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Historical Nitrogen Fertilizer Use In Agricultural Ecosystems Of The Contiguous United States During 1850–2015: Application Rate, Timing, And Fertilizer Types, Peiyu Cao, Chaoqun (Crystal) Lu, Zhen Yu Jun 2018

Historical Nitrogen Fertilizer Use In Agricultural Ecosystems Of The Contiguous United States During 1850–2015: Application Rate, Timing, And Fertilizer Types, Peiyu Cao, Chaoqun (Crystal) Lu, Zhen Yu

Ecology, Evolution and Organismal Biology Publications

A tremendous amount of anthropogenic nitrogen (N) fertilizer has been applied to agricultural lands to promote crop production in the US since the 1850s. However, inappropriate N management practices have caused numerous ecological and environmental problems which are difficult to quantify due to the paucity of spatially explicit time-series fertilizer use maps. Understanding and assessing N fertilizer management history could provide important implications for enhancing N use efficiency and reducing N loss. In this study, we therefore developed long-term gridded maps to depict crop-specific N fertilizer use rates, application timing, and the fractions of ammonium N (NH+ 4 -N) and ...


Variability In Community Productivity—Mediating Effects Of Vegetation Attributes, H. Wayne Polley, Brian J. Wilsey May 2018

Variability In Community Productivity—Mediating Effects Of Vegetation Attributes, H. Wayne Polley, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

  1. Plant productivity varies through time in response to environmental fluctuations. Reducing variability in productivity requires an improved understanding of how plant community attributes interact with environmental fluctuations to influence plant growth dynamics. We evaluated links between two community attributes, species diversity and abundance‐weighted values of specific leaf area (SLA), and temporal variability in grassland productivity at patch (local) and aggregate (multipatch) spatial scales.
  2. Aggregate communities were created by combining patches of spatially distinct communities of perennial plant species from grassland biodiversity experiments in Texas, USA. Interannual variability in above‐ground net primary productivity (ANPP) of aggregate communities was analysed ...


Herbivory And Eutrophication Mediate Grassland Plant Nutrient Responses Across A Global Climatic Gradient, T. Michael Anderson, Daniel M. Griffith, James B. Grace, Eric M. Lind, Peter B. Adler, Lori A. Biederman, Dana M. Blumenthal, Pedro Daleo, Jennifer Firn, Nicole Hagenah, W. Stanley Harpole, Andrew S. Macdougall, Rebecca L. Mcculley, Suzanne M. Prober, Anita C. Risch, Mahesh Sankaran, Martin Schutz, Eric W. Seabloom, Carly J. Stevens, Lauren L. Sullivan, Peter D. Wragg, Elizabeth T. Borer Apr 2018

Herbivory And Eutrophication Mediate Grassland Plant Nutrient Responses Across A Global Climatic Gradient, T. Michael Anderson, Daniel M. Griffith, James B. Grace, Eric M. Lind, Peter B. Adler, Lori A. Biederman, Dana M. Blumenthal, Pedro Daleo, Jennifer Firn, Nicole Hagenah, W. Stanley Harpole, Andrew S. Macdougall, Rebecca L. Mcculley, Suzanne M. Prober, Anita C. Risch, Mahesh Sankaran, Martin Schutz, Eric W. Seabloom, Carly J. Stevens, Lauren L. Sullivan, Peter D. Wragg, Elizabeth T. Borer

Ecology, Evolution and Organismal Biology Publications

Plant stoichiometry, the relative concentration of elements, is a key regulator of ecosystem functioning and is also being altered by human activities. In this paper we sought to understand the global drivers of plant stoichiometry and compare the relative contribution of climatic vs. anthropogenic effects. We addressed this goal by measuring plant elemental (C, N, P and K) responses to eutrophication and vertebrate herbivore exclusion at eighteen sites on six continents. Across sites, climate and atmospheric N deposition emerged as strong predictors of plot‐level tissue nutrients, mediated by biomass and plant chemistry. Within sites, fertilization increased total plant nutrient ...


Priority Effects Are Affected By Precipitation Variability And Are Stronger In Exotic Than Native Grassland Species, Kaitlin M. Goodale, Brian J. Wilsey Apr 2018

Priority Effects Are Affected By Precipitation Variability And Are Stronger In Exotic Than Native Grassland Species, Kaitlin M. Goodale, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

Exotic perennial grassland species often green up earlier than their native counterparts, allowing them to gain an advantage by dominating resources early (priority effects). Precipitation variability is expected to increase with climate change, and may alter the strength of priority effects. We hypothesized that exotics will have stronger priority effects than natives, precipitation variability will impact the strength of priority effects, and precipitation variability will impact the priority effects of native species more than those of exotics. We seeded one of five native or five exotic grassland species from the Central U.S. spanning multiple functional groups 28 days prior ...


