Agrosystems and Ecosystem Services: an agroenvironmental assessment of vegetated systems for phytoremediation of water from agricultural drainage

Relationships between Ecosystem Services and agrosystems are extremely important both to understand the bidirectional flow of services from/to agriculture and to quantify goods and benefits for human societies. Wetland systems nowadays represent an important cornerstone for beneficial Ecosystem Services, especially in intensive agricultural landscapes characterized by shallow water and a dense minor channel network like the territory of the Venice Lagoon drainage system. Wetlands provide a crucial suite of regulating, supporting, provisioning and cultural services to regulate water flows and nutrient cycling, remove and detoxify excess fertilizers and pesticides, sequester carbon, enhance biodiversity and provide cultural benefits to local communities. By three experimental study cases this research present results about the assessment of the water purification service provided by wetlands in mitigating agricultural contamination; moreover, estimation of a provisioning service such as bioenergy derived from wetland vegetation was performed. In the study case “a constructed wetland for water purification services from pesticide in an intensive cropping system” results show that the system can reduce runoff concentration of metolachlor and terbuthylazine by a factor of 45-80 even in extreme flooding conditions. Herbicides retention in the constructed wetland 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. In the second experimentation “vegetated ditches as water purification systems to mitigate contamination from pesticides runoff” results show that the ditch can immediately reduce runoff concentration of herbicides by at least 50% even in extreme flooding conditions; as a general rule, a runoff of 1 mm from 5 ha is mitigated by 99% in 100 m of vegetated ditch. In the study case “Assessing phytoremediation performance of an integrated agricultural wetland” results show that median c