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Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark B. Neely francis M. rouquette jr. Cristine L.S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha-1) and contributed the most total N (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea

关键词： Annual Legumes Soil N Soil Organic C Green Manure Deer Browse Forage Cropping Systems

Legume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark B. Neely francis M. rouquette jr. Cristine L. S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife Research Overton TX USA Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biomass sorghum production system to evaluate impacts on N concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total N and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and winter fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertilizer treatments (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CPGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. Rate of N fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil N over time indicated mineralization of organic N and may explain why no N fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum Legumes Green Manure Intercrop Cowpea Crimson Clover Soil Organic Carbon Soil Nitrogen

The El Niño-Southern Oscillation (ENSO) Effects on Cowpea and Winter Wheat Yields in the Semi-Arid Region of the Southern US

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Agricultural Sciences 2023年第2期14卷 154-175页

作者： Prem Woli Gerald R. Smith Charles R. Long francis M. rouquette jr. Texas A&M AgriLife Research Center Overton TX USA

Information is limited on the effects of climate variability on cowpea (Vigna unguiculata L.) and winter wheat (Triticum aestivum L.) yields in the semiarid region of the southern US. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data spanning 81 years, we assessed the impact of El Niño-Southern Oscillation (ENSO) on the grain yields of these crops in the Llano Estacado region of the southern US as affected by cowpea and wheat planting dates and N application rate. Simulated results showed that the El Niño phase of ENSO produced about 30% more yields of mono-cropped cowpea than those produced under the La Niña phase, especially with the cowpeas planted in July. The cowpea yields under El Niño were about 10% more than the 81-year average normal yield, whereas those under La Niña were about 20% less. At the N rates of 0, 50, and 100 kg·ha−1, regardless of wheat planting dates, the El Niño years produced, respectively, about 8%, 40%, and 60% higher wheat yields than those produced in the La Niña years, and about 5%, 20%, and 27% more than the 81-year average normal yield. In the La Niña years, the wheat yields at 0, 50, and 100 kg N ha−1 were, respectively, about 5%, 15%, and 20% less than the normal yield with similar N levels. The impact of ENSO on wheat yields under cowpea-wheat double-cropping systems was significant, especially for the wheat crops planted on October 15 (October 30) or later following the cowpea crops planted in June (July). At zero N, the mono-cropped wheat yields were not impacted by ENSO due to N limitation. However, the double-cropped wheat yields were impacted by ENSO even when no N fertilizer was applied due to high soil N status caused by N transfer from cowpea stover residues and roots. Results indicated that management strategies need to be attentive to ENSO forecasts and adjust potential planting dates and N application rates with the ENSO phase to avert risks of crop fa

关键词： Climate Cowpea DSSAT Double-Crop El Niño ENSO Model Semi-Arid Wheat

Exploring the Potential of Cowpea-Wheat Double Cropping in the Semi-Arid Region of the Southern United States Using the DSSAT Crop Model

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Agricultural Sciences 2023年第1期14卷 35-57页

作者： Prem Woli Gerald R. Smith Charles R. Long Jackie C. Rudd Qingwu Xue francis M. rouquette jr. Texas A&M AgriLife Research Center Overton USA Texas A&M AgriLife Research Center Amarillo USA

Information is limited on the potential of double-cropping cowpea (Vigna unguiculata L.) and wheat (Triticum aestivum L.) in the semiarid region of the southern United States. Using the Decision Support System for Agrotechnology Transfer (DSSAT) crop model and weather data of 80 years, we assessed the possibility of cowpea-wheat double-cropping in this region for grain purpose as affected by planting date and N application rate. Results showed that the possibility of double-cropping varied from 0% to 65%, depending on the cropping system. The possibility was less with systems comprising earlier planting dates of wheat and later planting dates of cowpea. Results indicated that cowpea-wheat double-cropping could be beneficial only when no N was applied, with wheat planted on October 15 or later. At zero N, the double-crops of cowpea planted on July 15 and wheat planted on November 30 were the most beneficial of all the 72 double-cropping systems studied. With a delay in planting cowpea, the percentage of beneficial double-cropping systems decreased. At N rates other than zero, fallow-wheat monocropping systems were more beneficial than cowpea-wheat double-cropping systems, and the benefit was greater at a higher N rate. At 100 kg N ha-1, the monocrop of wheat planted on October 15 was the most beneficial of all the 94 systems studied. Results further showed that fallow-wheat yields increased almost linearly with an increase in N rate from 0 to 100 kg∙ha-1. Fallow-wheat grain yields were quadratically associated with planting dates. With an increase in N rate, wheat yields reached the peak with an earlier planting date. Wheat yields produced under monocropping systems were greater than those produced under double-cropping systems for any cowpea planting date. Cowpea yields produced under monocropping systems were greater than those produced under any double-cropping system. The relationship between cowpea grain yields and planting dates was

