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Aggregate re‐formation after a disturbance is important for maintaining soil hydraulic status and carbon stabilization. A study investigating the re‐formation of aggregates after disturbance by spring tillage was conducted at a site located on a south‐facing (6%) slope with a silt‐loam soil at Arlington‐Wisconsin in 2018 and 2019. Treatments were conventional tillage (CT) and no‐tillage (NT) with winter application of solid manure (SM) and no manure in a complete randomized design. Soils under NT had a higher proportion of larger aggregates (>1 mm), whereas the proportion of smaller (<1 mm) aggregates was greater under CT. Soil organic carbon, total nitrogen, bulk density, soil water retention, and micropores of NT treatments were higher compared to CT systems at 0‐ to 5‐cm depth. However, the impacts of manure application on soil properties were not significant, except for those of soil organic carbon (SOC) and total nitrogen. Harvesting in 2018 decreased the relative proportion of aggregates smaller than 1 mm and hydraulic conductivity of saturated soil. These results indicate that the immediate effect of tillage is to decrease larger aggregates, SOC, and total porosity, whereas harvesting decreases the proportion of smaller aggregates. Comparatively, aggregates smaller than 1 mm were mainly influenced by the long‐term effects of the management operations. It appears that larger aggregates can recover on an annual basis, but aggregates smaller than 1 mm do not. In long‐term studies, there is a need to monitor aggregates, including their size distribution and pore structures, to identify aggregate turnover time and rate, which will augment our understanding of aggregate formation. Core Ideas: No‐till developed larger aggregates while conventional tillage lead formation of smaller aggregates.The greater proportion of larger aggregates was linked to higher soil organic carbon (SOC), nitrogen, and bulk density (ρb).Immediate effects of management reduced soil structure due to higher ρb and lower SOC.Note that 1‐ to 4‐mm aggregates were not maintained after tillage disruption.Aggregates <1 mm cannot re‐form annually since they are related to long‐term effect. [ABSTRACT FROM AUTHOR]

The use of crop residues for biofuel production has the potential to provide environmental and economic benefits to modern societies. Because of the profound impacts that crop residues have on agricultural productivity and soil health, a sustainable utilization of these residues is required. Thus, we determined crop yield and quality response for a range of biomass retention rates in grain cropping systems. Combinations of corn (Zea mays L.) stover (0, 3.33, 6.66 and 10 Mgha−1) and wheat (Triticum aestivum L.) straw (0, 1.0, 2.0, and 3.0 Mgha−1) were soil applied in a corn-wheat/soybean (Glycine max L. Merr.) rotation in Virginia's Coastal Plain. Corn stover (0, 3.33, 6.66, 10 and 20 Mg ha−1) was applied in a continuous corn cropping system in the Ridge/Valley province. For each system, residues were applied following grain harvest over two production cycles. Each experiment was conducted as a randomized complete block design with four replications. Two cycles of crop residue management, with retention rates of up to 20 Mg ha−1 of corn stover retention in Blacksburg, and up to 13 Mg ha−1 of corn stover and wheat straw in New Kent, had no effect on total nitrogen (TN) and carbon (TC) concentrations, CN ratios, bulk density (BD), soil pH, field capacity, permanent wilting point, plant available water and water aggregate stability across soil depths and aggregate sizes in Virginia. In one situation when residue management slightly affected BD (0–2.5 cm depth, NK1), differences across the sixteen total retained residues treatments were less than 5%, thus rendering them not biologically or environmentally meaningful. Overall, results of this study did not show any clear short-term impact, resulting from various rates of crop residue retention in Virginia cropping systems. These incipient negative impacts resulting from very low rates of residue return warrant further studies to corroborate whether these results are to be found following long-term scenarios of crop residue management. [ABSTRACT FROM AUTHOR]

Simple Summary: Minimizing the effects of climate change by reducing GHG emissions is crucial and can be accomplished by truly understanding the carbon footprint phenomenon. This study aims to improve the understanding of carbon footprint alteration due to agricultural management and fertility practices. It provides a detailed review of carbon footprint management under the impacts of environmental factors, land use, and agricultural practices. The results show that healthy soils have numerous benefits for the general public and especially farmers. These benefits include being stable and resilient, resistant to erosion, easily workable in cultivated systems, good habitat for soil micro-organisms, fertile and good structure, large carbon sinks, and hence lower carbon footprint. Intensive tillage is harmful to soil structure by oxidizing carbon and causing GHG emissions. If possible, no-till; if not, minimum tillage frequency and depth of tillage, and optimum moisture are recommended. The soil should be at an appropriate level of moisture when tillage takes place. Diverse cropping systems are better for the soil than monocultures. Minimizing machinery operations can help to avoid soil compaction. Building soil organic carbon in the most stable form is the most efficient practice of sustainable crop production. Global attention to climate change issues, especially air temperature changes, has drastically increased over the last half-century. Along with population growth, greater surface temperature, and higher greenhouse gas (GHG) emissions, there are growing concerns for ecosystem sustainability and other human existence on earth. The contribution of agriculture to GHG emissions indicates a level of 18% of total GHGs, mainly from carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Thus, minimizing the effects of climate change by reducing GHG emissions is crucial and can be accomplished by truly understanding the carbon footprint (CF) phenomenon. Therefore, the purposes of this study were to improve understanding of CF alteration due to agricultural management and fertility practices. CF is a popular concept in agro-environmental sciences due to its role in the environmental impact assessments related to alternative solutions and global climate change. Soil moisture content, soil temperature, porosity, and water-filled pore space are some of the soil properties directly related to GHG emissions. These properties raise the role of soil structure and soil health in the CF approach. These properties and GHG emissions are also affected by different land-use changes, soil types, and agricultural management practices. Soil management practices globally have the potential to alter atmospheric GHG emissions. Therefore, the relations between photosynthesis and GHG emissions as impacted by agricultural management practices, especially focusing on soil and related systems, must be considered. We conclude that environmental factors, land use, and agricultural practices should be considered in the management of CF when maximizing crop productivity. [ABSTRACT FROM AUTHOR]