Efficiency of Biological Utilization of Micronutrients by Forests Species in Hypoxerophytic Caatinga

ABSTRACT The study aimed to estimate the concentrations and efficiency of biological utilization of Cu, Fe, Zn, and Mn and the leaf biomass of ten species in a hypoxerophytic Caatinga fragment, aiming to contribute to a more adequate choice of species for reforestation programs in the Brazilian Caatinga. The leaves of three trees of each species were sampled and the concentration of micronutrients was determined, estimating their content and efficiency of biological utilization. The efficiency of biological utilization followed the decreasing order: Mn > Cu > Zn > Fe. Jatropha mollissima and Spondias tuberosa were less efficient in the use of Fe and Senegalia paniculata and Croton blanchetianus, in the use of Zn. However, Piptadenia stipulacea and Mimosa ophthalmocentra were very efficient in using Fe and Mn. The nutritional efficiency of the species can serve as a criterion for choice of species in forest restoration programs.

摘要 本研究旨在对旱生性卡廷加（Caatinga）群落片段中10个物种的铜（Cu）、铁（Fe）、锌（Zn）与锰（Mn）浓度、生物利用效率及其叶片生物量进行估算，以期为巴西卡廷加地区的造林项目提供更适宜的物种选择参考。研究采集了各物种3株林木的叶片样本，测定其微量营养元素浓度，并据此估算元素含量与生物利用效率。生物利用效率由高到低依次为：锰（Mn）> 铜（Cu）> 锌（Zn）> 铁（Fe）。Jatropha mollissima与Spondias tuberosa对铁（Fe）的利用效率较低，Senegalia paniculata和Croton blanchetianus则对锌（Zn）的利用效率不佳。然而，Piptadenia stipulacea与Mimosa ophthalmocentra对铁（Fe）和锰（Mn）的利用效率极高。该类物种的营养利用效率可作为森林恢复项目中物种选择的参考标准。