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Full-Text Articles in Life Sciences
Structure And Functional Composition Of Macroinvertebrate Communities In Coastal Plain Streams Across A Precipitation Gradient, Fernando R. Carvallo, Bradley A. Strickland, Sean K. Kinard, Brandi Kiel Reese, James Derek Hogan, Christopher J. Patrick
Structure And Functional Composition Of Macroinvertebrate Communities In Coastal Plain Streams Across A Precipitation Gradient, Fernando R. Carvallo, Bradley A. Strickland, Sean K. Kinard, Brandi Kiel Reese, James Derek Hogan, Christopher J. Patrick
VIMS Articles
Climate change is expected to alter rainfall and temperature regimes across the world. The hydrology and riparian zone vegetation of lotic ecosystems are tightly linked to rainfall and a mechanistic understanding of the effects of rainfall on lotic ecosystems is needed to forecast the ecological impacts of climate change. However, it is difficult to isolate rainfall effects from other environmental variables that covary across climates. To address this, we leveraged a unique steep rainfall gradient with few covarying changes in elevation, temperature, and geology to evaluate the effects of rainfall on stream invertebrate communities. We surveyed nine streams in the …
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 …
Ecological Associations Of Littoraria Irrorata With Spartina Cynosuroides And Spartina Alterniflora, Caroline Mackenzie Failon, Serina Sebilian Wittyngham, David S. Johnson
Ecological Associations Of Littoraria Irrorata With Spartina Cynosuroides And Spartina Alterniflora, Caroline Mackenzie Failon, Serina Sebilian Wittyngham, David S. Johnson
VIMS Articles
It is well-documented that marsh periwinkles (Littoraria irrorata) consume and inhabit smooth cordgrass (Spartina alterniflora), but their interactions with big cordgrass (Spartina cynosuroides) remain unknown. Plant communities in mesohaline marshes will change as sea-level rise shifts species from salt-intolerant (e.g., S. cynosuroides) plants to salt-tolerant (e.g., S. alterniflora) ones. Therefore, understanding how L. irrorata interacts with different habitats provides insight into this species’ generalist nature and allows us to predict the potential impacts of changing plant communities on L. irrorata. We show, for the first time, that L. irrorata inhabits, climbs, …
Fish Assemblage Change Following The Structural Restoration Of A Degraded Stream, Carl A. Favata, Anabela Maia, Manisha Pant, Vaskar Nepal
Fish Assemblage Change Following The Structural Restoration Of A Degraded Stream, Carl A. Favata, Anabela Maia, Manisha Pant, Vaskar Nepal
VIMS Articles
Decades of anthropogenic pressure have harmed riverscapes throughout North America by degrading habitats and water quality and can result in the extirpation of sensitive aquatic taxa. Local stream restoration projects have increased in frequency, but monitoring is still infrequent. In 2010, Kickapoo Creek in East Central Illinois was subjected to a stream restoration project that included implementation of artificial riffles, riprap, scouring keys, and riparian vegetation. We monitored the restoration efforts for 6years after the restoration through annual sampling efforts at restored and reference sites to determine changes in habitat and fish assemblage using standard habitat sampling and electrofishing techniques. …
Differential Effects Of Bivalves On Sediment Nitrogen Cycling In A Shallow Coastal Bay, Ashley Smyth, Anna E. Murphy, Iris C. Anderson, Bk Song
Differential Effects Of Bivalves On Sediment Nitrogen Cycling In A Shallow Coastal Bay, Ashley Smyth, Anna E. Murphy, Iris C. Anderson, Bk Song
VIMS Articles
In coastal ecosystems, suspension-feeding bivalves can remove nitrogen though uptake and assimilation or enhanced denitrification. Bivalves may also retain nitrogen through increased mineralization and dissimilatory nitrate reduction to ammonium (DNRA). This study investigated the effects of oyster reefs and clam aquaculture on denitrification, DNRA, and nutrient fluxes (NOx, NH4 6 +, O2). Core incubations were conducted seasonally on sediments adjacent to restored oyster reefs (Crassostrea virginica), clam aquaculture beds (Mercenaria mercenaria) which contained live clams, and bare sediments from Smith Island Bay, Virginia, USA. Denitrification was significantly higher at oyster reef sediments and clam aquaculture site than bare sediment in …
Global Patterns In The Impact Of Marine Herbivores On Benthic Primary Producers, Alistair G.B. Poore, Alexandra H. Campbell, Ross Coleman, Graham J. Edgar, Veijo Jormalainen, Pamela L. Reynolds, Erik E. Sotka, John J. Stachowicz, Richard Taylor, Mathew A. Vanderklift, J. Emmett Duffy
