Clarlari
Hello! I am practicing a talk page post here.
Clarlari (talk) 04:41, 19 January 2016 (UTC)clarlari
Clarlari, you are invited to the Teahouse!
editHi Clarlari! Thanks for contributing to Wikipedia. We hope to see you there!
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Welcome!
editHello, Clarlari, and welcome to Wikipedia! My name is Ian and I work with the Wiki Education Foundation; I help support students who are editing as part of a class assignment.
I hope you enjoy editing here. If you haven't already done so, please check out the student training library, which introduces you to editing and Wikipedia's core principles. You may also want to check out the Teahouse, a community of Wikipedia editors dedicated to helping new users. Below are some resources to help you get started editing.
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If you have any questions, please don't hesitate to contact me on my talk page. Ian (Wiki Ed) (talk) 19:30, 19 January 2016 (UTC)
Ideas for article
editJanan, Dan, Jeff and I are interested in some aspect of carbon sequestration in seagrasses. These terms are separate Wiki articles but there is not a page on this specific topic therefore we feel it would be a beneficial addition to the Wiki world.
Phytoplankton
editHi Clarlari. Just a quick note to explain why I reverted your change to phytoplankton. The sentence you added was not incorrect. However, in talking about light in a section largely dealing with nutrients, it was completely out of place. Perhaps consider adding a more complete treatment of light? While the section is currently all about nutrients, it's title refers to growth and light is obviously a fundamental part of this. Anyway, I hope that you're enjoying your time at Wikipedia. Happy editing and good luck with your course. Cheers, --PLUMBAGO 17:46, 26 January 2016 (UTC)
STUFF FROM DAN BELOW
Sedimentation and Blue Carbon Burial
editOrganic carbon is only sequestered from the oceanic system if it reaches the sea floor and gets covered by a layer of sediment. Reduced oxygen levels in buried environments mean that tiny bacteria who eat organic matter and respire C02 can’t decompose the carbon, so it is removed from the system permanently. Organic matter that sinks, but is not buried by a sufficiently deep layer of sediment is subject to re-suspension by changing ocean currents, bioturbation by organisms that live in the top layer of marine sediments, and decomposition by heterotrophic bacteria. If any of these things occur, then the organic carbon is put back in the system. Carbon sequestration takes place only if burial rates by sediment are greater than the long term rates of erosion, bioturbation, and decomposition.[1]
Spatial Variability in Sedimentation
editSedimentation is the rate at which floating or suspended particulate matter sinks and accumulates on the ocean floor. The faster (more energetic) the current, the more sediment it can pick up. As sediment laden currents slow, the particles fall out of suspension and come to rest on the sea floor. In other words, a fast current can pick up lots of heavy grains, where as a slow current can pick up only tiny pieces. As one can imagine, different places in the ocean vary drastically when it comes to the amount of suspended sediment and rate of deposition.[1]
Open Ocean
editThe open ocean has very low sedimentation rates because most of the terrigenous sediments that make it here are carried by the wind. Aeolian transport accounts for only a small fraction of the total sediment delivery to the oceans. Additionally, there is much less plant and animal life to be buried. Therefore, carbon burial rates are relatively slow in the open ocean.[2]
Coastal Margins
editCoastal margins have high sedimentation rates because of rivers, which account for the vast majority of sediment delivery to the ocean. In most cases, sediments are deposited near the river mouth or are transported in the alongshore direction due to wave forcing. In some places sediment falls into submarine canyons and is transported off-shelf, if the canyon is sufficiently large or the shelf is narrow. Coastal margins also contain diverse and plentiful marine species, especially in paces that experience periodic upwelling. More marine life plus higher sedimentation rates create hotspots for carbon burial.[3]
Carbon Burial in Submarine Canyons
editMarine canyons are magnets for sediment, because as currents carry sediment on the shelf in the alongshore direction, the path of the current crosses canyons perpendicularly. When the same amount of water flow is suddenly in much deeper water it slows down, and deposits sediment. Due to the extreme depositional environment, carbon burial rates in the Nazare canyon near Portugal are 30x greater than the adjacent continental slope! This canyon alone accounts for about 0.03% of global terrestrial OC burial in marine sediments. This may not seem like much, but the Nazarre submarine canyon only makes up 0.0001% of the area of the worlds oceans.[2]
Human changes to global sedimentary systems
editHumans have been modifying sediment cycles on a massive scale for thousands of years through a number of mechanisms.
Agriculture/land clearing
editWhen humans started clearing land to grow crops, they ruined the ability of the land to retain sediment. In a natural ecosystem, roots from plants hold sediment in place when it rains. Trees and shrubs reduce the amount of rainfall that impacts the dirt, and create obstacles that forest streams must flow around. When all vegetation is removed rainfall impacts directly on the dirt, there are no roots to hold on to the sediment, and there is nothing to stop the stream from scouring banks as it flows straight downhill. For many thousands of years, the net effect of humans on global sediment cycles was an increase in sedimentation due to this process.