Ecological Factors Associated With Pre-Dispersal Predation Of Fig Seeds And Wasps By Fig-Specialist Lepidopteran Larvae, Finn Piatscheck, Justin Van Goor, Derek D. Houston, John D. Nason Mar 2018

Ecological Factors Associated With Pre-Dispersal Predation Of Fig Seeds And Wasps By Fig-Specialist Lepidopteran Larvae, Finn Piatscheck, Justin Van Goor, Derek D. Houston, John D. Nason

Ecology, Evolution and Organismal Biology Publications

In brood pollination mutualisms, predation of developing fruit can have large negative repercussions for both plant and pollinator population dynamics. The Sonoran Desert rock fig Ficus petiolaris and its highly-coevolved wasp pollinator are subject to frequent attack by lepidopteran larvae that consume fig fruit and the developing seeds and larval pollinators they contain. We used generalized linear mixed models to investigate how the phenology, quantity, and spatial distribution of fig fruits is associated with variation in lepidopteran damage intensity on individual trees at nine geographic locations spanning a 741 km latitudinal transect along Mexico’s Baja California Peninsula. We found ...


Phenology Differences Between Native And Novel Exotic‐Dominated Grasslands Rival The Effects Of Climate Change, Brian J. Wilsey, Leanne M. Martin, Andrew D. Kaul Mar 2018

Phenology Differences Between Native And Novel Exotic‐Dominated Grasslands Rival The Effects Of Climate Change, Brian J. Wilsey, Leanne M. Martin, Andrew D. Kaul

Ecology, Evolution and Organismal Biology Publications

1. Novel ecosystems can differ from the native systems they replaced. We used phenology measures to compare ecosystem functioning between novel exotic-dominated and native-dominated grasslands in the central U.S.

2. Phenology, or timing of biological events, is affected by climate and land use changes. We assessed how phenology shifts are being altered by exotic species dominance by comparing remotely sensed Normalized Difference Vegetation Index within growing seasons at exotic- and native-dominated sites along a latitudinal gradient. Exotic species were dominated by the C3 species functional group in the north and the C4 species functional group in the south.

3 ...


Core Cis-Element Variation Confers Subgenome-Biased Expression Of A Transcription Factor That Functions In Cotton Fiber Elongation, Bo Zhao, Jun-Feng Cao, Guan-Jing Hu, Zhi-Wen Chen, Lu-Yao Wang, Xiao-Xia Shangguan, Ling-Jian Wang, Ying-Bo Mao, Tian-Zhen Zhang, Jonathan F. Wendel, Xiao-Ya Chen Jan 2018

Core Cis-Element Variation Confers Subgenome-Biased Expression Of A Transcription Factor That Functions In Cotton Fiber Elongation, Bo Zhao, Jun-Feng Cao, Guan-Jing Hu, Zhi-Wen Chen, Lu-Yao Wang, Xiao-Xia Shangguan, Ling-Jian Wang, Ying-Bo Mao, Tian-Zhen Zhang, Jonathan F. Wendel, Xiao-Ya Chen

Ecology, Evolution and Organismal Biology Publications

  • Cotton cultivars have evolved to produce extensive, long, seed-born fibers important for the textile industry, but we know little about the molecular mechanism underlying spinnable fiber formation. Here, we report how PACLOBUTRAZOL RESISTANCE 1 (PRE1) in cotton, which encodes a basic helix-loop-helix (bHLH) transcription factor, is a target gene of spinnable fiber evolution.
  • Differential expression of homoeologous genes in polyploids is thought to be important to plant adaptation and novel phenotypes. PRE1 expression is specific to cotton fiber cells, upregulated during their rapid elongation stage and A-homoeologous biased in allotetraploid cultivars. Transgenic studies demonstrated that PRE1 is a positive regulator ...


Herbivores Safeguard Plant Diversity By Reducing Variability In Dominance, Brent Mortensen, Brent Danielson, W. Stan Harpole, Juan Alberti, Carlos Alberto Arnillas, Lori Biederman, Elizabeth T. Borer, Marc W. Cadotte, John M. Dwyer, Nicole Hagenah, Yann Hautier, Pablo Luis Peri, Eric W. Seabloom Jan 2018

Herbivores Safeguard Plant Diversity By Reducing Variability In Dominance, Brent Mortensen, Brent Danielson, W. Stan Harpole, Juan Alberti, Carlos Alberto Arnillas, Lori Biederman, Elizabeth T. Borer, Marc W. Cadotte, John M. Dwyer, Nicole Hagenah, Yann Hautier, Pablo Luis Peri, Eric W. Seabloom

Ecology, Evolution and Organismal Biology Publications

1. Reductions in community evenness can lead to local extinctions as dominant species exclude subordinate species; however, herbivores can prevent competitive exclusion by consuming otherwise dominant plant species, thus increasing evenness. While these predictions logically result from chronic, gradual reductions in evenness, rapid, temporary pulses of dominance may also reduce species richness. Short pulses of dominance can occur as biotic or abiotic conditions temporarily favor one or a few species, manifested as increased temporal variability (the inverse of temporal stability) in community evenness. Here, we tested whether consumers help maintain plant diversity by reducing the temporal variability in community evenness ...