Global Patterns In The Impact Of Marine Herbivores On Benthic Primary Producers, Alistair G.B. Poore, Alexandra H. Campbell, Ross Coleman, Graham J. Edgar, Veijo Jormalainen, Pamela L. Reynolds, Erik E. Sotka, John J. Stachowicz, Richard Taylor, Mathew A. Vanderklift, J. Emmett Duffy
VIMS Articles
Despite the importance of consumers in structuring communities, and the widespread assumption that consumption is strongest at low latitudes, empirical tests for global scale patterns in the magnitude of consumer impacts are limited. In marine systems, the long tradition of experimentally excluding herbivores in their natural environments allows consumer impacts to be quantified on global scales using consistent methodology. We present a quantitative synthesis of 613 marine herbivore exclusion experiments to test the influence of consumer traits, producer traits and the environment on the strength of herbivore impacts on benthic producers. Across the globe, marine herbivores profoundly reduced producer abundance …
The Functional Role Of Producer Diversity In Ecosystems, Bradley J. Cardinale, Kristin L. Matulich, David U. Hooper, Jarrett E. K. Byrnes, Emmett J. Duffy, Lars Gamfeldt, Patricia Balvanera, Mary I. O'Connor, Andrew Gonzalez
The Functional Role Of Producer Diversity In Ecosystems, Bradley J. Cardinale, Kristin L. Matulich, David U. Hooper, Jarrett E. K. Byrnes, Emmett J. Duffy, Lars Gamfeldt, Patricia Balvanera, Mary I. O'Connor, Andrew Gonzalez
VIMS Articles
Over the past several decades, a rapidly expanding field of research known as biodiversity and ecosystem functioning has begun to quantify how the world's biological diversity can, as an independent variable, control ecological processes that are both essential for, and fundamental to, the functioning of ecosystems. Research in this area has often been justified on grounds that (1) loss of biological diversity ranks among the most pronounced changes to the global environment and that (2) reductions in diversity, and corresponding changes in species composition, could alter important services that ecosystems provide to humanity (e.g., food production, pest/disease control, water purification). …
Oyster Reefs At Risk And Recommendations For Conservation, Restoration, And Management, Michael W. Beck, Robert D. Brumbaugh, Laura Airoldi, Alvar Carranza, Loren D. Coen, Christine Crawford, Omar Defeo, Graham J. Edgar, Boze Handcock, Matthew C. Kay, Hunter S. Lenihan, Mark Luckenbach, Caitlyn L. Toropova, Guofan Zhang, Ximing Guo
Oyster Reefs At Risk And Recommendations For Conservation, Restoration, And Management, Michael W. Beck, Robert D. Brumbaugh, Laura Airoldi, Alvar Carranza, Loren D. Coen, Christine Crawford, Omar Defeo, Graham J. Edgar, Boze Handcock, Matthew C. Kay, Hunter S. Lenihan, Mark Luckenbach, Caitlyn L. Toropova, Guofan Zhang, Ximing Guo
VIMS Articles
Native oyster reefs once dominated many estuaries, ecologically and economically. Centuries of resource extraction exacerbated by coastal degradation have pushed oyster reefs to the brink of functional extinction worldwide. We examined the condition of oyster reefs across 144 bays and 44 ecoregions; our comparisons of past with present abundances indicate that more than 90% of them have been lost in bays (70%) and ecoregions (63%). In many bays, more than 99% of oyster reefs have been lost and are functionally extinct. Overall, we estimate that 85% of oyster reefs have been lost globally. Most of the world's remaining wild capture …
Accelerating Loss Of Seagrasses Across The Globe Threatens Coastal Ecosystems, Michelle Waycott, Carlos M. Duarte, Tim J. Carruthers, Robert J. Orth, Wc Dennison, Suzanne Olyarnik, Ainsley Calladine, James W. Fourqurean, Kl Heck, A. Randall Hughes, Gary A. Kendrick, W. Judson Kenworthy, Frederick T. Short, Susan L. Williams
Accelerating Loss Of Seagrasses Across The Globe Threatens Coastal Ecosystems, Michelle Waycott, Carlos M. Duarte, Tim J. Carruthers, Robert J. Orth, Wc Dennison, Suzanne Olyarnik, Ainsley Calladine, James W. Fourqurean, Kl Heck, A. Randall Hughes, Gary A. Kendrick, W. Judson Kenworthy, Frederick T. Short, Susan L. Williams
VIMS Articles
Coastal ecosystems and the services they provide are adversely affected by a wide variety of human activities. In particular, seagrass meadows are negatively affected by impacts accruing from the billion or more people who live within 50 km of them. Seagrass meadows provide important ecosystem services, including an estimated $1.9 trillion per year in the form of nutrient cycling; an order of magnitude enhancement of coral reef fish productivity; a habitat for thousands of fish, bird, and invertebrate species; and a major food source for endangered dugong, manatee, and green turtle. Although individual impacts from coastal development, degraded water quality, …
