1,721,049 research outputs found
Modelling nutrient emissions from river systems and loads to the coastal zone: Po River case study, Italy
Full text linkThe nutrient emission model MONERIS (MOdelling Nutrient Emissions into River Systems) is applied to the Po catchment,
a large (>70,000 km2), densely populated, highly agriculturally exploited and industrialized landscape. The catchment is located
in northern Italy. The Po River discharges into the northwestern Adriatic Sea. Model runs cover the period 1991–2000. The
purpose is to model the catchment in 2001, estimating nutrient emissions and natural background in the basin and loads to the
coastal area. The model was calibrated with data for the period 1990–1995. After validation with data for the period 1995–2000,
the model is used to evaluate future catchment management scenarios.
MONERIS is a spatially distributed parameters steady state model with a time scale of 5 years. The emissions considered
are originated from diffuse and point sources and delivered trough various pathways (groundwater, erosion, overland flow,
atmospheric deposition, urban systems and WWTPs). In order to estimate nutrient loads to the river system, MONERIS includes
a retention model.
An overview of model input requirements, data needs and related problems and solutions adopted is presented in the paper.
Simulated and measured data of several sections along the river are compared for calibration and validation. The relative
importance of different nutrient generation pathways are evaluated. Finally, forecasted yearly nutrient loads at the outlet of
PO basin for the years 2001, 2008 and 2016, consequence of different basin management scenarios, are presented. The results
are ready to be supplied to a water quality Coastal Zone Model, allowing us to evaluate significant switches in trophic state
conditions of the coastal ecosystem [see Artioli, Y., Bendoricchio, G., Palmeri, L., this issue. Defining and modelling the coastal
zone affected by the Po River (Italy). Ecol. Model.]
Valutazione della dispersione atmosferica di idrocarburi dal sito contaminato della area ex-IP - La Spezia
No full textRapport
PROTOCOLLO SPERIMENTALE PER MISURE DI TRACCIANTE PER LA STIMA DEI TEMPI DI RESIDENZA NELL'AREA UMIDA DI CA' DI MEZZO
No full textRapporto intern
Defining and modelling the coastal zone affected by the Po river (Italy)
Full text linkOne of the most important sources of pollution in coastal zones (CZ) is certainly that one produced by human activities in
the associated river basin. Understanding the linkage between water quality in CZ and river catchments is important in order to
better assess CZ processes and to evaluate different management options aimed at improving the coastal ecosystem state. CZ
water quality targets as identified by the Water Framework Directive (EC 2000/60) require an accurate study of the effects of
pollutant loads coming from river discharge.
In order to evaluate the impacts of human activities in river catchments on the associated coastal zone, a sound definition
for this geographic area is needed. Many definitions for this area have been proposed in different contexts. The definition is
generally built upon a particular goal, and is henceforth highly variable according to the different purposes. In this paper a
general methodology allowing to discern those areas of the sea that are directly influenced by fluvial discharge is presented. The
methodology is based on the variation pattern of sea water characteristics, and provides a numerical evaluation of this influence.
In particular an analysis based on salinity as tracer, results in a sound definition of this area. The methodology has been applied
on the case study of the Po river. Due to the significant nutrient loads discharged by the river, the CZ associated with Po is
affected by severe eutrophication phenomena that have important consequences on the ecosystem and on the socio-economy of
the area.
In order to study the impacts of nutrients loads carried by the river, a water quality model (WASP6) has been implemented.
The model simulates the seasonal variability of nutrient concentrations, phytoplankton biomass and dissolved oxygen. Using the
CZ model is possible to compare the effects of variations of nutrient loads on the biochemical (short term) and ecological (long
term) quality of the coastal environment. This is accomplished by feeding nutrients loads forecasted for different scenarios by the
catchment model (MONERIS) as forcing functions to the CZ model. This way the effect of the different catchment management
scenarios are propagated to the CZ model, and the trophic conditions of the coastal ecosystem evaluated using TRIX.
This study has been developed in the context of the European project EUROCAT
A water quality model as tool for the evaluation of the limiting nutrient
No full textEutrophication is one of the major environmental problem that affect water bodies in general and especially coastal zones: the high nutrient loads emitted by the different anthropic activities are usually discharged by the river system in these areas.