关键词： Cover-Crop Cowpea-Wheat DSSAT Double-Crop Model Semi-Arid

Proactive reconciliation as a tool for integrating mining and milling operations

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International Journal of Mining Science and Technology 2019年第2期29卷 239-244页

作者： Ana Carolina Chieregati Luiz Eduardo Campos Pignatari francis Fernand Pitard Homero Delboni jr Department of Mining and Petroleum Engineering University of Sao Paulo EDEM Engenharia Mineral francis Pitard Sampling Consultants

Historically, reconciliation has been viewed as a quality test of model estimates as well as a powerful tool for detecting and correcting problems in all stages of mine operations from resource estimation to metal production. If used correctly, reconciliation helps to better predict the life of mine(LOM), improves the adherence of production plans to the respective budget, and allows for effective control of the mining and milling processes. However, the accuracy of reconciliation results requires that all input data must be generated in accordance with the principles of sampling correctness. Furthermore, complete reconciliation systems can become extremely complex and must be carefully analyzed in order to provide realistic and helpful conclusions. Based on these concepts, this paper presents a successful proactive reconciliation system applied to a copper and gold mine in Brazil for monitoring and integrating mining and milling operations.

关键词： Reconciliation Prognostication Sampling Gold Copper

An Adaptive Sequential Replacement Method for Variable Selection in Linear Regression Analysis

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Open Journal of Statistics 2023年第5期13卷 746-760页

作者： Jixiang Wu Johnie N. Jenkins Jack C. McCarty jr. Genetics and Sustainable Agriculture Research Unit USDA-ARS Mississippi State USA

With the rapid development of DNA technologies, high throughput genomic data have become a powerful leverage to locate desirable genetic loci associated with traits of importance in various crop species. However, current genetic association mapping analyses are focused on identifying individual QTLs. This study aimed to identify a set of QTLs or genetic markers, which can capture genetic variability for marker-assisted selection. Selecting a set with k loci that can maximize genetic variation out of high throughput genomic data is a challenging issue. In this study, we proposed an adaptive sequential replacement (ASR) method, which is considered a variant of the sequential replacement (SR) method. Through monte Carlo simulation and comparing with four other selection methods: exhaustive, SR method, forward, and backward methods we found that the ASR method sustains consistent and repeatable results comparable to the exhaustive method with much reduced computational intensity.

关键词： Adaptive Sequential Replacement Association Mapping Exhaustive Method Global Optimal Solution Sequential Replacement Variable Selection

The impact of the coronavirus disease 2019 pandemic on physical activity in U.S. children

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Journal of Sport and Health Science 2021年第3期10卷 323-332页

作者： Kirsten Tulchin-francis Wilshaw Stevens jr.Xiangli Gu Tao Zhang Heather Roberts Jean Keller Dana Dempsey Justine Borchard Kelly Jeans Jonathan VanPelt Division of Movement Science Research DepartmentScottish Rite for ChildrenDallasTX 75219USA Department of Health Care Sciences School of Health ProfessionsUniversity of Texas Southwestern Medical CenterDallasTX 75235USA Department of Kinesiology University of Texas at ArlingtonArlingtonTX 76019USA Departrment of Kinesiology Health Promotion and RecreationCollege of EducationUniversity of North TexasDentonTX 76201USA Department of Occupational Therapy Texas Woman’s UniversityDentonTX 76204USA Division of Clinical Research Research DepartmentScottish Rite for ChildrenDallasTX 75219USA Therapeutic Recreation Department Scottish Rite for ChildrenDallasTX 75219USA