Bacterial Vs. Zooplankton Control Of Sinking Particle Flux In The Ocean's Twilight Zone, Deborah K. Steinberg, Benjamin A.S. Van Mooy, Ken O. Buesseler, Philip W. Boyd, Toru Kobari, David M. Karl
Bacterial Vs. Zooplankton Control Of Sinking Particle Flux In The Ocean's Twilight Zone, Deborah K. Steinberg, Benjamin A.S. Van Mooy, Ken O. Buesseler, Philip W. Boyd, Toru Kobari, David M. Karl
VIMS Articles
The downward flux of particulate organic carbon (POC) decreases significantly in the oceanÂs mesopelagic or ‘twilight’ zone due both to abiotic processes and metabolism by resident biota. Bacteria and zooplankton solubilize and consume POC to support their metabolism, but the relative importance of bacteria vs. zooplankton in the consumption of sinking particles in the twilight zone is unknown. We compared losses of sinking POC, using differences in export flux measured by neutrally buoyant sediment traps at a range of depths, with bacteria and zooplankton metabolic requirements at the Hawaii Ocean Time‐series station ALOHA in the subtropical Pacific and the Japanese …
The Charisma Of Coastal Ecosystems: Addressing The Imbalance, Carlos M. Duarte, Wc Dennison, Robert J. Orth, Tim J. Carruthers
The Charisma Of Coastal Ecosystems: Addressing The Imbalance, Carlos M. Duarte, Wc Dennison, Robert J. Orth, Tim J. Carruthers
VIMS Articles
Coastal ecosystems including coral reefs, mangrove forests, seagrass meadows, and salt marshes are being lost at alarming rates, and increased scientific understanding of causes has failed to stem these losses. Coastal habitats receive contrasting research effort, with 60% of all of the published research carried out on coral reefs, compared to 11–14% of the records for each of salt marshes, mangrove forests, and seagrass meadows. In addition, these highly connected and interdependent coastal ecosystems receive widely contrasting media attention that is disproportional to their scientific attention. Seagrass ecosystems receive the least attention in the media (1.3% of the media reports) …
The Functional Role Of Biodiversity In Ecosystems: Incorporating Trophic Complexity, J. Emmett Duffy, Bradley J. Cardinale, Kristin E. France, Peter B. Mcintyre, Elisa Thebault, Michel Loreau
The Functional Role Of Biodiversity In Ecosystems: Incorporating Trophic Complexity, J. Emmett Duffy, Bradley J. Cardinale, Kristin E. France, Peter B. Mcintyre, Elisa Thebault, Michel Loreau
VIMS Articles
Understanding how biodiversity affects functioning of ecosystems requires integrating diversity within trophic levels (horizontal diversity) and across trophic levels (vertical diversity, including food chain length and omnivory). We review theoretical and experimental progress toward this goal. Generally, experiments show that biomass and resource use increase similarly with horizontal diversity of either producers or consumers. Among prey, higher diversity often increases resistance to predation, due to increased probability of including inedible species and reduced efficiency of specialist predators confronted with diverse prey. Among predators, changing diversity can cascade to affect plant biomass, but the strength and sign of this effect depend …
Evaluation Of A Lifetime‐Based Optode To Measure Oxygen In Aquatic Systems, Anders Tengberg, Jostein Hovdenes, Henrik J. Andersson, Olivier Brocandel, Robert J. Diaz, David Hebert, Tony Arnerich, Christian Huber, Arne Kortzinger, Alexis Khripounoff, Francisco Rey, Christer Ronning, Jens Schimanski, Stefan Sommer, Achim Stangelmayer
Evaluation Of A Lifetime‐Based Optode To Measure Oxygen In Aquatic Systems, Anders Tengberg, Jostein Hovdenes, Henrik J. Andersson, Olivier Brocandel, Robert J. Diaz, David Hebert, Tony Arnerich, Christian Huber, Arne Kortzinger, Alexis Khripounoff, Francisco Rey, Christer Ronning, Jens Schimanski, Stefan Sommer, Achim Stangelmayer
VIMS Articles
In this article, we evaluate the performance of a commercially available lifetime‐based optode and compare it with data obtained by other methods. We performed a set of 10 different tests, including targeted laboratory evaluations and field studies, covering a wide range of situations from shallow coastal waters and wastewater treatment plants to abyssal depths. Our principal conclusion is that, owing to high accuracy (± 2 µM), long‐term stability (more than 20 months), lack of pressure hysteresis, and limited cross‐sensitivity, this method is overall more suitable for oxygen monitoring than other methods.
