It is essential for the sustainable development of agriculture to enhance nitrogen use efficiency (NUE) of crop plants by increasing yield and reducing nitrogen (N) losses. Biochar-based fertilizer (BF) has received increasing attention because of its full play to the advantages of chemical compounds with sufficient N and less N loss risk with good adsorption characteristics, but this potential was seldom reported for open-field vegetable crops, NUE of which were significantly lower than cereal crops. A field trial was conducted to investigate the efficacy of BF on NUE in vegetable cropping system by comparison with chemical fertilizer (CF) and partial substitution of organic fertilizers to chemical fertilizers (COF).
View Article and Find Full Text PDFDespite improving soil quality and reducing nitrogen (N) loss in paddy soil, replacing chemical fertilizer with organic fertilizer would significantly accelerate greenhouse gas emission in terms of methane (CH). The application of slow-release fertilizer has been proposed an effective approach to control CH emissions, in addition to reducing N loss. Yet, the understanding of CH emissions from paddy fields with the additions of different fertilizers is still less known.
View Article and Find Full Text PDFSystemic health effects from exposure to a complex natural dust containing heavy metals from the Nellis Dunes Recreation Area (NDRA) near Las Vegas, NV, were evaluated. Several toxicological parameters were examined following lung exposure to emissive dust from three geologic sediment types heavily used for recreational off-road activities: yellow sand very rich in arsenic (termed CBN 5); a shallow cover of loose dune sand overlying a gravelly subsoil bordering dune fields (termed CBN 6); and brown claystone and siltstone (termed CBN 7). Adult female B6C3F1 mice were exposed by oropharyngeal administration to these three types of geogenic dusts at 0.
View Article and Find Full Text PDFThe specific health effects of direct inhalation of fine minerogenic dusts generated by natural soil surfaces remain poorly known and relatively little researched. To learn more about this exposure and its contribution to human health effects, we surveyed surface sediment and characterized dust from the Nellis Dunes Recreation Area (NDRA) in Clark County, Nevada, a popular off-road vehicle (ORV) recreational site. Dry drainage systems at NDRA are commonly used as natural trail systems for ORV recreation; these surfaces also are characterized by high concentrations of heavy metals.
View Article and Find Full Text PDFDesert areas are usually characterized by a continuous deposition of fine airborne particles. Over time, this process results in the accumulation of silt and clay on desert surfaces. We evaluated health effects associated with regional atmospheric dust, or geogenic dust, deposited on surfaces in the Nellis Dunes Recreation Area (NDRA) in Clark County, Nevada, a popular off-road vehicle (ORV) recreational site frequented daily by riders, families, and day campers.
View Article and Find Full Text PDFMaternal placentophagy has recently emerged as a rare but increasingly popular practice among women in industrialized countries who often ingest the placenta as a processed, encapsulated supplement, seeking its many purported postpartum health benefits. Little scientific research, however, has evaluated these claims, and concentrations of trace micronutrients/elements in encapsulated placenta have never been examined. Because the placenta retains beneficial micronutrients and potentially harmful toxic elements at parturition, we hypothesized that dehydrated placenta would contain detectable concentrations of these elements.
View Article and Find Full Text PDFGeogenic dust from arid environments is a possible inhalation hazard for humans, especially when using off-road vehicles that generate significant dust. This study focused on immunotoxicological and neurotoxicological effects following subacute exposure to geogenic dust generated from sediments in the Nellis Dunes Recreation Area near Las Vegas, Nevada that are particularly high in arsenic; the naturally-occurring arsenic concentrations in these surficial sediments ranged from 4.8 to 346μg/g.
View Article and Find Full Text PDFExposure to geogenic particulate matter (PM) comprised of mineral particles has been linked to human health effects. However, very little data exist on health effects associated with geogenic dust exposure in natural settings. Therefore, we characterized particulate matter size, metal chemistry, and health effects of dust collected from the Nellis Dunes Recreation Area (NDRA), a popular off-road vehicle area located near Las Vegas, NV.
View Article and Find Full Text PDFElevated concentrations of arsenic, up to 7058 μg g(-1) in topsoil and bedrock, and more than 0.03 μg m(-3) in air on a 2-week basis, were measured in the Nellis Dunes Recreation Area (NDRA), a very popular off-road area near Las Vegas, Nevada, USA. The elevated arsenic concentrations in the topsoil and bedrock are correlated to outcrops of yellow sandstone belonging to the Muddy Creek Formation (≈ 10 to 4 Ma) and to faults crossing the area.
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