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In the last decades, a growing interest in fostering advanced interdisciplinary studies is leading to the establishment of observatories in pilot catchments for long-term monitoring of hydrological variables and fluxes. Nevertheless prior to sensor network installation, this investment necessitates preliminary surveys on key-variables such as near-surface soil moisture in order to prevent risks of erronously distributing sensors by missing sufficient spatial information for understanding hydrological processes within the landatmosphere interactions. The availability of maps describing areas with similar morphological, topographical, soil, and vegetation characteristics enable preliminary surveys to be organized for capturing spatio-temporal variability of soil moisture as best as possible. The soil-landscape classification can be considered as an interesting approach for grouping mapping units with similar hydrological behavior. Therefore, we assume the soil-landscape units as hydrotopes or hydrological similar units. Six transects were established along two hillsides of the Upper Alento River catchment (southern Italy) which is a proper candidate to become a Critical Zone Observatory. In this paper we use a soil-landscape map to infer spatial and temporal dynamics of soil moisture measured along these transects, whereas quantitative analyses were obtained by using multivariate techniques. The effectiveness of available information on soil-landscape mapping units is evaluated with respect to different observed patterns of soil moisture: wetter- and drier-than average observation points belong to agricultural and forested hillslopes, respectively. Soil texture and topographical controlling factors, especially clay content and slope gradient, are found to explain approximately 70% of the observed spatial variations in soil moisture along the forested hillslopes. The spatial structure explained by the environmental controlling factors decreases to 45% in the cases of the agricultural hillslopes mainly due to perturbations induced by grazing and tillage practices.

Cultivation of vegetables under plastic tunnels is a steadily growing farming system, nevertheless there are concerns about its environmental sustainability. This work tests a new cultivation system based on the application of photo-selective mulching films to the soil combined with beneficial microbes to improve crop yield, save irrigation water and enhance crop irrigation water productivity. A two-year project was carried out in three farms of southern Italy that practice cultivation in greenhouses with different soil characteristics. Photo-selective mulching films (PS) were used alone or in combination with microbial consortia (M) containing beneficial microbes (i.e. antagonistic fungi of the genus Trichoderma, mycorrhizal fungi of the genus Glomus and the plant growth promoting bacterium Bacillus subtilis) and compared with black plastic mulching (B). Soil temperature, soil water content, and irrigation water volumes were continuously monitored for eight cropping cycles including tomato, sweet pepper, lettuce, melon, and kohlrabi. Crop yields were assessed at the end of each cycle. PS films in combination with M significantly increased crop yields with respect to control, with the most positive effects on winter crops. Soil temperature under PS was consistently lower than that under B mulch. All mulching films allowed the saving of irrigation water compared with untreated control, but no difference was detected between PS and B. However, PS increases crop irrigation water productivity (CIWP) compared with B film in 25% of the experimental cases. In conclusion, our results indicate that combining PS films with beneficial microbes in cultivation under plastic tunnel greenhouses promotes crop yield and increases CIWP compared with control in 87.5% and 75% of the study cases, respectively.