Intensive silvicultural practices drive the forest restoration in southern Brazil

Abstract

The restoration of degraded environments is a challenging process due to the presence of adverse factors, which can prevent the establishment and development of forest species. The use of appropriate methods and species, which are able to adapt to the soil and climatic conditions, enable successful conservation plantings. Herein, we aim to identify the performance of native forest species grown under two planting models and different silvicultural practices in a degraded riparian area in the extreme south of the Atlantic Forest Biome. The experiment was initiated in September 2015 with a randomized block design arranged in a 3 × 2 factorial scheme (three silvicultural practices and two planting models). We evaluated the performance of nine native species by the analysis of morphological (i.e., survival, height, and stem diameter) and physiological attributes (i.e., photosynthetic pigments and chlorophyll a fluorescence). The use of intensive silvicultural practices in restoration plantations maximized tree survival rates, height, and stem growth, and provided better values for the physiological attributes. The two planting models tested in this study (i.e., “framework species” and diversity) can be used in future restoration projects in subtropical regions associated with intensive silvicultural practices. Solanum mauritianum, among other studied species, presented excellent rates of survival and growth. Several secondary species (e.g., Actinostemon concolor, Trichilia elegans, and Eugenia rostrifolia) propagated from the seedling transplants, also showed the potential to enrich forest plantations in degraded environments.