As both coffee quality and sustainability become increasingly important, there is growing interest in understanding how ecological quality affects coffee quality. Here we analyze, for the first time, the state of evidence that ecological quality, in terms of biodiversity and ecosystem functions, impacts the quality of Coffea arabica and C. canephora, based on 78 studies. The following ecosystem functions were included: pollination; weed, disease, and pest control; water and soil fertility regulation. Biodiversity was described by the presence, percentage, and diversity of shade trees. Coffee quality was described by the green bean physical characteristics, biochemical compounds, and organoleptic characteristics. The presence and diversity of shade trees positively impacted bean size and weight and reduced the percentage of rejected beans, but these observations were not consistent over different altitudes. In fact, little is known about the diversity of shade trees and their influence on biochemical compounds. All biochemical compounds varied with the presence of shade, percentage of shade, and elevation. Coffee beans from more diverse tree shade plantations obtained higher scores for final total organoleptic quality than simplified tree shade and unshaded plantations. Decreasing ecological quality diminished ecosystem functions such as pollination, which in turn negatively affected bean quality. Shade affected pests and diseases in different ways, but weeds were reduced. High soil quality positively affected coffee quality. Shade improved the water use efficiency, such that coffee plants were not water stressed and coffee quality was improved. While knowledge on the influence of shade trees on overall coffee quality remains scarce, there is evidence that agroecosystem simplification is negatively correlated with coffee quality. Given global concerns about biodiversity and habitat loss, we recommend that the overall definition of coffee quality include measures of ecological quality, although these aspects are not always detectable in certain coffee quality characteristics or the final cup.

随着咖啡质量和可持续性变得越来越重要，人们越来越有兴趣了解生态质量如何影响咖啡质量。在这里，我们首次分析了生态质量在生物多样性和生态系统功能方面影响小粒咖啡和C. canephora质量的证据状态，基于 78 项研究。包括以下生态系统功能：授粉；杂草、疾病和害虫防治；水土肥力调节。生物多样性通过遮荫树的存在、百分比和多样性来描述。咖啡品质由生豆的物理特性、生化成分和感官特性来描述。遮荫树的存在和多样性对豆子的大小和重量产生了积极影响，并降低了被拒绝的豆子的百分比，但这些观察结果在不同海拔高度并不一致。事实上，人们对遮荫树的多样性及其对生化化合物的影响知之甚少。所有生化化合物都随着阴影的存在、阴影的百分比和海拔而变化。与简化的树荫种植园和无树荫种植园相比，来自更多样化树荫种植园的咖啡豆在最终总体感官质量方面获得了更高的分数。生态质量下降会削弱授粉等生态系统功能，进而对豆类质量产生负面影响。阴影以不同的方式影响病虫害，但杂草减少了。高土壤质量对咖啡质量有积极影响。树荫提高了水分利用效率，使咖啡树不受水分胁迫，咖啡品质得到改善。虽然关于遮荫树对整体咖啡质量的影响的知识仍然很少，但有证据表明农业生态系统的简化与咖啡质量呈负相关。鉴于全球对生物多样性和栖息地丧失的担忧，