Thongchai Thailand

TBGY Does Blue Carbon

Posted on: February 13, 2020








  1. We know that our PLANET is not just made up of land and air. More than 70% of it is covered by the water in our oceans; and those oceans are the biggest carbon sink that we’ve got. Satellites are helping our scientists to get a clearer picture of how our oceans are absorbing a very significant proportion of the extra carbon dioxide we humans are emitting into the atmosphere. And we are also just beginning to understand some of the more disastrous consequences of that extra CO2 absorption. Consequences like OCEAN ACIDIFICATION [RELATED POST] which among other things is affecting the long term viability of shell fish and coral reefs. But human activity and climate change are not just altering the composition and temperature of our open oceans. They are also beginning to threaten ecosystems along our coastlines. And that could have the consequence of releasing huge quantities of CO2 from what our scientists refer to as BLUE CARBON. bandicam 2020-02-04 11-05-42-710
  2. The scale of our seas and oceans is mind boggling. As well as covering three quarters of the planet, they produce 50% of the world’s oxygen and absorb 90% of the excess heat accumulated in our PLANET’s climate system. According to the “IPCC Special Report on the “Ocean and Cryosphere in a Changing Climate“, the oceans also take up 1/3 of all the carbon emitted as a direct result of human activity. And all that carbon uptake is slowing the rate of increase in the warming of our atmosphere but it’s also causing all this scientific anxiety on the negative side effects like ocean acidification. bandicam 2020-02-02 18-54-30-240
  3. What about this blue carbon, then? The IPCC report tells us that blue carbon is carbon stored in coastal wetlands such as salt marshes, mangrove forests, and sub-tidal seagrass meadows. According to an action program called “Mitigating Climate Change Through Coastal Ecosystem Management Blue Carbon Initiative” [LINK] , these coastal ecosystems capture more carbon per unit area than the forests on land. Their website offers a few more statistics. It says that 83% of the global carbon cycle is circulated through the ocean. Although coastal habitats cover less than 2% of the total ocean area, they account for about half of the carbon sequestered in ocean sediments. Which is quite significant!  bandicam 2020-01-15 16-14-44-019
  4. These coastal ecosystems are also some of the most productive on earth giving us humans crucial coastal protection from storms and providing a critical habitat for marine species that make that make up a major part of people’s food security and income. They also improve and maintain water quality along coastlines for coastal countries worldwide. And they are one of the planet’s most prolific nurturing grounds for fish. The IPCC Special Report on the Oceans and Cryosphere says “Although they occupy a small part of the global ocean (7.6%), coastal seas provide up to 30% of global marine primary production and about 50% of the organic carbon supplied to the deep ocean. bandicam 2020-02-03 18-19-37-543
  5. In our ignorance, we humans sadly, have already done great damage to these vital resources. According to the Blue Carbon Initiative, lots of mangrove habitats are causing carbon emissions that account for 10% of all deforestation globally, even though they cover only 0.7% of the area. Tidal marshes are being lost at a rate of 1% to 3% per year. They currently cover about 140 million hectares (0.4% of the ocean) of the surface of the earth, an area almost the size of Alaska. They have lost more than 50% of their historical global coverage. Seagrass meadows cover less than 0.3% of the ocean floor but still store about 10% of the carbon buried in the ocean each year. A Guardian article points out that unlike forests that store carbon for about 60 years before releasing much of it, seagrass meadows often store the carbon for thousands of years until they are disturbed. That process is thought to offset up to 2% of humanity’s greenhouse gas emissions [LINK] . The Guardian article goes on to say that since the start of the 20th century, seagrass meadows worldwide have declined at an average rate of 0.9% per year, mostly due to direct human impacts such as coastal development and water quality degradation. Over the last century about 29% of global seagrass has been destroyed and it is releasing carbon at a rate similar to the rate of Australia and the UK combined. bandicam 2020-02-02 17-44-30-599
  6. So as well as being battered by physical human intervention, all of these precious habitats, are really beginning to suffer as our ocean waters warm. The IPCC tells us that seagrass meadows in particular are highly sensitive to temperature change in the ocean. Back in the Australian summer of 2010-2011, a phenomenon known as marine heat wave hit one of the largest seagrass meadows on earth in an area called Shark Bay [LINK] in Western Australia. About 1.3% of all the CO2 stored by seagrass across the entire world is stored there. The underwater heat wave caused the water to warm locally by up to 4C resulting in a loss of about 36% of the area these flowering {reenpunts???}. Events like this pose a high penalty on our environment as described in a 2018 article by David Nield [LINK] . He says “Losing seagrass is a double whammy for our environment’s health. Not only do we lose the plant’s ability to capture and store CO2, but all the CO2 that’s already being stored gets released back out into the ecosystem“. dugong
  7. The IPCC tell us that as human CO2 emissions have warmed out atmosphere, and out oceans have been absorbing 90% of the heat that this emissions have been producing, so the occurrence of marine heat waves has doubled since the 1980s. Research by conservation international also suggests that the global average number of marine heat wave days has increased by about 50%. This means that an ocean area that might have experienced 30 days of ocean heat wave temperatures will not be enjoying more like 45 days of ocean heat wave temperatures. And that extreme exposure to extreme heat is putting unsustainable and in many cases un-survive-able stresses onto those delicate ecosystems. The IPCC report also points to other climate related factors now threatening coastal wetlands. They state with high confidence that wetland salinization is occurring on a large geographical scale. They also point out that sea level rise combined with more extreme storms are causing wetland erosion and habitat loss. bandicam 2020-02-13 15-09-18-689
  8. So the obvious question is what’s being done to slow or reverse the decline of these absolutely vital blue carbon stores. According to the Blue Carbon Initiative website [LINK]is working on conservation science, policy, and management of blue carbon ecosystems globally. Their major objectives are national level accounting of carbon stocks and emissions from blue carbon ecosystems, increased management effectiveness of blue carbon ecosystems in protected areas, and the development of blue carbon offsets for tourism activities. WE ARE NOW FULLY IN THE COUNTDOWN TO THE COP 26 CLIMATE CONFERENCE which takes place in Glasgow in November. Another globally important pivotal event is also taking place this November (a reference to Trump) but I will leave that one for others bandicam 2020-02-13 15-36-50-863





  1. Reference: Paragraph#2 – The scale of our seas and oceans is mind boggling. As well as covering three quarters of the planet, they produce 50% of the world’s oxygen and absorb 90% of the excess heat accumulated in our PLANET’s climate system. 
