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Removal of crop residues for biofuel production can potentially increase the erodibility of a soil by not only exposing the soil surface to winds but also affecting changes in soil aggregation and roughness. Field studies at both Colby and Ottawa, Kansas were conducted to determine the effects of long-term residue removal on soil wind erodibility. Corn residue was removed from plots at 0%, 25%, 50%, 75%, and 100% levels beginning in 2009. Soil aggregate status and random roughness were measured in both the spring and fall from 2017 through 2020. As removal levels increased, the soils studied tended to have smaller aggregates and less rough surfaces, both of which increase soil erodibility. For many spring measurements, significant differences were found between the 0% removal levels and the 100% removal levels for soil erodible fraction (EF) and geometric mean diameter (GMD). We also used measured soil properties, weather, and yields as inputs into the WEPS and SWEEP models to simulate potential wind erosion at the study sites. Simulation results indicate that wind erosion can occur whenever soil cover falls below 50% with removal levels of 25% showing wind erosion loss in one case. Results of this study provide general guidance for regional and private sector land managers regarding levels of corn biomass that can be sustainably harvested and still control soil wind erosion. • Wind erosion parameters were measured on two residue removal sites in Kansas. • Aggregate size parameters tended to decrease with increasing residue removal levels. • Simulations show that wind erosion can occur whenever soil cover falls below 50%. • Losses in excess of tolerable levels can be expected as residue removal approaches 100%. [ABSTRACT FROM AUTHOR]

Urban gardening has been experiencing increased popularity around the world. Many urban gardens are located on sites that may be contaminated by trace elements or organic compounds due to previous use. The three main exposure pathways to the human body for soil contaminants are (a) ingestion of soil directly, (b) consumption of produce containing or superficially contaminated with a contaminant, (c) and inhalation of soil dust. The first two modes have received much attention; however, the contribution of the inhalation route has not been investigated adequately. Two inhalation risk studies were carried out in urban gardens located in Kansas City, MO, by collecting dust while 25-m 2 plots were rototilled. Microclimatic variables were monitored, and total inhalable dust mass was determined using a personal sampling train including a small pump and air filter. Soil lead (Pb) concentration was assessed at both sites. For Study 1, particle size distribution of collected particles was estimated through analysis of scanning electron microscope images of filters. Little dust was collected at either site. Most particles captured, however, appeared to be <4 μm in diameter. The amount of dust emitted was correlated with soil moisture. Tilling reduced soil aggregate size and blended soil, resulting in a more homogeneous distribution of Pb. Dust inhalation while tilling is likely not a major Pb exposure risk for gardeners, but given the preponderance of very small particles in what was captured, care should be taken to prevent dust from entering the respiratory system., (© 2021 The Authors. Journal of Environmental Quality © 2021 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)