Modern pollen-vegetation relationships along a steep temperature gradient in the Tropical Andes of Ecuador

2019 ◽  
Vol 92 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Kimberley Hagemans ◽  
Claudia-Dana Tóth ◽  
Manuela Ormaza ◽  
William D. Gosling ◽  
Dunia H. Urrego ◽  
...  
Keyword(s):  
Temperature Gradient ◽  
Vascular Plant ◽  
Montane Forest ◽  
Sediment Surface ◽  
Tropical Andes ◽  
Modern Pollen ◽  
Surface Samples ◽  
Steep Temperature Gradient ◽  
Pollen Rain ◽  
Moss Polsters

AbstractThe characterization of modern pollen rain assemblages along environmental gradients is an essential prerequisite for reliable interpretations of fossil pollen records. In this study, we identify pollen-vegetation relationships using modern pollen rain assemblages in moss polsters (n = 13) and lake sediment surface samples (n = 11) along a steep temperature gradient of 7°C (3100–4200 m above sea level) on the western Andean Cordillera, Ecuador. The pollen rain is correlated to vascular plant abundance data recorded in vegetation relevées (n = 13). Results show that pollen spectra from both moss polsters and sediment surface samples reflect changes in species composition along the temperature gradient, despite overrepresentation of upper montane forest taxa in the latter. Estimated pollen transport distance for a lake (Laguna Llaviucu) situated in a steep upper montane forest valley is 1–2 km, while a lake (Laguna Pallcacocha) in the páramo captures pollen input from a distance of up to 10–40 km. Weinmannia spp., Podocarpus spp., and Hedyosmum sp. are indicators of local upper montane forest vegetation, while Phlegmariurus spp. and Plantago spp. are indicators for local páramo vegetation.

MODERN POLLEN RAIN STUDIES IN EASTERN ONTARIO

1963 ◽  
Vol 41 (2) ◽  
pp. 243-252 ◽  
Author(s):  
James E. King ◽  
Ronald O. Kapp
Keyword(s):  
United States ◽  
Long Range ◽  
Southwestern United States ◽  
Pollen Trap ◽  
Modern Pollen ◽  
Pollen Rain ◽  
Moss Polsters ◽  
Eastern Ontario

Moss polsters were collected at 15 sites between Toronto and Lake Timagami, Ontario, and at 4 localities in the Lake Timagami area for the purpose of determining the regional pollen rain and its local variations. Pollen percentages of Acer, Quercus, Ambrosia, Chenopodiaceae, Compositae, and Gramineae decrease northward and Picea, Pinus, and Betula increase at the more northerly sites. From the three most northern sites a regional pollen rain was calculated by averaging the percentages from nine pollen spectra. In this area the regional pollen rain is dominated by Picea (15%), Pinus (38%), and Betula (22%). At one site a grain of Ephedra was recovered, apparently carried in by long range drift. The nearest place that it grows naturally is in the southwestern United States. Various pollen trap types were investigated and it was found that all types of moss polsters and some types of decaying stumps (depending on their moisture-holding capacity) were effective in preserving the modern pollen rain.

scholarly journals Phytosociological and ecological discrimination of Mediterranean cypress ('Cupressus sempervirens') communities in Crete (Greece) by means of pollen analysis

2019 ◽  
Vol 40 (2) ◽  
pp. 145-163 ◽  
Author(s):  
José Antonio López-Sáez ◽  
Arthur Glais ◽  
Ioannis Tsiripidis ◽  
Spyros Tsiftsis ◽  
Daniel Sánchez-Mata ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Hierarchical Cluster ◽  
Cupressus Sempervirens ◽  
New Associations ◽  
Modern Pollen ◽  
Surface Samples ◽  
Aegean Islands ◽  
Temperature Regimes ◽  
Pollen Content ◽  
Pollen Rain

Sixty modern surface samples collected from mosses in different cypress forest communities (Cupressus sempervirens L.) on the island of Crete (Greece) were analysed for their pollen content. The samples were taken from six different cypress phytosociological associations between 23 and 1600 m asl, and fall within distinct rainfall and temperature regimes. The aims of this paper are to provide new data on the modern pollen rain from the Aegean islands, and to perform these data using multivariate statistics (hierarchical cluster analysis and canonical correspondence analysis) and pollen percentages. The discrimination of pollen assemblages corresponds to a large extent to the floristic differentiation of Cupressus sempervirens forest vegetation and indicates the existence of three new associations.

