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The annual cycle of pelagic primary production (PP) from ocean colour is analysed in a transition area between Ligurian and Tyrrhenian waters, where a general oligo-mesotrophic status is seasonally modified by anthropic impact near the Tuscany coast. Based on the common ecological features six different zones were delimited. Remote sensing data from different satellites (Meteosat, Aqua) were used as input in a primary production model. The daily production of the entire area was computed on pixel by pixel basis (4x4 km) using a modified GIS software. Overwhelming importance of oceanic bloom and high spatial variance of PP (90 ±54 gC m -2 y r -1 ) show that remote sensed data can allow a better

Este artigo apresenta as cinco primeiras medidas do pacote anti-corrupção e comentários a elas pertinentes, expondo o confronto, de membros do Ministério Público e advogados criminalistas. A corrupção na política brasileira suscitou manifestações públicas, asseverando a inconformidade da população, com ênfase nos prejuízos causados ao patrimônio público. Tal entrave tem sido enfrentado pelo Ministério Público Federal que, para tanto, apresentou como instrumento jurídico um conjunto de recomendações denominadas Dez Medidas Contra a Corrupção, o qual inaugura polêmica nacional. O documento acarreta comentários críticos em relação à sua constitucionalidade.

The application of global algorithms to optical satellite imagery often fails to correctly assess the concentrations of seawater constituents (chlorophyll, CHL, suspended sediments, SS, and yellow substance, YS) in spectrally complex marine environments. Additional problems may come from inaccurate radiometric, atmospheric, and geometric corrections of the remotely sensed imagery. This issue is currently analyzed using a data set of seawater samples and MODIS images taken in the Tuscany Sea (Central Italy). The analysis demonstrates that the mentioned problems mainly introduce amplitude variations in the measured reflectance. This may have negative effects on the outcome of inversion algorithms based on the minimization of conventional spectral errors. Such effects can be notably reduced by using an error index derived from the angle between measured and simulated reflectance vectors, which is insensitive to spectral amplitude variations. The potential of a classical and the new error indices is first evaluated by regressing their values against concentration differences of optically active constituents found over the available sample pairs. The performance of the two error indices are then assessed within an inversion algorithms applied to the same samples. The results obtained show the potential of the new error index particularly to improve the estimation of CHL concentration.

La Produzione Primaria (PP) marina si basa prevalentemente sull'assorbimento della radiazione fotosintetica attiva (PAR) da parte della clorofilla fitoplanctonica. I raggi solari attraversano la superficie marina, attivano la fotosintesi e la produzione primaria di nuova materia organica. In questo lavoro abbiamo valutato l'uso di differenti tipi di radiazione solare per la stima di PP nei mari della Toscana dal 2005 al 2008. Le tipologie di radiazione solare comprendono la radiazione misurata presso alcune stazioni meteorologiche e la radiazione stimata da osservazioni satellitari. I prodotti satellitari considerati sono i valori giornalieri di Surface Solar Irradiance (SSI), derivato dall'Ocean & Sea Ice Satellite Application Facility (O&SI SAF), e di PAR del sensore SeaWiFS, ottenuto dal sito Ocean Color della National Aeronautics and Space Administration (NASA). Un modello locale di PP è stato infine applicato con la PAR ottenuta dai due prodotti satellitari. Il confronto fra i tre tipi di radiazione mostra una debole superiorità del prodotto O&SI SAF rispetto al SeaWiFS. Il primo è, infatti, più coerente con i dati misurati nelle stazioni meteorologiche, senza mostrare i trend di degrado che sono tipici nelle misure radiometriche terrestri. Tuttavia, le differenze di PP ottenute usando i due tipi di prodotti PAR sono marginali e limitate a casi particolari. Infine, sono discusse le principali caratteristiche dei tipi di radiazione esaminati in vista di un loro possibile utilizzo all'interno di un sistema operativo per il monitoraggio della PP nell'area in studio.

Global standard ocean colour algorithms may be inefficient to estimate the concentration of seawater constituents in the Mediterranean Sea. Local overestimation or underestimation of chlorophyll, suspended sediments and yellow substance are in fact quite common. To avoid this problem, our research group works on the local calibration of empirical or semi-analytical algorithms through comparison to in situ measured data. The spectral features of chlorophyll, suspended sediments and yellow substance were found for a number of samples near the coast of Tuscany (Italy). An unconventional algorithm was then developed and applied to satellite data (MODIS) for the retrieval of water constituent concentrations. This inversion algorithm is based on the minimization of the spectral angle between simulated and measured remote sensing reflectances. The estimated concentrations show a lower error with respect to that obtained by a standard error minimization criterion. Monthly maps of seawater constituent concentrations obtained by applying the proposed algorithm to numerous satellite images confirm the oligotrophic nature of the Tuscany Sea, where high values of these concentrations can be found only in early spring near the mouths of the main rivers.

Depositional environment mapping in alluvial plains is a basic step in geomorphological, pedological and archaeologicalstudies, where remotely sensed data give an indirect contribution in assessing soil moisture, which could be correlated tosediment texture. However, a textural discrimination based on soil wetness is strictly season-dependent, and any procedure used to map different deposits from remotely sensed data falls when the acquisition time is not appropriate, and theappropriate time is generally different for the various sediments in a study area; hence the need for a multitemporal approach.In the present study a multitemporal Wetness (Tasseled Cap Transformation, TCT) analysis has been performed on the Pisaplain (Central Italy), in order to reconstruct the environment hosting a Roman harbour which seems to be one of the mostimportant Roman harbours ever discovered, as is emerging from the archaeological excavation in progress. Four geocodedand atmospheric corrected images, acquired in March, July, October and December 1991, were processed to obtain just asmany Wetness maps. Wetness multitemporal images were produced, and the seasonal changes of this parameter werecorrelated with grain-size characteristics in selected points in which the soil was bare at each flying over. A PrincipalComponent Analysis on Wetness images was also carried out and synthetic images were produced.Out of all the images, a reliable textural discrimination in the study area was obtained, together with palaeo-geographicalinformation useful in order for a better understanding ofthe role ofthe ancient harbour.Keywords: Geomorphology, archaeology, sediment texture, alluvial plain, soil, wetness, multitemporal analysis, TasseledCap Transformation, Italy.

A Landsat TM image of the Arno River mouth (Tuscany, Italy) was geocoded and atmospherically corrected in order to obtain suspended sediment concentration (s.s.c.) values. For the same day in which the image was a acquired, the river plume was simulated with MIKE 21 modeling system, given river discharge and wind speed. The suspended sediment concentration maps obtained through the two procedures were compared and eddy viscosity and dispersion coefficients were modified in order to gain the plume shape which best fits the remotely sensed one. After additional calibrations, the modeling system will be used to predict pollutant dispersion along the coast, which is intensively used for tourism.