Ordination by detrended correspondence analysis (DCA) of the vegetation of Swartboschkloof, Jonkershoek, Cape Province

Bothalia ◽  
1987 ◽  
Vol 17 (1) ◽  
pp. 121-129 ◽  
Author(s):  
D. J. Mcdonald
Keyword(s):  
Soil Moisture ◽  
Plant Communities ◽  
Correspondence Analysis ◽  
Detrended Correspondence Analysis ◽  
Vegetation Classification ◽  
Environmental Data ◽  
Strongly Correlated ◽  
Intensive Study ◽  
Dca Ordination ◽  
Soil Moisture Status

The data of a Braun-Blanquet vegetation classification was ordinated using detrended correspondence analysis (DCA). This was done at the Fynbos Biome intensive study site, Swartboschkloof, Jonkershoek, to investigate the factors determining the distribution of the plant communities. Superimposition of environmental data on the DCA ordination confirmed the indications of the Braun-Blanquet classification that the distribution of plant communities is most strongly correlated with soil geology and, to a lesser extent, with soil moisture status. The ordination also proved useful for examining the relationships between the transitional communites and the distinct communities of Swartboschkloof.

scholarly journals The vegetation types and management units of Goedverwacht farm in the mixed bushveld of the Northern Province, South Africa

Koedoe ◽  
1997 ◽  
Vol 40 (2) ◽  
Author(s):  
L. Breebaart ◽  
M. Deutschlander
Keyword(s):  
Plant Communities ◽  
Correspondence Analysis ◽  
Canonical Correspondence Analysis ◽  
Environmental Gradient ◽  
Detrended Correspondence Analysis ◽  
Northern Province ◽  
Computer Programme ◽  
Data Set ◽  
Management Units ◽  
Floristic Data

An analysis of the vegetation of Goedverwacht farm in the mixed bushveld of the Northern Province is presented. Releves were compiled in 33 stratified random sample plots. Eight distinct plant communities were identified by means ofBraun-Blanquet pro-cedures. Detrended correspondence analysis (DCA) was applied to the floristic data set using the computer programme DECORANA (Detrended Correspondence Analysis) to determine a probable environmental gradient and to facilitate in the identification of management units. The computer programme CANOCO (Canonical Correspondence Analysis) was used to apply canonical correspondence analysis (CCA) to the floristic data set. Two management units were determined by means of vegetation ordinations and soil data. A classification, description and ecological interpretation of the plant communities as well as a description of the management units are presented.

scholarly journals How do plant communities and flower visitors relate? A case study of semi-natural xerothermic grasslands

2013 ◽  
Vol 82 (2) ◽  
pp. 99-105 ◽  
Author(s):  
Damian Chmura ◽  
Paweł Adamski ◽  
Zygmunt Denisiuk
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Plant Communities ◽  
Correspondence Analysis ◽  
Positive Relationship ◽  
Detrended Correspondence Analysis ◽  
Permanent Plots ◽  
Moisture Index ◽  
Rarefaction Analysis ◽  
Flower Visitors

<p>The paper examines the relationships between the species composition of flower visitors and plants in the semi-natural xerothermic grasslands in southern and central Poland. Thirty 10 × 10 m permanent plots were laid out in total, mainly in nature reserves. The vegetation units studied were classified according to the Braun-Blanquet system; these were phytocoenoses of the <em>Festuco-Brometea</em> classes <em>Inuletum ensifoliae</em>, <em>Adonido-Brachypodietum pinnati</em> and the transitional plant community. Entomological research was performed using the Pollard method within the same plots. A particular site was visited only once and different sites were studied between April and August 2008. We applied, among others, co-correspondence-analysis Co-CA, detrended correspondence analysis (DCA) and redundancy analysis (RDA) to investigate the co-occurrence patterns of plants and flower visitors and their biotopic requirements. We found that the species composition of flower visitors cannot be predicted by floristic composition when the duration of the study is restricted to one day (but under similar weather conditions); however, there is a positive relationship between the species richness of insects and plants and a positive relationship between the number of plant species and the abundance of flower visitors. The Ellenberg moisture index and the cover of meadow species significantly explained the species composition of insects. The three various vegetation units and five dominant xerothermic species, i.e. <em>Adonis vernalis</em>, <em>Anemone sylvestris</em>, <em>Inula ensifolia</em>, <em>Linum hirsutum</em> and <em>Carlina onopordifolia</em> that were studied across time differed in the species richness of insects. Our results demonstrate that possible patterns in the species composition and the assembly rules of flower visitors are not apparent when the Pollard method is applied. Based on the data obtained using this method, the flower visiting assemblages seem not to be driven by competition and they primarily show a tendency to co-occur which can be an artifact. A plant-focused method that included a rarefaction analysis yielded more insightful results and shed more light on the differences between the dominant plants that shape the physiognomy of plant communities in a possible pollination specialization.</p>

