1,721,208 research outputs found
Climate change and Mediterranean coastal karst aquifers: the case of Salento (southern Italy)
No full textSecond half of the 20th century was characterized by an increase of groundwater discharge. Numerous aquifers are overexploited in the world and in particular in the Mediterranean area. Problems tie to overexploitation, as piezometric decline and increase of seawater intrusion, are amplified in karst coastal aquifers where the whole effect could be a groundwater quality and quantity degradation.
Focusing on Mediterranean countries, most part of coastal aquifers of Spain, France, Portugal, Slovenia, Croatia, Greece, Albania, Turkey, and Italy are karstic and affected, to different degrees, by seawater intrusion due high pumping extraction rates and low recharge. (COST, 2005; Polemio et al., 2010).
Climate change may particularly aggravate these requirements, especially in the Mediterranean areas, due to the combined effects of semiarid condition climate, or reduced recharge and consequent increase of discharge (Cotecchia et al., 2003; Polemio 2005; Polemio et al., 2009).
The general purpose of this paper is to prove the capability of large-scale numerical models in management of groundwater, in particular for achieve forecast scenarios to evaluate the impacts of climate change on groundwater resources of karst coastal aquifer of Salento (Southern Italy).
The computer codes selected for numerical groundwater modelling were MODFLOW and SEAWAT. Three forecast transient scenarios, referred to 2001-2020, 2021-2040 and 2041-2060, were implemented, on the basis of calibrated and validated model, with the aim to predicting the evolution of piezometric level and seawater intrusion. The scenarios were discussed considering the effects of climate change, sea level rise and change of sea salinity.PublishedViterbo, Italy6A. Monitoraggio ambientale, sicurezza e territorioope
Il rischio idrogeologico in Italia e il ruolo della ricerca scientifica
No full textIn Italia, le frane e le inondazioni sono fenomeni diffusi, ricorrenti e pericolosi. Fra il 1960 e il 2011 ci sono stati almeno 789 eventi di frana che hanno prodotto oltre 5000 vittime (di cui 3417 morti e 15 dispersi) in 522 comuni (6,4% del totale). Nello stesso periodo si sono verificati almeno 505 eventi d’inondazione che hanno prodotto più di 1700 vittime (di 753 morti e 68 dispersi), in 372 comuni (4,6% del totale). Fra il 2005 e il 2011, si sono avuti 82 eventi di frana che hanno prodotto oltre 480 vittime (101 morti, 6 dispersi, 374 feriti) in 70 comuni, e 39 inondazioni in altrettanti comuni con 89 vittime (59 morti, 1 disperso, 29 feriti). Nel periodo 2005-2011 tutte le Regioni hanno sofferto almeno un evento di frana o d’inondazione con vittime, a conferma della diffusione geografica del rischio geo-idrologico. Le cifre dimostrano inequivocabilmente come l’impatto che gli eventi geo-idrologici hanno sulla popolazione sia un problema prioritariamente di rilevanza sociale che enfatizza la rilevanza delle attività scientifiche che possano conseguire risultati utili a ridurre gli effetti negativi.Published74.4. Scenari e mitigazione del rischio ambientaleN/A or not JCRope
Climate change and Mediterranean coastal karst aquifers: the case of Salento (southern Italy)
No full textSecond half of the 20th century was characterized by an increase of groundwater discharge. Numerous aquifers are overexploited in the world and in particular in the Mediterranean area. Problems tie to overexploitation, as piezometric decline and increase of seawater intrusion, are amplified in karst coastal aquifers where the whole effect could be a groundwater quality and quantity degradation.
Focusing on Mediterranean countries, most part of coastal aquifers of Spain, France, Portugal, Slovenia, Croatia, Greece, Albania, Turkey, and Italy are karstic and affected, to different degrees, by seawater intrusion due high pumping extraction rates and low recharge. (COST, 2005; Polemio et al., 2010).
Climate change may particularly aggravate these requirements, especially in the Mediterranean areas, due to the combined effects of semiarid condition climate, or reduced recharge and consequent increase of discharge (Cotecchia et al., 2003; Polemio 2005; Polemio et al., 2009).
The general purpose of this paper is to prove the capability of large-scale numerical models in management of groundwater, in particular for achieve forecast scenarios to evaluate the impacts of climate change on groundwater resources of karst coastal aquifer of Salento (Southern Italy).
