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对黔桂地区７条晚二叠世碳酸盐岩型煤系剖面进行了碳酸盐岩碳氧同位素测定，发现晚二叠世吴家坪阶与长兴阶碳酸盐岩的δ１３Ｃ值有明显差异，前者δ１３Ｃ多大于３．０‰，后者多小于３．０‰，进一步对晚二叠世δ１３Ｃ的变化原因的分析表明，δ１３Ｃ的变化可能与晚古生代末期聚煤作用的减弱密切相关，后者造成自然界碳库中的１２Ｃ的富集，从而使得海水以及在其中沉淀出的碳酸盐岩中的δ１３Ｃ值降低。此外，植物光合作用从大气中吸收ＣＯ２的量也随陆地植被减少而减少，结果造成大气中的ＣＯ２的大量富集，从而进一步产生温室效应，制约生物界的发展。联系到这一阶段生物界的衰亡灭绝，可以认为温室效应是晚二叠世生物逐渐衰亡及晚二叠世末群体灭绝的主要原因之一。
Carbonate and oxygen isotopic measurements of carbonate rocks in seven Late Permian carbonate coal measures in the Guizhou-Guangxi region show that δ13C values of the Wujiaping and Changxing Member carbonate rocks in the Late Permian are significantly different, The former δ13C is more than 3.0 ‰ and the latter less than 3.0 ‰. Further analysis of the causes of δ13C in the Late Permian shows that the δ13C change may be closely related to the weakened coal accumulation in the late Paleozoic, Resulting in the accumulation of 12C in the carbon pool of nature, resulting in a reduction of δ13C values in seawater and in the carbonate rocks precipitated therein. In addition, the amount of photosynthesis CO2 absorbed from the atmosphere also decreases with the reduction of terrestrial vegetation. As a result, a large amount of CO2 is enriched in the atmosphere, further contributing to the greenhouse effect and restricting the development of the biological world. In connection with the decline and extinction of the biosphere at this stage, it can be considered that the greenhouse effect is one of the major causes of the late Permian biological decline and the population extinction in late Permian.