A5073947803- Soil Carbon and Nitrogen Dynamics
- Soil and Water Nutrient Dynamics
- Crop Yield and Soil Fertility
- Plant nutrient uptake and metabolism
- Ecology and Vegetation Dynamics Studies
- Peatlands and Wetlands Ecology
- Rice Cultivation and Yield Improvement
- Analytical Chemistry and Sensors
- Rangeland and Wildlife Management
- Soil and Unsaturated Flow
- Electrochemical sensors and biosensors
- Climate change impacts on agriculture
- Fire effects on ecosystems
- Plant Water Relations and Carbon Dynamics
- Hydrology and Watershed Management Studies
- Genetics and Plant Breeding
- Bioenergy crop production and management
- Advanced biosensing and bioanalysis techniques
- Microbial Community Ecology and Physiology
- Soybean genetics and cultivation
- Legume Nitrogen Fixing Symbiosis
- Climate change and permafrost
- Plant and animal studies
- Agriculture Sustainability and Environmental Impact
- Soil Geostatistics and Mapping
Iowa State University
2016-2025
Texas Tech University
2019
Texas Tech University Health Sciences Center
2019
University of Rhode Island
2004-2011
Louisiana Department of Natural Resources
2004-2011
Pennsylvania State University
2009-2011
Arkansas Agricultural Experiment Station
2006-2007
Saint Louis University
2005-2007
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...
There are many environmental benefits to incorporating cover crops into crop rotations, such as their potential decrease soil erosion, reduce nitrate (NO<sub>3</sub>) leaching, and increase organic matter. Some of these impact other agroecosystem processes, greenhouse gas emissions. In particular, there is not a consensus in the literature regarding effect on nitrous oxide (N<sub>2</sub>O) Compared site-specific studies, meta-analysis can provide more general investigation effects....
Abstract We used the Agricultural Production Systems sIMulator (APSIM) to predict and explain maize soybean yields, phenology, soil water nitrogen (N) dynamics during growing season in Iowa, USA. Historical, current forecasted weather data were drive simulations, which released public four weeks after planting. In this paper, we (1) describe methodology perform forecasts; (2) evaluate model prediction accuracy against collected from 10 locations over years; (3) identify inputs that are key...
Dissolved organic matter (DOM) plays a vital role in biogeochemical processes and determining the responses of soil (SOM) to global change. Although quantity DOM has been inventoried across diverse spatio-temporal scales, underlying mechanisms accounting for variability dynamics remain unclear especially upland ecosystems. Here, gradient SOM storage 12 croplands northeast China was used understand links between dynamics, microbial metabolism, abiotic conditions. We assessed composition,...
Healthy soils contribute to a wide range of ecosystem services and virtually all the UN Sustainable Development Goals, but most world's soil resources are in only fair, poor, or very poor condition, conditions getting worse more cases than they improving. A total 33% moderately highly degraded as result erosion, loss organic matter, nutrient balance, salinization alkalinization, contamination, acidification, biodiversity, sealing, compaction, water status. Best management practices available...
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...
Abstract Anticipated increases in precipitation intensity due to climate change may affect hydrological controls on soil N 2 O fluxes, resulting a feedback between and greenhouse gas emissions. We evaluated hydrologic emissions during experimental water table fluctuations large, intact columns amended with 100 kg ha −1 KNO 3 ‐N. Soil were collected from three landscape positions that vary biogeochemical properties ( = 12 columns). flooded bottom surface simulate are typical for this site,...
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...
There is an unmet need for improved fertilizer management in agriculture. Continuous monitoring of soil nitrate would address this need. This paper reports all-solid-state miniature potentiometric sensor that works direct contact with soils to monitor nitrate-nitrogen (NO3--N) solution parts-per-million (ppm) resolution. A working electrode formed from a novel nanocomposite poly(3-octyl-thiophene) and molybdenum disulfide (POT-MoS2) coated on patterned Au covered nitrate-selective membrane...
Nitrogen (N) is an essential but generally limiting nutrient for biological systems. Development of the Haber-Bosch industrial process ammonia synthesis helped to relieve N limitation agricultural production, fueling Green Revolution and reducing hunger. However, massive use fertilizer has doubled moving through global cycle with dramatic environmental consequences that threaten planetary health. Thus, there urgent need reduce losses reactive from agriculture, while ensuring sufficient...
Quantifying historical changes in maize harvest index (HI), the fraction of above-ground biomass allocated to grain yield, can enhance our ability explain yield trends and estimate stover carbon inputs for sustainability assessments. However, HI genetic gain has not been primary focus previous era studies. The aim this study is knowledge gain. Our first objective quantify Bayer Crop Science Legacy hybrids investigate contribution breeding agronomic management. second develop a general-use...
Abstract Soil organic carbon (SOC) plays an essential role in mediating community structure and metabolic activities of belowground biota. Unraveling the evolution communities their feedback mechanisms on SOC dynamics helps embed ecology soil microbiome into cycling, which serves to improve biodiversity conservation management strategy under global change. Here, croplands with a gradient were used understand how metabolisms decomposition linked diversity, composition, co‐occurrence networks...