An Overview of Studies on Trophic Ecology in the Marine Environment: Achievements and Perspectives
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Neotropical Biology and Conservation 6(3):143-155, september-december 2011 © by Unisinos - 10.4013/nbc.2011.63.01 An overview of studies on trophic ecology in the marine environment: Achievements and perspectives Um panorama sobre os estudos de ecologia trófica em ambientes marinhos: Resultados e perspectivas Martin Lindsey Christoffersen1* [email protected] Abstract Classical approaches to trophic ecology of marine species has focused on trophic struc- Maria Elisabeth de Araújo2 ture, trophodynamics, dominant and keystone species, ecosystem maturity, energy [email protected] transfer, and anthropic effects. A recent breakthrough for evaluating the structure of com- munities has been the application of phylogenetic methods to community ecology. This Joaquim Olinto Branco3 recent approach is known as community phylogenetics. Although this perspective is still [email protected] not common in trophic studies, phylogenetic methods promise new insights into the old ecological question on how communities are assembled in time. Integrating phylogene- tics and ecosystem function creates the possibility of predicting ecological consequen- ces of biodiversity shifts in a changing world. Once we understand the structure and functioning of the ecosystem in a historical context, we should be able to avoid human or natural disturbances that draw a system away from its state of maximum complexity. Key words: trophic structure, trophodynamics, keystone species, ecosystem maturity, energy transfer, anthropic effects, community phylogenetics. Resumo Abordagens clássicas para estudos de ecologia trófica de species marinhas focam a es- trutura trófica, a trofodinâmica, espécies dominantes e espécies-chave, maturidade de ecossistemas, transferência de energia, e efeitos antrópicos. Um avanço recente para avaliar a estrutura de comunidades foi a aplicação de métodos filogenéticos à ecologia de comunidades. Esta abordagem recente é conhecida como filogenia de comunida- des. Embora esta perspectiva ainda não seja comum em estudos tróficos, métodos filogenéticos prometem novas abordagens à velha questão ecológica de como entender a organização de comunidades ao longo do tempo. A integração de filogenia com o funcionamneto de ecossistemas cria a possibilidade de prever as consequências de alterações na biodiversidade num mundo em mudança. Uma vez entendida a estrutura e o funcionamento do ecossitema num contexto histórico, deveremos poder evitar alte- 1 Universidade Federal da Paraíba, De- rações naturais ou humanas que tendem a desviar o sistema ecológico do seu estado partamento de Sistemática e Ecologia, Cidade Universitária, 58.059-900, João de complexidade máxima. Pessoa, PB, Brazil. 2 Universidade Federal de Pernambuco, Palavras-chave: estrutura trófica, trofodinâmica, espécies-chave, maturidade de ecossis- Departamento de Oceanografia, Av. temas, transferência de energia, efeitos antrópicos, filogenia de comunidades. Arquitetura, s/n, Cidade Universitária, 50.740-550, Recife, PE, Brazil. 3 Centro de Ciências Tecnológicas da Terra e do Mar, Universidade Vale do Itajaí (UNIVALI), Rua Uruguai, 458, Cx. P 360, CEP 88302-202, Itajaí, SC, Brazil. * Corresponding author Martin Lindsey Christoffersen, Maria Elisabeth de Araújo, Joaquim Olinto Branco Introduction trophic functions in coastal systems between basal and top species. Chains represent the best way the communi- involving more than six species are Most studies on marine macrobenthic ties can adapt to exploit the existing rare (Hutchinson, 1959; Pimm, 1982; communities have been conducted resources as a response to physical Cohen et al., 1986). The knowledge in north temperate regions. Tropical gradients (Carvalho et al., 2010). of diet is important for the establish- and subtropical macrobenthos is less Marine biodiversity is higher in ben- ment of its nutritional needs and of known, especially the South Atlantic thic rather than pelagic systems. The the interactions with other organisms fauna (Santos and Pires-Vanin, 2004). best way to conserve marine diversity (Albertoni et al., 2003). W. Odum and In relation to temperate regions, tropi- is to conserve habitat and landscape Heald (1975) used effective trophic cal systems are typically dominated diversity in the coastal area. Feeding level to group various taxa into com- by smaller species (Froese et al., 2004, relationships may cause invasions, mon feeding categories. The emphasis 2005). There is a reduced biomass in extirpations, and population fluctua- in all of these studies has been at the low latitudes, compared to middle tions of a species that dramatically ecosystem level (Christian and Lucz- and high latitudes (Chardy and Cla- affect other