Browsing by Subject "vegetation dynamics"

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    How plot shape and spatial arrangement affect plant species richness counts: implications for sampling design and rarefaction analyses
    (Wiley-Blackwell, 2016) Güler B.; Jentsch A.; Apostolova I.; Bartha S.; Bloor J.M.G.; Campetella G.; Canullo R.; Házi J.; Kreyling J.; Pottier J.; Szabó G.; Terziyska T.; Uğurlu E.; Wellstein C.; Zimmermann Z.; Dengler J.
    Questions: How does the spatial configuration of sampling units influence recorded plant species richness values at small spatial scales? What are the consequences of these findings for sampling methodology and rarefaction analyses?. Location: Six semi-natural grasslands in Western Eurasia (France, Germany, Bulgaria, Hungary, Italy, Turkey). Methods: In each site we established six blocks of 40 cm × 280 cm, subdivided into 5 cm × 5 cm micro-quadrats, on which we recorded vascular plant species presence with the rooted (all sites) and shoot (four sites) presence method. Data of these micro-quadrats were then combined to achieve larger sampling units of 0.01, 0.04 and 0.16 m² grain size with six different spatial configurations (square, 4:1 rectangle, 16:1 rectangle, three variants of discontiguous randomly placed micro-quadrats). The effect of the spatial configurations on species richness was quantified as relative richness compared to the mean richness of the square of the same surface area. Results: Square sampling units had significantly lower species richness than other spatial configurations in all countries. For 4:1 and 16:1 rectangles, the increase of rooted richness was on average about 2% and 8%, respectively. In contrast, the average richness increase for discontiguous configurations was 7%, 17% and 40%. In general, increases were higher with shoot presence than with rooted presence. Overall, the patterns of richness increase were highly consistent across six countries, three grain sizes and two recording methods. Conclusions: Our findings suggest that the shape of sampling units has negligible effects on species richness values when the length–width ratio is up to 4:1, and the effects remain small even for more elongated contiguous configurations. In contrast, results from discontiguous sampling units are not directly comparable with those of contiguous sampling units, and are strongly confounded by spatial extent. This is particularly problematic for rarefaction studies where spatial extent is often not controlled for. We suggest that the concept of effective area is a useful tool to report effects of spatial configuration on richness values, and introduce species–extent relationships (SERs) to describe richness increases of different spatial configurations of sampling units. © 2016 International Association for Vegetation Science
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    sPlot – A new tool for global vegetation analyses
    (Wiley-Blackwell, 2019) Bruelheide H.; Dengler J.; Jiménez-Alfaro B.; Purschke O.; Hennekens S.M.; Chytrý M.; Pillar V.D.; Jansen F.; Kattge J.; Sandel B.; Aubin I.; Biurrun I.; Field R.; Haider S.; Jandt U.; Lenoir J.; Peet R.K.; Peyre G.; Sabatini F.M.; Schmidt M.; Schrodt F.; Winter M.; Aćić S.; Agrillo E.; Alvarez M.; Ambarlı D.; Angelini P.; Apostolova I.; Arfin Khan M.A.S.; Arnst E.; Attorre F.; Baraloto C.; Beckmann M.; Berg C.; Bergeron Y.; Bergmeier E.; Bjorkman A.D.; Bondareva V.; Borchardt P.; Botta-Dukát Z.; Boyle B.; Breen A.; Brisse H.; Byun C.; Cabido M.R.; Casella L.; Cayuela L.; Černý T.; Chepinoga V.; Csiky J.; Curran M.; Ćušterevska R.; Dajić Stevanović Z.; De Bie E.; de Ruffray P.; De Sanctis M.; Dimopoulos P.; Dressler S.; Ejrnæs R.; El-Sheikh M.A.E.-R.M.; Enquist B.; Ewald J.; Fagúndez J.; Finckh M.; Font X.; Forey E.; Fotiadis G.; García-Mijangos I.; de Gasper A.L.; Golub V.; Gutierrez A.G.; Hatim M.Z.; He T.; Higuchi P.; Holubová D.; Hölzel N.; Homeier J.; Indreica A.; Işık Gürsoy D.; Jansen S.; Janssen J.; Jedrzejek B.; Jiroušek M.; Jürgens N.; Kącki Z.; Kavgacı A.; Kearsley E.; Kessler M.; Knollová I.; Kolomiychuk V.; Korolyuk A.; Kozhevnikova M.; Kozub Ł.; Krstonošić D.; Kühl H.; Kühn I.; Kuzemko A.; Küzmič F.; Landucci F.; Lee M.T.; Levesley A.; Li C.-F.; Liu H.; Lopez-Gonzalez G.; Lysenko T.; Macanović A.; Mahdavi P.; Manning P.; Marcenò C.; Martynenko V.; Mencuccini M.; Minden V.; Moeslund J.E.; Moretti M.; Müller J.V.; Munzinger J.; Niinemets Ü.; Nobis M.; Noroozi J.; Nowak A.; Onyshchenko V.; Overbeck G.E.; Ozinga W.A.; Pauchard A.; Pedashenko H.; Peñuelas J.; Pérez-Haase A.; Peterka T.; Petřík P.; Phillips O.L.; Prokhorov V.; Rašomavičius V.; Revermann R.; Rodwell J.; Ruprecht E.; Rūsiņa S.; Samimi C.; Schaminée J.H.J.; Schmiedel U.; Šibík J.; Šilc U.; Škvorc Ž.; Smyth A.; Sop T.; Sopotlieva D.; Sparrow B.; Stančić Z.; Svenning J.-C.; Swacha G.; Tang Z.; Tsiripidis I.; Turtureanu P.D.; Uğurlu E.; Uogintas D.; Valachovič M.; Vanselow K.A.; Vashenyak Y.; Vassilev K.; Vélez-Martin E.; Venanzoni R.; Vibrans A.C.; Violle C.; Virtanen R.; von Wehrden H.; Wagner V.; Walker D.A.; Wana D.; Weiher E.; Wesche K.; Whitfeld T.; Willner W.; Wiser S.; Wohlgemuth T.; Yamalov S.; Zizka G.; Zverev A.
    Aims: Vegetation-plot records provide information on the presence and cover or abundance of plants co-occurring in the same community. Vegetation-plot data are spread across research groups, environmental agencies and biodiversity research centers and, thus, are rarely accessible at continental or global scales. Here we present the sPlot database, which collates vegetation plots worldwide to allow for the exploration of global patterns in taxonomic, functional and phylogenetic diversity at the plant community level. Results: sPlot version 2.1 contains records from 1,121,244 vegetation plots, which comprise 23,586,216 records of plant species and their relative cover or abundance in plots collected worldwide between 1885 and 2015. We complemented the information for each plot by retrieving climate and soil conditions and the biogeographic context (e.g., biomes) from external sources, and by calculating community-weighted means and variances of traits using gap-filled data from the global plant trait database TRY. Moreover, we created a phylogenetic tree for 50,167 out of the 54,519 species identified in the plots. We present the first maps of global patterns of community richness and community-weighted means of key traits. Conclusions: The availability of vegetation plot data in sPlot offers new avenues for vegetation analysis at the global scale. © 2019 International Association for Vegetation Science