Tropical Tree Species Traits Drive Soil Cation Dynamics Via Effects On Ph: A Proposed Conceptual Framework, Ann E. Russell, Steven J. Hall, James W. Raich Nov 2017

Tropical Tree Species Traits Drive Soil Cation Dynamics Via Effects On Ph: A Proposed Conceptual Framework, Ann E. Russell, Steven J. Hall, James W. Raich

Ecology, Evolution and Organismal Biology Publications

Humid tropical forests are major players in the global carbon cycle, despite evidence that cations (rock‐derived, positively charged ions) can limit or co‐limit net primary productivity (NPP). In mature forests, tight cation cycling, i.e., without leaching losses, could maintain cation stocks on site. That mechanism does not explain how regenerating tropical secondary forest trees start from seeds and accrue large cation stocks in biomass, when growing on soils depleted in available cations. We propose a new mechanism that links tree species’ traits to soil cation availability via impacts on soil pH, a master biogeochemical driver. We tested ...


Diversity-Dependent Temporal Divergence Of Ecosystem Functioning In Experimental Ecosystems, Nathaly R. Guerrero-Ramírez, Dylan Craven, Peter B. Reich, John J. Ewel, Forest Isbell, Julia Koricheva, John A. Parrotta, Harald Auge, Heather E. Ericson, David I. Forrester, Andy Hector, Jasmin Joshi, Florencia Montagnini, Cecilia Palmborg, Daniel Piotto, Catherine Potvin, Christiane Roscher, Jasper Van Ruijven, David Tilman, Brian Wilsey, Nico Eisenhauer Nov 2017

Diversity-Dependent Temporal Divergence Of Ecosystem Functioning In Experimental Ecosystems, Nathaly R. Guerrero-Ramírez, Dylan Craven, Peter B. Reich, John J. Ewel, Forest Isbell, Julia Koricheva, John A. Parrotta, Harald Auge, Heather E. Ericson, David I. Forrester, Andy Hector, Jasmin Joshi, Florencia Montagnini, Cecilia Palmborg, Daniel Piotto, Catherine Potvin, Christiane Roscher, Jasper Van Ruijven, David Tilman, Brian Wilsey, Nico Eisenhauer

Ecology, Evolution and Organismal Biology Publications

The effects of biodiversity on ecosystem functioning generally increase over time, but the underlying processes remain unclear. Using 26 long-term grassland and forest experimental ecosystems, we demonstrate that biodiversity–ecosystem functioning relationships strengthen mainly by greater increases in functioning in high-diversity communities in grasslands and forests. In grasslands, biodiversity effects also strengthen due to decreases in functioning in low-diversity communities. Contrasting trends across grasslands are associated with differences in soil characteristics.


How Do Nutrients Change Flowering In Prairies?, Lori Biederman, Brent Mortensen, Philip Fay, Nicole Hagenah, Johannes Knops, Kimberly La Pierre, Ramesh Laungani, Eric Lind, Rebecca Mcculley, Sally Power, Eric Seabloom, Pedro Tognetti Sep 2017

How Do Nutrients Change Flowering In Prairies?, Lori Biederman, Brent Mortensen, Philip Fay, Nicole Hagenah, Johannes Knops, Kimberly La Pierre, Ramesh Laungani, Eric Lind, Rebecca Mcculley, Sally Power, Eric Seabloom, Pedro Tognetti

Ecology, Evolution and Organismal Biology Publications

Farmers today apply more synthetic fertilizers to farm fields than ever before – but not all of these nutrients are used by crops: some fertilizer escapes through the air, soil, or water. Nitrogen, phosphorous, and potassium flow off farm fields when it rains, billow into the air when fields are plowed, and drift with the wind to other areas. Extra nutrients are also released to the air when people burn fossil fuels. We wanted to find out: what happens when these extra nutrients land on wild prairie ecosystems? How do its wild plants respond? Do they all just grow better? Or ...


