Agricultural Science Commons^™

Isolation And Analysis Of Microbial Communities In Soil, Rhizosphere, And Roots In Perennial Grass Experiments, Morgan R. Mcpherson, Peng Wang, Robert B. Mitchell, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Plant and soil microbiome studies are becoming increasingly important for understanding the roles microorganisms play in agricultural productivity. The purpose of this manuscript is to provide detail on how to rapidly sample soil, rhizosphere, and endosphere of replicated field trials and analyze changes that may occur in the microbial communities due to sample type, treatment, and plant genotype. The experiment used to demonstrate these methods consists of replicated field plots containing two, pure, warm-season grasses (Panicum virgatum and Andropogon gerardii) and a low-diversity grass mixture (A. gerardii, Sorghastrum nutans, and Bouteloua curtipendula). Briefly, plants …

Climate Change Challenges Require Collaborative Research To Drive Agrifood System Transformation, Gabrielle E. Roesch-Mcnally, Andrea D. Basche, Rebecca Schewe

Department of Agronomy and Horticulture: Faculty Publications

The recent Climate Science Special Report released as part of the Fourth National Climate Assessment confirms that we are living through the warmest period in modern civilization and that human activities are the primary driver of this warming (Wuebbles et al., 2017). These climatic changes have and will continue to impact global agricultural production, with food security and production consequences that will be felt unequally across the planet. Agricultural activities contribute to global warming emissions, while also offering opportunities for greenhouse gas mitigation. It is clear that the agrifood system will have to adapt to a changing climate. To better …

Hunger In The Land Of Plenty: Local Responses To Food Insecurity In Iowa, Gabrielle E. Roesch-Mcnally, Jacqueline Ann Nester, Andrea D. Basche, Eric Christianson, Emily Zimmerman

Department of Agronomy and Horticulture: Faculty Publications

Story County (estimated population 92,406 in 2013) lies in the heart of central Iowa, a state renowned for its remarkable agricultural productivity. Iowa leads all states for production of corn, soybean, and hogs. Revenues from agricultural products in Iowa total more than $30 billion annually according the 2012 Agricultural Census (USDA-NASS 2014). This productivity stems from a favorable natural and political environment. The temperate climate, productive soils, and gentle topography are ideal for our production system of commodity agriculture facilitated by federal policies, which include subsidized crop insurance and commodity payments (Horrigan, Lawrence, and Walker 2002). Despite this productivity and …

Strawberry Cultivars Vary In Productivity, Sugars And Phytonutrient Content When Grown In A Greenhouse During The Winter, Ellen T. Paparozzi, George Meyer, Vicki Schlegel, Erin Blankenship, Stacy A. Adams, M. Elizabeth Conley, Benjamin A. Loseke, Paul Read

Department of Agronomy and Horticulture: Faculty Publications

In many areas of the US, fresh locally grown berries are not available during the winter. With this in mind, a research study comprised of three experiments was conducted focused on cultivar selection for berry yield, number, sweetness and phytonutrient content. Using a capillary mat system with under bench heating within a double-layer polyethylene greenhouse, strawberries were grown in the Great Plains Region of the US during the winter. During experiment 1, 12 cultivars were grown; berries were weighed, counted and analyzed for sugars and phytonutrients. “Albion” plants produced a high number/mass of berries, had relatively high sugar content but …

Empirical Comparisons Of Different Statistical Models To Identify And Validate Kernel Row Number-Associated Variants From Structured Multi-Parent Mapping Populations Of Maize, Jinliang Yang, Cheng-Ting Yeh, Raghuprakash Kastoori Ramamurthy, Xinshuai Qi, Rohan L. Fernando, Jack C. M. Dekkers, Dorian J. Garrick, Dan Nettleton, Patrick Schnable

Department of Agronomy and Horticulture: Faculty Publications

Advances in next generation sequencing technologies and statistical approaches enable genomewide dissection of phenotypic traits via genome-wide association studies (GWAS). Although multiple statistical approaches for conducting GWAS are available, the power and cross-validation rates of many approaches have been mostly tested using simulated data. Empirical comparisons of single variant (SV) and multi-variant (MV) GWAS approaches have not been conducted to test if a single approach or a combination of SV and MV is effective, through identification and cross-validation of trait-associated loci. In this study, kernel row number (KRN) data were collected from a set of 6,230 entries derived from the …

