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Full-Text Articles in Life Sciences
Variation In Seagrass-Associated Macroinvertebrate Communities Along The Gulf Coast Of Peninsular Florida: An Exploration Of Patterns And Ecological Consequences, Savanna C. Barry, A. Challen Hyman, Charles A. Jacoby, Laura K. Reynolds, Mark Kowalewski, Thomas K. Frazer
Variation In Seagrass-Associated Macroinvertebrate Communities Along The Gulf Coast Of Peninsular Florida: An Exploration Of Patterns And Ecological Consequences, Savanna C. Barry, A. Challen Hyman, Charles A. Jacoby, Laura K. Reynolds, Mark Kowalewski, Thomas K. Frazer
VIMS Articles
Seagrasses form vast meadows of structurally complex habitat that support faunal communities with greater numbers of species and individuals than nearby unstructured habitats. The Gulf coast of peninsular Florida represents a natural laboratory ideally suited to the study of processes that shape seagrass-associated invertebrate and fish communities within meadows of a single species of seagrass, Thalassia testudinum. This suitability arises from a pronounced structural and chemical gradient that exists over ecologically relevant spatial and temporal scales, as revealed by extensive monitoring of water quality and seagrass. We hypothesized that seagrass-associated invertebrate communities would vary across five estuarine systems spread …
Spatiotemporal Distribution Of Phycotoxins And Their Co-Occurrence Within Nearshore Waters, Michelle D. Onofrio, Todd A. Egerton, Kimberly S. Reece, Sarah K.D. Pease, Marta P. Sanderson, William Jones Iii, Evan Yeargan, Amanda Roach, Caroline Dement, William G. Reay, Allen R. Place, Juliette L. Smith
Spatiotemporal Distribution Of Phycotoxins And Their Co-Occurrence Within Nearshore Waters, Michelle D. Onofrio, Todd A. Egerton, Kimberly S. Reece, Sarah K.D. Pease, Marta P. Sanderson, William Jones Iii, Evan Yeargan, Amanda Roach, Caroline Dement, William G. Reay, Allen R. Place, Juliette L. Smith
VIMS Articles
Harmful algal blooms (HABs), varying in intensity and causative species, have historically occurred throughout the Chesapeake Bay, U.S.; however, phycotoxin data are sparse. The spatiotemporal distribution of phycotoxins was investigated using solid-phase adsorption toxin tracking (SPATT) across 12 shallow, nearshore sites within the lower Chesapeake Bay and Virginia's coastal bays over one year (2017-2018). Eight toxins, azaspiracid-1 (AZA1), azaspiracid-2 (AZA2), microcystin-LR (MC-LR), domoic acid (DA), okadaic acid (OA), dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2), and goniodomin A (GDA) were detected in SPATT extracts. Temporally, phycotoxins were always present in the region, with at least one phycotoxin group (i.e., consisting of OA and …
Krill Availability In Adjacent Adélie And Gentoo Penguin Foraging Regions Near Palmer Station, Antarctica, Schuyler C. Nardelli, Megan A. Cimino, John A. Conroy, William R. Fraser, Deborah K. Steinberg, Oscar Schofield
Krill Availability In Adjacent Adélie And Gentoo Penguin Foraging Regions Near Palmer Station, Antarctica, Schuyler C. Nardelli, Megan A. Cimino, John A. Conroy, William R. Fraser, Deborah K. Steinberg, Oscar Schofield
VIMS Articles
The Palmer Deep canyon along the West Antarctic Peninsula is a biological hotspot with abundant phytoplankton and krill supporting Adélie and gentoo penguin rookeries at the canyon head. Nearshore studies have focused on physical mechanisms driving primary production and penguin foraging, but less is known about finer-scale krill distribution and density. We designed two acoustic survey grids paired with conductivity–temperature–depth profiles within adjacent Adélie and gentoo penguin foraging regions near Palmer Station, Ant-arctica. The grids were sampled from January to March 2019 to assess variability in krill availability and associations with oceanographic properties. Krill density was similar in the two …
Cloud Shadows Drive Vertical Migrations Of Deep-Dwelling Marine Life, Melissa Omand, Deborah K. Steinberg, Karen Stamieszkin
Cloud Shadows Drive Vertical Migrations Of Deep-Dwelling Marine Life, Melissa Omand, Deborah K. Steinberg, Karen Stamieszkin
VIMS Articles
Our study provides evidence that, in addition to diel vertical migration, zooplankton residing at >300-m depth during the day perform high-frequency, vertical migrations due to light modulation by clouds. Using a water-following framework and measurements and modeling of the twilight zone light field, we isolated the detailed phototactic response and show that some twilight zone animals are considerably more active than previously thought, with a cumulative distance traveled of more than one-third of that for diel migration. The increased movement increases predation risk and has implications for the metabolic requirements of these animals in the food-limited deep sea.