The computer codes selected for numerical groundwater modelling were MODFLOW and SEAWAT. Three forecast transient scenarios, referred to 2001-2020, 2021-2040 and 2041-2060, were implemented, on the basis of calibrated and validated model, with the aim to predicting the evolution of piezometric level and seawater intrusion. The scenarios were discussed considering the effects of climate change, sea level rise and change of sea salinity.PublishedViterbo, Italy6A. Monitoraggio ambientale, sicurezza e territorioope
Apulian piezometric time series: regime and climatic and human effects
No full textThis work is based on data acquisition and analysis of chronology sequences of piezometric, rainfall and thermometric data of Apulian aquifers. Methods of time series analysis are used. This approach has allowed characterising the piezometric regime and trend related to the natural recharge variation.Published153-162N/A or not JCRope
Apulian piezometric time series: regime and climatic and human effects
No full textThis work is based on data acquisition and analysis of chronology sequences of piezometric, rainfall and thermometric data of Apulian aquifers. Methods of time series analysis are used. This approach has allowed characterising the piezometric regime and trend related to the natural recharge variation.Published153-162N/A or not JCRope
Devolopment of human activities in the underground space and groundwater protection
No full textThe utilization of the underground space for carrying out human activities goes far back into antiquity. A review of underground space major uses over time is given and pros and cons relating to the huge increase in tunnelling are listed. The impact on groundwater resources is estimated. And significant variations in the aquifer regulation and storage capacity volume, hydraulic conductivity and transmissivity, water flow and energy velocity are discussed.PublishedCernobbioope
Geohydrological disasters and transportation network in a region with complex hydrogeomorphological characteristics (Calabria, Southern Italy)
No full textIl complesso assetto geomorfologico della Calabria e le sue peculiarità climatiche, tra cui una piovosità maggiore della media nazionale, fanno si che questa sia una delle regioni maggiormente esposte a fenomenologie di dissesto idrogeologico. Quale effetto indiretto della rude morfologia regionale e dello sviluppo territoriale oblungo, il reticolo stradale principale ha un basso grado di interconnessione, circostanza questa che ne amplifica l’intrinseca vulnerabilità. In tale contesto, l’incidenza delle vie di comunicazione veloci e ad elevata capacità è trascurabile, mentre le tipologie costruttive risultano essere, come discusso da questo contributo, non adeguate alla diffusa vulnerabilità idrogeologica del territorio. Piogge intense e/o prolungate determinano la frequente insorgenza di crisi territoriali, comunemente definite eventi alluvionali, che determinano sia frane diffuse che catastrofiche piene, e causano perdite di vite umane nonchè gravi e duraturi danni alle infrastrutture di trasporto. In tali circostanze, i dissesti che si determinano lungo la rete viaria rappresentano una fonte di danno sia diretto che indiretto per la comunità e nei casi più gravi costituiscono un impedimento alle attività di protezione civile. L’analisi sistematica delle tipologie di dissesti che hanno interessato la rete viaria in un arco temporale sufficientemente esteso (80 anni), selezionato per la sua significatività, costituisce uno strumento per la valutazione delle relazioni causa effetto fra il verificarsi di piene ed eventi alluvionali da una parte e l’insorgenza dei dissesti della rete viaria dall’altra. La ricerca si propone di individuare indicazioni utili alla programmazione della manutenzione ordinaria e nonché alla gerarchizzazione delle priorità degli interventi volti a minimizzare i danni causati dalle piene alle infrastrutture lineari di trasporto.PublishedRomaope
Hydrogeological modeling for sustainable groundwater management under climate change effects for a karstic coastal aquifer (Southern Italy)
No full textSeawater intrusion is a pervasive problem affecting coastal aquifer, where the concentration of population and the increasing water demand creates risks of overexploitation, especially in those areas where is the only resource of drinking and irrigation water. This phenomenon is more considerable for the coastal karst aquifers, as observed in many Mediterranean countries and in some Italian regions as Friuli, Sardegna, Sicilia, Lazio, Campania and Puglia. This note aims to describe a research activity finalised to define a numerical model as management tools for groundwater resource of Salento (South Italy) to reduce the quantitative and qualitative degradation risks.
The numerical codes used was MODFLOW (McDonald and Harbaught, 1988) and SEAWAT (Guo and Langevin, 2002). The active domain of the study area (active cells) covered approximately 2,300 km2 with 45,925 cells. Vertically, to allow a good lithological and hydrogeological discretization, the area was divided into 12 layers, from 214 to -350 m asl. Thickness and geometry of layers was defined on the basis of the aquifer conceptualisation based on the 3D knowledge of hydrogeological complexes.