A Novel Lidar-Based Instrument For High-Throughput, 3d Measurement Of Morphological Traits In Maize And Sorghum, Suresh Thapa, Feiyu Zhu, Harkamal Walia, Hongfeng Yu, Yufeng Ge

Department of Agronomy and Horticulture: Faculty Publications

Recently, imaged-based approaches have developed rapidly for high-throughput plant phenotyping (HTPP). Imaging reduces a 3D plant into 2D images, which makes the retrieval of plant morphological traits challenging. We developed a novel LiDAR-based phenotyping instrument to generate 3D point clouds of single plants. The instrument combined a LiDAR scanner with a precision rotation stage on which an individual plant was placed. A LabVIEW program was developed to control the scanning and rotation motion, synchronize the measurements from both devices, and capture a 360^◦ view point cloud. A data processing pipeline was developed for noise removal, voxelization, triangulation, and plant …

Linked Read Technology For Assembling Large Complex And Polyploid Genomes, Alina Ott, James C. Schnable, Cheng-Ting Yeh, Linjiang Wu, Chao Liu, Heng-Cheng Hu, Clifton L. Dalgard, Soumik Sarkar, Patrick Schnable

Department of Agronomy and Horticulture: Faculty Publications

Background: Short read DNA sequencing technologies have revolutionized genome assembly by providing high accuracy and throughput data at low cost. But it remains challenging to assemble short read data, particularly for large, complex and polyploid genomes. The linked read strategy has the potential to enhance the value of short reads for genome assembly because all reads originating from a single long molecule of DNA share a common barcode. However, the majority of studies to date that have employed linked reads were focused on human haplotype phasing and genome assembly.

Results: Here we describe a de novo maize B73 genome assembly …

Increasing Predictive Ability By Modeling Interactions Between Environments, Genotype And Canopy Coverage Image Data For Soybeans, Diego Jarquin, Reka Howard, Alencar Xavier, Sruti Das Choudhury

Department of Agronomy and Horticulture: Faculty Publications

Phenomics is a new area that offers numerous opportunities for its applicability in plant breeding. One possibility is to exploit this type of information obtained from early stages of the growing season by combining it with genomic data. This opens an avenue that can be capitalized by improving the predictive ability of the common prediction models used for genomic prediction. Imagery (canopy coverage) data recorded between days 14–71 using two collection methods (ground information in 2013 and 2014; aerial information in 2014 and 2015) on a soybean nested association mapping population (SoyNAM) was used to calibrate the prediction models together …

Long-Term Winter Wheat (Triticum Aestivum L.) Seasonal Irrigation Amount, Evapotranspiration, Yield, And Water Productivity Under Semiarid Climate, Koffi Djaman, Michael O'Neill, Curtis K. Owen, Daniel Smeal, Margaret West, Dallen Begay, Samuel Allen, Komlan Koudahe, Suat Irmak, Kevin Lombard

Department of Agronomy and Horticulture: Faculty Publications

A long-term field experiment was conducted from 2002 to 2014 for the evaluation of yield and water productivity of three winter wheat varieties—Kharkof, Scout 66, and TAM107—under sprinkler irrigation at New Mexico State University Agricultural Science Center at Farmington, NM. Winter wheat daily evapotranspiration was estimated following the United Nations Food and Agriculture Organization FAO crop coefficient approach (ETc = Kc ETo), and crop water use efficiency (CWUE), evapotranspiration water use efficiency (ETWUE), and irrigation water use efficiency (IWUE) were estimated for each growing season. There was inter-annual variation in seasonal precipitation and irrigation amounts. Seasonal irrigation amounts varied from …

Engineering Linear, Branched-Chain Triterpene Metabolism In Monocots, Chase Kempinski, Zuodong Jiang, Garrett Zinck, Shirley J. Sato, Zhengxiang Ge, Thomas E. Clemente, Joe Chappell

