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Pörtner H O - - 2010
Ongoing climate change is predicted to affect individual organisms during all life stages, thereby affecting populations of a species, communities and the functioning of ecosystems. These effects of climate change can be direct, through changing water temperatures and associated phenologies, the lengths and frequency of hypoxia events, through ongoing ocean ...
Roth B M - - 2010
A process-based simulation model was used to examine the nature and intensity of food-web interactions that allow Osmerus mordax to dominate invaded lakes. The model simulates food-web interactions among linked populations of O. mordax, Coregonus artedi and Sander vitreus. Simulations indicated that O. mordax dominate where: (1) adult O. mordax ...
Haukås Marianne - - 2010
The present study reports diastereomer-specific accumulation of HBCD from a point source in five marine species representing a typical food web in a Norwegian coastal area. Samples of mussels, polychaetes, crabs and seabird eggs were analyzed for the diastereomers α-, β- and γ-HBCD, as well as lipid content and stable ...
Matich Philip - - 2011
1. Apex predators are often assumed to be dietary generalists and, by feeding on prey from multiple basal nutrient sources, serve to couple discrete food webs. But there is increasing evidence that individual level dietary specialization may be common in many species, and this has not been investigated for many marine ...
Liu Wei-chung - - 2010
Due to the structural complexity of nature, it is not always easy to identify topologically importance species in an ecosystem. In the past decade, several studies in ecology have developed methods for measuring species importance basing on direct and indirect inter-specific interactions. Here, by extending a previously developed methodology, we ...
Tack Ayco J M - - 2011
1. Shared enemies may link the dynamics of their prey. Recently, quantitative food webs have been used to infer that herbivorous insect species attacked by the same major parasitoid species will affect each other negatively through apparent competition. Nonetheless, theoretical work predicts several alternative outcomes, including positive effects. 2. In this paper, ...
Suzuki Kenta - - 2010
Population dynamics can reflect the body mass distribution of species because there is an allometric relationship between the average body mass of species and its metabolic timescale. Since predators are generally larger than their prey, a hierarchical structure from fast timescales to slow timescales can be a general structure in ...
Rohr Rudolf Philippe - - 2010
Several stochastic models have tried to capture the architecture of food webs. This approach is interesting, but it is limited by the fact that different assumptions can yield similar results. To overcome this limitation, we develop a purely statistical approach. Body size in terms of an optimal ratio between prey ...
Fauchald Per - - 2010
Removal of large predatory fishes from marine ecosystems has resulted in persistent ecosystem shifts, with collapsed predator populations and super-abundant prey populations. One explanation for these shifts is reversals of predator-prey roles that generate internal feedbacks in the ecosystems. Pelagic forage fish are often predators and competitors to the young ...
Wilson Erin E - - 2010
The difficulty of directly observing predatory events hinders a complete understanding of how predation structures food webs. Indirect approaches such as PCR-based and isotopic analyses clarify patterns of resource consumption but fail to distinguish predation from scavenging. Given that facultative scavenging is a ubiquitous and phylogenetically widespread foraging strategy, an ...
Shakya Sulochana - - 2010
Action thresholds are traditionally based on the density of pests and the economic damage they cause to crops. Pest damage assessments are usually made in a "sterile" environment, devoid of extenuating factors such as predators, parasitoids, and alternative food sources. Recently, the effects of a predator or parasitoid species have ...
Pangallo Kristin C - - 2010
Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are putative marine natural products that accumulate in marine mammal blubber in similar concentrations and patterns to biomagnifying organic pollutants. Here we measure concentrations of MBPs and 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) in 40 samples composed of eight fish species, two squid species, and six species of marine mammals. To ...
Kirmani Sahar N - - 2010
Foraging herbivores must satisfy their nutrient requirements in a world of toxic plants while also avoiding predators. Plant toxins and perceived predation risk at food patches should both reduce patch residency time, but the relative strengths of these factors on feeding decisions has rarely been quantified. Using an arboreal generalist ...
