Soil Budget, Net Export, and Potential Sinks of Nitrogen in the Lower Oglio River Watershed (Northern Italy)

Soana, Elisa; Racchetti, Erica; Laini, Alex; Bartoli, Marco; Viaroli, Pierluigi

doi:10.1002/clen.201000454

Cited by 39 publications

(47 citation statements)

References 66 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…it/dati.htm; Agricultural Information System of Lombardy Region, 2008; www.siarl.regione.lombardia.it), then aggregated to the catchment scale by means of GIS techniques. The overall budget gains robustness from the comprehensive and high-resolution datasets available for this area and the use of site-specific agronomic coefficients (for more details see Soana et al, 2011). Uncertainties derive from those rates (i.e.…”

Section: The Nitrate "Anomaly" In the Oglio Rivermentioning

confidence: 99%

“…The calculation was performed by multiplying monthly dissolved and particulate nitrogen concentrations (NH Calculated total nitrogen export from the watershed approached 13 000 t N yr −1 , with 90 % as nitrate. Comparing population (333 inhabitants km −2 ) and N export (2950 kg N-NO − 3 km −2 ) per unit area relative to other impacted watersheds in the world, the Oglio had among the highest of both population density and N export (Caraco and Cole, 1999;Billen et al, 2011;Soana et al, 2011).…”

Section: Export Of N From the Basinmentioning

confidence: 99%

“…We thus estimated the range of theoretical denitrification rates in this aquatic compartment according to the equation proposed by Christensen et al (1990) (for more details see Soana et al, 2011). In particular, in order to quantify the maximum potential N removal via denitrification, we up-scaled the calculated upper rates to the whole surface occupied by the ditch network.…”

Section: Nitrogen Removal In the Oglio River And In The Secondary Dramentioning

confidence: 99%

“…This increased N loading has a suite of negative consequences, including demonstrated health effects, enhanced eutrophication, and contributions to global warming (Ward et al, 2005;Davidson, 2009). Open questions about the fate of the nitrogen surplus in impacted watersheds concern where and for how long does the excess nitrogen accumulate, and what processes and transformations does it undergo (van Breemen et al, 2002;Puckett et al, 2011).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Nitrogen balance and fate in a heavily impacted watershed (Oglio River, Northern Italy): in quest of the missing sources and sinks

et al. 2012

View full text Add to dashboard Cite

Abstract. We present data from a comprehensive investigation carried out from 2007 to 2010, focussing on nitrogen pollution in the Oglio River basin (3800 km 2 , Po Plain, Northern Italy). Nitrogen mass balances, computed for the whole basin with 2000 and 2008 data, suggest a large N surplus in this area, over 40 000 t N yr −1 , and increasing between 2000 and 2008. Calculations indicate a very large impact of animal husbandry and agricultural activities in this watershed, with livestock manure and synthetic fertilizers contributing 85 % of total N inputs (about 100 000 t N yr −1 ) and largely exceeding crop uptake and other N losses (about 60 000 t N yr −1 ). Nitrogen from domestic and industrial origin is estimated as about 5800 and 7200 t N yr −1 , respectively, although these loads are overestimated, as denitrification in treatment plants is not considered; nonetheless, they represent a minor term of the N budget. Annual export of nitrogen from the basin, calculated from flow data and water chemistry at the mouth of the Oglio River, is estimated at 13 000 t N yr −1 , and represents a relatively small fraction of N inputs and surplus (∼12 % and 34 %, respectively). After considering N sinks in crop uptake, soil denitrification and volatilization, a large excess remains unaccounted (∼26 000 t N yr −1 ) in unknown temporary or permanent N sinks. Nitrogen removal via denitrification was evaluated in the Oglio riverbed with stable isotope techniques (δ 15 N and δ 18 O in nitrate). The downstream final segment of the river displays an enriched nitrate stable isotope composition but calculations suggest a N removal corresponding to at most 20 % of the unaccounted for N amount. Denitrification was also evaluated in riverine wetlands with the isotope pairing technique. Areal rates are elevated but overall N removal is low (about 1 % of the missing N amount), due to small wetland surfaces and limited lateral connectivity. The secondary drainage channel network has a much higher potential for nitrogen removal via denitrification, due to its great linear development, estimated in over 12 500 km, and its capillary distribution in the watershed. In particular, we estimated a maximum N loss up to 8500 t N yr −1 , which represents up to 33 % of the unaccounted for N amount in the basin. Overall, denitrification in surface aquatic habitats within this basin can be responsible for the permanent removal of about 12 000 t N yr −1 ; but the fate of some 14 000 t remains unknown. Available data on nitrate concentration in wells suggest that in the central part of the watershed groundwater accumulates nitrogen. Simultaneously, we provide evidences that part of the stored nitrate can be substantially recycled via springs and can pollute surface waters via rivergroundwater interactions. This probably explains the ten fold increase of nitrate concentration in a reach of the Oglio River where no point pollutions sources are present.

