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- Author:
- Douglas R. Smith, et al. ; Kabindra Adhikari; Harold Collins; Richard L. Haney; June E. Wolfe; Show all 5 Authors
- Source:
- Ecological indicators 2021 v.125 pp. 107482
- ISSN:
- 1470-160X
- Subject:
- ammonium nitrogen; carbon dioxide; clay; corn; crop yield; drought; health status; nitrate nitrogen; organic carbon; organic nitrogen; rain; silty clay soils; soil depth; soil quality; total nitrogen; Texas
- Abstract:
- ... The phrase “soil health” describes the condition of a soil in terms of its physical, chemical, and biological properties. The relationship between soil health and crop yield is rather complex, and quantifying their spatial characteristics at field scale is often limited in the literature. To explore the significance and spatial characteristics of soil health and its indicators in crop production, ...
- DOI:
- 10.1016/j.ecolind.2021.107482
- https://doi.org/10.1016/j.ecolind.2021.107482
- Author:
- Douglas R. Smith, et al. ; Xiaoqian Zhang; Igor M. Lopes; Ji-Qin Ni; Yongping Yuan; Chi-Hua Huang; Indrajeet Chaubey; Shubiao Wu; Show all 8 Authors
- Source:
- Journal of cleaner production 2021 v.307 pp. 127271
- ISSN:
- 0959-6526
- Subject:
- ammonium nitrogen; anaerobic digestion; animals; calcium; copper; dairy manure; feedstocks; iron; magnesium; manganese; organic fertilizers; pH; potassium; sodium; total Kjeldahl nitrogen; total phosphorus; zinc
- Abstract:
- ... Few studies have investigated the performance of anaerobic digestion (AD) to convert animal and agro-industrial wastes to organic fertilizers over a long-term field conditions. This paper studied three large-scale mesophilic digesters (D1–D3) over two years for their effects on feedstocks, which were dairy manure for D1 and D2 and co-digestion mixed manure and agro-industrial wastes for D3. Hydrau ...
- DOI:
- 10.1016/j.jclepro.2021.127271
- https://doi.org/10.1016/j.jclepro.2021.127271
- Author:
- Douglas R. Smith, et al. ; Helen P. Jarvie; R. Daren Harmel; Rick L. Haney; Show all 4 Authors
- Source:
- Journal of environmental quality 2019 v.48 no.5 pp. 1543-1548
- ISSN:
- 0047-2425
- Subject:
- agricultural runoff; base flow; carbon; fertilizer application; fields; land use; mineral fertilizers; nitrogen; pastures; phosphorus; poultry manure; soil; soil nutrients; soil sampling; stoichiometry; water quality; watersheds; Texas
- Abstract:
- ... Agricultural runoff is an important contributor to water quality impairment. This study was conducted to evaluate the potential role of field-scale management on carbon (C), nitrogen (N), and phosphorus (P) stoichiometry in soils and runoff from agricultural fields. Cultivated and pasture fields at the Riesel watersheds in central Texas were used for this analysis, and nutrients were transformed t ...
- Handle:
- 10113/6718818
- DOI:
- 10.2134/jeq2018.09.0338
- https://doi.org/10.2134/jeq2018.09.0338
- Author:
- Douglas R. Smith, et al. ; Robert Daren Harmel; Rick L. Haney; Peter M. Allen; Show all 4 Authors
- Source:
- Hydrological processes 2019 v.33 no.18 pp. 2384-2393
- ISSN:
- 0885-6087
- Subject:
- Vertisols; land use; nitrogen; nutrient content; organic fertilizers; overland flow; pastures; phosphorus; pollution load; preferential flow; rain; rhizosphere; runoff; seepage; soil profiles; surface water; vadose zone; water quality; watersheds; Texas
- Abstract:
- ... Recent studies have highlighted the agronomic and environmental importance of phosphorus (P) movement through the soil profile. Thus, faced with challenges such as high‐profile cases of P enrichment of surface water, better understanding of nutrient movement through soil is needed to better manage agricultural fertilizers and manures and their contribution to water quality degradation. In particul ...
