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This research was carried out in Idlib Governorate, located in northwestern Syria, during the years 2021, 2022, and 2023. The self-environment of the Crataegus genus was also studied in the study areas, by conducting botanical surveys there, according to the Braun-Blanquet method. The results showed that Crataegus has environmental flexibility as it spreads in multiple bioclimatic environments. Specie Crataegus monogyna belonging to the order Quercetaliapubescentis, which follows the Querceteapubescentis order, whose components are part of the plant alliance Quercioninfectoriae. Which includes deciduous oak forests within the Supra-Mediterranean structure. As for the species C. azarolus, it belongs to the order Quercetaliailicis, which belongs to the class Querceteailicis, and whose components are considered within the botanical alliance QuercionCalliprini within the Eu-Mediterranean structure. In general, the hawthorn did not constitute a characteristic type of species, but was always accompanying species, and did not rise to the level of characteristic types of species included in the designation of plant communities specialized in it. [ABSTRACT FROM AUTHOR]

Background: Grasslands provide a wide range of ecosystem services (ESs). However, there is currently no method for easily diagnosing the level of ESs produced. Our aim was to develop ES indicators based on botanical surveys, which are readily available data and integrative of grassland spatiotemporal variability. Methods: Based on academic knowledge and expertise, we identified several simple vegetation criteria that we aggregated using a multicriteria analysis tool to construct indicators of the level of ESs provided by grasslands. In this study, the indicators were calculated from over 2000 botanical surveys spread over a wide biogeographical gradient. Results: Analyses of correlation between the various indicators show that "forage supply" and "diversity conservation" were not correlated. "Forage availability" and "nitrogen availability for the vegetation" were positively linked together and negatively linked to the robustness of the plant community to extreme events. A temporal approach highlights that the "biodiversity conservation" score decreased from 1970 to 2010 and that "nitrogen availability for the vegetation" was lower in 1970 and 1980 than in 2000 and 2010. Conclusions: These results show that our aggregation method based on a large data set of botanical surveys could be appropriate for studying temporal dynamics of ESs. [ABSTRACT FROM AUTHOR]

The wealth of historical botanical surveys in New England and New York allows ecologists to study changes in plant communities over time across well documented sites. Studies of floristic change in towns, counties, and preserves over the past 150 years reveal regional patterns of species loss and increasing proportions of nonnative species. These changes are often linked to land use change, deer herbivory, development pressures, and climate change. Here, we review patterns of change throughout the region and explore in-depth floristic change at a northern site: Mount Desert Island (MDI), Maine, which holds the largest section of Acadia National Park. We find floras across the region have lost, on average, one-quarter of their native species—ranging from a loss of 3.5% of species from the Finger Lakes Region in New York to a loss of 53.1% of species on Staten Island, New York. No variable that we examine (e.g., size of area, size of flora, conservation status, and data sources) explains differences in losses across all sites. Contemporary floras have higher percentages of nonnative species than historic floras: the percent of nonnatives in floras have increased by 1.5% to 19.7% across the region. We also explore a data set of 412 conspecifics found both on MDI and 324 km away in Concord, Massachusetts, and compare species-level changes in abundance over the past century to test whether changes in one location might be predictive of changes in the other. We find that at a community level, changes in abundance in Concord were predictive of changes on MDI—local floras throughout the region have lost roughly 25% of their original species over the last 50 to 150 years—but changes in abundance for particular species in Concord were not predictive of how the same species changed in abundance on MDI. In New England, analyses of changes in nearby floras may help land managers and scientists understand community-level changes likely taking place, but we find that documenting and understanding changes in particular species requires targeted local study. Finally, we highlight the importance of context: understanding the survey effort, expertise, and goals of earlier botanists allows contemporary ecologists to make the most of the available historical ecological data. [ABSTRACT FROM AUTHOR]

A historical overview of the phytosociological method in Europe is presented. Some methodological and procedural differences in the application of the Braun-Blanquet approach, from the selection of the sampling plots to the assignment of relevés to existing or newly described units, are briefly compared. The main advantages and limitations of the phytosociological vegetation classification are reviewed and discussed, also in light of their applications for vegetation mapping and monitoring. [ABSTRACT FROM AUTHOR]

