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81.
82.
Despite a recent surge of interest in temporary lentic systems, a strong theory linking the biota to its environment has not
emerged. Using data from 10 temporary ponds at Mammoth Cave National Park, Kentucky, USA, we investigated how invertebrate
communities were structured along environmental gradients, both between and within ponds. Samples were collected with a benthic
corer in winter and spring, and a sweep net in spring. Six between-pond and two within-pond datasets were created. Between-pond
analyses yielded significant CCA’s with only one of the six data sets. The ranges of environmental variables (EV’s) within
ponds were often similar to the ranges of EV’s when averaged and compared between ponds. Some taxa were aggregated in a single
pond, and richness increased with pond area. The theory that richness increases with hydroperiod did not apply to these systems.
Within-pond analyses yielded more consistent relationships, with both CCA’s being significant. Sample depth was the best predictor
of invertebrate richness and abundance, with most taxa preferring shallow habitats. Richness and abundance were higher in
both shallow ponds and shallow areas of deep ponds than in deep areas of deep ponds. Standardizing sample depth may be an
effective way to remove this gradient as a confounding variable in future research. The presence of within-pond gradients,
possibly coupled with the limited dispersal and random colonization of tolerant taxa, makes between-pond comparisons difficult.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorised users.
Handling editor: S. Declerck 相似文献
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85.
Aino Juslén Juha Pykälä Saija Kuusela Lauri Kaila Jaakko Kullberg Jaakko Mattila Jyrki Muona Sanna Saari Pedro Cardoso 《Biodiversity and Conservation》2016,25(3):569-585
For the first time ever, the International Union for Conservation of Nature Red List Index for habitat types was calculated for an entire country, Finland. The RLIs were based on species threat assessments from 2000 and 2010 and included habitat definitions for all 10,131 species of 12 organism groups. The RLIs were bootstrapped to track statistically significant changes. The RLI changes of species grouped by habitats were negative for all habitat types except for forests and rural biotopes which showed a stable trend. Trends of beetles and true bugs were positive in rural and forest habitats. Other 16 observed trends of species group and habitat combinations were negative. Several trends observed were in accordance with studies focusing on particular taxa and habitats, and drivers for their change. This study demonstrates the usefulness of the RLI as a tool for observing habitat change based on species threat assessment data. 相似文献
86.
David B. Lindenmayer P. W. Lane P. S. Barton Mason Crane Karen Ikin Damian Michael Sachiko Okada 《Biodiversity and Conservation》2016,25(8):1587-1603
The long-term effectiveness of restored areas for biodiversity is poorly known for the majority of restored ecosystems worldwide. We quantified temporal changes in bird occurrence in restoration plantings of different ages and geometries, and compared observed patterns with a reference dataset from woodland remnants on the same farms as our plantings. Over time, bird species richness remained unchanged in spring but exhibited modest increases in winter. We found that wider plantings supported significantly greater bird species richness in spring and winter than narrow plantings. There was no evidence of a significant interaction between planting width and time. We recorded major temporal changes in the occurrence of a range of individual species that indicated a clear turnover of species as plantings matured. Our results further revealed marked differences in individual species occurrence between plantings and woodland remnants. Life-history attributes associated with temporal changes in the bird assemblage were most apparent in winter survey data, and included diet, foraging and nesting patterns, movement behaviour (e.g. migratory vs. dispersive), and body size. Differences in bird assemblages between plantings of different ages suggest that it is important that farms support a range of age classes of planted woodland, if the aim is to maximize the number of native bird species in restored areas. Our data also suggest that changes in the bird species occupying plantings of different ages can be anticipated in a broadly predictable way based on planting geometry (especially width) and key life-history attributes, particularly movement patterns and habitat and diet specialisation. 相似文献
87.
This article explores responses to the implementation of Russian sturgeon conservation policy in three fishing communities (in Dagestan, Kalmykia and the Volga River delta areas), along the Western and Northern coasts of the Caspian Sea. Enforcement of regulatory measures has led to complex socio-cultural responses. We show how social responses to conservation policy generate various forms of poaching. An analytical model of ‘soft’ and ‘hard’ forms of poaching is analyzed against three regulatory measures: introduction of specially designated fishing areas in Russia’s Caspian fisheries, border zone expansion and the ban on sturgeon fishing. We explain why in Kalmykia the policy led people to stop practicing hard forms of sturgeon fishing, while fishermen in Dagestan responded in a more complex manner by displaying resistance towards the new policies. 相似文献
88.
Se-Chan Kim Alexander Ghanem Heidi Stapel Klaus Tiemann Pascal Knuefermann Andreas Hoeft Rainer Meyer Christian Grohé Anne A Knowlton Georg Baumgarten 《BMC physiology》2007,7(1):5
Backgound
It has been reported that Toll-like receptor 4 (TLR4) deficiency reduces infarct size after myocardial ischemia/reperfusion (MI/R). However, measurement of MI/R injury was limited and did not include cardiac function. In a chronic closed-chest model we assessed whether cardiac function is preserved in TLR4-deficient mice (C3H/HeJ) following MI/R, and whether myocardial and systemic cytokine expression differed compared to wild type (WT). 相似文献89.
Background
Insulin is a therapeutic protein that is widely used for the treatment of diabetes. Its biological function was discovered more than 80 years ago and it has since then been characterized extensively. Crystallization of the insulin molecule has always been a key activity since the protein is often administered by subcutaneous injections of crystalline insulin formulations. Over the years, insulin has been crystallized and characterized in a number of crystal systems. 相似文献90.
Cassandre Leverrier Giana Almeida Lucia Espinosa-Mu noz Gérard Cuvelier 《Food biophysics》2016,11(3):235-247
This work investigates the impact of structural parameters on the rheological behaviour of apple purees. Reconstructed apple purees from 0 g/100 g up to 2.32 g/100 g of insoluble solids content and varying in particle size were prepared. Three different particle size distributions were obtained by mechanical treatment only, to modify both size and morphology of the particles without modifying the intrinsic rigidity of the cell walls. Rheological measurements showed that the insoluble solids content have a first order effect on the rheological behaviour of the suspensions: three concentrations domains were observed in both dynamic and flow measurements. A model is proposed for each domain. The existence of a weak network between particles is clearly shown over a critical concentration of insoluble solids (cell walls) depending on particle size distribution (semi-diluted domain). In a concentrated domain, particles are on close packing conditions and their apparent volume begin to shrink. Particle size and shape also play an important role on the rheological behaviour of reconstructed apple puree. Due to their irregular shape, cell clusters clog the medium at lower concentration compared to individual cells. 相似文献