分经历了极端的贫困，并因环境和生态压力和退化而面临严重的脆弱性。在接近或低于贫困边界的地区，经济的维持生计和现金要素往往严重依赖支撑生计的生态系统服务。要了解如何可持续地管理三角洲地区的生态系统服务，从而改善健康并减少贫穷和脆弱性，需要考虑所有这些压力及其复杂的相互作用。该提案旨在开发方法，以了解和描述生态系统服务变化的关键驱动因素，这些变化影响到世界人口众多的三角洲的环境和经济状况。这将通过分析生态系统服务的演变作用，探索变化对三角洲居民生计的影响，以及在面临未来几十年和未来的巨大不确定性的情况下，制定现在和未来将有益的管理和政策选择来完成。孟加拉国境内恒河-雅鲁藏布江-梅赫纳三角洲的广泛沿海边缘已被选为这项工作的试点研究区域。这是因为孟加拉国几乎完全位于世界上最大、最具活力的三角洲之一。它的特点是人口稠密的沿海低地，贫困严重，在很大程度上得到了自然生态系统的支持，如桑德巴恩(世界上最大的红树林)。由于许多发展中的城市，例如库尔纳和首都达卡，它面临着严重的发展压力。目前，人们对生态系统服务对贫困和生计的重要性知之甚少。这是由于物理驱动因素、环境压力和人类对压力的反应以及由此对生态系统的影响之间相互作用的复杂性。政府政策很少从生态系统服务的角度考虑，因此往往忽视了对其价值的全面概述。该项目旨在通过向决策者提供知识和工具，使他们能够评估政策决定对人民生计的影响，从而解决这一差距。为此，将在三角洲地区的下沉和海平面上升、土地退化和人口压力等变化的背景下，制定一种全面的方法，正式评估生态系统服务和贫困。这将在孟加拉国沿海地区进行测试和应用，并在其他人口稠密的三角洲进行概念性测试。

Delta regions are probably the most vulnerable type of coastal environment and their ecosystem services face multiple stresses in the coming decades. These stresses include, amongst others, local drivers due to land subsidence, population growth and urbanisation within the deltas, regional drivers due to changes in catchment management (e.g. upstream land use and dam construction), and global climate change impacts such as sea-level rise.The ecosystem services of river deltas support high population densities, estimated at over 500 million people globally, with particular concentrations in Southern and Eastern Asia and Africa. A large proportion of these people experience extremes of poverty and are severely exposed to vulnerability from environmental and ecological stress and degradation. In areas close to or below the poverty boundary, both subsistence and cash elements of the economy tend to rely disproportionately heavily on ecosystem services which underpin livelihoods.Understanding how to sustainably manage the ecosystem services in delta regions and thus improve health and reduce poverty and vulnerability requires consideration of all these stresses and their complex interaction. This proposal aims to develop methods to understand and characterise the key drivers of change in ecosystem services that affect the environment and economic status in the world's populous deltas. This will be done through analysis of the evolving role of ecosystem services, exploring the implications of changes for the livelihoods of delta residents, and developing management and policy options that will be beneficial now and in the future in the face of the large uncertainties of the next few decades and beyond.The extensive coastal fringe of the Ganges-Brahmaputra-Meghna Delta within Bangladesh has been selected as the pilot study area for this work. This is because Bangladesh is almost entirely located on one of the world's largest and most dynamic deltas. It is characterised by densely populated coastal lowlands with significant poverty, supported to a large extent by natural ecosystems such as the Sunderbahns (the largest mangrove forest in the world). It is under severe development pressure due to many growing cities, eg Khulna and the capital, Dhaka.At present the importance of ecosystems services to poverty and livelihoods is poorly understood. This is due to due to the complexity of interactions between physical drivers, environmental pressures and the human responses to stresses and the resultant impacts on ecosystems. Government policy rarely takes up the ecosystems services perspective and as a result an holistic overview of their value is often overlooked.This project aims to address this gap by providing policy makers with the knowledge and tools to enable them to evaluate the effects of policy decisions on people's livelihoods. This will be done by creating a holistic approach to formally evaluating ecosystems services and poverty in the context of changes such as subsidence and sea level rise, land degradation and population pressure in delta regions. This will be tested and applied in coastal Bangladesh and tested conceptually in other populous deltas.