The identification of the limiting nutrient plays a key role in the study of eutrophication process: this permits to predict algal group that could easily grow in the ecosystem, to focus the management efforts on the most sensitive nutrient...
Usually a very simple method is used to evaluate the limiting nutrient: the N:P ratio is calculated starting from data coming from monitoring program and then compared with the Refield ratio.
The different methodologies for the estimation of the limiting nutrient have been applied on the coastal zone affected by the Po river discharge. This area, defined by means of a statistical analysis of salinity, is part of the Northern Adriatic sea.
It is evident the different methodologies give different results and that the difference is not Trascurabile
VALUTAZIONE DEGLI INTERVENTI DI RIQUALIFICAZIONE DELL'AREA UMIDA DI CASTELNOVO BARIANO (RO)
No full textIl Laboratorio di Analisi dei Sistemi Ambientali (L.A.S.A.) da anni compie sperimentazioni nell’area umida di Castelnovo Bariano (RO). Tale area è stata costruita impegnando fondi della Regione Veneto con finalità di sperimentazione e ricerca sui processi di fitodepurazione, di evoluzione ecologica e sulle problematiche relative alla gestione di un ecosistema di tipo palustre. Nel corso delle precedenti sperimentazioni sono emersi diversi problemi di carattere idraulico che pregiudicano l’efficacia dell’area nell’abbattimento dei nutrienti. Sono state operate delle modifiche nella primavera del 2005, in seguito alle quali sono state effettuate 3 campagne di monitoraggio. Dal confronto con i dati raccolti prima dei lavori, emerge che le infiltrazioni sono diminuite insieme alla richiesta di acqua del sistema. E’ anche aumentato il tempo di residenza dell’acqua e parallelamente si è ottenuta una migliore resa di abbattimento dei nutrienti
Northern Adriatic sea mass-balance model: trophic structure of a highly-fished and eutrophic ecosystem
Full text linkA trophic network static model of the Northern Adriatic sea (Italy, Slovenia, Croatia) was developed in order to assess trophic
structure, anthropogenic impact and ecosystem stress level. The Northern Adriatic sea is a shallow and eutrophic basin which
has been heavily fished for many years. The river Po is the largest river in the region and discharges a remarkable load of
nitrogen and phosphorous into the system. The model, constructed within the EU-sponsored INCOFISH project and using the well
known mass balance software Ecopath, provides a snapshot of biomasses and energy fluxes in the ecosystem during the 1990’s.
Ecosystem structure was analysed by aggregating fluxes in discrete trophic levels sensu Lindemann, using mixed trophic impact
matrix analysis and calculating different indices specifically to evaluate ecosystem maturity sensu Odum. The analysed system is
highly productive, showing strong energy losses through respiration. The network structure is linear, with little recycling. The
trophic structure is characterized by high primary production and the phytoplankton-based cycle has the highest efficiency of
energy transfer within the system. However, trophic fluxes are mainly based on the detritus cycle. The importance of detritus does
not point out the maturity of the system, as a strong detritus uptake may be due to both the input of the Po river and the low depth
of the basin, the latter allowing resuspension and recirculation of dead organic matter. Mixed trophic impact analysis shows that
top predators have a negligible effect on the system. Rather the system appears to be wasp-waist controlled: small pelagic fish
and zooplankton are the main groups affecting the trophic network. Zooplankton has a strong limiting effect on pelagic fish (which
in turn impact the higher trophic levels) by limiting the energy transfer from bacteria and detritus that they feed upon. The
microbial loop is as important as grazing with respect to the magnitude of the fluxes. Phytoplankton has some impact on the
network and, despite its abundance, appears to be a key resource. The frequent eutrophication-caused blooms may be too intense
for phytoplankton, causing population crashes before grazers can exploit this resource. In general, the system appears to be
strongly impacted by human activities and at an immature stage. The strong pelagic primary production due to eutrophication
could provide the energy to sustain the heavily fished higher levels of the trophic web
Screening degli impatti del progetto di stabilimento di produzione vetro float nell'A.I.A. di Adria-Loreo (RO) sulla componente ambientale atmosfera
No full textRapport
RESIDENCE TIMES AND NUTRIENT ABATEMENT EFFICIENCY ESTIMATION IN THE CONSTRUCTED WETLAND OF CA' DI MEZZO
No full text- …
