Search results for "ECOSYSTEM"
showing 10 items of 1752 documents
Data from: Functional structure of European forest beetle communities is enhanced by rare species
2022
From article abstract: https://doi.org/10.1016/j.biocon.2022.109491 ABSTRACT Biodiverse communities have been shown to sustain high levels of multifunctionality and thus a loss of species likely negatively impacts ecosystem functions. For most taxa, however, the roles of individual species are poorly known. Rare species, often the most likely to go extinct, may have unique traits leading to unique functional roles. Alternatively, rare species may be functionally redundant, such that their loss would not disrupt ecosystem functions. We quantified the functional role of rare species by using capture records of wood-living (saproxylic) beetle species, combined with recent databases of their mo…
The ecosystem of the foreign language learner : selected issues
2015
This volume examines selected aspects of the foreign language learning process from an ecological perspective, adopting a holistic view on complex interrelations among and within organisms (L2 language learners) and their milieus (family, school and society). First of all, the personal ecosystem of the learner is taken into consideration, whereby two powerful influences are intertwined: cognitive and affective aspects. The learning space formed by the individual is largely shaped by their affective states coexisting in conjunction with their cognitive processes. Moreover, this specific space is also modified by a wider array of other personal ecosystems or those of cultures. Hence, the ecos…
Contrasting behavioural responses of two egg parasitoids to buckwheat floral scent is reflected in field parasitism rates
2017
The use of food supplements in conservation biological control (CBC) programmes is considered an essential element for increasing parasitoid fitness and their population density leading to an increase in overall parasitism levels. However, non-crop habitats that substitute the necessary resources for natural enemies have not always achieved the desired effects. It is suggested that the composition of flower strips in agricultural systems around/in agricultural fields plays an important role because not all plant species are equally suitable and the consumption of food resources by parasitoids can shape direct and indirect interactions with other arthropods and the community complex. We deve…
Dynamics of two competing species in the presence of Lévy noise sources
2010
We consider a Lotka-Volterra system of two competing species subject to multiplicative alpha-stable Lévy noise. The interaction parameter between the species is a random process which obeys a stochastic differential equation with a generalized bistable potential in the presence both of a periodic driving term and an additive alpha-stable Lévy noise. We study the species dynamics, which is characterized by two different regimes, exclusion of one species and coexistence of both. We find quasi-periodic oscillations and stochastic resonance phenomenon in the dynamics of the competing species, analysing the role of the Lévy noise sources.
Pulsed-Resource Dynamics Constrain the Evolution of Predator-Prey Interactions
2011
Although temporal variability in the physical environment plays a major role in population fluctuations, little is known about how it drives the ecological and evolutionary dynamics of species interactions. We studied experimentally how extrinsic resource pulses affect evolutionary and ecological dynamics between the prey bacterium Serratia marcescens and the predatory protozoan Tetrahymena thermophila. Predation increased the frequency of defensive, nonpigmented prey types, which bore competitive costs in terms of reduced maximum growth rate, most in a constant-resource environment. Furthermore, the predator densities of the pulsed-resource environment regularly fluctuated above and below …
The effect of automated taxa identification errors on biological indices
2017
In benthic macroinvertebrate biomonitoring systems, the target is to determine the status of ecosystems based on several biological indices. To increase cost-efficiency, computer-based taxa identification for image data has recently been developed. Taxa identification errors can, however, have strong effects on the indices and thus on the determination of the ecological status. In order to shift the biomonitoring process towards automated expert systems, we need a clear understanding on the bias caused by automation. In this paper, we examine eleven classification methods in the case of macroinvertebrate image data and show how their classification errors propagate into different biological…
An introduction to knowledge computing
2014
This paper deals with the challenges related to self-management and evolution of massive knowledge collections. We can assume that a self-managed knowledge graph needs a kind of a hybrid of: an explicit declarative self-knowledge (as knowledge about own properties and capabilities) and an explicit procedural self-knowledge (as knowledge on how to utilize own properties and the capabilities for the self-management).We offer an extension to a traditional RDF model of describing knowledge graphs according to the Semantic Web standards so that it will also allow to a knowledge entity to autonomously perform or query from remote services different computational executions needed. We also introdu…
Innovations and ecosystems : a characterization of Smart Tampere innovation ecosystem
2019
Master's thesis Innovative governance and public management ME523 - University of Agder 2019 The following thesis focuses on innovation ecosystem. As described in thefirst section, innovations are of great importance for tackling global challenges such as climate change andthus,of relevancy for the regional economic development. The growing importance of innovationshas motivated numerous new approaches to innovation management, especiallyin the last years the approach ofinnovation ecosystem.In the secondsection, the concept of innovation ecosystem is introduced and the most relevantconcepts from the literature are discussed. It thereby compares innovation ecosystem to other concepts such as…
Designing, Developing, and Implementing Software Ecosystems: Towards a Step-wise Guide
2016
The notion of software ecosystems has been popular both in research and industry for more than a decade, but how software ecosystems are created still remains unclear. This becomes more of a challenge if one examines the “creation” of ecosystems that have high probability in surviving in the future, i.e. with respect to ecosystem health. In this paper, we focus on the creation of software ecosystems and propose a process for designing, developing, and establishing software ecosystems based on three basic steps and a set of activities for each step. We note that software ecosystem research identifies that ecosystems typically emerge from either a company deciding to allow development on thei…
Functional consequences of prey acclimation to ocean acidification for the prey and its predator
2015
Ocean acidification is the suite of chemical changes to the carbonate system of seawater as a consequence of anthropogenic carbon dioxide (CO2) emissions. Despite a growing body of evidences demonstrating the negative effects of ocean acidification on marine species, the consequences at the ecosystem level are still unclear. One factor limiting our ability to upscale from species to ecosystem is the poor mechanistic understanding of the functional consequences of the observed effects on organisms. This is particularly true in the context of species interactions. The aim of this work was to investigate the functional consequence of the exposure of a prey (the mussel Brachidontes pharaonis) t…