179 research outputs found
Collembola diversity in the critically endangered Cape Flats Sand Fynbos and adjacent pine plantations
The replacement of indigenous vegetation by commercial alien plantations can strongly affect invertebrate
species richness and composition. This has been demonstrated for some invertebrate taxa in the
Fynbos vegetation of the Western Cape, but the response of litter-dwelling Collembola has not been
documented. Here we compared the richness and abundance of litter-dwelling Collembola assemblages
in Pinus radiata plantations and in adjacent rehabilitated Cape Flats Sand Fynbos (CFSF) in the Tokai
Forest Reserve, Western Cape, South Africa. A total of 48 Collembola morphospecies was identified, of
which 14 species were recorded exclusively from the pine plantations, and six exclusively from the CFSF.
Abundance and morphospecies richness was higher in the pine plantations than in the CFSF, with 34
morphospecies found in the CFSF, and 42 morphospecies in the pine plantations. Fourteen species were
likely invasive taxa, of which eight were found in CFSF, and 13 in the pine plantations. Multivariate analyses
indicated significant differences in the assemblages of the two habitat types based on abundance,
but using presence–absence data only, no difference was found. Significant relationships were found
between springtail richness and abundance and site humidity, which differed between the CFSF (drier)
and pine plantation (moister), likely accounting for the differences in richness and abundance among
habitat types
Interactions between rates of temperature change and acclimation affects latitudinal patterns of warming tolerance
CITATION: Allen, J. L. et al. 2016. Interactions between rates of temperature change and acclimation affects latitudinal patterns of warming tolerance. Conservation Physiology, 4,(1):cow053, doi:10.1093/conphys/cow053.The original publication is available at https://academic.oup.com/conphysCritical thermal limits form an increasing component of the estimation of impacts of global change on ectotherms. Whether any consistent patterns exist in the interactive effects of rates of temperature change (or experimental ramping rates) and acclimation on critical thermal limits and warming tolerance (one way of assessing sensitivity to climate change) is, however, far from clear. Here, we examine the interacting effects of ramping rate and acclimation on the critical thermal maxima (CTmax) and minima (CTmin) and warming tolerance of six species of springtails from sub-tropical, temperate and polar regions. We also provide microhabitat temperatures from 26 sites spanning 5 years in order to benchmark environmentally relevant rates of temperature change. Ramping rate has larger effects than acclimation on CTmax, but the converse is true for CTmin. Responses to rate and acclimation effects are more consistent among species for CTmax than for CTmin. In the latter case, interactions among ramping rate and acclimation are typical of polar species, less marked for temperate ones, and reduced in species from the sub-tropics. Ramping rate and acclimation have substantial effects on estimates of warming tolerance, with the former being more marked. At the fastest ramping rates (>1.0°C/min), tropical species have estimated warming tolerances similar to their temperate counterparts, whereas at slow ramping rates (<0.4°C/min) the warming tolerance is much reduced in tropical species. Rates of temperate change in microhabitats relevant to the springtails are typically <0.05°C/min, with rare maxima of 0.3–0.5°C/min depending on the site. These findings emphasize the need to consider the environmental setting and experimental conditions when assessing species’ vulnerability to climate change using a warming tolerance approach.https://academic.oup.com/conphys/article/4/1/cow053/2452292Publisher's versio
Identification of moaA3 gene in patient isolates of Mycobacterium tuberculosis in Kerala, which is absent in M. tuberculosis H37Rv and H37Ra
BACKGROUND: Tuberculosis is endemic to developing countries like India. Though the whole genome sequences of the type strain M. tuberculosis H37Rv and the clinical strain M. tuberculosis CDC1551 are available, the clinical isolates from India have not been studied extensively at the genome level. This study was carried out in order to have a better understanding of isolates from Kerala, a state in southern India. RESULTS: A PCR based strategy was followed making use of the deletion region primers to understand the genome level differences between the type strain H37Rv and the clinical isolates of M. tuberculosis from Kerala. PCR analysis of patient isolates using RD1 region primers revealed the amplification of a 386 bp region, in addition to the expected 652 bp amplicon. Southern hybridization of genomic DNA with the 386 bp amplicon confirmed the presence of this new region in a majority of the patient isolates from Kerala. Sequence comparison of this amplicon showed close homology with the moaA3 gene of M. bovis. In M. bovis this gene is present in the RvD5 region, an IS6110 mediated deletion that is absent in M. tuberculosis H37Rv. CONCLUSION: This study demonstrates the presence of moaA3 gene, that is absent in M. tuberculosis H37Rv and H37Ra, in a large number of local isolates. Whether the moaA3 gene provides any specific advantage to the field isolates of the pathogen is unclear. Field strains from Kerala have fewer IS6110 sequences and therefore are likely to have fewer IS6110 dependent rearrangements. But as deletions and insertions account for much of the genomic diversity of M. tuberculosis, the mechanisms of formation of sequence polymorphisms in the local isolates should be further examined. These results suggest that studies should focus on strains from endemic areas to understand the complexities of this pathogen
Adaptative Potential of the Lactococcus Lactis IL594 Strain Encoded in Its 7 Plasmids
The extrachromosomal gene pool plays a significant role both in evolution and in the environmental adaptation of bacteria. The L. lactis subsp. lactis IL594 strain contains seven plasmids, named pIL1 to pIL7, and is the parental strain of the plasmid-free L. lactis IL1403, which is one of the best characterized lactococcal strains of LAB. Complete nucleotide sequences of pIL1 (6,382 bp), pIL2 (8,277 bp), pIL3 (19,244 bp), pIL4 (48,979), pIL5 (23,395), pIL6 (28,435 bp) and pIL7 (28,546) were established and deposited in the generally accessible database (GeneBank). Nine highly homologous repB-containing replicons, belonging to the lactococcal theta-type replicons, have been identified on the seven plasmids. Moreover, a putative region involved in conjugative plasmid mobilization was found on four plasmids, through identification of the presence of mob genes and/or oriT sequences. Detailed bioinformatic analysis of the plasmid nucleotide sequences provided new insight into the repertoire of plasmid-encoded functions in L. lactis, and indicated that plasmid genes from IL594 strain can be important for L. lactis adaptation to specific environmental conditions (e.g. genes coding for proteins involved in DNA repair or cold shock response) as well as for technological processes (e.g. genes encoding citrate and lactose utilization, oligopeptide transport, restriction-modification system). Moreover, global gene analysis indicated cooperation between plasmid- and chromosome-encoded metabolic pathways
