Relations between riverine export (load) of total nitrogen (N) and total phosphorus (P) from 133 large agricultural watersheds in the United States and factors affecting nutrient transport were evaluated using empirical regression models. After controlling for anthropogenic inputs and other landscape factors affecting nutrient transport-such as runoff, precipitation, slope, number of reservoirs...

The acreage planted in corn and soybean crops is vast, and these crops contribute substantially to the world economy. The agricultural practices employed for farming these crops have major effects on ecosystem health at a worldwide scale. The microbial communities living in agricultural soils significantly contribute to nutrient uptake and cycling and can have both positive and negative impacts...

Decisions about reducing agricultural land tillage to offset global warming potential (GWP) are based on the evaluation of the agricultural eco-system and the profitability to local farms. Carbon sequestration and nitrous oxide emissions from winter wheat (WW) cropping were evaluated by modeling typical dryland cropping systems in eastern Washington. Variations in rainfall, tillage intensity an...

A field experiment with six treatments was conducted to study the nitrogen reserves in summer maize topsoil on the north China plain. Results showed that topdressing significantly increased topsoil nitrogen reserves. Summer corn topsoil nitrogen reserves were affected by several management measures. Shallow tillage, wheat straw no-returning and deep intertillage at the corn seedling stage signi...

Soil thermal conductivity determines how a soil warms or cools with exchange of energy by conduction, convection, and radiation. The ability to monitor soil thermal conductivity is an important tool in managing the soil temperature regime to affect seed germination and crop growth. In this study, the temperature-by-time data was obtained using a single probe device to determine the soil thermal...

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 e...