Spatial and temporal stability of commercial groundfish assemblages off Oregon and Washington as inferred from Oregon trawl logbooks

2000 ◽  
Vol 57 (12) ◽  
pp. 2443-2454 ◽  
Author(s):  
Yong-Woo Lee ◽  
David B Sampson
Keyword(s):  
Correspondence Analysis ◽  
Temporal Stability ◽  
Detrended Correspondence Analysis ◽  
Hierarchical Cluster ◽  
General Linear Model ◽  
Multivariate Methods ◽  
Strongly Correlated ◽  
Study Region ◽  
Spatial And Temporal Characteristics ◽  
Logbook Data

Spatial and temporal characteristics of species compositions for 15 major commercial groundfish species off Oregon and Washington (U.S.A.) were studied using Oregon bottom trawl logbook data from 1987 to 1993. Screening procedures to remove questionable data from the original logbook files resulted in the exclusion of information from 46% of the total available tows. Two multivariate methods, detrended correspondence analysis and Ward's hierarchical cluster analysis, were used to derive species ordinations and groupings. A general linear model developed for the primary detrended correspondence analysis axis scores showed that the species compositions were strongly correlated with depth and minimally correlated with the other environmental variables examined (latitude, month, and year). However, there were distinct seasonal changes in species composition at the shallower depths, consistent with the movement of deepwater species onto the shelf during summer. Annual trends in the species compositions were not evident even though the study region is very dynamic oceanographically and was heavily fished during the study period.

Gradient analysis of forests of the Sangre de Cristo Range, Colorado

1990 ◽  
Vol 68 (1) ◽  
pp. 193-201 ◽  
Author(s):  
Robert B. Allen ◽  
Robert K. Peet
Keyword(s):  
Correspondence Analysis ◽  
Soil Ph ◽  
Populus Tremuloides ◽  
Environmental Gradients ◽  
Detrended Correspondence Analysis ◽  
Base Saturation ◽  
Strongly Correlated ◽  
Moisture Index ◽  
Compositional Gradient ◽  
Sangre De Cristo

Interrelationships between dominant compositional and environmental gradients were studied using 186 forest stands sampled on the east slope of the Sangre de Cristo Range, Colorado. Detrended correspondence analysis and detrended canonical correspondence analysis were used to analyze indirect and direct gradients, respectively. The dominant compositional gradient was strongly correlated with elevation. Increasing elevation was associated with decreasing soil pH and percent base saturation, and increasing total soil N. Ordination of stands stratified by elevation showed the major compositional gradient within each elevation class was strongly correlated with a topographic moisture index. Most soil variables correlated with this gradient in low and high elevation classes. In mid-elevation forests, a third compositional gradient correlated with soil pH, percent base saturation, and potential solar radiation. In these forests, Pinus contorta and Pseudotsuga menziesii were associated with acidic soils on north-facing slopes, whereas Populus tremuloides and Abies concolor were associated with base-rich soils on south-facing slopes. Ordination axes accounted for least variation in comparatively young mid-elevation forests. A plausible explanation is that the mid-elevation forests represent an unpredictable stage in forest development where competition has not yet had sufficient time to sort species along environmental gradients.

Plant communities structure and composition in three coastal wetlands in southern Apulia (Italy)

Biologia ◽  
2011 ◽  
Vol 66 (6) ◽  
Author(s):  
Valeria Tomaselli ◽  
Romeo Pietro ◽  
Saverio Sciandrello
Keyword(s):  
Multidimensional Scaling ◽  
Plant Communities ◽  
Correspondence Analysis ◽  
Coastal Wetlands ◽  
Detrended Correspondence Analysis ◽  
Sandy Soils ◽  
Coastal Areas ◽  
New Associations ◽  
Ephemeral Plant ◽  
Similarity Ratio

