Vascular plant communities of a polar oasis at Alexandra Fiord (79° N), Ellesmere Island, Canada

1989 ◽  
Vol 67 (4) ◽  
pp. 1126-1136 ◽  
Author(s):  
M. Muc ◽  
B. Freedman ◽  
J. Svoboda
Keyword(s):  
Cluster Analysis ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Vascular Plants ◽  
Vascular Plant ◽  
Detrended Correspondence Analysis ◽  
High Arctic ◽  
Ellesmere Island ◽  
Community Types

A cluster analysis was used to apportion 136 stands in a High Arctic lowland among six vascular plant community types. These communities are described on the basis of the average prominence values of vascular species and the total cover of macroalgae, bryophytes, lichens, and vascular plants within the designated clusters of stands. The relationships among the community types was explored by a detrended correspondence analysis. The ordination of stands showed considerable floristic overlap among the most widespread plant communities on the lowland. This largely reflects the microtopographic heterogeneity of the sites, the relatively depauperate flora of the High Arctic, and the considerable ecological amplitude of the most prominent vascular plant species.

scholarly journals Plant Community Analysis along Environmental Gradients in Moist Afromontane Forest of Gerba Dima, South-western Ethiopia

2020 ◽  
Author(s):  
Abyot Dibaba Hundie ◽  
Teshome Soromessa Urgessa ◽  
Bikila Warkineh Dullo
Keyword(s):  
Cluster Analysis ◽  
Species Diversity ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Environmental Gradients ◽  
Floristic Composition ◽  
Regional Government ◽  
Community Types ◽  
Western Ethiopia

Abstract Background This study was carried out in Gerba Dima Forest, South-Western Ethiopia, to determine the floristic composition, species diversity and community types along environmental gradients. Ninety sample plots having a size of 25 × 25 m (625 m2) were laid by employing stratified random sampling. Nested plots were used to sample plants of different sizes and different environmental variables. All woody plant species with Diameter at breast height (DBH) ≥ 2.5 cm and height ≥ 1.5 m were recorded in 25 m X 25 m plots. Within the major plots, five 3 m x 3 m subplots (9 m2) was used to collect shrubs with dbh < 2.5 cm and > 1.5 m height. Within each 9 m2subplots, two 1 m2 subplots were used to collect data on the species and abundance of herbaceous plants. Hierarchical (agglomerative) cluster analysis was performed using the free statistical software R version 3.6.1 using package cluster to classify the vegetation into plant community types. Redundancy Analysis (RDA) ordination was used in describing the pattern of plant communities along an environmental gradient. Result One hundred and eighty plant species belonging to 145 genera, 69 families and comprising of 15 endemic species were recorded. Cluster analysis resulted in five different plant communities and this result was supported by the ordination result. RDA result showed altitude was the main environmental variable in determining the plant communities. The ANOVA test indicated that the five community types differ significantly from each other with regard to EC and K. Conclusions The studied forest can play a significant role in biodiversity conservation since it harbours high species diversity and richness. Thus, all Stakeholders including Oromia Forest and wildlife enterprise (OFWE) and the regional government should work to designate the forest as a biosphere reserve and being registered under UNESCO.

scholarly journals Plant Community Analysis along Environmental Gradients in Moist Afromontane Forest of Gerba Dima, South-western Ethiopia

2021 ◽  
Author(s):  
Abyot Dibaba Hundie ◽  
Teshome Soromessa Urgessa ◽  
Bikila Warkineh Dullo
Keyword(s):  
Cluster Analysis ◽  
Species Diversity ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Environmental Gradients ◽  
Floristic Composition ◽  
Endemic Plant ◽  
Community Types ◽  
Western Ethiopia

