Humic substances along the profile of two Typic Haploxerert

Abstract In Vertisols, organic matter contributes to soil colour by formation of organo-mineral complexes and affects morphological, physico-chemical, biological and biochemical properties. Turbation may affect the chemical and structural composition of the most stabilised fractions of soil organic matter (SOM), i.e., humic substances (HS). The objectives of this study were to: (1) characterise SOM in two Vertisols (V1 and V2) developed under Mediterranean climate in Italy, using some HS characteristics as indicators of SOM turnover in Vertisols, and (2) explore possible differences related to the pedomorphologic conditions of the area under which two soils have formed. SOM evolution along …

Differences of stabilized organic carbon fractions and microbiological activity along Mediterranean Vertisols and Alfisols profiles

This study examined the chemical and structural properties of humic substances and microbiological activity in order to verify differences in carbon dynamics along soil profiles in two Vertisols (Typic Haploxerert and Xeric Epiaquert) and two Alfisols (Mollic Haploxeralf and Ultic Haploxeralf) developed under Mediterranean climate in Italy. Humification parameters, thermal methods, including differential scanning calorimetry (DSC) and thermogravimetry (TG), together with Fourier transform infrared (FT-IR) and fluorescence spectroscopies were used to characterize humic acids (HA). Microbiological activity of soils was assessed by basal respiration, metabolic quotient (qCO2) and Cmic:Corg rat…

Energy use in the A and B horizons of the soil under a pine and a cedar stand

Publisher Summary This chapter discusses a study that compares organic carbon content, availability of substrates, and microbial metabolism in two afforested sites in Sicily (Italy) developed under the same climatic and physical conditions but underlying different tree species. Given the key role of the soil microbiota in promoting energy exchanges and transformations in the soil profile, an analysis of the microbial activity and of organic carbon pools was performed on twenty profiles. The parameters considered in this study were based on microbial activity, organic carbon fractions, and kinetics of organic C mineralization. In the two systems studied, the competition for available energy …

Soil humic acids formation and characteristics in a xeric mollisol reforested with two tree species

Publisher Summary The study discussed in this chapter examines the influence on humic acids (HAs) characteristics of different plant species—Pinus halepensis Miller and Cedrus atlantica (Endl) Carriere—used in the restoration of a Mollisol under xeric conditions. The area studied is in Sicily (Italy), and two stands were compared 40 years after planting. The differences among soil profile developments in the two stands were investigated by chemical and biochemical methods to understand the different levels at which the processes of pedogenesis acted in the study area. The chapter analyzes some chemical and spectroscopic characteristics of HAs, separated from two selected pedons. The results…

proNGF Measurement in Cerebrospinal Fluid Samples of a Large Cohort of Living Patients With Alzheimer's Disease by a New Automated Immunoassay

The discovery of new biomarkers for Alzheimer's disease (AD) is essential for an accurate diagnosis, to conceive new strategies of treatments, and for monitoring the efficacy of potential disease-modifying therapies in clinical trials. proNGF levels in the cerebrospinal fluid (CSF) represent a promising diagnostic biomarker for AD, but its validation was hampered by the absence of a reliable immunoassay. In the literature, proNGF is currently measured in postmortem brain tissue by semiquantitative immunoblot. Here we describe the development and validation of a new method to measure proNGF in the CSF of living patients. This method, based on molecular size separation by capillary electropho…

Soil Organic Matter in Mediterranean regions

Evolution of organic carbon pools and microbial diversity in hyperarid anthropogenic soils

Abstract We investigated the organic carbon pools and the microbial diversity and activity in anthropogenic terraced soils in a desert area of Southern Peru to highlight how the introduction of agriculture influences carbon evolution and storage and genetic and functional diversity of soil microbiota over time. Five sites were selected considering soils cultivated since 5, 15, 20, 35 and 65 years, sampled along the profile depth (0–20 and 20–40 cm layer). Soil and microbial parameters comprised by organic carbon pools, microbial respiration, microbial community physiological profile (CLPP) and microbial diversity (PCR-DGGE) were determined. The results showed that the highest C concentratio…