Actual and Forecasted Vulnerability Assessment to Seawater Intrusion via GALDIT-SUSI in the Volturno River Mouth (Italy)

Abstract

Coastal areas have become increasingly vulnerable to groundwater salinization, especially in the last century, due to the combined effects of climate change and growing anthropization. In this study, a novel methodology named GALDIT-SUSI was applied in the floodplain of the Volturno River mouth for the current (2018) and future (2050) evaluation of seawater intrusion accounting for the expected subsidence and groundwater salinization rates. Several input variables such as digital surface model, land use classification, subsidence rate and drainage system have been mapped via remote sensing resources. The current assessment highlights how areas affected by salinization coincide with the semiperennial lagoons and inland depressed areas where paleosaline groundwaters are present. The future assessment (2050) shows a marked increase of salinization vulnerability in the coastal strip and in the most depressed areas. The results highlight that the main vulnerability driver is the Revelle index, while predicted subsidence and recharge rates will only slightly affect groundwater salinization. This case study indicates that GALDIT-SUSI is a reliable and easy-to-use tool for the assessment of groundwater salinization in many coastal regions of the world.

Genesis and Distribution of Low Fluvial Terraces Formed by Holocene Climate Pulses in Brazil

“…As depicted in Figure 9a, the geochronological results indicate that depositional events associated with the genesis of low river terraces in coastal compartments are not directly related to the influences exerted by the cooling pulses of the northern hemisphere [15,56], as observed in the geomorphological compartments located in continental areas of the Northeast and Southeast of Brazil (climate dipole). However, the concentration of depositional ages in the Late Holocene-when correlated with isotopic records of the speleothems from the Botuverá (Figure 9b-d) and Cristal (Figure 9e) caves-is also associated with higher-intensity rainfall events along with the Holocene historical series [61,[85][86][87][88][89][90][91]. Such events are possibly intensified by the depositional processes which helped create low terraces in the Late Holocene, characterized by younger depositional ages than the continental samples.…”

The Issue of Land Subsidence in Coastal and Alluvial Plains: A Bibliometric Review

“…The orange cluster includes Australia, Germany, Indonesia, Italy, Netherlands, Russia, and the UK. It is the largest cluster and includes the themes relative to the risks related to subsidence [103], like flooding [104,105], but also to the main causes such as sea level rise [106,107] and climate change. Studies in Canada, China, Iran, Mexico, Taiwan, and Thailand (red cluster) are mainly related to hydrogeology [108][109][110], with a lesser extent to mitigation measures related to the exploitation from the subsoil [83,[111][112][113].…”

The role of the geological model in the analysis of land subsidence: a key lecture from the Volturno River alluvial plain (southern Italy)

“…2a). The transformation of the territory has led to a strong urbanization and to the development of agriculture and animal farming (Vigliotti & Ruberti, 2017); the impact on the river courses leads to a negative sedimentary balance and to an increase in the erosion rates, that coupled with the subsidence phenomenon and the sea level rise, represents a serious hazard, expecially in the coastal zone, as it can lead to an increased vulnerability to flooding and the disappearance of coastal ecosystems (Donadio et al, 2018;Busico et al, 2021).…”