Department of Agronomy and Horticulture: Faculty Publications

Triterpenes are thirty-carbon compounds derived from the universal five-carbon prenyl precursors isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Normally, triterpenes are synthesized via the mevalonate (MVA) pathway operating in the cytoplasm of eukaryotes where DMAPP is condensed with two IPPs to yield farnesyl diphosphate (FPP), catalyzed by FPP synthase (FPS). Squalene synthase (SQS) condenses two molecules of FPP to generate the symmetrical product squalene, the first committed precursor to sterols and most other triterpenes. In the green algae Botryococcus braunii, two FPP molecules can also be condensed in an asymmetric manner yielding the more highly branched triterpene, botryococcene. Botryococcene …

Genetic Architecture Of Common Bunt Resistance In Winter Wheat Using Genome-Wide Association Study, Amira M. I. Mourad, Ahmed Sallam, Vikas Belamkar, Ezzat Mahdy, Bahy Bakheit, Atif Abo El-Wafaa, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Background: Common bunt (caused by Tilletia caries and T. foetida) has been considered as a major disease in wheat (Triticum aestivum) following rust (Puccinia spp.) in the Near East and is economically important in the Great Plains, USA. Despite the fact that it can be easily controlled using seed treatment with fungicides, fungicides often cannot or may not be used in organic and low-input fields. Planting common bunt resistant genotypes is an alternative.

Results: To identify resistance genes for Nebraska common bunt race, the global set of differential lines were inoculated. Nine differential lines carrying nine …

Cc-Type Glutaredoxins Mediate Plant Response And Signaling Under Nitrate Starvation In Arabidopsis, Ji-Yul Jung, Ji Hoon Ahn, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Background: Nitrogen is an essential nutrient in plants. Despite the importance of nitrogen for plant growth and agricultural productivity, signal transduction pathways in response to nitrate starvation have not been fully elucidated in plants.

Results: Gene expression analysis and ectopic expression were used to discover that many CC-type glutaredoxins (ROXYs) are differentially expressed in response to nitrate deprivation. A gain-of-function approach showed that ROXYs may play a role in nutrient sensing through the regulation of chlorophyll content, root hair growth, and transcription of nitrate-related genes such as NRT2.1 under low or high nitrate conditions. Reactive oxygen species (ROS) …

Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza

Department of Agronomy and Horticulture: Faculty Publications

The anticipated world population growth emphasizes a need to produce more food on less land. Cutting-edge technologies, including genetic engineering, can help to develop improved crop varieties and protect natural resources. In spite of the potential for genetically-modified (GM) crops to make crop production more efficient, they remain a polarizing issue due to safety concerns. This paper provides an overview of the risk assessment process. The safety of Bacillus thuringiensis (Bt) proteins is used as an example for how risk assessment is applied to GM crops. Risks associated with GM crops have proven to be low to non-existent. Developing countries …

Root And Shoot Contribution To Carbon And Nitrogen Inputs In The Topsoil Layer In No-Tillage Crop Systems Under Subtropical Conditions, Marciel Redin, Sylvie Recous, Celso Aita, Bruno Chaves, Ismael Cristiano Pfeifer, Leonardo Mendes Bastos, Getulio Elias Pilecco, Sandro Jose Giacomini

Department of Agronomy and Horticulture: Faculty Publications

Recycling of carbon (C) and nitrogen (N) from plants into soils is decisive for maintaining soil organic matter and soil fertility. Therefore, we quantified plant biomass and C and N in the shoots and roots from the topsoil layer for a wide range of annual crops grown under subtropical conditions. We grew 26 species, 13 main crops, and 13 cover crops, in the field in standard sowing arrangements. Root biomass was recovered from the 0.00-0.20 m soil layer at flowering, and shoot biomass was measured at flowering for all crops and at maturity only for the main crops. Root dry …

Genotype Imputation In Winter Wheat Using First-Generation Haplotype Map Snps Improves Genome-Wide Association Mapping And Genomic Prediction Of Traits, Moses Nyine, Shichen Wang, Kian Kiani, Katherine Jordan, Shuyu Liu, Patrick Byrne, Scott Haley, Stephen Baenziger, Shiaoman Chao, Robert Bowden, Eduard Akhunov

