Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere
Plants reduce C02 to molecular species of increasing energy content. These compounds are then moved by heterotrophic organisms through decreasing energy levels as the organic matter is returned to inorganic form by successive oxidations. Thus, C02 and 02 are the major substrates of biospheric reacti...
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ftubarceojs:oai:revistes.ub.edu:article/34337 2023-05-15T16:39:22+02:00 Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere Peñuelas, Josep 2018-11-26 application/pdf http://revistes.ub.edu/index.php/oecologiaaquatica/article/view/34337 eng eng Universitat de Barcelona http://revistes.ub.edu/index.php/oecologiaaquatica/article/view/34337/33785 http://revistes.ub.edu/index.php/oecologiaaquatica/article/view/34337 Drets d'autor (c) 2021 Oecologia aquatica Oecologia aquatica; Vol. 10 No 10 (1991); 367 - 385 2604-7810 0210-9352 Carbon dioxide oxygen biogeochemical cycles biosphere info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2018 ftubarceojs 2022-12-26T14:17:12Z Plants reduce C02 to molecular species of increasing energy content. These compounds are then moved by heterotrophic organisms through decreasing energy levels as the organic matter is returned to inorganic form by successive oxidations. Thus, C02 and 02 are the major substrates of biospheric reactions. Oxygen is toxic for anaerobic and, in excess, for aerobic organisms. Its toxicity is overcome by aerobic organisms by using it as an electron terminal acceptor in respiration and by developing biochemical defenses. It still determines phenomena such as anaerobiosis, the depth limit of higher aquatic plants, or bioluminiscence, and perhaps others like the diurnal vertical rnigration of zooplankton. Low photosynthetic efficiency in light use, shape and color of vegetation may result from the peculiar availability of light and C02. Therefore, slight changes in these factors would produce life shapes deeply alien to the world we now perceive. Atmospheric C02 levels have increased by about 70 Ilmol mor 1 over the past 240 years, as has been shown by ice core studies and Mauna Loa data. Parallel to this increase, sorne plant changes have already been found: an overall decrease from 121 % to the present-day 1 00% level in stomatal density, and from 144 % to present-day 1 00% leaf nitrogen content of 14 herbarium specimens of trees, shrubs and herbs collected over the last 240 years in Catalonia, a Mediterreanean area. Similar declines have also been reported in experimental studies on leaves of plants grown in enriched CÜ2 environments. Consequently the C/N ratio has increased in leaves which together with the decrease in the specific leaf area (SLA) may have consequences for herbivores, decomposers and ecosystems. Increases in oxygen-derived compounds, mainly ozone, have potentially large biospheric effects. Nowadays, they seem to play an important role in forest decline and sorne decreased crop productions, as has been shown in laboratory experiments. Increased photosynthetic rates are expected with increasing C02 ... Article in Journal/Newspaper ice core Revistes Científiques de la Universitat de Barcelona |
institution |
Open Polar |
collection |
Revistes Científiques de la Universitat de Barcelona |
op_collection_id |
ftubarceojs |
language |
English |
topic |
Carbon dioxide oxygen biogeochemical cycles biosphere |
spellingShingle |
Carbon dioxide oxygen biogeochemical cycles biosphere Peñuelas, Josep Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
topic_facet |
Carbon dioxide oxygen biogeochemical cycles biosphere |
description |
Plants reduce C02 to molecular species of increasing energy content. These compounds are then moved by heterotrophic organisms through decreasing energy levels as the organic matter is returned to inorganic form by successive oxidations. Thus, C02 and 02 are the major substrates of biospheric reactions. Oxygen is toxic for anaerobic and, in excess, for aerobic organisms. Its toxicity is overcome by aerobic organisms by using it as an electron terminal acceptor in respiration and by developing biochemical defenses. It still determines phenomena such as anaerobiosis, the depth limit of higher aquatic plants, or bioluminiscence, and perhaps others like the diurnal vertical rnigration of zooplankton. Low photosynthetic efficiency in light use, shape and color of vegetation may result from the peculiar availability of light and C02. Therefore, slight changes in these factors would produce life shapes deeply alien to the world we now perceive. Atmospheric C02 levels have increased by about 70 Ilmol mor 1 over the past 240 years, as has been shown by ice core studies and Mauna Loa data. Parallel to this increase, sorne plant changes have already been found: an overall decrease from 121 % to the present-day 1 00% level in stomatal density, and from 144 % to present-day 1 00% leaf nitrogen content of 14 herbarium specimens of trees, shrubs and herbs collected over the last 240 years in Catalonia, a Mediterreanean area. Similar declines have also been reported in experimental studies on leaves of plants grown in enriched CÜ2 environments. Consequently the C/N ratio has increased in leaves which together with the decrease in the specific leaf area (SLA) may have consequences for herbivores, decomposers and ecosystems. Increases in oxygen-derived compounds, mainly ozone, have potentially large biospheric effects. Nowadays, they seem to play an important role in forest decline and sorne decreased crop productions, as has been shown in laboratory experiments. Increased photosynthetic rates are expected with increasing C02 ... |
format |
Article in Journal/Newspaper |
author |
Peñuelas, Josep |
author_facet |
Peñuelas, Josep |
author_sort |
Peñuelas, Josep |
title |
Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
title_short |
Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
title_full |
Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
title_fullStr |
Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
title_full_unstemmed |
Effects of increasing levels of C02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
title_sort |
effects of increasing levels of c02 and 02 derived compounds on biogeochemical cycles and shaping of the biosphere |
publisher |
Universitat de Barcelona |
publishDate |
2018 |
url |
http://revistes.ub.edu/index.php/oecologiaaquatica/article/view/34337 |
genre |
ice core |
genre_facet |
ice core |
op_source |
Oecologia aquatica; Vol. 10 No 10 (1991); 367 - 385 2604-7810 0210-9352 |
op_relation |
http://revistes.ub.edu/index.php/oecologiaaquatica/article/view/34337/33785 http://revistes.ub.edu/index.php/oecologiaaquatica/article/view/34337 |
op_rights |
Drets d'autor (c) 2021 Oecologia aquatica |
_version_ |
1766029703816151040 |