Seagrass Recovery Following Marine Heat Wave Influences Sediment Carbon Stocks, Lillian R. Aoki, Karen J. Mcglathery, Patricia L. Wiberg, Matthew P. J. Oreska, Amelie C. Berger, Peter Berg, Robert J. Orth
Seagrass Recovery Following Marine Heat Wave Influences Sediment Carbon Stocks, Lillian R. Aoki, Karen J. Mcglathery, Patricia L. Wiberg, Matthew P. J. Oreska, Amelie C. Berger, Peter Berg, Robert J. Orth
VIMS Articles
Worldwide, seagrass meadows accumulate significant stocks of organic carbon (C),known as “blue” carbon, which can remain buried for decades to centuries. However,when seagrass meadows are disturbed, these C stocks may be remineralized, leading to significant CO2 emissions. Increasing ocean temperatures, and increasing frequency and severity of heat waves, threaten seagrass meadows and their sediment blue C. To date, no study has directly measured the impact of seagrass declines from high temperatures on sediment C stocks. Here, we use a long-term record of sediment C stocks from a 7-km2, restored eelgrass (Zostera marina) meadow to show that seagrass dieback following a …
Toward A Better Understanding Of Fish‐Based Contribution To Ocean Carbon Flux, Grace K. Saba, Adrian B. Burd, John P. Dunne, (...), Deborah K. Steinberg, Et Al
Toward A Better Understanding Of Fish‐Based Contribution To Ocean Carbon Flux, Grace K. Saba, Adrian B. Burd, John P. Dunne, (...), Deborah K. Steinberg, Et Al
VIMS Articles
Fishes are the dominant vertebrates in the ocean, yet we know little of their contribution to carbon export flux at regional to global scales. We synthesize the existing information on fish‐based carbon flux in coastal and pelagic waters, identify gaps and challenges in measuring this flux and approaches to address them, and recommend research priorities. Based on our synthesis of passive (fecal pellet sinking) and active (migratory) flux of fishes, we estimated that fishes contribute an average (± standard deviation) of about 16.1% (± 13%) to total carbon flux out of the euphotic zone. Using the mean value of model‐generated …
Saved By The Shell: Oyster Reefs Can Shield Juvenile Blue Crabs Callinectes Sapidus, Katherine S. Longmire, Rochelle D. Seitz, Alison Smith, Romuald N. Lipcius
Saved By The Shell: Oyster Reefs Can Shield Juvenile Blue Crabs Callinectes Sapidus, Katherine S. Longmire, Rochelle D. Seitz, Alison Smith, Romuald N. Lipcius
VIMS Articles
Juvenile blue crabs Callinectes sapidus use seagrass and other structured habitats as refuges from predation. Oyster reef habitats provide structural complexity that may offer refuge, but the value of these habitats for juvenile blue crabs has not been examined. We quantified survival of juvenile C. sapidus in structured oyster reef habitat versus unstructured soft-bottom habitat. In a field tethering experiment in the York River, lower Chesapeake Bay (USA), juvenile C.sapidus (10−50 mm carapace width [CW]) were tethered in sand (n = 40) or oyster reef (n = 39)habitats at subtidal sites 1−2 m deep. An underwater camera system was used …
Wap-1d-Var V1.0: Development And Evaluation Of A One-Dimensional Variational Data Assimilation Model For The Marine Ecosystem Along The West Antarctic Peninsula, Hyewon Heather Kim, Ya-Wei Luo, Hugh W. Ducklow, Oscar M. Schofield, Deborah K. Steinberg, Scott C. Doney
Wap-1d-Var V1.0: Development And Evaluation Of A One-Dimensional Variational Data Assimilation Model For The Marine Ecosystem Along The West Antarctic Peninsula, Hyewon Heather Kim, Ya-Wei Luo, Hugh W. Ducklow, Oscar M. Schofield, Deborah K. Steinberg, Scott C. Doney
VIMS Articles
The West Antarctic Peninsula (WAP) is a rapidlywarming region, with substantial ecological and biogeochemical responses to the observed change and variability for the past decades, revealed by multidecadal observations
from the Palmer Antarctica Long-Term Ecological Research (LTER) program. The wealth of these long-term observations provides an important resource for ecosystem modeling, but there has been a lack of focus on the development of numerical models that simulate time-evolving plankton dynamics over the austral growth season along the coastal WAP. Here, we introduce a one dimensional variational data assimilation planktonic ecosystem model (i.e., the WAP-1D-VAR v1.0 model) equipped with a model …
