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Permanganate Oxidizable Carbon Reflects a Processed Soil Fraction that is Sensitive to Management
Permanganate oxidizable C (POXC; i.e., active C) is a relatively new method that can quantify labile soil C rapidly and inexpensively. Despite limited reports of positive correlations withExpand
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Sources of nitrate yields in the Mississippi River Basin.
Riverine nitrate N in the Mississippi River leads to hypoxia in the Gulf of Mexico. Several recent modeling studies estimated major N inputs and suggested source areas that could be targeted forExpand
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Replacing bare fallows with cover crops in fertilizer-intensive cropping systems: A meta-analysis of crop yield and N dynamics
The availability of Haber-Bosch nitrogen (N) has permitted agricultural intensification and increased the productive capacity of agroecosystems; however, approximately 50% of this applied fertilizerExpand
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Nutrient Imbalances in Agricultural Development
Nutrient additions to intensive agricultural systems range from inadequate to excessive—and both extremes have substantial human and environmental costs. Nutrient cycles link agricultural systems toExpand
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Legume-based cropping systems have reduced carbon and nitrogen losses
In agricultural systems, optimization of carbon and nitrogen cycling through soil organic matter can improve soil fertility and yields while reducing negative environmental impact. A basic tenet thatExpand
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Fundamental Differences Between Conventional and Organic Tomato Agroecosystems in California
In an integrated, multidisciplinary study we compared ecological characteristics and productivity of commercial farms categorized as either organic (ORG) or conventional (CNV) based on their use ofExpand
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Nutrients in agroecosystems: Rethinking the management paradigm
Agricultural intensification has greatly increased the productive capacity of agroecosystems, but has had unintended environmental consequences including degradation of soil and water resources, andExpand
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Short‐Term Dynamics of Root‐ and Shoot‐Derived Carbon from a Leguminous Green Manure
Although roots are an important source of soil organic matter (SOM) and are thought to be the major constituent of the particulate organic matter (POM) fraction, few studies have documented the fateExpand
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The fate of nitrogen in grain cropping systems: a meta-analysis of 15N field experiments.
Intensively managed grain farms are saturated with large inputs of nitrogen (N) fertilizer, leading to N losses and environmental degradation. Despite decades of research directed toward reducing NExpand
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Effect of tillage and farming system upon VAM fungus populations and mycorrhizas and nutrient uptake of maize
Low-input agricultural systems that do not rely on fertilizers may be more dependent on vesicular-arbuscular mycorrhizal [VAM] fungi than conventionally managed systems. We studied populations ofExpand
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