Dams
editThe first dams date back to 3000 BC and were built to control flood waters for agriculture. When sediment laden river flow reaches a dam’s reservoir, the water slows down as it pools. Since slower water can’t carry as much sediment, virtually all of the sediment falls out of suspension before the water passes through the dam. The result is that most dams are nearly 100% efficient sediment traps. For thousands of years, there were too few dams to have a significant impact on global sedimentary cycles. The popularization of hydroelectric power in the last century has caused an enormous boom in dam building. Currently only a third of the world’s largest rivers flow unimpeded to the ocean.[4]
Channelization
editIn a natural system, the banks of a river will meander back and forth as different channels erode, accrete, open, or close. Seasonal floods regularly overwhelm riverbanks and deposit nutrients on adjascent flood plains. These services are essential to natural ecosystems, but are quite troublesome for people. Humans love to build houses and developments close to rivers, but hate watching their buildings get flooded or tumble down a bank. In response rivers in populated areas are often channelized, meaning that their banks and sometimes beds are armored with a hard material that prevents erosion and fixes them in place. This prevents erosion because there is no soft substrate left for the river to take downstream.
Impacts
editCurrently, the net effect of humans on global sedimentary cycling is a drastic reduction in the amount of sediment that makes it to the ocean. If we continue to build dams and channelize rivers, we will start to see a number of problems in coastal areas including sinking deltas, shrinking beaches, and disappearing salt marshes. In addition, it’s possible that we might ruin one of the biggest carbon sinks that we know of. Without sequestration of carbon in coastal marine sediments, we will likely see accelerated global climate change.[5]
References
edit- ^ a b Hastings, R. (2011). "A Terrestrial Organic Matter Depocenter on a High-Energy Margin Adjacent to a Low-Sediment-Yield River: The Umpqua River Margin, Oregon" (PDF). Master's Thesis, OSU, Corvallis, Oregoin. Retrieved 2/23/16.
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(help) - ^ a b Masson, D. G., Huvenne, V. A., Stigter, H. C., Wolff, G. A., Kiriakoulakis, K., Arzola, R. G., & Blackbird, S. (2010). Efficient burial of carbon in a submarine canyon. Geology, 38(9), 831-34.
- ^ Nittrouer, C. A. (2007). Continental margin sedimentation: From sediment transport to sequence stratigraphy. Malden, MA: Blackwell Pub. for the International Association of Sedimentologists.
- ^ Dandekar, P. (2012). Where Rivers Run Free. Retrieved February 24, 2016, from https://www.internationalrivers.org/resources/where-rivers-run-free-1670
- ^ "World's large river deltas continue to degrade from human activity". News Center. Retrieved 2016-02-24.
END STUFF FROM DAN
STUFF FROM MARCUS BELOW
Algae
editBoth macroalgae and microalgae are being investigated as possible means of carbon sequestration[1].[2][3][4] Because algae lack the complex lignin associated with terrestrial plants, the carbon in algae is released into the atmosphere more rapidly than carbon captured on land[5].[3] Algae have been proposed as a short-term storage pool of carbon that can be used as a feedstock for the production of various biogenic fuels. Microalgae are often put forth as a potential feedstock for carbon-neutral biodiesel and biomethane production due to their high lipid content.[1] Macroalgae, on the other hand, do not have high lipid content and have limited potential as biodiesel feedstock, although they can still be used as feedstock for other biofuel generation.[3] Macroalgae have also been investigated as a feedstock for the production of biochar. The biochar produced from macroalgae is higher in agriculturally important nutrients than biochar produced from terrestrial sources.[4] Another novel approach to carbon capture which utilizes algae is the Bicarbonate-based Integrated Carbon Capture and Algae Production Systems (BICCAPS) developed by a collaboration between Washington State University in the United States and Dalian Ocean University in China. Many cyanobacteria, microalgae, and macroalgae species can utilize carbonate as a carbon source for photosynthesis. In the BICCAPS, alkaliphilic microalgae utilize carbon captured from flue gases in the form of bicarbonate[6][7]. In South Korea, macroalgae have been utilized as part of a climate change mitigation program. The country has established the Coastal CO2 Removal Belt (CCRB) which is comprised of artificial and natural ecosystems. The goal is to capture carbon using large areas of kelp forest.[8]
Ecosystem Restoration
