我们表征了TillandsiafasciculataSw的元素以及C和N稳定同位素组成。,提兰西亚·巴比西亚·舒特。&Schult.f.和Tillandsiarecurvata(L.)L.在Cienfuegos(古巴)收集的样本。结果表明,S的富集因子较高,Hg,Cd,Pb,P,Zn,Cu,Mo,所有Tillandsia物种中的Sb和Ca,指示来自当地人为活动的投入(道路交通,工业和水泥生产)。在这三个物种中,碳浓度和δ13C在38.3-47.7%和-20.4至-13.4‰之间变化,分别。δ13C在城市/工业区显示出与干湿期和更多13C耗尽值的季节性依赖性,与人为排放的输入相一致。氮浓度(0.4-1.3%)和δ15N值(-9.9-4.4‰)在这三个物种中表现出较大的变化,并且呈正相关。递归T.中最正的δ15N(-0.2-4.4‰)归因于工业活动和道路交通的贡献。事实上,在道路交通量较高的地点,δ15N和总氮(TN)值均增加,并与典型的道路交通和工业示踪剂显着相关。最后,我们从轮回中的N含量计算出平均总氮沉积速率为4.4±2.3kgha-1a-1,类似于通过现场测量在该区域确定的现有值,但高于全球陆地平均水平。
We characterized the elemental and C and N stable isotope compositions of Tillandsia fasciculata Sw., Tillandsia balbisiana Schult. & Schult.f. and Tillandsia recurvata (L.) L. samples collected in Cienfuegos (Cuba). Results showed high enrichment factors for S, Hg, Cd, Pb, P, Zn, Cu, Mo, Sb and Ca in all Tillandsia species, indicating inputs from local anthropogenic activities (road traffic, industries and cement production). Carbon concentrations and δ13C varied from 38.3-47.7 % and -20.4 to -13.4 ‰ within the three species, respectively. δ13C showed seasonal dependence with the dry and wet periods and more 13C-depleted values in urban/industrial areas, coherent with the input of anthropogenic emissions. Nitrogen concentrations (0.4-1.3 %) and δ15N values (-9.9-4.4 ‰) exhibit larger variations and are positively correlated in the three species. The most positive δ15N in T. recurvata (-0.2-4.4 ‰) are attributed to contributions from industrial activities and road traffic. In fact, both δ15N and total nitrogen (TN) values increase in sites with higher road traffic and show significant correlations with typical road traffic and industrial tracers. Finally, we calculate an average total nitrogen deposition rate of 4.4 ± 2.3 kg ha-1 a-1 from N content in T. recurvata, similar to the existing values determined in the region by field measurements, but higher than the global terrestrial average.