Utne-Palm Anne C - - 2010
Since the collapse of the pelagic fisheries off southwest Africa in the late 1960s, jellyfish biomass has increased and the structure of the Benguelan fish community has shifted, making the bearded goby (Sufflogobius bibarbatus) the new predominant prey species. Despite increased predation pressure and a harsh environment, the gobies are ...
Seymour Justin R - - 2010
Phytoplankton-produced dimethylsulfoniopropionate (DMSP) provides underwater and atmospheric foraging cues for several species of marine invertebrates, fish, birds, and mammals. However, its role in the chemical ecology of marine planktonic microbes is largely unknown, and there is evidence for contradictory functions. By using microfluidics and image analysis of swimming behavior, we ...
Wu Jiang-Ping - - 2010
Several currently used non-polybrominated diphenyl ether (PBDE) brominated flame retardants (BFRs), including hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB), and pentabromotoluene (PBT), are examined in the components of a freshwater food web from an electronic waste recycling site, South China. All these BFRs are detectable in ...
Petchey Owen L - - 2010
Few models concern how environmental variables such as temperature affect community structure. Here, we develop a model of how temperature affects food web connectance, a powerful driver of population dynamics and community structure. We use the Arrhenius equation to add temperature dependence of foraging traits to an existing model of ...
Woodward Guy - - 2010
Fresh waters are particularly vulnerable to climate change because (i) many species within these fragmented habitats have limited abilities to disperse as the environment changes; (ii) water temperature and availability are climate-dependent; and (iii) many systems are already exposed to numerous anthropogenic stressors. Most climate change studies to date have ...
Sarmento Hugo - - 2010
Previsions of a warmer ocean as a consequence of climatic change point to a 2-6 degrees C temperature rise during this century in surface oceanic waters. Heterotrophic bacteria occupy the central position of the marine microbial food web, and their metabolic activity and interactions with other compartments within the web ...
Bengtson Nash Susan - - 2010
In order to investigate the extent to which Perfluorinated Contaminants (PFCs) have permeated the Southern Ocean food web to date, a range of Antarctic, sub-Antarctic and Antarctic-migratory biota were analysed for key ionic PFCs. Based upon the geographical distribution pattern and ecology of biota with detectable vs. non-detectable PFC burdens, ...
Romero Gustavo Q - - 2010
1. Ecosystems may affect each other through trophic interactions that cross ecosystem boundaries as well as via the transfer of subsidies, but these effects can vary depending on the identity of species involved in the interaction. 2. In this study, we manipulated two terrestrial bromeliad-living spider species (Aglaoctenus castaneus, Corinna ...
Schofield Oscar - - 2010
Climate change will alter marine ecosystems; however, the complexity of the food webs, combined with chronic undersampling, constrains efforts to predict their future and to optimally manage and protect marine resources. Sustained observations at the West Antarctic Peninsula show that in this region, rapid environmental change has coincided with shifts ...
Hoegh-Guldberg Ove - - 2010
Marine ecosystems are centrally important to the biology of the planet, yet a comprehensive understanding of how anthropogenic climate change is affecting them has been poorly developed. Recent studies indicate that rapidly rising greenhouse gas concentrations are driving ocean systems toward conditions not seen for millions of years, with an ...
Borgå Katrine - - 2010
Climate change is expected to alter environmental distribution of contaminants and their bioaccumulation due to changes in transport, partitioning, carbon pathways, and bioaccumulation process rates. Magnitude and direction of these changes and resulting overall bioaccumulation in food webs is currently not known. The present study investigates and quantifies the effect ...
Tirok Katrin - - 2010
The individual functional traits of different species play a key role for ecosystem function in aquatic and terrestrial systems. We modeled a multispecies predator-prey system with functionally different predator and prey species based on observations of the community dynamics of ciliates and their algal prey in Lake Constance. The model ...