Abstract Background: This study was carried out in Gerba Dima Forest, South-Western Ethiopia, to determine the floristic composition, species diversity and community types along environmental gradients. Ninety sample plots having a size of 25 X 25m (625m2) were laid by employing stratified random sampling. Nested plots were used to sample plants of different sizes and different environmental variables. All woody plant species with Diameter at breast height (DBH) ≥ 2.5 cm and height ≥ 1.5m were recorded in 25 m X 25 m plots. Hierarchical (agglomerative) cluster analysis was performed using the free statistical software R version 3.6.1 using package cluster to classify the vegetation into plant community types. Redundancy Analysis (RDA) ordination was used in describing the pattern of plant communities along an environmental gradient. Result: One hundred and eighty plant species belonging to 145 genera, 69 families and comprising of 15 endemic species were recorded. Of these, 52 species (28.9%) were trees, 6 species (3.33%) were Trees/shrubs, 31 species (17.22%) were shrubs, 76 species (42.22%) were herbs, and 15 species (8.33%) were Lianas. Rubiaceae, Acanthaceae and Asteraceae were the richest family each represented by 11 genera and 11 species (6.11%), 9 genera and 11 species (6.11%), 6 genera and 11 species (6.11%), respectively of total floristic composition. Cluster analysis resulted in five different plant communities and this result was supported by the ordination result. RDA result showed altitude was the main environmental variable in determining the plant communities. The ANOVA test indicated that the five community types differ significantly from each other with regard to Electrical Conductivity and Potassium. Conclusions: Description of floristic diversity of species in Gerba Dima forest revealed the presence of high species diversity and richness. The presence of endemic plant species in the study forest shows the potential of the area for biodiversity conservation.

scholarly journals Plant Community Analysis along Environmental Gradients in Moist Afromontane Forest of Gerba Dima, South-western Ethiopia

2020 ◽  
Author(s):  
Abyot Dibaba Hundie ◽  
Teshome Soromessa Urgessa ◽  
Bikila Warkineh Dullo
Keyword(s):  
Cluster Analysis ◽  
Species Diversity ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Environmental Gradients ◽  
Regional Government ◽  
Afromontane Forest ◽  
Community Types ◽  
Western Ethiopia

Abstract Background: This study was carried out in Gerba Dima Forest, South-Western Ethiopia, to determine the floristic composition, species diversity and community types along environmental gradients. Ninety sample plots having a size of 25 X 25m (625m 2 ) were laid by employing stratified random sampling. Nested plots were used to sample plants of different sizes and different environmental variables. All woody plant species with Diameter at breast height (DBH) ≥ 2.5 cm and height ≥ 1.5m were recorded in 25 m X 25 m plots. Within the major plots, five 3m x 3m subplots (9m 2 ) was used to collect shrubs with dbh < 2.5 cm and > 1.5m height. Within each 9m 2 subplots, two 1m 2 subplots were used to collect data on the species and abundance of herbaceous plants. Hierarchical (agglomerative) cluster analysis was performed using the free statistical software R version 3.6.1 using package cluster to classify the vegetation into plant community types. Redundancy Analysis (RDA) ordination was used in describing the pattern of plant communities along an environmental gradient. Result: One hundred and eighty plant species belonging to 145 genera, 69 families and comprising of 15 endemic species were recorded. Cluster analysis resulted in five different plant communities and this result was supported by the ordination result. RDA result showed altitude was the main environmental variable in determining the plant communities. The ANOVA test indicated that the five community types differ significantly from each other with regard to EC and K. Conclusions: The studied forest can play a significant role in biodiversity conservation since it harbours high species diversity and richness. Thus, all Stakeholders including Oromia Forest and wildlife enterprise (OFWE) and the regional government should work to designate the forest as a biosphere reserve and being registered under UNESCO. Keyword s: Gerba Dima; Indicator species; Moist Afromontane Forest; Species diversity

scholarly journals Phytosociological surveys: tools for weed science?

2013 ◽  
Vol 31 (2) ◽  
pp. 469-482 ◽  
Author(s):  
G. Concenço ◽  
M. Tomazi ◽  
I.V.T. Correia ◽  
S.A. Santos ◽  
L. Galon
Keyword(s):  
Cluster Analysis ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Distinct Group ◽  
Weed Science ◽  
Comprehensive Overview ◽  
Ecological Evaluation ◽  
Natural Plant ◽  
Ecological Basis

In simple terms, a phytosociological survey is a group of ecological evaluation methods whose aim is to provide a comprehensive overview of both the composition and distribution of plant species in a given plant community. To understand the applicability of phytosociological surveys for weed science, as well as their validity, their ecological basis should be understood and the most suitable ones need to be chosen, because cultivated fields present a relatively distinct group of selecting factors when compared to natural plant communities. For weed science, the following sequence of steps is proposed as the most suitable: (1) overall infestation; (2) phytosociological tables/graphs; (3) intra-characterization by diversity; (4) inter-characterization and grouping by cluster analysis. A summary of methods is established in order to assist Weed Science researchers through their steps into the realm of phytosociology.

