The influence of stream age and environmental variables in structuring meiofaunal assemblages in recently deglaciated streams

Robertson, A.; Milner, Alexander M.

doi:10.4319/lo.2006.51.3.1454

Cited by 28 publications

(31 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several studies assessed complexity as variability in substrate particle size (e.g., Robertson & Milner, 2006); whereas others described substrate heterogeneity using diversity and evenness indices (Brown, 2003) and fractal dimension (Robson & Chester, 1999). Sanson et al (1995) estimated surface complexity using image analysis tool with circles of different sizes on digital profiles of streambeds.…”

Section: Abiotic Complexitymentioning

confidence: 99%

Habitat complexity: approaches and future directions

2011

View full text Add to dashboard Cite

Habitat complexity is one of the most important factors structuring biotic assemblages, yet we still lack basic understanding of the underlying mechanisms. Although it is one of the primary targets in conservation management, no methods are available for comparing complexity across ecosystems, and system-specific qualitative assessment predominates. Despite its overwhelming importance for faunal diversity and abundance, there has been surprisingly little interest in examining its effects on other community and ecosystem attributes. We discuss possibilities of such effects, outlining potentially fruitful areas for future research, and argue that complexity may be implicated in community persistence and ecosystem stability by acting as a decoupling mechanism in predator-prey interactions. We provide a brief overview of methods used to quantify complexity in different ecosystems, highlighting contributions of the current issue of Hydrobiologia, and discuss potential application of these approaches for cross-ecosystem comparisons. Better understanding of the role of habitat complexity resulting from such comparisons is critically important for preservation of biodiversity and ecosystem function in an era of unprecedented habitat loss.

show abstract

Section: Abiotic Complexitymentioning

confidence: 99%

Habitat complexity: approaches and future directions

2011

View full text Add to dashboard Cite

show abstract

“…2) and channel stability. For example, microcrustacean persistence in streams results from a combined strategy of high resilience (due to rapid recruitment), and the adoption of ''refuge as habitat'' and is dependent on habitat diversity (Robertson et al 1995, Robertson 2000, Robertson and Milner 2006. The additional chironomid taxa found at site 1 compared to Wolf Point Creek may result from their wide dispersal capacity; Stonefly Creek is closer than Wolf Point Creek to possible colonizer sources in older streams of the northwest arm, and adult insects could disperse up glacial valleys rather than over high mountain ridges.…”

Section: Invertebratesmentioning

confidence: 99%

Evolution of a stream ecosystem in recently deglaciated terrain

Milner

Robertson

Brown

et al. 2011

Ecology

View full text Add to dashboard Cite

Abstract. Climate change and associated glacial recession create new stream habitat that leads to the assembly of new riverine communities through primary succession. However, there are still very few studies of the patterns and processes of community assembly during primary succession for stream ecosystems. We illustrate the rapidity with which biotic communities can colonize and establish in recently formed streams by examining Stonefly Creek in Glacier Bay, Alaska (USA), which began to emerge from a remnant glacial ice mass between 1976 and 1979. By 2002, 57 macroinvertebrate and 27 microcrustacea species had become established. Within 10 years of the stream's formation, pink salmon and Dolly Varden charr colonized, followed by other fish species, including juvenile red and silver salmon, Coast Range sculpin, and sticklebacks. Stable-isotope analyses indicate that marine-derived nitrogen from the decay of salmon carcasses was substantially assimilated within the aquatic food web by 2004. The findings from Stonefly Creek are compared with those from a long-term study of a similarly formed but older stream (12 km to the northeast) to examine possible similarities in macroinvertebrate community and biological trait composition between streams at similar stages of development. Macroinvertebrate community assembly appears to have been initially strongly deterministic owing to low water temperature associated with remnant ice masses. In contrast, microcrustacean community assembly appears to have been more stochastic. However, as stream age and water temperature increased, macroinvertebrate colonization was also more stochastic, and taxonomic similarity between Stonefly Creek and a stream at the same stage of development was ,50%. However the most abundant taxa were similar, and functional diversity of the two communities was almost identical. Tolerance is suggested as the major mechanism of community assembly. The rapidity with which salmonids and invertebrate communities have become established across an entire watershed has implications for the conservation of biodiversity in freshwater habitats.

show abstract

“…For smaller invertebrates (e.g. meiofaunal copepods), habitat availability might be a stronger determinant of establishment success because dispersal ability may be high owing to movement of these organisms by birds and mammals acting as vectors (Robertson & Milner 2006). …”

Section: Non-random Species Change In Fresh Waters and The Fragmentatmentioning

confidence: 99%

Climate change and freshwater ecosystems: impacts across multiple levels of organization

Woodward

Perkins

Brown

2010

Phil. Trans. R. Soc. B

1,047

767

View full text Add to dashboard Cite

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 focused on individuals or species populations, rather than the higher levels of organization (i.e. communities, food webs, ecosystems). We propose that an understanding of the connections between these different levels, which are all ultimately based on individuals, can help to develop a more coherent theoretical framework based on metabolic scaling, foraging theory and ecological stoichiometry, to predict the ecological consequences of climate change. For instance, individual basal metabolic rate scales with body size (which also constrains food web structure and dynamics) and temperature (which determines many ecosystem processes and key aspects of foraging behaviour). In addition, increasing atmospheric CO 2 is predicted to alter molar CNP ratios of detrital inputs, which could lead to profound shifts in the stoichiometry of elemental fluxes between consumers and resources at the base of the food web. The different components of climate change (e.g. temperature, hydrology and atmospheric composition) not only affect multiple levels of biological organization, but they may also interact with the many other stressors to which fresh waters are exposed, and future research needs to address these potentially important synergies.

show abstract

The influence of stream age and environmental variables in structuring meiofaunal assemblages in recently deglaciated streams

Cited by 28 publications

References 42 publications

Habitat complexity: approaches and future directions

Habitat complexity: approaches and future directions

Evolution of a stream ecosystem in recently deglaciated terrain

Climate change and freshwater ecosystems: impacts across multiple levels of organization

Contact Info

Product

Resources

About