Department of Agronomy and Horticulture: Faculty Publications

Genome-wide single nucleotide polymorphism (SNP) variation allows for the capture of haplotype structure in populations and prediction of unobserved genotypes based on inferred regions of identity-by-descent (IBD). Here we have used a first-generation wheat haplotype map created by targeted re-sequencing of low-copy genomic regions in the reference panel of 62 lines to impute marker genotypes in a diverse panel of winter wheat cultivars from the U.S. Great Plains. The IBD segments between the reference population and winter wheat cultivars were identified based on SNP genotyped using the 90K iSelect wheat array and genotyping by sequencing (GBS). A genome-wide association study …

Genome-Wide Association Study Reveals Novel Genomic Regions Associated With 10 Grain Minerals In Synthetic Hexaploid Wheat, Madhav Bhatta, P. Stephen Baenziger, Brian M. Waters, Rachana Poudel, Vikas Belamkar, Jesse Poland, Alexey Morgounov

Department of Agronomy and Horticulture: Faculty Publications

Synthetic hexaploid wheat (SHW; Triticum durum L. x Aegilops tauschii Coss.) is a means of introducing novel genes/genomic regions into bread wheat (T. aestivum L.) and a potential genetic resource for improving grain mineral concentrations. We quantified 10 grain minerals (Ca, Cd, Cu, Co, Fe, Li, Mg, Mn, Ni, and Zn) using an inductively coupled mass spectrometer in 123 SHWs for a genome-wide association study (GWAS). A GWAS with 35,648 single nucleotide polymorphism (SNP) markers identified 92 marker-trait associations (MTAs), of which 60 were novel and 40 were within genes, and the genes underlying 20 MTAs had annotations suggesting …

Stolon Development And Cultural Production Practices Of Winter-Grown Strawberries, Donna M. Morrison, Erin Blankenship, Paul Read, Ellen Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

The four experiments described here are part of a 5-year program focused on determining whether day-neutral and short-day strawberries would be suitable for commercial offseason/ winter (temperate climate) production in greenhouses. All research was performed using container-grown plants fertigated through a capillary mat production system with heat supplied under the benches. The first experiment focused on stolon development. The second experiment investigated the influence of stolon removal on berry production and included the removal of flowers for the first three weeks. The third and fourth experiments were conducted as a comparison of university research (experiment 3) versus a commercial operation …

Wildland Fire Science Literacy: Education, Creation, And Application, Devan Allen Mcgranahan, Carissa L. Wonkka

Department of Agronomy and Horticulture: Faculty Publications

Wildland fire science literacy is the capacity for wildland fire professionals to understand and communicate three aspects of wildland fire: (1) the fundamentals of fuels and fire behavior, (2) the concept of fire as an ecological regime, and (3) multiple human dimensions of wildland fire and the socio-ecological elements of fire regimes. Critical to wildland fire science literacy is a robust body of research on wildland fire. Here, we describe how practitioners, researchers, and other professionals can study, create, and apply robust wildland fire science. We begin with learning and suggest that the conventional fire ecology canon include detail on …

An Exome-Seq Based Tool For Mapping And Selection Of Candidate Genes In Maize Deletion Mutants, Shangang Jia, Kyla Morton, Chi Zhang, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Despite the large number of genomic and transcriptomic resources in maize, there is still much to learn about the function of genes in developmental and biochemical processes. Some maize mutants that were generated by gamma-irradiation showed clear segregation for the kernel phenotypes in B73 X Mo17 F2 ears. To better understand the functional genomics of kernel development, we developed a mapping and gene identification pipeline, bulked segregant exome sequencing (BSEx-seq), to map mutants with kernel phenotypes including opaque endosperm and reduced kernel size. BSEx-seq generates and compares the sequence of the exon fraction from mutant and normal plant F2 DNA …

Genetic Architecture Of Soybean Yield And Agronomic Traits, Brian W. Diers, Jim Specht, Katy Martin Rainey, Perry Cregan, Qijian Song, Vishnu Ramasubramanian, George Graef, Randall L. Nelson, William Schapaugh, Dechun Wang, Grover Shannon, Leah Mchale, Stella K. Kantartzi, Alencar Xavier, Rouf Mian, Robert M. Stupar, Jean-Michel Michno, Yong-Qiang Charles An, Wolfgang Goettel, Russell Ward, Carolyn Fox, Alexander E. Lipka, David Hyten, Troy Cary, William D. Beavis