Aim: To describe the classification approach and protocols that were used in the project Vegetation of the Czech Republic and relate them to the comparative framework for broad-scale plot-based vegetation classification proposed by De Cáceres et al. (2015). This description should facilitate comparison of this national vegetation classification with vegetation classifications in other countries. Location: Czech Republic. Methods: The project Vegetation of the Czech Republic, realized from 1997 to 2013, was based on the analyses of vegetationplot records from the Czech National Phytosociological Database. Associations were defined as the basic hierarchical level using formal definitions created with the Cocktail method. These formal definitions were included in a computer expert system for automatic identification of associations. Evaluation and characterization of associations were based on the groups of plot records assigned to the particular associations by the expert system. Higher classification levels were classified by type-based grouping of associations. A novel statistical method for determining diagnostic species of vegetation types was developed within the project. All the analytical procedures used and developed for the project were included in the JUICE program. Results: The national vegetation classification system was published in a four-volume monograph from 2007 to 2013. It consists of five hierarchical levels with nested vegetation types, including 9 formations, 39 classes, 138 alliances, 496 associations and for some associations also variants. At the same time the project infrastructure, including the expert system and the JUICE program, was published online. Conclusions: The national vegetation classification of the Czech Republic provided novel classification approach and protocols. Several elements of these protocols have been subsequently applied in other countries. At the national level, the classification has found various applications both in nature conservation and in basic research. [ABSTRACT FROM AUTHOR]

The annual Editorial of Phytocoenologia 2018 reflects on the topical coverage of the journal in the years 2015-2017. All continents except Antarctica were present, but contributions from Europe and Asia dominated, South America and Africa were moderately represented and North America and Australia underrepresented. In terms of vegetation types temperate grasslands and forests were the most frequent study subjects, while aquatic and weed communities were hardly addressed at all. We highlight the classification of the petrifying springs in Ireland (Lyons & Kelly 2017, Phytocoenologia 47: 13-32) as a prototypic study we would like to be published in the journal and thus acknowledge the authors with the Editors' Award 2017. Also the two permanent sections, Ecoinformatics (with Long and Short Database Reports) as well as Phytosociological Nomenclature (with nomenclatural proposals and nomenclatural revisions) are important and much used parts of Phytocoenologia. [ABSTRACT FROM AUTHOR]

Playa Delfín is located in southwestern Costa Rica on the Golfo Dulce coast across from the Osa Peninsula, and occupies an area of 115 ha with elevations ranging up to 145 m. The reserve is privately owned by Patrick and Anne Weston, and was purchased in 1988 to protect one of the last remaining tracts of primary forest in the region. A two-week botanical survey in 2011 aimed at assessing the conservation value of the site resulted in the documentation of 138 taxa of chiefly woody plants. Of these 101 were trees, 24 were shrubs, 6 were lianas, and 7 were herbs. Included in the list are twelve species considered to be rare or of restricted ranges, as well as three species representing first reports for the Osa Peninsula/Golfo Dulce region. Four major habitats are described along with typical species associated with each community. Primary forest occurred in the uplands and stream corridors while the lowland section was more disturbed but still contained a number of large trees. Five non-native species were documented in the lowlands but only Gmelina arborea was particularly invasive. These results suggest that a rich flora occurs at Playa Delfín, and, as it was also known to harbor a rich fauna, provides additional evidence of the high conservation value of the site. Already a part of Costa Rica's private forest reserve system, Playa Delfín received additional government protection as a result of this and other studies documenting the biological resources at the reserve. [ABSTRACT FROM AUTHOR]

The distribution of aquatic vegetation and associated community diversity and biomass in the Poyang Lake were investigated. The results showed that (1) 43 species of aquatic vascular plants were found in the Poyang Lake watershed which belonged to 22 families; (2) the vegetation of the Poyang Lake scattered in different areas which could be divided into 31 major plant communities and 5 plant zones including amphibian, emergent, floating-leaved, submerged, and floating input; (3) there were 67 aquatic plants in the lake area, and the standing stock (fresh weight) was 1519.41 t. The number of amphibians was the dominant plant species in the Poyang Lake, and the quantity and percentage of amphibians were predominant, which was far more than the other three life forms. [ABSTRACT FROM AUTHOR]

