An estimated 3.4 million hectares of cocoa and 9.7 million hectares of coffee are cultivated, globally, under shade trees, i.e. in agroforestry systems. Shade canopies are characterized in terms of tree density (N, trees ha⁻¹), tree basal area (G, m² ha⁻¹) and percent canopy cover (%Cov). N, G and %Cov are named shade canopy density variables (SCDV). The use of these SCDV has two important limitations: (1) different combinations of values of the three SCDV variables generate very different shade tree stands (hence very different shading levels), and (2) Additional factors modify shading under shade canopies with constant SCDV values. This article uses the software ShadeMotion (www.shademotion.net) to show how 24 different, simple, even-sized, mono-layered, Cordia alliodora shade canopies with constant N, G and %Cov display significantly different shade levels and temporal patterns of shading depending on tree stem and crown diameter ratios, tree height, spatial planting configurations (square, random and alleys) and leaf fall patterns. A minimum set of variables capable of providing a more accurate description of the shading characteristics of a cocoa or coffee shade canopy is proposed. Our findings can shed light on the current debate on the pros and cons of the definitions of cocoa agroforestry used by chocolate and certification companies, governments, non-governmental organizations, and donors, especially in West and Central Africa. In this article, emphasis is given to cocoa, but the analysis, results and conclusions are equally applicable to coffee agroforestry systems.

全球估计有 340 万公顷可可和 970 万公顷咖啡种植在遮荫树下，即农林复合系统中。遮阳冠层以树木密度（N，树木 ha⁻¹）、树木断面积（G，m² ha⁻¹）和冠层覆盖百分比（%Cov）。 N、G 和 %Cov 被命名为遮荫冠层密度变量 (SCDV)。这些 SCDV 的使用有两个重要的限制：(1) 三个 SCDV 变量值的不同组合会产生非常不同的遮荫树林（因此遮荫级别也非常不同），以及 (2) 其他因素会修改具有恒定 SCDV 的遮荫树冠下的遮荫价值观。本文使用ShadeMotion软件（www.shademotion.net）展示24种不同的、简单的、大小均匀的、单层的Cordia alliodora阴影如何具有恒定 N、G 和 %Cov 的树冠显示出显着不同的遮荫级别和遮荫时间模式，具体取决于树干和树冠直径比率、树高、空间种植配置（方形、随机和小巷）和落叶模式。提出了能够更准确地描述可可或咖啡遮荫罩的遮光特性的最小变量集。我们的研究结果可以揭示当前关于巧克力和认证公司、政府、非政府组织和捐助者所使用的可可农林业定义的利弊的争论，特别是在西非和中非。本文重点关注可可，但分析、结果和结论同样适用于咖啡农林复合系统。