Nutrient Addition Shifts Plant Community Composition Towards Earlier Flowering Species In Some Prairie Ecoregions In The U.S. Central Plains, Lori A. Biederman, Brent Mortensen, Philip Fay, Nicole Hagenah, Johannes Knops, Kimberly La Pierre, Ramesh Laungani, Eric Lind, Rebecca Mcculley, Sally Power, Eric Seabloom, Pedro Tognetti May 2017

Nutrient Addition Shifts Plant Community Composition Towards Earlier Flowering Species In Some Prairie Ecoregions In The U.S. Central Plains, Lori A. Biederman, Brent Mortensen, Philip Fay, Nicole Hagenah, Johannes Knops, Kimberly La Pierre, Ramesh Laungani, Eric Lind, Rebecca Mcculley, Sally Power, Eric Seabloom, Pedro Tognetti

Ecology, Evolution and Organismal Biology Publications

The distribution of flowering across the growing season is governed by each species’ evolutionary history and climatic variability. However, global change factors, such as eutrophication and invasion, can alter plant community composition and thus change the distribution of flowering across the growing season. We examined three ecoregions (tall-, mixed, and short-grass prairie) across the U.S. Central Plains to determine how nutrient (nitrogen (N), phosphorus, and potassium (+micronutrient)) addition alters the temporal patterns of plant flowering traits. We calculated total community flowering potential (FP) by distributing peak-season plant cover values across the growing season, allocating each species’ cover to only ...


Species Composition But Not Diversity Explains Recovery From The 2011 Drought In Texas Grasslands, Xia Xu, H. Wayne Polley, Kirsten S. Hofmockel, Brian J. Wilsey Mar 2017

Species Composition But Not Diversity Explains Recovery From The 2011 Drought In Texas Grasslands, Xia Xu, H. Wayne Polley, Kirsten S. Hofmockel, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

Extreme droughts can have profound direct consequences for grassland ecosystems, but it is poorly known how ecosystems recover from drought and what ecological factors are associated with recovery. Recovery occurs when ecosystem functioning returns to values observed prior to a perturbation. Here, we tested for ecosystem recovery after an extreme drought in 2011 in previously established native and exotic experimental communities in Central Texas. Planted mixtures of all native and all exotic species were crossed with a summer irrigation treatment, with eight community compositions (random draws) per treatment. Prior to the drought, native plots had higher diversity than exotic plots ...


Genetic Diversity And Population Structure Of The Threatened Temperate Woody Bamboo Kuruna Debilis (Poaceae: Bambusoideae: Arundinarieae) From Sri Lanka Based On Microsatellite Analysis, Lakshmi Attigala, Timothy Gallaher, John Nason, Lynn G. Clark Mar 2017

Genetic Diversity And Population Structure Of The Threatened Temperate Woody Bamboo Kuruna Debilis (Poaceae: Bambusoideae: Arundinarieae) From Sri Lanka Based On Microsatellite Analysis, Lakshmi Attigala, Timothy Gallaher, John Nason, Lynn G. Clark

Ecology, Evolution and Organismal Biology Publications

Species of the temperate woody bamboo genus Kuruna Attigala, Kathriar. & L.G. Clark (Poaceae: Bambusoideae) distributed in Sri Lanka and southern India, are threatened due to deforestation and habitat fragmentation. The current study focused on the tetraploid woody bamboo Kuruna debilis (Thwaites) Attigala, Kathriar. & L.G. Clark, using twelve variable microsatellite loci to assess the genetic diversity and population structure in six known Sri Lankan populations. Due to the rarity of the species, an exhaustive sampling of accessible plants resulted in a total of only 28 individuals. Nonetheless, the allelic diversity was high at most loci and given the limited ...


Direct Nitrous Oxide Emissions In Mediterranean Climate Cropping Systems: Emission Factors Based On A Meta-Analysis Of Available Measurement Data, Maria L. Cayuela, Eduardo Aguilera, Alberto Sanz-Cobena, Dean C. Adams, Diego Abalos, Louise Barton, Rebecca Ryals, Whendee L. Silver, Marta A. Alfaro, Valentini A. Pappa, Pete Smith, Josette Garnier, Gilles Billen, Lex Bouwman, Alberte Bondeau, Luis Lassaletta Feb 2017

Direct Nitrous Oxide Emissions In Mediterranean Climate Cropping Systems: Emission Factors Based On A Meta-Analysis Of Available Measurement Data, Maria L. Cayuela, Eduardo Aguilera, Alberto Sanz-Cobena, Dean C. Adams, Diego Abalos, Louise Barton, Rebecca Ryals, Whendee L. Silver, Marta A. Alfaro, Valentini A. Pappa, Pete Smith, Josette Garnier, Gilles Billen, Lex Bouwman, Alberte Bondeau, Luis Lassaletta

Ecology, Evolution and Organismal Biology Publications

Many recent reviews and meta‐analyses of N2O emissions do not include data from Mediterranean studies. In this paper we present a meta‐analysis of the N2O emissions from Mediterranean cropping systems, and propose a more robust and reliable regional emission factor (EF) for N2O, distinguishing the effects of water management, crop type, and fertilizer management. The average overall EF for Mediterranean agriculture (EFMed) is 0.5%, which is substantially lower than the IPCC default value of 1%. Soil properties had no significant effect on EFs for N2O. Increasing the nitrogen fertilizer rate led to higher EFs; when N was ...