Department of Agronomy and Horticulture: Faculty Publications

Soybean is the world’s leading source of vegetable protein and demand for its seed continues to grow. Breeders have successfully increased soybean yield, but the genetic architecture of yield and key agronomic traits is poorly understood. We developed a 40-mating soybean nested association mapping (NAM) population of 5,600 inbred lines that were characterized by single nucleotide polymorphism (SNP) markers and six agronomic traits in field trials in 22 environments. Analysis of the yield, agronomic, and SNP data revealed 23 significant marker-trait associations for yield, 19 for maturity, 15 for plant height, 17 for plant lodging, and 29 for seed mass. …

Influence Of Harvest Date On Seed Yield And Quality In Forage Kochia, Cody F. Creech, Blair L. Waldron, Corey V. Ransom, Dale R. Zobell, Joseph Earl Creech

Department of Agronomy and Horticulture: Faculty Publications

Forage kochia (Bassia prostrata) is used for rangeland reclamation and livestock and wildlife forage, but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies virescens and grisea. Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most accessions. Cultivar Snowstorm and breeding line Sahsel, both subsp. grisea, had the greatest 100-seed weights in November, 155 …

Transient Heat Stress During Early Seed Development Primes Germination And Seedling Establishment In Rice, Kevin Begcy, Jaspreet Sandhu, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Rice yield is highly sensitive to increased temperature. Given the trend of increasing global temperatures, this sensitivity to higher temperatures poses a challenge for achieving global food security. Early seed development in rice is highly sensitive to unfavorable environmental conditions. Heat stress (HS) during this stage decreases seed size and fertility, thus reducing yield. Here, we explore the transgenerational phenotypic consequences of HS during early seed development on seed viability, germination, and establishment. To elucidate the impact of HS on the developmental events in postzygotic rice seeds, we imposed moderate (35°C) and severe (39°C) HS treatments initiated 1 day after …

Maize And Soybean Root Front Velocity And Maximum Depth In Iowa, Usa, Raziel A. Ordóñez, Michael J. Castellano, J. L. Hatfield, M. J. Helmers, Mark A. Licht, Matt Liebman, Ranae Dietzel, Rafael Martinez-Feria, Javed Iqbal, Laila A. Puntel, S. Carolina Córdova, Kaitlin Togliatti, Emily E. Wright, Sotirios V. Archontoulis

Department of Agronomy and Horticulture: Faculty Publications

Quantitative measurements of root traits can improve our understanding of how crops respond to soil and weather conditions, but such data are rare. Our objective was to quantify maximum root depth and root front velocity (RFV) for maize (Zea mays) and soybean (Glycine max) crops across a range of growing conditions in the Midwest USA. Two sets of root measurements were taken every 10–15 days: in the crop row (in-row) and between two crop rows (center-row) across six Iowa sites having different management practices such as planting dates and drainage systems, totaling 20 replicated experimental treatments. …

Sequences Involved In Plant Yield And Methods Of Using, Harkamal Walia, Dante Placido, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Nucleic acid sequences involved in plant yield are provided, as are methods of using such nucleic acid sequences .

Building Resilience In Social-Ecological Food Systems In Vermont, Kristine Lien Skog, Stine Elisabeth Eriksen, Christy Anderson Brekken, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

There is an expanding interest in Local Food Systems (LFSs) in Vermont, United States, along with a growing effort to create adaptive governance to facilitate action. In this case study, we investigate how adaptive governance of LFS can provide ideas and act as a catalyst for creating resilience in other social-ecological systems (SESs). By participating in meetings and interviewing stakeholders inside and outside the Vermont LFS network, we found that consumers were highly motivated to participate by supporting environmental issues, the local economy, and interactive communities, as well as building social relationships. Farmers experienced better income and increased respect in …

Identification Of Quantitative Trait Loci Conferring Resistance To Tan Spot In A Biparental Population Derived From Two Nebraska Hard Red Winter Wheat Cultivars, Gayan K. Kariyawasam, Waseem Hussain, Amanda Easterly, Mary Guttieri, Vikas Belamkar, Jesse Poland, Jorge Venegas, Stephen Baenziger, Francois Marais, Jack B. Rasmussen, Zhaohui Liu

