A review of hydrological and chemical stressors in the Adige catchment and its ecological status

Abstract

Quantifying the effects of multiple stressors on Alpine freshwater ecosystems is challenging, due to the lack of tailored field campaigns for the contemporaneous measurement of hydrological, chemical and ecological parameters. Conducting exhaustive field campaigns is costly and hence most of the activities so far have been performed addressing specific environmental issues. An accurate analysis of existing information is therefore useful and necessary, to identify stressors that may act in synergy and to design new field campaigns. We present an extended review of available studies and datasets concerning the hydrological, chemical and ecological status of the Adige, which is the second longest river and the third largest river basin in Italy. The most relevant stressors are discussed in the light of the information extracted from a large number of studies. The detailed analysis of these studies identified that hydrological alterations caused by hydropower production are the main source of stress for the freshwater ecosystems in the Adige catchment. However, concurrent effects with other stressors, such as the release of pollutants from waste water treatment plants or from agricultural and industrial activities, have not been explored at depth, so far. A wealth of available studies address a single stressor separately without exploring their concurrent effect. It is concluded that a combination of extended experimental field campaigns, focusing on the coupled effects of multiple stressors, and modeling activities is highly needed in order to quantify the impact of the multifaceted human pressures on freshwater ecosystems in the Adige river.

Evaluation of Gridded Precipitation Data Products for Hydrological Applications in Complex Topography

“…The area is characterized by strong elevation differences ranging from sea level to 3865 m, as presented in Figure 1. The hydrology is characterized by snow and glacier melting in the spring months, and intense precipitation events in summer [36]. Discharge is used for irrigation of intensive agriculture -mainly fruit trees -and through various touristic activities.…”

“…The area is characterized by a humid climate with annual mean precipitation ranging from 500 mm in the inner-Alpine dry areas, such as the Venosta valley [14,35], to 1600 mm. Precipitation distribution shows a pronounced summer peak and relatively dry winters [36]. An overview of the observed mean annual precipitation at the available stations is presented in Figure 2.…”

A parsimonious transport model of emerging contaminants at the river network scale

“…30,000 persons served by the WWTP at Passo del Tonale in August 2015 against 70,000 in February of the same year) and to the streamflow contribution from summer melting of Presanella and Presena glaciers which maintains high streamflow also after the end of snowmelting season (see e.g., Chiogna et al, 2016). The simulated concentrations are higher in winter than in summer also at the control section of Bolzano.…”

Progress with monitoring and assessment in the WFD implementation in five European river basins: significant differences but similar problems

“…One of which includes the implications of climate change in water management. As an example, there are issues identified with regards to the effect of climate change associated with the release of chemical pollutants from snow and glacier melting, an occurrence that has not yet been fully investigated in the case of the Adige basin (Chiogna et al 2016). Similarly, the Ebro RBMPs states that, in the absence of evaluations of the climate scenario prepared by the Ministry of the Environment, a rigid percentage (5%) in the global reduction of natural contributions must be applied, but this plan ignores current research findings for which that reduction for 2050 is expected to be in the range 15%-35% (Bielsa and Cazcarro 2015).…”