"VESTA - resurvey of natural, non-forest vegetation (Central Europe)" is a thematic, resurvey database focused on documentation of changes in natural, non-forest communities. Currently, the database includes 549 relevés (231 replots for 84 sites) corresponding to the classes Asplenietea trichomanis (incl. Polypodietea), Koelerio-Corynephoretea (rocky grasslands), Loiseleurio-Vaccinietea and Betulo carpaticae-Alnetea viridis. The project is continuous in character. It is based on the phytosociological relevés from own field studies which have been carried out in the Sudetes Mts. and their foothills since 1989. The subject of research have been all types of rocky communities (chasmophytic, grasslands, thickets), mountain and submountain tall-herb communities, subalpine thickets and heathlands. Relevés are collected according to the standard Braun-Blanquet method (species coverage scale: r, +, 1, 2, 3, 4, 5) and on rectangular or square-shaped surfaces with possible adjustment to the shape of the rocky outcrops. Initially (until 2008), the location of plots was marked on maps and field sketches. However, the fact that all relevés were collected by the owners of the database made it easier to revisit all plots and assigned a location compatible with GPS with SiRFstar III chipset. The accuracy of position measurements varies between 2 and 15 meters (on average 10 meters). Aspect is determined using electronic compass linked to GPS. Altitude is obtained from Google Earth and corrected with landmarks from topographical maps if necessary. The shading of the plots has been visually assessed so far. The bedrock type is derived from a Detailed Geological Map of the Sudetes (http://sudety.pgi.gov.pl/). Subsequent resurveys of the plots are conducted during field visits planned specifically for this purpose or during other research carried out in the same area. [ABSTRACT FROM AUTHOR]

Aim Resurveys of historical vegetation plots are increasingly used for the assessment of decadal changes in plant species diversity and composition. However, historical plots are usually relocated only approximately. This potentially inflates temporal changes and undermines results. Location Temperate deciduous forests in Central Europe. Methods To explore whether robust conclusions can be drawn from resurvey studies despite location uncertainty, we compared temporal changes in species richness, frequency, composition and compositional heterogeneity between exactly and approximately relocated plots. We hypothesized that compositional changes should be lower and changes in species richness should be less variable on exactly relocated plots, because pseudoturnover inflates temporal changes on approximately relocated plots. Results Temporal changes in species richness were not more variable, and temporal changes in species composition and compositional heterogeneity were not higher on approximately relocated plots. Moreover, the frequency of individual species changed similarly on both plot types. Main conclusions The resurvey of historical vegetation plots is robust to uncertainty in original plot location and, when done properly, provides reliable evidence of decadal changes in plant communities. This provides important background for other resurvey studies and opens up the possibility for large-scale assessments of plant community change. [ABSTRACT FROM AUTHOR]

1. Although impacts of alien plants on species richness are widely reported, it remains unclear how common such effects might be and whether they differ from those due to native species. To date, too few studies have examined the impacts of a wide enough spectrum of native and alien species to address the importance of geographic origin on the richness of plant communities. 2. We investigated how total plant species richness, as well as its separate alien and native components, varied with the abundance of 115 alien and 146 native plant species across Banks Peninsula in New Zealand. Using null models, we tested whether significant correlations between the abundance of each focal species and species richness were more frequent than expected by chance. Examination of the differences in the relationships with species abundance found for native and alien richness can shed light as to whether alien species might be acting as drivers of biodiversity change or passengers responding to external environmental factors. 3. Significant relationships were rarely found for total richness due to contrasting trends of native and alien richness with species abundance. In contrast to natives, an increase in the abundance of an alien species revealed more frequent negative relationships with native richness and positive correlations with alien richness. 4. The relationship with species abundance found for native and alien components of richness differed between grasslands and woodlands. While we found putative support for negative impacts on native richness for several alien species in grasslands, the similar negative correlations in woodlands were more likely to reflect the shade intolerance of alien grasses where native species richness was high. 5. Synthesis. Our analyses reveal that widespread alien and native species play different roles in the plant communities in which they co-occur. Separately analysing the relationship with species abundance for alien and native components of richness can help distinguish between situations where aliens may be acting as the primary drivers in plant community changes or simply passengers. This is an essential first step in designing further experimental studies to determine the underlying ecological processes and potential ecosystem impacts of alien species. [ABSTRACT FROM AUTHOR]