  2. Response: With regard to the invocation of the planet in the discussion of AGW climate change, kindly note that this invocation is part of the desperate aspiration of climate science to describe AGW climate change on a planetary scale such that the fate of the planet is now in our hands and that we can save the planet from its destruction by climate change if we take climate action. This lofty and ambitious posture is inconsistent with what we know about our planet. The crust of the planet consisting of the oceans and land where we live and where we have things like climate and ecosystems and polar bears is only 0.3% of the planet. The other 99.7% of the planet is the  the mantle and the core located underneath the lithosphere where there is no life, no ecosystem, and no climate. AGW climate change cannot be presented as a planetary phenomenon. It is a surface phenomenon that relates only to the crust and its atmosphere that together form 0.3% of the planet.
  3. Reference: Paragraph#3: – Blue Carbon Sequestration in Coastal EcosystemsBlue carbon is carbon stored in coastal wetlands such as salt marshes, mangrove forests, and sub-tidal seagrass meadows. These coastal ecosystems capture more carbon per unit area than the forests on land. Although coastal habitats cover less than 2% of the total ocean area, they account for about half of the carbon sequestered in ocean sediments.
  4. Response: AGW climate change is a theory that the combustion of fossil fuels by the Industrial Economy has introduced external carbon dug up from under the ground into the carbon cycle. It is argued that this carbon does not belong in the current account of the carbon cycle and that therefore its introduction into the delicately balanced carbon cycle and climate system will act as a perturbation to the climate system and cause unnatural human caused warming by way of the greenhouse effect of carbon dioxide. AGW is therefore a theory of the impact of external non-carbon-cycle CO2 flows that increase atmospheric CO2 concentration. This is why carbon cycle flows are not counted as climate forcings. As for example, human respiration contains CO2 but that is part of the carbon cycle and therefore not part of the Industrial Economy external carbon that has upset the climate system. The presentation above does not make this distinction and assigns climate forcing functions to carbon cycle flows such as photosynthesis carbon that is returned to the atmosphere. This illogic also implies that human respiration is a climate forcing although in climate science it is part of the carbon cycle and not a perturbation of the carbon cycle.
  5. Reference: Paragraph#4 – organic carbon in the the deep ocean: Although they occupy a small part of the ocean, coastal seas provide 30% of global marine primary production and 50% of the organic carbon supplied to the deep ocean.
  6. Response:  The key word here is “organic” because geological sources of carbon from plate tectonics, submarine volcanism and hydrothermal vents are orders of magnitude larger and they are the original source of carbon from which all carbon life forms including coastal ecosystems and humans are derived. In terms of both climate science and biology the carbon from these two different sources are indistinguishable.
  7. Reference: Paragraph#5 – declining carbon sequestration by seagrass:  Carbon sequestration by seagrass offsets up to 2% of humanity’s greenhouse gas emissions [LINK] . Since the start of the 20th century, seagrass meadows worldwide have declined at an average rate of 0.9% per year, due to direct human impacts such as coastal development and water quality degradation. Over the last century about 29% of global seagrass has been destroyed and it is releasing carbon at a rate similar to the rate of Australia and the UK combined.
  8. Response:  If seagrass offsets 2% of humanity’s carbon emissions, and if human activity is causing seagrass to decline at 0.9% per year, the net effect on emissions net of seagrass sequestration is an increase of emissions at a rate of 0.018% per year. This rate of increase is well within the uncertainty rate in terms of our ability to measure or estimate human emissions. This means that the impact of coastal ecosystem degradation on AGW climate change is not measurable. The implication for blue carbon activism is two fold. Firstly, the impact of reduction in the ability of coastal ecosystems to sequester carbon on AGW climate change is negligible because it is too small to measure. And secondly, the emphasis on carbon cycle dynamics as the driver of climate change warming is inconsistent with AGW climate change theory which points to the impact of external carbon in fossil fuel emissions on the carbon cycle – and not the carbon cycle itiself – as the driver of global warming.
  9. Reference: Paragraph#6 – the David Nield Article:  The David Nield article [LINK], says that more than a third of the world’s seagrass was affected and that about a third of the seagrass meadows were wiped out by the intense climate change warming in 2014 and that as a result 9 million tonnes of carbon dioxide was released from these coastal ecosystems into the atmosphere. This event is described as “The Ocean Has Released an Insane Amount of CO2 into the atmosphere” and it serves as the dangerous climate change feedback described in the TBGY lecture where climate change warming causes a release of coastal ecosystem carbon which in turn increases the rate of warming.