Global Gross Primary Productivity And Water Use Efficiency Changes Under Drought Stress, Zhen Yu, Jingxin Wang, Shirong Liu, James S. Rentch, Pengsen Sun, Chaoqun (Crystal) Lu Jan 2017

Global Gross Primary Productivity And Water Use Efficiency Changes Under Drought Stress, Zhen Yu, Jingxin Wang, Shirong Liu, James S. Rentch, Pengsen Sun, Chaoqun (Crystal) Lu

Ecology, Evolution and Organismal Biology Publications

Drought can affect the structure, composition and function of terrestrial ecosystems, yet drought impacts and post-drought recovery potentials of different land cover types have not been extensively studied at a global scale. We evaluated drought impacts on gross primary productivity (GPP), evapotranspiration (ET), and water use efficiency (WUE) of different global terrestrial ecosystems, as well as the drought-resilience of each ecosystem type during the period of 2000 to 2011. Using GPP as biome vitality indicator against drought stress, we developed a model to examine ecosystem resilience represented by the length of recovery days (LRD). LRD presented an evident gradient of ...


Diversity Analysis Of Cotton (Gossypium Hirsutum L.) Germplasm Using The Cottonsnp63k Array, Jonathan F. Wendel, Lori L. Hinze, Amanda M. Hulse-Kemp, Iain W. Wilson, Qian-Hao Zhu, Danny J. Llewellyn, Jen M. Taylor, Andrew Spriggs, David D. Fang, Mauricio Ulloa, John J. Burke, Marc Giband, Jean-Marc Lacape, Allen Van Deynze, Joshua A. Udall, Jodi A. Scheffler, Steve Hague, Alan E. Pepper, James Frelichowski, Cindy T. Lawley, Don C. Jones, Richard G. Percy, David M. Stelly Jan 2017

Diversity Analysis Of Cotton (Gossypium Hirsutum L.) Germplasm Using The Cottonsnp63k Array, Jonathan F. Wendel, Lori L. Hinze, Amanda M. Hulse-Kemp, Iain W. Wilson, Qian-Hao Zhu, Danny J. Llewellyn, Jen M. Taylor, Andrew Spriggs, David D. Fang, Mauricio Ulloa, John J. Burke, Marc Giband, Jean-Marc Lacape, Allen Van Deynze, Joshua A. Udall, Jodi A. Scheffler, Steve Hague, Alan E. Pepper, James Frelichowski, Cindy T. Lawley, Don C. Jones, Richard G. Percy, David M. Stelly

Ecology, Evolution and Organismal Biology Publications

Background

Cotton germplasm resources contain beneficial alleles that can be exploited to develop germplasm adapted to emerging environmental and climate conditions. Accessions and lines have traditionally been characterized based on phenotypes, but phenotypic profiles are limited by the cost, time, and space required to make visual observations and measurements. With advances in molecular genetic methods, genotypic profiles are increasingly able to identify differences among accessions due to the larger number of genetic markers that can be measured. A combination of both methods would greatly enhance our ability to characterize germplasm resources. Recent efforts have culminated in the identification of sufficient ...


A New Species Of Cotton From Wake Atoll,Gossypium Stephensii(Malvaceae), Jonathan F. Wendel, Joseph P. Gallagher, Corrinne E. Grover, Kristen Rex, Matthew Moran Jan 2017

A New Species Of Cotton From Wake Atoll,Gossypium Stephensii(Malvaceae), Jonathan F. Wendel, Joseph P. Gallagher, Corrinne E. Grover, Kristen Rex, Matthew Moran

Ecology, Evolution and Organismal Biology Publications

Wake Atoll is an isolated chain of three islets located in the Western Pacific. Included in its endemic flora is a representative of the genus Gossypium colloquially referred to as Wake Island cotton. Stanley G. Stephens pointed out that “Wake Island cotton does not resemble closely either the Caribbean or other Pacific forms.” Taking into consideration morphological distinctions, the geographic isolation of Wake Atoll, and newly generated molecular data presented here, we conclude that the cottons of Wake Atoll do in fact represent a new species of Gossypium, here named Gossypium stephensii. This name is chosen to commemorate the eminent ...


Global Manure Nitrogen Production And Application In Cropland During 1860–2014: A 5 Arcmin Gridded Global Dataset For Earth System Modeling, Bowen Zhang, Hanqin Tian, Chaoqun (Crystal) Lu, Shree R.S. Dangal, Jia Yang, Shufen Pan Jan 2017

Global Manure Nitrogen Production And Application In Cropland During 1860–2014: A 5 Arcmin Gridded Global Dataset For Earth System Modeling, Bowen Zhang, Hanqin Tian, Chaoqun (Crystal) Lu, Shree R.S. Dangal, Jia Yang, Shufen Pan

Ecology, Evolution and Organismal Biology Publications

Given the important role of nitrogen input from livestock systems in terrestrial nutrient cycles and the atmospheric chemical composition, it is vital to have a robust estimation of the magnitude and spatiotemporal variation in manure nitrogen production and its application to cropland across the globe. In this study, we used the dataset from the Global Livestock Impact Mapping System (GLIMS) in conjunction with country-specific annual livestock populations to reconstruct the manure nitrogen production during 1860–2014. The estimated manure nitrogen production increased from 21.4TgNyr−1 in 1860 to 131.0TgNyr−1 in 2014 with a significant annual increasing trend ...