show abstract

Section: The Nitrate "Anomaly" In the Oglio Rivermentioning

confidence: 99%

Section: Export Of N From the Basinmentioning

confidence: 99%

Section: Nitrogen Removal In the Oglio River And In The Secondary Dramentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Nitrogen balance and fate in a heavily impacted watershed (Oglio River, Northern Italy): in quest of the missing sources and sinks

et al. 2012

View full text Add to dashboard Cite

show abstract

“…This is probably due to both the characteristics of the sites, the production management methods and the fertilizers efficiency. Addressing open research questions about the pathway of the nitrogen input and output implies needs to answer where and for how long does the excess nitrogen accumulate (Soana et al, 2011;Bartoli et al, 2012). The interrelationships between these questions are manifold and encompass the processes and the transformation that nitrogen undergoes in the environment across the soil-water-atmosphere system.…”

Section: Introductionmentioning

confidence: 99%

Spatialised agricultural nitrogen balance of Veneto region, Northern Italy: sources identification, assessment and policy relevance

2014

Global NEST Journal

View full text Add to dashboard Cite

The aim of this study is to deepening knowledge on the agricultural nitrogen cycle within the Veneto region (Northern Italy) by computing the Gross Nitrogen Balance (GNB) with highly geographical resolution. Spatialised maps of nitrogen input and output, created using the most detailed information available, are important tools for assessing environmental sustainability. ). The GIS-based analysis highlights interdependencies between farmer's choices of land uses and the environmental pressures of agricultural activities at the sub-regional level. The results of the study can be used to inform policy makers about the effects caused by environmental management actions that should take into account the interlinkages between landscapes, habitats, biodiversity and ecological integrity.

show abstract

The importance of being natural in a human‐altered riverscape: role of wetland type in supporting habitat heterogeneity and the functional diversity of vegetation

Bolpagni

Piotti

2015

Aquatic Conservation

View full text Add to dashboard Cite

1. Human activities have dramatically affected the status of river ecosystems, mainly by completely altering their natural dynamics. One of the main questions in this regard is: 'How do the origin (natural or artificial) and hydrology (lentic or lotic) of a riverine wetland influence its heterogeneity and the functional diversity of its vegetation?'2. To answer this question, data from 60 wetlands were collected along the Oglio River (northern Italy), ã 700 km 2 ecosystem that is a typically over-exploited plain. In order to perform a quantitative assessment of habitat heterogeneity and vegetation diversity, a hierarchical approach was applied to sample sites divided into four functional zones (FZs) according to distinct seasonal inundation patterns (persistently aquatic, riparian, seasonally emergent and lateral zones).3. Plant communities were randomly surveyed in each FZ by using five replicates of 4 m 2 plots for aquatic and herbaceous plant communities and five replicates of 64 m 2 plots for woody and shrub communities. Data on species cover were estimated by standard methods (geometric-centered scale) 4. The highest values of heterogeneity (FZs per site) and vegetation diversity (plant communities per site) were found in natural lentic sites, whereas natural lotic sites exhibited the lowest values. A clear dependence of plant community assets on wetland origin was detected, thereby confirming the close relationship between heterogeneity and vegetation diversity. 5. Present results highlight the fundamental role played by natural sites in maintaining aquatic and wetland vegetation diversity in human-altered riverscapes. The pivotal role of water level fluctuations in promoting the diversity and distribution of aquatic and hygrophilous vegetation also clearly emerges.

show abstract

Soil Budget, Net Export, and Potential Sinks of Nitrogen in the Lower Oglio River Watershed (Northern Italy)

Cited by 39 publications

References 66 publications

Nitrogen balance and fate in a heavily impacted watershed (Oglio River, Northern Italy): in quest of the missing sources and sinks

Nitrogen balance and fate in a heavily impacted watershed (Oglio River, Northern Italy): in quest of the missing sources and sinks

Spatialised agricultural nitrogen balance of Veneto region, Northern Italy: sources identification, assessment and policy relevance

The importance of being natural in a human‐altered riverscape: role of wetland type in supporting habitat heterogeneity and the functional diversity of vegetation

Contact Info

Product

Resources

About