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Proximal and remote sensing measurements were used to calculate different vegetation indices that were applied as predictors of gross primary production (GPP), total ecosystem respiration (TER), net ecosystem production (NEP) and leaf area index (LAI). Reflectance data and carbon fluxes were collected during the 2005 growing season at a mountain grassland site in the Italian Alps. Significant relationships were found between GPP, TER, NEP, LAI and the most commonly used spectral vegetation indices, the Normalized Difference Vegetation Index (NDVI) and Green-NDVI. Saturation of the spectral indices was evident in the estimation of both biophysical and ecophysiological parameters. Among the different indices, Green-NDVI was less affected by saturation on both a spatial and a temporal basis. Therefore, the use of an additional green-band sensor for spectral measurements at eddy covariance grassland sites is recommended. Concerning the bandwidth for the calculation of the indices, the highest predictive capacities among the sensor simulations included in the analysis were those of the Moderate Resolution Imaging Spectroradiometer (MODIS) and the high-resolution hyperspectral instrument Hyperion, indicating the advantage of narrow bands for the prediction of plant parameters. Further analyses are, however, required to investigate the relationships between NEP, GPP and vegetation indices retrieved from satellite platforms, using the bands available on MODIS and Hyperion sensors. [ABSTRACT FROM AUTHOR]

In this study, the suitability of spectral vegetation indexes for predicting green ratio (the percentage of green biomass with respect to the total phytomass) has been tested with the Italian Alps and New Zealand South Island grasslands. Considering three different datasets, green ratio (GR) was found to be negatively correlated with visible bands, while it was positively correlated in the NIR region (in total, R>0.80 in the 745-950 nm interval). GR proved to be more predictable than biomass and phytomass, both using hyperspectral single narrow bands and band ratios. Considering three different datasets, GR-index correlations were found to be linear and did not involve saturation problems. Many vegetation indices have been tested; they were well correlated with GR. Green Normalized Difference Vegetation Index (NDVIgreen) was the most stable index, with high values of R2 in all areas, low standard deviation and without significant differences in the slopes and intercepts of the linear correlations of the three datasets. [ABSTRACT FROM AUTHOR]

Abstract: Methacrylic based organic–inorganic hybrid coatings containing silica, titania or alumina domains, were generated in situ combining a UV-induced polymerization reaction with a sol–gel process of metal alkoxide precursors. While the presence of TEOS and ALP did not influence significantly the rate of curing and the final methacrylic double bond conversion, a certain effect is evident when TIP is added as inorganic precursor both on UV-curing rate and final double bond conversion. An increase of the rigidity of the cured coating was achieved in the presence of the inorganic fillers with an increase of T g values by increasing the metal alkoxide content in the photocurable formulations. Scratch test showed a general increase of first and second critical load values for hybrid coatings together with an increase in the Persoz hardness values. [Copyright &y& Elsevier]