Ecology and biogeography of free-living nematodes associated with chemosynthetic environments in the deep sea: A review

Background: Here, insight is provided into the present knowledge on free-living nematodes associated with chemosynthetic environments in the deep sea. It was investigated if the same trends of high standing stock, low diversity, and the dominance of a specialized fauna, as observed for macro-invertebrates, are also present in the nematodes in both vents and seeps.Methodology: This review is based on existing literature, in combination with integrated analysis of datasets, obtained through the Census of Marine Life program on Biogeography of Deep-Water Chemosynthetic Ecosystems (ChEss).Findings: Nematodes are often thriving in the sulphidic sediments of deep cold seeps, with standing stock values ocassionaly exceeding largely the numbers at background sites. Vents seem not characterized by elevated densities. Both chemosynthetic driven ecosystems are showing low nematode diversity, and high dominance of single species. Genera richness seems inversely correlated to vent and seep fluid emissions, associated with distinct habitat types. Deep-sea cold seeps and hydrothermal vents are, however, highly dissimilar in terms of community composition and dominant taxa. There is no unique affinity of particular nematode taxa with seeps or vents.Conclusions: It seems that shallow water relatives, rather than typical deep-sea taxa, have successfully colonized the reduced sediments of seeps at large water depth. For vents, the taxonomic similarity with adjacent regular sediments is much higher, supporting rather the importance of local adaptation, than that of long distance distribution. Likely the ephemeral nature of vents, its long distance offshore and the absence of pelagic transport mechanisms, have prevented so far the establishment of a successful and typical vent nematode fauna. Some future perspectives in meiofauna research are provided in order to get a more integrated picture of vent and seep biological processes, including all components of the marine ecosystem

Monitoring der Umstellung auf den Ökologischen Landbau

A long term field monitoring concerning the development of organic farming is performed at the bio-farm "Rutzendorf" of the BVW GmbH in the Marchfeld region East of Vienna. It is an interdisciplinary project of eleven scientific institutes which started in 2003. The aims of the project are: examination of changes concerning soil and plant parameters with the conversion to organic farming; investigation of the effects of different organic fertilisation systems (green manure, communal green forage compost, farmyard manure) on soil properties and on the development of crops; analysis of existing biotops (hedges and field stripes) on the farm and planning and selective realization of new biotops with the aim of enhancing the biodiversity of the area

Auswirkungen unterschiedlicher Düngungssysteme im Ökologischen Landbau auf Bodenparameter und Entwicklung der Pflanzen

Auf dem landwirtschaftlichen Betrieb Rutzendorf soll ein umfassendes Langzeitmonitoring zur Entwicklung des biologischen Landbaus eingerichtet werden. Ein wissenschaftliches Konzepts soll erarbeitet und zum Teil schon umgesetzt werden. Die Wirkungen der Umstellung auf Ökologischen Landbau auf Boden, Wasser, Flora und Fauna soll anhand ausgewählter Eigenschaften erfasst werden. Entsprechend der Konzeption des Betriebs (vgl. ¿Konzept Biobetrieb Rutzendorf¿, Bericht an das BMLFUW, IfÖL, BOKU, März 2002) sollen drei Düngungsvarianten verglichen werden. Die Bedeutung verschiedener vorhandener Biotope (Gehölzstreifen, Hecken, ...) soll charakterisiert und neue, ergänzende Biotope geplant und angelegt werden. Versuchsort und -gegenstand ist der landwirtschaftliche Betrieb Rutzendorf der Bundesversuchswirtschaft Ges.m.b.H. Durchgeführt wird ein Monitoring der Auswirkungen von Düngungsvarianten unter Beibehaltung der Fruchtfolge sowie der Umstellung des Betriebes auf die Umwelt, Produktion und Wirtschaftlichkei

Laser wakefield acceleration with mid-IR laser pulses

We report on the first results of laser plasma wakefield acceleration driven by ultrashort mid-infrared laser pulses (\lambda= 3.9 \mu m, 100 fs, 0.25 TW), which enable near- and above-critical density interactions with moderate-density gas jets. Relativistic electron acceleration up to ~12 MeV occurs when the jet width exceeds the threshold scale length for relativistic self-focusing. We present scaling trends in the accelerated beam profiles, charge and spectra, which are supported by particle-in-cell simulations and time-resolved images of the interaction. For similarly scaled conditions, we observe significant increases in accelerated charge compared to previous experiments with near-infrared (\lambda=800 nm) pulses