- DOI:
- 10.1002/hyp.13474
- https://doi.org/10.1002/hyp.13474
- Author:
- Douglas R. Smith, et al. ; Richard L. Haney; Elizabeth B. Haney; Michael J. White; Show all 4 Authors
- Source:
- Applied soil ecology 2018 v.125 pp. 297-300
- ISSN:
- 0929-1393
- Subject:
- arginine; automation; carbon; carbon dioxide; citric acid; cover crops; microbial communities; peas; soil; soil respiration; soil sampling; vegetation; winter
- Abstract:
- ... Soil samples were obtained from under actively growing Austrian winter peas and from 2 m away in a plot that had no winter peas or other legumes growing in its cover crop mix. Soils were treated with 5 carbon (C) compounds (oxalic, malic, citric, glycine and arginine) and a control (deionized water). Microbial response was measured using an automated soil respiration system (ASRS). The soil under ...
- Handle:
- 10113/6112597
- DOI:
- 10.1016/j.apsoil.2017.12.016
- https://doi.org/10.1016/j.apsoil.2017.12.016
- Author:
- Douglas R. Smith, et al. ; Richard L. Haney; Elizabeth B. Haney; R. Daren Harmel; Mike J. White; Show all 5 Authors
- Source:
- Applied soil ecology 2018 v.125 pp. 162-168
- ISSN:
- 0929-1393
- Subject:
- cost effectiveness; environmental quality; health status; human health; nitrogen; nutrient availability; organic acids and salts; pH; phosphorus; politics; potassium; soil analysis; soil organic matter; soil quality; soil respiration; soil texture
- Abstract:
- ... Soil health has traditionally been judged in terms of production; however, it recently has gained a wider focus with a global audience, as soil condition is becoming an environmental quality, human health, and political issue. A crucial initial step in evaluating soil health is properly assessing the condition of the soil. Currently most laboratory soil analyses treat soils as non-living, non-inte ...
- Handle:
- 10113/6112561
- DOI:
- 10.1016/j.apsoil.2017.07.035
- https://doi.org/10.1016/j.apsoil.2017.07.035
- Author:
- Douglas R. Smith, et al. ; Katrina A. Macintosh; Donnacha G. Doody; Paul J.A. Withers; Richard W. McDowell; Laura T. Johnson; Tom W. Bruulsema; Vincent O'Flaherty; John W. McGrath; Show all 9 Authors
- Source:
- Science of the total environment 2019 v.649 pp. 90-98
- ISSN:
- 0048-9697
- Subject:
- crop yield; ecosystem services; farmers; issues and policy; landscapes; models; phosphorus; soil; stakeholders
- Abstract:
- ... Despite greater emphasis on holistic phosphorus (P) management, current nutrient advice delivered at farm-scale still focuses almost exclusively on agricultural production. This limits our ability to address national and international strategies for the delivery of multiple ecosystem services (ES). Currently there is no operational framework in place to manage P fertility for multiple ES delivery ...
- Handle:
- 10113/6114634
- DOI:
- 10.1016/j.scitotenv.2018.08.272
- https://doi.org/10.1016/j.scitotenv.2018.08.272
- Author:
- Douglas R. Smith, et al. ; Haw Yen; Jaehak Jeong; Show all 3 Authors
- Source:
- JAWRA Journal of the American Water Resources Association 2016 v.52 no.2 pp. 443-455
- ISSN:
- 1093-474X
- Subject:
- Soil and Water Assessment Tool model; agricultural watersheds; algorithms; calibration; guidelines; normal distribution; prediction; sampling; simulation models; variance; water quality; Texas
- Abstract:
- ... The primary advantage of Dynamically Dimensioned Search algorithm (DDS) is that it outperforms many other optimization techniques in both convergence speed and the ability in searching for parameter sets that satisfy statistical guidelines while requiring only one algorithm parameter (perturbation factor) in the optimization process. Conventionally, a default value of 0.2 is used as perturbation f ...
- Handle:
- 10113/62883
- DOI:
- 10.1111/1752-1688.12394
- CHORUS:
- 10.1111/1752-1688.12394
- https://doi.org/10.1111/1752-1688.12394
- Author:
- Douglas R. Smith, et al. ; Mark R. Williams; Stanley J. Livingston; Chad J. Penn; Kevin W. King; Chi-hua Huang; Show all 6 Authors
- Source:
- Journal of hydrology 2018 v.559 pp. 749-761
- ISSN:
- 0022-1694
- Subject:
- agricultural watersheds; algal blooms; basins; conservation practices; drainage; drainage systems; environmental factors; eutrophication; factor analysis; highlands; hysteresis; landscapes; nitrate nitrogen; nutrient availability; nutrient management; nutrient transport; phosphorus; poorly drained soils; prediction; storms; streams; surface water; Lake Erie; Midwestern United States
- Abstract:
- ... Understanding the processes controlling nutrient delivery in headwater agricultural watersheds is essential for predicting and mitigating eutrophication and harmful algal blooms in receiving surface waters. The objective of this study was to elucidate nutrient transport pathways and examine key components driving nutrient delivery processes during storm events in four nested agricultural watershed ...