scholarly journals The invasive herb Lupinus polyphyllus can reduce plant species richness independently of local invasion age

2021 ◽  
Author(s):  
Marju Prass ◽  
Satu Ramula ◽  
Miia Jauni ◽  
Heikki Setälä ◽  
D. Johan Kotze
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Vascular Plant ◽  
Plant Species Richness ◽  
Ecological Impacts ◽  
Plant Community Composition ◽  
Lupinus Polyphyllus ◽  
Local Invasion

AbstractThe ecological impacts of invasive species may change or accumulate with time since local invasion, potentially inducing further changes in communities and the abiotic environment. Yet, time since invasion is rarely considered when investigating the ecological impacts of invasive non-native species. To examine the effect of time since invasion on the ecological impacts of Lupinus polyphyllus, a perennial nitrogen-fixing herb, we surveyed vascular plant communities in the presence and absence of L. polyphyllus in young, intermediate, and old semi-natural grassland sites (ca. 5, 10, 15 years representing both time since lupine invasion and plant community age). We analyzed vascular plant community composition, vascular plant species richness, and the cover of various ecological plant groups and L. polyphyllus. In contrast to our hypotheses, we found no change in the mean cover of L. polyphyllus (about 35%) with time since local invasion, and an ordination did not suggest marked changes in plant community composition. L. polyphyllus was associated with lower species richness in invaded plant communities but this effect did not change with time since invasion. Invaded plant communities were also associated with lower occurrence of generalist, oligotrophic (low-nutrient-adapted) and copiotrophic (nutrient-demanding) species but no temporal dynamics were detected. We conclude that even the intermediate cover of L. polyphyllus can reduce plant species richness, but the ecological impact caused by this invader might not dramatically change or accumulate with time since invasion.

Plant community and diversity change due to localized permafrost dynamics in bogs of western Canada

2001 ◽  
Vol 79 (8) ◽  
pp. 983-993 ◽  
Author(s):  
David W Beilman
Keyword(s):  
Multidimensional Scaling ◽  
Plant Community ◽  
Plant Communities ◽  
Vascular Plants ◽  
Species Turnover ◽  
Vascular Plant ◽  
Western Canada ◽  
Permafrost Degradation ◽  
Southern Limit ◽  
Metric Multidimensional Scaling

Localized permafrost formation and melt at the southern limit of permafrost has a large effect on boreal bog plant community structure and diversity in continental western Canada (Alberta, Saskatchewan, and Manitoba). Non-metric multidimensional scaling ordinations show that non-permafrost-affected bogs, areas currently underlain by permafrost (frost mounds), and areas of permafrost degradation (internal lawns) have distinct plant communities. Bryophytes respond more strongly than vascular plants to lengthened environmental gradients in the bogs studied. Seventy-two vascular plant and bryophyte species were found, with mean alpha diversity (species richness) similar in bogs and internal lawns (22.6 and 22.1) and lowest on frost mounds (15.6). Beta diversity (species turnover between landforms) is greater for bryophytes (4.22) than vascular plants (2.54). Comparisons within internal lawns show highly variable height above water table, community composition, and species diversity in wet communities and reduced variability as peat accumulates and converges on dry surfaces dominated by Sphagnum fuscum (Schimp.) Klinggr. Overall, localized permafrost dynamics increase bog plant diversity by 47% by introduction of unique dry, shaded (frost mound) and wet, open (internal lawn) conditions absent from non-permafrost-affected bogs, making localized permafrost bogs one of the most bryologically diverse peatland types in western Canada.Key words: peatlands, bryophytes, plant communities, non-metric multidimensional scaling ordination, permafrost, climate change.