Warehouse Commodity Classification from Fundamental Principles

Abstract In warehouse storage applications, it is important to classify the burning behavior of commodities and rank them according to their material flammability for early fire detection and suppression operations. In this study, a preliminary approach towards commodity classification is presented that models the early stage of large-scale warehouse fires by decoupling the problem into separate processes of heat and mass transfer. Two existing nondimensional parameters are used to represent the physical phenomena at the large-scale: a mass transfer number that directly incorporates the material properties of a fuel, and the soot yield of the fuel that controls the radiation observed in the large-scale. To facilitate modeling, a mass transfer number (or B-number) was experimentally obtained using mass-loss (burning rate) measurements from bench-scale tests, following from a procedure that was developed in Part I of this paper. Two fuels are considered: corrugated cardboard and polystyrene. Corrugated cardboard provides a source of flaming combustion in a warehouse and is usually the first item to ignite and sustain flame spread. Polystyrene is typically used as the most hazardous product in large-scale fire testing. The nondimensional mass transfer number was then used to model in-rack flame heights on 6.1 − 9.1 m (20 − 30 ft) stacks of 'C' flute corrugated cardboard * Corresponding author Email address: [email protected] (K.J. Overholt) Preprint submitted to Fire Safety Journal January 11, 2011 boxes on rack-storage during the initial period of flame spread (involving flame spread over the corrugated cardboard face only). Good agreement was observed between the model and large-scale experiments during the initial stages of fire growth, and a comparison to previous correlations for in-rack flame heights is included

Exploring the ecology of deep-sea hydrothermal vents in a metacommunity framework

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Frontiers in Marine Science 5 (2018): 49, doi:10.3389/fmars.2018.00049.Species inhabiting deep-sea hydrothermal vents are strongly influenced by the geological setting, as it provides the chemical-rich fluids supporting the food web, creates the patchwork of seafloor habitat, and generates catastrophic disturbances that can eradicate entire communities. The patches of vent habitat host a network of communities (a metacommunity) connected by dispersal of planktonic larvae. The dynamics of the metacommunity are influenced not only by birth rates, death rates and interactions of populations at the local site, but also by regional influences on dispersal from different sites. The connections to other communities provide a mechanism for dynamics at a local site to affect features of the regional biota. In this paper, we explore the challenges and potential benefits of applying metacommunity theory to vent communities, with a particular focus on effects of disturbance. We synthesize field observations to inform models and identify data gaps that need to be addressed to answer key questions including: (1) what is the influence of the magnitude and rate of disturbance on ecological attributes, such as time to extinction or resilience in a metacommunity; (2) what interactions between local and regional processes control species diversity, and (3) which communities are “hot spots” of key ecological significance. We conclude by assessing our ability to evaluate resilience of vent metacommunities to human disturbance (e.g., deep-sea mining). Although the resilience of a few highly disturbed vent systems in the eastern Pacific has been quantified, these values cannot be generalized to remote locales in the western Pacific or mid Atlantic where disturbance rates are different and information on local controls is missing.LM was supported by NSF OCE 1356738 and DEB 1558904. SB was supported by the NSF DEB 1558904 and the Investment in Science Fund at Woods Hole Oceanographic Institution. MB was supported by the Austrian Science Fund grants P20190-B17 and P16774-B03. LL was supported by NSF OCE 1634172 and the JM Kaplan Fund. MN was supported by NSF DEB 1558904. Y-JW was supported by a Korean Institute of Ocean Science and Technology (KIOST) grant PM60210

Diversity of Meiofauna from the 9°50′N East Pacific Rise across a Gradient of Hydrothermal Fluid Emissions