  10. Response: With regard to the above figures, note that in 2014, global carbon dioxide emissions from fossil fuels for the year added up to about 33 gigatonnes (GT) of carbon dioxide equivalent to 33,000 million tonnes. The 9 million tonnes added by the destruction of coastal ecosystems is approximately 0.027% of fossil fuel emissions in 2014 that is well within the error margin of the fossil fuel emissions estimate. If, instead of only a third, all of the world’s seagrass meadows had had undergone this insane carbon release, the total amount of CO2 released may have been in the order of 3×9 or 27 million tonnes or about 0.08% of fossil fuel emissions – also well within the uncertainty rate of the fossil fuel emissions estimate. These figures do not indicate that carbon release from coastal ecosystems is the kind of AGW climate change catastrophe described in the lecture.
  11. Reference: Paragraph#6 – Marine Heat Waves: Back in the Australian summer of 2010-2011, a phenomenon known as marine heat wave hit one of the largest seagrass meadows on earth in an area called Shark Bay [LINK] in Western Australia. About 1.3% of all the CO2 stored by seagrass across the entire world is stored there. The underwater heat wave caused the water to warm locally by up to 4C resulting in a loss of about 36% of the seagrass.
  12. Response: Marine heat waves are described in some detail in a related post [LINK] Marine heat waves are not really heat waves but a temporary SST (sea surface temperature) anomaly that last more than 5 days. They tend to be found repeatedly in the same geographical location that are usually shallow and close to land. The term “heat wave” is a misnomer although marine heat waves do harm the ecosystems in the shallow sea close to land where they form. Such locations of course conform to those of coastal ecosystems and therefore these ecosystems are likely to be exposed to marine heat waves. However, marine heat waves can’t be described as “underwater heat waves” nor are they a heat wave in the way we understand them in terms of our experience in atmospheric heat waves. Underwater heat events do occur in the deep ocean but these are geological phenomena that transfer heat from the mantle to the ocean. The terms “Marine Heat wave” and “Blue Carbon” are highly charged phrases that belie their more mundane references.
  13. CONCLUSION: We conclude from the data and analysis presented above that the blue carbon issue does not have implications for AGW climate change because the issue in AGW is not carbon cycle flows but the perturbation of the current account of the carbon cycle by external carbon (external to the current account of the carbon cycle) dug up from under the ground where it had been sequestered from the carbon cycle for millions of years. In addition we find that the claimed contribution of blue carbon to AGW forcing as a result of coastal ecosystem degradation is negligible and well within the uncertainty band of the estimates of carbon flows from fossil fuel emissions. 






  1. Dennison, William C. “Effects of light on seagrass photosynthesis, growth and depth distribution.” Aquatic Botany 27.1 (1987): 15-26. The relationships between light regime, photosynthesis, growth and depth distribution of a temperate seagrass, Zostera marina L. (eelgrass), were investigated in a subtidal eelgrass meadow near Woods Hole, MA. The seasonal light patterns in which the quantum irradiance exceeded the light compensation point (Hcomp) and light saturation point (Hsat) for eelgrass photosynthesis were determined. Along with photosynthesis and respiration rates, these patterns were used to predict carbon balances monthly throughout the year. Gross photosynthesis peaked in late-summer, but net photosynthesis peaked in spring (May), due to high respiration rates at summer temperatures. Predictions of net photosynthesis correlated with in situ growth rates at the study site and with reports from other locations. The maximum depth limit for eelgrass was related to the depth distribution of Hcomp, and a minimum annual average Hcomp (12.3 h) for survival was determined. Maximum depth limits for eelgrass were predicted for various light extinction coefficients and a relationship between Secchi disc depth and the maximum depth limit for survival was established. The Secchi disc depth averaged over the year approximates the light compensation depth for eelgrass. This relationship may be applicable to other sites and other seagrass species.
  2. Borowitzka, MAß, and R. C. Lethbridge. “Seagrass epiphytes.” Elsevier Science Pub., 1989. 458-499. Epiphytes are those organisms which grow upon plants. In aquatic environments macrophytes are usually rapidly colonized by microorganisms such as bacteria and micro-algae, and later by larger algae and invertebrates unless the macrophytes have chemical or physical mechanisms for excluding these organisms. Much of the literature on seagrass epiphytes is concerned with taxonomy (e.g. Humm, 1964; Marsh, 1973; May et al., 1978; Harlin, 1980; Pansini and Pronzato, 1985), and shows that seagrasses are colonized by a diverse range of algae and sessile invertebrates such as hydroids, bryozoans and sponges. In this paper we shall not provide further lists of epiphytic organisms, but rather will consider the distribution of the epiphytic organisms on individual seagrasses, between different seagrass species, and at different localities. We shall also discuss the mechanisms of colonization and recruitment, and the role of these epiphytic organisms in the ecology of seagrass communities.