Copyright of Contributii Botanice is the property of Contributii Botanice and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Torrential rains (in January 2011) that have swept a limited area in the Eastern Desert, facing Assiut Province (Upper Egypt), resulted in enriching the vegetation in Wadi Al-Assiuty and its tributary Wadi Habib. Vegetation survey carried out shortly after this event (in May) revealed the prevalence of annuals which are hardly recognizable in such usually dry habitats. The normally scarce perennial vegetation has flourished. A total of 66 plant species, 33 perennials and 33 annuals, belonging to 53 genera from 22 different families were recorded. Therophytes are the predominant life form (50%) followed by chamaephytes (21%), phanerophytes (15%), hemicryptophytes (11%) and geophytes (3%). Chorological analysis revealed that Saharo-Arabian (81.8%) constitute the main bulk of the total flora of the studied area. The majority of the perennial species behave similarly to each other in their phenology, and usually perennials sprout at the end of February, become leafy in March, flower in April and produce fruits between April and July. The investigation revealed that the wadis studied are potential shelters of four vegetation groups. Twenty two of the recorded species (33.3%) are omnipresent and had a dominant degree of occurrence (Q-value ⩾ 0.2). The highest among others were Zilla spinosa and Zygophyllum coccineum which recorded in 86% and 88% respectively of the studied stands and spread their dominancy all over the Eastern Desert of Egypt. [ABSTRACT FROM AUTHOR]

This paper presents a syntaxonomical revision and statistical determination of diagnostic, constant and dominant species of higher syntaxa of Poland based on relevés stored in the Polish Vegetation Database. All the analyses were performed on a data set consisting of 43,686 relevés containing 2,853 species of vascular plants, bryophytes, algae and lichenized fungi. The data set was subjected to formalized and hierarchical classification, which revealed 44 classes and 153 alliances. The vegetation of Poland is divided into the classes: Zosteretea marinae, Charetea, Elyno-Seslerietea, Violetea calaminariae, Stellarietea mediae, Cakiletea maritimae, Salicetea herbaceae, Isoëto-Nano-Juncetea, Oxycocco-Sphagnetea, Ammophiletea arenariae, Potametea, Thero-Salicornietea, Carici- Kobresietea, Festuco-Puccinellietea, Erico-Pinetea, Juncetea trifidi, Loiseleurio-Vaccinietea, Lemnetea, Quercetea pubescentis, Littorielletea uniflofae, Koelerio-Corynephoretea, Rosopendulinae-Pinetea mugo, Cymbalario-Parietarietea, Bidentetea tripartitae,Alnetea glutinosae, Scheuchzerio-Caricetea, Robinietea, Montio-Cardaminetea, Thlaspietea rotundifolii, Festuco-Brometea, Salicetea purpureae, Molinio-Arrhenatheretea, Mulgedio-Aconitetea, Carpino- Fagetea, Calluno-Ulicetea, Quercetea robori-petraeae, Vaccinio-Piceetea, Polygono arenastri-Poëtea, Asplenietea trichomanis, Phragmito-Magno-Caricetea,Artemisietea vulgaris, Epilobietea angustifolii, Galio-Urticetea, Rhamno- Prunetea. In order to determine a diagnostic species for alliances and classes, statistical measures of fidelity were used. A revised list of vegetation units of Poland is presented. [ABSTRACT FROM AUTHOR]

Subsidence ponds are a characteristic and numerous feature in southeast Northumberland, forming over coal mine works. Their wildlife remains poorly recorded. This paper presents data on the plant communities from 20 subsidence ponds in fields at Blakemoor Farm at the southern end of Druridge Bay. Plants were surveyed in the summer of 2012 to characterise the communities, using the National Vegetation Classification (NVC). Ponds ranged from the permanent and well vegetated to ephemeral tyre ruts. Thirteen NVC communities were identified, primarily "Open Vegetation" and "Swamp" communities dominated by emergent species or plants of disturbed, occasionally flooded land. The subsidence ponds therefore create habitat for some temporary and shallow-water plant communities which are not represented in permanent, deeper ponds. No non-native species were found in the subsidence ponds, their inaccessibility on farm land perhaps a barrier to infestation. In addition the origin of the ponds represents a form of cultural biodiversity in the landscape linking back to the coal mining economy of the region. [ABSTRACT FROM AUTHOR]