Uncertainty In The Response Of Terrestrial Carbon Sink To Environmental Drivers Undermines Carbon-Climate Feedback Predictions, D.N. Huntzinger, A.M. Michalak, C. Schwalm, P. Ciais, A.W. King, Y. Fang, K. Schaefer, Y. Wei, R.B. Cook, J.B. Fisher, D. Hayes, M. Huang, A. Ito, A.K. Jain, H. Lei, Chaoqun (Crystal) Lu, F. Maignan, J. Mao, N. Parazoo, S. Peng, B. Poulter, D. Ricciuto, X. Shi, H. Tian, W. Wang, N. Zeng, F. Zhao Jan 2017

Uncertainty In The Response Of Terrestrial Carbon Sink To Environmental Drivers Undermines Carbon-Climate Feedback Predictions, D.N. Huntzinger, A.M. Michalak, C. Schwalm, P. Ciais, A.W. King, Y. Fang, K. Schaefer, Y. Wei, R.B. Cook, J.B. Fisher, D. Hayes, M. Huang, A. Ito, A.K. Jain, H. Lei, Chaoqun (Crystal) Lu, F. Maignan, J. Mao, N. Parazoo, S. Peng, B. Poulter, D. Ricciuto, X. Shi, H. Tian, W. Wang, N. Zeng, F. Zhao

Ecology, Evolution and Organismal Biology Publications

Terrestrial ecosystems play a vital role in regulating the accumulation of carbon (C) in the atmosphere. Understanding the factors controlling land C uptake is critical for reducing uncertainties in projections of future climate. The relative importance of changing climate, rising atmospheric CO2, and other factors, however, remains unclear despite decades of research. Here, we use an ensemble of land models to show that models disagree on the primary driver of cumulative C uptake for 85% of vegetated land area. Disagreement is largest in model sensitivity to rising atmospheric CO2 which shows almost twice the variability in cumulative land uptake since ...


Gene-Body Cg Methylation And Divergent Expression Of Duplicate Genes In Rice, Jonathan F. Wendel, Xutong Wang, Zhibin Zhang, Tiansi Fu, Lanjuan Hu, Chunming Xu, Lei Gong Jan 2017

Gene-Body Cg Methylation And Divergent Expression Of Duplicate Genes In Rice, Jonathan F. Wendel, Xutong Wang, Zhibin Zhang, Tiansi Fu, Lanjuan Hu, Chunming Xu, Lei Gong

Ecology, Evolution and Organismal Biology Publications

Gene and genome duplication fosters genetic novelty, but redundant gene copies would undergo mutational decay unless preserved via selective or neutral forces. Molecular mechanisms mediating duplicate preservation remain incompletely understood. Several recent studies showed an association between DNA methylation and expression divergence of duplicated genes and suggested a role of epigenetic mechanism in duplicate retention. Here, we compare genome-wide gene-body CG methylation (BCGM) and duplicate gene expression between a rice mutant null for OsMet1-2(a major CG methytransferase in rice) and its isogenic wild-type. We demonstrate a causal link between BCGM divergence and expression difference of duplicate copies. Interestingly, the ...


Global Nitrogen And Phosphorus Fertilizer Use For Agriculture Production In The Past Half Century: Shifted Hot Spots And Nutrient Imbalance, Chaoqun (Crystal) Lu, Hanqin Tian Jan 2017

Global Nitrogen And Phosphorus Fertilizer Use For Agriculture Production In The Past Half Century: Shifted Hot Spots And Nutrient Imbalance, Chaoqun (Crystal) Lu, Hanqin Tian

Ecology, Evolution and Organismal Biology Publications

In addition to enhancing agricultural productivity, synthetic nitrogen (N) and phosphorous (P) fertilizer application in croplands dramatically alters global nutrient budget, water quality, greenhouse gas balance, and their feedback to the climate system. However, due to the lack of geospatial fertilizer input data, current Earth system and land surface modeling studies have to ignore or use oversimplified data (e.g., static, spatially uniform fertilizer use) to characterize agricultural N and P input over decadal or century-long periods. In this study, we therefore develop global time series gridded data of annual synthetic N and P fertilizer use rate in agricultural lands ...


