Long-term experiments show unexpected plant responses to elevated CO2 concentrations Rising carbon dioxide (CO2) concentrations in the atmosphere as a result of fossil fuel burning are expected to fertilize plants, resulting in faster growth. However, this change is not expected to be the same for all plants. Rather, scientists believe that differences in photosynthetic mechanism favor one plant group—the C3 plants—over the other, the C4 plants. On page 317 of this issue, Reich et al. (1) show that, although this expectation is met in the first few years of a long-term experiment, the situation reverses after 15 to 20 years, with important implications for future crop production and ecosystems.

中文翻译：

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植物对二氧化碳的反应是一个时间问题

长期实验表明，植物对 CO2 浓度升高的反应出乎意料 化石燃料燃烧导致大气中二氧化碳 (CO2) 浓度升高，预计会使植物受精，从而加快生长。然而，这种变化预计不会对所有植物都相同。相反，科学家认为光合作用机制的差异有利于一个植物群——C3 植物——而不是另一个 C4 植物。在本期第 317 页上，Reich 等人。(1) 表明，虽然这一预期在长期试验的前几年得到满足，但在 15 到 20 年后情况发生逆转，对未来的作物生产和生态系统具有重要意义。