Causes And Consequences Of Marine Organisms - 1422 Words

INTRODUCTION Anthropogenic CO2 release into the atmosphere has led to increasing temperatures in the atmosphere and in the ocean (CITA). Greater amounts of CO2 is causing the oceans to become more acidic (Caldeira Wickett, 2003; Ross et al., 2011). Oceans capacity to absorb CO2 from the atmosphere is making them become more acidic (Caldeira Wickett, 2003; Portner, 2008) Oceans’ average surface temperature are predicted to rise up to 1.5 C by 2050 and 3 C by 2100 (Donelson et al., 2011; PONER MAS CITAS), simultaneously oceans’ surface pH will decrease from a level of 8.1–8.2 by 0.3–0.5 units by 2100 (pH 7.6–7.9) and 0.7–0.77 units by 2300 (pH 7.33–7.5) (Caldeira Wickett, 2003; Donelson et al., 2011). These variations in the†¦show more content†¦Elevated temperatures aggravate oxygen limitation by leading to a higher demand of it from species and by reducing its solubility causing fish with larger individuals to be more thermally sensitive to oceans’ warming (Neuheimer et al., 2011; Pà ¶rtner, 2008; Pà ¶rtner Knust, 2006; Rodnick et al., 2004). In addition eggs and larvae of some fish species have been observed to have narrower thermal windows. In larvae this is due to their small body size, higher metabolic rate, and lower energy reserves (Pà ¶rtner Farrel, 2008; Rijnsdorp et al., 2009). If all size groups are affected within a population, abundance, recruitment success and productivity can be negatively affected (Neuheimer et al., 2011; Pà ¶rtner Knust, 2006). Some species have the capacity to acclimate to changes in temperatures. Acclimation is the organisms’ capacity to modify phenotypical traits that alter their physiology, behaviour or morphology to fit the environmental conditions (Donelson et al., 2011). According to Agilleta (2009, in Donelson et al., 2011) there are two types of acclimation, reversible and developmental. Reversible acclimation refers to the controlled responses to daily or seasonal environmental fluctuations; while developmental acclimation involves the permanent