A5062338804- Crop Yield and Soil Fertility
- Soil Carbon and Nitrogen Dynamics
- Soil and Water Nutrient Dynamics
- Agronomic Practices and Intercropping Systems
- Plant nutrient uptake and metabolism
- Wastewater Treatment and Nitrogen Removal
- Agriculture, Soil, Plant Science
- Phosphorus and nutrient management
- Nitrogen and Sulfur Effects on Brassica
- Soil Geostatistics and Mapping
- Soybean genetics and cultivation
- Agricultural Science and Fertilization
- Potato Plant Research
- Legume Nitrogen Fixing Symbiosis
- Rice Cultivation and Yield Improvement
- Remote Sensing in Agriculture
- Soil Mechanics and Vehicle Dynamics
- Plant Micronutrient Interactions and Effects
- Irrigation Practices and Water Management
- Agricultural Economics and Policy
- Bioenergy crop production and management
- Nematode management and characterization studies
- Wheat and Barley Genetics and Pathology
- Banana Cultivation and Research
- Polymer-Based Agricultural Enhancements
Iowa State University
2016-2025
VA Boston Healthcare System
2016
Purdue University West Lafayette
2014
North Dakota State University
2014
University of Missouri–St. Louis
2014
University of Arizona
2003
Armstrong Atlantic State University
2001
Northwest University
2001
Community Catalyst
1992
Goodwin College
1990-1991
Labile, 'high-quality', plant litters are hypothesized to promote soil organic matter (SOM) stabilization in mineral fractions that physicochemically protected from rapid mineralization. However, the effect of litter quality on SOM is inconsistent. High-quality litters, characterized by high N concentrations, low C/N ratios, and phenol/lignin not consistently stabilized with greater efficiency than 'low-quality' concentrations. Here, we attempt resolve these inconsistent results developing a...
Core Ideas Nitrogen recommendations for individual corn fields are less accurate than desired. need improvement economic and environmental reasons. A review of fundamental concepts will improve understanding about N recommendations. Examination recommendation systems, tests, models fixation by the Haber–Bosch process has more doubled amount fixed on Earth, significantly influencing global cycle. Much this is made into fertilizer that used to produce nearly half world's food. Too much...
Nitrogen fertilization is critical to optimize short-term crop yield, but its long-term effect on soil organic C (SOC) uncertain. Here, we clarify the impact of N SOC in typical maize-based (Zea mays L.) Midwest U.S. cropping systems by accounting for site-to-site variability maize yield response fertilization. Within continuous and maize-soybean [Glycine max (L.) Merr.] at four Iowa locations, evaluated changes surface over 14 16 years across a range fertilizer rates empirically determined...
Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce losses and increase profits. We tested the ability Agricultural Production Systems sIMulator (APSIM) to simulate soybean (Glycine max yields, economic optimum rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous soybean-corn) five (0, 67, 134, 201, 268 kg ha-1) applied corn. Our objectives were to: a) quantify model accuracy before after...
Abstract Global maize production alters an enormous soil organic C ( SOC ) stock, ultimately affecting greenhouse gas concentrations and the capacity of agroecosystems to buffer climate variability. Inorganic N fertilizer is perhaps most important factor within maize‐based systems due its effects on crop residue mineralization. Using a continuous cropping system with 13 year gradient (0–269 kg ha −1 yr that created large range in inputs (3.60–9.94 Mg dry matter ), we provide first agronomic...
Nitrous oxide (N2O) emission from denitrification in agricultural soils often increases with N fertilizer and soil nitrate (NO3) concentrations. Overwintering cover crops cereal rotations can decrease NO3 concentrations may N2O emissions. However, mineralizable C availability be a more important control on than concentration fertilized soils, crop residue provides input. We measured the effect of winter rye (Secale cereale L.) emissions maize (Zea mays cropping system treated banded at three...
The ability of biogeochemical ecosystem models to represent agro-ecosystems depends on their correct integration with field observations. We report simultaneous calibration 67 DayCent model parameters using multiple observation types through inverse modeling the PEST parameter estimation software. Parameter reduced total sum weighted squared residuals by 56% and improved fit crop productivity, soil carbon, volumetric water content, temperature, N2O, NO3− compared default simulation. Inverse...
The possibility that N fertilizer increases soil organic matter (SOM) mineralization and, as a result, reduces SOM stocks has led to great debate about the long-term sustainability of maize-based agroecosystems well best method estimate use efficiency (FNUE). Much this is because synthetic can positively or negatively affect via several direct and indirect pathways. Here, we test series hypotheses determine direction, magnitude, mechanism effect on discuss implications for methods FNUE. We...