On the basis of detailed geological and hydrogeological conceptualisation, the climate change effects were considered in terms of natural recharge variations from 1930 to 1999 (Cotecchia et al., 2005; Polemio and Casarano, 2008). To take account of anthropogenic activity, mainly due to tourism and agriculture, the discharging trend was assessed, focusing on late decenniums (eighties and nineties), in which the discharge increase was mainly observed. Models representing the natural steady-state condition (using data of thirties) and transient scenarios of late decenniums were realised.
The purpose of this first model implementation was, besides validated model, to assess the groundwater availability and quality in a recent period of seventy years (Polemio and Romanazzi, 2012; Romanazzi and Polemio, 2013).
Results emphasize an essential decrease of piezometric levels and a worsening of seawater intrusion. On these bases, six forecasting transient scenarios were implemented, referred to future periods of about twenty years (2000-2020, 2021-2040 and 2041-2060) with the aim to predicting the evolution of piezometric level and seawater intrusion. For forecast data about precipitation and temperature, among the many models in the literature, we referred to the model developed by Giorgi and Lionello (2008), in relation to the defined scenario A1B. The model predicts temperature variations (°C) and precipitation percentage variation for the period 2001-2100. It was considered an average temperature variation form 0.9 °C (2001-2020) to 2.4 °C (2040-2060). Precipitation shows a negative percentage change (referred to 1960-80) equal to -3.9, -5.9 and -9,0% respectively for 2000-2020, 2021-2040 and 2041-2060. These climatic data are in agreement with other climate change models (Garcia- Ruiz et al., 2011).
For the three future scenarios new recharge and discharge were assessed. In terms of discharge, they are mainly due to irrigation. For this kind of future utilisation two hypotheses were considered. The first assumes that type and extension of cultivations will be steady and, as an effect of climate change, the pressure on groundwater resource will further rise as necessary to satisfy irrigation demand (Dragoni and Sukhjia, 2008; Goderniaux et al., 2008). In the second hypothesis the irrigation discharge will be steady and equal to those of the 1999 due the adaption of cultivation types and irrigation practices. In both cases the scenario results show a general decrease of the piezometric head and a deterioration of water quality caused by seawater intrusion (Romanazzi et al., 2013). The results call for new land and groundwater resources management criteria.
Considering the Water Framework Directive (EC, 2000) and international and regional experiences (LaMoreaux, 2010; Jiménez-Madrid, 2010; Polemio et al., 2009, Polemio et al., 2010), the study area was subdivided in three zones. To define the zone boundary, the threshold criterion was used (Polemio and Limoni, 2001; Polemio et al., 2009). The threshold between pure fresh groundwater and any type of mixing between fresh and saline groundwater was defined equal to of 0.5 g/l. In the first zone, the coastal zone, salinity was always (in the past) above the threshold, a transition zone, where salinity was variable respect to the threshold, and a third zone or inland zone where salinity value was permanently below the threshold.
These three zones were implemented in the model. Different combinations of discharge criterions applied to these zones suggest the best choices to be applied for management criteria able to safely considered the future effects of climate changes.PublishedHusum (Germany)6A. Monitoraggio ambientale, sicurezza e territorioope
Vulnerabilità degli acquiferi dei Monti di Maratea
No full textCarbonate rocks outcrop in the area of Maratea mountains. They belong to the Bulgheria-Verbicaro and Alburno-Cervati Units and exhibit heavy fracturing and occasional karstification. The structural setting depends on the overthrusting of the carbonate rocks of the Bulgheria-Verbicaro Unit on a clayey-marly complex made up of the plastic soils of the Liguride Unit.
The intrinsic vulnerability of the area at large was assessed by means of a parametric point-and-weight system, whereas the SINTACS method was applied on a higher scale to assess a sample area located on the western side, along the valley of Maratea Fiumicello where a number of springs and instability phenomena are reported.
