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The aim of this paper is to enrich our knowledge of an important paleosol succession located in Bojano basin of the southern Apennines (Italy), with new pedological, geochemical and magnetic data. The studied area consists of alluvial and fluvial-lacustrine sequences (>160 m) dating from the Middle Pleistocene (0.5 Ma). The study area shows the presence of recent soil consisting of well-developed Andosols (RS), and several clastic sedimentary levels alternating with four layers (Solum I, II, III and IV) of paleosols. Soil and paleosols were analyzed by laser grain size distribution (GSD), diffuse reflectance spectroscopy (DRS), trace elements, and magnetic properties in order to evaluate the relative contributions of pedogenic and detrital components. Results showed that the finest pedogenic ferrimagnetic grains exhibit two trends with respect to the degree of pedogenesis indicate two different pedoclimate formations. The paleosol sequence consists of highly-weathered Vertisols (Solum I and IV) and of less weathered Entisols (Solum II, III). The recent soil (Andosol) has a strong bimodal distribution formed mostly by coarse silt-size particles related to the volcanic parent material. Solum I showed a sharp unimodal clay GSD while Solum III and IV were composed of bimodal GSD with high percentages of fine silt-size particles. On the basis of the trace element content and Gt/χ fd ratio, all Solum (I, II, III, IV) exhibited low weathering pedogenesis compared with RS and negligible contribution to the magnetic properties of the coarse fractions. This occurs in Vertisols which developed under humid temperate climates (Solum I and SIV) and formed below the layer of Neapolitan Yellow Tuff, developed after 12–15 ka BP. In Solum, II, III the finest sedimentary levels, the low rate of pedogenesis could have developed under more cold climatic conditions after the last eruption (Campanian Ignimbrite, 39 ka) in the Late Pleistocene. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the significance of land use on nitrate availability (NO 3 –N) at landscape scale in two different sites by using multivariate geostatistical methods. NO 3 –N and several other soil properties of Nitrate Vulnerable Zone (NVZ) monitoring network of 71 and 63 top-soils, respectively were measured in Venafro and Campomarino areas of Southern Italy (Molise region). Data analysis was performed firstly with classical descriptive statistics assuming spatial independence of samples; secondly, geostatistical analysis was performed in order to investigate spatial dependence and estimate map soil indices. The result of the distribution of NO 3 –N contents indicates the existence of many hot spots (high kurtosis) with high NO 3 –N concentration in both the study areas. Higher NO 3 –N levels in Venafro were distributed in the central zone that appeared to be correlated with animal manure applied to the fields in the summer strongly associated to high values of soil organic matter (SOM) and total nitrogen (Ntot). In Campomarino, the highest NO 3 –N concentrations occurred in random spots that appeared lesser correlated with high SOM content and low C/N ratio. Factor co-kriging analysis was applied separately to the two data sets to synthesize the complex multivariate variation of the two areas in a restricted number of zones so they could be ranked as at different risks of NO 3 –N leaching. The loading values of the factors indicate that Venafro SOM and clay and, to a lesser extent, Ntot and C/N are the variables that mainly affect the first factor at shorter range. On the other hand, cation exchangeable capacity (CEC) and, to a less extent, silt, SOM, C/N and fine sand content weighed more, but negatively, on the first factor at longer range. For Campomarino, clay content and available water capacity (AWC) and, to a lesser extent, NO 3 –N, weighed more and positively on the first factor at shorter range. The first factor at longer range was quite exclusively dominated by elevation and partially and negatively by pH and CaCO 3 . Soil factor map appears more variable in both the NVZ areas, characterized by many spots indicative of intensive land use and management. The highest NO 3 –N levels were found in intensive land use and in dairy farming located for the most part in Venafro catchment. The maps of the two factors at small scale for Campomarino appear to be quite erratic owing to the small size of the farms with different cropping systems differently managed. The results, of the present research, provide data useful to support land use planning and soil management, to mitigate soil nitrate leaching. Reduction in soil NO 3 –N could be achieved by enhancing useful recommendations in N fertilization and animal manure application to farmers. [ABSTRACT FROM AUTHOR]