Spivak
Amanda C.
Spivak
Amanda C.
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ArticleShallow ponds are heterogeneous habitats within a temperate salt marsh ecosystem(John Wiley & Sons, 2017-06-15) Spivak, Amanda C. ; Gosselin, Kelsey M. ; Howard, Evan M. ; Mariotti, Giulio ; Forbrich, Inke ; Stanley, Rachel H. R. ; Sylva, Sean P.Integrating spatial heterogeneity into assessments of salt marsh biogeochemistry is becoming increasingly important because disturbances that reduce plant productivity and soil drainage may contribute to an expansion of shallow ponds. These permanently inundated and sometimes prominent landscape features can exist for decades, yet little is known about pond biogeochemistry or their role in marsh ecosystem functioning. We characterized three ponds in a temperate salt marsh (MA, USA) over alternating periods of tidal isolation and flushing, during summer and fall, by evaluating the composition of plant communities and organic matter pools and measuring surface water oxygen, temperature, and conductivity. The ponds were located in the high marsh and had similar depths, temperatures, and salinities. Despite this, they had different levels of suspended particulate, dissolved, and sediment organic matter and abundances of phytoplankton, macroalgae, and Ruppia maritima. Differences in plant communities were reflected in pond metabolism rates, which ranged from autotrophic to heterotrophic. Integrating ponds into landcover-based estimates of marsh metabolism resulted in slower rates of net production (−8.1 ± 0.3 to −15.7 ± 0.9%) and respiration (−2.9 ± 0.5 to −10.0 ± 0.4%), compared to rates based on emergent grasses alone. Seasonality had a greater effect on pond water chemistry, organic matter pools, and algal abundances than tidal connectivity. Alternating stretches of tidal isolation and flushing did not affect pond salinities or algal communities, suggesting that exchange between ponds and nearby creeks was limited. Overall, we found that ponds are heterogeneous habitats and future expansion could reduce landscape connectivity and the ability of marshes to capture and store carbon.
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DatasetRamped pyrolysis oxidation (RPO) temperature and carbon dioxide evolved values of soils collected in 2014-2015 within Plum Island Ecosystems LTER(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2020-11-12) Spivak, AmandaRamped pyrolysis oxidation (RPO) temperature and carbon dioxide evolved values of soils at Plum Island Ecosystems - LTER. Data were collected 2014-2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/827427
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DatasetConcentrations of phospholipid-linked fatty acids (PLFAs) in the surface sediments of three marsh ponds in PIE-LTER (Rowley, MA) from 2014.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-07) Spivak, AmandaConcentrations of phospholipid-linked fatty acids (PLFAs) in the surface sediments of three marsh ponds in PIE-LTER (Rowley, MA). Data were collected over 11 weeks in the summer and fall of 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/738160
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DatasetBulk sediment organic matter composition of three marsh ponds in PIE-LTER (Rowley, MA) from 2014.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-07) Spivak, AmandaBulk sediment organic matter composition of three high marsh ponds within PIE-LTER. Data were collected over 11 weeks in the summer and fall of 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/738169
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DatasetFourier Transform Infrared Spectroscopy raw spectra of soils collected in 2014-2015 within Plum Island Ecosystems LTER(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2020-11-12) Spivak, AmandaBulk soil and elemental properties of marsh and infilled pond soils within Plum Island Ecosystems - LTER. Bulk soil properties of the soils are complemented with Fourier Transform Infrared Spectroscopy and ramped pyrolysis oxidation measurements of the soils. Data were collected during 2014-2015. This dataset includes the Fourier Transform Infrared Spectroscopy raw spectra. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/827452
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DatasetRamped pyrolysis oxidation (RPO) C isotope values of soils collected in 2014-2015 within Plum Island Ecosystems LTER(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2020-11-12) Spivak, AmandaRamped pyrolysis oxidation (RPO) C isotope values of soils at Plum Island Ecosystems - LTER. Data were collected 2014-2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/827365
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DatasetRaw concentrations of individual PLFA compounds from Massachusetts from 2012-2015.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-05) Spivak, AmandaRaw concentrations of individual PLFA compounds from Massachusetts from 2012-2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/669693
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ArticleProduction of two highly abundant 2-methyl-branched fatty acids by blooms of the globally significant marine cyanobacteria Trichodesmium erythraeum(American Chemical Society, 2021-08-26) Gosselin, Kelsey M. ; Nelson, Robert K. ; Spivak, Amanda C. ; Sylva, Sean P. ; Van Mooy, Benjamin A. S. ; Aeppli, Christoph ; Sharpless, Charles M. ; O’Neil, Gregory W. ; Arrington, Eleanor C. ; Reddy, Christopher M. ; Valentine, David L.The bloom-forming cyanobacteria Trichodesmium contribute up to 30% to the total fixed nitrogen in the global oceans and thereby drive substantial productivity. On an expedition in the Gulf of Mexico, we observed and sampled surface slicks, some of which included dense blooms of Trichodesmium erythraeum. These bloom samples contained abundant and atypical free fatty acids, identified here as 2-methyldecanoic acid and 2-methyldodecanoic acid. The high abundance and unusual branching pattern of these compounds suggest that they may play a specific role in this globally important organism.
