每个人都应该为地球尽一份力

What if we had a machine that soaked up carbon from the atmosphere? A device that would lock up CO2 for a long time. Of course, it would have to be environmentally friendly. It would also have to be efficient, reliable, cheap and easy to produce. Here’s what it might look like. Trees and forests play a crucial role in regulating our climate. Through photosynthesis they remove CO2 from the atmosphere, binding it and storing the carbon as wood. The carbon is held in the forest biomass – in the trunks, branches, foliage, and roots and in the soil as organic carbon. The process is constant and is going on all around us. In young forests, carbon is soaked up, or sequestered, quickly. In mature forests sequestration slows and is eventually is almost equaled by decomposition. The carbon balance changes little from year to year. At this point the forest doesn’t absorb much carbon but has become a vast carbon reservoir.But if the trees are destroyed, they release carbon into the atmosphere thus becoming a source of greenhouse gas emissions.

Forests cover almost one third of the world’s total land area.They account for 90 percent of the annual interchange of carbon between the atmosphere and the land.The carbon stored in these ecosystems is the equivalent of about 4.5 trillion tons of CO2.That’s more than the total carbon contained in the world’s remaining oil stocks. More, in fact, than the total amount of carbon in the atmosphere itself. So it’s no surprise that forests can be a big part of the answer to the problem of climate change. But forested lands are being lost worldwide. The pace of deforestation, mainly due to human population growth, has accelerated in recent decades.

The Forest Service works with partners in many parts of the world to promote sustainable forestry practices. Here in the United States, the Forest Service has three main roles in responding to climate change.