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Book Chapter Zooplankton of Lake Kivu
Book Chapter Zooplankton of Lake Kivu

... Dumont (1986) described the sardine introduction as an ecological disaster, which caused the disappearance of a major grazer, the cladoceran Daphnia curvirostris Eylmann 1887, and a decrease in size and abundance of the remaining crustaceans. However, zooplankton records of Lake Kivu, on which Dumon ...
- Wiley Online Library
- Wiley Online Library

... and dynamics over time. To acquire better information, we should target invasions of known ages, including new invasions, and gather data as the invasion progresses or, alternatively, substitute space for time by evaluating pathogen richness and abundance at sites along a chronosequence of invasion ...
Competition hierarchy, transitivity and additivity: investigating the
Competition hierarchy, transitivity and additivity: investigating the

... monocultures and pairwise mixtures because competitive effects were not additive. This had implications for community stability at equilibrium: all two-species systems were stable, both fertilised and unfertilised, while the three-species system was only stable when fertilised. This stability under ...
DEFORESTATION PATTERNS AND HUMMINGBIRD DIvERSITy IN
DEFORESTATION PATTERNS AND HUMMINGBIRD DIvERSITy IN

... Several studies have identified niche breadth i.e. the range of resources utilized by a species as a determining factor in terms of ecological resilience (Swihart et al., 2006), and thus also decide a species geographical range (Slatyer et al., 2013). Geographically separated populations of the sam ...
Eutrophication causes speciation reversal in whitefish adaptive
Eutrophication causes speciation reversal in whitefish adaptive

... case of introgressive hybridization is speciation reversal4, in which changes in selection regimes increase gene flow between sympatric species, thus eroding genetic and ecological differences. Speciation reversal may be particularly important in adaptive radiations with recently diverged sympatric ...
Common Name: COOSAWATTEE CRAYFISH Scientific Name
Common Name: COOSAWATTEE CRAYFISH Scientific Name

... the rock and disturbing the substrate beneath it. If a crayfish is hiding underneath the rock, it will likely move into the net. Shocking downstream into a seine net with a backpack electroshocker is also effective. Collections in spring or fall are more likely to produce males in reproductive condi ...
DR on Adoption of Guidance and Definitions Rev1
DR on Adoption of Guidance and Definitions Rev1

... f. Whether disturbance effects ultimately impact on population size depends not only on whether these affect survival and/or reproductive success, but also whether density-dependent processes operate within the population. This will determine whether the population will ‘compensate’ for losses throu ...
English
English

... assessment of the adequacy of observation systems to provide the data needed for these targets (GEO BON 2011). It concluded that though a wide range of biodiversity information was available, it be unlikely that it would be possible to completely monitor progress towards the achievement of the Aichi ...
Using the ESS Maximum Principle to Explore Root
Using the ESS Maximum Principle to Explore Root

... Competition between plants that differ in root-shoot allocation has been modelled using consumer-resource equations where competition occurs only through the utilization of resources. Provided that such models can be put into an evolutionary game setting, we show that conditions for coexistence can ...
Ecology and Evolution Affect Network Structure
Ecology and Evolution Affect Network Structure

... early analyses of network topology used network statistics (e.g., connectivity, nestedness) that considered only binary connections between species, that is, a presence/absence interaction matrix (but see Vazquez et al. 2007). However, an analysis of network properties based on an index of reciproca ...
Animal species diversity driven by habitat heterogeneity
Animal species diversity driven by habitat heterogeneity

... habitat heterogeneity/diversity and animal species diversity. However, empirical support for this relationship is drastically biased towards studies of vertebrates and habitats under anthropogenic influence. In this paper, we show that ecological effects of habitat heterogeneity may vary considerabl ...
Lepidopteran Communities in Two Forest Ecosystems During the
Lepidopteran Communities in Two Forest Ecosystems During the

... 1984). Indicator species analysis (Dufrene and Legendre 1997) was also performed to identify species and guilds that were important indicators of differences among seasons, ecosystems, or levels of defoliation. Nonmetric Multidimensional Scaling Ordination. The original community matrix was transfor ...
conclusions from phytoplankton surveys
conclusions from phytoplankton surveys

... phytoplankton, can be easily reformulated; for example, biotic events may be stressed; weather can be replaced by seasonal cyclicity or different kinds of climatic fluctuations. Disturbance does not exist per se. It is impossible to define it without involving the entity that is affected in the defi ...
19-Population ecology
19-Population ecology

