Fatty acids (FA) are inextricably linked with key physiological and biochemical processes thus integral to proper ecosystem functioning. FA not biosynthesized effectively by animals termed essential fatty (EFA). These EFA important "drivers" of health/stability therefore highly conserved in aquatic food chains. Aquatic organisms have been continue be our primary source readily available EFA. However, overfishing burgeoning population may acting concert threaten access this Here, we review...

Phytoplankton are the main source of energy and omega-3 (n-3) long-chain essential fatty acids (EFA) in aquatic ecosystems. Their growth biochemical composition affected by surrounding environmental conditions, including temperature, which continues to increase as a result climate warming. Increasing water temperatures may negatively impact production EFA phytoplankton through process homeoviscous adaptation. To investigate this, we conducted an exploratory data synthesis with 952 acid (FA)...

Long-chain polyunsaturated fatty acids (LC-PUFA) are critical for the health of aquatic and terrestrial organisms; therefore, understanding production, distribution, abundance these compounds is imperative. Although dynamics LC-PUFA production distribution in environments has been well documented, a systematic comprehensive comparison to not rigorously investigated. Here we use data synthesis approach compare contrast acid profiles 369 organisms. Habitat trophic level were interacting...

We measured concentrations of essential fatty acids (EFAs) in four size categories planktonic organisms— seston (10–64 µm), microzooplankton (100–200 mesozooplankton (200–500 and macrozooplankton (≫500 230m)—and rainbow trout ( Oncorhynchus mykiss ) coastal lakes. Size‐dependent patterns specific (FAs) are important for ecosystem function, because planktivorous fish some invertebrates size‐selective predators. demonstrate that the retention individual FAs differs among organisms our study...

Rapid climate changes are occurring in the Arctic, with substantial repercussions for arctic ecosystems. It is challenging to assess ecosystem remote polar environments, but one successful approach has entailed monitoring diets of upper trophic level consumers. Quantitative fatty acid signature analysis (QFASA) and carbon isotope (δ(13) C-FA) patterns were used East Greenland (EG) bears (Ursus maritimus) (n = 310) over past three decades. QFASA-generated diet estimates indicated that, on...

Docosahexaenoic acid (DHA) is an essential, omega-3, long-chain polyunsaturated fatty that a key component of cell membranes and plays vital role in vertebrate brain function. The capacity to synthesize DHA limited mammals, despite its critical neurological development health. For humans, most commonly obtained by eating fish. Global warming predicted reduce the de novo synthesis algae, at base aquatic food chains, which expected transferred We estimated global quantity (total per capita)...

Aquatic ecosystems are fuelled by biogeochemical inputs from surrounding lands and within-lake primary production. Disturbances that change these may affect how aquatic function deliver services vital to humans. Here we test, using a forest cover gradient across eight separate catchments, whether disturbances remove terrestrial biomass lower organic matter into freshwater lakes, thereby reducing food web productivity. We focus on deltas formed at the stream-lake interface where...

Polyunsaturated fatty acids (PUFA), especially long-chain (i.e., ≥20 carbons) polyunsaturated (LC-PUFA), are fundamental to the health and survival of marine terrestrial organisms. Therefore, it is imperative that we gain a better understanding their origin, abundance, transfer between within these ecosystems. We evaluated natural variation in PUFA distribution abundance exists ecosystems by amassing analyzing, using multivariate analysis variance (ANOVA) methods, >3000 acid (FA) profiles...

We used a scanning spectroradiometer to conduct underwater optical surveys of 44 waterbodies during the ice‐free seasons three consecutive years in wetlands and lakes central Saskatchewan, Canada. The ranged widely dissolved organic carbon (DOC) concentration (4.1–156.2 mg L −1 ) conductivity (270–74,300 mohms cm ). Although penetration UV radiation (UV‐R; 280–400 nm) these systems was largely function DOC concentration, as has been reported previously, UV‐R penetrated more deeply saline...

