A5044802268- Soil and Water Nutrient Dynamics
- Pharmaceutical and Antibiotic Environmental Impacts
- Soil Carbon and Nitrogen Dynamics
- Pesticide and Herbicide Environmental Studies
- Wastewater Treatment and Nitrogen Removal
- Hydrology and Watershed Management Studies
- Soil erosion and sediment transport
- Antibiotic Resistance in Bacteria
- Analytical chemistry methods development
- Weed Control and Herbicide Applications
- Pesticide Residue Analysis and Safety
- Fecal contamination and water quality
- Microbial Community Ecology and Physiology
- Water Treatment and Disinfection
- Soil Geostatistics and Mapping
- Plant Pathogens and Fungal Diseases
- Water Quality and Resources Studies
- Mycorrhizal Fungi and Plant Interactions
- Constructed Wetlands for Wastewater Treatment
- Plant Pathogens and Resistance
- Crop Yield and Soil Fertility
- Plant nutrient uptake and metabolism
- Plant Disease Resistance and Genetics
- Antibiotics Pharmacokinetics and Efficacy
- Gut microbiota and health
National Laboratory for Agriculture and the Environment
2015-2024
United States Department of Agriculture
1991-2022
Agricultural Research Service
2011-2022
Ames National Laboratory
2020
National Center for Agricultural Utilization Research
2017
Iowa State University
2001-2016
Grassland, Soil and Water Research Laboratory
2008
University of the Assumption
2007
Postnova Analytics (Germany)
2005
Purdue University West Lafayette
2004
Appropriate indicators for assessing soil quality on a regional scale using the National Resource Inventory (NRI) are unknown. Our objectives were to (i) identify factors present at scale, (ii) determine which vary significantly with land use, and (iii) select attributes within these that can be used as regional‐scale assessment. Ascalon (fine‐loamy, mixed, superactive, mesic Aridic Argiustoll) Amarillo thermic Paleustalf) soils sampled from statistically representative subset of NRI sample...
A comparison of a natural, undisturbed ecosystem, mid‐elevation sage community, with severely disturbed old roadbed through this community revealed that more than 99% the plant cover in natural was mycorrhizal (vesicular‐arbuscular), whereas less 1% area (roadbed) mycorrhizal. Examples nonmycorrhizal plants as primary successional species habitats are discussed. The importance maintaining or re‐establishing fungal component reclamation programs designed to produce stable ecosystems is emphasized.
Tillage intensity affects soil microbiological activity in many ways, often driven by changes organic C (SOC) content. The magnitude and direction of those changes, however, depends on inherent (e.g., type texture), experimental study duration sampling depth) agronomic factors cropping system crop residue management). This nationwide meta-analysis examines published effects chisel plowing (CP), no-tillage (NT), perennial systems (PER) relative to moldboard plow (MP) seven health indicators:...
ABSTRACT We examined the ability of a soil bacterium, Agrobacterium radiobacter J14a, to degrade herbicide atrazine under variety cultural conditions, and we used this bacterium increase biodegradation in soils from agricultural chemical distribution sites. J14a cells grown nitrogen-free medium with citrate sucrose as carbon sources mineralized 94% 50 μg [ 14 C-U- ring ]atrazine ml −1 72 h concurrent population size 7.9 × 10 5 5.0 7 . Under these conditions [ethyl- C]atrazine incorporated...
Nitrate in water from tile drained corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] fields the U.S. Midwest contributes to nitrate contamination of surface waters. Denitrification-based biofilters are a promising strategy for reducing concentrations, but these systems require an external carbon supply sustain denitrification. The ability four organic materials serve as substrates denitrification was evaluated this laboratory study. Wood chips, wood chips amended with oil, cornstalks,...
Populations of the endomycorrhizal fungus Glomus fasciculatus were significantly reduced following land disturbance in western Colorado soil. A bioassay was developed to measure changes population. In bioassay, inoculum levels measured by comparing percentage infection corn ( Zea mays ) root systems thirty days after planting undisturbed or disturbed soils. The 2% soil compared 77% adjacent identified as endophyte both Considering importance and function fungi their plant hosts reduction...
Woodchip denitrification bioreactors, a relatively new technology for edge-of-field treatment of subsurface agricultural drainage water, have shown potential nitrate removal. However, few studies evaluated the performance these reactors under varied controlled conditions including initial woodchip age and range hydraulic retention times (HRTs) temperatures similar to field. This study investigated (i) release total organic C (TOC) during reactor start up fresh weathered woodchips, (ii)...
