Five short pollen diagrams of soils from Jan Mayen, Norway: a testimony of a dynamic landscape

1987 ◽  
Vol 5 (2) ◽  
pp. 193-206 ◽  
Author(s):  
W. O. VAN DER KNAAP
Keyword(s):  
Pollen Diagrams ◽  
Dynamic Landscape

scholarly journals Dynamic Landscape Connectivity Special Issue Editorial

Land ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 555
Author(s):  
Megan K. Jennings ◽  
Katherine A. Zeller ◽  
Rebecca L. Lewison
Keyword(s):  
Landscape Connectivity ◽  
Special Issue ◽  
Dynamic Landscape ◽  
Landscape Feature

Until fairly recently, the majority of landscape connectivity analyses have considered connectivity as a static landscape feature, despite the widespread recognition that landscapes and the abiotic and biotic processes that influence them are dynamic [...]

scholarly journals The landscape of alternative polyadenylation in single cells of the developing mouse embryo

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Vikram Agarwal ◽  
Sereno Lopez-Darwin ◽  
David R. Kelley ◽  
Jay Shendure
Keyword(s):  
Rna Binding ◽  
Developmental Stages ◽  
Single Cells ◽  
Neuronal Cell ◽  
Alternative Polyadenylation ◽  
Cell Types ◽  
Untranslated Regions ◽  
Mammalian Development ◽  
Translation Rate ◽  
Dynamic Landscape

Abstract3′ untranslated regions (3′ UTRs) post-transcriptionally regulate mRNA stability, localization, and translation rate. While 3′-UTR isoforms have been globally quantified in limited cell types using bulk measurements, their differential usage among cell types during mammalian development remains poorly characterized. In this study, we examine a dataset comprising ~2 million nuclei spanning E9.5–E13.5 of mouse embryonic development to quantify transcriptome-wide changes in alternative polyadenylation (APA). We observe a global lengthening of 3′ UTRs across embryonic stages in all cell types, although we detect shorter 3′ UTRs in hematopoietic lineages and longer 3′ UTRs in neuronal cell types within each stage. An analysis of RNA-binding protein (RBP) dynamics identifies ELAV-like family members, which are concomitantly induced in neuronal lineages and developmental stages experiencing 3′-UTR lengthening, as putative regulators of APA. By measuring 3′-UTR isoforms in an expansive single cell dataset, our work provides a transcriptome-wide and organism-wide map of the dynamic landscape of alternative polyadenylation during mammalian organogenesis.

scholarly journals Testing the potential of pollen assemblages to capture composition, diversity and ecological gradients of surrounding vegetation in two biogeographical regions of southeastern Europe

2021 ◽  
Author(s):  
Maria Papadopoulou ◽  
Ioannis Tsiripidis ◽  
Sampson Panajiotidis ◽  
Georgios Fotiadis ◽  
Daniel Veres ◽  
...  
Keyword(s):  
Vegetation Structure ◽  
Diversity Indices ◽  
Life Forms ◽  
Ecological Gradients ◽  
Vegetation Diversity ◽  
North Central ◽  
Plant Life Forms ◽  
Pollen Diagrams ◽  
Biogeographical Regions ◽  
Species Specific

