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Michael Rasheed - One of the best experts on this subject based on the ideXlab platform.
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green turtle chelonia mydas grazing plot formation creates structural changes in a multi species great barrier reef Seagrass Meadow
Marine Environmental Research, 2020Co-Authors: Abigail L. Scott, Paul H. York, Michael RasheedAbstract:The Great Barrier Reef (GBR) contains extensive Seagrass Meadows with abundant and diverse herbivore populations. Typically, Meadows in the region are multi-species and dominated by fast growing opportunistic Seagrass species. However, we know little about how herbivores modify these types of Seagrass Meadows by grazing. We conducted the first megaherbivore exclusion study in the GBR at Green Island (Queensland) to understand how green turtle grazing structures these multi-species tropical Seagrass Meadows. After excluding green turtles for three months, we found that grazing only impacted Seagrasses at one site, where green turtles created a grazing plot by actively feeding on both above and below ground Seagrass structures, a rare observation for the species. Within this grazing plot at the end of the experiment, the un-caged control treatments open to grazing had a 60% reduction in both above and below ground biomass, and shoot height was reduced by 75%, but there was no impact of grazing on the Seagrass species mix. Our study shows that grazing plot formation by green turtles occurs in GBR fast growing Seagrass communities and reduces both above and below ground Seagrass biomass, this behaviour may be targeting elevated leaf nutrients, or nutritional content of rhizomes. This study is the first documented case of grazing plot formation by green turtles in the GBR and suggests that grazing pressure has a major influence on Seagrass Meadow structure.
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using modis data for understanding changes in Seagrass Meadow health a case study in the great barrier reef australia
Marine Environmental Research, 2014Co-Authors: Caroline Petus, Michael Rasheed, Catherine J Collier, Michelle Devlin, S A MckennaAbstract:Stretching more than 2000 km along the Queensland coast, the Great Barrier Reef Marine Park (GBR) shelters over 43,000 square km of Seagrass Meadows. Despite the status of marine protected area and World Heritage listing of the GBR, local Seagrass Meadows are under stress from reduced water quality levels; with reduction in the amount of light available for Seagrass photosynthesis defined as the primary cause of Seagrass loss throughout the GBR. Methods have been developed to map GBR plume water types by using MODIS quasi-true colour (hereafter true colour) images reclassified in function of their dominant colour. These data can be used as an interpretative tool for understanding changes in Seagrass Meadow health (as defined in this study by the Seagrass area and abundance) at different spatial and temporal scales. We tested this method in Cleveland Bay, in the northern GBR, where substantial loss in Seagrass area and biomass was detected by annual monitoring from 2007 to 2011. A strong correlation was found between bay-wide Seagrass Meadow area and biomass and exposure to turbid Primary (sediment-dominated) water type. There was also a strong correlation between the changes of biomass and area of individual Meadows and exposure of Seagrass ecosystems to Primary water type over the 5-year period. Seagrass Meadows were also grouped according to the dominant species within each Meadow, irrespective of location within Cleveland Bay. These consolidated community types did not correlate well with the exposure to Primary water type, and this is likely to be due to local environmental conditions with the individual Meadows that comprise these groupings. This study proved that remote sensing data provide the synoptic window and repetitivity required to investigate changes in water quality conditions over time. Remote sensing data provide an opportunity to investigate the risk of marine-coastal ecosystems to light limitation due to increased water turbidity when in situ water quality data is not available or is insufficient.
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long term climate associated dynamics of a tropical Seagrass Meadow implications for the future
Marine Ecology Progress Series, 2011Co-Authors: Michael Rasheed, Richard K F UnsworthAbstract:The long-term changes of tropical intertidal Seagrass, mainly Halodule uninervis and Halophila ovalis Meadows and their relationship to climate are poorly documented. Developing a greater understanding of the effects of climate on Seagrass Meadows is critical for estimating the effects of future climate change scenarios. Here we document the temporal dynamics of coastal inter- tidal Seagrass in tropical northeast Australia over 16 yr of detailed monitoring. This study is the first to directly relate such change to long-term climate variability in the Indo-Pacific region and southern hemisphere. Regression modelling was used to relate Seagrass biomass and Meadow area measure- ments to climate data. The aboveground biomass and area of the Meadow were correlated with the interacting factors of air temperature, precipitation, daytime tidal exposure and freshwater runoff from nearby rivers. Elevated temperature and reduced flow from rivers were significantly correlated (R 2 = 0.6, p < 0.001) with periods of lower Seagrass biomass. Results of this study have important implications for the long-term viability of Seagrasses with regard to climate change scenarios. Mod- elling of our findings indicates that future higher temperatures could be detrimental to Indo-Pacific intertidal, coastal and estuarine Seagrass Meadows.
