1,722,031 research outputs found
Pseudevoplitus vittatus Grazia, Becker & Thomas 1994
No full textPseudevoplitus vittatus Grazia, Becker & Thomas Grazia et al., 1994 Paratype (1) (NDM) ♀— Brazil, Amazonas, Manicore, margem do Rio Madeira, VIII- 1941, Parko coll. Deposited MCNZ.Published as part of Ruschel, Tatiana Petersen, Guidoti, Marcus & Barcellos, Aline, 2013, The Hemiptera type-material housed in the " Museu de Ciências Naturais, Fundação Zoobotânica do Rio Grande do Sul " of Porto Alegre, Brazil, pp. 539-564 in Zootaxa 3716 (4) on page 556, DOI: 10.11646/zootaxa.3716.4.3, http://zenodo.org/record/21937
Pseudevoplitus costalimai Grazia, Becker & Thomas 1994
No full textPseudevoplitus costalimai Grazia, Becker & Thomas Grazia et al., 1994 Holotype (NDM) ♂—Brazil, Minas Gerais, Laisance, VIII-1934, E. Dias coll., em ninho de ave, ex. coll. Costa Lima. Deposited MCNZ.Published as part of Ruschel, Tatiana Petersen, Guidoti, Marcus & Barcellos, Aline, 2013, The Hemiptera type-material housed in the " Museu de Ciências Naturais, Fundação Zoobotânica do Rio Grande do Sul " of Porto Alegre, Brazil, pp. 539-564 in Zootaxa 3716 (4) on page 555, DOI: 10.11646/zootaxa.3716.4.3, http://zenodo.org/record/21937
Pseudevoplitus vittatus Grazia, Becker & Thomas 1994
No full textPseudevoplitus vittatus Grazia, Becker & Thomas, 1994 Distribution. A—Amazonas and Rondônia. C—Ecuador (Grazia et al. 1994, 2016).Published as part of Silva, Valeria Juliete Da, Santos, Cleverson Rannieri Meira Dos & Fernandes, Jose Antonio Marin, 2018, Stink bugs (Hemiptera: Pentatomidae) from Brazilian Amazon: checklist and new records, pp. 401-455 in Zootaxa 4425 (3) on page 444, DOI: 10.11646/zootaxa.4425.3.1, http://zenodo.org/record/126751
Explaining Rarity of the Dry Grassland Perennial Astragalus exscapus
Full text linkIn Central Europe several plant species of dry grasslands are particularly rare. Here I investigate whether habitat requirements, reproduction, and dispersal potential can contribute to the rarity of Astragalus exscapus (Fabaceae) growing in dry grassland habitats in dry regions of Europe. In addition, I question whether historic events might have contributed to the present-day rarity of A. exscapus. To assess habitat requirements of A. exscapus, vegetation composition and soil characteristics were studied in 37 populations in central Germany. Production and dispersal potential of seeds were investigated in 10 populations, and germination and recruitment were assessed in experimental plots in three populations. Vegetation of the habitats included most dry grassland community types occurring in the central German dry region indicating a broad ecological niche of the species within dry subcontinental grasslands. Soil characteristics of the habitats also spanned a wide range. Seed production was moderate. 98% of the seeds sown in the laboratory germinated whereas under natural conditions 20% of the seeds developed seedlings. Half of these seedlings survived for one year but only 4.5% for two years. 90% of the seeds were dispersed less than 50 cm distance indicating a low dispersal potential. I conclude that A. exscapus is mainly limited in dispersal but recruitment limitation might also be important in explaining its rarity. Furthermore, former climate change and postglacial reforestation of the area very likely contribute to the rarity of A. exscapus
Plant diversity differs between young and old mesic meadows in a central European low mountain region
No full textEffects of habitat age on species diversity are an important issue in plant conservation. However, effects of habitat age on mesic meadows are poorly investigated. Here we compare plant species richness between old mesic meadows (> 150 years) and young mesic meadows (40-60 years) in a low mountain region (Thuringian Forest, Germany). Species richness and species traits were determined in 20 old and 20 young mountain meadows (alliances Polygono-Trisetion, Violion caninae) which were defined using historical maps and compared using species indicator analysis and ANOVA. Additionally we quantified changes in the extent of the area of young and old meadows using a Geographical Information System. Species richness of vascular plants on 20 m(2) plots was significantly higher in old than in young meadows, while