Does Tree Species Composition Affect Productivity in a Tropical Planted Forest?

Abstract

AbstractWith growing pressure on primary forests from destructive land uses, increasing the diversity of native species plantations can increase ecosystem service provision, such as timber production or carbon sequestration, thus better supporting sustainable livelihoods. Understanding the effects of tree species composition on productivity can inform plantation design and ecological restoration strategies. However, tree species composition effects have been neglected in experimental biodiversity‐ecosystem function (BEF) research. This study uses a 10‐yr data set from one of the first tropical planted forest experiments established with native species and designed for BEF research at scales relevant to forest management. At our site in Sardinilla, Panama, we established plots containing 6 species from a pool of 18, in four combinations, to investigate how composition affects species and plot productivity. We used basal area as a proxy for productivity through time, measured annually, and summed this at species and plot levels for analysis. We found that plots that differed in species composition appeared to differ in temporal rate of basal area increase, but did not differ in BA after 10 yr. Species were generally consistent in size between compositions, and composition performance was correlated with the size of component species, suggesting that species identities were most important in determining plot productivity. Our results suggest that species choice can be based on preferences for individual species, as species performance was consistent across composition contexts. We make recommendations for the use of particularly productive species that also provide multiple services such as Guazuma ulmifolia, Spondias mombin, and Anacardium excelsum.