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recovery and succession in a multi species tropical Seagrass Meadow following experimental disturbance the role of sexual and asexual reproduction
Journal of Experimental Marine Biology and Ecology, 2004Co-Authors: Michael RasheedAbstract:Recolonisation and succession in a multi-species tropical Seagrass Meadow was examined by creating gaps (50×50 cm) in the Meadow and manipulating the supply of sexual and asexual propagules. Measurements of leaf shoot density and estimates of above-ground biomass were conducted monthly to measure recovery of gaps between September 1995 and November 1997. Measurements of the seeds stored in the sediment (seed bank) and horizontal rhizome growth of colonising species were also conducted to determine their role in the recovery process. Asexual colonisation through horizontal rhizome growth from the surrounding Meadow was the main mechanism for colonisation of gaps created in the Meadow. The seed bank played no role in recolonisation of cleared plots. Total shoot density and above-ground biomass (all species pooled) of cleared plots recovered asexually to the level of the undisturbed controls in 10 and 7 months, respectively. There was some sexual recruitment into cleared plots where asexual colonisation was prevented but Seagrass abundance (shoot density and biomass) did not reach the level of unmanipulated controls. Seagrass species did not appear to form seed banks despite some species being capable of producing long-lived seeds. The species composition of cleared plots remained different to the undisturbed controls throughout the 26-month experiment. Syringodium isoetifolium was a rapid asexual coloniser of disturbed plots and remained at higher abundances than in the control treatments for the duration of the study. S. isoetifolium had the fastest horizontal rhizome growth of species asexually colonising cleared plots (6.9 mm day−1). Halophila ovalis was the most successful sexual coloniser but was displaced by asexually colonising species. H. ovalis was the only species observed to produce fruits during the study. Small disturbances in the Meadow led to long-term (>2 years) changes in community composition. This study demonstrated that succession in tropical Seagrass communities was not a deterministic process. Variations in recovery observed for different tropical Seagrass communities highlighted the importance of understanding life history characteristics of species within individual communities to effectively predict their response to disturbance. A reproductive strategy involving clonal growth and production of long-lived, locally dispersed seeds is suggested which may provide an evolutionary advantage to plants growing in tropical environments subject to temporally unpredictable major disturbances such as cyclones.
Ken Caldeira - One of the best experts on this subject based on the ideXlab platform.
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expected limits on the ocean acidification buffering potential of a temperate Seagrass Meadow
Ecological Applications, 2018Co-Authors: David A Koweek, Kathryn Hewett, Brian Gaylord, Sarah N Giddings, Yuichiro Takeshita, Jennifer L Ruesink, Kerry J Nickols, John J Stachowicz, Richard C Zimmerman, Ken CaldeiraAbstract:Author(s): Koweek, David A; Zimmerman, Richard C; Hewett, Kathryn M; Gaylord, Brian; Giddings, Sarah N; Nickols, Kerry J; Ruesink, Jennifer L; Stachowicz, John J; Takeshita, Yuichiro; Caldeira, Ken | Abstract: Ocean acidification threatens many marine organisms, especially marine calcifiers. The only global-scale solution to ocean acidification remains rapid reduction in CO2 emissions. Nevertheless, interest in localized mitigation strategies has grown rapidly because of the recognized threat ocean acidification imposes on natural communities, including ones important to humans. Protection of Seagrass Meadows has been considered as a possible approach for localized mitigation of ocean acidification due to their large standing stocks of organic carbon and high productivity. Yet much work remains to constrain the magnitudes and timescales of potential buffering effects from Seagrasses. We developed a biogeochemical box model to better understand the potential for a temperate Seagrass Meadow to locally mitigate the effects of ocean acidification. Then we parameterized the model using data from Tomales Bay, an inlet on the coast of California, USA which supports a major oyster farming industry. We conducted a series of month-long model simulations to characterize processes that occur during summer and winter. We found that average pH in the Seagrass Meadows was typically within 0.04 units of the pH of the primary source waters into the Meadow, although we did find occasional periods (hours) when Seagrass metabolism may modify the pH by up to ±0.2 units. Tidal phasing relative to the diel cycle modulates localized pH buffering within the Seagrass Meadow such that maximum buffering occurs during periods of the year with midday low tides. Our model results suggest that Seagrass metabolism in Tomales Bay would not provide long-term ocean acidification mitigation. However, we emphasize that our model results may not hold in Meadows where assumptions about depth-averaged net production and seawater residence time within the Seagrass Meadow differ from our model assumptions. Our modeling approach provides a framework that is easily adaptable to other Seagrass Meadows in order to evaluate the extent of their individual buffering capacities. Regardless of their ability to buffer ocean acidification, Seagrass Meadows maintain many critically important ecosystem goods and services that will be increasingly important as humans increasingly affect coastal ecosystems.
