{"id":1936,"date":"2019-12-10T11:25:31","date_gmt":"2019-12-10T09:25:31","guid":{"rendered":"http:\/\/klima-fakten.net\/?page_id=1936"},"modified":"2021-09-07T20:03:08","modified_gmt":"2021-09-07T19:03:08","slug":"greening-the-earth-2","status":"publish","type":"page","link":"https:\/\/klima-fakten.net\/?page_id=1936&lang=en","title":{"rendered":"Greening the earth"},"content":{"rendered":"
\"image_print\"<\/a><\/div>\n

Carbon dioxide as a „good greenhouse gas“<\/h4>\n\n\n\n

plants need CO2<\/sub> as a basic prerequisite for photosynthesis. The so-called C3<\/sub>-plants<\/a> ( most plants of the middle latitudes, useful plants like e.g.B. wheat, rye or rice<\/strong>) perform different compared to the C4<\/sub>-plants<\/a> (typically grasses, crops such as corn, sugar cane or millet<\/strong>):<\/p>\n\n\n\n

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dependence of CO2<\/sub>dependence of CO2<\/sub>-concentration <\/figcaption><\/figure>\n\n\n\n

This diagram<\/a> shows that plants can better absorb CO<\/strong>2<\/strong><\/sub> the higher their concentration in the air is<\/strong>. For C4<\/sub> plants, the optimal absorption capacity is already almost reached at the — current — CO2<\/sub> concentration of about 400 ppm, while C3<\/sub> plants „feel better“ at much higher concentrations of 800-1000 ppm. Therefore, greenhouses are enriched with CO2<\/sub> to improve plant growth. The diagram also shows that a CO<\/strong>2<\/strong><\/sub>concentration below 150 ppm would mean the end of all life<\/strong>. <\/p>\n\n\n\n

\"\"\/<\/figure>\n\n\n\n

Satellite measurements were used to determine the effects of increased CO<\/a>2<\/a><\/sub>-concentration on global plant growth<\/a>, with the astonishing result that between 1982 and 2009 the greening of the soil increased by 25-50%, 70% of which was due to the increase in CO<\/strong>2<\/strong><\/sub>>. In particular, parts of the earth’s arid regions have become greener<\/strong>. This can be explained by the fact that the openings of the leaves to the inlet of CO2<\/sub> (Stomata<\/a>) are the same as the openings through which the water evaporates. The more CO2<\/sub> is present, the less stomata have to be opened and the plant becomes more resistant to drought.
This film from a NASA publication from the year 2016<\/a> shows the essential connections briefly and vividly:<\/p>\n\n\n\n

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