  3. Duarte, Carlos M. “Seagrass nutrient content.” Marine ecology progress series. Oldendorf 6.2 (1990): 201-207. aBSTRACT: Data on nutrient contents of 27 seagrass species at 30 locations were compiled from the literature. Mean (f SE) concentrations of carbon, nitrogen and phosphorus in seagrass leaves were 33.6 20.31, 1.92 f 0.05, and 0.23 2 0.011 % dry wt, respectively. The median C:N:P ratio was 474 :24: 1, which represents a C:P ratio more than 4 times, and a N:P ratio more than 1.5 times that of oceanic seston. These ratios are, however, less than those previously reported for marine macrophytes (550 : 30 : 1) by Atkinson & Smith (1984). Nitrogen and phosphorus variability within species was large, but carbon contents exhibited little variability. Accordingly, carbon:nutrient (N and P) ratios were inversely related to changes in nutrient content, and the rate of change in C:N and C:P ratios with increasing nitrogen or phosphorus content in plant tissues should shift from high to small as nutrient supply meets the plant’s demands. The median nitrogen and phosphorus contents reported here (1.8 % N and 0.20 % P as % DW) correctly discriminated between seagrass stands that did or did not respond to nutrient enrichment, thus offering a useful reference for comparisons of seagrass nutrient contents.
  4. Duarte, Carlos M. “Seagrass depth limits.” Aquatic botany 40.4 (1991): 363-377.  Examination of the depth limit of seagrass communities distributed worldwide showed that sea-grasses may extend from mean sea level down to a depth of 90 m, and that differences in seagrass depth limit (Zc) are largely attributable to differences in light attenuation underwater (K). This relationship is best described by the equation log Zc(m) = 0.26 − 1.07logK (m−)that holds for a large number of marine angiosperm species, although differences in seagrass growth strategy and architecture also appear to contribute to explain differences in their depth limits. The equation relating seagrass depth limit and light attenuation coefficient is qualitatively similar to previous equations developed for freshwater angiosperms, but predicts that seagrasses will colonize greater depths than freshwater angiosperms in clear (transparency greater than 10 m) waters. Further, the reduction in seagrass biomass from the depth of maximum biomass towards the depth limit is also closely related to the light attenuation coefficient. The finding that seagrasses can extend to depths receiving, on average, about 11% of the irradiance at the surface, together with the use of the equation described, may prove useful in the identification of seagrass meadows that have not reached their potential extension.
  5. Michener, William K., et al. “Climate change, hurricanes and tropical storms, and rising sea level in coastal wetlands.” Ecological Applications 7.3 (1997): 770-801.  Global climate change is expected to affect temperature and precipitation patterns, oceanic and atmospheric circulation, rate of rising sea level, and the frequency, intensity, timing, and distribution of hurricanes and tropical storms. The magnitude of these projected physical changes and their subsequent impacts on coastal wetlands will vary regionally. Coastal wetlands in the southeastern United States have naturally evolved under a regime of rising sea level and specific patterns of hurricane frequency, intensity, and timing. A review of known ecological effects of tropical storms and hurricanes indicates that storm timing, frequency, and intensity can alter coastal wetland hydrology, geomorphology, biotic structure, energetics, and nutrient cycling. Research conducted to examine the impacts of Hurricane Hugo on colonial waterbirds highlights the importance of long‐term studies for identifying complex interactions that may otherwise be dismissed as stochastic processes. Rising sea level and even modest changes in the frequency, intensity, timing, and distribution of tropical storms and hurricanes are expected to have substantial impacts on coastal wetland patterns and processes. Persistence of coastal wetlands will be determined by the interactions of climate and anthropogenic effects, especially how humans respond to rising sea level and how further human encroachment on coastal wetlands affects resource exploitation, pollution, and water use. Long‐term changes in the frequency, intensity, timing, and distribution of hurricanes and tropical storms will likely affect biotic functions (e.g., community structure, natural selection, extinction rates, and biodiversity) as well as underlying processes such as nutrient cycling and primary and secondary productivity.Reliable predictions of global‐change impacts on coastal wetlands will require better understanding of the linkages among terrestrial, aquatic, wetland, atmospheric, oceanic, and human components. Developing this comprehensive understanding of the ecological ramifications of global change will necessitate close coordination among scientists from multiple disciplines and a balanced mixture of appropriate scientific approaches. For example, insights may be gained through the careful design and implementation of broad‐scale comparative studies that incorporate salient patterns and processes, including treatment of anthropogenic influences. Well‐designed, broad‐scale comparative studies could serve as the scientific framework for developing relevant and focused long‐term ecological research, monitoring programs, experiments, and modeling studies. Two conceptual models of broad‐scale comparative research for assessing ecological responses to climate change are presented: utilizing space‐for‐time substitution coupled with long‐term studies to assess impacts of rising sea level and disturbance on coastal wetlands, and utilizing the moisture‐continuum model for assessing the effects of global change and associated shifts in moisture regimes on wetland ecosystems. Increased understanding of climate change will require concerted scientific efforts aimed at facilitating interdisciplinary research, enhancing data and information management, and developing new funding strategies.
  6. Duarte, Carlos M., and Carina L. Chiscano. “Seagrass biomass and production: a reassessment.” Aquatic botany 65.1-4 (1999): 159-174.  The biomass and production of seagrass populations were reassessed based on the compilation of a large data set comprising estimates for 30 species, derived from the literature. The mean (± SE) above- and below-ground biomass in the data set were very similar, 223.9 ± 17.5 and 237.4 ± 28 g DW m−2, respectively, indicating a general tendency for a balanced distribution of biomass between leaves and rhizomes + roots (mean ratio (± SE) = 1.11 ± 0.08). The biomass development and the ratio of above- to below-ground biomass varied significantly with latitude and was species-specific, with a significant tendency for large-sized seagrass species to develop high below-ground biomass. Maximum daily seagrass production differed significantly among species, but averaged 3.84 ± 0.34 and 1.21 ± 0.27 g DW m−2 per day for above- and below-ground organs respectively, with an average ratio of above- to below-ground production of 16.4 ± 8.5. The biomass turnover rates averaged 2.6 ± 0.3 and 0.77 ± 0.12% per day for the above– and below-ground material respectively, and tended to be faster for temperate species. The average annual seagrass production found here, 1012 g DW m−2 per year, exceeds previous estimates by 25%, because the average excedent carbon produced by seagrasses must be revised upwards to represent 15% of the total surplus carbon fixed in the global ocean.