- DOI:
- 10.1016/j.jhydrol.2018.02.079
- https://doi.org/10.1016/j.jhydrol.2018.02.079
- Author:
- Douglas R. Smith, et al. ; Richard L. Haney; Elizabeth B. Haney; Michael J. White; Show all 4 Authors
- Source:
- Open journal of soil science 2017 v.7 no.11 pp. 301-314
- ISSN:
- 2162-5360
- Subject:
- aluminum; ammonium nitrogen; calcium; citrates; iron; lithium; nitrate nitrogen; nutrient availability; phosphorus; potassium; root exudates; soil analysis; soil nutrients; soil pH; soil quality
- Abstract:
- ... The soil extractant, H3A, has undergone several iterations to extract calcium (Ca), iron (Fe), aluminum (Al), potassium (K), phosphorus (P), ammonium (NH4-N) and nitrate (NO3-N) under ambient soil conditions. Few soil extractants currently used by commercial and university soil testing laboratories can perform multi-nutrient extraction without over- or under-estimating at least one nutrient. Soil ...
- Handle:
- 10113/6764830
- DOI:
- 10.4236/ojss.2017.711022
- https://doi.org/10.4236/ojss.2017.711022
- Author:
- Douglas R. Smith, et al. ; Elizabeth A. Warnemuende-Pappas; Show all 2 Author
- Source:
- Soil & tillage research 2015 v.153 pp. 155-160
- ISSN:
- 0167-1987
- Subject:
- Glycine max; Zea mays; agricultural runoff; agricultural watersheds; ammonium nitrogen; atrazine; conservation practices; conventional tillage; corn; crop rotation; herbicide residues; losses from soil; nitrate nitrogen; no-tillage; nonpoint source pollution; nutrients; phosphorus; pollution load; rainfall simulation; risk; sediment yield; sediments; soybeans; surface water; water quality
- Abstract:
- ... Increasing soluble phosphorus (SP) loads to Lake Erie occurring around the same time as the implementation of no-tillage in the watershed has led to speculation that this important conservation practice is a primary cause of the SP loading. Thus, conservationists are interested in finding management practices that will minimize stratification of P, which may be common in no-tillage systems, while ...
- Handle:
- 10113/61155
- DOI:
- 10.1016/j.still.2015.04.004
- https://doi.org/10.1016/j.still.2015.04.004
- Author:
- Douglas R. Smith, et al. ; Martha R. Zwonitzer; Michelle L. Soupir; Laura R. Jarboe; Show all 4 Authors
- Source:
- Journal of environmental quality 2016 v.45 no.2 pp. 609-617
- ISSN:
- 0047-2425
- Subject:
- Escherichia coli; adhesion; amoxicillin; antibiotic resistance; bacteria; chlortetracycline; conventional farming; erythromycin; farms; humans; kanamycin; land application; minimum inhibitory concentration; neomycin; organic foods; organic production; overland flow; pig manure; quantitative analysis; sand; silica; soil; statistical analysis; streptomycin; swine; tetracycline; tylosin
- Abstract:
- ... Broad-spectrum antibiotics are often administered to swine, contributing to the occurrence of antibiotic-resistant bacteria in their manure. During land application, the bacteria in swine manure preferentially attach to particles in the soil, affecting their transport in overland flow. However, a quantitative understanding of these attachment mechanisms is lacking, and their relationship to antibi ...
