It is unclear why atmospheric oxygen remained trapped at low levels for more than 1.5 billion years following the Paleoproterozoic Great Oxidation Event. Here, we use models for erosion, weathering and biogeochemical cycling to show that this can be explained by the tectonic recycling of previously accumulated sedimentary organic carbon, combined with the oxygen sensitivity of oxidative weather...

soil organic matter is an indicator of soil, agriculture and environmental quality, playing important roles in soil strength and sound environmental functions. size and chemical fractionation of soil organic matter are long-standing approaches in clarifying their key role in soil processes. twenty seven surface samples (0-20 cm) and 6 pedons from different landform units were sampled and descri...

In order to evaluate the dynamics of carbon storage during forest succession and explore the significance of water relations and soil stability in forest environments, a study was conducted in 2011. This study investigated the dynamics of soil organic carbon (SOC) fractions and its protection through aggregation along the successional forests. An experiment in South China examined pine forest (...

the effect of european black alder (alnus glutinosa l.) on the contents of carbon and nitrogen,exchangeable base cations, and plant available forms of phosphorus in the reclaimed mine soils formed bywaste deposition from opencast lignite mines was researched in central serbia. it was concluded that thegreatest part of dead organic residues reaching the soil under european black alder monocultur...

using the cropping operations program can significantly save fuel consumption and energy efficiency. prediction of the accurate amount of fuel requirements for tillage operation of the soil is difficult. changes in humidity, soil type and tillage depth directly affects on the amount of fuel consumption. bulk density of agricultural soils depends on tillage methods, the value of organic matter, ...

We evaluated the potential of prairie wetlands in North America as carbon sinks. Agricultural conversion has resulted in the average loss of 10.1 Mg ha(-1) of soil organic carbon on over 16 million ha of wetlands in this region. Wetland restoration has potential to sequester 378 Tg of organic carbon over a 10-year period. Wetlands can sequester over twice the organic carbon as no-till cropland ...

Soil organic carbon is a key soil property related to soil fertility, aggregate stability and the exchange of CO2 with the atmosphere. Existing soil maps and inventories can rarely be used to monitor the state and evolution in soil organic carbon content due to their poor spatial resolution, lack of consistency and high updating costs. Visible and Near Infrared diffuse reflectance spectroscopy ...

Introduction Conclusions References

Introduction Conclusions References