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DatasetOrganic matter composition of the dominant plants in and around three marsh ponds in PIE-LTER (Rowley, MA) from 2014.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-07) Spivak, AmandaOrganic matter composition of the dominant plant communities in and around three high marsh ponds within PIE-LTER. Data were collected in the summer of 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/738188
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DatasetNoble gas concentrations and saturations from Marsh Pond in Massachusetts, USA from 2014.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-05) Stanley, Rachel ; Spivak, AmandaNoble gas concentrations and saturations from Marsh Pond in Massachusetts, USA from 2014. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/670694
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ArticleSoil organic carbon development and turnover in natural and disturbed salt marsh environments(American Geophysical Union, 2020-12-11) Luk, Sheron Y. ; Todd‐Brown, Katherine ; Eagle, Meagan ; McNichol, Ann P. ; Sanderman, Jonathan ; Gosselin, Kelsey M. ; Spivak, Amanda C.Salt marsh survival with sea‐level rise (SLR) increasingly relies on soil organic carbon (SOC) accumulation and preservation. Using a novel combination of geochemical approaches, we characterized fine SOC (≤1 mm) supporting marsh elevation maintenance. Overlaying thermal reactivity, source (δ13C), and age (F14C) information demonstrates several processes contributing to soil development: marsh grass production, redeposition of eroded material, and microbial reworking. Redeposition of old carbon, likely from creekbanks, represented ∼9%–17% of shallow SOC (≤26 cm). Soils stored marsh grass‐derived compounds with a range of reactivities that were reworked over centuries‐to‐millennia. Decomposition decreases SOC thermal reactivity throughout the soil column while the decades‐long disturbance of ponding accelerated this shift in surface horizons. Empirically derived estimates of SOC turnover based on geochemical composition spanned a wide range (640–9,951 years) and have the potential to inform predictions of marsh ecosystem evolution.
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PreprintAnimating the carbon cycle( 2013-08) Schmitz, Oswald J. ; Raymond, Peter A. ; Estes, James A. ; Kurz, Werner A. ; Holtgrieve, Gordon W. ; Ritchie, Mark E. ; Schindler, Daniel E. ; Spivak, Amanda C. ; Wilson, Rod W. ; Bradford, Mark A. ; Christensen, Villy ; Deegan, Linda A. ; Smetacek, Victor ; Vanni, Michael J. ; Wilmers, Christopher C.Understanding the biogeochemical processes regulating carbon cycling is central to mitigating atmospheric CO2 emissions. The role of living organisms has been accounted for, but the focus has traditionally been on contributions of plants and microbes. We develop the case that fully “animating” the carbon cycle requires broader consideration of the functional role of animals in mediating biogeochemical processes and quantification of their effects on carbon storage and exchange among terrestrial and aquatic reservoirs and the atmosphere. To encourage more hypothesis-driven experimental research that quantifies animal effects we discuss the mechanisms by which animals may affect carbon exchanges and storage within and among ecosystems and the atmosphere. We illustrate how those mechanisms lead to multiplier effects whose magnitudes may rival those of more traditional carbon storage and exchange rate estimates currently used in the carbon budget. Many animal species are already directly managed. Thus improved quantitative understanding of their influence on carbon budgets may create opportunity for management and policy to identify and implement new options for mitigating CO2 release at regional scales.
