Managing ecosystem services to reduce poverty and vulnerability in East African coffee landscapes

咖啡是全世界数百万小农生计的基础。在东非国家，60-100%的咖啡是小农种植的，是个体农民的主要收入来源，该地区咖啡出口收入总额超过10亿美元，咖啡是政府改善生计和减少贫困的关键政策工具。对于卢旺达和布隆迪等东非国家来说，咖啡占出口收入的50%以上，甚至对于乌干达等较大的经济体来说，咖啡也占10%。对一种商品的高度依赖增加了对价格波动和其他市场风险的脆弱性（如1990年代/2000年代初的价格暴跌）。由于许多咖啡小农很穷，无法进行资本投资或通过无机投入提高产量，他们在作物生产中严重依赖畜牧技能和生态系统服务（如土壤健康、授粉、虫害控制）。咖啡不仅依赖于这些服务，而且由于其战略高地位置，提供重要的环境服务，通常邻近该地区的森林。主要服务包括在景观和区域范围内控制土壤和水的流动，以及在树木被纳入咖啡景观的情况下，森林生境的连通性。此外，一些趋势正在威胁咖啡生计。全球环流模型对东非的气候变化做出了高度可变的预测，咖啡对温度和降水很敏感。国家政策正在促进使用无荫杂交咖啡，这种咖啡生长旺盛，产量高于传统咖啡类型，而越来越多地使用单一作物（例如在肯尼亚，单一作物占产量的40%）使农民进一步面临天气或虫害引起的收入风险。咖啡起源于森林，树荫下的产量可能较低，但质量往往较高，树的寿命较长。遮荫咖啡还提供重要的土壤保持和水文生态系统服务。单一作物的使用增加了径流和土壤流失，从而降低了土壤质量和产量。农民们陷入了一个循环，土壤质量继续逐年下降，改善生计的政策实际上可能使他们的长期生活更糟。提案小组先前的工作发现，咖啡系统中的农民没有充分利用某些生态系统服务，因此生产和由此产生的收入低于可能达到的水平。事实上，一些简单的管理方法（如适当管理休耕地）已被证明可以提高授粉等服务水平，从而为农民带来直接的经济利益。由于该地区将受到未来气候和土地利用变化的影响，因此必须了解如何在现在和未来优化管理服务，并确定未来的新型种植系统。我们建议制定一项研究方案，旨在改善东非咖啡系统现在和未来气候变化下的管理方式，以增加农民的收入，改善农村生计。利用研讨会和现有知识和数据的审查，并开发新的研究工具，我们将设计一个活动方案，将汇集来自生物，经济和社会科学的各种技能，使我们能够正确理解系统的所有组成部分如何相互作用和相互影响。通过了解生态系统服务如何影响咖啡生产，我们可以开发知识，以便更好地管理这些服务，从而改善农民的生计。这一过程的一部分是确保将科学发现转化为可用于直接向农民提供如何改善咖啡种植管理的建议的形式，并帮助决策者制定新的政策和支持系统，以帮助在更大范围内指导农民。

Coffee underpins the livelihoods of millions of smallholder farmers worldwide. In East African countries, 60-100% of coffee is smallholder grown and a major source of income for individual farmers, Coffee export earnings total over 1 billion US $ in the region and coffee is a key policy tool for governments to improve livelihoods and reduce poverty. For East African countries such as Rwanda and Burundi, coffee forms >50% of export earnings and even for larger economies in Uganda, for example, it makes up 10%. High dependency on one commodity increases vulnerability to fluctuating prices and other market risks (eg slumps in prices in the 1990's/early 2000s). As many smallholder coffee farmers are poor and unable to undertake capital investment or improve yields through inorganic inputs, they rely heavily on husbandry skills and ecosystem services (e.g. soil health, pollination, pest regulation) for crop production. Coffee not only depends on these services but provides important environmental services because of its strategic upland location, often neighbouring what forest remains in the region. The key services include the control of soil and water movement at landscape and regional scales and, where trees are incorporated in coffee landscapes, connectivity of forest habitat. A number of trends are furthermore threatening coffee livelihoods. Global circulation models produce highly variable climate change predictions for Eastern Africa and coffee is sensitive to temperature and precipitation. National policies are promoting the use of non-shade hybrid coffee that is vigorous and produces higher yields than traditional coffee types, while the increasing use of monocropping (e.g. in Kenya it is 40% of production) further exposes farmers to weather or pest-induced income risks. Coffee originated in forests and yields under shade may be lower but quality tends to be higher and the tree lifespan longer. Shaded coffee also provides important soil conservation and hydrological ecosystem services. The use of monocrops increases run off and soil loss, thus reducing soil quality and yields. Farmers are then trapped in a loop where soil quality continues to fall year-on-year and policies to improve livelihoods may actually make them worse off in the long-term. Previous work by the proposal team has found that some of ecosystem services are not being fully exploited by farmers in coffee systems and so production, and the income generated from it, is below levels which could be achieved. Indeed, some simple management practices (eg managing fallow land appropriately) have been shown to enhance services like pollination to levels where they have a direct economic benefit to farmers. As the region will be influenced by future climate and land use change it is important to understand how to optimally manage services now and in the future, and identify novel cropping systems for the future. We propose to develop a research programme which aims to improve the way coffee systems in East Africa are managed now and under future climate change so that the income farmers receive is increased and rural livelihoods improved. Using workshops and reviews of existing knowledge and data, and developing new research tools, we will design a programme of activities which will bring together diverse skills from biological, economic, and social sciences so that we can properly understand how all the components of the system interact and affect each other. By understanding how ecosystem services affect coffee production we can develop knowledge to allow better management of these services so that livelihoods of farmers are improved. One part of this process is making sure that scientific findings are translated into forms which can be used to directly advise farmers on how to improve the management of coffee growing and also help decision makers develop new policies and support systems to help guide farmer at a wider scale.