| Abstract | The natural high productivity of river lagoons has always attracted human activities of high economic value such as aquaculture. Notwithstanding, these environments are also prone to contamination, excessive organic enrichment and hypoxic/anoxic events due to the synergy between natural (e.g. fluctuations of oxygen, temperature and salinity) and anthropogenic factors (e.g. accumulation of pollutants carried by the river). In order to minimize any economic loss and potential risk for human health, river lagoons are kept under surveillance by means of monitoring campaigns that rarely include foraminifera and nematoda despite their suitability as ecological indicators. In May 2016, these two assemblages were investigated within the framework of the project RITMARE in four lagoons of the Po Delta system (Adriatic Sea) in terms of taxonomic composition, biodiversity and biological traits. Dominated by a few tolerant taxa (Ammonia tepida and Haynesina germanica for foraminifera; Daptonema, Tershellingia and Sabatieria for nematoda), both assemblages seemed adapted to conditions of environmental instability mainly ascribable to natural disturbance factors rather than to anthropogenic contamination, as indicated by the DISTLM outputs. Furthermore, the stochastic occurrence of abnormal tests and the presence of numerous organisms in subsurface sediment levels confirmed a limited effect of synthetic organic compounds (e.g. aromatic hydrocarbons and polybrominated diphenyl ethers) and trace metals on foraminifera. Focusing on nematoda, the assemblage seemed more sensitive in reflecting the peculiar environmental conditions of each lagoon and the degree of confinement, as indicated by the significant intra- and inter-lagoon variability detected for the majority of the tested metrics. In particular the significantly less biodiverse assemblage dominated by r-strategist (i.e. pioneer) organisms at the inner and middle stations of Scardovari may represent the nematoda response to recent hypoxic/anoxic conditions that often occur in the inner areas of this lagoon because of its low water renewal. Both assemblages showed to be suitable for the implementation of monitoring programs; from the study of foraminifera, a relatively low chemical contamination was inferred while, from that of nematodes, recent events of oxygen deficiency were detectable. |
| Text | 402545 2019 10.1016/j.ecss.2019.02.039 Scopus 2 s2.0 85062398210 River lagoon; Foraminifera; Nematoda; Contamination; Hypoxia; Monitoring Influence of natural and anthropogenic disturbances on foraminifera and free living nematodes in four lagoons of the Po delta system Franzo A.; Asioli A.; Roscioli C.; Patrolecco L.; Bazzaro M.; Del Negro P.; Cibic T. Sezione di Oceanografia, Istituto Nazionale di Oceanografia e di Geofisica Sperimentale OGS, via A. Piccard 54, Trieste, I 34151, , Italy; Institute of Marine Science, National Research Council ISMAR CNR , via P. Gobetti 101, Bologna, I 40129, , , Italy; Water Research Institute, National Research Council IRSA CNR , Via Del Mulino 19, Brugherio, I 20861, , , Italy; Water Research Institute, National Research Council IRSA CNR , Via Del Mulino 19, Brugherio, I 20861, , , Italy; Water Research Institute, National Research Council IRSA CNR , Via Salaria km 29,300, Monterotondo, Rome, I 00015, , , Italy; Water Research Institute, National Research Council IRSA CNR , Via Salaria km 29,300, Monterotondo, Rome, I 00015, , , Italy; Dipartimento di Scienze fisiche, della Terra e dell ambiente, Universita degli Studi di Siena, Strada Laterina, Siena, 53100, , Italy The natural high productivity of river lagoons has always attracted human activities of high economic value such as aquaculture. Notwithstanding, these environments are also prone to contamination, excessive organic enrichment and hypoxic/anoxic events due to the synergy between natural e.g. fluctuations of oxygen, temperature and salinity and anthropogenic factors e.g. accumulation of pollutants carried by the river . In order to minimize any economic loss and potential risk for human health, river lagoons are kept under surveillance by means of monitoring campaigns that rarely include foraminifera and nematoda despite their suitability as ecological indicators. In May 2016, these two assemblages were investigated within the framework of the project RITMARE in four lagoons of the Po Delta system Adriatic Sea in terms of taxonomic composition, biodiversity and biological traits. Dominated by a few tolerant taxa Ammonia tepida and Haynesina germanica for foraminifera; Daptonema, Tershellingia and Sabatieria for nematoda , both assemblages seemed adapted to conditions of environmental instability mainly ascribable to natural disturbance factors rather than to anthropogenic contamination, as indicated by the DISTLM outputs. Furthermore, the stochastic occurrence of abnormal tests and the presence of numerous organisms in subsurface sediment levels confirmed a limited effect of synthetic organic compounds e.g. aromatic hydrocarbons and polybrominated diphenyl ethers and trace metals on foraminifera. Focusing on nematoda, the assemblage seemed more sensitive in reflecting the peculiar environmental conditions of each lagoon and the degree of confinement, as indicated by the significant intra and inter lagoon variability detected for the majority of the tested metrics. In particular the significantly less biodiverse assemblage dominated by r strategist i.e. pioneer organisms at the inner and middle stations of Scardovari may represent the nematoda response to recent hypoxic/anoxic conditions that often occur in the inner areas of this lagoon because of its low water renewal. Both assemblages showed to be suitable for the implementation of monitoring programs; from the study of foraminifera, a relatively low chemical contamination was inferred while, from that of nematodes, recent events of oxygen deficiency were detectable. 220 Published version http //www.scopus.com/inward/record.url eid=2 s2.0 85062398210 partnerID=q2rCbXpz Influence of natural and anthropogenic disturbances on foraminifera and free living nematodes 1_s2_0_S0272771418309715_main.pdf Articolo in rivista Academic Press in association with the Estuarine and Brackish water Sciences Association, 0272 7714 Estuarine, coastal and shelf science Print Estuarine, coastal and shelf science Print Estuar., coast. shelf sci. Print Estuarine, coastal and shelf science. Print luisa.patrolecco PATROLECCO LUISA alessandra.asioli ASIOLI ALESSANDRA claudiogiovanni.roscioli ROSCIOLI CLAUDIO GIOVANNI |
