WETLANDS BIODIVERSITY AND PROCESSES Mitigation of herbicide runoff as an ecosystem service from a constructed surface flow wetland S. E. Pappalardo . S. Otto . V. Gasparini . G. Zanin . M. Borin Received: 2 March 2015 / Revised: 15 May 2015 / Accepted: 13 June 2015 Ó Springer International Publishing Switzerland 2015 Abstract Ecosystem services provided by wetland systems presently play a pivotal role in intensive cropland as water purification from agricultural pol- lution. A field trial was conducted in 2014 to evaluate herbicide runoff reduction and retention using a 0.32 ha constructed surface flow wetland (CSFW) at the outlet of a 6 ha agricultural basin. To simulate an extreme pulse contamination, the CSFW was flooded with a runoff contaminated with metolachlor, and terbuthylazine and two other subsequent floods with pure water were applied 21 and 65 days later. Results show that the CSFW can reduce runoff concentration of metolachlor and terbuthylazine by a factor of 45–80 even in extreme flooding conditions. Herbicides retention in the CSFW was reversible, and the second and third floods mobilized 14–31 and 3.5–7.0% respectively, of the amount detected in the first flood. The CSFW performs a high buffer capacity for herbicides, capable to provide water purification service, protecting downstream surface water. More- over, mitigation capacity of a CSFW for a heavy runoff from a 10 ha basin is 90% for every 50 m in length of a 15 m wide wetland. This confirms that the implementation of CSFWs in agro-systems can improve the sustainability of agricultural production. Keywords Ecosystem services Á Artificial wetlands Á Water purification Á Metolachlor Á Sustainable agriculture Á Terbuthylazine Guest editors: Pierluigi Viaroli, Marco Bartoli & Jan Vymazal / Wetlands Biodiversity and Processes: Tools for Management and Conservation Electronic supplementary material The online version of this article (doi:10.1007/s10750-015-2375-1) contains supple- mentary material, which is available to authorized users. S. E. Pappalardo (&) Á V. Gasparini Á G. Zanin Á M. Borin Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Agripolis, Viale dell’Universita ` 16, 35020 Legnaro, PD, Italy e-mail: salvatore.pappalardo@unipd.it V. Gasparini e-mail: gasparini.valentina@gmail.com G. Zanin e-mail: giuseppe.zanin@unipd.it M. Borin e-mail: maurizio.borin@unipd.it S. Otto Institute of Agro-environmental and Forest Biology - CNR, Agripolis, Viale dell’Universita ` 16, 35020 Legnaro, PD, Italy e-mail: stefan.otto@ibaf.cnr.it 123 Hydrobiologia DOI 10.1007/s10750-015-2375-1