Tree communities of secondary deciduous oak forests were surveyed in 13 forests (two in residential and 11 in rural areas) in the warm temperate Hokuriku District of Japan to understand the effects of fragmentation, location (residential or rural), and logging history. The rural forest logged most recently, where diameter at breast height was smallest, had a distinct canopy tree (>12 m) community due to an increase of trees from wind-dispersed seeds. The rural forest with gaps and the two residential forests also had different canopy tree communities from the other rural forests. In contrast, the tree community in the shrub layer (≤6 m) was not influenced by logging history and the existence of gaps but by location only. This was caused by an increase in evergreen trees (consequently causing poor light conditions on the forest floor) and a decrease in trees from wind-dispersed seeds in the residential forests. Among the rural forest patches, no negative effects of forest size and isolation on density of tree individuals were detected for any seed dispersal mode. This may be because many forest patches were arranged at distances of 10-50 m from neighboring patches in rural areas, which enables tree species with low dispersal ability to disperse their seeds to neighboring forests. However, as found in the residential forests, long-term abandonment and extensive fragmentation may gradually reduce tree diversity through loss of tree species with shade intolerance and low seed dispersal ability. [ABSTRACT FROM AUTHOR]

Abstract: The influence of organisms on pedogenesis is acknowledged in the scorpan model; however organisms, plants in particular, might be seen in a different light within the scorpan model. In fact, in minimally managed terrestrial ecosystems, biota coexists with soil as part of a feedback system, in which the biota not only influences soil development, but is also in turn influenced by it. This means that in natural environments a particular soil is usually associated with a typical combination of plant species which thrive in the biotope defined by the soil physical and chemical properties. Changes in soil features will favor certain species over others, thus modifying the structure of the resident plant communities. This makes plant communities very effective proxies of soil properties, effectively acting as widespread biological sensors. In this paper we will show how plant communities can be utilized to improve the quality of digital soil maps, effectively reducing the amount of field work needed by soil surveys, through a combination of relatively swifter and cheaper vegetation surveys and remote sensing data. The approach we propose is based on the spectral and textural properties of plant communities which can be summarized from high resolution remotely sensed images and LIDAR data through the use of geostatistical, spectral and geomorphometric descriptors. These descriptors are then associated with the scores obtained from the ordination of the plant communities'' relative coverage. Ordination projects the high dimensional plant cover data into a lesser dimensional space, thus making easier to establish a relation between ecological space and geostatistical descriptors. Once established this relation can be exploited through the use of regression techniques in a regression kriging framework. In this case study, we applied the proposed model to the prediction of soil organic carbon content in an alpine grassland. The use of plant communities cover almost doubled the predictive power of the model from an R 2 of 0.32 to an R 2 of 0.66 in cross-validation, a result which strongly advocates for the efficiency of the proposed approach. [Copyright &y& Elsevier]

Abstract: This study was carried out on the transported bed soil dredged from the outlet of Lake Burullus to the Mediterranean Sea and deposited nearby, forming by this way new land that underwent a primary plant succession. The multi-methodological approach comprised floristic inventories, vegetation sampling and soil composition analyses of the study site in order to detect the crucial parameters controlling the plant resettlement on recently deposited soil as related to time, local micro-topography and substrate characteristics. Floristic composition was assessed for the first 10 years of primary succession (2001–2010) on 18 stands of the area, distributed on basement, slope stands and plateau of the landfill, respectively. Vegetation surveys were the basis of multivariate analyses of the vegetation and soil data using TWINSPAN, DCA and CCA. Relationships between the edaphic gradients, floristic composition and species diversity were assessed. Forty-one species were identified (22 annuals and 19 perennials) after ten years development compared with 7 species at the first year. After application of TWINSPAN and DCA on the data of the first year of establishment, two simple vegetation groups were recognized and named after their dominant species, Senecio glaucus and Bassia indica. In comparison, the multivariate analysis of the last year (i.e. after 10 years of succession) led to identify 4 more advanced vegetation groups: Senecio glaucus–Cakile maritima–Zygophyllum album, Bassia indica–Mesembryanthemum nodiflorum, Arthrocnemum macrostachyum and Phragmites australis–Limbarda crithmoides. These plant communities are comparable to the other communities in the same region, showing the tendency to establish the climax vegetation of Mediterranean coastal areas. The notable edaphic variables that affect the succession of the vegetation groups in the study area were moisture, salinity, organic matter, minerals (Ca, Na, K, Cl, SO4), soil texture and human disturbance. [Copyright &y& Elsevier]

