δ13C and δ15N comparisons among different co-occurring lichen species from littoral rocky substrata

2005 ◽  
Vol 37 (1) ◽  
pp. 93-95 ◽  
Author(s):  
Pascal Riera
Keyword(s):  
Stable Isotopes ◽  
Vascular Plants ◽  
Trophic Structure ◽  
Ecological Approach ◽  
Vertical Zonation ◽  
Δ13c And Δ15n ◽  
Biological Communities ◽  
Carbon And Nitrogen ◽  
Baseline Information ◽  
Rocky Habitats

The distributions of natural stable isotopes of carbon and nitrogen have been extensively investigated in a variety of primary producers such as vascular plants and algae to provide baseline information of the trophic structure of various ecosystems (Currin et al. 1995). However, there have been few attempts to use this ecological approach to characterize lichens which frequently constitute the principal vegetation in many rocky habitats (Gilbert 2000). Rocky sea shores are characterized by a vertical zonation of biological communities which fall into three major zones: supralittoral, mediolittoral and infralittoral. The supralittoral zone is rarely submerged and is typically covered by a vegetation of lichens and cyanobacteria (Lewis 1964; Russel 1991).

Stable isotopes reveal post-release trophodynamic and ontogenetic changes in a released finfish, mulloway (Argyrosomus japonicus)

2010 ◽  
Vol 61 (3) ◽  
pp. 302 ◽  
Author(s):  
Matthew D. Taylor ◽  
Debashish Mazumder
Keyword(s):  
Stable Isotopes ◽  
Isotopic Composition ◽  
Turnover Rate ◽  
Isotope Composition ◽  
Wild Fish ◽  
Ontogenetic Changes ◽  
Nitrogen Stable Isotope ◽  
Δ13c And Δ15n ◽  
Carbon And Nitrogen ◽  
Nitrogen Isotopic Composition

Carbon and nitrogen stable isotope ratios were analysed for hatchery-reared, recaptured and wild mulloway, Argyrosomus japonicus, to investigate temporal and growth-related changes in isotopic composition for stocked fish after release, and to evaluate changes in isotopic composition in terms of ontogenetic dietary switches. δ13C and δ15N values decreased and increased, respectively, after release. The isotope composition of released fish was distinct from wild fish until 200 days after release, but after 200 days post-release fish did not differ significantly from wild fish of similar or greater sizes. Abrupt dietary transitions from crustaceans to teleost fish (>50 cm total length (TL)) were evident in a rapid δ13C and δ15N change in wild mulloway, and δ15N was significantly greater in wild fish >65 cm TL compared with wild fish <50 cm TL. Multivariate carbon and nitrogen isotopic data were suitable for separating stocked and wild fish for up to 200 days after release, but did not separate wild fish grouped according to dietary composition. Carbon and nitrogen isotopic composition closely reflected dietary transitions and rapid adaptation by stocked mulloway to wild diets, which was evident in a high tissue turnover rate of up to 0.017 day–1. Stable isotopes are a useful tool for examining the integration of released fish into stocked ecosystems and can be used to describe convergence in the diets of wild and released fish.

Trophic structure of mesopelagic fishes in the western Mediterranean based on stable isotopes of carbon and nitrogen

2014 ◽  
Vol 138 ◽  
pp. 160-170 ◽  
Author(s):  
M. Valls ◽  
M.P. Olivar ◽  
M.L. Fernández de Puelles ◽  
B. Molí ◽  
A. Bernal ◽  
...  
Keyword(s):  
Stable Isotopes ◽  
Trophic Structure ◽  
Western Mediterranean ◽  
Carbon And Nitrogen

scholarly journals Trophic Structure of Neuston Across Tropical and Subtropical Oceanic Provinces Assessed With Stable Isotopes

2021 ◽  
Vol 7 ◽  
Author(s):  
Rui Albuquerque ◽  
Antonio Bode ◽  
Juan Ignacio González-Gordillo ◽  
Carlos M. Duarte ◽  
Henrique Queiroga
Keyword(s):  
Stable Isotopes ◽  
Trophic Structure ◽  
Nitrogen Isotopes ◽  
Stable Carbon ◽  
Carbon And Nitrogen ◽  
Wide Range ◽  
Deep Layers ◽  
Diffusive Fluxes ◽  
Trophic Niches ◽  
Degree Of Overlap