  7. Waycott, Michelle. “Genetic factors in the conservation of seagrasses.” Pacific Conservation Biology 5.4 (1999): 269-276.  Increasingly our awareness of seagrass conservation issues requires an understanding of population dynamics and knowledge of the ability of different species to recover from disturbance. Seagrass populations may recover vegetatively or through the establishment of sexually derived seedlings. Some understanding of the processes of population formation and maintenance can be obtained through population genetic surveys. With the advent of molecular genetic markers even genetically depauperate populations can be studied. Patterns of genetic variation can vary over the range of seagrass populations and with the type of marker used. A case study is presented which demonstrates the importance of surveying a significant range of species to better understand the patterns of genetic diversity present. Seagrass phylogeny needs to be improved before reliable taxonomic interpretations can be made in many seagrass groups. Uncommon or rare seagrass species require special attention to ascertain their evolutionary origins and the nature of their extant distributions. Studies of genetic factors may enhance our understanding of how seagrass populations survive over both short and long time scales and can provide considerable insight to the seagrass conservation strategist.
  8. Duarte, Carlos M. “The future of seagrass meadows.” Environmental conservation 29.2 (2002): 192-206 Seagrasses cover about 0.1–0.2% of the global ocean, and develop highly productive ecosystems which fulfil a key role in the coastal ecosystem. Widespread seagrass loss results from direct human impacts, including mechanical damage (by dredging, fishing, and anchoring), eutrophication, aquaculture, siltation, effects of coastal constructions, and food web alterations; and indirect human impacts, including negative effects of climate change (erosion by rising sea level, increased storms, increased ultraviolet irradiance), as well as from natural causes, such as cyclones and floods. The present review summarizes such threats and trends and considers likely changes to the 2025 time horizon. Present losses are expected to accelerate, particularly in South-east Asia and the Caribbean, as human pressure on the coastal zone grows. Positive human effects include increased legislation to protect seagrass, increased protection of coastal ecosystems, and enhanced efforts to monitor and restore the marine ecosystem. However, these positive effects are unlikely to balance the negative impacts, which are expected to be particularly prominent in developing tropical regions, where the capacity to implement conservation policies is limited. Uncertainties as to the present loss rate, derived from the paucity of coherent monitoring programmes, and the present inability to formulate reliable predictions as to the future rate of loss, represent a major barrier to the formulation of global conservation policies. Three key actions are needed to ensure the effective conservation of seagrass ecosystems: (1) the development of a coherent worldwide monitoring network, (2) the development of quantitative models predicting the responses of seagrasses to disturbance, and (3) the education of the public on the functions of seagrass meadows and the impacts of human activity.
  9. Orth, Robert J., et al. “A global crisis for seagrass ecosystems.” Bioscience 56.12 (2006): 987-996. Seagrasses, marine flowering plants, have a long evolutionary history but are now challenged with rapid environmental changes as a result of coastal human population pressures. Seagrasses provide key ecological services, including organic carbon production and export, nutrient cycling, sediment stabilization, enhanced biodiversity, and trophic transfers to adjacent habitats in tropical and temperate regions. They also serve as “coastal canaries,” global biological sentinels of increasing anthropogenic influences in coastal ecosystems, with large-scale losses reported worldwide. Multiple stressors, including sediment and nutrient runoff, physical disturbance, invasive species, disease, commercial fishing practices, aquaculture, overgrazing, algal blooms, and global warming, cause seagrass declines at scales of square meters to hundreds of square kilometers. Reported seagrass losses have led to increased awareness of the need for seagrass protection, monitoring, management, and restoration. However, seagrass science, which has rapidly grown, is disconnected from public awareness of seagrasses, which has lagged behind awareness of other coastal ecosystems. There is a critical need for a targeted global conservation effort that includes a reduction of watershed nutrient and sediment inputs to seagrass habitats and a targeted educational program informing regulators and the public of the value of seagrass meadows. Seagrasses—a unique group of flowering plants that have adapted to exist fully submersed in the sea—profoundly influence the physical, chemical, and biological environments in coastal waters, acting as ecological engineers (sensuWright and Jones 2006) and providing numerous important ecological services to the marine environment (Costanza et al. 1997). Seagrasses alter water flow, nutrient cycling, and food web structure (Hemminga and Duarte 2000). They are an important food source for megaherbivores such as green sea turtles, dugongs, and manatees, and provide critical habitat for many animals, including commercially and recreationally important fishery species (figure 1Beck et al. 2001). They also stabilize sediments and produce large quantities of organic carbon. However, seagrasses and these associated ecosystem services are under direct threat from a host of anthropogenic influences.
