Effect of Ocean Acidification Upon Ability to Genetically Adapt in Nereis Species - Report Example

Effect of Ocean Acidification upon Ability to Genetically Adapt in Nereis Species The physiological and life history performance of ectotherms are determined by the body’s metabolic rate. This means that metabolic rates are very much sensitive for the ability of an organism to survive in a new environment. Some of organisms can survive when exposed to high levels of Carbon IV Oxide in the form of p this study helps to shed light on the CO2. We carried out a series of experiments using several tolerant and sensitive polychaete species living in natural CO2 vent system. Several research activities have showed that certain species of polychaete worms have the ability to modify and alter their metabolic rates so as to enable them cope up with waters in high carbon dioxide (CO2) which is poisonous and able to kill other closely-related species. The study explores robustness of some marine species such as polychaete worms as well as their resilience of marine biodiversity incase atmospheric carbon dioxide continues to cause much ocean acidification.The following sensitive and tolerant species of polychaete worms that live underwater in places of elevated carbon dioxide (pCO2) were studied: Nereis succinea, Nereis diversicolor, Nereis virens, Platyneire sdemerilli and Nereis zonata. These worms were collected from different areas. Some samples were from Ischia region, a place with low pH value due to CO2 vents. These individuals were exposed to low pH value environments for short time and long-term durations. The control group was set in normal pH environment. The responses of the worms were monitored and it was found out that the worms were physiologically and genetically adapted to living in extreme acidic conditions whereas others were able to adjust their metabolic rates for survival. Introduction Ocean acidification refers to the significant and detrimental dangers of surplus carbon dioxide in the atmosphere that is unseen or even its effects are not seen just because its consequences are taking place underwater. Ocean acidification is also dubbed as the ‘climate change’s equally evil twin’. Quarter of CO2 is released by burning coal, gas and oil does not stay in air for long, instead it dissolves into oceans. Since the time when the industrial era began, oceans have on averagely absorbed around 525 billion tons of CO2 Previously existent the atmosphere. Presently the number stands at around 22 million tons per day. The increased levels of carbon dioxide in recent years have led to drastic reduction of PH of ocean waters. Water absorbs CO2 from the atmosphere and forms carbonic acid, which increases H+ ions thus reducing the PH value. This leads to increased acidity, which affects the ocean’s ecosystems meaning that the oceans’ species must adapt to the increased acidity for survival either phenotypically or genotypically. Most of the marine species have to adapt to such changes for them to counter the negative effects on their physiology. The changes may be termed as phenotypic in the short term and genotypic for the long run. When CO2 dissolves in the ocean water, the waters gets more acidic. Though the ocean is immense, large amounts of carbon dioxide always have a major impact (Olive 1995, 79). Nereis is a genus that belongs to the polychaete worms in the family Nereidae. This genus comprises of many species in which most of them are marine such as the sandworm (Nereis Virens) and another common warm called the Nereis Succinea. The genus Nereis has setae and parapodia which are used for locomotion. Global warming and increased composition of CO2 in the atmosphere causes the oceans to warm and decrease in PH thus increasing the level of acidity. These stressors have disastrous effects on marine life. Increased temperatures cause a pervasive effect on metabolism until dangerous levels are reached whereas ocean acidification causes a major threat to marine life since it exerts a direct PH effect on the physiology of the marine animals. The seawater absorbs CO2 when chemical reactions take place reducing the PH of water in the oceans. It also reduces the concentration of carbonate ions and saturation of important calcium carbonate minerals. These chemical reactions are the ones referred to as ocean acidification. Calcium carbonate minerals are the main building blocks for shells and skeletons of such marine organisms. Continued ocean acidification causes many parts of the ocean to be under saturated with this mineral, which means that the organisms will not be able to produce and maintain their shells normally (Hendriks et al 2010, 160) Climatic alterations are not considered as the only consequence of increased atmospheric carbon dioxide. A high density of CO2 in the air increases the pressure of CO2 (pCO2) partially on the surface of waters thus reducing the PH of the open waters and this leads to increased ocean acidification (Wood & Widdicombe 2008, 1767). CO2 level in the air increase at a firm rate because of the increased use of carbon dioxide-releasing processes. These process include; burning of fossil fuels, deforestation, and cement product among others. At first, many scientists thought that the concept of CO2 absorption by the oceans from the atmosphere might be a good thing as it Lessen CO2 concentration in the air, which has an effect on global warming. Nonetheless, this effect has been detrimental to marine life (Olive 1995, 80) Nereis succinea species increases the rates of their biological processes such as the rates of metabolism and the ability to calcify to compensate for the increased acidity of seawater. However, the processes of increased metabolic rates and ability to calcify always comes at a substantial cost especially muscle wastage, thus these processes are unlikely to sustained in the end. Experiment A test was carried out to tell the effects of exposure of the above five species to different levels of acidified seawater on their structure, burrows, and sediment nutrient fluxe. Each warm was exposed to acidified seawater of different PH levels of 7, 6 and 5 using carbon dioxide (Portner 2008, 203). These treatments were a complete representation of the effects of ocean acidification which has a PH value of approximately 7 whereas the other PH values (6 and 5) represent a leakage from a sub-seabed carbon dioxide storage site (Dupont et al 2010, 440). The vent population of each of the species in elevated levels of CO2 was genetically and physiologically different from the nearby species that experience low levels of carbon dioxide in the form of pCO2. The body sizes for the species in the two environments were also different. This means that in high levels of carbon dioxide, the organisms have to adapt and acclimatize to the increased acidification. This processes of adaptation use energy and that is why the sizes of the organisms reduce. In addition, these species showed reduced or increased rates of metabolism when exposed in acute elevated levels of carbon dioxide (Hendriks et al 2010, 157). Metabolic rate