evenness did not differ between young and old meadows. Endangered plant species were restricted to old meadows. which also contained a higher proportion of habitat specialists. The terminal velocity index of seeds was lower and seed weight was higher in old meadows, indicating a lower importance of wind dispersal in old meadows. This was also indicated by a higher proportion of species with seeds adapted to wind dispersal in young meadows. In old meadows there was a higher proportion of species with seeds adapted to ant dispersal and a lower proportion of species with seeds adapted to animal dispersal. In a representative sub-area of the study region, the total area of meadows has increased by 88% during the 20th century due to transformation of arable fields into meadows, while the area of old meadows declined by 36% during the same time due to abandonment and afforestation. We conclude that the age of the habitat is highly important in order to maintain plant diversity of mesic meadows. Therefore, higher priority should be given to old meadows. (C) 2008 Elsevier B.V. All rights reserved.Evangelisches Studienwerk Villigs
Vegetation response to high concentrations of heavy metals in the Harz Mountains, Germany
No full textHeavy metal content is assumed to be the most important edaphic factor determining vegetation composition on contaminated soil. We compared the relationships between vegetation composition and heavy metal content at 23 mining sites in the Hart Mountains in Germany with those of other soil environmental factors. 120 releves were assigned to the Armerierum halleri which was subdivided into three subassociations, A. cladonietosum, A. typicum and A. achilletosum. Within each of the latter subassociations a Typical variant and a Cardaminopsis halleri variant were classified. The first axis of a DCA was positively correlated with Ellenberg's indicator values for soil reaction, nitrogen and moisture, and the concentration of calcium, and negatively with the concentration of copper and the proportion of stones, indicating that these variables were most important for vegetation differentiation. Soil concentrations of lead and exchangeable zinc did not differ significantly between the communities, while concentrations of copper and water-soluble zinc were highest in the A. cladonietosum and lowest in the A. achilletosum. Ellenberg's indicator values for nitrogen indicate poorest nutrient conditions in the A. cladonietosum where soil depth was especially low and richest conditions in the A. achilletosum where soil depth was higher. Logistic regression showed that the presence of the metallicolous Minuartia verna subsp. hercymica increased with the concentration of soluble zinc in the soil, while the presence of Armeria maritima subsp. halleri and Cardaminopsis halleri decreased with increasing concentration of copper. Armeria was furthermore strongly negatively affected by altitude, while Cardaminopsis was positively affected by soil depth and moisture. Silene vulgaris var. humilis was neither influenced by heavy metals nor by other environmental factors. A comparison of the recent number of slag heaps with those listed in a 75 year old study demonstrates a strong decline of these habitats and their specific vegetation due to both human destruction and natural succession. - We conclude that heavy metals are by far not the only factor controlling vegetation on metalliferous soils. At the mining sites investigated vegetation is also strongly controlled by low soil fertility
37 years of permanent plot research within a calcareous beech forest – a time series 1980–2001–2016
No full textIm Rahmen eines Ökosystem-Forschungsprojektes in der Nähe von Göttingen wurden 1980 auf fest markierten Flächen eines artenreichen Kalkbuchenwaldes (Hordelymo-Fagetum lathyretosum) 41 Vegetationsaufnahmen gemacht, in den Jahren 2001 und 2016 wiederholt und nun als Zeitreihe verglichen. In allen Schichten wurden signifikante Veränderungen von Struktur und Artenzusammensetzung festgestellt. Nach hohen Deckungsgraden einzelner krautiger Arten wurden 1980 verschiedene Dominanztypen (DT) unterschieden. Die unterschiedliche Zuordnung der 41 Aufnahmen im Zeitverlauf zu diesen DT wies bereits auf strukturelle Veränderungen hin. Vor allem der zunächst bestimmende Mercurialis