  10. Bayliss, Peter, et al. “Modelling the spatial relationship between dugong (Dugong dugon) and their seagrass habitat in Shark Bay Marine Park before and after the marine heatwave of 2010/11.”  [FULL TEXT PDF]   Shark Bay is a global strong-hold for dugongs because of its extensive stands of seagrass. In the late summer of 2010/11 a marine heatwave occurred in WA coastal waters that had a significant impact on key marine habitats, including the large- cale loss of seagrass in Shark Bay Marine Park that has shown limited signs of recovery. An aerial survey of dugong populations in the Shark Bay-Ningaloo- xmouth Gulf region was therefore undertaken in June 2018 to assess how dugong populations may have responded to the extensive loss of seagrass in 2011. The specific objectives, methodology, population-level analyses and results of that survey are documented in the first report of this project (Appendix 1; Bayliss et al. 2018). 2. The key results from the first report are: the number of dugongs in Shark Bay in 2018 was estimated at 18,555 + 3,396 (SE 18.3%) using the most updated visibility bias correction factors developed by Hagihara et al. (2014, 2018). The estimate for the Exmouth Gulf-Ningaloo region was 4,831 + 1,965 (SE 40.7%), producing a total of 23,386 + 3,124 (SE 16.8%) for both regions combined; preliminary analysis of population trends suggested that no major decline in either region before or after the seagrass dieback event could be detected, however a more comprehensive change analysis complimented with fine-scale spatial modelling of the relationship between dugongs and their seagrass habitat were recommended. Both recommendations comprise major objectives of the following report.
  11. Smale, Dan A., et al. “From fronds to fish: the use of indicators for ecological monitoring in marine benthic ecosystems, with case studies from temperate Western Australia.” Reviews in fish biology and fisheries 21.3 (2011): 311-337.  Ecological indicators are used for monitoring in marine habitats the world over. With the advent of Ecosystem Based Fisheries Management (EBFM), the need for cost effective indicators of environmental impacts and ecosystem condition has intensified. Here, we review the development, utilisation and analysis of indicators for monitoring in marine benthic habitats, (bottom dwellers) and outline important advances made in recent years. We use the unique, speciose benthic system of Western Australia (WA) as a detailed case study, as the development of indicators for EBFM in this region is presently ongoing, and major environmental drivers (e.g. climate change) and fishing practices are currently influencing WA marine systems. As such, the work is biased towards, but not restricted to, indicators that may be important tools for EBFM, such as biodiversity surrogates and indicators of fishing pressure. The review aimed to: (1) provide a concise, up-to-date account of the use of ecological indicators in marine systems; (2) discuss the current, and potential, applications of indicators for ecological monitoring in WA; and (3) highlight priority areas for research and pressing knowledge gaps. We examined indicators derived from benthic primary producers, benthic invertebrates and fish to achieve these goals.
  12. Mcleod, Elizabeth, et al. “A blueprint for blue carbon: toward an improved understanding of the role of vegetated coastal habitats in sequestering CO2.” Frontiers in Ecology and the Environment 9.10 (2011): 552-560.  Recent research has highlighted the valuable role that coastal and marine ecosystems play in sequestering carbon dioxide (CO2). The carbon (C) sequestered in vegetated coastal ecosystems, specifically mangrove forests, seagrass beds, and salt marshes, has been termed “blue carbon”. Although their global area is one to two orders of magnitude smaller than that of terrestrial forests, the contribution of vegetated coastal habitats per unit area to long‐term C sequestration is much greater, in part because of their efficiency in trapping suspended matter and associated organic C during tidal inundation. Despite the value of mangrove forests, seagrass beds, and salt marshes in sequestering C, and the other goods and services they provide, these systems are being lost at critical rates and action is urgently needed to prevent further degradation and loss. Recognition of the C sequestration value of vegetated coastal ecosystems provides a strong argument for their protection and restoration; however, it is necessary to improve scientific understanding of the underlying mechanisms that control C sequestration in these ecosystems. Here, we identify key areas of uncertainty and specific actions needed to address them. [FULL TEXT]
  13. Fourqurean, James W., et al. “Seagrass ecosystems as a globally significant carbon stock.” Nature geoscience 5.7 (2012): 505-509The protection of organic carbon stored in forests is considered as an important method for mitigating climate change. Like terrestrial ecosystems, coastal ecosystems store large amounts of carbon, and there are initiatives to protect these ‘blue carbon’ stores. Organic carbon stocks in tidal salt marshes and mangroves have been estimated, but uncertainties in the stores of seagrass meadows—some of the most productive ecosystems on Earth—hinder the application of marine carbon conservation schemes. Here, we compile published and unpublished measurements of the organic carbon content of living seagrass biomass and underlying soils in 946 distinct seagrass meadows across the globe. Using only data from sites for which full inventories exist, we estimate that, globally, seagrass ecosystems could store as much as 19.9 Pg organic carbon; according to a more conservative approach, in which we incorporate more data from surface soils and depth-dependent declines in soil carbon stocks, we estimate that the seagrass carbon pool lies between 4.2 and 8.4 Pg carbon. We estimate that present rates of seagrass loss could result in the release of up to 299 Tg carbon per year, assuming that all of the organic carbon in seagrass biomass and the top metre of soils is remineralized.
