在20年的实地实验中,C3与C4草对高CO2的反应发生了意想不到的逆转
Peter B Reich1,2, Sarah E Hobbie3, Tali D Lee4
1Department of Forest Resources, University of Minnesota, St. Paul, MN 55108, USA. preich@umn.edu.
概括
植物对二氧化碳 (eCO2) 的反应会随着时间的推移而发生变化. 最初,C3工厂从eCO2中获益更多,但后来,C4工厂表现出更强的反应,挑战了现有的模式.
科学领域:
- 植物生理学
- 生态学
- 全球变化生物学
背景情况:
- 与C3植物相比,C4植物对高二氧化碳 (eCO2) 的反应通常较低.
- 这种C3-C4对比是植物学中已久的概念.
研究的目的:
- 研究植物对eCO2的长期反应.
- 在持续的eCO2条件下测试当前的C3-C4对比模式.
主要方法:
- 一个20年的空气二氧化碳丰富实验涉及88个草原.
- 在环境和eCO2下监测C3和C4地块中的生物质和土壤矿化率.
主要成果:
- 生物质对eCO2的反应最初有利于C3植物,然后在实验期间转向C4植物.
- 土壤矿化率呈现出相互转变,影响生物质反应.
- 观察到的逆转挑战了已建立的C3-C4eCO2反应范式.
结论:
- 植物对eCO2的长期反应可能与短期预测有很大差异.
- 在eCO2反应中,C3-C4对比度不是静态的,可以随着时间的推移而逆转.
- 了解动态反应对于预测全球变化的生态系统变化至关重要.
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