This study was designed to investigate non-point source nutrient pollution and its influences on submerged aquatic plant community structure and biological invasion in the Weeks Bay National Estuarine Research Reserve (WBNERR). A monthly vegetation survey was conducted to document plant abundance and changes in community structure; physicochemical data and water samples were collected on a bi-monthly basis to monitor environmental conditions (i.e., pH, salinity, dissolved oxygen, light intensity, and attenuation) and water column nutrient (NO/NO and NH) and chlorophyll a concentrations. A total of seven submerged aquatic species were identified at the WBNERR with the occurrence of only one non-native species ( Hydrilla verticillata). Statistical analyses suggest that water column nitrogen concentrations along with variations in dissolved oxygen (0.6-11.5 mg L), light attenuation, pH (5.6-8.6), and temperature (11-33°C) play key roles in determining the aquatic plant abundance and distribution in the WBNERR. [ABSTRACT FROM AUTHOR]

Abstract: A survey of land taken out of production from the early 1990s onwards under the European Union''s set-aside policy in England was carried out in 2008, to record plant communities in set-aside of different ages, effects of distance from the field edge, sowing and soil type. Communities were classified using the Countryside Vegetation System (CVS), Ellenberg indicators and Grime CSR strategy. Species richness declined with distance from the field boundary. Annuals declined with age of set-aside. In older set-aside, perennials dominated, 40–50% of species were grasses, and grasses covered over 70% of the area. Sown areas had a higher proportion of grass species and a lower proportion of wind-dispersed species. Perennial forbs increased over time in naturally regenerated swards but decreased on sown swards. Annuals and grasses were more prevalent on light soils, with more bare ground on heavy soils. Most transects fell into CVS aggregate classes ‘tall grassland/herb’ and ‘fertile grassland’. Ellenberg fertility values decreased initially but then stabilised. Competitor scores increased, and ruderal scores declined, with age. In general, the rate of change declined with age. Although few sites had plant communities of significant conservation interest, the value of set-aside is likely to be primarily to maintain botanical diversity in intensively farmed areas, as well as providing food and habitat for fauna. [Copyright &y& Elsevier]

The aim of this study is to present a phytosociological survey of the Italian Alnus glutinosa-dominated swamps (Alnion glutinosae). The analysis highlights the occurrence of the following associations: Corno hungaricae-Alnetum glutinosae and Carici elatae-Alnetum glutinosae (northern Italy), Hydrocotylo-Alnetum glutinosae and Scrophulario umbrosae-Alnetum glutinosae (central and southern Italy). Carici elongatae-Alnetum glutinosae, which is widely distributed in central and northern Europe, has so far only been identified in a narrow area of the western continental sector of the Po plain; elsewhere, this association is replaced by communities generally characterized both by the lower expression of species whose main center of distribution is in the central-northern sector of Europe, and by the presence of differential entities. The comparison of data from southern, central and northern Europe confirms the syntaxonomic autonomy of most of the Italian Black Alder swamps. Moreover, the study reveals the existence of a north-to-south phytogeographic gradient, according to which the sub-boreal phytocoenoses are gradually being replaced by the central-European temperate communities as well as by the last southern European phytocoenoses occurring in the temperate and Submediterranean/Mediterranean contexts. [ABSTRACT FROM PUBLISHER]

We report on phytosociological survey of the forests dominated by Pinus contorta var. contorta and/or Picea sitchensis that thrive on the Pacific Northwest, between the Strait of Juan de Fuca in Washington and Cape Mendocino in northwestern California. Through tabular and average linkage cluster analyses, 198 relevés taken at 69 sites were classified. Diagnostic tables, climatic, edaphic, and biogeographical data were used to establish floristic affinities among the seven identified associations and to interpret their distributions in psammophilous and zonal gradients, as well as their syntaxonomic position in the Temperate North American class Tsugetea mertensiano-heterophyllae. Four associations are described here for the first time: Arctostaphylo uva-ursi-Pinetum contortae, Carici obnuptae-Pinetum contortae, Morello californicae-Piceetum sitchensis, and Pseudotsugo menziesii-Pinetum contortae. [ABSTRACT FROM PUBLISHER]

