Long-term Entomological Research on Canopy Arthropods in a Tropical Rainforest in Puerto Rico

TitleLong-term Entomological Research on Canopy Arthropods in a Tropical Rainforest in Puerto Rico
Publication TypeJournal Article
Year of Publication2017
AuthorsSchowalter, TD
JournalAmerican Entomologist
Date Published09/2017
Accession NumberLUQ.1325
Keywordsarthropods response to disturbance, canopy arthropods, disturbance, effects on ecosystem processes, environmental changes, Luquillo experimental forest
AbstractLong-term research is critical to addressing effects of environmental changes, especially climate or land use, on ecosystems and their constituent species, because short-term studies yield incomplete or even misleading impressions (Adams 2001). For example, long-term studies have revealed that community and ecosystem responses to a disturbance event reflect the legacy of disturbances and other environmental changes over periods of decades to centuries (Harding et al. 1998, Summerville et al. 2009, Schowalter et al. 2017). In other words, community structure at a point in time depends on the history of environmental changes that filter community composition in different ways; i.e., species survival and response after successive events depends on their respective tolerances to each event. Short-term studies are incapable of revealing such legacy or contingency effects. Insects provide valuable systems with which to study long-term effects of environmental changes. Insects represent the bulk of diversity (60-90% of all species) in terrestrial and freshwater ecosystems, have biomass often equal to or greater than that of more conspicuous vertebrates, and are highly responsive to changes in abiotic or host conditions (Schowalter 2016). Both above-and-below-ground arthropods have considerable capacity toalter rates and patterns of primary production, decomposition, soil properties, and biogeochemical fluxes (Mattson and Addy 1975, Belovsky and Slade 2000, Schowalter et al. 2011). Outbreaks of herbivorous species are among the most dramatic biological processes, often triggered by disturbances (Mattson and Haack 1987, Schowalter 2012). Outbreaks are capable of altering ecosystem conditions and climate in ways that may contribute to ecosystem resilience (Chapman et al. 2003, Classen et al. 2005, Fonte and Schowalter 2005, Frost and Hunter 2007, Schowalter et al. 2011, Schowalter 2016), as well as the delivery of ecosystem services (Schowalter 2013, 2016). Unfortunately, insects have received relatively little attention in long-term ecosystem studies. Entomologists traditionally have focused on the population dynamics of individual species and their associated hosts and natural enemies, whereas ecosystem ecologists tend to ignore insects or treat them as a single biotic pool (Hunter 2001). Clearly, entomologists could contribute greatly to longterm studies of ecosystem responses to environmental changes. Research sites in the U.S. Long Term Ecological Research (LTER) Network, and collaborating networks in entomologists in such studies is critical to understanding how environmental changes affect ecosystem structure, processes, and services.