Alnus acuminata Kunth. (alnus) is widely used in agroforestry systems across the globe and is believed to provide multiple ecosystem services; however, evidence is lacking in agroforestry literature to support the perceived benefits, particularly in Rwanda. To understand carbon sequestration potential and other benefits of alnus, a household survey, tree inventory and destructive sampling were conducted in north-western Rwanda. Over 75% of the respondents had alnus trees in their farms. The trees provide stakes for climbing beans, firewood and timber. They also improve soil fertility and control soil erosion. Farmers had between 130 and 161 alnus trees per hectare with an average height of 7.7 ± 0.59 m and diameter at breast height of 16.3 ± 1.39 cm. The largest biomass proportion was found in stems (70.5%) while branches and leaves stock about 16.5 and 13% of the total biomass, respectively. At farm level, aboveground biomass of alnus trees was estimated to be 27.2 ± 0.7 Mg ha⁻¹ representing 13.6 Mg of carbon (C) per hectare. Biomass carbon increased with tree size, from 7.1 ± 0.2 Mg C ha⁻¹ in 3 years old trees to 34.4 ± 2.2 Mg C ha⁻¹ in 10 years old trees. The converse was observed with elevation; biomass carbon decreased with increasing elevation from 21.4 ± 1.29 Mg C ha⁻¹ at low (2011–2110 m) to 9.6 ± 0.75 Mg C ha⁻¹ in the high elevation (> 2510 m). In conclusion, alnus agroforestry significantly contributes to carbon sequestration, although the magnitude of these benefits varies with tree age and elevation. Planting alnus trees on farms can meet local needs for stakes for climbing beans, wood and soil fertility improvement, as well as the global need for regulation of climate change.

Al木昆斯。（alnus）在全球农林业系统中广泛使用，被认为可以提供多种生态系统服务；但是，农林业文献缺乏证据来支持人们所感知到的利益，特别是在卢旺达。为了了解碳固存的潜力和肛门的其他好处，在卢旺达西北部进行了一项家庭调查，树木清单和破坏性采样。超过75％的受访者在其农场中种植了芦荟树。树木为攀登豆类，木柴和木材提供了树桩。它们还可以提高土壤肥力并控制土壤侵蚀。农民每公顷有130到161棵艾露斯树，平均高度为7.7±0.59 m，胸径为16.3±1.39 cm。在茎中发现最大的生物量比例（70.5％），而树枝和叶子的存量约为16。分别占总生物量的5％和13％。在农场一级，针叶树的地上生物量估计为27.2±0.7 Mg ha^-1代表每公顷13.6 Mg碳（C）。生物量碳随树的大小而增加，从3年龄树木的7.1±0.2 Mg C ha ^-1增加到10年龄树木的34.4±2.2 Mg C ha ^-1。相反，观察到海拔升高。随着海拔的升高，生物量碳含量从低（2011-2110 m）的21.4±1.29 Mg C ha ^-1降低到高海拔（> 2510 m）的9.6±0.75 Mg C ha ^-1。总之，阿努斯农用林业在固碳方面发挥了重要作用，尽管这些收益的幅度随树龄和海拔的高低而变化。在农场上种植艾努斯树可以满足当地对攀爬豆树桩的需求，改善木材和土壤肥力以及全球调节气候变化的需求。