perennis-DT hat sich zum Allium ursinum- oder Anemone nemorosa-DT hin verschoben (Tab. 1–2). Im Gesamtvergleich (Tab. 3–4) zeigen sich weitere strukturelle und floristische Veränderungen. Die von Fagus sylvatica beherrschte Baumschicht entwickelte ein dichteres Kronendach. Die Einzäunung der gesamten Untersuchungsfläche leitete wegen Ausschluss des Wildverbisses die Ausbildung einer Strauchschicht, vorwiegend aus Jungbäumen ein. Die statistisch ausgewerteten Veränderungen in der Krautschicht ergaben Artengruppen unterschiedlicher Dynamik: 15 Gewinner, 20 Verlierer und 18 konstante Arten. Ein Literaturvergleich zeigt teilweise sehr ähnliche Ergebnisse (Tab. 5). Die Gesamtartenzahl aller Flächen nahm von 1980 bis 2016 von 63 auf 58 ab. Funktionelle Eigenschaften (Lebensformen, Blattausdauer; Abb. 2–3) zeigen nur geringe Veränderungen. Fast alle Krautigen gehören zu Artengruppen mit starker Waldbindung (Abb. 3). Die Auswertung ökologischer Zeigerwerte (Abb. 4) lässt die Entwicklung zu einem stärker schattigen und luftfeuchten Mikroklima vermuten. Eine Gradientenanalyse (NMDS) zeigt ebenfalls deutliche zeitliche Veränderungen (Abb. 5). Als Hauptursache der Vegetationsveränderungen wird die langzeitige Forstgeschichte angenommen, d. h. der Übergang von extensiver Mittelwald- zu Hochwaldwirtschaft innerhalb von etwa 100 Jahren. Der Klimawandel ist derzeit vor allem in der Verfrühung und Verlängerung der Frühlings-Phänophasen erkennbar und hat u. a. die Frühlingsgeophyten gefördert. Die oft beschriebenen Eutrophierungswirkungen durch atmosphärische N-Einträge scheinen hier hingegen keine größere Rolle zu spielen. Trotz sich wandelnder Umweltbedingungen in fast 40 Jahren hat sich die grundlegende Struktur und Artenzusammensetzung des Bestandes bisher kaum verändert.In 1980, within an ecosystem research project nearby Göttingen 41 vegetation relevés have been made on permanently marked plots within a calcareous beech forest (Hordelymo-Fagetum lathyretosum). These relevés have been repeated in 2001 and 2016 and were now analysed as a time series. In all vegetation layers significant changes could be found. In 1980 different dominance types (DT) were defined by high coverage of single plant species of the herb layer. The different allocation of the relevés to these DT over time indicated structural changes. Especially the 1980 prevalent Mercurialis perennis-DT shifted to the Allium ursinum- or Anemone nemorosa-DT (Table 1–2). The total comparison (Table 3–4) showes further structural and floristic changes. The tree layer, dominated by Fagus sylvatica, developed a denser canopy. Fencing of the total research area initiated the establishment of a shrub layer, mainly consisting of young trees. The statistically evaluated changes in the herb layer resulted in species groups of different dynamics: 15 winners, 20 losers and 18 constant species. Comparisons with literature data show partly similar results (Table 5). The total species number of all relevés decreased from 63 to 58. Functional traits (life form, leave longevity; Fig. 2–3) changed only slightly. Almost all herbaceous plants have a strong forest affinity (Fig. 3). The evaluation of ecological indicator values (Fig. 4) suggests the development of a more shady and humid microclimate. An ordination (NMDS; Fig. 5) also showes a clear floristic change over time. As the main driver for vegetation changes the forest history is considered, i.e. the change from a coppice-with-standards to high forest management since about 100 years. Climate change is especially recognizable by earlier beginning and longer lasting of spring phenophases, among others promoting spring geophytes. The often described eutrophication by atmospheric nitrogen input, however, seems to be not very important. Despite of changing ecological conditions within almost 40 years no basic structural-floristic changes can be observed
Replication data for REEF3D Sommerfeld benchmarking and Sirevåg harbor application case
No full textThe data set contains the necessary simulation files and key output files for the results shown in the related publication. Specifically, the dataset should allow the reproduction of the REEF3D::NHFLOW and SWAN simulations. Certain result deviations may occur due to different software versions and irregular wave seeds
- …