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expected limits on the ocean acidification buffering potential of a temperate Seagrass Meadow
Ecological Applications, 2018Co-Authors: David A Koweek, Kathryn Hewett, Brian Gaylord, Sarah N Giddings, Yuichiro Takeshita, Jennifer L Ruesink, Kerry J Nickols, John J Stachowicz, Richard C Zimmerman, Ken CaldeiraAbstract:Ocean acidification threatens many marine organisms, especially marine calcifiers. The only global-scale solution to ocean acidification remains rapid reduction in CO2 emissions. Nevertheless, interest in localized mitigation strategies has grown rapidly because of the recognized threat ocean acidification imposes on natural communities, including ones important to humans. Protection of Seagrass Meadows has been considered as a possible approach for localized mitigation of ocean acidification due to their large standing stocks of organic carbon and high productivity. Yet much work remains to constrain the magnitudes and timescales of potential buffering effects from Seagrasses. We developed a biogeochemical box model to better understand the potential for a temperate Seagrass Meadow to locally mitigate the effects of ocean acidification. Then we parameterized the model using data from Tomales Bay, an inlet on the coast of California, USA which supports a major oyster farming industry. We conducted a series of month-long model simulations to characterize processes that occur during summer and winter. We found that average pH in the Seagrass Meadows was typically within 0.04 units of the pH of the primary source waters into the Meadow, although we did find occasional periods (hours) when Seagrass metabolism may modify the pH by up to ±0.2 units. Tidal phasing relative to the diel cycle modulates localized pH buffering within the Seagrass Meadow such that maximum buffering occurs during periods of the year with midday low tides. Our model results suggest that Seagrass metabolism in Tomales Bay would not provide long-term ocean acidification mitigation. However, we emphasize that our model results may not hold in Meadows where assumptions about depth-averaged net production and seawater residence time within the Seagrass Meadow differ from our model assumptions. Our modeling approach provides a framework that is easily adaptable to other Seagrass Meadows in order to evaluate the extent of their individual buffering capacities. Regardless of their ability to buffer ocean acidification, Seagrass Meadows maintain many critically important ecosystem goods and services that will be increasingly important as humans increasingly affect coastal ecosystems.
Abigail L. Scott - One of the best experts on this subject based on the ideXlab platform.
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green turtle chelonia mydas grazing plot formation creates structural changes in a multi species great barrier reef Seagrass Meadow
Marine Environmental Research, 2020Co-Authors: Abigail L. Scott, Paul H. York, Michael RasheedAbstract:The Great Barrier Reef (GBR) contains extensive Seagrass Meadows with abundant and diverse herbivore populations. Typically, Meadows in the region are multi-species and dominated by fast growing opportunistic Seagrass species. However, we know little about how herbivores modify these types of Seagrass Meadows by grazing. We conducted the first megaherbivore exclusion study in the GBR at Green Island (Queensland) to understand how green turtle grazing structures these multi-species tropical Seagrass Meadows. After excluding green turtles for three months, we found that grazing only impacted Seagrasses at one site, where green turtles created a grazing plot by actively feeding on both above and below ground Seagrass structures, a rare observation for the species. Within this grazing plot at the end of the experiment, the un-caged control treatments open to grazing had a 60% reduction in both above and below ground biomass, and shoot height was reduced by 75%, but there was no impact of grazing on the Seagrass species mix. Our study shows that grazing plot formation by green turtles occurs in GBR fast growing Seagrass communities and reduces both above and below ground Seagrass biomass, this behaviour may be targeting elevated leaf nutrients, or nutritional content of rhizomes. This study is the first documented case of grazing plot formation by green turtles in the GBR and suggests that grazing pressure has a major influence on Seagrass Meadow structure.
