system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a particular type of tree that can naturally convert co2 more efficiently than other trees?

which can then be planted in condensed urban environments.
gpt
In general, broadleaf trees (as opposed to needleleaf trees) tend to have higher maximum photosynthetic capacities. If they are not resource limited, they can sequester more carbon. 

What is also important to consider is how long carbon will be sequestered from the atmosphere (carbon residence time). Needleleaf trees tend to decompose more slowly due to their nitrogen content and carbon stability in the tree tissues, making them less degradable. They also tend to be longer lived, but it really depends on the environment that the tree is in. The boreal forests (northern latitudes) are dominated by needleleaf trees because it is colder. Most of the carbon is stored in soils because there is less microbial decomposition. In the tropics, there is a lot more primary productivity (growth), and there are no needleleafs in the tropics, but it is warm and rapid nutrient cycling, so much less carbon stored in soils in most locations. There are exceptions... a peat bog was discovered in the Congo and it stores a lot of carbon.