Methods of soil analysis.

TL;DR: In this paper, the authors used isotope dilution to determine the gross production and oxidation rates of CH4 after 2 days incubation under oxic headspace conditions, and after 2, 21 and 60 days under anoxic conditions.

TL;DR: Urea amended with clinoptilolite zeolite and compost significantly reduced NH4 + and NO3 − release from urea compared with urea alone, thus reducing leaching of these ions.

TL;DR: In this paper, the authors quantify the carbon content of soils with differ-ent textures and with high iron and aluminum concentrations using LIBS, and the results indicated that LIBS quantification can be affected by the texture and chemical composition of soil.

Abstract: Saline‐sodic soils comprise a large area worldwide, and these areas are increasing annually; therefore, reclamation of these soils is necessary. The present study investigated the effects of adding various biochars and acidified biochars on selected characteristics of saline‐sodic soil and rehabilitation of this soil. The biochars were produced from rice straw (RSB) and dicer wood chips (DWCB) at 300°C. The acidified biochars were prepared by adding HCl to the biochars. The biochars and acidified biochars were incorporated to the soil at 0 and 50 g kg−1. Soil columns were prepared and saturated from the bottom, and then the flow was reversed by keeping a 5‐cm constant head of leaching water on top of the columns. The leachates were taken at every one‐third interval of the pore volume fraction. Then, the concentrations of cations and anions, pH, and electrical conductivity (EC) of the collected leachates were determined. At the end of the leaching process, the soil in the column was analyzed for the same parameters as the leachates. The results indicated that the application of the biochars and acidified biochars reduced the soil EC and sodium adsorption ratio. The biochars, especially the RSB, which contains a high amount of Ca2+ and Mg2+, were able to remediate the saline‐sodic soil. The Ca2+ and Mg2+ in the biochar can exchange the Na+ on the surface of the soil colloids and, therefore, enhance the Na+ leaching from the saline‐sodic soil. Acidified biochar induced CaCO3 dissolution, which will add Ca2+ and H+ ions to soil solution. The Ca2+ and H+ ions in the soil solution replace the Na+ from the soil colloid surfaces and facilitate the leaching of Na+ from the saline‐sodic soil. From the results, it can be concluded that RSB, acidified RSB, and acidified DWCB were feasible to ameliorate calcareous saline‐sodic soil.

TL;DR: In this paper, the authors present a modeling approach aimed at seasonal resolution of global climatic and edaphic controls on patterns of terrestrial ecosystem production and soil microbial respiration using satellite imagery (Advanced Very High Resolution Radiometer and International Satellite Cloud Climatology Project solar radiation), along with historical climate (monthly temperature and precipitation) and soil attributes (texture, C and N contents) from global (1°) data sets as model inputs.

TL;DR: In this paper, the Century ecosystem model was applied to a series of forest and grassland sites distributed globally to examine large-scale controls over soil carbon, including soil texture and foliar lignin content.

TL;DR: In this article, the Rothamsted model is used to calculate the amount of CO2 that would be released from the world stock of soil organic matter if temperatures increase as predicted, the annual return of plant debris to the soil being held constant.

TL;DR: In this paper, the formation of soil structure involves the physical forces of shrinking and swelling created by changes in water status of soils, freezing and thawing, tillage, or by movement of the larger biota in soils.