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Herbivory Has a Major Influence on Structure and Condition of a Great Barrier Reef Subtropical Seagrass Meadow
Estuaries and Coasts, 2020Co-Authors: Abigail L. Scott, Paul H. York, Michael A. RasheedAbstract:Grazing by all members of an herbivore community can act to structure the ecosystems they feed on. The outcome of this grazing pressure on the plant community also depends on the interaction between different herbivore groups that are present. We carried out a three-month multi-level field exclusion experiment to understand how different groups of herbivores act both individually and interactively to structure a subtropical Seagrass Meadow in the Great Barrier Reef. Megaherbivore grazing had the largest impact on this Seagrass Meadow, significantly reducing aboveground biomass and shoot height, whereas there was no measurable impact of meso- or macroherbivores on Seagrass metrics or epiphyte biomass. Megaherbivores here grazed broadly across the Meadow instead of targeting grazing in one area. The principal Seagrass-herbivore dynamic in this Meadow is that megaherbivores are the main group modifying Meadow structure, and other grazer groups that are present in lower numbers do not individually or interactively structure the Meadow. We demonstrate that herbivory by large grazers can significantly modify Seagrass Meadow characteristics. This has important implications when designing and interpreting the results of monitoring programs that seek to conserve Seagrass Meadows, the ecosystem services that they provide and the herbivores that rely on them. Collectively, our results and those of similar previous studies emphasize there is unlikely to be one Seagrass and herbivory paradigm. Instead, for individual Meadows, their unique species interactions and differences in biotic and abiotic drivers of Seagrass change are likely to have a strong influence on the dominant Seagrass-herbivore dynamic.
David A Koweek - One of the best experts on this subject based on the ideXlab platform.
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expected limits on the ocean acidification buffering potential of a temperate Seagrass Meadow
Ecological Applications, 2018Co-Authors: David A Koweek, Kathryn Hewett, Brian Gaylord, Sarah N Giddings, Yuichiro Takeshita, Jennifer L Ruesink, Kerry J Nickols, John J Stachowicz, Richard C Zimmerman, Ken CaldeiraAbstract:Author(s): Koweek, David A; Zimmerman, Richard C; Hewett, Kathryn M; Gaylord, Brian; Giddings, Sarah N; Nickols, Kerry J; Ruesink, Jennifer L; Stachowicz, John J; Takeshita, Yuichiro; Caldeira, Ken | Abstract: Ocean acidification threatens many marine organisms, especially marine calcifiers. The only global-scale solution to ocean acidification remains rapid reduction in CO2 emissions. Nevertheless, interest in localized mitigation strategies has grown rapidly because of the recognized threat ocean acidification imposes on natural communities, including ones important to humans. Protection of Seagrass Meadows has been considered as a possible approach for localized mitigation of ocean acidification due to their large standing stocks of organic carbon and high productivity. Yet much work remains to constrain the magnitudes and timescales of potential buffering effects from Seagrasses. We developed a biogeochemical box model to better understand the potential for a temperate Seagrass Meadow to locally mitigate the effects of ocean acidification. Then we parameterized the model using data from Tomales Bay, an inlet on the coast of California, USA which supports a major oyster farming industry. We conducted a series of month-long model simulations to characterize processes that occur during summer and winter. We found that average pH in the Seagrass Meadows was typically within 0.04 units of the pH of the primary source waters into the Meadow, although we did find occasional periods (hours) when Seagrass metabolism may modify the pH by up to ±0.2 units. Tidal phasing relative to the diel cycle modulates localized pH buffering within the Seagrass Meadow such that maximum buffering occurs during periods of the year with midday low tides. Our model results suggest that Seagrass metabolism in Tomales Bay would not provide long-term ocean acidification mitigation. However, we emphasize that our model results may not hold in Meadows where assumptions about depth-averaged net production and seawater residence time within the Seagrass Meadow differ from our model assumptions. Our modeling approach provides a framework that is easily adaptable to other Seagrass Meadows in order to evaluate the extent of their individual buffering capacities. Regardless of their ability to buffer ocean acidification, Seagrass Meadows maintain many critically important ecosystem goods and services that will be increasingly important as humans increasingly affect coastal ecosystems.