Interannual Water-Level Fluctuations And The Vegetation Of Prairie Potholes: Potential Impacts Of Climate Change, Arnold G. Van Der Valk, David M. Mushet Dec 2016

Interannual Water-Level Fluctuations And The Vegetation Of Prairie Potholes: Potential Impacts Of Climate Change, Arnold G. Van Der Valk, David M. Mushet

Ecology, Evolution and Organismal Biology Publications

Mean water depth and range of interannual water-level fluctuations over wet-dry cycles in precipitation are major drivers of vegetation zone formation in North American prairie potholes. We used harmonic hydrological models, which require only mean interannual water depth and amplitude of water-level fluctuations over a wet–dry cycle, to examine how the vegetation zones in a pothole would respond to small changes in water depth and/or amplitude of water-level fluctuations. Field data from wetlands in Saskatchewan, North Dakota, and South Dakota were used to parameterize harmonic models for four pothole classes. Six scenarios in which small negative or positive ...


Plant Connectivity Underlies Plant‐Pollinator‐Exploiter Distributions In Ficus Petiolaris And Associated Pollinating And Non‐Pollinating Fig Wasps, A. Bradley Duthie, John D. Nason Nov 2016

Plant Connectivity Underlies Plant‐Pollinator‐Exploiter Distributions In Ficus Petiolaris And Associated Pollinating And Non‐Pollinating Fig Wasps, A. Bradley Duthie, John D. Nason

Ecology, Evolution and Organismal Biology Publications

Mutualism is ubiquitous in nature, and nursery pollination mutualisms provide a system well suited to quantifying the benefits and costs of symbiotic interactions. In nursery pollination mutualisms, pollinators reproduce within the inflorescence they pollinate, with benefits and costs being measured in the numbers of pollinator offspring and seeds produced. This type of mutualism is also typically exploited by seed-consuming nonpollinators that obtain resources from plants without providing pollination services. Theory predicts that the rate at which pollen-bearing “foundresses” visit a plant will strongly affect the plant's production of pollinator offspring, non-pollinator offspring, and seeds. Spatially aggregated plants are predicted ...


Plant Diversity Effects On Grassland Productivity Are Robust To Both Nutrient Enrichment And Drought, Dylan Craven, Forest Isbell, Pete Manning, John Connolly, Helge Bruelheide, Anne Ebeling, Christiane Roscher, Jasper Van Ruijven, Alexandra Weigelt, Brian J. Wilsey, Carl Beierkuhnlein, Enrica De Luca, John N. Griffin, Yann Hautier, Andy Hector, Anke Jentsch, Jürgen Kreyling, Vojtech Lanta, Michel Loreau, Sebastian T. Meyer, Akira S. Mori, Shahid Naeem, Cecilia Palmborg, H. Wayne Polley, Peter B. Reich, Bernhard Schmid, Alrun Siebenkäs, Eric Seabloom, Madhav P. Thakur, David Tilman, Anja Vogel, Nico Eisenhauer Apr 2016

Plant Diversity Effects On Grassland Productivity Are Robust To Both Nutrient Enrichment And Drought, Dylan Craven, Forest Isbell, Pete Manning, John Connolly, Helge Bruelheide, Anne Ebeling, Christiane Roscher, Jasper Van Ruijven, Alexandra Weigelt, Brian J. Wilsey, Carl Beierkuhnlein, Enrica De Luca, John N. Griffin, Yann Hautier, Andy Hector, Anke Jentsch, Jürgen Kreyling, Vojtech Lanta, Michel Loreau, Sebastian T. Meyer, Akira S. Mori, Shahid Naeem, Cecilia Palmborg, H. Wayne Polley, Peter B. Reich, Bernhard Schmid, Alrun Siebenkäs, Eric Seabloom, Madhav P. Thakur, David Tilman, Anja Vogel, Nico Eisenhauer

Ecology, Evolution and Organismal Biology Publications

Global change drivers are rapidly altering resource availability and biodiversity. While there is consensus that greater biodiversity increases the functioning of ecosystems, the extent to which biodiversity buffers ecosystem productivity in response to changes in resource availability remains unclear. We use data from 16 grassland experiments across North America and Europe that manipulated plant species richness and one of two essential resources—soil nutrients or water—to assess the direction and strength of the interaction between plant diversity and resource alteration on above-ground productivity and net biodiversity, complementarity, and selection effects. Despite strong increases in productivity with nutrient addition and ...


Evolution Of Plant Genome Architecture, Jonathan F. Wendel, Scott A. Jackson, Blake C. Meyers, Rod A. Wing Jan 2016

Evolution Of Plant Genome Architecture, Jonathan F. Wendel, Scott A. Jackson, Blake C. Meyers, Rod A. Wing

Ecology, Evolution and Organismal Biology Publications

We have witnessed an explosion in our understanding of the evolution and structure of plant genomes in recent years. Here, we highlight three important emergent realizations: (1) that the evolutionary history of all plant genomes contains multiple, cyclical episodes of whole-genome doubling that were followed by myriad fractionation processes; (2) that the vast majority of the variation in genome size reflects the dynamics of proliferation and loss of lineage-specific transposable elements; and (3) that various classes of small RNAs help shape genomic architecture and function. We illustrate ways in which understanding these organism-level and molecular genetic processes can be used ...