scholarly journals Pollen-based temperature and precipitation inferences for the montane forest of Mt. Kilimanjaro during the last Glacial and the Holocene

2014 ◽  
Vol 10 (1) ◽  
pp. 195-234 ◽  
Author(s):  
L. Schüler ◽  
A. Hemp ◽  
H. Behling
Keyword(s):  
East Africa ◽  
Transfer Functions ◽  
Montane Forest ◽  
Weighted Averaging ◽  
Pollen Record ◽  
Climate Variables ◽  
The Holocene ◽  
Modern Pollen ◽  
Temperature And Precipitation ◽  
Pollen Rain

Abstract. The relationship between modern pollen-rain taxa and measured climate variables was explored along the elevational gradient of the southern slope of Mt. Kilimanjaro, Tanzania. Pollen assemblages in 28 pollen traps positioned on 14 montane forest vegetation plots were identified and their relationship with climate variables was examined using multivariate statistical methods. Canonical correspondence analysis revealed that the mean annual temperature, mean annual precipitation and minimum temperature each account for significant fractions of the variation in pollen taxa. A training set of 107 modern pollen taxa was used to derive temperature and precipitation transfer functions based on pollen subsets using weighted-averaging-partial-least-squares (WA-PLS) techniques. The transfer functions were then applied to a fossil pollen record from the montane forest of Mt. Kilimanjaro and the climate parameter estimates for the Late Glacial and the Holocene on Mt. Kilimanjaro were inferred. Our results present the first quantitatively reconstructed temperature and precipitation estimates for Mt Kilimanjaro and give highly interesting insights into the past 45 000 yr of climate dynamics in tropical East Africa. The climate reconstructions are consistent with the interpretation of pollen data in terms of vegetation and climate history of afro-montane forest in East Africa. Minimum temperatures above the frostline as well as increased precipitation turn out to be crucial for the development and expansion of montane forest during the Holocene. In contrast, consistently low minimum temperatures as well as about 25% drier climate conditions prevailed during the pre LGM, which kept the montane vegetation composition in a stable state. In prospective studies, the quantitative climate reconstruction will be improved by additional modern pollen rain data, especially from lower elevations with submontane dry forests and colline savanna vegetation in order to extend the reference climate gradient.

Pollen Taphonomy in a Canyon Stream

1987 ◽  
Vol 28 (3) ◽  
pp. 393-406 ◽  
Author(s):  
Patricia L. Fall
Keyword(s):  
Surface Soil ◽  
Pollen Grains ◽  
Close Correlation ◽  
Soil Samples ◽  
Alluvial Deposits ◽  
Modern Pollen ◽  
Pollen Types ◽  
Pollen Rain ◽  
Arid Steppe ◽  
Turbulent Water

AbstractSurface soil samples from the forested Chuska Mountains to the arid steppe of the Chinle Valley, Northeastern Arizona, show close correlation between modern pollen rain and vegetation. In contrast, modern alluvium is dominated by Pinus pollen throughout the canyon; it reflects neither the surrounding floodplain nor plateau vegetation. Pollen in surface soils is deposited by wind; pollen grains in alluvium are deposited by a stream as sedimentary particles. Clay-size particles correlate significantly with Pinus, Quercus, and Populus pollen. These pollen types settle, as clay does, in slack water. Chenopodiaceae-Amaranthus, Artemisia, other Tubuliflorae, and indeterminate pollen types correlate with sand-size particles, and are deposited by more turbulent water. Fluctuating pollen frequencies in alluvial deposits are related to sedimentology and do not reflect the local or regional vegetation where the sediments were deposited. Alluvial pollen is unreliable for reconstruction of paleoenvironments.

scholarly journals Flora vascular da Serra da Pedra Branca, Caldas, Minas Gerais e relações florísticas com áreas de altitude da Região Sudeste do Brasil