- Handle:
- 10113/62922
- DOI:
- 10.2134/jeq2015.05.0245
- https://doi.org/10.2134/jeq2015.05.0245
- Author:
- Douglas R. Smith, et al. ; Kevin W. King; Mark R. Williams; Laura T. Johnson; Gregory A. LaBarge; Norman R. Fausey; Show all 6 Authors
- Source:
- Journal of environmental quality 2017 v.46 no.2 pp. 466-469
- ISSN:
- 0047-2425
- Subject:
- algal blooms; basins; drainage water; fertilizer application; nitrates; phosphorus fertilizers; pollution load; rain; reactive phosphorus; soil; soil analysis; Lake Erie
- Abstract:
- ... The Western Lake Erie Basin (WLEB) was inundated with precipitation during June and July 2015 (two to three times greater than historical averages), which led to significant nutrient loading and the largest in-lake algal bloom on record. Using discharge and concentration data from three spatial scales (0.18–16,000 km²), we contrast the patterns in nitrate (NO₃–N) and dissolved reactive phosphorus ...
- Handle:
- 10113/5927831
- DOI:
- 10.2134/jeq2016.11.0434
- https://doi.org/10.2134/jeq2016.11.0434
- Author:
- Douglas R. Smith, et al. ; Kevin W. King; Mark R. Williams; Show all 3 Authors
- Source:
- Journal of soil and water conservation 2015 v.70 no.2 pp. 27A-29A
- ISSN:
- 0022-4561
- Subject:
- Dreissena polymorpha; agricultural watersheds; algal blooms; animal manures; bioavailability; climate change; commodity prices; cropping systems; crops; ethanol production; farm management; farm size; fertilizer rates; glyphosate; herbicide resistance; lakes; losses from soil; nitrogen; no-tillage; nonpoint source pollution; nutrient use efficiency; on-farm research; phosphorus; phosphorus fertilizers; pollution load; soil analysis; soil biology; soil fertility; soil nutrients; soil pH; tile drainage; transgenic plants; water pollution; Lake Erie
- Abstract:
- ... Harmful and nuisance algal blooms have been increasing in size and extent since about 2000. In recent years, the release of the algal toxin microcystin has become a growing concern and has resulted in the inability to use water from Lake Erie as a drinking water source to the 400,000 residents of Toledo, Ohio in August, 2014. Farmers in the Western Lake Erie Basin have received the brunt of the bl ...
- Handle:
- 10113/60955
- DOI:
- 10.2489/jswc.70.2.27A
- https://doi.org/10.2489/jswc.70.2.27A
- Author:
- Douglas R. Smith, et al. ; Javier M. Gonzalez; Stan Livingston; Elizabeth Warnemuende-Pappas; Martha Zwonitzer; Show all 5 Authors
- Source:
- Journal of soils and sediments 2016 v.16 no.7 pp. 1921-1932
- ISSN:
- 1439-0108
- Subject:
- 2,4-D; atrazine; conservation practices; farms; glyphosate; metolachlor; pollutants; runoff; soil; Midwestern United States
- Abstract:
- ... PURPOSE: In a 6-year study, we investigated the effectiveness of blind inlets as a conservation practice in reducing pesticide losses compared to tile risers from two closed farmed depressional areas (potholes) in the US Midwest under a 4-year cropping rotation. MATERIALS AND METHODS: In two adjacent potholes within the same farm and having similar soils, a conventional tile riser and blind inlet ...
- DOI:
- 10.1007/s11368-016-1362-0
- https://doi.org/10.1007/s11368-016-1362-0
- Author:
- Douglas R. Smith, et al. ; Emily W. DUNCAN; Mark R. WILLIAMS; Greg LABARGE; Lindsay A. PEASE; Norman R. FAUSEY; Kevin W. King; Show all 7 Authors
- ISSN:
- 2471-9625
- Subject:
- agricultural runoff; agricultural soils; fertilizer application; highlands; losses from soil; nutrient content; phosphorus; phosphorus fertilizers; pollution load; regression analysis; risk; screening; water quality; Ohio
- Abstract:
- ... Harmful and nuisance algal blooms resulting from excess phosphorus (P) have placed agriculture in the spotlight of the water quality debate. Sixty-eight site years of P loading data (combined surface runoff and tile flow) from 36 fields in Ohio were used to see if a soil test P (STP) concentration could be identified that allowed P application while still meeting recommended loss thresholds. Regre ...
- Handle:
- 10113/5801831
- DOI:
- 10.2134/ael2017.02.0004.
- https://doi.org/10.2134/ael2017.02.0004.