Distinguishing Zooplankton Fecal Pellets As A Component Of The Biological Pump Using Compound-Specific Isotope Analysis Of Amino Acids, S. C. Doherty, A. E. Maas, Deborah K. Steinberg, B. N. Popp, H. G. Close
Distinguishing Zooplankton Fecal Pellets As A Component Of The Biological Pump Using Compound-Specific Isotope Analysis Of Amino Acids, S. C. Doherty, A. E. Maas, Deborah K. Steinberg, B. N. Popp, H. G. Close
VIMS Articles
Zooplankton contribute a major component of the vertical flux of particulate organic matter to the ocean interior by packaging consumed food and waste into large, dense fecal pellets that sink quickly. Existing methods for quantifying the contribution of fecal pellets to particulate organic matter use either visual identification or lipid biomarkers, but these methods may exclude fecal material that is not morphologically distinct, or may include zooplankton carcasses in addition to fecal pellets. Based on results from seven pairs of wild-caught zooplankton and their fecal pellets, we assess the ability of compound-specific isotope analysis of amino acids (CSIA-AA) to chemically …
Role Of Food Web Interactions In Promoting Resilience To Nutrient Enrichment In A Brackish Water Eelgrass (Zostera Marina) Ecosystem, K. Gagnon, C. Gustafsson, (...), J. P. Richardson, P. L. Reynolds, J. E. Duffy, C. Boström
Role Of Food Web Interactions In Promoting Resilience To Nutrient Enrichment In A Brackish Water Eelgrass (Zostera Marina) Ecosystem, K. Gagnon, C. Gustafsson, (...), J. P. Richardson, P. L. Reynolds, J. E. Duffy, C. Boström
VIMS Articles
Understanding the ecological interactions that enhance the resilience of threatened ecosystems is essential in assuring their conservation and restoration. Top-down trophic interactions can increase resilience to bottom-up nutrient enrichment, however, as many seagrass ecosystems are threatened by both eutrophication and trophic modifications, understanding how these processes interact is important. Using a combination of approaches, we explored how bottom-up and top-down processes, acting individually or in conjunction, can affect eelgrass meadows and associated communities in the northern Baltic Sea. Field surveys along with fish diet and stable isotope analyses revealed that the eelgrass trophic network included two main top predatory fish …
Molecular Underpinnings And Biogeochemical Consequences Of Enhanced Diatom Growth In A Warming Southern Ocean, L.J. Jabre, A.E Allen, S.J.P. Mccain, (...), Rachel E. Sipler, Et Al
Molecular Underpinnings And Biogeochemical Consequences Of Enhanced Diatom Growth In A Warming Southern Ocean, L.J. Jabre, A.E Allen, S.J.P. Mccain, (...), Rachel E. Sipler, Et Al
VIMS Articles
Phytoplankton contribute to the Southern Ocean’s (SO) ability to absorb atmospheric CO2 and shape the stoichiometry of northward macronutrient delivery. Climate change is altering the SO environment, yet we know little about how resident phytoplankton will react to these changes. Here, we studied a natural SO community and compared responses of two prevalent, bloom-forming diatom groups to changes in temperature and iron that are projected to occur by 2100 to 2300. We found that one group, Pseudo-nitzschia, grows better under warmer low-iron conditions by managing cellular iron demand and efficiently increasing photosynthetic capacity. This ability to grow and …
Effect Of Environmental History On The Physiology And Acute Stress Response Of The Eastern Oyster Crassostrea Virginica, Jill Ashey, Emily B. Rivest
Effect Of Environmental History On The Physiology And Acute Stress Response Of The Eastern Oyster Crassostrea Virginica, Jill Ashey, Emily B. Rivest
VIMS Articles
Environmental history (regimes of water quality to which an organism has been exposed in the past) may influence how the physiology of eastern oysters Crassostrea virginica responds to future environmental conditions caused by climate change. Previous research has examined environmental history in a 1-dimensional framework, failing to capture environmental history complexity through space and time. In this study, we examined environmental history as a multi-faceted parameter, incorporating abiotic water quality components, such as temperature, pH, and salinity, that differ among locations. We also assessed how different lengths of environmental histories, defined as proximal and distal, affected oyster physiology and stress …
