Spatial Variation in Abundance Created by Stochastic Temporal Variation
6
Citation
0
Reference
10
Related Paper
Citation Trend
Abstract:
A central question in ecology is explaining spatial variation in the abundance of species. Patterns of spatial variation in abundance can often be explained by spatial variation in the environment, including resource availability, climatic variables, and other factors that influence a species' reproduction and survival. We show that spatial patterns in abundance may also be driven by temporal environmental variation, in the absence of any fixed spatial environmental variation. To illustrate this, we build on work by J. H. Brown, D. W. Mehlman, and G. C. Stevens, who demonstrated spatial patterns in bird abundances that can be explained by fixed spatial variation in the environment. Using a pair of simple stochastic models of bird population dynamics, we show that similar patterns can be generated through temporal environmental variation that has no fixed spatial component. This occurs when population dynamics are characterized by very weak density dependence, so that population densities exhibit near-random-walk behavior. Because similar patterns of spatial variation in species' abundances can be produced by either fixed spatial environmental variation or spatiotemporal environmental variation, we argue that interpreting spatial variation in abundance may sometimes require understanding temporal variation in abundance.Keywords:
Variation (astronomy)
Cite
Firstly,according to variation contents,the paper divides variation into operating range variation,construction condition variation,design variation,construction variation and technique standards variation. Contraposing to different content variation,the paper puts forward dissimilar control methods. According to the property of project variation,the paper divides variation into fatal variation,important variation and general variation,and points out that we can control variation effectively by establishing dissimilar authority of project variation examination and approval. Finally,according to the urgency of variation,the paper divides variation into variation under urgent circumstance and variation under not urgent circumstance,and puts forward that we can control these variation by different procedure.
Variation (astronomy)
Process Variation
Cite
Citations (0)
Summary The species–area relationship, which is closely linked with the more general species‐energy theory, is one of the most well‐known patterns in geographical ecology, but the underlying causes remain contentious. The more individuals hypothesis ( MIH ) articulates a causal path from resource availability to population abundance to species richness. The MIH has been tested with a range of taxa including plants, invertebrates and land birds but never with migratory waterbirds. Using multiyear simultaneous survey data of wintering waterbirds in 10 lakes at Poyang Lake, China, and remotely sensed habitat condition measurements, we applied structural equation modelling ( SEM ) to test three causal paths: (A) good habitat conditions (e.g. habitat availability and heterogeneity) attract more species (high richness); (B) habitat conditions promote abundance (more individuals); and (C) habitat conditions promote abundance, which in turn increases richness. We also modelled responses of species richness and abundance to habitat conditions using generalised additive mixed modelling ( GAMM ) to assess their co‐variation. While our analysis confirmed the first two paths, we found no support for the third, which is the central postulate of the MIH . In addition, in agreement with GAMM , SEM indicated that species richness was more closely related to habitat quality than to abundance. Our findings suggest that wintering waterbird species richness and abundance are two intrinsic community indices that covary with environmental variables.
Spatial heterogeneity
Cite
Citations (10)
AbstractThe names of 1024 American automobiles are analyzed according to register variation, diachronic variation and manufacturer variation. Variation through such linguistic means as structural complexity, metonymy and iconicity is shown to not only reflect social realities of automobile producers and consumers but to actively contribute to constructing these realities as well.
Variation (astronomy)
Iconicity
Cite
Citations (7)
Variation is an important issue of sociolinguistics.According to the variation view of sociolinguistics,grammatical items change under the influence of social factors.Compared with the research on phonetic variation,the research on grammatical variation is weaker.This article presents a review of the literature both at home and abroad on grammatical or syntactic variation.Some propositions for Chinese researchers on grammatical or syntactic variation are put forward at the end of the paper.
Variation (astronomy)
Sociolinguistics
Cite
Citations (0)
Variation occurs when a language has two or more ways of achieving the same communicative goal. Cases of variation have been approached in very different ways by two different groups of linguists. Variationists assume that variation is natural and common. On this view, change is due to naturally occurring variation interacting with language-external forces. Functionalists assume that variation is anomalous. On this view, change may reflect a language-internal drive to eradicate variation. In this paper, it is argued that these conflicting views can be reconciled by considering how variation functions in the broader context of the grammar. Drawing on a case study into the prepositional complements following emotion adjectives, it is proposed that variation (as Variationists maintain) is natural and that languages have no intrinsic tendency to reduce variability. Nevertheless, the synchronic availability and historical development of specific variants is (as Functionalists maintain) also internally motivated, typically by analogical relations.
Variation (astronomy)
Language Change
Cite
Citations (6)
Empirical and experimental work has yielded burgeoning evidence of intra-individual variation drawing on a variety of analytical frameworks and methodological approaches. A systematic review of intra-individual variation is thus timely both to provide guidance for researchers wishing to interpret and understand intra-individual variation and to provide some theoretical and methodological resources to evaluate the rapidly growing body of literature on intra-individual variation. The present chapter thus untangles intra-individual variation both terminologically and conceptually. We survey the scholarly discussion and evaluation of intra-individual variation in the interdisciplinary discourse of theoretical linguistic frameworks and empirical studies. By sketching previous research, we systematise various types of intra-individual and derive the proposal for a model of intra-individual variation followed by some remarks about the application of intra-individual variation.
Variation (astronomy)
Empirical Research
Cite
Citations (2)
Rocky intertidal systems are useful to study the influence of measurement scale on spatial biological variation in community structure. Vertical biological variation across elevations (triggered by tides) has typically been found higher than horizontal (alongshore) variation at local scales but lower than horizontal variation at regional scales. In those studies, alongshore environmental variation increased with scale. We surveyed the Canadian and Chilean coasts at those scales but with a limited underlying alongshore environmental variation and found that horizontal biological variation was never higher than vertical biological variation. Predicting spatial scales of biological variation should thus consider the underlying environmental variation. These photographs illustrate the article “Interhemispheric comparison of scale-dependent spatial variation in the structure of intertidal rocky-shore communities” by Alexis M. Catalán, Nelson Valdivia, and Ricardo A. Scrosati published in Ecosphere. https://doi.org/10.1002/ecs2.3068.
Variation (astronomy)
Intertidal ecology
Temporal scales
Geographic variation
Rocky shore
Cite
Citations (0)
Cross-talks and sketches are two important forms of language art in our country. They are popular with a wide range of audiences around the country due to their humorous language. Language variation is a very important means of creating humor effect. In cross-talks and sketches,various forms of language variation, including phonetic variation, lexical variation,grammar variation, semantic variation,stylistic variation and pragmatic variation,are applied to realize humor effect.
Variation (astronomy)
Cite
Citations (0)
Variation (astronomy)
Language Change
Cite
Citations (5)
The idioms become a language form that people love to see and hear for the fixed structure and the fusion meaning.The idioms' use includes the conventional use and the variation use.This paper primarily treats the idioms' variation use based on the studies of predecessors,and we mainly distinguish between the idioms' form variation and the idioms' meaning variation.It mainly analyses the three basic types and the rhetorical characteristics of the idioms' variation use.
Variation (astronomy)
Cite
Citations (0)