  14. Pendleton, Linwood, et al. “Estimating global “blue carbon” emissions from conversion and degradation of vegetated coastal ecosystems.” PloS one 7.9 (2012). Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems—marshes, mangroves, and seagrasses that may be lost with habitat destruction (‘conversion’). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this ‘blue carbon can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15–1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3–19% of those from deforestation globally, and result in economic damages of $US 6–42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of landuse conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the wellrecognized ecosystem services of coastal habitats.  [FULL TEXT PDF]
  15. Duarte, Carlos M., et al. “The role of coastal plant communities for climate change mitigation and adaptation.” Nature Climate Change 3.11 (2013): 961-968.  Marine vegetated habitats (seagrasses, salt-marshes, macroalgae and mangroves) occupy 0.2% of the ocean surface, but contribute 50% of carbon burial in marine sediments. Their canopies dissipate wave energy and high burial rates raise the seafloor, buffering the impacts of rising sea level and wave action that are associated with climate change. The loss of a third of the global cover of these ecosystems involves a loss of CO2 sinks and the emission of 1 Pg CO2 annually. The conservation, restoration and use of vegetated coastal habitats in eco-engineering solutions for coastal protection provide a promising strategy, delivering significant capacity for climate change mitigation and adaption.
  16. Ullman, Roger, Vasco Bilbao-Bastida, and Gabriel Grimsditch. “Including blue carbon in climate market mechanisms.” Ocean & Coastal Management 83 (2013): 15-18.  Including Blue Carbon in market-based climate policy mechanisms could result in significant funding for coastal ecosystem protection and restoration. The most promising market mechanisms for Blue Carbon are regulated cap-and-trade schemes, even if some are still in development. The largest is UNFCCC, followed by EU ETS, national schemes and sub-national schemes. Although the voluntary carbon market is a current option, it is much less attractive than regulated markets due to its small size and low prices. For Blue Carbon to be included in major regulated schemes, additional work is needed, including scientific research, policy design, economic analysis and policy advocacy. In particular, three activities should be given priority: reorienting scientific research from the natural sequestration to the emissions that occur upon destruction, estimating global and national aggregate figures for these emissions, and promoting Blue Carbon in key policy fora. It should be recognized that the development of major regulated cap-and-trade schemes with Blue Carbon offsets may take several years. Therefore, in the meantime, efforts should also be made to develop national Blue Carbon policies in the countries with the most relevant habitat.
  17. Murdiyarso, Daniel, et al. “The potential of Indonesian mangrove forests for global climate change mitigation.” Nature Climate Change 5.12 (2015): 1089-1092.  Mangroves provide a wide range of ecosystem services, including nutrient cycling, soil formation, wood production, fish spawning grounds, ecotourism and carbon (C) storage1. High rates of tree and plant growth, coupled with anaerobic, water-logged soils that slow decomposition, result in large long-term C storage. Given their global significance as large sinks of C, preventing mangrove loss would be an effective climate change adaptation and mitigation strategy. It has been reported that C stocks in the Indo-Pacific region contain on average 1,023 MgC ha−1 (ref. 2). Here, we estimate that Indonesian mangrove C stocks are 1,083 ± 378 MgC ha−1. Scaled up to the country-level mangrove extent of 2.9 Mha (ref. 3), Indonesia’s mangroves contained on average 3.14 PgC. In three decades Indonesia has lost 40% of its mangroves4, mainly as a result of aquaculture development5. This has resulted in annual emissions of 0.07–0.21 Pg CO2e. Annual mangrove deforestation in Indonesia is only 6% of its total forest loss6; however, if this were halted, total emissions would be reduced by an amount equal to 10–31% of estimated annual emissions from land-use sectors at present. Conservation of carbon-rich mangroves in the Indonesian archipelago should be a high-priority component of strategies to mitigate climate change.
  18. Atwood, Trisha B., et al. “Predators help protect carbon stocks in blue carbon ecosystems.” Nature Climate Change 5.12 (2015): 1038-1045Predators continue to be harvested unsustainably throughout most of the Earth’s ecosystems. Recent research demonstrates that the functional loss of predators could have far-reaching consequences on carbon cycling and, by implication, our ability to ameliorate climate change impacts. Yet the influence of predators on carbon accumulation and preservation in vegetated coastal habitats (that is, salt marshes, seagrass meadows and mangroves) is poorly understood, despite these being some of the Earth’s most vulnerable and carbon-rich ecosystems. Here we discuss potential pathways by which trophic downgrading affects carbon capture, accumulation and preservation in vegetated coastal habitats. We identify an urgent need for further research on the influence of predators on carbon cycling in vegetated coastal habitats, and ultimately the role that these systems play in climate change mitigation. There is, however, sufficient evidence to suggest that intact predator populations are critical to maintaining or growing reserves of ‘blue carbon‘ (carbon stored in coastal or marine ecosystems), and policy and management need to be improved to reflect these realities.
  19. Kroeger, Kevin D., et al. “Restoring tides to reduce methane emissions in impounded wetlands: A new and potent Blue Carbon climate change intervention.” Scientific reports 7.1 (2017): 1-12Coastal wetlands are sites of rapid carbon (C) sequestration and contain large soil C stocks. Thus, there is increasing interest in those ecosystems as sites for anthropogenic greenhouse gas emission offset projects (“Blue Carbon”), through preservation of existing C stocks or creation of new wetlands to increase future sequestration. Here we show that in the globally-widespread occurrence of diked, impounded, drained and tidally-restricted salt marshes, substantial methane (CH4) and CO2 emission reductions can be achieved through restoration of disconnected saline tidal flows. Modeled climatic forcing indicates that tidal restoration to reduce emissions has a much greater impact per unit area than wetland creation or conservation to enhance sequestration. Given that GHG emissions in tidally-restricted, degraded wetlands are caused by human activity, they are anthropogenic emissions, and reducing them will have an effect on climate that is equivalent to reduced emission of an equal quantity of fossil fuel GHG. Thus, as a landuse-based climate change intervention, reducing CH4 emissions is an entirely distinct concept from biological C sequestration projects to enhance C storage in forest or wetland biomass or soil, and will not suffer from the non-permanence risk that stored C will be returned to the atmosphere. [FULL TEXT] .