Threatened dry grasslands in the continental boreal forests of Wood Buffalo National Park

1997 ◽  
Vol 75 (8) ◽  
pp. 1363-1370 ◽  
Author(s):  
A. G. Schwarz ◽  
Ross W. Wein
Keyword(s):  
Plant Species ◽  
Populus Tremuloides ◽  
National Park ◽  
Vascular Plant ◽  
Detrended Correspondence Analysis ◽  
Diversity Indices ◽  
Grassland Species ◽  
Dry Grasslands ◽  
Community Types ◽  
Wood Buffalo National Park

Dry grasslands in Wood Buffalo National Park are unique biological features at 60°N latitude, since they contain plant species normally found in more southern grasslands at 50–55°N latitude. The objectives of this study were to inventory dry grasslands, classify them according to similarity of species cover, and establish relationships with understory species in Populus tremuloides and shrub communities. Dry grasslands were studied at nine sites; most were clustered in the Salt River and Peace Point areas. The largest unit of grassland was about 3.0 ha, and most units were less than 0.5 ha. This contrasts with the hundreds of hectares recorded earlier in the century. Of the 128 vascular plant species identified, 29 are considered as southern, and of these, 15 are regionally rare. Sixty-four plots were classified into nine community types, using two-way indicator species analysis. A group of six communities were dominated by grass and shrub species with a component of southern grassland species. Three communities, strongly dominated by Populus and shrubs, represent community types that invade dry grasslands. Ordination of plots using detrended correspondence analysis showed relationships among the community types and a clear separation of southern grassland species from those found in forest communities. Vascular plant diversity, as represented by mean species richness, ranged from about 15 to 28, and Shannon diversity indices ranged from 1.883 to 2.615. The cover of southern grassland species was negatively correlated (correlation coefficient of −0.524) with cover of tall shrubs and trees, suggesting that the dry grasslands of Wood Buffalo National Park are threatened by tree and shrub invasion, which is due, in part, to a lack of recent fires at these sites. Key words: northern grasslands, biodiversity, endangered species, endangered spaces.

Vegetation of stressed calcareous screes and slopes in Sverdrup Pass, Ellesmere Island, Canada

1992 ◽  
Vol 70 (12) ◽  
pp. 2359-2377 ◽  
Author(s):  
Paul F. Maycock ◽  
Dianne Fahselt
Keyword(s):  
Quantitative Analysis ◽  
Environmental Factors ◽  
Plant Communities ◽  
Vascular Plants ◽  
High Arctic ◽  
Ellesmere Island ◽  
Canadian High Arctic ◽  
Polar Desert ◽  
Wide Range ◽  
Mountain Systems

Although calcareous erosional mountain systems such as those in central Ellesmere Island constitute extremely limiting environments and are sometimes even considered to be totally unvegetated, quantitative analysis of vegetation revealed 156 species, 81 of which were lichens. Although cryptogams of such depauperate landscapes in the Canadian High Arctic have often been overlooked in vegetational studies, it was found that lichens serve as reliable ecological markers, and under the most limiting conditions, 11 species occurred as major dominants. The system also supported 37 bryophytes that in poor sites were dwarfed and sterile but that served as dominants under somewhat better conditions. Thirty-eight species of vascular plants were found, 7 of which were major dominants in less limiting environments. A wide range of both environmental factors and plant communities were found under the marginal conditions of the cliff, slope, and scree system. Key words: vegetation, lichens. High Arctic, polar desert, semipolar desert.

Plant community evolution in a glacier foreland of the Central European Alps

2020 ◽  
Author(s):  
Katharina Ramskogler ◽  
Svenja Müller ◽  
Bettina Knoflach ◽  
Johann Stötter ◽  
Clemens Geitner ◽  
...  
Keyword(s):  
Species Composition ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Primary Succession ◽  
Vascular Plant ◽  
Soil Parameters ◽  
European Alps ◽  
Central European ◽  
Vascular Plant Species