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ArticleSoil carbon consequences of historic hydrologic impairment and recent restoration in coastal wetlands(Association for the Sciences of Limnology and Oceanography, 2022-08-06) Eagle, Meagan ; Kroeger, Kevin D. ; Spivak, Amanda C. ; Wang, Faming ; Tang, Jianwu ; Abdul-Aziz, Omar I. ; Ishtiaq, Khandker S. ; O'Keefe Suttles, Jennifer A. ; Mann, Adrian G.Coastal wetlands provide key ecosystem services, including substantial long-term storage of atmospheric CO2 in soil organic carbon pools. This accumulation of soil organic matter is a vital component of elevation gain in coastal wetlands responding to sea-level rise. Anthropogenic activities that alter coastal wetland function through disruption of tidal exchange and wetland water levels are ubiquitous. This study assesses soil vertical accretion and organic carbon accretion across five coastal wetlands that experienced over a century of impounded hydrology, followed by restoration of tidal exchange 5 to 14 years prior to sampling. Nearby marshes that never experienced tidal impoundment served as controls with natural hydrology to assess the impact of impoundment and restoration. Dated soil cores indicate that elevation gain and carbon storage were suppressed 30–70 % during impoundment, accounting for the majority of elevation deficit between impacted and natural sites. Only one site had substantial subsidence, likely due to oxidation of soil organic matter. Vertical and carbon accretion gains were achieved at all restored sites, with carbon burial increasing from 96 ± 33 to 197 ± 64 g C m−2 y−1. The site with subsidence was able to accrete at double the rate (13 ± 5.6 mm y−1) of the natural complement, due predominantly to organic matter accumulation rather than mineral deposition, indicating these ecosystems are capable of large dynamic responses to restoration when conditions are optimized for vegetation growth. Hydrologic restoration enhanced elevation resilience and climate benefits of these coastal wetlands.
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ArticleCreated mangrove wetlands store belowground carbon and surface elevation change enables them to adjust to sea-level rise(Nature Publishing Group, 2017-04-21) Krauss, Ken W. ; Cormier, Nicole ; Osland, Michael J. ; Kirwan, Matthew L. ; Stagg, Camille L. ; Nestlerode, Janet A. ; Russell, Marc J. ; From, Andrew S. ; Spivak, Amanda C. ; Dantin, Darrin D. ; Harvey, James E. ; Almario, Alejandro E.Mangrove wetlands provide ecosystem services for millions of people, most prominently by providing storm protection, food and fodder. Mangrove wetlands are also valuable ecosystems for promoting carbon (C) sequestration and storage. However, loss of mangrove wetlands and these ecosystem services are a global concern, prompting the restoration and creation of mangrove wetlands as a potential solution. Here, we investigate soil surface elevation change, and its components, in created mangrove wetlands over a 25 year developmental gradient. All created mangrove wetlands were exceeding current relative sea-level rise rates (2.6 mm yr−1), with surface elevation change of 4.2–11.0 mm yr−1 compared with 1.5–7.2 mm yr−1 for nearby reference mangroves. While mangrove wetlands store C persistently in roots/soils, storage capacity is most valuable if maintained with future sea-level rise. Through empirical modeling, we discovered that properly designed creation projects may not only yield enhanced C storage, but also can facilitate wetland persistence perennially under current rates of sea-level rise and, for most sites, for over a century with projected medium accelerations in sea-level rise (IPCC RCP 6.0). Only the fastest projected accelerations in sea-level rise (IPCC RCP 8.5) led to widespread submergence and potential loss of stored C for created mangrove wetlands before 2100.