has been considered as the most basic of all existing biological rates since they set the rate of uptake of resources and allocation to growth, survival and reproduction thus controlling their ecological processes. The rates of metabolism enables the Nereis species to preserve enough levels of energy when exposed to such environmental challenges is fundamental for survival and distribution. That is why in the experiment, the five specimens were able to survive, though in the long run, they may tend to become weak and small in size due to the energy lost during the process of metabolism and acclimatization. Metabolic depression is thus considered as a short term strategy since in the long term, metabolism may be costly due to the excessive energy required for growth, reproduction and performances which affects the fitness of the organisms. Though they may not die, they definitely grow weak (Arnold et. al 2009, 3087). The carbon dioxide vents of Ischia in Italy were used in the experiment extensively to investigate the consequences of elevated levels of pCO2 and low PH conditions on marine species, in this case, the Nereis species, as well as predict the possible responses of marine organisms to increased ocean acidification. Such species living in these conditions are considered to be tolerant. The control experiment, conducted in normal PH conditions of 7, showed that the rates of metabolism were not increased because the levels of pCO2 were low and in normal conditions. The species did not reduce in size, unlike when they were exposed to low PH values of 6 and 5. The five specimens were exposed to the various conditions for 5 days from where their body masses were measured from an incubator after the 5 days. Results It was found out that the body weights had significantly changed except for the specimens in the control process where they were exposed to normal levels of PH and Carbon dioxide. For the specimens placed in the lowest PH value of 5, it was found out that they had lost the maximum weight in terms of energy lost in the process of metabolism which was responsible for survival in such extreme condition. The specimens placed in the PH value of 6 had slightly higher weight that the ones placed in the PH value of 6. This is because in low PH values, there is a lot of ocean acidification, a condition which proves to be harmful for marine life. The species in this condition had to alter their rates of metabolism which requires a lot of energy thus reducing their weight and body masses (Portner 2008, 205). It is vital noting that no mortality for any of the test species during the process of collection, experimentation and analysis. All the five polychaetes appeared in good health after experimentation regardless of the weight losses. They were actively moving from the experimental chamber to the incubation chambers and even food traces could be seen in the digestive system. This means that the results were accurate and only measured the correct body weight loss which corresponded to the energy used during the process of metabolism (Hendriks et al 2010, 157) The results of the study show that adaption and plasticity are very much key for certain species to survive in marine biodiversity thus preventing extinction in the face of the current ongoing ocean acidification. These two adaptive strategies by marine species have largely contributed to the fate of marine biodiversity. The results also revealed that those species normally found inside the carbon dioxide vent were able to regulate the rates of metabolism when exposed to high carbon dioxide levels whereas those found outside the carbon dioxide vent were seen to be impaired by the acidic conditions in the waters. Despite the fact that some marine species are able to metabolically adapt and adjust to such extreme conditions found in acidic waters, there are other species, which cannot physiologically tolerate such conditions. The findings from this study helps in explaining mass extinctions of the past as well as any potential extinctions in the future. These findings also help in shedding the light on the resilient natures of certain species to the on-going ocean acidification (Portner 2008, 206). Conclusion It has been noted that most of polychaete species are able physiologically and genetically adapt and acclimatize to extremely elevated levels of carbon dioxide in the form of pCO2. Polychaete worms are able to survive in extreme acidic conditions just due to their ability to alter the rates of metabolism. The process of metabolism produces energy necessary for use in such conditions. For this reason, it was recorded that the specimens in the experiment lost some amounts of body weight during the whole process. Nonetheless, such adaptations in marine polychaete worms are not ubiquitous in all species that are tolerant to extreme acidic conditions found in the CO2 vents even when they live in the same ecosystems. There are other strategies used by other marine organisms so as to survive in such conditions. Such strategies include down regulation of their metabolic rates (Dupont et al 2010, 445). Ocean acidification is considered as a new field of research with studies being conducted all over the globe so as to determine its effects on marine life. This issue has gained momentum in the eyes of to policy makers, scholars and other international leaders as well as the media and several research activities show that there is still much to be understood on the same issue, how it affects marine environments as well as the subsequent consequences on the society (Wood et al 2008, 1770). The interpretations of several research activities have showed that most of the organisms that respond to elevated levels of carbon dioxide are calcifiers. This has been considered as a form of bias in the studies and has been considered as important because the overall direction and intensity of most of the metabolic responses to elevated levels of carbon dioxide are mostly affected by the regulation of calcium carbon deposition upwards. In this study, we dealt on non-calcifiers. The high levels of ocean acidification have led to the urgent need of investigating the physiological and acclimatory potential and adaptation of a range of species within the marine environment. It should also be noted that non-calcifying ectotherms which represent the recent developments in the oceanic acidity adaptation (Portner 2008, 205). This paper has helped shed the light on the different ways in which marine organisms adapt and acclimatize to the current high levels of ocean acidification. It is thus recommended that additional research be conducted so as to substantially compare further levels and rates of adaptability in most of the organisms in marine environments. Ocean acidification is very much detrimental to marine life, thus further research is necessary to determine and differentiate between the organisms, which survive, and the ones, which cannot survive at all. . Reference List Arnold, K.E., Findlay, H.S., Spicer, J.I., Daniels, C.L. & Boothroyd, D. 2009. 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