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expected limits on the ocean acidification buffering potential of a temperate Seagrass Meadow
Ecological Applications, 2018Co-Authors: David A Koweek, Kathryn Hewett, Brian Gaylord, Sarah N Giddings, Yuichiro Takeshita, Jennifer L Ruesink, Kerry J Nickols, John J Stachowicz, Richard C Zimmerman, Ken CaldeiraAbstract:Ocean acidification threatens many marine organisms, especially marine calcifiers. The only global-scale solution to ocean acidification remains rapid reduction in CO2 emissions. Nevertheless, interest in localized mitigation strategies has grown rapidly because of the recognized threat ocean acidification imposes on natural communities, including ones important to humans. Protection of Seagrass Meadows has been considered as a possible approach for localized mitigation of ocean acidification due to their large standing stocks of organic carbon and high productivity. Yet much work remains to constrain the magnitudes and timescales of potential buffering effects from Seagrasses. We developed a biogeochemical box model to better understand the potential for a temperate Seagrass Meadow to locally mitigate the effects of ocean acidification. Then we parameterized the model using data from Tomales Bay, an inlet on the coast of California, USA which supports a major oyster farming industry. We conducted a series of month-long model simulations to characterize processes that occur during summer and winter. We found that average pH in the Seagrass Meadows was typically within 0.04 units of the pH of the primary source waters into the Meadow, although we did find occasional periods (hours) when Seagrass metabolism may modify the pH by up to ±0.2 units. Tidal phasing relative to the diel cycle modulates localized pH buffering within the Seagrass Meadow such that maximum buffering occurs during periods of the year with midday low tides. Our model results suggest that Seagrass metabolism in Tomales Bay would not provide long-term ocean acidification mitigation. However, we emphasize that our model results may not hold in Meadows where assumptions about depth-averaged net production and seawater residence time within the Seagrass Meadow differ from our model assumptions. Our modeling approach provides a framework that is easily adaptable to other Seagrass Meadows in order to evaluate the extent of their individual buffering capacities. Regardless of their ability to buffer ocean acidification, Seagrass Meadows maintain many critically important ecosystem goods and services that will be increasingly important as humans increasingly affect coastal ecosystems.
Mohammad Rozaimi - One of the best experts on this subject based on the ideXlab platform.
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coralline macroalgae contribution to ecological services of carbon storage in a disturbed Seagrass Meadow
Marine Environmental Research, 2020Co-Authors: Natasha Arina, Nur Hidayah, Chandran Raynusha, Nur Farah Ain Zainee, Anchana Prathep, Mohammad RozaimiAbstract:Abstract Coralline macroalgae are globally distributed rhodopyhtes that remove carbon from their immediate environment and transform it into carbonate sediments through the senescence of their calcified tissues. In this study, the calcium carbonate (CaCO3) stocks in the tissue of Jania adhaerens and sediments in Tanjung Adang Shoal, Johor were quantified for a 13-month study period. The detailed maps of the geographical distribution based on the spatial and temporal variations of biomass and CaCO3 were also assessed. The highest amount of biomass, CaCO3 and organic carbon (OC) stocks in the tissues showed the highest in May 2018 and May 2019. The biomass values ranged from 65 to 143 g DW m−2, which contained 53–147 g CaCO3 m−2 and 3–11 g OC m−2. These findings provided insights into the biogeochemical cycling of these inputs, which can be used to estimate the overall carbon budget of the macrophyte Meadow.
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nitrogen dynamics within an estuarine Seagrass Meadow under heavy anthropogenic influence
Marine Pollution Bulletin, 2020Co-Authors: Che Nurul Ashikin, Mohammad Rozaimi, Natasha Arina, Mohammad Fairoz, Nur HidayahAbstract:Abstract Nitrogen is essential for Seagrass productivity but excesses in nitrogen exposure contribute to declines in Meadow health. This study reports baseline data of bulk nitrogen loadings and contents in surficial sediments and Seagrass tissues to determine the extent of nitrogen inputs in Meadows of Sungai Pulai estuary (Johor, Malaysia). The sediment contained relatively low nitrogen loadings (mean range of 91–94 g N m−2) with likely origins from land-based sources. At the Meadow-level, Enhalus acoroides, Cymodocea serrulata and Thalassia hemprichii are the most important species as nitrogen sinks. The highest δ15N values of Seagrass tissues were recorded for T. hemprichii (10.7 ± 0.4‰), which indicated an elevated capacity for internal recycling of nitrogen. The data demonstrates the provision of ecosystem services by the Meadows in mitigating excess nitrogen imported into the estuary. Seagrasses health, however, needs to be at optimum levels for the effectiveness of the Meadow as a nutrient sink.
