An assessment of the sensitivity at the canopy scale to leaf chlorophyll concentration of the broad-band chlorophyll vegetation index (CVI) is carried out for a wide range of soils and crops conditions and for different sun zenith angles by the analysis of a large synthetic dataset obtained by using in the direct mode the coupled PROS-PECT ? SAILH leaf and canopy reflectance model. An optimized version (OCVI) of the CVI is proposed. A single correction factor is incorporated in the OCVI algorithm to take into account the different spectral behaviors due to crop and soil types, sensor spectral resolution and scene sun zenith angle. An estimate of the value of the correction factor and of the minimum leaf area index (LAI) value of applicability are given for each considered condition. The results of the analysis of the synthetic dataset indicated that the broad-band CVI index could be used as a leaf chlorophyll estimator for planophile crops in most soil conditions. Results indicated as well that, in principle, a single correction factor incorporated in the OCVI could take into account the different spectral behaviors due to crop and soil types, sensor spectral resolution and scene sun zenith angle.

Forty-two dairy cows were subdivided in three groups of 14 cows each. Each pen of cows was provided with a feeding area, a freestall area, and an external paddock. The study was conducted in an experimental barn located in the Po Valley of Italy. The cows were observed during summer 1995 for milk yield and quality and for their behavior (movements and residence time in the different areas of each pen) under different microclimatic conditions (temperature, relative humidity, light exposure, air speed). The feeding and freestall areas were arranged with: (1) fans in the first pen; (2) fans and misting in the second pen; and 3) the third pen was used as control. During the summer months (from June to September) microclimatic conditions, milk yield, and cow position (monitored with video cameras and automatic still cameras placed in different areas of the barn) were recorded. During the hottest period, lower milk yield reductions were recorded for the cows housed in pens with fans or with fans and misting. This result was consistent with the behavior of the cows inside experimental pens that spent longer periods of resting time in the feeding and freestall areas, and showed overall behavior similar to that observed during a cooler period. Some cows also lay in the wet dirty areas of the pens or crowded in a well-ventilated place. The results of this study confirm the usefulness of cooling systems for cows in a warm climate.

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Five empirical and nonempirical parametric topographic normalization methods (the cosine, SCS, Minnaert, b correction, and c correction methods) were applied to multitemporal Landsat Thematic Mapper data (bands 1-5 and 7) collected in different periods of the growing season (April, June, and July) of a mixed deciduous forest area (340 ha) in the northern Apennines. The effectiveness of the models at removing topographic control, preserving internal data variability, and consistently normalizing radiance for flat pixels from band to band and image to image was evaluated. The entirely empirical b correction outperformed the other considered methods without relying on any photometric function.

This summer study aimed to evaluate the effect on dairy cows, kept in a free stall barn equipped with fans and sprinklers in the feeding area, of the delivery rate of misters in a cooling system in rest areas with different bedding materials. Thirty cows were divided into two homogenous groups according to milk yield and kept in two pens: one had beds with sand (SAMM) while the other had straw (STLM). Each pen was equipped with 2 fans (Ø 70 cm, 0.50 kW) and 2 misters (delivery rate of 11.2 and 22.5 L/h in STLM and SAMM, respectively) in the rest area. Microclimatic parameters, rectal temperature (RT), breathing rate (BR), milk yield, and some milk traits were recorded. Behavioural routines of the cows (standing and lying) were also continuously recorded during the hotter days. During the trial, two mild-moderate heat waves were observed. During these hotter periods, the daily maximum temperature recorded in the rest areas was 28.9 in SAMM and 31.2 in STLM, and the daily maximum THI was 78.2 in SAMM and 81.5 in STLM. In these periods, the cows in SAMM compared with those in STLM showed lower BR (P < 0.05) and greater rest time (10.2 and 7.8 h/day in SAMM and STLM, respectively). The RT did not differ (38.89 ± 0.29 and 38.88 ± 0.33°C in STLM and SAMM r,espectively). In conclusion, our research suggests that the cooling system using fans plus misters with mild wetting in rest areas with sand as bedding materials reduces heat stress and improves cow comfort.