  20. Ahmed, Nesar, et al. “Solutions to blue carbon emissions: Shrimp cultivation, mangrove deforestation and climate change in coastal Bangladesh.” Marine Policy 82 (2017): 68-75.  In Bangladesh, export-oriented shrimp farming is one of the most important sectors of the national economy. However, shrimp farming in coastal Bangladesh has devastating effects on mangrove forests. Mangroves are the most carbon-rich forests in the tropics, and blue carbon (i.e., carbon in coastal and marine ecosystems) emissions from mangrove deforestation due to shrimp cultivation are accumulating. These anthropogenic carbon emissions are the dominant cause of climate change(??) which in turn affect shrimp cultivation. Some adaptation strategies including Integrated Multi-Trophic Aquaculture (IMTA), mangrove restoration, and Reducing Emissions from Deforestation and forest Degradation (REDD+) could help to reduce blue carbon emissions. Translocation of shrimp culture from mangroves to open-water IMTA and restoration of habitats could reduce blue carbon emissions, which in turn would increase blue carbon sequestration. Mangrove restoration by the REDD+ program also has the potential to conserve mangroves for resilience to climate change. However, institutional support is needed to implement the proposed adaptation strategies.
  21. Taillardat, Pierre, Daniel A. Friess, and Massimo Lupascu. “Mangrove blue carbon strategies for climate change mitigation are most effective at the national scale.” Biology letters 14.10 (2018): 20180251Carbon fixed by vegetated coastal ecosystems (blue carbon) can mitigate anthropogenic CO2 emissions, though its effectiveness differs with the spatial scale of interest. A literature review compiling carbon sequestration rates within key ecosystems confirms that blue carbon ecosystems are the most efficient natural carbon sinks at the plot scale, though some overlooked biogeochemical processes may lead to overestimation. Moreover, the limited spatial extent of coastal habitats minimizes their potential at the global scale, only buffering 0.42% of the global fossil fuel carbon emissions in 2014. Still, blue carbon plays a role for countries with moderate fossil fuel emissions and extensive coastlines. In 2014, mangroves mitigated greater than 1% of national fossil fuel emissions for countries such as Bangladesh, Colombia and Nigeria. Considering that the Paris Agreement is based on nationally determined contributions, we propose that mangrove blue carbon may contribute to climate change mitigation at this scale in some instances alongside other blue carbon ecosystems. [FULL TEXT]
  22. Kilminster, Kieryn, et al. “Seagrasses of southern and south-western Australia.” Seagrasses of Australia. Springer, Cham, 2018. 61-89The coastal waters of southern and south-western Australia are home to almost 30,000 km2 of seagrass, dominated by temperate endemic species of the genera Posidonia and Amphibolis. In this region, seagrasses are common in estuaries and sheltered coastal areas including bays, lees of islands, headlands, and fringing coastal reefs. Additionally, extensive meadows exist in the inverse estuaries of the Gulfs in South Australia, and in Shark Bay in Western Australia. This chapter explores (i) how geological time has shaped the coastline and influenced seagrasses, (ii) present day habitats and drivers, (iii) how biogeography patterns previously reported have been altered due to anthropogenic and climate impacts, and (iv) emerging threats and management issues for this region. Species diversity in this region rivals those of tropical environments, and many species have been found more than 30 km offshore and at depths greater than 40 m. Seagrasses in this region face a future of risk from multiple stressors at the ecosystem scale with coastal development, eutrophication, extreme climate events and global warming. However, our recent improved understanding of seagrass recruitment, restoration and resilience provides hope for the future management of these extraordinary underwater habitats.
  23. Wilson, Shaun, Alan Kendrick, and Barry Wilson. “The North-Western Margin of Australia.” World Seas: an Environmental Evaluation. Academic Press, 2019. 303-331.  The coastal areas and seas of north-west Australia traverse tropical and temperate latitudes, extensive ria and arid coastlines, complex inshore and offshore archipelagos and include two world heritage listed sites. As such the geological, physical environment and biodiversity of the region is extensive. The Indonesian Flow Through, and Holloway and Leeuwin currents are important moderators of temperature, vectors of propagules, and have a strong influence on the distribution of benthic communities. In turn, the El Niño southern oscillation is closely aligned to the strength of these currents and periodic disturbances that have caused widespread change to benthic communities over the past 20 years. Aboriginal people have occupied the region for > 46,000 years though European exploration only dates from the 1600s and even today human presence across much of the region is sparse. Nonetheless the region supports petroleum, shipping, tourism, fishing, and aquaculture industries of national economic significance. Human interactions with the marine environment are managed via fisheries, shipping, and threatened species legislation and the extensive network of multiple-use marine reserves.

3 Responses to "TBGY Does Blue Carbon"

TBGY = The Bald Guy on Youtube

[…] is the degradation of coastal ecosystems and their blue carbon sequestration due to human activity [RELATE POST ON BLUE CARBON] . For this reason, additional carbon sequestration that can be attributed to action taken by humans […]

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