Evolution Of Plant Phenotypes, From Genomes To Traits, Jonathan F. Wendel, Josep M. Casacuberta, Scott Jackson, Olivier Panaud Jan 2016

Evolution Of Plant Phenotypes, From Genomes To Traits, Jonathan F. Wendel, Josep M. Casacuberta, Scott Jackson, Olivier Panaud

Ecology, Evolution and Organismal Biology Publications

Connecting genotype to phenotype is a grand challenge of biology. Over the past 50 years, there have been numerous and powerful advances to meet this challenge, including next-generation sequencing approaches (Jackson et al. 2011), molecular genetic mapping techniques, computational modeling, and the integration of evolutionary theory and tools. In plants, the long history of domestication and breeding has provided multiple insights into the genotype–phenotype equation (Meyer and Purugganan 2013; Olsen and Wendel 2013). Domestication and breeding provide unique systems with which to study the evolution of traits and adaptation to new environments. At present, agriculture faces unprecedented challenges, with ...


Independent Domestication Of Two Old World Cotton Species, Jonathan F. Wendel, Simon Renny-Byfield, Justin T. Page, Joshua A. Udall, William S. Sanders, Daniel G. Peterson, Mark A. Arick Ii, Corrinne E. Grover Jan 2016

Independent Domestication Of Two Old World Cotton Species, Jonathan F. Wendel, Simon Renny-Byfield, Justin T. Page, Joshua A. Udall, William S. Sanders, Daniel G. Peterson, Mark A. Arick Ii, Corrinne E. Grover

Ecology, Evolution and Organismal Biology Publications

Domesticated cotton species provide raw material for the majority of the world's textile industry. Two independent domestication events have been identified in allopolyploid cotton, one in Upland cotton ( Gossypium hirsutum L.) and the other to Egyptian cotton ( Gossypium barbadense L.). However, two diploid cotton species, Gossypium arboreum L. and Gossypium herbaceum L., have been cultivated for several millennia, but their status as independent domesticates has long been in question. Using genome resequencing data, we estimated the global abundance of various repetitive DNAs. We demonstrate that, despite negligible divergence in genome size, the two domesticated diploid cotton species contain different ...


Chloroplast Dna Structural Variation, Phylogeny, And Age Of Divergence Among Diploid Cotton Species, Jonathan F. Wendel, Zhiwen Chen, Kun Feng, Corrinne E. Grover, Pengbo Li, Fang Liu, Yumei Wang, Qin Xu, Mingzhao Shang, Zhongli Zhou, Xiaoyan Cai, Xingxing Wang, Kunbo Wang, Jinping Hua Jan 2016

Chloroplast Dna Structural Variation, Phylogeny, And Age Of Divergence Among Diploid Cotton Species, Jonathan F. Wendel, Zhiwen Chen, Kun Feng, Corrinne E. Grover, Pengbo Li, Fang Liu, Yumei Wang, Qin Xu, Mingzhao Shang, Zhongli Zhou, Xiaoyan Cai, Xingxing Wang, Kunbo Wang, Jinping Hua

Ecology, Evolution and Organismal Biology Publications

The cotton genus (Gossypium spp.) contains 8 monophyletic diploid genome groups (A, B, C, D, E, F, G, K) and a single allotetraploid clade (AD). To gain insight into the phylogeny of Gossypium and molecular evolution of the chloroplast genome in this group, we performed a comparative analysis of 19 Gossypium chloroplast genomes, six reported here for the first time. Nucleotide distance in non-coding regions was about three times that of coding regions. As expected, distances were smaller within than among genome groups. Phylogenetic topologies based on nucleotide and indel data support for the resolution of the 8 genome groups ...


An Examination Of Nucleotypic Effects In Diploid And Polyploid Cotton, Jonathan F. Wendel, S.J. Snodgrass, Josef J. Jareczek Jan 2016

An Examination Of Nucleotypic Effects In Diploid And Polyploid Cotton, Jonathan F. Wendel, S.J. Snodgrass, Josef J. Jareczek

Ecology, Evolution and Organismal Biology Publications

Nucleotypic effects are phenotypic changes related to the total nuclear DNA amount per cell. These effects are commonly observed among and within genera for certain cell types, and the generality of the positive correlation between genome size and cell size has been well established. However, there are few studies of nucleotypic effects which incorporate into the analysis both ploidy level and genome size (given as Mbp determined by 2C values). To test the hypothesis that cell size scales with genome size and ploidy, we measured the guard cell length, epidermal pavement cell surface area, and pollen grain diameter using individuals ...