This study examined the literature in ISI Web of Science to identify the effects that the main drivers of global change have on the nutrient concentrations and C:N:P stoichiometry of organisms and ecosystems, and examined their relationship to changes in ecosystem structure and function. We have conducted a meta-analysis by comparing C:N:P ratios of plants and soils subjected to elevated [CO2] with those subjected to ambient [CO2]. A second meta-analysis compared the C:N:P ratios of plants and soils that received supplemental N to simulate N deposition and those that did not receive supplemental N. On average, an experimental increase in atmospheric [CO2] increased the foliar C:N ratios of C3 grasses, forbs, and woody plants by 22%, but the foliar ratios of C4 grasses were unaffected.
This trend may be enhanced in semi-arid areas by the increase in droughts that have been projected for the coming decades which can increase leaf C:N ratios. The available studies show an average 38% increase in foliar C:P ratios in C3 plants in response to elevated atmospheric [CO2], but no significant effects were observed in C4 grasses. Furthermore, studies that examine the effects of elevated atmospheric [CO2] on N:P ratio (on a mass basis) are warranted since its response remains elusive. N deposition increases the N:P ratio in the plants of terrestrial and freshwater ecosystems, and decreases plants and organic soil C:N ratio (25% on average for C3 plants), reducing soil and water N2 fixation capacity and ecosystem species diversity. In contrast, in croplands subjected to intense fertilization, mostly, animal slurries, a reduction in soil N:P ratio can occur because of the greater solubility and loss of N. In the open ocean, there are experimental observations showing an ongoing increase in P-limited areas in response to several of the factors that promote global change, including the increase in atmospheric [CO2] which increases the demand for P, the warming effect that leads to an increase in water column stratification, and increases in the N:P ratio of atmospheric inputs. Depending on the type of plant and the climate where it grows, warming can increase, reduce, or have no effect on foliar C:N ratios. The results suggest that warming and drought can increase C:N and C:P ratios in warm-dry and temperate-dry terrestrial ecosystems, especially, when high temperatures and drought coincide. Advances in this topic are a challenge because changes in stoichiometric ratios can favour different types of species and change ecosystem composition and structure.
Terms of Use: This is an academic paper. Students should NOT copy our materials word to word, as we DO NOT encourage Plagiarism. Only use as a guide in developing your original research work. Thanks.
Disclaimer: All undertaking works, records, and reports posted on this website, eprojectguide.com are the property/copyright of their individual proprietors. They are for research reference/direction purposes and the works are publicly supported. Do not present another person’s work as your own to maintain a strategic distance from counterfeiting its results. Use it as a guide and not duplicate the work in exactly the same words (verbatim). eprojectguide.com is a vault of exploration works simply like academia.edu, researchgate.net, scribd.com, docsity.com, course hero, and numerous different stages where clients transfer works. The paid membership on eprojectguide.com is a method by which the site is kept up to help Open Education. In the event that you see your work posted here, and you need it to be eliminated/credited, it would be ideal if you call us on +2348064699975 or send us a mail along with the web address linked to the work, to eprojectguide@gmail.com. We will answer to and honor each solicitation. Kindly note notification it might take up to 24 – 48 hours to handle your solicitation.