Are forest seed sources being used for ecological restoration in dry tropical forests across three South American countries?

Deforestation in tropical dry forest ecosystems is one of the primary causes of a reduction in biodiversity for flora and fauna worldwide. In response, ecological restoration has become a strategy to recover and reverse such degradation. These activities are part of the goals of the United Nations’ Sustainable Development Goals and Decade on Ecosystem Restoration (2021–2030). Restoration begins with characterising phenotypic diversity, which provides the basis for selecting tree individuals with desirable traits to serve as seed sources in natural forests. These sources would further feature high adaptability and productivity – factors that enhance seed propagation in nurseries, enabling their subsequent multiplication and implementation in specific areas for restoration processes. The objective of this research was to conduct a systematic review to characterise the current landscape of ecological restoration in tropical dry forests across key South American regions, including the Cerrado and Caatinga in Brazil, the Gran Chaco in Argentina, and the tropical dry forest of the department of Huila in Colombia. The importance of seed sources in restoration programmes was described, and the advances in the implementation of forest species as seed sources were highlighted. To do this, a systematic review was conducted using data from Web of Science, Scopus, and SciELO, with statistical analysis performed in the software R. The results identified 671 articles, and of these, 60 articles were considered to meet the appropriate criteria for carrying out the study. Finally, the seed sources used in restoration processes in hotspots such as the Cerrado, Caatinga, the Gran Chaco, and the tropical dry forest of the Huila region have had a great impact on the recovery of tropical dry forest through assisted restoration, where the availability of high-quality seed and plant material is ensured.