Biodiversity redistribution under climate change: Impacts on ecosystems and human well-being
Distributions of Earth’s species are changing at accelerating rates, increasingly driven by human-mediated climate change. Such changes are already altering the composition of ecological communities, but beyond conservation of natural systems, how and why does this matter? We review evidence that climate-driven species redistribution at regional to global scales affects
ecosystem functioning, human well-being, and the dynamics of climate change itself. Production of natural resources required for food security, patterns of disease transmission, and processes of carbon sequestration are all altered by changes in species distribution. Consideration of
these effects of biodiversity redistribution is critical yet lacking in most mitigation and adaptation strategies, including the United Nation’s Sustainable Development Goals
EstaciĂłn Experimental de Aula Dei. Memoria anual 2014
67 Pags.Esta memoria recoge la actividad cientĂfica de la EstaciĂłn Experimental de Aula Dei (EEAD-CSIC) durante el año 2014, conteniendo informaciĂłn especĂfica sobre las siguientes actividades de la EEAD-CSIC: Publicaciones (ISI y no ISI; Actas de congresos; Libros y CapĂtulos de Libro), Transferencia tecnolĂłgica, Tesis, Congresos, Cursos, Seminarios, Estancias, Actividades de cultura cientĂfica, Eventos. Incluye, además, un informe de financiaciĂłn, directorio del personal en activo durante el año y tabla-resumen de las estadĂsticas relacionadas con los procesos tĂ©cnicos y servicios de la Unidad TĂ©cnica de Biblioteca y DocumentaciĂłn.Peer reviewe
Reconstruction of Gene Regulatory Networks from Gene Expression Data Using Decoupled Recurrent Neural Network Model
Are luminescent bacteria suitable for online detection and monitoring of toxic compounds in drinking water and its sources?
Biosensors based on luminescent bacteria may be valuable tools to monitor the chemical quality and safety of surface and drinking water. In this review, an overview is presented of the recombinant strains available that harbour the bacterial luciferase genes luxCDABE, and which may be used in an online biosensor for water quality monitoring. Many bacterial strains have been described for the detection of a broad range of toxicity parameters, including DNA damage, protein damage, membrane damage, oxidative stress, organic pollutants, and heavy metals. Most lux strains have sensitivities with detection limits ranging from milligrams per litre to micrograms per litre, usually with higher sensitivities in compound-specific strains. Although the sensitivity of lux strains can be enhanced by various molecular manipulations, most reported detection thresholds are still too high to detect levels of individual contaminants as they occur nowadays in European drinking waters. However, lux strains sensing specific toxic effects have the advantage of being able to respond to mixtures of contaminants inducing the same effect, and thus could be used as a sensor for the sum effect, including the effect of compounds that are as yet not identified by chemical analysis. An evaluation of the suitability of lux strains for monitoring surface and drinking water is therefore provided
Stable and fluctuating temperature effects on the development rate and survival of two malaria vectors, Anopheles arabiensis and Anopheles funestus
Global monitoring of soil animal communities using a common methodology.
Here we introduce the Soil BON Foodweb Team, a cross-continental collaborative network that aims to monitor soil animal communities and food webs using consistent methodology at a global scale. Soil animals support vital soil processes via soil structure modification, consumption of dead organic matter, and interactions with microbial and plant communities. Soil animal effects on ecosystem functions have been demonstrated by correlative analyses as well as in laboratory and field experiments, but these studies typically focus on selected animal groups or species at one or few sites with limited variation in environmental conditions. The lack of comprehensive harmonised large-scale soil animal community data including microfauna, mesofauna, and macrofauna, in conjunction with related soil functions, microbial communities, and vegetation, limits our understanding of biological interactions in soil systems and how these interactions affect ecosystem functioning. To provide such data, the Soil BON Foodweb Team invites researchers worldwide to use a common methodology to address six long-term goals: (1) to collect globally representative harmonised data on soil micro-, meso-, and macrofauna communities, (2) to describe key environmental drivers of soil animal communities and food webs, (3) to assess the efficiency of conservation approaches for the protection of soil animal communities, (4) to describe soil food webs and their association with soil functioning globally, (5) to establish a global research network for soil biodiversity monitoring and collaborative projects in related topics, (6) to reinforce local collaboration networks and expertise and support capacity building for soil animal research around the world. In this paper, we describe the vision of the global research network and the common sampling protocol to assess soil animal communities and advocate for the use of standard methodologies across observational and experimental soil animal studies. We will use this protocol to conduct soil animal assessments and reconstruct soil food webs at sites associated with the global soil biodiversity monitoring network, Soil BON, allowing us to assess linkages among soil biodiversity, vegetation, soil physico-chemical properties, climate, and ecosystem functions. In the present paper, we call for researchers especially from countries and ecoregions that remain underrepresented in the majority of soil biodiversity assessments to join us. Together we will be able to provide science-based evidence to support soil biodiversity conservation and functioning of terrestrial ecosystems
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