... Another tool used by population ecologists is a survivorship curve, which is a graph of the number of individuals surviving at each age interval versus time. These curves allow us to compare the life histories of different populations (Figure 19.4). There are three types of survivorship curves. In a ...
pptx
pptx

... “If some mechanism promotes the coexistence of two or more species, each species must be able to increase when it is rare and the others are at their typical abundances; this invasibility criterion is fundamental evidence for species coexistence regardless of the mechanism.” “some subset of the co-o ...
Designing marine reserves for interacting species: Insights
Designing marine reserves for interacting species: Insights

... and Wennergren, 1995), local dispersal in spatially explicit simulations (e.g. Dytham, 1994; Tilman et al., 1997), different patterns of fragmentation in simulations with local dispersal (Dytham, 1995b,a; Tilman et al., 1997), delayed reproduction (Tilman et al., 1997), distance-dependent colonizati ...
Quantifying and testing coexistence mechanisms arising from
Quantifying and testing coexistence mechanisms arising from

... recruitment alter the competition that occurs during recruitment by altering the density of individuals that are competing for the resources needed for recruitment. For example, if more tree seedlings appear in the forest due to environmental effects, competition between seedlings can be expected to ...
pptx
pptx

... “If some mechanism promotes the coexistence of two or more species, each species must be able to increase when it is rare and the others are at their typical abundances; this invasibility criterion is fundamental evidence for species coexistence regardless of the mechanism.” “some subset of the co-o ...
Beyond species loss: the extinction of ecological interactions in a
Beyond species loss: the extinction of ecological interactions in a

... When delta is negative, interactions are lost at a lower rate than species along the gradient of habitat loss, and thus, the interaction balance is positive (Fig. 1c). We call this situation interaction surplus. In contrast, when delta is positive, interactions are lost at a higher rate than species ...
Beyond species loss: The extinction of ecological
Beyond species loss: The extinction of ecological

... When delta is negative, interactions are lost at a lower rate than species along the gradient of habitat loss, and thus, the interaction balance is positive (Fig. 1c). We call this situation interaction surplus. In contrast, when delta is positive, interactions are lost at a higher rate than species ...
Propagule pressure: a null model for biological invasions
Propagule pressure: a null model for biological invasions

... primarily a matter of spatial scale. For example, virtually all experimental studies of establishment examined NIS that were obtained locally, thus they are really testing local spread rather than establishment from a distant native source region. Owing to the large number of studies included in our ...
A multi-agent ecosystem model for studying changes in a tropical
A multi-agent ecosystem model for studying changes in a tropical

... allows a quantitative estimate of MPA spill-over. To achieve this purpose, we adapted an existing ecosystem model, OSMOSE (Object-oriented simulator of marine biodiversity exploitation), to the specific case of the presence of fish with multiple life histories. The adapted model can manage 4 main ca ...
Scaling environmental change through the community
Scaling environmental change through the community

... to the challenge of scaling processes from individuals to ecosystems through the community level in the context of environmental change. The use of traits or groupings to predict functional response to environmental change has developed rapidly over the last two decades (Grime et al., 1988; Woodward ...
Downloaded
Downloaded

... that we could understand the coexistence of species by identifying and distinguishing between equalizing and stabilizing forces [35]. Species differences affect both of these forces [36]. On the one hand, differences between species can lead to differences in fitness, which can lead to competitive e ...
Nearshore fish assemblages associated with introduced predatory
Nearshore fish assemblages associated with introduced predatory

... constructed using chi‐square distance. Chi‐square distance was chosen over other resemblance measures (such as Jaccard or Copyright # 2011 John Wiley & Sons, Ltd and Her Majesty the Queen in Right of Canada. ...
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Occupancy–abundance relationship

In ecology, the occupancy–abundance (O–A) relationship is the relationship between the abundance of species and the size of their ranges within a region. This relationship is perhaps one of the most well-documented relationships in macroecology, and applies both intra- and interspecifically (within and among species). In most cases, the O–A relationship is a positive relationship. Although an O–A relationship would be expected, given that a species colonizing a region must pass through the origin (zero abundance, zero occupancy) and could reach some theoretical maximum abundance and distribution (that is, occupancy and abundance can be expected to co-vary), the relationship described here is somewhat more substantial, in that observed changes in range are associated with greater-than-proportional changes in abundance. Although this relationship appears to be pervasive (e.g. Gaston 1996 and references therein), and has important implications for the conservation of endangered species, the mechanism(s) underlying it remain poorly understood
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