Which biodiversity restoration method should the biologist use

They should choose reforestation method for restoration of biodiversity.

Explanation:

Biodiversity restoration is a practice that allows the preservation of an ecosystem in a region. It involves the method of renewing, restoring the habitat of species which is degraded, damaged, or destroyed either by the human intervention or by a natural hazard.

According to the given situation, the canopy thickness of the area can be recreated by reforestation. Reforestation is the process of replanting an area with trees. This means it is a process that involves the natural or intentional re-plantation of land, which was previously occupied by the forest or some amount of vegetation. Although, it will take some years but can provide habitat to wildlife and will prevent drastic climatic changes.