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A b s t r a c t. Application of stable isotopes in soil studies has improved quantitative evaluation of evaporation and other hydrological processes in soil. This study was carried out to determine the effect of tillage on evaporative loss of water from the soil. Zero tillage and conventional tillage were compared. Suction tubes were installed for soil water collection at the depths 0.15, 0.50, and 1.0 m by pumping soil water with a peristaltic pump. Soil water evaporation was estimated using stable isotopes of water. The mean isotopic composition of the soil water at 0.15 m soil depth were -1.15‰ (d 18 O) and -0.75‰ (dD) and were highly enriched compared with the isotopic compositions of the site precipitation. Soil water stable isotopes (d 18 O and dD) were more enriched near the surface under zero tillage while they were less negative down the profile under zero tillage. This suggests an occurrence of more evaporation and infiltration under conventional then zero tillage, respectively, because evaporative fractionation contributes to escape of lighter isotopes from liquid into the vapour phase leading to enrichment in heavy isotopes in the liquid phase. The annual evaporation estimated using the vapour diffusion equation ranges from 46-70 and 54-84 mm year -1 under zero and conventional tillage, respectively, indicating more evaporation under conventional tillage compared with zero tillage. Therefore, to reduce soil water loss, adoption of conservation tillage practices such as zero tillage is encouraged.K e y w o r d s: evaporative loss, tillage, isotopic fractionation, isotope technique INTRODUCTIONTillage is mechanical manipulation of the soil for the purpose of crop production and it affects significantly soil characteristics such as soil water conservation, soil temperature, infiltration and evapotranspiration processes. As tillage is known to cause soil surface disruption, fractionation of stable isotopes following soil tillage has been documented (Angela et al., 2009). Although tilled plots may have very high initial infiltration rate values, these rates rapidly decline with time (Guzha, 2004) probably due to intense alteration of the top centimetres of the soil (Josa et al., 2010) and rapid structural deterioration caused by slaking and dispersion. However, due to the effect of increased soil organic matter (Lipiec et al., 2006) and soil surface protection, high infiltration under zero tilled (ZT) plots have been documented (Shukla et al., 2003). According to Gupta et al. (2004) less intense tillage keeps the crop residue at the soil surface, thereby increasing the activity of surface-feeding earthworms, leaving the root channels undisturbed, leading to the presence of numerous surface-connected macro-pores and inter-pedal, hence higher infiltration. It has been reported that lower soil temperature due to higher water content in the topsoil and more plant residues on the soil surface under ZT usually result in reduced evaporation, whereas the opening of topsoil enhances evaporation from the tille...

The increase of brain dimensions and complexity has characterized the evolution of the genus Homo. According to the available fossil and genetic evidence, a crucial stage came before the divergence of Neanderthals, Denisovans and Homo sapiens, during the Middle Pleistocene. We consider a specimen of about 400 ka, whose phenotype is at the roots of this divergence: Ceprano calvarium (Italy). Here, we show a derived cerebrovascular organization with a mosaic of modern human and primitive features characteristics. Computed microtomography shows vascular variation and ontogenetic defects associated with ventricular and lymphatic involvement while phylogenetic analyzes highlight a dysregulation of the Tet1 gene that shows an accelerated mutation rate between 1.2 Ma and 466 ka, in contrast with the expected neutral evolution of the human genome. These results shed light on the dynamics of cranio-cerebral growth during the encephalization process and on the cerebral vascular and lymphatic system involved in this process. The results of this study could have implications for the research of many of the diseases of the central nervous system that have become predominant in an increasingly structured and long-lived brain system such as that of modern Homo sapiens.

The increase of brain dimensions and complexity has characterized the evolution of the genus Homo. According to the available fossil and genetic evidence, a crucial stage came before the divergence of Neanderthals, Denisovans and Homo sapiens, during the Middle Pleistocene. We consider a specimen of about 400 ka, whose phenotype is at the roots of this divergence: Ceprano calvarium (Italy). Here, we show a derived cerebrovascular organization with a mosaic of modern human and primitive features characteristics. Computed microtomography shows vascular variation and ontogenetic defects associated with ventricular and lymphatic involvement while phylogenetic analyzes highlight a dysregulation of the Tet1 gene that shows an accelerated mutation rate between 1.2 Ma and 466 ka, in contrast with the expected neutral evolution of the human genome. These results shed light on the dynamics of cranio-cerebral growth during the encephalization process and on the cerebral vascular and lymphatic system involved in this process. The results of this study could have implications for the research of many of the diseases of the central nervous system that have become predominant in an increasingly structured and long-lived brain system such as that of modern Homo sapiens. One-Sentence Summary: Genetic mutation, anatomical variations and glymphatic system in the process of encephalization towards Homo sapiens.

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