Search results for "soil"
showing 10 items of 3493 documents
Carbon stocks in a 50‑year‑oldEucalyptus camaldulensisstand in Sicily, Italy
2015
Eucalyptus stands in semi-arid areas may contribute to enhance carbon (C) stocks in both biomass and soil. However, the limited information available is mainly focused on short-rotation plantations. In this study, the above- and below-ground C pools in five 50-year-old Eucalyptus camaldulensis Dehnh. stands planted on Miocenic evaporitic deposits in Sicily, Italy, with a xeric and thermic pedoclimate, were measured. Above-ground biomass was determined by partitioning and weighing branches, stem and leaves. Below-ground C pools included the determination of litter, root biomass, and soil organic and inorganic C. In terms of the above-ground biomass, the E. camaldulensis stand accumulated on …
Is it possible to understand a book missing a quarter of the letters? Unveiling the belowground species richness of grasslands
2022
Abstract Knowledge of species richness patterns in plant communities is biased toward its hidden belowground part and is derived only from the part visible aboveground. Studies on the relationship of the above- to belowground parts of plant communities suffer from the lack of a consistent and uniform approach to assess their taxonomic composition, particularly in species-rich ecosystems. This study described the proportion between above- and belowground parts of vegetation in three grassland types along with the environmental factors that affect them, using eDNA metabarcoding and an observer survey. The internal transcribed spacer 2 (ITS2) region was used to analyze the total plant richness…
Evolution des paysages Sahélines au cours des six dernières décennies dans la région de Niamey : de la disparition de la brousse tigrée à l'encroutem…
2010
In the Sahel, the rapid increase of the population during the last decades and the climate variation lead to an important environmental degradation. This work aims to measure the impacts of the human pressure on ecosystem during the six last decades. A diachronic cartography of a 100 km² area close to Niamey was done with aerial photographs (1950 and 1975) and GPS measurements (2009). Results showed that the tiger bush vegetation was completely cleared between 1950 and 2009 while the fallow decreases from 7 % to 1 %. In the sandy valley, the increase of cultivated fields from 20,7 % (1950) to 69,4 % (1975) favoured wind and water erosions which allowed surface soil crusting. Between 1975 an…
Spatial data fusion and analysis for soil characterization: a case study in a coastal basin of south-western Sicily (southern Italy)
2012
Salinization is one of the most serious problems confronting sustainable agriculture in semi-arid and arid regions. Accurate mapping of soil salinization and the associated risk represent a fundamental step in planning agricultural and remediation activities. Geostatistical analysis is very useful for soil quality assessment because it makes it possible to determine the spatial relationships between selected variables and to produce synthetic maps of spatial variation. The main objective of this paper was to map the soil salinization risk in the Delia-Nivolelli alluvial basin (south-western Sicily, southern Italy), using multivariate geostatistical techniques and a set of topographical, phy…
The influence of coconut fibre and salts composite used for eliminating slipperiness and on roads on soils = Wpływ kompozytu mieszanki włókien kokoso…
2015
The subject of the study is analyzing the impact of coconut fibre and salt mixture used for eliminating slipperiness on roads on roadside soil. The tests were done on the soil samples taken from the fixed areas twice: in the autumn before applying the composite and in the following spring. Laboratory tests indicated decrease of conduciveness in soil after using the composite in wintertime. This can cause decreasing saltiness of roadside soil. In contrast to commonly used methods of eliminating slipperiness on roads with salts only applying the composite could diminish the negative effects of roadside soil saltiness.
Combined effect of low-molecular-weight organic acids and creosote on phosphatase activities in sandy soil
2018
This paper assesses the impact of creosote and low-molecular-weight organic acids (LMWOAs) on the activity of acid phosphomonoesterase, alkaline phosphomonoesterase, phosphotriesterase, and inorganic pyrophosphatase in soil. The experiment was carried out on loamy sand samples with organic carbon content of 8.71 g · kg -1 , with the following variable factors: dosages of creosote: 0, 0.5%, and 2.5%; type of LMWOAs: oxalic acid, tartaric acid, and citric acid in the amount of 50 mmol · kg -1 of soil; days of experiment: 1, 7, 14, 28, 56, 112. Obtained results showed that contamination with creosote caused decrease in the activity of soil phosphatases. The observed effect did not always incre…
PLOT LENGTH EFFECTS ON RUNOFF AND SOIL EROSION AT THE SPARACIA EXPERIMENTAL SITE
2018
Explaining scale effects for runoff and erosion improves our understanding of erosion processes. In this investigation, plot length effects on event runoff per unit area, Qe, sediment concentration, Ce, and soil loss per unit area, SLe, were checked at the Sparacia (Italy) site. The most common result, occurring for the 57-62% of the events depending on the considered variable, was the lack of any scale effect. When scale effects were detected, they indicated that longer plots yielded smaller Qe and SLe values and higher Ce values. Rainfall characteristics did not explain the occur-rence of significant scale effects nor they were able to describe changes in the scaling exponent for Ce and S…
Dynamics of soil organic matter pools after agricultural abandonment
2014
Changes of land use from croplands to natural vegetation usually increase Carbon (C) stocks in soil. However, the contribution of old and new C to various pools still is not clearly analyzed.We measured the 13C signature of soil organic carbon (SOC) pools after vegetation change from vineyard (C3) to grassland (C4) under Mediterranean climate to assess the changes of old and new C in total SOC, microbial biomass (MB), dissolved organic C (DOC), and CO2 efflux from soil. Development of the perennial grass Hyparrhenia hirta (C4) on vineyard abandoned for 15 or 35 years ago increased C stocks for 13% and 16%, respectively (in the upper 15 cm). This increase was linked to the incorporation of n…
Testing the Modified Sediment Delivery Model (MOSEDD) at SPA2 Experimental Basin, Sicily (Italy)
2017
A new version of a spatially distributed sediment delivery model taking into account the hillslope sediment transport efficiency, named MOSEDD, is presented. This model gives estimates of basin sediment yield at event scale, which are more reliable than those obtained by the original SEDD. For SPA2 basin discretized into morphological units, four different calculation schemes of MOSEDD, including the original SEDD version, were applied. All parameterization schemes of the model were calibrated using 15 events measured at the outlet of the experimental basin in the period February 2005–February 2010. The model calibration was used to determine a relationship between the coefficient βe of the…
Rainwater-induced leaching of selenium, arsenic and vanadium from Etnean volcanic soils
2009
Active volcanoes emit considerable amounts of contaminants such as As, Se and V. Mount Etna is the biggest volcano of Europe and an excellent geochemical site to study water-soil processes. Due to its volcanic activity, the rainwater has a strong compositional gradient, both in time and space. At present, the behaviour of trace elements in the soils around Mt Etna is poorly understood. To determine the influence of the rainwater pH on the potential mobilization of geogenic pollutants, batch experiments have been performed with synthetic rainwater for 25 soils collected along the flanks of the volcano. Our results show that: i) The maximum concentrations in the leaching solutions are higher …