introduction: iron cycle is one of the most important biogeochemical processes which affect the availability of iron in soils. ferric iron oxides are the most abundant forms of iron in soils and sediments. ferric iron is highly insoluble at circumneutral ph. present investigations have shown that the structural ferric iron bound in clay minerals is reduced by some microorganisms. anaerobic bact...

The mineralization of [14C]acetate was studied in bottles with fresh soil and groundwater. Addition of toxicants inhibited the formation of 14CO2 and dose-effect curves were obtained. The acetate mineralization was not inhibited by zinc, cadmium, K2Cr2O7, chloropyrifos, and paraquat in an acid sandy soil at 1000 mg/kg dry soil. The IC10 is the toxicant concentration which inhibits 10% of the in...

Dating of prehistoric anthropogenic earthworks requires either excavation for archaeological artifacts or macroscopic organic matter suitable for 14C analysis. Yet, the former, in many cases, is undesirable and the latter is difficult to obtain. Here we present a soil science procedure, which has the potential to overcome these problems. It includes careful sampling of buried former soil surfac...

As potent allelochemicals, phenolic acids are believed to be associated with replanting disease and cause microflora shift and structural disorder in the rhizosphere soil of continuously monocultured Radix pseudostellariae. The transcriptome sequencing was used to reveal the mechanisms underlying the differential response of pathogenic bacterium Kosakonia sacchari and beneficial bacterium Bacil...

Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it is believed to potentiall...

Afforestation plays an important role in soil protection and ecological restoration. The objective of this study is to understand the effect of afforestation on soil carbon and soil microbial communities in the Loess Plateau of China. We measured two chemically-separated carbon fractions (i.e., humic acid, HA, and fulvic acid, FA) and soil microbial communities within shrublands (18-year-old Ca...

Soil fluxomics analysis can provide pivotal information for understanding soil biochemical pathways and their regulation, but direct measurement methods are rare. Here, we describe an approach to measure soil extracellular metabolite (amino sugar and amino acid) concentrations and fluxes based on a 15N isotope pool dilution technique via liquid chromatography and high-resolution mass spectromet...

BACKGROUND AND PURPOSE Forest soil microorganisms and fauna decompose the organic materials, and thus strongly influence the nutrient cycling of the ecosystem. Soil microorganisms also contribute to soil structure and soil fertility. In Taiwan, the microbial distributions of soils have only been determined in acidic soil, inorganic acidic soil, upland soil, alkaline soil and power plant areas. ...

Ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and other synthetic polycarboxylic acids have been shown to possess substantial capacity as washing agents of heavy metal-polluted soils, but they are environmentally problematic. Therefore, a sample of natural soluble humic substances (HS) was tested as a possible substitute. The efficiency of HS to extract cadmium (Cd), copp...