AbstractDue to the complex relationship between pollen and vegetation, it is not yet clear how pollen diagrams may be interpreted with respect to changes in floristic diversity and only a few studies have hitherto investigated this problem. We compare pollen assemblages from moss samples in two southeastern European forests with the surrounding vegetation to investigate (a) their compositional similarity, (b) the association between their diversity characteristics in both terms of richness and evenness, and (c) the correspondence of the main ecological gradients that can be revealed by them. Two biogeographical regions with different vegetation characteristics, the Pieria mountains (north central Greece) and the slopes of Ciomadul volcano (eastern Romania), were chosen as divergent examples of floristic regions, vegetation structure and landscape openness. Pollen assemblages are efficient in capturing the presence or absence, rather than the abundance in distribution of plants in the surrounding area and this bias increases along with landscape openness and vegetation diversity, which is higher in the Pieria mountains. Pollen assemblages and vegetation correlate better in terms of richness, that is, low order diversity indices. Relatively high correlation, in terms of evenness, could be potentially found in homogenous and species poor ecosystems as for Ciomadul. Composition and diversity of woody, rather than herb, vegetation is better reflected in pollen assemblages of both areas, especially for Pieria where a direct comparison of the two components was feasible, although this depends on the species-specific pollen production and dispersal, the openness of landscape and the overall diversity of vegetation. Gradients revealed by pollen assemblages are highly and significantly correlated with those existing in vegetation. Pollen assemblages may represent the vegetation well in terms of composition, diversity (mainly richness) and ecological gradients, but this potential depends on land use, vegetation structure, biogeographical factors and plant life forms.

scholarly journals COVID 19: Designing and conducting an online mini-multiple interview (MMI) in a dynamic landscape

2020 ◽  
Vol 42 (7) ◽  
pp. 776-780 ◽  
Author(s):  
Jennifer Cleland ◽  
Jowe Chu ◽  
Samuel Lim ◽  
Jamie Low ◽  
Naomi Low-Beer ◽  
...  
Keyword(s):  
Dynamic Landscape

Dynamic landscape of immune cell-specific gene regulation in immune-mediated diseases

Cell ◽  
2021 ◽  
Author(s):  
Mineto Ota ◽  
Yasuo Nagafuchi ◽  
Hiroaki Hatano ◽  
Kazuyoshi Ishigaki ◽  
Chikashi Terao ◽  
...  
Keyword(s):  
Gene Regulation ◽  
Immune Cell ◽  
Specific Gene ◽  
Immune Mediated ◽  
Dynamic Landscape

Pollen evidence for the postglacial origins of Nova Scotia's forests

1987 ◽  
Vol 65 (6) ◽  
pp. 1163-1179 ◽  
Author(s):  
David G. Green
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
New England ◽  
Ice Sheets ◽  
Arrival Times ◽  
Local Environments ◽  
Pollen Diagrams ◽  
Propagule Dispersal ◽  
Coastal Shelf ◽  
Maritime Canada

Pollen diagrams from sites in southwest Nova Scotia and close to the New Brunswick – Nova Scotia border show that after retreat of the Wisconsin ice sheets, most tree taxa arrived in the extreme southwest of Nova Scotia earlier than anywhere else in the province. For most tree taxa, arrival times at sites in maritime Canada and in northeastern New England are consistent with very early dispersal of individuals along the coastal strip via the exposed coastal shelf and with their entering Nova Scotia from the southwest. These scattered pioneer populations acted as centres for major population expansions, which followed much later in some cases. Local environments, fire, and interspecies competition appear to have been more important than propagule dispersal rates as factors limiting the spread of most taxa.

Pollen diagrams from interior Labrador

1970 ◽  
Vol 48 (11) ◽  
pp. 1957-1975 ◽  
Author(s):  
Alastair Morrison
Keyword(s):  
Primary Succession ◽  
Vegetation Changes ◽  
Bare Ground ◽  
Radiocarbon Dates ◽  
River Watershed ◽  
Pollen Diagrams ◽  
Glacier Ice ◽  
Lake Waters

Six pollen zones can be distinguished in interior Labrador. The earlier zones represent the primary succession of vegetation from bare ground to boreal woodland or forest, which occupied about 500 years between 5700 and 5200 B.P. There have been only minor fluctuations in the nature of the vegetation since 5200 B.P. Radiocarbon dates show that the zones are contemporaneous over that part of the Lake Plateau within the Churchill River watershed, but similar vegetation changes occurred 1000 years earlier in the Kaniapiskau basin, further north, in New Quebec. These two areas must have been freed of a cover of glacier ice or lake waters immediately before 5700 B.P. and 6700 B.P. respectively.

Sign in / Sign up

Export Citation Format

Share Document