Abstract Poikilothermic organisms accumulate highly unsturated FA (HUFA) in their lipids at reduced temperatures to maintain cell membrane fluidity. In this study we investigated the effect of temperature on temporal trajectories fasting Daphnia pulex cultured a HUFA‐free diet. populations were maintained for 1 mon 22 and 11°C fed chlorophyte Ankistrodesmus falcatus . We observed conversion C 18 precursors EPA (20∶5n3) arachidonic acid (ARA; 20∶4n6) D. showed that long‐term exposure cold...

Numerous researchers have attempted to find suitable proxies for the lipid content of fishes. Owing high carbon lipids, C:N ratios been used as a predictor both purposes quantifying condition and stable isotope analyses. Here we examine utility predicting within among populations, validate commonly published percent – ratio models. No common model was found apply; instead, population-specific influences on were observed. Published prediction models significantly underestimated content, often...

Ecosystem change often affects the structure of aquatic communities thereby regulating how much and by what pathways energy critical nutrients flow through food webs. The availability essential to top predators such as seabirds that rely on resources near water's surface will be affected changes in pelagic prey abundance. Here, we present results from analysis a 25-year data set documenting dietary predatory seabird Laurentian Great Lakes. We reveal significant declines trophic position...

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsTheme Sections 482:17-28 (2013) - DOI: https://doi.org/10.3354/meps10278 Food web structure of a coastal Arctic marine ecosystem and implications for stability Bailey C. McMeans1,*, Neil Rooney2, Michael T. Arts3, Aaron Fisk1 1Great Lakes Institute Environmental Research, University Windsor, 401 Sunset Ave., Ontario N9B...

Calcium (Ca) concentrations are decreasing in softwater lakes across eastern North America and western Europe. Using long-term contemporary palaeo-environmental field data, we show that this is precipitating a dramatic change Canadian lakes: the replacement of previously dominant pelagic herbivores (Ca-rich Daphnia species) by Holopedium glacialis, jelly-clad, Ca-poor competitor. In some lakes, transformation being facilitated increases macro-invertebrate predation, both from native...

The biosynthesis of nutritionally important polyunsaturated fatty acids (PUFAs) in phytoplankton is influenced by environmental temperature. We investigated the potential climate warming to alter lipid dynamics Scenedesmus obliquus (Turpin) Kütz. comparing and acid (FA) profiles as well FA metabolism (using [1-14C] acetate) at 20°C 28°C. documented an overall decline (53%–37%) proportion n-3 PUFA (in particular, α-linolenic [ALA; 18:3n-3]), a concomitant increase saturated (SAFAs) total...

We tested the influence of two light intensities [40 and 300 μmol PAR / (m(2)s)] on fatty acid composition three distinct lipid classes in four freshwater phytoplankton species. chose species different taxonomic order to detect potentially similar reaction characteristics that might also be present natural communities. From samples bacillariophyte Asterionella formosa, chrysophyte Chromulina sp., cryptophyte Cryptomonas ovata zygnematophyte Cosmarium botrytis we first separated glycolipids...

Summary 1. Declining abundances of forage fish and the introduction establishment non‐indigenous species have potential to substantially alter resource habitat exploitation by top predators in large lakes. 2. We measured stable isotopes carbon (δ 13 C) nitrogen 15 N) field‐collected archived samples Lake Ontario lake trout ( Salvelinus namaycush ) five prey compared current trophic relationships this predator with historical samples. 3. Relationships between δ N age were temporally...

We tested, in the laboratory, influence of light intensity, temperature, and phosphorus (P) supply on fatty acid (FA) concentrations four freshwater algae: green algae Scenedesmus quadricauda (Turpin) Bréb. Chlamydomonas globosa J. Snow, cryptophyte Cryptomonas ovata Ehrenb., diatom Cyclotella meneghiniana Kütz. investigated main interactive effects two variables algal FA (i.e., intensity P or temperature supply). Interactive were most pronounced C. meneghiniana, but also found S. ovata....