2013 ◽  
Vol 13 (4) ◽  
pp. 201-224 ◽  
Author(s):  
Munike Gonçalves de Rezende ◽  
Ricardo Cunha Loyola Elias ◽  
Fátima Regina Gonçalves Salimena ◽  
Luiz Menini Neto
Keyword(s):  
New Records ◽  
Vascular Plant ◽  
Montane Forest ◽  
Minas Gerais ◽  
The State ◽  
Mountain Range ◽  
Floristic Similarity ◽  
Floristic Survey ◽  
Ombrophilous Forest ◽  
Southeastern Region

Serra da Pedra Branca (SPB) is a mountain range located in the Southwestern portion of the state Minas Gerais, in the municipality of Caldas (21°58′-21°55′S, 46°24′-46°22′W). It is a striking feature in the landscape, between 1100 and 1780 m.s.m., in a region that is part of the Atlantic Forest Domain and is considered as a priority area for conservation of the flora in Minas Gerais state. The vegetation is composed by a mosaic of “campo de altitude” (which occupy the greatest extension in the area), Seasonal Semidecidual Montane Forest, Dense Ombrophilous High-Montane Forest and Mixed Ombrophilous Forest. The aims of this study was the elaboration of a floristic survey of SPB added to the specimens collected by Anders Fredrik Regnell in the nineteenth century in Caldas and to analyze its floristic similarity with altitude areas of the Southeastern Region of Brazil. There were recorded 502 vascular plant species, distributed in 274 genera and 100 families. The majority of recorded species present herbaceous habit, terricolous, saxicolous and/or rupicolous (representing around 58% of recorded species), predominantly occurring in the “campo de altitude” (ca. 46%). The richest families were Polypodiaceae (20 spp.) and Dryopteridaceae (10 spp.) among the ferns, and Orchidaceae (56 spp.), Asteraceae (27 spp.) and Fabaceae (26 spp.) among the angiosperms. Just one species of gymnosperm was recorded, Araucaria angustifolia (Bertol.) Kuntze (Araucariaceae). Five new records were made for the Minas Gerais flora, 13 species are cited as threatened with extinction in the state and at least six are endemic to SPB. Amongst 127 species collected in XIX century in the region, only 29 collected again, while 375 new records were made for SPB. The analysis of floristic similarity performed between the flora of SPB and other altitude areas of Southeastern Region revealed isolation of SPB in relation to other areas, highlighting its floristic peculiarity, which can probably be explained by its location in a distinct hydrographic basin. The vegetation of the SPB must be considered as endangered since the presence of endemic species and/or threatened species, associated with local environmental conditions suffering accelerated rate of destruction, highlight the need for urgent actions to preserve local biodiversity.

scholarly journals Relación lluvia de polen-vetación en selvas de Quintana Roo

2017 ◽  
pp. 31 ◽  
Author(s):  
Gerald A. Islebe ◽  
Rogel Villanueva-Gutiérrez ◽  
Odilón Sánchez-Sánchez
Keyword(s):  
Zea Mays ◽  
Quintana Roo ◽  
Vegetation Types ◽  
Pollen Data ◽  
Indicator Taxa ◽  
Modern Pollen ◽  
Pollen Content ◽  
Ordination Techniques ◽  
Ordination Analysis ◽  
Pollen Rain

Modern pollen rain was studied along a 450 km long transect between Cancun-La Unión (Belizean border). Ten moss samples were collected in different vegetation types and analyzed for pollen content. The data were analyzed with classification (TWINSPAN), ordination analysis (DCA) and different association indices. Classification and ordination techniques allowed us to recognize three different pollen signals from semievergreen forest (with Maclura, Apocynaceae, Moraceae, Sapotaceae, Araceae, Cecropia, Celtis, Eugenia and Bursera), acahual (with con Coccoloba, Metopium, Anacardiaceae, Urticales, Melothria, Croton, Palmae) and disturbed vegetation (with Zea mays, Mimosa and Asteraceae ) . The degree of over-representation and underrepresentation of the pollen data with respect to the modem vegetation was established, being under-represented mostly entomophilous species. We can conclude that the actual pollen signal can be used for calibrating paleosignals, if clear groups of indicator taxa can be established.

Sign in / Sign up

Export Citation Format

Share Document