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Do you know forests are one of our planet's greatest carbon sinks? This means that they absorb an enormous amount of carbon released into the atmosphere, a greenhouse gas that contributes to climate change and the earth's rising temperature.

The poplar tree, standing tall and regal, is known for its fast-growing nature and its gray, white, or black bark. A biotechnology firm in San Francisco, CA, genetically modified poplar trees. According to a four-month study conducted in their greenhouse, the engineered trees grew 53% larger than their normal counterparts and stored 27% more CO2. In February 2023, the company also planted modified poplar trees in southern Georgia. This marks the first time in the United States that engineered trees have been planted outside of a controlled lab setting!

All plants experience photosynthesis（光合作用），where sunlight，water，and CO2 are transformed into glucose and oxygen. However, almost all trees release a poisonous substance in the process. To remove this substance, trees must use up newly-produced energy in another step known as photo-respiration（光呼吸作用）， which does not produce any energy and releases CO2 back into the atmosphere. To prevent plants from wasting their energy, the biotechnology firm engineered their poplar trees with genes found in green algae. First tested in tobacco plants, the foreign genes change the poisonous substance produced by trees into sugars, so that more energy can be used for removing carbon and tree growth.

Researchers from the company are planting their poplar trees on private land that has been previously disturbed, such as abandoned coal mines in Pennsylvania. The modified trees will be planted between natives like sweet gum and bald cypress to boost biodiversity and maintain soil fertility（肥沃）.

Plant biologist Norberto Martinez from the University of Illinois suggests the engineered poplar trees may not thrive outdoors or will require more water and fertilizer to maintain their fast growth. Many sustainable forestry organizations have also banned engineered trees from being planted in forests. The Global Justice Ecology Project argued that these trees could interfere with efforts to protect and regenerate forests.

Though there may be opposing opinions regarding genetically modified poplar trees, one thing is for sure: they hold the potential to lower greenhouse gases in our environment at a faster rate. This company's attempt is certainly an innovative approach to the ongoing climate crisis.