Background:Daily moderate-to-vigorous physical activity(MVPA)is vital to the physical,mental,and social well-being of *** restrictions during the coronavirus disease 2019(COVID-19)pandemic included the closure of schools and physical activity(PA)amenities across the *** study aimed to examine the impact of the pandemic on the PA and play behavior of *** and to provide evidencebased recommendations to improve their ***:A cross-sectional,online,parent-reported survey was conducted of children aged 318 years between April and June 2020 to assess light PA and MVPA using a modified Godin Leisure-Time Exercise *** items included family/child socioeconomic demographics,child adaptability to the pandemic,and community *** survey was shared through social media and snowball sampling ***:Analysis of 1310 surveys indicated child PA scores declined significantly during the pandemic(from 56.6 to 44.6,max 119,p<0.001).Specifically,MVPA score decreased(from 46.7 to 34.7,max 98,p<0.001)while light PA remained the ***-based changes were seen in the quantity,variety,and intensity of PA,with the lowest pandemic-related impact seen in preschoolers and the highest in high schoolers(4.7 vs.17.2,p<0.001).Community-based peer PA decreased across all age ***:This study shows decreased PA levels in ***,according to parent reporting,during the COVID-19 *** for community leaders,educators,and parents to improve PA in children are *** continued spread of COVID-19,these results and recommendations may be imperative to the physical well-being of ***.

关键词： Adolescents COVID-19 Moderate-to-vigorous physical activity Pediatric Youth

A monte Carlo-Based Approach for Groundwater Chemistry Inverse Modeling

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Open Journal of Modern Hydrology 2014年第4期4卷 112-120页

作者： Walt W. McNab jr. Kennedy/Jenks Consultants San Francisco USA

Inverse geochemical modeling of groundwater entails identifying a set of geochemical reactions which can explain observed changes in water chemistry between two samples that are spatially related in some sense, such as two points along a flow pathway. A common inversion approach is to solve a set of simultaneous mass and electron balance equations involving water-rock and oxidation-reduction reactions that are consistent with the changes in concentrations of various aqueous components. However, this mass-balance approach does not test the thermodynamic favorability of the resulting model and provides limited insight into the model uncertainties. In this context, a monte Carlo-based forward-inverse modeling method is proposed that generates probability distributions for model parameters which best match the observed data using the Metro-polis-Hastings search strategy. The forward model is based on the well-vetted PHREEQC geochemical model. The proposed modeling approach is applied to two test applications, one involving an inverse modeling example supplied with the PHREEQC code that entails groundwater interactions with a granitic rock mineral assemblage, and the other concerning the impact of fuel hydrocarbon bioattenuation on groundwater chemistry. In both examples, the forward-inverse approach is able to approximately reproduce observed water quality changes invoking mass transfer reactions that are all thermodynamically favorable.

关键词： Inverse Model Geochemical Model monte Carlo Simulation

Single nucleotide polymorphism(SNP)in genes of lupus:A Philippine study(SIGLA-PH)

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Rheumatology & Autoimmunity 2022年第1期2卷 22-30页

作者： Michael L.Tee Cherica A.Tee Jose B.Nevado jr.Angeline Therese Santiago Aedrian A.Abrilla Carlo M.Lapid francis A.Tablizo Joshua A.Dizon El K.B.Morado Eva Maria Cutiongco-Dela Paz College of Medicine University of the Philippines ManilaManilaPhillipines Institute of Human Genetics National Institutes of HealthUniversity of the Philippines ManilaManilaPhillipines College of Medicine and Philippine General Hospital University of the Philippines ManilaManilaPhillipines Core Facility for Bioinformatics Philippine Genome CenterUniversity of the PhilippinesManilaPhillipines National Institutes of Health University of the Philippines ManilaManilaPhillipines

Background:Systemic lupus erythematosus(SLE)is a complex prototypic autoimmune disease,with a prevalence of 20–150 per 100,000,most commonly affecting women at child-bearing ***-wide association studies and fine mapping of candidate regions have paved the way for greater understanding of SLE as a disease of genetic–environmental susceptibility and the functions of the genes ***:This study was conducted to determine the association of selected single nucleotide polymorphisms(SNPs)from established genomic databases based on theoretical risk and protective odds ratios>2.5 or<0.40)to susceptibility of developing SLE among ***:We analyzed data from 310 SLE patients and 318 *** identified eight significant SNPs namely rs9271100,rs9271366,rs9272105,rs9275328,rs2647087,rs12734338,rs17885098,and rs3883013 to be associated with an increased risk of developing SLE among ***:Eight SNPs were found to be associated with the development of SLE among *** to previous genetic studies in lupus patients,majority of the SNPs were found in the major histocompatibilty complex genes in the HLA *** study identified two unique SNPs that will be validated as potential diagnostic markers for *** findings of this study may contribute to the development of a polygenic risk score in determining susceptibility to SLE among Filipinos.

关键词： genetics lupus SLE SNP susceptibility