Sustainable intensification is an emerging model for agriculture designed to reconcile accelerating global demand agricultural products with long-term environmental stewardship. Defined here as increasing production while maintaining or improving quality, sustainable hinges upon decision-making by producers, consumers, and policy-makers. The Long-Term Agroecosystem Research (LTAR) network was established inform these decisions. Here we introduce the LTAR Common Experiment, through which...
Abstract The concept of soil health has evolved over the past several decades, recognizing that dynamic property response to management and land use is highly dependent on site‐specific factors must be considered when interpreting measurements. Initially, Soil Management Assessment Framework (SMAF) Comprehensive Health (CASH) were developed used globally for scoring indicators. However, both SMAF CASH frameworks using a relatively small dataset their interpretation curves not validated at...
Agriculture in the United States must respond to escalating demands for productivity and efficiency, as well pressures improve its stewardship of natural resources. Growing global population changing diets, combined with a greater societal awareness agriculture's role delivering ecosystem services beyond food, feed, fiber, energy production, require comprehensive perspective on where how US agriculture can be sustainably intensified, that is, made more productive without exacerbating local...
Tillage intensity affects soil structure in many ways but the magnitude and type (+/−) of change depends on site-specific (e.g., type) experimental details (crop rotation, study length, sampling depth, etc.). This meta-analysis examines published effects chisel plowing (CP), no-tillage (NT) perennial cropping systems (PER) relative to moldboard (MP) three indicators: wet aggregate stability (AS), bulk density (BD) penetration resistance (PR). The data represents four depth increments (from 0...
Information on the probability distribution and variability of soil properties at a regional scale could improve ability USDA‐Natural Resources Conservation Service (NRCS) to monitor condition using National Inventory (NRI). Our objective was evaluate hypothesis that 17 physical, chemical, biological are: (i) normally distributed, or (ii) log‐normally distributed scale, estimate magnitude change may be detected assuming either normal log‐normal distribution. Samples were collected...
Watershed contamination from antibiotics is becoming a critical issue because of increased numbers confined animal‐feeding operations and the use in animal production. To understand fate tylosin manure before it land‐applied, degradation lagoon slurries at 22°C was studied. Tylosin disappearance followed biphasic pattern, where rapid initial loss by slow removal phase. The 90% times for tylosin, relomycin (tylosin D), desmycosin B) anaerobically incubated were 30 to 130 hours. Aerating...
A comparison of a natural, undisturbed ecosystem, mid-elevation sage community, with severely disturbed old roadbed through this community revealed that more than 99% the plant cover in natural was mycorrhizal (vesicular-arbuscular), whereas less 1% area (roadbed) mycorrhizal. Examples nonmycorrhizal plants as primary successional species habitats are discussed. The importance maintaining or re-establishing fungal component reclamation programs designed to produce stable ecosystems is emphasized.
Subsurface drainage in agricultural watersheds exports a large quantity of nitrate-nitrogen (NO(3)-N) and concentrations frequently exceed 10 mg L(-1). A laboratory column study was conducted to investigate the ability wood chip bioreactor promote denitrification under mean water flow rates 2.9, 6.6, 8.7 13.6 cm d(-1) which are representative flows entering subsurface tiles. Columns were packed with chips inoculated small amount oxidized till incubated at degrees C. Silicone sampling cells...
Imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine), a chloronicotinyl insecticide used to control biting and sucking insects, is very persistent in the soil with half-life often greater than 100 days. Although few metabolites have been reported literature, there are no reports of imidacloprid-degrading microorganisms. Our objectives were discover, isolate, characterize microorganisms capable degrading imidacloprid soil. Two soil-free stable enrichment cultures...
Populations of the endomycorrhizal fungus Glomus fasciculatus were significantly reduced following land disturbance in western Colorado soil. A bioassay was developed to measure changes population. In bioassay, inoculum levels measured by comparing percentage infection corn (Zea mays) root systems thirty days after planting undisturbed or disturbed soils. The 2% soil compared 77% adjacent identified as endophyte both Considering importance and function fungi their plant hosts reduction...
Experiments were established in a controlled-growth chamber and the field to evaluate effect of length time intervals between winter rye cover crop termination corn planting on seedling disease, growth, grain yield 2014 2015. Rye dates ranged from 25 days before (DBP) 2 after (DAP) 21 DBP 1 DAP controlled studies. Results similar both environments. In general, shorter increased disease reduced emergence, shoot following compared with planted 10 or more without rye. Incidence Pythium spp....