Park Hong-Hyun - - 2010
Predation, development, and oviposition experiments were conducted to evaluate Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) as a potential biological control agent for tomato russet mite, Aculops lycopersici (Massee) (Acari: Eriophyidae), which can be a serious pest of greenhouse tomatoes. Results showed that A. swirskii attacked all developmental stages of A. lycopersici ...
Travers Marc - - 2010
Predator-induced changes in physiology and behaviour may negatively affect a prey's birth rate. Evidence of such indirect predator effects on prey demography remains scarce in birds and mammals despite invertebrate and aquatic studies that suggest ignoring such effects risks profoundly underestimating the total impact of predators. We report the first ...
Solić M - - 2010
Vranjic Basin, in the eastern part of KastelaBay (middle Adriatic Sea), received municipal wastewater until offshore submarine outfalls were finished in November 2004. To identify the responses of the microbial community to changes in the trophic status of the marine environment, two 4-year periods were compared: a eutrophic period (2001-2004) ...
Kratina Pavel - - 2010
1. Intraguild predation is widespread in nature despite its potentially destabilizing effect on food web dynamics. 2. Anti-predator inducible defences affect both birth and death rates of populations and have the potential to substantially modify food web dynamics and possibly increase persistence of intraguild prey. 3. In a chemostat experiment, ...
Staniczenko Phillip P A - - 2010
Food web structure plays an important role when determining robustness to cascading secondary extinctions. However, existing food web models do not take into account likely changes in trophic interactions ('rewiring') following species loss. We investigated structural dynamics in 12 empirically documented food webs by simulating primary species loss using three ...
McHugh Peter A - - 2010
The number of trophic transfers occurring between basal resources and top predators, food chain length (FCL), varies widely in the world's ecosystems for reasons that are poorly understood, particularly for stream ecosystems. Available evidence indicates that FCL is set by energetic constraints, environmental stochasticity, or ecosystem size effects, although no ...
Brockmark S - - 2010
Theory suggests that habitat structure and population density profoundly influence the phenotypic development of animals. Here, we predicted that reduced rearing density and increased structural complexity promote food search ability, anti-predator response and the ability to forage on novel prey, all behavioural skills important for surviving in the wild. Brown ...
Rossberg Axel G - - 2010
A question central to modelling and, ultimately, managing food webs concerns the dimensionality of trophic niche space, that is, the number of independent traits relevant for determining consumer-resource links. Food-web topologies can often be interpreted by assuming resource traits to be specified by points along a line and each consumer's ...
Jonasson Sara - - 2010
beta-methylamino-L-alanine (BMAA), a neurotoxic nonprotein amino acid produced by most cyanobacteria, has been proposed to be the causative agent of devastating neurodegenerative diseases on the island of Guam in the Pacific Ocean. Because cyanobacteria are widespread globally, we hypothesized that BMAA might occur and bioaccumulate in other ecosystems. Here we ...
Culp Jennifer - - 2010
To assess the content of food industry Web sites targeting children by describing strategies used to prolong their visits and foster brand loyalty; and to document health-promoting messages on these Web sites. A content analysis was conducted of Web sites advertised on 2 children's networks, Cartoon Network and Nickelodeon. A ...
Smallegange Isabel M - - 2010
1. Ideal-free distribution theory assumes that in a patchy environment foragers maximize fitness and hence their feeding rate by balancing gains from more food against losses from more competition. Ultimately, individuals cannot increase their feeding rate by moving to another patch and they distribute themselves over patches in proportion to ...
Morozov Andrew Yu - - 2010
Food-web population models are rather sensitive to parameterization of functional response in predation terms. Theoretical studies predict enhancing of ecosystems' stability for a functional response of sigmoid type (Holling type III). The choice of a correct type of response is especially important for modelling outcome of grazing control of algal ...