&lt;p&gt;Glacier forelands are perfect for analysing the development of plant communities from zero onward. According to Matthews (1992), the chronosequence can act as a spatial representation of the temporal sequence. Therefore, it is ideal to analyse changes in landscape and land cover in time slices. Development of plant communities does not only depend on the age of the deposits, but also on topography, microclimate, soil development, and geomorphological processes as well as on biotic interactions. In the long term, permanent plots represent an adequate method to follow the colonisation on differently aged terrain throughout time.&lt;/p&gt;&lt;p&gt;The main research question of the study is: Do cryospheric changes influence plant community development in time and space? During the first study year we were focused on the following questions: i) How fast does a plant community evolve? ii) How many species do occur on different moraine stages? iii) How do soil parameters correlate with primary succession stages?&lt;/p&gt;&lt;p&gt;The study site is located in the southern part of the Central European Alps, Martell Valley (South Tyrol, Italy). We established 12 permanent plot clusters of 2 x 5 m on areas deglaciated between 1985 and 2018, two per retreat area. In each square meter of these clusters, species composition, cover, and number of individuals were sampled. On the ground moraines of the glacier stages 1911 and approximately 1850 we recorded species composition and cover on 10 x 10 m plots (four plots in total). In all plot clusters and plots on the old moraines, soil temperature and soil water potential as well as relevant soil parameters were measured.&lt;/p&gt;&lt;p&gt;We found up to two vascular plant species per square meter on areas ice free for one year and up to 16 vascular plant species per square meter on areas ice free since 1985.&lt;/p&gt;&lt;p&gt;On the moraines of 1911 were up to 39 vascular plant species per plot with a mean cover of 52.5 %. On the moraines of 1850 we found up to 43 vascular plant species with a mean cover of 40 %.&lt;/p&gt;&lt;p&gt;In the next step we will analyse the effects of pioneer, early and late successional species on morphodynamic processes and their response to these processes using functional traits.&lt;/p&gt;&lt;p&gt;Matthews, J.A. (1992): The ecology of recently-deglaciated terrain: a geoecological approach to glacier forelands and primary succession. Cambridge University Press, Cambridge.&lt;/p&gt;

scholarly journals Ecological and floristic study of Hirmi woodland vegetation in Tigray Region, Northern Ethiopia

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Mehari Girmay ◽  
Tamrat Bekele ◽  
Sebsebe Demissew ◽  
Ermias Lulekal
Keyword(s):  
Species Diversity ◽  
Plant Species ◽  
Plant Community ◽  
Plant Communities ◽  
Vegetation Structure ◽  
Floristic Composition ◽  
Individual Species ◽  
Shannon Diversity ◽  
Regeneration Status ◽  
Community Types

Abstract The dryland area in Ethiopia covers a substantial region endowed with diverse plant resources. However, the landmass has received less attention even if it has high ecological, environmental, and economic uses. The present study was conducted in Hirmi woodland vegetation, which is one of the dryland areas in Ethiopia, with the objective of investigating the floristic composition, plant community types, vegetation structure, community-environment relations and its regeneration status. Vegetation and environmental data were collected from 80 sampling plots with a size of 25 m × 25 m designated as the main plots. Diameter at breast height (DBH), height, basal area, density, vertical structure, importance value index (IVI), and frequency were computed. Species diversity and evenness were analyzed using Shannon diversity and evenness indices. The plant community types and vegetation-environment relationships were analyzed using classification and ordination tools, respectively. A total of 171 vascular plant species belonging to 135 genera and 56 families were recorded. About 5.3% of the species were endemic and near-endemic to Ethiopia. The highest number of species was recorded in families Fabaceae (16.4%) and Poaceae (11.7%) followed by Asteraceae (7.0%), Combretaceae, Lamiaceae, and Moraceae (3.5% each). Five plant communities were identified. According to the results from ordination analysis, the floristic composition of these plant communities was significantly affected by altitude, slope, sand, silt, soil organic matter, total nitrogen, and disturbance. The vegetation structure reveals that a large number of individual species was categorized in the lower DBH, frequency, and height classes. The highest Shannon diversity index and evenness values of the study area were 4.21 and 0.95, respectively. Anogeissus leiocarpa, Combretum hartmannianum, Ziziphus mucronata, Terminalia macroptera, and Acacia polyacantha were the species with high IVI. Some endemic plants were in the IUCN red list categories of Ethiopia and Eritrea. The overall regeneration status of the study area was poor because of anthropogenic disturbances and grazing pressures. Although the study area is endowed with high plant species diversity including endemism, it is under poor regeneration status due to various disturbances. To overcome this challenge, integrated management measures including monitoring and application of restoration techniques by taking into consideration the significant environmental factors associated with species diversity as well as observed regeneration status and IUCN threat level of the species are highly recommended.

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