Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | SPATIAL EVALUATION OF THE RISK OF GROUNDWATER QUALITY DEGRADATION. A COMPARISON BETWEEN DISJUNCTIVE KRIGING AND GEOSTATISTICAL SIMULATION |
| Abstract | In some previous papers a probabilistic methodology was introduced to estimate a spatial index of risk of groundwater quality degradation, defined as the conditional probability of exceeding assigned thresholds of concentration of a generic chemical sampled in the studied water system. A crucial stage of this methodology was the use of geostatistical techniques to provide an estimation of the above-mentioned probability in a number of selected points by crossing spatial and temporal information. In this work, spatial risk values were obtained using alternatively stochastic conditional simulation and disjunctive kriging. A comparison between the resulting two sets of spatial risks, based on global and local statistical tests, showed that they do not come from the same statistical population and, consequently, they cannot be viewed as equivalent in a statistical sense. At a first glance, geostatistical conditional simulation may appear to represent the spatial variability of the phenomenon more effectively, as the latter tends to be smoothed by DK. However, a close examination of real case study results suggests that disjunctive kriging is more effective than simulation in estimating the spatial risk of groundwater quality degradation. In the study case, the potentially 'harmful event' considered, threatening a natural 'vulnerable groundwater system,' is fertilizer and manure application. |
| Source | Environmental monitoring and assessment (Print) 137 (1-3), pp. 261–273 |
| Keywords | GroundwaterDisjunctive krigingGeostatistical simulationRisk assessment |
| Journal | Environmental monitoring and assessment (Print) |
| Editor | Kluwer Academic Publishers, London, Paesi Bassi |
| Year | 2008 |
| Type | Articolo in rivista |
| DOI | 10.1007/s10661-007-9758-3 |
| Authors | BARCA E.; PASSARELLA G. |
| Text | 42265 2008 10.1007/s10661 007 9758 3 ISI Web of Science WOS 000252295500023 Scopus 2 s2.0 38349061855 PubMed 17564802 Groundwater Disjunctive kriging Geostatistical simulation Risk assessment SPATIAL EVALUATION OF THE RISK OF GROUNDWATER QUALITY DEGRADATION. A COMPARISON BETWEEN DISJUNCTIVE KRIGING AND GEOSTATISTICAL SIMULATION BARCA E.; PASSARELLA G. E. Barca and G. Passarella Water Research Institute, IRSA CNR, National Research Council, via F. De Blasio, 5, 70132 Bari, Italy In some previous papers a probabilistic methodology was introduced to estimate a spatial index of risk of groundwater quality degradation, defined as the conditional probability of exceeding assigned thresholds of concentration of a generic chemical sampled in the studied water system. A crucial stage of this methodology was the use of geostatistical techniques to provide an estimation of the above mentioned probability in a number of selected points by crossing spatial and temporal information. In this work, spatial risk values were obtained using alternatively stochastic conditional simulation and disjunctive kriging. A comparison between the resulting two sets of spatial risks, based on global and local statistical tests, showed that they do not come from the same statistical population and, consequently, they cannot be viewed as equivalent in a statistical sense. At a first glance, geostatistical conditional simulation may appear to represent the spatial variability of the phenomenon more effectively, as the latter tends to be smoothed by DK. However, a close examination of real case study results suggests that disjunctive kriging is more effective than simulation in estimating the spatial risk of groundwater quality degradation. In the study case, the potentially harmful event considered, threatening a natural vulnerable groundwater system, is fertilizer and manure application. 137 http //link.springer.com/article/10.1007/s10661 007 9758 3 Articolo su rivista internazionale con IF Received 19 July 2006 / Revised 24 March 2007 / Accepted 6 April 2007 / Published online 13 June 2007 author for correspondence, e mail emanuele.barca@ba.irsa.cnr.it SPATIAL EVALUATION OF THE RISK OF GROUNDWATER QUALITY DEGRADATION. A COMPARISON BETWEEN DISJUNCTIVE KRIGING AND ... Articolo su rivista internazionale con IF Received 19 July 2006 / Revised 24 March 2007 / Accepted 6 April 2007 / Published online 13 June 2007 author for correspondence, e mail emanuele.barca@ba.irsa.cnr.it INT_J_11.pdf Articolo in rivista Kluwer Academic Publishers 0167 6369 Environmental monitoring and assessment Print Environmental monitoring and assessment Print Environ. monit. assess. Print Environmental monitoring and assessment. Print emanuele.barca BARCA EMANUELE giuseppe.passarella PASSARELLA GIUSEPPE TA.P04.005.008 Integrazione di metodologie per il monitoraggio e la modellizzazione per la gestione delle risorse idriche |