A Review Of How We Assess Denitrification In Oyster Habitats And Proposed Guidelines For Future Studies, Nicholas E. Ray, Boze Hancock, Mark J. Brush, Allison Colden, (...), M. Lisa Kellogg, Et Al
A Review Of How We Assess Denitrification In Oyster Habitats And Proposed Guidelines For Future Studies, Nicholas E. Ray, Boze Hancock, Mark J. Brush, Allison Colden, (...), M. Lisa Kellogg, Et Al
VIMS Articles
Excess nitrogen (N) loading and resulting eutrophication plague coastal ecosystems globally. Much work is being done to remove N before it enters coastal receiving waters, yet these efforts are not enough. Novel techniques to remove N from within the coastal ecosystem are now being explored. One of these techniques involves using oysters and their habitats to remove N via denitrification. There is substantial interest in incorporating oyster-mediated enhancement of benthic denitrification into N management plans and trading schemes. Measuring denitrification, however, is expensive and time consuming. For large-scale adoption of oyster-mediated denitrification into nutrient management plans, we need an accurate …
Seabed Resuspension In The Chesapeake Bay: Implications For Biogeochemical Cycling And Hypoxia, Julia M. Moriarty, Marjorie A.M. Friedrichs, Courtney K. Harris
Seabed Resuspension In The Chesapeake Bay: Implications For Biogeochemical Cycling And Hypoxia, Julia M. Moriarty, Marjorie A.M. Friedrichs, Courtney K. Harris
VIMS Articles
Sediment processes, including resuspension and transport, affect water quality in estuaries by altering light attenuation, primary productivity, and organic matter remineralization, which then influence oxygen and nitrogen dynamics. The relative importance of these processes on oxygen and nitrogen dynamics varies in space and time due to multiple factors and is difficult to measure, however, motivating a modeling approach to quantify how sediment resuspension and transport affect estuarine biogeochemistry. Results from a coupled hydrodynamic-sediment transport-biogeochemical model of the Chesapeake Bay for the summers of 2002 and 2003 showed that resuspension increased light attenuation, especially in the northernmost portion of the Bay, …
Multi-Scale Biodiversity Drives Temporal Variability In Macrosystems, Christopher J. Patrick, Kevin E. Mccluney, Albert Ruhi, Andrew Gregory, John Sabo, James H. Thorp
Multi-Scale Biodiversity Drives Temporal Variability In Macrosystems, Christopher J. Patrick, Kevin E. Mccluney, Albert Ruhi, Andrew Gregory, John Sabo, James H. Thorp
VIMS Articles
High temporal variability in environmental conditions, populations, and ecological communities can result in species extinctions and outbreaks of agricultural pests and disease vectors, as well as impact industries dependent on reliable provisioning of ecosys- tem services. Yet few empirical studies have focused on testing hypotheses about the drivers of ecological temporal variability at large spatial and temporal scales. Using decadal datasets that span aquatic and terrestrial macrosystems and structural equation modeling, we show that local temporal variability and spatial synchrony increase temporal variability for entire macrosystems. These mechanisms are influenced by environmental heterogeneity, habitat-level species diversity, spatial scale, and the …
Opportunities And Challenges For Including Oyster-Mediated Denitrification In Nitrogen Management Plans, Julie M. Rose, J. Stephen Gosnel, Suzanne Bricker, Mark J. Brush, Allison Colden, Et Al
Opportunities And Challenges For Including Oyster-Mediated Denitrification In Nitrogen Management Plans, Julie M. Rose, J. Stephen Gosnel, Suzanne Bricker, Mark J. Brush, Allison Colden, Et Al
VIMS Articles
Nitrogen pollution is one of the primary threats to coastal water quality globally, and governmental regulations and marine policy are increasingly requiring nitrogen remediation in management programs. Traditional mitigation strategies (e.g., advanced wastewater treatment) are not always enough to meet reduction goals. Novel opportunities for additional nitrogen reduction are needed to develop a portfolio of long-term solutions. Increasingly, in situ nitrogen reduction practices are providing a complementary management approach to the traditional source control and treatment, including recognition of potential contributions of coastal bivalve shellfish. While policy interest in bivalves has focused primarily on nitrogen removal via biomass harvest, bivalves …
