Photosynthetically Active Radiation Analysis in Forest Management Areas before and after the Second Cycle of Timber Harvest in Itacoatiara, AM

• Grant number: 25/01644-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2025
• End date: March 31, 2026
• Field of knowledge: Agronomical Sciences - Forestry Resources and Forestry Engineering - Forest Management
• Principal Investigator: Edson José Vidal da Silva
• Grantee: Laura Aluotto de Oliveira
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Solar radiation is the Earth's main energy source, it is fundamental for the functioning of different physical, chemical and biological processes, especially in forest ecosystems. For photosynthesis to happen, only a fraction of solar radiation, called Photosynthetically Active Radiation (PAR), is utilized, covering wavelengths between 0.4 and 0.7 ¿m. Thus, a landscape radiation use efficiency can be assessed by the amount of PAR absorbed by the canopy. Forest management can change the fraction of active radiation that enters the forest due to the creation of clearings because of operations like roads opening. In such a context, the increased PAR incidence can favour the regeneration of species that require more light and affect the biomass accumulation and the seedling mortality. However, the reduced impact logging seeks to minimize the damages to the remaining vegetation, reducing clearings, in order to promote the sustainability of the activity in the long-term. Therefore, this study proposes the quantification of the Photosynthetically Active Radiation incident light and intercepted by the canopy using ceptometers in different Reduced Impact Logging (RIL) managed areas in the Amazon, as well as correlating such data with the management infrastructure data so as to understand how these activities impact the incident light inside the forest.