Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Climate control on short- and long-term variations of sulphate and nitrate concentrations in alpine streams of Northern Italy along a N saturation gradient |
| Abstract | The role of meteorology, hydrology and atmospheric deposition on the temporal pattern of SO4 and NO3 concentrations was investigated for three streams draining alpine catchments in Northern Italy. The study sites lie on a gradient of atmospheric fluxes of SO4 and NO3 (from about 50 to 80 meqm-2 y-1, and from 40 to 90 meqm-2 y-1, respectively). As a consequence of the increasing N input, the three catchments are also representative of aggrading levels of N saturation. Different methods of statistical analysis were applied to monthly data for the period 1997-2005 to identify which variables (temperature, precipitation, hydrology, SO4 and NO3 deposition) were the main predictors of water chemistry and its change in time. Hydrological changes and snow cover proved to be the main confounding factors in the response to atmospheric deposition in the River Masino catchment. Its particular characteristics (small catchment area, rapid flushing during runoff and thin soil cover) meant that this site responded without a significant delay to SO4 deposition decrease. It also showed a clear seasonal pattern of NO3 concentration, in response to hydrology and biological uptake in the growing season. The selected driving variables failed to model the water chemistry at the other study sites. Nevertheless, temperature, especially extreme values, turned out to be important in both SO4 and NO3 export from the catchments. This result might be largely explained by the effect of warm periods on temperature-dependent processes such as mineralization, nitrification and S desorption. Our findings suggest that surface waters in the alpine area will be extremely sensitive to a climate warming scenario: higher temperatures and increasing frequency of drought could exacerbate the effects of high chronic N deposition. |
| Source | Hydrology and earth system sciences 12 (2), pp. 371–381 |
| Keywords | SURFACE WATERSATMOSPHERIC DEPOSITIONFORESTED CATCHMENTALPS |
| Journal | Hydrology and earth system sciences |
| Editor | Copernicus Publ., Göttingen, Germania |
| Year | 2008 |
| Type | Articolo in rivista |
| DOI | 10.5194/hessd-4-2997-2007 |
| Authors | Rogora M.(1); Arese C.(2); Balestrini R.(2); Marchetto A.(1) |
| Text | 53034 2008 10.5194/hessd 4 2997 2007 ISI Web of Science WOS 000256968000005 SURFACE WATERS ATMOSPHERIC DEPOSITION FORESTED CATCHMENT ALPS Climate control on short and long term variations of sulphate and nitrate concentrations in alpine streams of Northern Italy along a N saturation gradient Rogora M. 1 ; Arese C. 2 ; Balestrini R. 2 ; Marchetto A. 1 1 CNR Institute of Ecosystem Study, 28922 Verbania Pallanza, Italy 2 CNR Water Research Institute, Department of Hydrobiology Applied to Water Pollution, 20047 Brugherio, Milan, Italy The role of meteorology, hydrology and atmospheric deposition on the temporal pattern of SO4 and NO3 concentrations was investigated for three streams draining alpine catchments in Northern Italy. The study sites lie on a gradient of atmospheric fluxes of SO4 and NO3 from about 50 to 80 meqm 2 y 1, and from 40 to 90 meqm 2 y 1, respectively . As a consequence of the increasing N input, the three catchments are also representative of aggrading levels of N saturation. Different methods of statistical analysis were applied to monthly data for the period 1997 2005 to identify which variables temperature, precipitation, hydrology, SO4 and NO3 deposition were the main predictors of water chemistry and its change in time. Hydrological changes and snow cover proved to be the main confounding factors in the response to atmospheric deposition in the River Masino catchment. Its particular characteristics small catchment area, rapid flushing during runoff and thin soil cover meant that this site responded without a significant delay to SO4 deposition decrease. It also showed a clear seasonal pattern of NO3 concentration, in response to hydrology and biological uptake in the growing season. The selected driving variables failed to model the water chemistry at the other study sites. Nevertheless, temperature, especially extreme values, turned out to be important in both SO4 and NO3 export from the catchments. This result might be largely explained by the effect of warm periods on temperature dependent processes such as mineralization, nitrification and S desorption. Our findings suggest that surface waters in the alpine area will be extremely sensitive to a climate warming scenario higher temperatures and increasing frequency of drought could exacerbate the effects of high chronic N deposition. 12 Published version Articolo pubblicato 12_HESS_2008.pdf Articolo in rivista Copernicus Publ. 1027 5606 Hydrology and earth system sciences Hydrology and earth system sciences Hydrol. earth syst. sci. Hydrology and earth system sciences. HESS Gottingen. Print Hydrology and earth system sciences Print ARESE CRISTINA raffaella.balestrini BALESTRINI RAFFAELLA aldo.marchetto MARCHETTO ALDO michela.rogora ROGORA MICHELA TA.P02.014.002 Impatto dei cambiamenti globali sugli ecosistemi acquatici |