Allee Effects Driven By Predation, J Gascoigne, Rom Lipcius
Allee Effects Driven By Predation, J Gascoigne, Rom Lipcius
VIMS Articles
No abstract provided.
Abundance And Distribution Of Planktonic Archaea And Bacteria In The Waters West Of The Antarctic Peninsula, Matthew Church, Edward F. Delong, Hugh Ducklow, Markus Karner, Christian Preston, David M. Karl
Abundance And Distribution Of Planktonic Archaea And Bacteria In The Waters West Of The Antarctic Peninsula, Matthew Church, Edward F. Delong, Hugh Ducklow, Markus Karner, Christian Preston, David M. Karl
VIMS Articles
Polyribonucleotide probes targeting planktonic archaeal (Group I and II) and bacterial rRNA revealed that Archaea comprised a significant fraction of total prokaryote cell abundance in the marine waters west of the Antarctic Peninsula. Determinations of Archaea and Bacteria cell abundances were made during two research cruises to the Palmer Long‐Term Ecological Research region during the austral winter and summer of 1999. During the austral summer, surface water abundances of Group I (GI) Archaea were generally low, averaging 4.7 x 103 cells ml−1 and accounting for 1% of the total picoplankton assemblage. The abundance of GI Archaea increased significantly with depth, …
Biodiversity And Ecosystem Function: The Consumer Connection, J. Emmett Duffy
Biodiversity And Ecosystem Function: The Consumer Connection, J. Emmett Duffy
VIMS Articles
Proposed links between biodiversity and ecosystem processes have generated intense interest and controversy in recent years. With few exceptions, however, empirical studies have focused on grassland plants and laboratory aquatic microbial systems, whereas there has been little attention to how changing animal diversity may influence ecosystem processes. Meanwhile, a separate research tradition has demonstrated strong top‐down forcing in many systems, but has considered the role of diversity in these processes only tangentially. Integration of these research directions is necessary for more complete understanding in both areas. Several considerations suggest that changing diversity in multi‐level food webs can have important ecosystem …
Relative Strengths Of Competition For Space And Food In A Sessile Filter Feeder, David P. Lohse
Relative Strengths Of Competition For Space And Food In A Sessile Filter Feeder, David P. Lohse
VIMS Articles
Previous workers have demonstrated that sessile filter feeders compete for food and space, but little is known about the relative strengths of these two processes. To determine this, the density and position of barnacles (Balanus improvisus) in a unidirectional current were manipulated to alter the amount of competition for space and food, respectively. Results indicated that competition for space significantly reduced growth, and marginally reduced survivorship. Competition for food was also detected, but only among uncrowded individuals; thus, it appears to be the weaker of the two interactions. However, under crowded conditions, downstream individuals actually grew more than those upstream. …
Atmospheric Co2 Evasion, Dissolved Inorganic Carbon Production, And Net Heterotrophy In The York River Estuary, Peter Raymond, James E. Bauer, Jonathan Cole
Atmospheric Co2 Evasion, Dissolved Inorganic Carbon Production, And Net Heterotrophy In The York River Estuary, Peter Raymond, James E. Bauer, Jonathan Cole
VIMS Articles
Direct measurements of the partial pressure of CO2 (pCO2) and dissolved inorganic carbon (DIC) were made over a 2‐yr period in surface waters of the York River estuary in Virginia. The pCO2 in surface waters exceeded that in the overlying atmosphere, indicating that the estuary was a net source of CO2 to the atmosphere at most times and locations. Salinity‐based DIC mixing curves indicate there was also an internal source of both DIC and alkalinity, implying net alkalinity generation within the estuary. The DIC and alkalinity source displayed seasonal patterns similar to that of pCO2 and were reproducible over a …
Organic Carbon Partitioning During Spring Phytoplankton Blooms In The Ross Sea Polynya And The Sargasso Sea, C.A. Carlson, Hugh Ducklow, Da Hansell, Walker O. Smith Jr.