Department of Agronomy and Horticulture: Faculty Publications

Tan spot, caused by Pyrenophora triticirepentis (Ptr), is a destructive foliar disease in all types of cultivated wheat worldwide. Genetics of tan spot resistance in wheat is complex, involving insensitivity to fungal-produced necrotrophic effectors (NEs), major resistance genes, and quantitative trait loci (QTL) conferring race-nonspecific and race-specific resistance. The Nebraska hard red winter wheat (HRWW) cultivar ‘Wesley’ is insensitive to Ptr ToxA and highly resistant to multiple Ptr races, but the genetics of resistance in this cultivar is unknown. In this study, we used a recombinant inbred line (RIL) population derived from a cross between Wesley and another …

Active-Optical Reflectance Sensing Corn Algorithms Evaluated Over The United States Midwest Corn Belt, G. M. Bean, N. R. Kitchen, J. J. Camberato, R. B. Ferguson, F. G. Fernandez, D. W. Franzen, C. A. M. Laboski, E. D. Nafziger, J. E. Sawyer, P. C. Scharf, J. Schepers, J. S. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Uncertainty exists with corn (Zea mays L.) N management due to year-to-year variation in crop N need, soil N supply, and N loss from leaching, volatilization, and denitrification. Activeoptical reflectance sensing (AORS) has proven effective in some fields for generating N fertilizer recommendations that improve N use efficiency, but locally derived (e.g., within a US state) AORS algorithms have not been tested simultaneously across a broad region. The objective of this research was to evaluate locally developed AORS algorithms across the US Midwest Corn Belt region for making in-season corn N recommendations. Forty-nine N response trials were conducted across …

Substantial Contribution Of Genetic Variation In The Expression Of Transcription Factors To Phenotypic Variation Revealed By Erd-Gwas, Hung-Ying Lin, Qiang Liu, Xiao Li, Jinliang Yang, Sanzhen Liu, Yinlian Huang, Michael J. Scanlon, Dan Nettleton, Patrick S. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Background: There are significant limitations in existing methods for the genome-wide identification of genes whose expression patterns affect traits.

Results: The transcriptomes of five tissues from 27 genetically diverse maize inbred lines were deeply sequenced to identify genes exhibiting high and low levels of expression variation across tissues or genotypes. Transcription factors are enriched among genes with the most variation in expression across tissues, as well as among genes with higher-than-median levels of variation in expression across genotypes. In contrast, transcription factors are depleted among genes whose expression is either highly stable or highly variable across genotypes. We developed a …

Estimation Of Irrigation Requirements For Drip-Irrigated Maize In A Sub-Humid Climate, Liu Yang, Hai-Shun Yang, Jiu-Sheng Li, Yan-Feng Li, Hai-Jun Yan

Department of Agronomy and Horticulture: Faculty Publications

Drip-irrigation is increasingly applied in maize (Zea mays L.) production in sub-humid region. It is critical to quantify irrigation requirements during different growth stages under diverse climatic conditions. In this study, the Hybrid-Maize model was calibrated and applied in a sub-humid Heilongjiang Province in Northeast China to estimate irrigation requirements for drip irrigated maize during different crop physiological development stages and under diverse agro-climatic conditions. Using dimensionless scales, the whole growing season of maize was divided into diverse development stages from planting to maturity. Drip-irrigation dates and irrigation amounts in each irrigation event were simulated and summarized in 30-year simulation …

Identifying Ecologically Relevant Scales Of Habitat Selection: Diel Habitat Selection In Elk, Caleb P. Roberts, James W. Cain Iii, Robert D. Cox

Department of Agronomy and Horticulture: Faculty Publications

Although organisms make resource selection decisions at multiple spatiotemporal scales, not all scales are ecologically relevant to any given organism. Ecological patterns and rhythms such as behavioral and climatic patterns may provide a consistent method for identifying ecologically relevant scales of habitat selection. Using elk (Cervus canadensis) as an example species, we sought to test the ability of behavioral patterns to empirically partition diel scales for modeling habitat selection. We used model selection to partition diel scales by shifts in dominant behavior and then used resource selection probability functions to model elk habitat selection hierarchically at diel scales within seasons. …