17. Increased Soluble Phosphorus Loads to Lake Erie: Unintended Consequences of Conservation Practices?
- Author:
- Douglas R. Smith, et al. ; Helen P. Jarvie; Laura T. Johnson; Andrew N. Sharpley; David B. Baker; Tom W. Bruulsema; Remegio Confesor; Show all 7 Authors
- Source:
- Journal of environmental quality 2017 v.46 no.1 pp. 123-132
- ISSN:
- 0047-2425
- Subject:
- atmospheric precipitation; basins; conservation practices; eutrophication; land management; losses from soil; phosphorus; pollution load; profitability; reduced tillage; regression analysis; rivers; runoff; soil; soil erosion; subsurface drainage; tile drainage; time series analysis; watersheds; Lake Erie
- Abstract:
- ... Cumulative daily load time series show that the early 2000s marked a step-change increase in riverine soluble reactive phosphorus (SRP) loads entering the Western Lake Erie Basin from three major tributaries: the Maumee, Sandusky, and Raisin Rivers. These elevated SRP loads have been sustained over the last 12 yr. Empirical regression models were used to estimate the contributions from (i) increas ...
- Handle:
- 10113/5852146
- DOI:
- 10.2134/jeq2016.07.0248
- https://doi.org/10.2134/jeq2016.07.0248
- Author:
- Douglas R. Smith, et al. ; Helen P. Jarvie; Lisa R. Norton; Francois K. Edwards; Michael J. Bowes; Stephen M. King; Peter Scarlett; Sian Davies; Rachael M. Dils; Nuria Bachiller-Jareno; Show all 10 Authors
- Source:
- Science of the total environment 2018 v.621 pp. 849-862
- ISSN:
- 0048-9697
- Subject:
- carbon; compliance; data collection; eutrophication; hydrology; land use; monitoring; nitrogen; nitrogen content; nutrient content; nutrients; phosphorus; primary productivity; prioritization; remediation; risk; rivers; stoichiometry; streams; surveys; water quality; watersheds; Great Britain
- Abstract:
- ... This study provides a first national-scale assessment of the nutrient status of British headwater streams within the wider river network, by joint analysis of the national Countryside Survey Headwater Stream and Harmonised River Monitoring Scheme datasets. We apply a novel Nutrient Limitation Assessment methodology to explore the extent to which nutrients may potentially limit primary production i ...
- Handle:
- 10113/5979355
- DOI:
- 10.1016/j.scitotenv.2017.11.128
- https://doi.org/10.1016/j.scitotenv.2017.11.128
- Author:
- Douglas R. Smith, et al. ; Richard L. Haney; Elizabeth B. Haney; R. Daren Harmel; Mike J. White; Show all 5 Authors
- Source:
- Open journal of soil science 2016 v.06 no.11 pp. 175-187
- ISSN:
- 2162-5360
- Subject:
- agricultural soils; buffering capacity; crop production; eutrophication; fertilizers; nutrient availability; phosphorus; plant growth; root exudates; runoff; soil analysis; soil pH; statistical analysis; water quality; United States
- Abstract:
- ... Phosphorus is an essential nutrient for plant growth but in excess is a source of environmental pollution. Fertilizer additions of P are recommended based on soil tests; however, the commonly applied P extractants are often applied outside of their design criteria (specifically soil pH). As a result, soil tests can produce inaccurate estimates of plant available P in the soil, which either increas ...
- Handle:
- 10113/63336
- DOI:
- 10.4236/ojss.2016.611017
- https://doi.org/10.4236/ojss.2016.611017
- Author:
- Douglas R. Smith, et al. ; Haw Yen; Michael J. White; James C. Ascough II; Jeffrey G. Arnold; Show all 5 Authors
- Source:
- Journal of the American Water Resources Association 2016 v.52 no.3 pp. 788-798
- ISSN:
- 1752-1688
- Subject:
- calibration; case studies; denitrification; hydrologic models; nitrates; pollution load; sediment yield; simulation models; stream flow; subsurface flow; uncertainty analysis; watersheds
- Abstract:
- ... Watershed simulation models can be calibrated using “hard data” such as temporal streamflow observations; however, users may find upon examination of detailed outputs that some of the calibrated models may not reflect summative actual watershed behavior. Thus, it is necessary to use “soft data” (i.e., qualitative knowledge such as anticipated denitrification rates, that doesn’t have temporal measu ...
- Handle:
- 10113/62938
- DOI:
- 10.1111/1752-1688.12428
- https://doi.org/10.1111/1752-1688.12428
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