A botanical survey has been conducted to determine the influence of invasive species on the main indigenous communities in the Spanish Mediterranean coast and evaluate the current status of these communities in the eastern coast of Spain. The work was done in about 35 km of coastline located in Valencia (Spain). A total of 361 species cataloged are present in the study area, belonging to 79 different families. 49 of them have been inventoried invasive species which currently affect 38 plant communities. For this cause, we have developed a map of location finding out the area occupied by the same at every point and key to indigenous communities it affects. The plant communities characteristic of semi-mobile dunes Centaureo maritimae-Echietum sabulicolae and Medicagini marinae-Ammophiletum australis have turned out to have a greater degree of invasion. Carpobrotus edulis, Agave americana, Arundo donax, Oxalis pes-caprae and Cortaderia sellowiana are invasive species that cause further encroachment, both in area as a number of vegetation communities they affect. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stylisma pickeringii var. pattersonii (Convolvulaceae) is endangered in Illinois and Iowa, and occurs in scattered populations in other states. During 1999 and 2000, two insect species previously unreported from Illinois were observed visiting its flowers. This study was undertaken to survey additional insect visitors, as well as to characterize the plant community where S. pickeringii occurs. The objectives were to survey: 1) floral traits (anthesis and flower density) of S. pickeringii, 2) associated plant species, and 3) insect visitor characteristics. Floral traits were determined and associated plant species surveyed in Mason County (degraded hay field on private property) and Henderson County (dry sand prairie at the Big River State Forest), Illinois. Insects visiting flowers were collected at 10:00 a.m., 12:30 p.m., and 3:00 p.m. during June, July, and August in 2001 and 2002. Individual flowers lasted one day and remained open for 6-8 hours. Peak flowering occurred from early to the middle of July when S. pickeringii was the dominant species in flower. Henderson County contained a greater diversity of native plant species with less bare ground and fewer non-native species than the Mason County site. Forty-seven insect species were observed visiting S. pickeringii flowers. Most frequent visitors were Apis mellifera (Hymenoptera: Apidae), Bombylius fraudulentus (Diptera: Bombyliidae), and Heterostylum croceum (Diptera: Bombliidae). The diversity of visiting insects was higher earlier than later in the day, in July and August than June, and in Henderson than Mason County. [ABSTRACT FROM AUTHOR]

The line-point transect method has been used to estimate plant cover for about nine decades. In particular, the method is often used to determine baseline plant cover and monitor for changes in plant cover over time. In such cases, detection of change requires both the initial transect starting position and angle of orientation are exact in relocation without error. A study was conducted on influences of errors in basal cover estimates that resulted from inexact relocation and orientation of a resample transect. Simulation studies of actual field data showed that variation in plant cover estimates from relocated line-point transects increased with each source of error and combinations of these errors. Relocated transects resulted in unbiased estimates of total-plant cover only when means over all transects are used to detect changes over time. Substantial errors were observed when the mean cover of individually relocated transect was compared to its original transect. [ABSTRACT FROM AUTHOR]

A vegetation survey was carried out in a relatively intact Atlantic blanket bog in Southwest Ireland to study the vegetation patterns in relation to environmental variation, and to quantify the effect of artificial and natural borders on compositional variation. The data were analysed using canonical correspondence analysis. In terms of both vegetation and water chemistry, the study site can be categorized as typical of Atlantic blanket bogs in the maritime regions of North-western Europe. The distribution of plant species was explained mainly by depth of the water table. The distribution of bryophytes was secondarily explained by the pH of the bog water, while the distribution of vascular plants was secondarily explained by concentrations of ammonia. The vegetation distribution exhibited little variation between the central sector of the peatland and its disturbed edges (hill-grazing and restoration areas), but a substantial variation was observed between the area along a natural edge (stream) and the areas close to the other peatland borders or centre. Similarly, the internal variation within each sector (centre, hill-grazing edge and restoration area edge) was small, but substantial vegetation variation was observed within the area located along the stream. The area along the stream was associated with relatively deep water table, shallow peat depth, high water colour, pH and NH4 + concentrations, and low Cl¿ concentrations in the bog water. Our results suggest the existence of strong centre-natural margin gradients, as in raised bogs, and indicate that human or animal disturbance do not give rise to the marked transition zones that often characterize natural margins of mire systems. This indicates that even small areas and remnants of Atlantic blanket bogs are worthy of conservation and that their conservation value would benefit from the inclusion of sectors close to the natural peatland borders, which would increase the plant biodiversity of the conserved area. [ABSTRACT FROM AUTHOR]