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ArticleEcosystem development after mangrove wetland creation : plant–soil change across a 20-year chronosequence(Springer, 2012-05-19) Osland, Michael J. ; Spivak, Amanda C. ; Nestlerode, Janet A. ; Lessmann, Jeannine M. ; Almario, Alejandro E. ; Heitmuller, Paul T. ; Russell, Marc J. ; Krauss, Ken W. ; Alvarez, Federico ; Dantin, Darrin D. ; Harvey, James E. ; From, Andrew S. ; Cormier, Nicole ; Stagg, Camille L.Mangrove wetland restoration and creation efforts are increasingly proposed as mechanisms to compensate for mangrove wetland losses. However, ecosystem development and functional equivalence in restored and created mangrove wetlands are poorly understood. We compared a 20-year chronosequence of created tidal wetland sites in Tampa Bay, Florida (USA) to natural reference mangrove wetlands. Across the chronosequence, our sites represent the succession from salt marsh to mangrove forest communities. Our results identify important soil and plant structural differences between the created and natural reference wetland sites; however, they also depict a positive developmental trajectory for the created wetland sites that reflects tightly coupled plant-soil development. Because upland soils and/or dredge spoils were used to create the new mangrove habitats, the soils at younger created sites and at lower depths (10–30 cm) had higher bulk densities, higher sand content, lower soil organic matter (SOM), lower total carbon (TC), and lower total nitrogen (TN) than did natural reference wetland soils. However, in the upper soil layer (0–10 cm), SOM, TC, and TN increased with created wetland site age simultaneously with mangrove forest growth. The rate of created wetland soil C accumulation was comparable to literature values for natural mangrove wetlands. Notably, the time to equivalence for the upper soil layer of created mangrove wetlands appears to be faster than for many other wetland ecosystem types. Collectively, our findings characterize the rate and trajectory of above- and below-ground changes associated with ecosystem development in created mangrove wetlands; this is valuable information for environmental managers planning to sustain existing mangrove wetlands or mitigate for mangrove wetland losses.
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ArticleSalt marsh pond biogeochemistry changes hourly-to-yearly but does not scale with dimensions or geospatial position(American Geophysical Union, 2020-09-15) Spivak, Amanda C. ; Denmark, Alexander ; Gosselin, Kelsey M. ; Sylva, Sean P.Shallow ponds are expanding in many salt marshes with potential impacts on ecosystem functioning. Determining how pond characteristics change over time and scale with physical dimensions and other spatial predictors could facilitate incorporation of ponds into projections of ecosystem change. We evaluated scaling relationships across six differently sized ponds in three regions of the high marshes within the Plum Island Ecosystems‐Long Term Ecological Research site (MA, USA). We further characterized diel fluctuations in surface water chemistry in two ponds to understand short‐term processes that affect emergent properties (e.g., habitat suitability). Primary producers drove oxygen levels to supersaturation during the day, while nighttime respiration resulted in hypoxic to anoxic conditions. Diel swings in oxygen were mirrored by pH and resulted in successive shifts in redox‐sensitive metabolisms, as indicated by nitrate consumption at dusk followed by peaks in ammonium and then sulfide overnight. Abundances of macroalgae and Ruppia maritima correlated with whole‐pond oxygen metabolism rates, but not with surface area (SA), volume (V), or SA:V. Moreover, there were no clear patterns in primary producer abundances, surface water chemistry, or pond metabolism rates across marsh regions supplied by different tidal creeks or that differed in distance to upland borders or creekbanks. Comparisons with data from 2 years prior demonstrate that plant communities and biogeochemical processes are not in steady state. Factors contributing to variability between ponds and years are unclear but likely include infrequent tidal exchange. Temporal and spatial variability and the absence of scaling relationships complicate the integration of high marsh ponds into ecosystem biogeochemical models.
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DatasetRaw benthic chlorophyll and phaeophytin data from cores collected in Massachusetts from 2012-2015.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-05) Spivak, AmandaRaw benthic chlorophyll and phaeophytin data from cores collected in Massachusetts from 2012-2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/669652
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DatasetDeployment history of sensors recording dissolved oxygen from Massachusetts from 2012.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-05) Spivak, AmandaDeployment history of sensors recording dissolved oxygen from Massachusetts from 2012. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/669673
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DatasetBulk soil and elemental properties of marsh and infilled pond soils collected in 2014-2015 within Plum Island Ecosystems LTER(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2020-11-13) Spivak, AmandaBulk soil and elemental properties of marsh and infilled pond soils within Plum Island Ecosystems - LTER. Data were collected 2014-2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/827298
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DatasetPAR data from stable isotope experiments conducted in Massachusetts from 2012.(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-05) Spivak, AmandaPAR data from stable isotope experiments conducted in Massachusetts from 2012. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/669741