All of this makes the net benefit of reforestation extremely difficult to measure .
所有这一切都使得重新造林的纯利益极难估算。
Even if we are making progress elsewhere on air pollution , water pollution , or reforestation , what difference does it make when we are overheating the planet ?
We have planted hundreds of thousands of young trees on public lands in all 50 states of the united states and in theinternational tree planting countries as part of their reforestation programs .
Through afforestation , reforestation and cutting down agricultural emissions , by one estimate , carbon dioxide equivalent to 40 parts per million could be extracted from the atmosphere by 2050 .