AbstractIn this paper the results of a study on the composition and the distribution of the plant communities in three coastal areas of southern Apulia are presented. A total of about 180 vegetation relevés were performed following the Braun-Blanquet phytosociological method. Vegetation data were analysed using both classification (UPGMA, similarity ratio) and ordination methods (including Non-metric Multidimensional Scaling (NMS) and Detrended Correspondence Analysis (DCA). The relevés are distributed in the following classes: Molinio-Arrhenateretea, Phragmito-Magnocaricetea, Juncetea maritimi, Sarcocornietea fruticosae, Saginetea maritimae, Thero-Salicornietea, Helianthemetea guttati. Detailed information about structure and zoning of the detected plant communities are here provided. Two new associations, belonging to the Alkanno-Maresion nanae alliance (microphytic ephemeral plant communities growing on sandy soils, Helianthemetea guttati class) have been described here, both in the “Torre Guaceto” site. The area of “Le Cesine” showed the highest total number of plant communities, while the “Saline di Punta della Contessa” site revealed the largest number of Sarcocornietea fruticosae plant communities.

scholarly journals Effects of natural broadleaved regeneration vs conifer restoration on the herb layer and microclimate

2016 ◽  
Vol 68 (3) ◽  
pp. 483-493
Author(s):  
Dragana Vukov ◽  
Zoran Galic ◽  
Marko Rucando ◽  
Milos Ilic ◽  
Mirjana Cuk ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Correspondence Analysis ◽  
Detrended Correspondence Analysis ◽  
Beech Forest ◽  
Douglas Fir ◽  
Pteridium Aquilinum ◽  
Permanent Plots ◽  
Herb Layer ◽  
Forest Stands ◽  
Floristic Similarity

This study was carried out on the Vidlic Mountain, eastern Serbia. The herb layer was surveyed in permanent plots on two localities: in a naturally regenerated beech forest and in a Douglas-fir plantation, in spring, summer and autumn 2011, 2012 and 2013. Air temperature, air humidity and soil moisture were measured. Species richness, Shannon?s diversity index and Pielou?s evenness index were calculated for each plot. Comparison of the abundances of species common to both forest stands was done using the Mann-Whitney U-test. The compositional gradient of the species data was examined using detrended correspondence analysis (DCA), and the species-environment relationship was analyzed by canonical correspondence analysis (CCA). Soil moisture and the total herb cover significantly differed in the naturally regenerated beech forest and Douglas-fir plantation. Floristic similarity between the surveyed forest stands was 28.12%. Although the dominant canopy species is known to be the strongest predictor of the herb layer, the model that includes all of the analyzed environmental factors explains the largest amount of the species variability. The species best fitted to this model are Dryopteris filix-mas, Galium odoratum, Pulmonaria officinalis, Sanicula europaea, Pteridium aquilinum and Rubus caesius. The analyzed forest stands are examples of two different post-disturbance regeneration strategies. Having in mind the limitations of this study, we can conclude that the naturally regenerated beech forest recovers faster: its herbaceous layer indicated nearly natural conditions, with only a few pioneer and disturbance-tolerant species. The herb layer in the Douglas-fir stand is still in the early seral stage, i.e. establishment.

The plant communities of a foredune in southeastern Brazil

1998 ◽  
Vol 76 (8) ◽  
pp. 1323-1330 ◽  
Author(s):  
Raimundo Paulo Barros Henriques ◽  
John DuVall Hay
Keyword(s):  
Species Composition ◽  
Correspondence Analysis ◽  
Stress Gradient ◽  
High Stress ◽  
Detrended Correspondence Analysis ◽  
Southeastern Brazil ◽  
Important Species ◽  
Middle Range ◽  
Dca Ordination ◽  
Using Data

Species composition, biomass and environmental characteristics of a coastal plant community of southeastern Brazil, was studied using data from 110 quadrats collected on the foredune of Barra de Maricá, Rio de Janeiro, Brazil. Indirect and direct gradient analyses were used to describe the foredune community. Ordination by detrended correspondence analysis (DCA) indicated the existence of three vegetation groups: pioneer, embryo dunes and a zone of fixed dunes with blow out areas. The gaps observed between groups were attributed to discontinuities in environmental factors. Most of the variation in species composition was expressed by the second axis of the DCA ordination, which was correlated with the distance from the beach bank. The second axis is interpreted as a stress gradient, with high stress in the pioneer zone decreasing to fixed dunes. The coenocline analyzed by direct gradient ordination, was divided into three segments equivalent to Groups detected by DCA ordination. The important species were: Althernanthera maritima St. Hil. in the pioneer zone, and Sporobolus virginicus (L.) Kunth, Mariscus pedunculatus (R. Brown) T. Koyama, and Mitracarpus frigidum K. Sch. in the embryo dunes. The grassPanicum racemosum (Spreng) was associated with areas of fixed dune. that were also characterized by Mollugo verciticillata L. Both biomass and species richness were lower at the high stress disturbance ends of the gradient, with their maximum value in different portions of the middle range of the gradient.Key words: detrended correspondence analysis, direct gradient analysis, foredune communities, vegetation zonation.