Hence, the area is highly vulnerable. All the more, the urban and suburban area of Maratea because of the high residential development in the vicinity of springs. Severe problems of slope instability have repeatedly damaged the water supply and sewage system, thereby affecting the quality and the quantity of readily available groundwater resources and contributing to the degradation of the built-up area as a result of the impact on slope stability and construction works in place.Published113-1175.5. TTC - Sistema Informativo TerritorialeJCR Journalope
Hydrogeological modeling for sustainable groundwater management under climate change effects for a karstic coastal aquifer (Southern Italy)
No full textSeawater intrusion is a pervasive problem affecting coastal aquifer, where the concentration of population and the increasing water demand creates risks of overexploitation, especially in those areas where is the only resource of drinking and irrigation water. This phenomenon is more considerable for the coastal karst aquifers, as observed in many Mediterranean countries and in some Italian regions as Friuli, Sardegna, Sicilia, Lazio, Campania and Puglia. This note aims to describe a research activity finalised to define a numerical model as management tools for groundwater resource of Salento (South Italy) to reduce the quantitative and qualitative degradation risks.
The numerical codes used was MODFLOW (McDonald and Harbaught, 1988) and SEAWAT (Guo and Langevin, 2002). The active domain of the study area (active cells) covered approximately 2,300 km2 with 45,925 cells. Vertically, to allow a good lithological and hydrogeological discretization, the area was divided into 12 layers, from 214 to -350 m asl. Thickness and geometry of layers was defined on the basis of the aquifer conceptualisation based on the 3D knowledge of hydrogeological complexes.
On the basis of detailed geological and hydrogeological conceptualisation, the climate change effects were considered in terms of natural recharge variations from 1930 to 1999 (Cotecchia et al., 2005; Polemio and Casarano, 2008). To take account of anthropogenic activity, mainly due to tourism and agriculture, the discharging trend was assessed, focusing on late decenniums (eighties and nineties), in which the discharge increase was mainly observed. Models representing the natural steady-state condition (using data of thirties) and transient scenarios of late decenniums were realised.
The purpose of this first model implementation was, besides validated model, to assess the groundwater availability and quality in a recent period of seventy years (Polemio and Romanazzi, 2012; Romanazzi and Polemio, 2013).
Results emphasize an essential decrease of piezometric levels and a worsening of seawater intrusion. On these bases, six forecasting transient scenarios were implemented, referred to future periods of about twenty years (2000-2020, 2021-2040 and 2041-2060) with the aim to predicting the evolution of piezometric level and seawater intrusion. For forecast data about precipitation and temperature, among the many models in the literature, we referred to the model developed by Giorgi and Lionello (2008), in relation to the defined scenario A1B. The model predicts temperature variations (°C) and precipitation percentage variation for the period 2001-2100. It was considered an average temperature variation form 0.9 °C (2001-2020) to 2.4 °C (2040-2060). Precipitation shows a negative percentage change (referred to 1960-80) equal to -3.9, -5.9 and -9,0% respectively for 2000-2020, 2021-2040 and 2041-2060. These climatic data are in agreement with other climate change models (Garcia- Ruiz et al., 2011).
For the three future scenarios new recharge and discharge were assessed. In terms of discharge, they are mainly due to irrigation. For this kind of future utilisation two hypotheses were considered. The first assumes that type and extension of cultivations will be steady and, as an effect of climate change, the pressure on groundwater resource will further rise as necessary to satisfy irrigation demand (Dragoni and Sukhjia, 2008; Goderniaux et al., 2008). In the second hypothesis the irrigation discharge will be steady and equal to those of the 1999 due the adaption of cultivation types and irrigation practices. In both cases the scenario results show a general decrease of the piezometric head and a deterioration of water quality caused by seawater intrusion (Romanazzi et al., 2013). The results call for new land and groundwater resources management criteria.
Considering the Water Framework Directive (EC, 2000) and international and regional experiences (LaMoreaux, 2010; Jiménez-Madrid, 2010; Polemio et al., 2009, Polemio et al., 2010), the study area was subdivided in three zones. To define the zone boundary, the threshold criterion was used (Polemio and Limoni, 2001; Polemio et al., 2009). The threshold between pure fresh groundwater and any type of mixing between fresh and saline groundwater was defined equal to of 0.5 g/l. In the first zone, the coastal zone, salinity was always (in the past) above the threshold, a transition zone, where salinity was variable respect to the threshold, and a third zone or inland zone where salinity value was permanently below the threshold.
These three zones were implemented in the model. Different combinations of discharge criterions applied to these zones suggest the best choices to be applied for management criteria able to safely considered the future effects of climate changes.PublishedHusum (Germany)6A. Monitoraggio ambientale, sicurezza e territorioope
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