Heterogeneity of ecological patterns, processes, and funding of marine manipulative field experiments conducted in Southeastern Pacific coastal ecosystems

Ecological manipulative experiments conducted in marine coastal ecosystems havesubstantially improved ecological theory during the last decades and have provideduseful knowledge for the management and conservation of coastal ecosystems.Although different studies report global trends in ecological patterns worldwide,Southeastern Pacific coastal ecosystems have been poorly considered. Given thatthe SE Pacific coast encompasses diverse coastal ecosystems, consideration of studies conducted along this range can shed light on the heterogeneity of processes regulating coastal communities. We reviewed the biotic interactions and habitat typeconsidered, as well as the complexity in terms of spatial and temporal extent of manipulative field experimental studies conducted along the SE Pacific coast from 0°Sto 56°S (Ecuador to Chile). We test the effect of funding reported by different studiesas a main factor limiting experimental complexity. From field ecological studies published from 1970 to 2016, we found that 81 studies were truly manipulative, in whichone or multiple factors were "manipulated." Around 77% of these studies were located between 21°S and 40°S, and conducted in intertidal rocky habitats. An increase in experimental studies was observed between 2010 and 2015, especiallyfocused on herbivore-alga interactions, although we found that both the temporalextent and spatial extent of these studies have shown a decrease in recent decades.Funding grant amount reported had a positive effect on elapsed time of field experiments, but no effect was observed on spatial extent or in the biotic interactionsconsidered. Elapsed time of experiments was different among the main biotic interactions considered, that is, herbivory, predation, and competition. We suggest that tofurther progress in applied ecological knowledge, it will be necessary to considerpollution and urbanization processes explicitly using a field experimental framework.This information could improve our understanding of how ecosystems present alongthe SE Pacific coast respond to climate change and increased levels of humaninterventions.