Pattern and vegetation–environment relationships in a boreal forested wetland in northeastern Ontario

1995 ◽  
Vol 73 (4) ◽  
pp. 629-637 ◽  
Author(s):  
John K. Jeglum ◽  
Fangliang He
Keyword(s):  
Correspondence Analysis ◽  
Canonical Correspondence Analysis ◽  
Detrended Correspondence Analysis ◽  
Forested Wetland ◽  
Strongly Correlated ◽  
Loss On Ignition ◽  
Data Set ◽  
Axis I ◽  
Environmental Measures ◽  
Physical And Chemical

A forested wetland data set from northeastern Ontario, consisting of species cover and environmental measures in 43 stands, was analyzed with canonical correspondence analysis. Results showed two main vegetational gradients related to factor complexes of peat depth – moisture (mire margin to mire expanse) and pH–calcium. Stands within each of the vegetation types were positioned closely, and gradients of types were similar to those from earlier analyses, suggesting the validity of a previous classification. Axis I of the ordination was highly related to peat depth, several elements (Al, Fe, and Cu), loss on ignition, bulk density, and water content in peat. Axis II was highly related to loss on ignition, depth of fibric layer, pH, and several elements (Ca, Mg, Mn, and N). The number of species in a plot was strongly correlated to the pH–calcium gradient, whereas vegetation cover was strongly correlated to the peat depth – moisture gradient. Analysis with detrended correspondence analysis gave results very similar to canonical correspondence analysis, suggesting that there was a relatively high correspondence between vegetational and environmental gradients. Environmental measures were partitioned into physical and chemical attributes, to detect the relative contribution to vegetational variation. Both physical and chemical variables were important, and 81% of the variation in vegetation was explained by the environmental measures. Key words: boreal forest, multivariate analysis, Ontario, wetlands, vegetation pattern, diversity.

Second international scientific conference «Present fundamental problems of vegetation classification» (Yalta, 15–20 September 2019)

2019 ◽  
pp. 135-142
Author(s):  
K. V. Ivanova ◽  
A. M. Lapina ◽  
V. V. Neshataev
Keyword(s):  
Plant Communities ◽  
National Archive ◽  
Botanical Garden ◽  
Vegetation Classification ◽  
Scientific Conference ◽  
Scientific Journals ◽  
Time Dynamics ◽  
The Past ◽  
Research Organizations

The 2nd international scientific conference «Fundamental problems of vegetation classification» took place at the Nikitskiy Botanical Garden (Yalta, Republic of Crimea, Russia) on 15–20 September 2019. There were 56 participants from 33 cities and 43 research organizations in Russia. The conference was mostly focused on reviewing the success in classification of the vegetation done by Russian scientists in the past three years. The reports covered various topics such as classification, description of new syntaxonomical units, geobotanical mapping for different territories and types of vegetation, studies of space-time dynamics of plant communities. The final discussion on the last day covered problems yet to be solved: establishment of the Russian Prodromus and the National archive of vegetation, complications of higher education in the profile of geobotany, and the issue of the data leakage to foreign scientific journals. In conclusion, it was announced that the 3rd conference in Nikitskiy Botanical Garden will be held in 2022.

Classification of woody-shrub vegetation of the forest-steppe complex of Privolzhskaya Upland

2009 ◽  
pp. 27-53
Author(s):  
A. Yu. Kudryavtsev
Keyword(s):  
Plant Community ◽  
Plant Communities ◽  
Dominant Species ◽  
Large Scale ◽  
Nature Reserve ◽  
Vegetation Mapping ◽  
Vegetation Classification ◽  
Forest Steppe ◽  
Mapping Data

Diversity of plant communities in the nature reserve “Privolzhskaya Forest-Steppe”, Ostrovtsovsky area, is analyzed on the basis of the large-scale vegetation mapping data from 2000. The plant community classi­fication based on the Russian ecologic-phytocoenotic approach is carried out. 12 plant formations and 21 associations are distinguished according to dominant species and a combination of ecologic-phytocoenotic groups of species. A list of vegetation classification units as well as the characteristics of theshrub and woody communities are given in this paper.

Sign in / Sign up

Export Citation Format

Share Document