editRestoration of mangrove forests, seagrass meadows, marshes, and kelp forests has been implemented in many countries[8][9][10]. These restored ecosystems have the potential to act as carbon sinks. Restored seagrass meadows were found to start sequestering carbon in sediment within about four years. This was the time needed for the meadow to reach sufficient shoot density to cause sediment deposition.[10] Similarly, mangrove plantations in China showed higher sedimentation rates than barren land and lower sedimentation rates than established mangrove forests. This pattern in sedimentation rate is thought to be a function of the plantation’s young age and lower vegetation density.[9]
Factors Influencing Blue Carbon Burial Rates
editDensity of Vegetation
editThe density of vegetation in mangrove forests, seagrass meadows, and tidal marshes is an important factor in carbon burial rates.[10][9] The density of the vegetation must be sufficient to change water flows enough to reduce erosion and increase sediment deposition.[11][10]
Nutrient Load
editIncreases in carbon capture and sequestration have been observed in both mangrove and seagrass ecosystems which have been subjected to high nutrient loads, either intentionally or due to waste from human activities.[12] Intentional fertilization has been used in seagrass meadow restoration. Perches for seabirds are installed in the meadow and the bird droppings are the fertilizer source. The fetrilization allows fast growing varieties of seagrasses to establish and grow. The species composition of these meadows is markedly different than the original seagrass meadow, although after the meadow has been reestablished and fertilization terminated, the meadows return to a species composition that more closely resembles an undisturbed meadow.[13] Research done on mangrove soils from the Red Sea have shown that increases in nutrient loads to these soils do not increase carbon mineralization and subsequent CO2 release.[14] This neutral effect of fertilization was not found to be true in all mangrove forest types. Carbon capture rates also increased in these forests due to increased growth rates of the mangroves. In forests with increases in respiration there were also increases in mangrove growth of up to six times the normal rate.[15]
- REDIRECT Clarlari/sandbox
References
edit- ^ a b Kumar, K., Dasgupta, C. N., Nayak, B., Lindblad, P., & Das, D. (2011). Development of suitable photobioreactors for CO 2 sequestration addressing global warming using green algae and cyanobacteria. Bioresource technology, 102(8), 4945-4953.
- ^ Kumar, K., Banerjee, D., & Das, D. (2014). Carbon dioxide sequestration from industrial flue gas by Chlorella sorokiniana. Bioresource technology,152, 225-233.
- ^ a b c Chung, I. K., Beardall, J., Mehta, S., Sahoo, D., & Stojkovic, S. (2011). Using marine macroalgae for carbon sequestration: a critical appraisal.Journal of Applied Phycology, 23(5), 877-886.
- ^ a b Bird, M. I., Wurster, C. M., de Paula Silva, P. H., Bass, A. M., & De Nys, R. (2011). Algal biochar–production and properties. Bioresource technology,102(2), 1886-1891.
- ^ Mcleod, E., Chmura, G. L., Bouillon, S., Salm, R., Björk, M., Duarte, C. M., ... & Silliman, B. R. (2011). 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), 552-560.
- ^ Chi, Z., O’Fallon, J. V., & Chen, S. (2011). Bicarbonate produced from carbon capture for algae culture. Trends in biotechnology, 29(11), 537-541.
- ^ Chi, Z., Xie, Y., Elloy, F., Zheng, Y., Hu, Y., & Chen, S. (2013). Bicarbonate-based integrated carbon capture and algae production system with alkalihalophilic cyanobacterium. Bioresource technology, 133, 513-521.
- ^ a b Chung, I. K., Oak, J. H., Lee, J. A., Shin, J. A., Kim, J. G., & Park, K. S. (2013). Installing kelp forests/seaweed beds for mitigation and adaptation against global warming: Korean Project Overview. ICES Journal of Marine Science: Journal du Conseil, fss206.
- ^ a b c Zhang, J. P., Cheng-De, S. H. E. N., Hai, R., Jun, W. A. N. G., & Wei-Dong, H. A. N. (2012). Estimating change in sedimentary organic carbon content during mangrove restoration in southern China using carbon isotopic measurements. Pedosphere, 22(1), 58-66.
- ^ a b c d Greiner, J. T., McGlathery, K. J., Gunnell, J., & McKee, B. A. (2013). Seagrass restoration enhances “blue carbon” sequestration in coastal waters. PloS one, 8(8), e72469.
- ^ Hendriks, I. E., Sintes, T., Bouma, T. J., & Duarte, C. M. (2008). Experimental assessment and modeling evaluation of the effects of the seagrass Posidonia oceanica on flow and particle trapping.
- ^ Kuwae, T., Kanda, J., Kubo, A., Nakajima, F., Ogawa, H., Sohma, A., & Suzumura, M. (2015). Blue carbon in human-dominated estuarine and shallow coastal systems. Ambio, 1-12.
- ^ Herbert, D. A., & Fourqurean, J. W. (2008). Ecosystem structure and function still altered two decades after short-term fertilization of a seagrass meadow. Ecosystems, 11(5), 688-700.
- ^ Keuskamp, J. A., Schmitt, H., Laanbroek, H. J., Verhoeven, J. T., & Hefting, M. M. (2013). Nutrient amendment does not increase mineralisation of sequestered carbon during incubation of a nitrogen limited mangrove soil.Soil Biology and Biochemistry, 57, 822-829.
- ^ Lovelock, C. E., Feller, I. C., Reef, R., & Ruess, R. W. (2014). Variable effects of nutrient enrichment on soil respiration in mangrove forests. Plant and soil, 379(1-2), 135-148.
END STUFF FROM MARCUS