Atmospheric deposition

 

Studies on atmospheric deposition chemistry started at the CNR of Verbania in 1975 with the installation of a sampler at Pallanza, in the garden of the Institute.

 

This research includes running deposition sampling stations, the subsequent analysis of the samples, updating sampling equipment and perfecting analytical techniques and quality control, and finally elaborating the data collected to evaluate the effects of the depositions on ecosystems.

The CNR-ISE has taken part in several Italian and international research projects on atmospheric deposition. Among these, the Institute coordinated, on behalf of the Ministry of the Environment, the Italian Network for the Study of Wet Deposition (RIDEP) from 1988 to 1992, and has represented Italy in the Task Force of the International Cooperative Programme for the evaluation and monitoring of the effects of acidification on rivers and lakes (ICP Waters) since 1995.

Finally, since 1997 the CNR has been responsible for the sampling and analysis of atmospheric deposition in permanent forest areas of the CONECOFOR programme.

Currently the chemical laboratory of the CNR of Verbania is analysing atmospheric deposition collected:

  • At 7 sampling stations located in the Italian part of the Lake Maggiore watershed along a latitudinal and altitudinal gradient (from around 200 to 1600m a.s.l.). Long term data exist for these stations (since 1975 for Pallanza, since the 80s or the 90s for the others). Major aims of this research are the evaluation of trends (time variations in deposition chemistry) in response to the decrease of emissions into the atmosphere of S and N compounds and the quantification of atmospheric loads of acidifying compounds, nutrients, and, recently, heavy metals on the aquatic ecosystems in the area of the Lake Maggiore watershed (watercourses and subalpine and alpine lakes). Heavy metals input by atmospheric deposition are studied at three different sampling sites in Lake Maggiore watershed, representative of varying proximity to emission sources. Results showed rather low levels of heavy metals in atmospheric deposition. Measured deposition of lead and cadmium in particular, whose emission level are strictly under the control of the EU legislation, are in agreement with those calculated within international monitoring Programmes (e.g. EMEP Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe).In 20 of the 22 forest areas of the FutMon, some already included in the CONECOFOR, network, representative of the main types of Italian forest. Open field, throughfall and stemflow deposition is collected, and comparison of these values provides indications on the ion loads actually reaching the soil and the ion exchange phenomena which occur primarily at the leaf surface. Analyses are performed to study atmospheric deposition chemistry, over a sufficiently extensive network, to stimulate knowledge of the phenomenon of deposition of pollutants and nutrients on a nation-wide scale, and to establish what effect it has on the general state of forest ecosystems.
  • In 8 areas from 2017 LIFE SMART4action project, part of the 22 forest areas of the FutMon, some already included in the CONECOFOR network, representative of the main types of Italian forest. Open field, throughfall and stemflow deposition is collected, and comparison of these values provides indications on the ion loads actually reaching the soil and the ion exchange phenomena which occur primarily at the leaf surface. Analyses are performed to study atmospheric deposition chemistry, over a sufficiently extensive network, to stimulate knowledge of the phenomenon of deposition of pollutants and nutrients on a nation-wide scale, and to establish what effect it has on the general state of forest ecosystems.

For a more detailed description see:

On the tracks of Nitrogen deposition effects on temperate forests at their southern European range - an observational study from Italy (2014)

Report on time trends and spatial patterns of ecosystem chemistry (2016)