Search results for "ecological"
showing 10 items of 1263 documents
Do invasive alien plants really threaten river bank vegetation? : a case study based on plant communities typical for Chenopodium ficifolium : an ind…
2018
Riparian zones are very rich in species but subjected to strong anthropogenic changes and extremely prone to alien plant invasions, which are considered to be a serious threat to biodiversity. Our aim was to determine the spatial distribution of Chenopodium ficifolium, a species demonstrating strong confinement to large river valleys in Central Europe and an indicator of annual pioneer nitrophilous vegetation developing on river banks, which are considered to be of importance to the European Community. Additionally, the habitat preferences of the species were analysed. Differences in the richness and abundance of species diagnostic for riverside habitats, as well as the contribution of resi…
An Empirical Evaluation of the Utility of Convex Hull and Standard Ellipse Areas for Assessing Population Niche Widths from Stable Isotope Data
2013
Stable isotope analyses are increasingly employed to characterise population niche widths. The convex hull area (TA) in a δ¹³C–δ¹⁵N biplot has been used as a measure of isotopic niche width, but concerns exist over its dependence on sample size and associated difficulties in among-population comparisons. Recently a more robust method was proposed for estimating and comparing isotopic niche widths using standard ellipse areas (SEA), but this approach has yet to be tested with empirical stable isotope data. The two methods measure different kind of isotopic niche areas, but both are now widely used to characterise isotopic niche widths of populations. We used simulated data and an extensive e…
Trophic transfer of pesticides: The fine line between predator–prey regulation and pesticide–pest regulation
2020
International audience; Understanding pesticide impacts on populations of target/non-target species and communities is a challenge to applied ecology. When predators that otherwise regulate pest densities ingest prey contaminated with pesticides, this can suppress predator populations by secondary poisoning. It is, however, unknown how species relationships and protocols of treatments (e.g. anticoagulant rodenticide [AR]) interact to affect pest regulation.To tackle this issue, we modelled a heuristic non-spatialized system including montane water voles, specialist vole predators (stoats, weasels) and a generalist predator (red fox) which consumes voles, mustelids and other prey. By carryin…
Human-associated migration of Holarctic Saccharomyces uvarum strains to Patagonia
2020
Our results show that the greatest S. uvarum population diversity worldwide is observed in Patagonia, where strains of this species can be isolated from industrial and traditional fermentations as well as from natural environments. This greater Patagonian diversity is due to the presence of strains belonging to two genetically differentiated populations, South America B (SA-B), and Holarctic/South America A (H/SA-A). The H/SA-A population of Patagonia is directly related to apple fermentation environments, mainly from cider fermentations but also, to a lesser extent, from traditional apple chicha. Our data suggest that strains from the Holarctic population colonized Patagonia. This is possi…
The role of fish life histories in allometrically scaled food‐web dynamics
2019
Body size determines key ecological and evolutionary processes of organisms. Therefore, organisms undergo extensive shifts in resources, competitors, and predators as they grow in body size. While empirical and theoretical evidence show that these size‐dependent ontogenetic shifts vastly influence the structure and dynamics of populations, theory on how those ontogenetic shifts affect the structure and dynamics of ecological networks is still virtually absent. Here, we expand the Allometric Trophic Network (ATN) theory in the context of aquatic food webs to incorporate size‐structure in the population dynamics of fish species. We do this by modifying a food web generating algorithm, the nic…
Fine-Scale Population Differences in Atlantic Cod Reproductive Success: A Potential Mechanism for Ecological Speciation in a Marine Fish
2018
Abstract Successful resource‐management and conservation outcomes ideally depend on matching the spatial scales of population demography, local adaptation, and threat mitigation. For marine fish with high dispersal capabilities, this remains a fundamental challenge. Based on daily parentage assignments of more than 4,000 offspring, we document fine‐scaled temporal differences in individual reproductive success for two spatially adjacent (<10 km) populations of a broadcast‐spawning marine fish. Distinguished by differences in genetics and life history, Atlantic cod (Gadus morhua) from inner‐ and outer‐fjord populations were allowed to compete for mating and reproductive opportunities. After …
Ten principles for conservation translocations of threatened wood-inhabiting fungi
2020
Abstract Unlike for many other organism groups, conservation translocations of fungi are still rare. Encouraged by recent successful translocations, there is a growing interest in applying this conservation tool to threatened wood-inhabiting fungi. When combined with other conservation or restoration measures, translocation can be an effective measure for preventing further population decline in the short term, and species extinctions in the long term. Translocations can be appropriate for rare and specialist fungal species that occur as small local populations in isolated patches across fragmented landscapes, where there is a low likelihood of successful dispersal between distant host tree…
Plant-phenotypic changes induced by parasitoid ichnoviruses enhance the performance of both unparasitized and parasitized caterpillars
2021
Early Access; International audience; There is increasing awareness that interactions between plants and insects can be mediated by microbial symbionts. Nonetheless, evidence showing that symbionts associated with organisms beyond the second trophic level affect plant-insect interactions are restricted to a few cases belonging to parasitoid-associated bracoviruses. Insect parasitoids harbor a wide array of symbionts which, like bracoviruses, can be injected into their herbivorous hosts to manipulate their physiology and behavior. Yet, the function of these symbionts in plant-based trophic webs remains largely overlooked. Here we provide the first evidence of a parasitoid-associated symbiont…
Active Wild Food Practices among Culturally Diverse Groups in the 21st Century across Latgale, Latvia
2021
Simple Summary A study in the bordering region of Latvia took place in order to investigate wild plant food uses. In total 72 interviewees reported food uses. The most represented uses of recorded plants were recreational tea; for jam; as snacks and soup; and drink. Interviewees also reported loss of foraging practice due to the habitat change as for example in case of caraway and chamomile. The results indicated that part of the reason for the main use of wild plants were linked to diet diversification. Abstract Local ecological knowledge (LEK), including but not limited to the use of wild food plants, plays a large role in sustainable natural resource management schemes, primarily due to …
Dealing with physical barriers in bottlenose dolphin (Tursiops truncatus) distribution
2019
Abstract Worldwide, cetacean species have started to be protected, but they are still very vulnerable to accidental damage from an expanding range of human activities at sea. To properly manage these potential threats we need a detailed understanding of the seasonal distributions of these highly mobile populations. To achieve this goal, a growing effort has been underway to develop species distribution models (SDMs) that correctly describe and predict preferred species areas. However, accuracy is not always easy to achieve when physical barriers, such as islands, are present. Indeed, SDMs assume, if only implicitly, that the spatial effect is stationary, and that correlation is only depende…