Papers 8347
1 page of 835 pages (8,347 results)
Abstract Podzolization imparts soils and landforms of the southeastern United States Coastal Plain with two distinct pools of organic carbon (C), referred to as shallow podzolized C (SPC) and deep podzolized C (DPC). We evaluate podzolization across two catenas, and across the state of Florida, to establish that SPC and DPC are morphologically and hydrologically distinct. We demonstrate that SPC lightens downward (i.e. a Bh horizon with a darker top than bottom) and accumulates below low chroma ...
Abstract Over the last decade, computed tomography (CT) images have been used increasingly to gain a more complete understanding of the microscale parameters that control the soil processes. Images that are used for that purpose typically are subjected to a number of successive treatments. This article evaluates for a sandy-loam soil, the impact of two CT scan resolutions (26 and 54 μ m), three noise reduction levels, four settings of conversion from a 32-bit to an 8-bit image and four segmentat...
Abstract The presence of Hg in soil fractions of different size in eight illuvial horizons of podzols from SW Europe and five from southernmost America was studied. Total Hg concentration (HgT) in the bulk soil was very variable, ranging from 11 to 293 ng g−1, attributed to a different intensity of the pedogenetic and weathering processes. The clay fraction showed the highest HgT average with 509 ng g−1 (range 93–2076 ng g−1), followed by the fine silt with a mean of 222 ng g−1 (range 38–836 ng ...
Abstract Soil available water capacity (SAWC) is a key soil function for plant growth. Classical SAWC characterization requires time consuming determinations of bulk density and specific soil moisture contents. Consequently, these data are extremely sparse in existing soil databases. Using surrogates of the vegetal response to characterize SAWC across a great number of sites constitutes a promising perspective. The carbon isotope ratio (δ13C) measured in a plant organ is largely known as an indi...
Abstract Biochar additions may mitigate N2O emissions from soil. The mechanisms underpinning the mitigation of emissions remain to be elucidated. A series of incubation experiments were performed to investigate the effects of biochar on N2O production and reduction in columns with a low-fertility or high-fertility soil, with or without the injection of N2O in the subsoil and with and without glucose (to stimulate denitrification). Biochar was added to the calcareous soils in 0 and 1% (w/w) amoun...
Abstract Prediction and mapping of soil properties for different soil depths can provide important information for effective land management. Such predictions and maps are often built based on soil data from multiple soil surveys, and the sampled depths will rarely align with depths for which the predictions and maps are required. A recently proposed approach to deal with such datasets, termed increment-averaged kriging (IAK), fits a single model using data from all profiles and all soil depths....
Abstract Selenium biofortification of crops is a proven technology for improving dietary nutrition. This study used isotopically labelled selenate (>99% enriched 77Se) to assess uptake and Se availability to two green vegetables, Brassica napus L (B. napus) and Amaranthus retroflexus L (A. retroflexus) grown in three contrasting Malawi soils: a Vertisol (calcareous), Alfisol (moderately acidic) and Oxisol (acidic). Plants were grown under glasshouse conditions (4 replicates; 6 kg soil per pot) f...
Abstract Amazonian Dark Earths (ADEs) are soils studied for archaeological purposes and as a potentially agricultural model for the humid tropic. We investigated the chemical composition of an ADE in comparison to an adjacent Ultisol without anthropic influence for better understanding the origin of ADE fertility and formation process. Three hundred ADE and Ultisol samples were collected at 10 cm depths from 0 to 100 cm soil profiles on the Caldeirao site at the Solimoes River, Brazil and analyz...
Abstract Soil sodicity and salinity are global issues associated with irrigated and non-irrigated land management. The combination of high sodium adsorption ratio (SAR) and low electrical conductivity (EC) of the soil solution decreases the saturated hydraulic conductivity of soils. Unfortunately, there have been few attempts to model the changes in saturated hydraulic conductivity in response to EC and SAR. The objectives of this study was to analyze previously developed functions to predict ch...
Abstract Soil acidity plays a central role in the diversity and function of terrestrial ecosystems. Recent studies have revealed that acid deposition has acidified topsoil over time. However, uncertainties relating to how the acidity of the entire soil profile, including deep soil, responds to multiple global change drivers make it challenging to predict the effects of the ongoing global change on soil functions. Using data from 2952 observations of 200 montane sites in subtropical China, we sho...
Top fields of study
Soil horizon
Soil science
Soil water