環(huán)境生態(tài)學(xué)---第二十三章空氣、水和土壤污染物-資料下載頁
2024-10-16 14:30本頁面
【正文】 釋放的光化學(xué)煙霧生成。 3 Prior to the development of the stratospheric ozone layer which forms the ‘ozone shield’ the evolution of terrestrial life was inhibited. DNA efficiently absorbs UV light, which seriously disrupts DNA replication, causing reproductive failure and death. Relatively small increases in UV radiation can cause mutations during the replication process that may result in the production of cancerous cells. A major concern is the potential damage caused by UV light to plants. Which could reduce primary productivity, and therefore affect whole ecosystems. The importance of the ozone shield Chlorofluorocarbons (CFCs) can degrade ozone in the stratosphere. Attention was focused on the problem when the British Antarctic Survey demonstrated a strong depletion of the Antarctic ozone shield. It is estimated that a single chlorine atom can breakdown 10 000 ozone molecules. If the trend of ozone loss continues it is predicted that the ozone shield will be depleted by a further 10% by 2050。 this may lead to an additional 300 million cases of skin cancer. Stratospheric ozone depletion Related topics Solar radiation and climate (C1) Air, water and soil pollutants (W1) 臭氧屏的 重要性 在同溫層臭氧層即“臭氧屏”（ ozone shield）形成之前，陸地生物的發(fā)展受到限制。 DNA大量吸收紫外線，而紫外光會嚴(yán)重破壞 DNA的復(fù)制，導(dǎo)致繁殖的失敗和死亡。相對少量的增加紫外輻射會引起復(fù)制過程中的突變，從而導(dǎo)致癌細(xì)胞的生成。值得注意的是，紫外光對植物的重大損傷會導(dǎo)致初級生產(chǎn)力下降，因而影響整個(gè)生態(tài)系統(tǒng)。 相關(guān)主題 太陽輻射與氣候（ C1）空氣、水和土壤污染物（ W1） 平流層臭氧 缺損 含氯氟烴（ CFCs）能降解同溫層中的臭氧。當(dāng)英國南極考察團(tuán)證實(shí)南極臭氧屏出現(xiàn)嚴(yán)重缺損后，這個(gè)問題引起了重視。據(jù)估計(jì)，單個(gè)氯原子能破壞 100000個(gè)臭氧分子。如果按臭氧損失的現(xiàn)行趨勢發(fā)展下去，預(yù)計(jì)到 2050年，臭氧屏將再缺損 10%，這會增加 3億皮膚癌患者。 2021年和 2021年的臭氧空洞
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