High tree diversity enhances light interception in tropical forests

• Published in: The Journal of ecology 2021-07, Vol.109 (7), p.2597-2611
• Main Authors: Duarte, Marina Melo, Moral, Rafael de Andrade, Guillemot, Joannès, Zuim, Caroline Isaac Ferreira, Potvin, Catherine, Bonat, Wagner Hugo, Stape, José Luiz, Brancalion, Pedro H. S.
• Format: Article
• Language: English
• Subjects: Agricultural sciences; BEF theory; Biodiversity and Ecology; biodiversity and ecosystem functioning theory; Climate change; Climate change mitigation; complementarity; Dry season; ecological processes; ecosystem services; Environmental restoration; Environmental Sciences; Forests; Horizontal distribution; Interception; Life Sciences; Light; Light interception; light partitioning; Mitigation; Monoculture; Monoculture (aquaculture); Photosynthetically active radiation; Plant cover; Plant diversity; Primary production; Rainforests; restoration ecology; Silviculture, forestry; Species; Trees; Tropical climate; Tropical forests; Vertical distribution
• ISSN: 0022-0477; 1365-2745
• DOI: 10.1111/1365-2745.13669

Understanding the processes that underlie the effects of tree diversity on primary production is of foremost importance to enhance climate change mitigation by tropical forests. Here, we investigated the effects of tree diversity on light interception over space and time in two tropical tree experiments, located in Panama—Sardinilla site (monocultures to 18‐species mixtures), and in Brazil—Anhembi site (20‐ to 114‐species mixtures). We assessed intercepted photosynthetically active radiation (iPAR) over horizontal grids and vertical transects (up to 5 m high in Sardinilla and up to 4 m high in Anhembi), in plots containing different richness levels and combinations of species. Light interception increased from monocultures to 5‐species mixtures in Sardinilla and from 20‐ to 114‐species mixtures in Anhembi (during the dry season). At the Sardinilla site, five‐species mixtures showed iPAR comparable to the best performing monocultures, despite substantial differences observed among monocultures. Diversity‐iPAR relationships changed seasonally and were more pronounced during the dry season. Tree richness promoted a less variable temporal and spatial (i.e. both horizontal and vertical) distribution of light interception. Synthesis. High tree diversity (i.e. over a hundred species in mixture) maximizes the amount of light intercepted by the canopy in restored tropical forests through more even capture in space and time. Diversity‐light interception relationships should be critically considered for designing cost‐efficient large‐scale tropical forest restoration programs. Resumo Compreenderos processos que fundamentam os efeitos da diversidade arbórea sobre a produçãoprimária é fundamental para maximizar o papel de florestas tropicais namitigação de mudanças climáticas. Neste trabalho, investigamos os efeitos dadiversidade de árvores sobre a interceptação de luz ao longo do tempo e doespaço, em dois experimentos de florestas tropicais, localizados no Panamá –área Sardinilla (contendomonoculturas a misturas de 18 espécies) e no Brasil – área Anhembi (com misturas de 20 a 114 espécies). Avaliamosa radiação fotossinteticamente ativa interceptada (iPAR) ao longo do espaçohorizontal e de transectos verticais (de até 5 m de altura em Sardinilla e de até 4 m de altura em Anhembi), em parcelas contando comdiferentes níveis de riqueza e combinações de espécies. Ainterceptação de luz aumentou de monoculturas a misturas de cinco espécies em Sardinilla e entre misturas de 2