A Global Analysis Of Complexity–Biodiversity Relationships On Marine Artificial Structures, Elisabeth M. A. Strain, Peter D. Steinberg, Maria Vozzo, (...), Kathleen E. Knick, Rochelle D. Seitz, Et Al
A Global Analysis Of Complexity–Biodiversity Relationships On Marine Artificial Structures, Elisabeth M. A. Strain, Peter D. Steinberg, Maria Vozzo, (...), Kathleen E. Knick, Rochelle D. Seitz, Et Al
VIMS Articles
Topographic complexity is widely accepted as a key driver of biodiversity, but at the patch-scale, complexity–biodiversity relationships may vary spatially and temporally according to the environmental stressors complexity mitigates, and the species richness and identity of potential colonists. Using a manipulative experiment, we assessed spatial variation in patch-scale effects of complexity on intertidal biodiversity.
An Operational Overview Of The Export Processes In The Ocean From Remote Sensing (Exports) Northeast Pacific Field Deployment, David A. Siegel, Ivona Cetinic, (...), Deborah K. Steinberg, Et Al
An Operational Overview Of The Export Processes In The Ocean From Remote Sensing (Exports) Northeast Pacific Field Deployment, David A. Siegel, Ivona Cetinic, (...), Deborah K. Steinberg, Et Al
VIMS Articles
The goal of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) field campaign is to develop a predictive understanding of the export, fate, and carbon cycle impacts of global ocean net primary production. To accomplish this goal, observations of export flux pathways, plankton community composition, food web processes, and optical, physical, and biogeochemical (BGC) properties are needed over a range of ecosystem states. Here we introduce the first EXPORTS field deployment to Ocean Station Papa in the Northeast Pacific Ocean during summer of 2018, providing context for other papers in this special collection. The experiment was conducted with …
An Ecosystem Is Not A Monument, And Other Challenges To Fishing In The 21st Century, Roger Mann
An Ecosystem Is Not A Monument, And Other Challenges To Fishing In The 21st Century, Roger Mann
VIMS Articles
The continental shelf of the United States was once the preserve of commercial fishermen. This is no longer the case. The exclusive economic zone is increasingly becoming the focus of other economically powerful, sometimes incompatible uses, including green energy, shipping, communications, mining, military exclusion zones, and conservation regions. These other uses generally have fixed boundaries. The distribution of fished species moves in relation to warming of shelf waters, presenting challenges to both federal regional fishery management councils and industry alike. There is need for continued engagement between user groups with respectful use of guiding science and legal structure to ensure …
Advancing The Sea Ice Hypothesis: Trophic Interactions Among Breeding Pygoscelis Penguins With Divergent Population Trends Throughout The Western Antarctic Peninsula, Kristen B. Gorman, Kate E. Ruck, Tony D. Williams, William R. Fraser
Advancing The Sea Ice Hypothesis: Trophic Interactions Among Breeding Pygoscelis Penguins With Divergent Population Trends Throughout The Western Antarctic Peninsula, Kristen B. Gorman, Kate E. Ruck, Tony D. Williams, William R. Fraser
VIMS Articles
We evaluated annual and regional variation in the dietary niche of Pygoscelis penguins including the sea ice-obligate Adélie penguin (Pygoscelis adeliae), and sea ice-intolerant chinstrap (Pygoscelis antarcticus) and gentoo (Pygoscelis papua) penguins, three species that nest throughout the western Antarctic Peninsula (AP) to test the sea ice trophic interaction hypothesis, which posits that penguin breeding populations with divergent trends, i.e., declining or increasing, are reliant on differing food webs. Our study relies on values of naturally occurring carbon (13C/12C, δ13C) and nitrogen (15N/14N, δ15N) stable isotopes as integrated proxies of penguin food webs measured
over three years at three different …
