Match the following descriptions with the associated silvicultural concept: 1: Removal of trees in blocks of less than 1 ha. 2: Stand harvesting is done in several successive cuttings that protect the regeneration of an even-aged stand. 3: Frequent but low intensity cuttings to harvest mature trees and regenerate the stand while maintaining an uneven-aged structure. 4: Clearcutting and subsequent vegetative regeneration for some hardwoods. 5: A one time harvesting followed by the regeneration of the stand, producing an even-aged stand. 6: Removal of trees with the main objective of promoting growth of remaining standing trees.匹配题