Montagnes David J S - - 2010
Since the introduction of the microbial loop concept, awareness of the role played by protozooplankton in marine food webs has grown. By consuming bacteria, and then being consumed by metazooplankton, protozoa form a trophic link that channels dissolved organic material into the "classic" marine food chain. Beyond enhancing energy transfer ...
Sukhdeo Michael V K - - 2010
This review examines the historical origins of food web theory and explores the reasons why parasites have traditionally been left out of food web studies. Current paradigms may still be an impediment because, despite several attempts, it remains virtually impossible to retrofit parasites into food web theory in any satisfactory ...
Choh Yasuyuki - - 2010
Theory on intraguild (IG) predation predicts that coexistence of IG-predators and IG-prey is only possible for a limited set of parameter values, suggesting that IG-predation would not be common in nature. This is in conflict with the observation that IG-predation occurs in many natural systems. One possible explanation for this ...
von Berg Karsten - - 2010
Prey from the decomposer subsystem may help sustain predator populations in arable fields. Adding organic residues to agricultural systems may therefore enhance pest control. We investigated whether resource addition (maize mulch) strengthens aboveground trophic cascades in winter wheat fields. Evaluating the flux of the maize-borne carbon into the food web ...
Carrillo Daniel - - 2010
The red palm mite, Raoiella indica (Acari: Tenuipalpidae), is an important pest of palms (Arecaceae) and other species within the Zingiberaceae, Musaceae and Strelitziaceae families. Raoiella indica was discovered in the USA (Palm Beach and Broward counties, Florida) late in 2007, and it subsequently spread to other Florida counties. The ...
Zhang Jiang - - 2010
Food webs can be regarded as energy transporting networks in which the weight of each edge denotes the energy flux between two species. By investigating 21 empirical weighted food webs as energy flow networks, we found several ubiquitous scaling behaviors. Two random variables A(i) and C(i) defined for each vertex ...
Lindegren Martin - - 2010
Good decision making for fisheries and marine ecosystems requires a capacity to anticipate the consequences of management under different scenarios of climate change. The necessary ecological forecasting calls for ecosystem-based models capable of integrating multiple drivers across trophic levels and properly including uncertainty. The methodology presented here assesses the combined ...
Ianora Adrianna - - 2010
Traditionally, diatoms have been regarded as providing the bulk of the food that sustains the marine food chain and important fisheries. However, this view was challenged almost two decades ago on the basis of laboratory and field studies showing that when copepods, the principal predators of diatoms, feed on certain ...
Small Gaston E - - 2010
A central tenet of ecological stoichiometry is that consumer elemental composition is relatively independent of food resource nutrient content. Although the P content of some invertebrate consumer taxa can increase as a consequence of P-enriched food resources, little is known about how ecosystem nutrient loading can affect the elemental composition ...
Chase Jonathan M - - 2010
Habitat isolation is well known to alter patterns of species' abundance, richness, and the ratios of predators : prey. Less clear, however, is how isolation alters interactions within food webs. Here, we present the results from an experiment performed in artificial ponds (mesocosms) manipulating habitat isolation crossed with a predator ...
Johnson Pieter T J - - 2010
Recent efforts to include parasites in food webs have drawn attention to a previously ignored facet of foraging ecology: parasites commonly function as prey within ecosystems. Because of the high productivity of parasites, their unique nutritional composition and their pathogenicity in hosts, their consumption affects both food-web topology and disease ...
van der Hammen Tessa - - 2010
When intraguild predation is reciprocal, i.e. two predator species kill and feed on each other, theory predicts that well-mixed populations of the two species cannot coexist. At low levels of the shared resource, only the best competitor exists, whereas if the level of the common resource is high, the first ...
Lef?vre Emilie - - 2010
Recently, molecular environmental surveys of the eukaryotic microbial community in lakes have revealed a high diversity of sequences belonging to uncultured zoosporic fungi. Although they are known as saprobes and algal parasites in freshwater systems, zoosporic fungi have been neglected in microbial food web studies. Recently, it has been suggested ...
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