Dykstra (2002) says tropical native forests yield only about 30 m3/ha of timber, that is, about 10 trees/ha of many different species. And in parts of Africa it could be only about a tree per 10 ha. Compare that to temperate conifer forests which yield 500 m3/ha, so the costs of tropical forest exploitation (roads, skids, mapping, cutting of vines) amount to about 50 times more than in temperate forests. The Reduced Impact Logging (RIL) seems an oxymoron in the case of tropical native forests. In trials at Kalimantan concessions of Alas Kusuma Group (Suparma et al 2002), they found that it will be viable only if the regulators make it mandatory for the whole country, at a premium price for such timber. Currently, they get the work done through quantity based incentives with little supervision. RIL requires a total revamping of the system. My suggestion is that we apply a moratorium on road building and commercial logging in tropical native forests (allow only community-based, controlled, non-timber forest product exploitation) until such time air lifting of tropical timber becomes economically viable.
Dykstra, Dennis P. 2002 Reduced impact logging: concepts and issues
Suparna, Nana et al 2002 Implementing reduced impact logging in the Alas Kusuma Group
– in Applying Reduced Impact Logging to Advance Sustainable Forest Management, Ed: Enters T. et al, RAP 14, FAO Regional Office for Asia and the Pacific, Thailand.
I do not know too much of the Technical aspects, but can state with confidence that Tropical Forests if Commercially exploited responsibly and sustainably, their ecological value can be preserved & sustained.
Any plant removal will decrease ecological value imo :)
That highly depends on the sustainability measures taken into consideration. e.g.
If the adaptability features such as fitness, vitality and regeneration capacity of given tree species are ensured within the forests, then its ecological value may be preserved/sustained.
Going commercial can mean trying to ensure profitability and in most cases maximization of profits!. I don't believe that one can go commercial and still be ready to compromise the profit aspect based on ecological restoration and conservation of tropical forests. So commercial harvesting will definitely compromise ecological conditions of the tropical forests as Dykstra reports. However, it also depend on the products that are harvested, leaving apart timber which is definitely destructive! Fruits, mushrooms, medicinal plants, edible insects and all other edible and inedible plants that can be of economic importance to the communities and the market at large. These will as well depend on the sustainable harvesting levels.
One way to manage tropical forests sustainably is by utilizing non-timber forest products such as honey bees, and environmental services, forest products such as timber need to be harvested sustainably and need to be developed on land owned by the community in the form of owned community forests