Terrain analysis,erosion simulations,and sediment fingerprinting: a case study assessing the erosion sensitivity of agricultural catchments in the border of the volcanic plateau of Southern Brazil

Journal of Soils and Sediments - Erosion and its spatial distribution in three agricultural headwater catchments were assessed in the border of the volcanic plateau in Southern Brazil. We analyzed...     

Phosphorus application and liming effects on forage production,floristic composition and soil chemical properties in the Campos biome,southern Brazil

Studies of responses of native and introduced grassland species to lime and phosphorus (P) applications could contribute to improved understanding of the potential production of South American natural grasslands. To determine the effect of applying lime and different P sources on forage production, diversity and floristic composition, and on soil chemical properties, a small‐plot experiment was conducted over 12 years in natural grassland oversown with Lolium multiflorum and Trifolium vesiculosum in the Campos of southern Brazil. In treatments with soluble phosphate application, dry‐matter (DM) yield in November 2008, after 164 d of winter and early spring growth, increased from 2·3 to 3·2 t ha^?1. Differences in DM yield in March 2009, after 111 d of growth during late spring and early summer, were not significant. The DM yield in April 2010, after 419 d of growth, increased from 7·7 to 9·2 t ha^?1 in the treatments with P, regardless of the P source. Increased forage yield during the slow growth period in winter was only possible with the introduction of winter‐growing species (L. multiflorum and T. vesiculosum) and soluble phosphate application. Assessment of annual forage yield showed that the effectiveness of Gafsa rock phosphate was equivalent to that of soluble phosphates in the long term. Soluble phosphates and liming modified the botanical composition of natural Campos grassland in the long term, but floristic diversity was not altered.     

Dynamics of sulfate and basic cations in soil solution as affected by gypsum fertilization in an Ultisol of Southern Brazil

ABSTRACT

The objective of this study was to evaluate the short-term dynamics of chemical species of sulfate and the main basic cations in the soil solution affected by the application of different sulfur (S) rates using agricultural gypsum. The experiment was carried out in an Ultisol with 14% clay, managed under no-tillage for 14 yrs in Southern Brazil. Four rates of S (0, 5, 10 and 20 kg of S ha^?1) were evaluated using agricultural gypsum (CaSO₄) as S-source. The soil solution was collected using porous capsule lysimeters before and at 9, 17, 37, 60, 76 and 109 d after the gypsum application, at depths of 20 and 60 cm. Surface application of gypsum rapidly increases the sulfate concentration in the soil solution at 20 cm depth. However, in less than 30 d, the effect of the S rates on the soil solution at 20 cm was minimal, with an increase in sulfate concentration in the soil solution at 60 cm depth after 17 d. Sulfated fertilization via agricultural gypsum at rates greater than 10 kg ha^?1 in sandy soil with low cation exchange capacity increased the mobility of Ca and Mg in the soil profile.     

Geochemistry and mineralogy of southwestern Lake Superior sediments with an emphasis on phosphorus lability

Journal of Soils and Sediments - The lability of phosphorus (P) in Lake Superior sediments and its relationship with sediment mineralogy and geochemistry remains poorly understood. The purpose of...     

Sediment source fingerprinting: benchmarking recent outputs,remaining challenges and emerging themes

Journal of Soils and Sediments - This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international...     

Using spectrocolourimetry to trace sediment source dynamics in coastal catchments draining the main Fukushima radioactive pollution plume (2011–2017)

Journal of Soils and Sediments - Spectrocolourimetric measurements provide a relatively inexpensive, quick and non-destructive alternative to the analysis of geochemical and organic matter...