Enormous challenges were presented by the 2012 drought. Poor water availability and high temperatures resulted in significant stress during critical phases of corn (Zea mays L.) soybean (Glycine max development. These factors lead to management with insects, diseases, reduced nutrient uptake plants. The drought triggered soil changes, particularly conventional tillage systems, such as increased fracturing, crusting, deterioration structure aggregation. All this reinforced need for...
Winter rye (Secale cereale L.) cover crop (RCC) has potential to reduce NO3–N loss from corn (Zea mays and soybean [Glycine max (L.) Merr.] fields. However, RCC effects on annual productivity optimal N fertilization requirement are unclear. The objectives were evaluate yield response rate. Treatments no-RCC with six fertilizer rates (0–225 kg ha-1) applied in a no-till corn–soybean (CS) rotation at four Iowa sites 2009 through 2011. biomass uptake was low, maximum of 1280 dry matter (DM)...
• Sustainable agriculture is complex and includes multiple interdependent goals. Sound science innovation are the keys to sustainable agriculture, already delivering results. Greater investment needed in basics of agronomy, biotechnology, plant breeding ensure that farmers consumers everywhere benefit from technology. Farmers must receive support for implementing sustainability measures, especially light downward trend commodity prices.
Fertilizing maize at an optimum nitrogen rate is imperative to maximize productivity and sustainability. Using a combination of long-term (n = 379) short-term 176) experiments, we show that the economic for US production has increased by 2.7 kg N ha−1 yr−1 from 1991 2021 (1.2% per year) simultaneously with grain yields losses. By accounting societal cost estimates losses, estimate environmental rate, which also over time but lower than rate. Furthermore, provide evidence reducing rates could...
Nitrogen application can have a significant effect on soil carbon (C) pools, plant biomass production, and microbial C processing. The focus of this study was to investigate the short-term N fertilization CO(2) emission C. conducted from 2001 2003 at four field sites in Iowa representing major associations with corn (Zea mays L.)-soybean (Glycine max L. Merr.) rotation. experimental design randomized complete block replications rates (0, 90, 180, 225 kg ha(-1)). In year, season-long...
Determining specific N fertilization rates to achieve optimal return is difficult. Crop stress sensing uses the plant as an indicator of need and has potential improve management. However, for making rate decisions, a calibrated relationship between measured optimum required. Corn ( Zea mays L.) was determined with chlorophyll meter (CM) at 102 site‐years trials conducted from 1999–2005 corn following soybean [ Glycine max (L.) Merr.] (SC) continuous (CC). Normalizing CM readings relative...
The drought of 2012 provides a unique opportunity to evaluate the effects cover crop on soil moisture under relatively extreme conditions. objective this study was quantify potential differences in due presence rye (<i>Secale cerale</i> L.) corn (<i>Zea mays</i> L.)–soybean (<i>Glycine max</i> rotation at various locations Midwestern United States during 2012. Soil volumetric water content (θ) and storage (SWS) were monitored three sites Iowa Indiana. Daily measurements θ taken 10, 20, 40,...
Core Ideas A Machine Learning approach was innovatively used to predict corn EONR. Two features were created approximate hydrological conditions for modeling Soil hydrology found essential in successful in‐season Determination of N requirement ( Zea mays L.) is challenging due interactions genotype, environment, and management. learning (ML), with its predictive power tackle complex systems, may solve this barrier the development locally based recommendations. The objective study explore...
Abstract Determining which corn ( Zea mays L.) N fertilizer rate recommendation tools best predict crop need would be valuable for maximizing profits and minimizing environmental consequences. Simultaneous comparisons of multiple across various conditions have been limited. The objectives this research were to evaluate the performance publicly‐available diverse soil weather for: (i) prescribing rates planting split‐fertilizer applications, (ii) economic effects. Corn N‐response trials using...
Accurate nitrogen (N) diagnosis early in the growing season across diverse soil, weather, and management conditions is challenging. Strategies using multi-source data are hypothesized to perform significantly better than approaches crop sensing information alone. The objective of this study was evaluate, environments, potential for integrating genetic (e.g., comparative relative maturity degree units key developmental growth stages), environmental soil weather), seeding rate, irrigation,...
Abstract Winter cover crop performance metrics (i.e., vegetative biomass quantity and quality) affect ecosystem services provisions, but they vary widely due to differences in agronomic practices, soil properties, climate. Cereal rye (S ecale cereale ) is the most common winter United States its hardiness, low seed cost, high production. We compiled data on cereal metrics, properties across eastern half of States. The dataset includes a total 5,695 observations 208 site-years between...