Caldeira Cecilio F, Lima Madson O, Ramos Silvio J, Gastauer Markus
Instituto Tecnológico Vale, Rua Boaventura da Silva 955, Belém CEP 66055-090, Pará, Brazil.
Plants (Basel). 2021 Apr 22;10(5):849. doi: 10.3390/plants10050849.
Native species may have adaptive traits that are advantageous for overcoming the adverse environmental conditions faced during the early stages of mine land rehabilitation. Here, we examined the nitrogen (N) growth responses of two native perennial grasses ( and ) from in nutrient-poor iron mining substrates. We carried out vegetative propagation and recovered substantial healthy tillers from field-collected tussocks of both species. These tillers were cultivated in mining substrates at increasing N levels. The tillering rates of both species increased with the N application. Nonetheless, only in did the N application result in significant biomass increase. Such growth gain was a result of changes in leaf pigment, stomatal morphology, gas exchanges, and nutrients absorption that occurred mainly under the low N additions. Reaching optimum growth at 80 mg N dm, these plants showed no differences from those in the field. Our study demonstrates that an input of N as fertilizer can differentially improve the growth of native grasses and that plants are able to deposit high quantities of carbon and protect soil over the seasons, thus, making them promising candidates for restoring nutrient cycling, accelerating the return of other species and ecosystem services.
本地物种可能具有适应性特征，有利于克服矿区土地复垦早期面临的不利环境条件。在此，我们研究了两种来自[具体地点]的本地多年生草本植物（[植物名称1]和[植物名称2]）在营养贫瘠的铁矿开采基质中对氮（N）的生长响应。我们进行了营养繁殖，并从野外采集的两种植物的草丛中获得了大量健康的分蘖。这些分蘖在氮水平不断增加的采矿基质中进行栽培。两种植物的分蘖率均随施氮量增加而提高。然而，只有[植物名称1]施氮导致生物量显著增加。这种生长增加是叶片色素、气孔形态、气体交换和养分吸收变化的结果，这些变化主要发生在低氮添加条件下。这些植物在80毫克氮/平方分米时达到最佳生长，与野外植物没有差异。我们的研究表明，作为肥料输入氮可以不同程度地改善本地草本植物的生长，并且[植物名称1]植物能够在整个季节积累大量碳并保护土壤，因此，使其成为恢复养分循环、加速其他物种回归和生态系统服务的有前景的候选植物。
