Search results for "Soil classification"
showing 10 items of 99 documents
Soil moisture influences sorptivity and water repellency of topsoil aggregates in native grasslands
2017
Abstract Water repellency is associated to coating of soil particles by hydrophobic substances, usually of organic origin, affecting water dynamics in soil matrix. We analyzed the effect of water repellency on water sorptivity of topsoil aggregates of six soil types under three initial moisture conditions (10 kPa, 100 kPa, and air-dried). Undisturbed soil samples were collected to evaluate sorptivity in the 0–5 cm soil layer at different locations in Pampa Biome in southern Brazil. Disturbed soil samples were also collected for soil particle size distribution, particle density and organic matter content. Sorptivity test was conducted in a tension micro-infiltrometer, using distilled water a…
Energy use in the A and B horizons of the soil under a pine and a cedar stand
2002
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 …
Taxonomic and environmental implication of pedotechnique in large scale farming
2016
Abstract Human activities that involve deep modifications of the soils and a substantial deterioration of their features are numerous and very diverse. Such activities are considered as pedotechniques and, in large-scale farming, are used only under the boost of significant economic returns. In these last decades, the pedotechniques used to tailor soils suitable for table vine cultivation in the Acate valley (Sicily, Italy), not only led to objective difficulties in the classification of these deeply transformed soils but also, to several environmental hazards. In this work after considering the pedotechniques used in tailoring suitable soil for table vine cultivation, we propose to introdu…
Receptiveness of some tropical soils from banana fields in Martinique to the arbuscular fungus Glomus intraradices
2000
Tropical crops of great economic importance such as banana are known to benefit from mycorrhizal association. Development and survival of introduced mycorrhizal propagules depend not only on the crops but mainly on the edaphic conditions and soil types where the symbiosis is established. Seven soils from banana fields of Martinique were sampled and tested to determine their receptiveness to mycorrhizal inoculation. Biological tests involved cultivation of 10 leek plantlets in pots containing soil inoculated with a range of mycorrhizal propagule densities (3, 10, 30, 100, 300 propagules/100 g soil). Mycorrhizal colonisation was recorded after 2 weeks of growth and tentatively correlated with…
Soil DNA evidence for altered microbial diversity after long-term application of municipal wastewater
2010
International audience; Water resources constitute a social, agricultural and economic problem in most countries of the southern Mediterranean Basin. Alternative strategies have been developed such as the reuse of municipal wastewater for irrigation in agriculture. Despite numerous advantages for soil fertility and crop productivity, recycling wastewater in soils also has several ecotoxicological and sanitary problems. Few investigations have assessed the risk by evaluating the impact of wastewater irrigation on soil microbes. Here, we report for the first time the short- and long-term effects of treated municipal wastewater irrigation on the density and genetic structure of bacterial and f…
Spatio-Temporal Effects of Land Use Change on the Anthropogenic Soils Diffusion: A Case Study in a Mediterranean Vineyard Area
2008
Anthropogenic soils created ex novo by land-use change in large scale farming are, from a pedogenetic point of view, catastrophic events that bring the soils to time zero and change the natural pattern of the soilscape, remarkably, in some cases. The quantitative aspects of pedodiversity of a soilscape in South-East Sicily, where some types of soils, in recent decades, have suffered a consistent reduction due to the transformations by large scale farming, are considered. The evolution of pedodiversity over a 53-year period (1955 to 2008) is examined using a dedicated statistical method and a space–time model based on Markov analysis and cellular automata in order to predict the evolution of…
Soil interpretation in the context of anthropedogenic transformations and pedotechniques application
2018
Abstract Following a long and vigorous study carried out by the International Committee on Anthropogenic Soils (ICOMANTH), the Soil Taxonomy (ST) classification system recently incorporated a number of changes to include Human-Altered and Human-Transported soils, generally called anthropogenic soils. These changes underwent careful scrutiny as they affect the current classification of existing soil series, and as the proposals and logics are as yet untested against existing data and descriptions. Particular attention was given to the diagnostic characteristics of the anthropogenic soils and to the Subgroups for Human-Altered and Human-Transported soils. In this study, we consider a frequent…
Modeling of 137Cs migration in soils using an 80-year soil archive: role of fertilizers and agricultural amendments
2008
An 80-year soil archive, the 42-plot experimental design at the INRA in Versailles (France), is used here to study long-term contamination by 137Cs atmospheric deposition and the fate of this radioisotope when associated with various agricultural practices: fallow land, KCl, NH4(NO3), superphosphate fertilizers, horse manure and lime amendments. The pertinence of a simple box model, where radiocaesium is supposed to move downward by convectional mechanisms, is checked using samples from control plots which had been neither amended, nor cultivated since 1928. This simple model presents the advantage of depending on only two parameters: α, a proportional factor allowing the historical atmosph…
Effects of soil compaction, rain exposure and their interaction on soil carbon dioxide emission
2012
Soils release more carbon, primarily as carbon dioxide (CO2), per annum than current global anthropogenic emissions. Soils emit CO2 through mineralization and decomposition of organic matter and respiration of roots and soil organisms. Given this, the evaluation of the effects of abiotic factors on microbial activity is of major importance when considering the mitigation of greenhouse gases emissions. Previous studies demonstrate that soil CO2 emission is significantly affected by temperature and soil water content. A limited number of studies have illustrated the importance of bulk density and soil surface characteristics as a result of exposure to rain on CO2 emission, however, none exami…
Soil solarization with biodegradabile materials and its impact on soil microbial communities.
2008
Soil solarization (SS) seems one of the most promising techniques to control soilborne pathogens, but an important limitation to the diffusion of this technique is due to the drawback regarding the disposal of the used plastic materials. A possible solution to this problem is the use of biodegradable plastics. The aim of this study was compare the impact of SS with biodegradable materials with SS with plastic film and others pest management techniques (i.e. organic matter amendment, calcium cyanamide and Dazomet fungicide application) on crop productivity, soilborne disease incidence, weed suppression, and soil chemical (total N, ammonium, nitrate, available phosphorus, organic matter, hydr…