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records of sea star echinodermata asteroidea diversity in a disturbed tropical Seagrass Meadow
Arxius de Miscel·lània Zoològica, 2018Co-Authors: Mohammad Fairoz, Mohammad Rozaimi, W F NastasiaAbstract:espanolEl objetivo de este estudio es registrar la distribucion de estrellas de mar en las praderas marinas del estuario Sungai Pulai (Johor, Malasia), donde estan sometidas a presion ambiental debido a la modificacion de las actividades en la costa. Los puntos de muestreo fueron Merambong Shoal, Tanjung Adang Shoal, Tanjung Bin y Sungai Duku. Desde enero de 2016 hasta marzo de 2018 observamos las areas de estudio para realizar un inventario de las especies de estrellas de mar presentes durante la marea baja. Observamos un total de siete especies, siendo Merambong Shoal el area con el mayor numero de especies (siete especies), mientras que Sungai Duku y Tanjung Bin presentaron el numero mas bajo (una especie). Registramos la primera observacion de Astropecten vappa en esta area, que sumada a los hallazgos de estudios anteriores supone un total de ocho especies. Nuestros hallazgos referentes a la comunidad estrellas de mar podrian ser aplicables como valores de referencia para la gestion de las praderas marinas como habitat, asi como para sensibilizar acerca de la diversidad de estrellas de mar en esta area. catalaL’objectiu d’aquest estudi es registrar la distribucio d’estrelles de mar a les praderies marines de l’estuari Sungai Pulai (Johor, Malaisia), on estan sotmeses a pressio ambiental a causa de la modificacio de les activitats a la costa. Els punts de mostreig van ser Merambong Shoal, Tanjung Adang Shoal, Tanjung Bin i Sungai Duku. Des del gener de 2016 fins al marc de 2018 vam observar les arees d’estudi per fer un inventari de les especies d’estrelles de mar presents durant la marea baixa. Hi vam observar un total de set especies. L’area de Merambong Shoal es la que va presentar un nombre mes gran d’especies, set, mentre que Sungai Duku i Tanjung Bin van presentar el nombre mes baix, una cadascun. Vam registrar la primera observacio d’Astropecten vappa en aquesta area, que sumada a les troballes d’estudis anteriors suposa un total de vuit especies. Les nostres troballes referents a la comunitat d’estrelles de mar podrien ser aplicables com a valors de referencia per a la gestio de les praderies marines com a habitat i tambe per sensibilitzar sobre la diversitat d’estrelles de mar en aquesta area. EnglishThis study aims to record the sea star distribution in Seagrass Meadows within Sungai Pulai estuary (Johor, Malaysia) that is under pressure from coastal modification activities. The sampling sites were Merambong Shoal, Tanjung Adang Shoal, Tanjung Bin and Sungai Duku. From January 2016 to March 2018, we surveyed the areas to provide an inventory of sea star species sighted during the lowest tides. A total of seven species were observed, with Merambong Shoal having the highest number of species (seven species) while Sungai Duku and Tanjung Bin had the lowest (one species). We report the first sighting of Astropecten vappa in the area. Combined with past studies, there are now a total of eight sea star species in this area. As baseline records, our findings for the sea star community are applicable to the management of the Seagrass habitat and help to create awareness of sea star diversity in the area.
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carbon stores from a tropical Seagrass Meadow in the midst of anthropogenic disturbance
Marine Pollution Bulletin, 2017Co-Authors: Mohammad Rozaimi, Mohammad Fairoz, Tuan Mohamad Hakimi, Nur Hidayah Hamdan, Ramlan Omar, Masni Mohd Ali, Siti Aishah TahirinAbstract:Abstract Seagrass Meadows provide important carbon sequestration services but anthropogenic activities modify the natural ecosystem and inevitably lower carbon storage capacity. The tropical mixed-species Meadows in the Sungai Pulai Estuary (Johor, Malaysia) are impacted by such activities. In this study, we provide baseline estimates for carbon stores analysed from sediment cores. In sediment depths up to 100 cm, organic (OC) and inorganic carbon (IC) stores were 43–101 Mg C ha − 1 and 46–83 Mg C ha − 1 , respectively, and are in the lower end of global average values. The bulk of OC (53–98%) originated from seston suggesting that the Meadows had low capacity to retain Seagrass-derived organic matter. The species factor resulted in some variability in OC stores but did not appear to influence IC values. The low carbon stores in the Meadow may be a direct result of sediment disturbances but natural biogeochemical processes are not discounted as possible causal factors.