Background: We studied the meiofauna community at deep-sea hydrothermal vents along a gradient of vent fluid emissions in the axial summit trought (AST) of the East Pacific Rise 9 degrees 50'N region. The gradient ranged from extreme high temperatures, high sulfide concentrations, and low pH at sulfide chimneys to ambient deep-sea water conditions on bare basalt. We explore meiofauna diversity and abundance, and discuss its possible underlying ecological and evolutionary processes. Methodology/Principal Findings: After sampling in five physico-chemically different habitats, the meiofauna was sorted, counted and classified. Abundances were low at all sites. A total of 52 species were identified at vent habitats. The vent community was dominated by hard substrate generalists that also lived on bare basalt at ambient deep-sea temperature in the axial summit trough (AST generalists). Some vent species were restricted to a specific vent habitat (vent specialists), but others occurred over a wide range of physico-chemical conditions (vent generalists). Additionally, 35 species were only found on cold bare basalt (basalt specialists). At vent sites, species richness and diversity clearly increased with decreasing influence of vent fluid emissions from extreme flow sulfide chimney (no fauna), high flow pompei worm (S: 4-7, H-loge': 0.11-0.45), vigorous flow tubeworm (S: 8-23; H-loge': 0.44-2.00) to low flow mussel habitats (S: 28-31; H-loge': 2.34-2.60). Conclusions/Significance: Our data suggest that with increasing temperature and toxic hydrogen sulfide concentrations and increasing amplitude of variation of these factors, fewer species are able to cope with these extreme conditions. This results in less diverse communities in more extreme habitats. The finding of many species being present at sites with and without vent fluid emissions points to a non endemic deep-sea hydrothermal vent meiofaunal community. This is in contrast to a mostly endemic macrofauna but similar to what is known for meiofauna from shallow-water vents

Resilience of benthic deep-sea fauna to mining activities

With increasing demand for mineral resources, extraction of polymetallic sulphides at hydrothermal vents, cobalt-rich ferromanganese crusts at seamounts, and polymetallic nodules on abyssal plains may be imminent. Here, we shortly introduce ecosystem characteristics of mining areas, report on recent mining developments, and identify potential stress and disturbances created by mining. We analyze species' potential resistance to future mining and perform meta-analyses on population density and diversity recovery after disturbances most similar to mining: volcanic eruptions at vents, fisheries on seamounts, and experiments that mimic nodule mining on abyssal plains. We report wide variation in recovery rates among taxa, size, and mobility of fauna. While densities and diversities of some taxa can recover to or even exceed pre-disturbance levels, community composition remains affected after decades. The loss of hard substrata or alteration of substrata composition may cause substantial community shifts that persist over geological timescales at mined sites. (C) 2017 Elsevier Ltd. All rights reserved.European Union Seventh Framework Programme (FP7) under the MIDAS project; FCT [IF/00029/2014/CP1230/CT0002, SFRH/ BPD/110278/2015]; Spanish RTD project NUREIEV [CTM2013-44598-R]; Ministry of Economy and Competitiveness [SGR 1068]; Generalitat de Catalunya autonomous government; European Union Horizon research and innovation programme [689518]; Fundacao para a Ciencia e a Tecnologia [UID/MAR/04292/2013]; German Ministry of Research (BMBF) [03F0707A-G]; Program Investigador FCT [IF/01194/2013/CP1199/CT0002]info:eu-repo/semantics/publishedVersio

Österreichisches Projekt Grundlagen zur Züchtung, Vermehrung und Sorten-/Saatgutprüfung für den Biolandbau: Ergebnisübersicht

In the Austrian research project “Basic principles for breeding, multiplication and variety testing for organic agriculture” (from 2004 until 2008) novel methods for the assessment of the suitability of seed and cultivars for organic farming were developed and evaluated by an interdisciplinary co-operation of researchers, breeders and variety testers. Organic farming requires specific combinations of crop plant characters, especially seed health and resistance against seed-borne diseases. Another crucial feature is the competitive ability against weeds. Early development was found to significantly increase the competitiveness of different crop plants. Genotypic variation in characters necessary for an efficient utilisation of below-ground resources was also investigated, e.g. interrelations between root development and drought stress tolerance and between mycorrhiza formation and nutrient use efficiency. Based on the results obtained in various cultivar trials, it can be concluded that genotypes suitable for organic growing conditions may be pre-selected from early breeding material of conventional breeding programmes. The selected breeding material must subsequently be rigorously tested on organically managed fields starting from the first yield trials at the latest. The project results were communicated to farmers and advisors during field days and excursions. They will be applied in the breeding of new cultivars

Mining deep-ocean mineral deposits: what are the ecological risks?

A key question for the future management of the oceans is whether the mineral deposits that exist on the seafloor of the deep ocean can be extracted without significant adverse effects to the environment. The potential impacts of mining are wide-ranging and will vary depending on the type of metal-rich mineral deposit being mined. There is, currently, a significant lack of information about deep-ocean ecosystems and about potential mining technologies: thus, there could be many unforeseen impacts. Here, we discuss the potential ecological impacts of deep-ocean mining and identify the key knowledge gaps to be addressed. Baseline studies must be undertaken, as well as regular monitoring of a mine area, before, during, and after mineral extraction.The attached document is the author’s submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it