The marine neuston, organisms living in the vicinity of the ocean surface, is one of the least studied zooplankton groups. Neuston occupies a restricted ecological niche and is affected by a wide range of endogenous and exogenous processes while also being a food source to zooplankton fish migrating from the deep layers and seabirds. In this study, the neustonic communities were characterized along the Malaspina global expedition sampling tropical and subtropical oceanic provinces using stable carbon and nitrogen isotopes to explore their trophic structure and relationships with environmental variables. The differences in stable isotopes mirrored the patterns in environmental characteristics of each province. High δ13C values were associated with atmospheric carbon inputs, while the presence of dinoflagellates, coccolithophorids, and upwelling influence is related to low δ13C values. Similarly, provinces presenting high δ15N values were associated with denitrification and nitrate diffusive fluxes, whereas the presence of low δ15N is attributable to nitrogen supplied through N2 fixation by diazotrophs. Neuston showed a large overlap among the isotopic niches of four functional groups, with chaetognaths and detritivores generally exhibiting a smaller degree of overlap compared to carnivores and omnivores/herbivores. These results support the hypothesis of a common trophic structure in the neuston community across the ocean. However, the size of the niche, small in coastal areas and those influenced by upwelling and large in oligotrophic regions, and their overlap, low in more productive provinces and high in oligotrophic provinces, may be associated with food availability. Small trophic niches are associated with a dominance of specialized over-opportunistic feeding in productive environments.

Trophic structure and energy flow in backwater lakes of two large floodplain rivers assessed using stable isotopes

2004 ◽  
Vol 61 (1) ◽  
pp. 12-22 ◽  
Author(s):  
Brian R Herwig ◽  
Daniel A Soluk ◽  
John M Dettmers ◽  
David H Wahl
Keyword(s):  
Stable Isotopes ◽  
Energy Flow ◽  
Aquatic Invertebrates ◽  
Trophic Structure ◽  
Larval Fish ◽  
Carbon And Nitrogen ◽  
Trophic Enrichment ◽  
Isotope Studies ◽  
Floodplain Rivers ◽  
Terrestrial Material

Carbon and nitrogen stable isotopes (δ13C and δ15N, respectively) were measured for locally abundant primary producers, detritus, aquatic invertebrates, and fish in backwater lakes of two large floodplain rivers in an effort to understand patterns of energy dependence and trophic structure within these habitats. We observed trophic enrichment values for 15N that were within the ranges observed for other aquatic systems but were often considerably lower than the 3.4‰ typically assumed in stable isotope studies. Production based on benthic and terrestrial material, combined with planktonic production for larval fish, appears to be an important energy source supporting consumers in backwater lakes of large floodplain rivers. Our isotopic data challenge the conventional wisdom that macrophytes are centrally involved in supplying carbon to aquatic consumers in shallow lakes and that food webs in most lakes are sustained almost exclusively by carbon fixed by phytoplankton.

Disentangling the role of shared ancestry and the environment on leaf stable isotopes

2019 ◽  
Author(s):  
Marko J. Spasojevic ◽  
Sören Weber1
Keyword(s):  
Stable Isotopes ◽  
Environmental Conditions ◽  
Evolutionary History ◽  
Environmental Control ◽  
Phylogenetic Signal ◽  
Individual Species ◽  
Habitat Types ◽  
Δ13c And Δ15n ◽  
Environmental Controls ◽  
Shared Ancestry

Stable carbon (C) and nitrogen (N) isotopes in plants are important indicators of plant water use efficiency and N acquisition strategies. While often regarded as being under environmental control, there is growing evidence that evolutionary history may also shape variation in stable isotope ratios (δ13C and δ15N) among plant species. Here we examined patterns of foliar δ13C and δ15N in alpine tundra for 59 species in 20 plant families. To assess the importance of environmental controls and evolutionary history, we examined if average δ13C and δ15N predictably differed among habitat types, if individual species exhibited intraspecific trait variation (ITV) in δ13C and δ15N, and if there were a significant phylogenetic signal in δ13C and δ15N. We found that variation among habitat types in both δ13C and δ15N mirrored well-known patterns of water and nitrogen limitation. Conversely, we also found that 40% of species exhibited no ITV in δ13C and 35% of species exhibited no ITV in δ15N, suggesting that some species are under stronger evolutionary control. However, we only found a modest signal of phylogenetic conservatism in δ13C and no phylogenetic signal in δ15N suggesting that shared ancestry is a weaker driver of tundra wide variation in stable isotopes. Together, our results suggest that both evolutionary history and local environmental conditions play a role in determining variation in δ13C and δ15N and that considering both factors can help with interpreting isotope patterns in nature and with predicting which species may be able to respond to rapidly changing environmental conditions.

Sign in / Sign up

Export Citation Format

Share Document