Soil fertility management and N-fixing species can support the ecosystem-level restoration of disrupted biogeochemical cycles in tropical degraded environments. However, the effectiveness of N-fixers during tropical forest restoration remains unclear. We hypothesized that tree legumes adjust growth, nonstructural carbohydrate allocation and foliar nutrients under different fertilization regimes. We compared the following six tree legume species: three native nonfixers (Cenostigma, Senna and Dipteryx), two native N-fixers (Clitoria and Inga) and an introduced N-fixer (Acacia). Twenty-four months after the experiment was established, fertilized plants increased growth rates and starch allocation to leaves, whereas unfertilized plants primarily increased their biomass and starch allocation to roots. The greater tolerance to nutrient deficiency of the Acacia than other native tree legumes was due to Acacia’s ability to adjust carbohydrate pools. N-fixers adjusted the shoot-to-root ratio and soluble sugar allocation to leaves, increasing biomass growth. The three N-fixing species were especially suitable for restoration because Acacia had tolerance of nutrient deficiencies, Clitoria and Inga had fast growth and biomass production. Hence, fertilization management and N-fixing species may have a considerable impact on C stocks in different plant compartments. Overall non-structural carbohydrate adjustments influence growth responses of species, especially the ratio between leaf and root tissues. Our findings suggest that this aspect should be considered as a tree species selection criterion for forest restoration programs in the Amazon region.

土壤肥力管理和固氮物种可以支持热带退化环境中破坏的生物地球化学循环的生态系统级恢复。然而，在热带森林恢复过程中固氮剂的有效性仍不清楚。我们假设树木豆类在不同的施肥制度下会调节生长，非结构性碳水化合物的分配和叶面养分。我们比较了以下六种豆科植物物种：三种天然非固色剂（Cenostigma，Senna和Dipteryx），两种天然N固色剂（Clitoria和Inga）和引入的N固色剂（Acacia））。建立实验后的24个月，受精植物提高了生长速度和淀粉向叶片的分配，而未受精植物则主要提高了生物量和淀粉对根的分配。相思树比其他本地豆类植物对营养缺乏症的耐受性更高，这是由于相思树具有调节碳水化合物库的能力。氮固定剂可调节枝根比和可溶性糖在叶片中的分配，从而增加生物量的生长。这三种固氮菌种特别适合于恢复，因为相思树具有耐营养缺乏的能力，Clitoria和Inga具有快速的增长和生物质生产。因此，施肥管理和固氮菌种可能对不同植物区室的碳库产生相当大的影响。总体的非结构性碳水化合物调节会影响物种的生长反应，尤其是叶和根组织之间的比例。我们的研究结果表明，这一方面应被视为亚马逊地区森林恢复计划的树种选择标准。