Effects Of A Natural Precipitation Gradient On Fish And Macroinvertebrate Assemblages In Coastal Streams, Sean Kinard, Christopher J. Patrick, Fernando Carvallo
Effects Of A Natural Precipitation Gradient On Fish And Macroinvertebrate Assemblages In Coastal Streams, Sean Kinard, Christopher J. Patrick, Fernando Carvallo
VIMS Articles
Anthropogenic climate change is expected to increase the aridity of many regions of the world. Surface water ecosystems are particularly vulnerable to changes in the water-cycle and may suffer adverse impacts in affected regions. To enhance our understanding of how freshwater communities will respond to predicted shifts in water-cycle dynamics, we employed a space for time approach along a natural precipitation gradient on the Texas Coastal Prairie. In the spring of 2017, we conducted surveys of 10 USGS-gauged, wadeable streams spanning a semi-arid to sub-humid rainfall gradient; we measured nutrients, water chemistry, habitat characteristics, benthic macroinvertebrates, and fish communities. Fish …
Temporal And Spatial Variability Of Phytoplankton And Mixotrophs In A Temperate Estuary, Nicole C. Millette, Marcella Da Costa, Jordan W. Mora, Rebecca J. Gast
Temporal And Spatial Variability Of Phytoplankton And Mixotrophs In A Temperate Estuary, Nicole C. Millette, Marcella Da Costa, Jordan W. Mora, Rebecca J. Gast
VIMS Articles
A significant proportion of phototrophic species are known to be mixotrophs: cells that obtain nutrients through a combination of photosynthesis and prey ingestion. Current methods to estimate mixotroph abundance in situ are known to be limited in their ability to help identify conditions that favor mixotrophs over strict autotrophs. For the first time, we combine microscopic analysis of phototrophic taxa with immunoprecipitated bromodeoxyuridine (BrdU)labeled DNA amplicon sequencing to identify and quantify active and putative mixotrophs at 2 locations in a microtidal temperate estuary. We analyze these data to examine spatial and temporal variability of phytoplankton and mixotrophs. Microscopy-based phototrophic diversity …
Environmentally-Determined Production Frontiers And Lease Utilization In Virginia's Eastern Oyster Aquaculture Industry, Jennifer Beckensteiner, Andrew M. Scheld, Pierre St-Laurent, Marjorie A.M. Friedrichs, David M. Kaplan
Environmentally-Determined Production Frontiers And Lease Utilization In Virginia's Eastern Oyster Aquaculture Industry, Jennifer Beckensteiner, Andrew M. Scheld, Pierre St-Laurent, Marjorie A.M. Friedrichs, David M. Kaplan
VIMS Articles
During the last decade, oyster aquaculture has rebounded in Virginia and has been associated with an increase in subaqueous leased area. Production levels remain historically low, however, and many leases are thought to be underutilized. This study uses a novel approach leveraging high-resolution environmental data to evaluate lease utilization and identify constraints on aquaculture development. Stochastic Frontier Analysis (SFA) and Data Envelopment Analysis (DEA) were used to define environmentally-determined production frontiers, i.e. production possibilities based on empirical observations of aquaculture production, available space, and environmental conditions. Both methods estimated Lease Capacity Utilization (LCU, from 0 to 1) for leases producing …
Determinants Of Community Compositional Change Are Equally Affected By Global Change, Meghan L. Avolio, Kimberley J. Komatsu, (...), David S. Johnson, Et Al
Determinants Of Community Compositional Change Are Equally Affected By Global Change, Meghan L. Avolio, Kimberley J. Komatsu, (...), David S. Johnson, Et Al
VIMS Articles
Global change is impacting plant community composition, but the mechanisms underlying these changes are unclear. Using a dataset of 58 global change experiments, we tested the five fundamental mechanisms of community change: changes in evenness and richness, reordering, species gains and losses. We found 71% of communities were impacted by global change treatments, and 88% of communities that were exposed to two or more global change drivers were impacted. Further, all mechanisms of change were equally likely to be affected by global change treatments— species losses and changes in richness were just as common as species gains and reordering. We …