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For effective lakes’ management, high-frequent water quality data on a synoptic scale are essential. The aim of this study is to test the suitability of the latest generation of satellite sensors to provide information on lake water quality parameters for the five largest Italian subalpine lakes. In situ data of phytoplankton composition, chlorophyll-a (chl-a) concentration and water reflectance were used in synergy with satellite observations to map some algal blooms in 2016. Chl-a concentration maps were derived from satellite data by applying a bio-optical model to satellite data, previously corrected for atmospheric effects. Results were compared with in situ data, showing good agreement. The shape and magnitude of water reflectance from different satellite data were consistent. Output chl-a concentration maps, show the distribution within each lake during blooming events, suggesting a synoptic view is required for these events monitoring. Maps show the dynamic of bloom events with concentration increasing from 2 up to 7 mg m−3 and dropping again to initial value in less than 20 days. Latest generation sensors were shown to be valuable tools for lakes monitoring, thanks to frequent, free of charge data availability over long time periods.

In this study we evaluate the capabilities of three satellite sensors for assessing water composition and bottom depth in Lake Garda, Italy. A consistent physics-based processing chain was applied to Moderate Resolution Imaging Spectroradiometer (MODIS), Landsat-8 Operational Land Imager (OLI) and RapidEye. Images gathered on 10 June 2014 were corrected for the atmospheric effects with the 6SV code. The computed remote sensing reflectance (Rrs) from MODIS and OLI were converted into water quality parameters by adopting a spectral inversion procedure based on a bio-optical model calibrated with optical properties of the lake. The same spectral inversion procedure was applied to RapidEye and to OLI data to map bottom depth. In situ measurements of Rrs and of concentrations of water quality parameters collected in five locations were used to evaluate the models. The bottom depth maps from OLI and RapidEye showed similar gradients up to 7 m (r = 0.72). The results indicate that: (1) the spatial and radiometric resolutions of OLI enabled mapping water constituents and bottom properties, (2) MODIS was appropriate for assessing water quality in the pelagic areas at a coarser spatial resolution, and (3) RapidEye had the capability to retrieve bottom depth at high spatial resolution. Future work should evaluate the performance of the three sensors in different bio-optical conditions.

Total suspended solids (TSS) play a fundamental role in inland waters as different materials including contaminants and pollutants can aggregate to these solids and brought in suspension. This can alter the state of the aquatic ecosystem and the use of freshwater resources. For instance, excessive suspended sediment might condition primary productivity and can hinder water use in agriculture. Suspended solids are one of the most successful parameters that can be measured by means of remote sensing due to the effect of TSS on backscattering and water leaving radiance. Consequently, a variety of applications have been developed since the eighties; they have generally been build on empirical or semi-empirical methods which use reflectance at appropriate wavebands as correlates, or semi-analytical and quasi-analytical approaches such as the spectral inversion procedures which relies on the matching of spectral data to bio-optical forward models. Forward bio-optical modeling is used to show the response of water leaving reflectance depending on inherent optical properties of particles and TSS concentrations. Then, remotely sensed data acquired by different optical sensors are presented to show the performance of state-of-art algorithms for mapping TSS and turbidity in different aquatic systems located in Northern Italy, which include deep clear lakes, a system of fluvial lakes characterized by highly productive waters and a segment of the longest Italian river prior reaching the delta. Overall, the conclusions presented in this chapter encourage the use of remote sensing technology to improve inland water management, although new research efforts remain open to adapt bio-optical modeling to TSS to the variety of sensors used in inland water applications.

The capabilities of different Earth Observation multispectral satellites are employed for detecting and tracking of desert dust coming from North Africa toward the Northern Italy area and for evaluating the impact of Saharan dust deposition in inland waters, such as those of Lake Garda. Absorbing and scattering spectral optical properties of desert aerosol in the atmospheric windows in the ultraviolet, visible-near-infrared, and infrared spectral ranges are exploited in the dust retrieval performed by OMI/Aura, MODIS/Terra-Aqua, and SEVIRI/MSG satellite sensors. Therefore, the direct link between dust deposition and increase in phytoplankton abundance has been assessed retrieving MERIS-based chlorophyll-a (chl-a) concentration for the desert dust events. Estimates of the increased chl-a in the lake have been derived with values in concentration from 30% to 170%. AERONET sun-photometer measurements, gravimetric particulate matter samplings

We provide a short overview on selected aspects of the neuropsychology of patients with temporal lobe epilepsy candidate to surgery. The possible impairment of verbal and non verbal memory is treated in particular. We also present the neuropsychological test battery that we use for the cognitive assessment of such patients before surgery and in the follow-up phase.