Organic Carbon Partitioning During Spring Phytoplankton Blooms In The Ross Sea Polynya And The Sargasso Sea, C.A. Carlson, Hugh Ducklow, Da Hansell, Walker O. Smith Jr.
VIMS Articles
In this study we evaluate the partitioning of organic carbon between the particulate and dissolved pools during spring phytoplankton blooms in the Ross Sea, Antarctica, and the Sargasso Sea. As part of a multidisciplinary project in the Ross Sea polynya we investigated the dynamics of the dissolved organic carbon (DOC) pool and the role it played in the carbon cycle during the 1994 spring phytoplankton bloom. Phytoplankton biomass during the bloom was dominated by an Antarctic Phaeocystis sp. We determined primary productivity (PP; via H14CO3, incubations), particulate organic carbon (POC), bacterial productivity (BP; via [3H]thymidine incorporation), and DOC during two …
Concentrations And Uptake Of Neutral Monosaccharides Along 14°W In The Equatorial Pacific: Contribution Of Glucose To Heterotrophic Bacterial Activity And The Dom Flux, James Rich, Hugh Ducklow, David L. Kirchman
Concentrations And Uptake Of Neutral Monosaccharides Along 14°W In The Equatorial Pacific: Contribution Of Glucose To Heterotrophic Bacterial Activity And The Dom Flux, James Rich, Hugh Ducklow, David L. Kirchman
VIMS Articles
We examined concentrations and uptake of dissolved neutral monosaccharides (DNMS) in order to determine the contribution of DNMS to heterotrophic bacterial production and to the flux of dissolved organic matler (DOM) in the equatorial Pacific. DNMS concentrations were greater during El Niño‐affected months of February–April 1992 than during August–October 1992; in contrast, glucose turnover was the opposite— turnover was faster in August–October than in February–April. The variation in sugar concentrations and turnover probably resulted from El Niño‐induced changes in primary production; as El Niño waned primary production increased, which appeared to stimulate bacterial activity, especially glucose turnover, that in turn …
The Magnitude And Persistence Of Soil No, N2o, Ch4, And Co, Fluxes From Burned Tropical Savanna In Brazil, M Poth, Iris C. Anderson, Et Al
The Magnitude And Persistence Of Soil No, N2o, Ch4, And Co, Fluxes From Burned Tropical Savanna In Brazil, M Poth, Iris C. Anderson, Et Al
VIMS Articles
Among all global ecosystems, tropical savannas are the most severely and extensively affected by anthropogenic burning. Frequency of fire in cerrado,a type of tropical savanna covering 25% of Brazil, is 2 to 4 years. In 1992 we measured soil fluxes of NO, N2O, CH4, and CO2 from cerrado sites that had been burned within the previous 2 days, 30 days, 1 year, and from a control site last burned in 1976. NO and N2O fluxes responded dramatically to fire with the highest fluxes observed from newly burned soils after addition of water. Emissions of N-trace gases after burning were of …
High Phytoplankton Growth And Production Rates In Oligotrophic Hawaiian Coastal Waters, E. A. Laws, Dg Redalje, Larry W. Haas, P. K. Bienfang, Rw Eppley, W. G. Harrison, David Karl, J. Marra
High Phytoplankton Growth And Production Rates In Oligotrophic Hawaiian Coastal Waters, E. A. Laws, Dg Redalje, Larry W. Haas, P. K. Bienfang, Rw Eppley, W. G. Harrison, David Karl, J. Marra
VIMS Articles
Plankton biomass, material fluxes, e.g. 14C uptake, and specific growth rates are related quantities. In the course of comparing various methods of measuring these properties in September 1982 off Oahu, Hawaii, we found specific growth rates of 1–2·d−1. Such rates approach the maximum expected values observed in laboratory cultures.