species within a variety kovich, 1999). vier, 1988). In the tropical zone this of natural habitats (Williams et al., The analysis of the trophic structure kind of study is more complex since 2002). Macrobenthic communities are of benthic communities is also a use- a large number of species are present now used worldwide as bioindicators ful way to determine the main energy and are frequently represented by only (Diaz and Rosenberg, 1995; Belan, flow at the ecosystem level. Most ec- a few individuals. The high biological 2003; Carvalho et al., 2006; Cardoso ological research has relied on trophic diversity obscures the recognition of et al., 2007). groups as a classification scheme for specific food webs responsible for Food webs, descriptions of who eats defining functional diversity (Micheli the larger part of the energy flow whom in ecosystems, provide com- and Halpern, 2005). Food web analy- (Paiva, 1993; Santos and Pires-Vanin, plex yet tractable depictions of bio- sis has also been a well-documented 2004). Trophic structure of tropical diversity, species interactions, and tool to achieve a fisheries ecosys- fish communities in particular con- ecosystem structure and function tem approach and to understand the trast with those from temperate re- (Dunne et al., 2002). Strong and ecosystem under various scenarios gions in terms of more efficient use of weak trophic links are responsible (Abarca-Arenas et al., 2007; Pauly et relatively low-quality food resources for ecological dynamics among di- al., 1998, 2000). (Harmelin-Vivien, 2002; Floeter et verse assemblages of species. The use Both abiotic (temperature, salinity, al., 2004; Ferreira et al., 2004). of trophic groups to characterize the substrate) and biotic factors (compe- Coastal ecosystems are relatively rich role of macrobenthos in marine com- tition, predation) play a role in shap- in nutrients and play a significant role munities is advantageous since it in- ing macrobenthic communities (An- in the development of many species corporates estimates of macrobenthic germeier and Winston, 1998). Food of economic interest. Studies on the community structure, and assesses or availability plays an important role feeding habits of macroinvertebrates infers community functioning (Gaston in the structure of coastal commu- and demersal fish, even those of a et al., 1995; Boaventura et al., 1999). nities in addition to abiotic factors descriptive character, provide basic On the other hand, feeding patterns of (Vaslet et al., 2010). Predation func- information for understanding the macrobenthic organisms have been tions in resource limitation (Verity, trophic relations of species (Rocha et frequently used to distinguish ecologi- 1998). Trophic interactions are one al., 2007; Gasalla and Soares, 2001). cal zones (Pearson and Rosenberg, of the determinants of distribution Coastal systems such as lagoons, sea 1987; Boaventura et al., 1999; Dias and abundance of organisms (Duarte grass banks and estuaries are char- et al., 2001). Knowledge of both web and Garcia 2004). Trophic ecology of acterized by high eco-physiological structure and interaction strengths is a macrobenthic communities in estuar- capacities of biological communities key to understanding how ecological ies may be used not only to infer com- against extremely varying environ- communities function (Berlow et al., munity function, but may also provide mental conditions, in space and time 2004). insights into community responses (Villanueva et al., 2006; Bascompte, The feeding roles of species are thus following disturbances (Gaston et 2009; Ings et al., 2009). The insta- important tools for the evaluation of al., 1998). Trophic structure has thus bility of the coastal zone affects the the structure and functioning of eco- become one of the primary ways by benthic community, determining the systems (Krebs, 1989). Species occur which ecologists organize communi- patterns of distribution and density at top, intermediate and basal trophic ties and ecosystems (Christian and and the trophic relationships among levels (Williams and Martinez, 2000). Luckzkovich, 1999). the species (Santos and Pires-Vanin, Food chains tend to be short, typi- In this paper we overview the accom- 2004). The existence of gradients of cally with only three or four kinds plishments of classical approaches to 144 Volume 6 number 3 september - december 2011 An overview of studies on trophic ecology in the marine environment: Achievements and perspectives the study of trophic structure in ma- Assigning of feeding types to each Luczkovich et al. (2003) defined rine environments, and then point out species is sometimes ambiguous and trophic role similarity as species that present developments and future di- not consensual (Chardy and Clavier, play the same structural roles, even rections in community phylogenetics.