Effects of the invasive clam Corbicula fluminea (Müller, 1774) on an estuarine microbial community Adriana Novais a, ⁎, Allan T. Souza b , Martina Ilarri c,d , Cláudia Pascoal a , Ronaldo Sousa a,c a CBMA — Centre of Molecular and Environmental Biology, Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal b CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Polo dos Açores — Departamento de Biologia da Universidade dos Açores, 9501-801 Ponta Delgada, Portugal c CIIMAR/CIMAR — Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Rua dos Bragas 289, P 4050-123 Porto, Portugal d ICBAS-UP — Abel Salazar Biomedical Sciences Institute, University of Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal HIGHLIGHTS • C. fluminea is well recognized for its in- vasive behavior and ecological impacts. • We tested the effects of C. fluminea on an microbial community. • The presence of living C. fluminea stim- ulated fungal biomass and bacterial di- versity. • Bioturbation by C. fluminea is the poten- tial main mechanism explaining our re- sults. GRAPHICAL ABSTRACT abstract article info Article history: Received 8 April 2016 Received in revised form 23 May 2016 Accepted 24 May 2016 Available online xxxx Editor: D. Barcelo The Asian clam Corbicula fluminea (Müller, 1774) is well recognized for its invasive behavior and high ecological and economic impacts, being classified as one of the 100 worst invasive alien species (IAS) in Europe. In this study, we performed a manipulative experiment under natural conditions to assess the effects of C. fluminea on sediments biochemistry and on the structure of an estuarine microbial (fungi and bacteria) community. We placed 5 treatments (control, rock, closed, live and open) for 2 months in the Minho estuary (NW Iberian Penin- sula). No differences were detected between treatments regarding the values of carbon (C), nitrite (NO 2 - ), am- monium (NH 4 + ), phosphate (PO 4 3- ) and calcium (Ca) in the sediments; however, potassium (K) had higher values in the open treatment. Furthermore, we found that the presence of live C. fluminea stimulated fungal bio- mass (but not diversity) and bacterial diversity. Bioturbation activities by C. fluminea are possibly the main mech- anism explaining these results; however, other factors such as the presence of other macroinvertebrate species and/or production of feces and pseudofeces by C. fluminea cannot be excluded. To our knowledge, this is the first manipulative experiment under natural conditions that clearly shows the effects of C. fluminea on an estua- rine microbial community. Given the widespread distribution of this IAS and the paucity of quantitative Keywords: Invasive bivalves Bacteria Fungi Minho estuary Nutrients Science of the Total Environment xxx (2016) xxx–xxx ⁎ Corresponding author. E-mail address: adriana.novais1990@gmail.com (A. Novais). STOTEN-20071; No of Pages 8 http://dx.doi.org/10.1016/j.scitotenv.2016.05.167 0048-9697/© 2016 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv Please cite this article as: Novais, A., et al., Effects of the invasive clam Corbicula fluminea (Müller, 1774) on an estuarine microbial community, Sci Total Environ (2016), http://dx.doi.org/10.1016/j.scitotenv.2016.05.167