Soil potassium depletion in global cereal croplands and its implications.

Nitrogen (N), phosphorus (P) and potassium (K) are of the most essential nutrients for crop production, and inputs of their fertilizers have been a direct and effective way to replenish their removal from crop harvest. However, the global soil K status is scarcely documented. This study attempts to evaluate the soil K deficit in global cereal croplands and potential effects of better K fertilizer management.

Estimating carbon sequestration in the piedmont ecoregion of the United States from 1971 to 2010.

Background: Human activities have diverse and profound impacts on ecosystem carbon cycles. The Piedmont ecoregion in the eastern United States has undergone significant land use and land cover change in the past few decades. The purpose of this study was to use newly available land use and land cover change data to quantify carbon changes within the ecoregion.

Ecosystem carbon stocks and sequestration potential of federal lands across the conterminous United States.

Federal lands across the conterminous United States (CONUS) account for 23.5% of the CONUS terrestrial area but have received no systematic studies on their ecosystem carbon (C) dynamics and contribution to the national C budgets. The methodology for US Congress-mandated national biological C sequestration potential assessment was used to evaluate ecosystem C dynamics in CONUS federal lands at present and in the future under three Intergovernmental Panel on Climate Change Special Report on Emission Scenarios (IPCC SRES) A1B, A2, and B1.

An estimate of carbon emissions from 2004 wildfires across Alaskan Yukon River Basin.

Background: Wildfires are an increasingly important component of the forces that drive the global carbon (C) cycle and climate change as progressive warming is expected in boreal areas. This study estimated C emissions from the wildfires across the Alaskan Yukon River Basin in 2004. We spatially related the firescars to land cover types and defined the C fractions of aboveground biomass and the ground layer (referring to the top 15 cm organic soil layer only in this paper) consumed in association with land cover types, soil drainage classes, and the C stocks in the ground layer.

Simulated responses of soil organic carbon stock to tillage management scenarios in the Northwest Great Plains.

Background: Tillage practices greatly affect carbon (C) stocks in agricultural soils. Quantification of the impacts of tillage on C stocks at a regional scale has been challenging because of the spatial heterogeneity of soil, climate, and management conditions. We evaluated the effects of tillage management on the dynamics of soil organic carbon (SOC) in croplands of the Northwest Great Plains ecoregion of the United States using the General Ensemble biogeochemical Modeling System (GEMS).