The article presents the phyto-sociological and entomological surveys conducted to determine the impact of anthropisation on the local vegetation and abundance of tsetse in southern Burkina Faso. The survey aims to compare the diversity and densities of this species in protected and non protected areas using the transects from the river bank to savannah and detailing the phytological description of all trapping sites. The scheme shows that there is great vegetation homogeneity between transects and heterogeneity in savannah. The protected and non protected areas also have significant difference in the densities of tsetse.

Through tabular and average linkage cluster analyses, 737 phytosociological relevés were classified. Based on these relevés, we described and typified the associations, alliances, orders, and classes grouping the coastal plant communities of the Baja California peninsula. Diagnostic tables, classification by average linkage clustering, and climatic, edaphic, and biogeographical data were used to establish floristic affinities among these syntaxa and to interpret their distributions. Syntaxa were characterized by their floristic composition, physiognomy, and biogeographical distribution, along with their positions in halophilous and psammophilous gradients. Thirty-three associations were identified, of which 22 are here described for the first time. Our syntaxonomical proposal includes descriptions of nine new alliances, seven new orders and four new classes: Allenrolfeetea occidentalis, Atriplici julaceae–Frankenietea palmeri, Euphorbio leucophyllae–Sporoboletea virginici and Achyronichio cooperi–Abronietea villosae. [ABSTRACT FROM AUTHOR]

Great Smoky Mountains National Park (GSMNP) contains one of the most diverse assemblages of vegetation communities in North America. Over 70 unique community associations comprised of over 1300 native plant species have been identified in the Park. This wide array of communities provides habitat for unknown multitudes of other taxa whose abundance, distribution, and ecological importance remain largely unknown. The All Taxa Biodiversity Inventory (ATBI) underway in the Park is the first comprehensive attempt to better understand the vast array of species present in the Park. This paper discusses the composition, structure, distribution, and extent of vegetation communities in GSMNP. Detailed assessments of the vegetation, site, and soil characteristics of the 19 ATBI plots are also included. [ABSTRACT FROM AUTHOR]

Vegetation structure diversity between different plant communities has been shown to influence birds. We conducted this study to determine whether the diversity in vegetation structure in similar plant communities, due to land-use, had an effect on birds. Bird and vegetation surveys were conducted on four different land-use types in the Kalahari thornveld area of the North West Province of South Africa, and analysed using regression and multivariate analysis. Variations in vegetation structure because of land-use types showed a significant correlation with bird species diversity. Although seasonal changes were also shown to have an effect, the nonmetric multidimensional scaling plots of bird species diversity and vegetation structure showed similar relative positions. Résumé On a montré que la diversité de la structure de la végétation de différentes communautés de plantes influence les oiseaux. Nous avons mené cette étude pour déterminer si, dans des communautés de plantes semblables, la diversité de la structure de la végétation due à l'utilisation des sols avait aussi un effet sur les oiseaux. Les études des oiseaux et de la végétation ont été réalisées avec quatre types d'utilisation des sols différents dans la région broussailleuse du Kalahari dans la North West Province, en Afrique du Sud, en utilisant des analyses de régression et multivariées. Les variations de la structure de la végétation dues aux types d'utilisation des sols ont montré une corrélation significative avec la diversité des espèces d'oiseaux. Bien que les changements saisonniers aient aussi eu un effet visible, les plots de positionnement multidimensionnel non métrique de la diversité des espèces d'oiseaux et de la structure de la végétation ont montré des positions relatives similaires. [ABSTRACT FROM AUTHOR]

Questions: Is change in cover of dominant species driving the velocity of succession or is it species turnover (1)? Is the length of the time-step chosen in sampling affecting our recognition of the long-term rate of change (2)? Location: 74 permanent plots located in the Swiss National Park, SE Switzerland, ca. 1900 m a.s.1. Methods: We superimpose several time-series from permanent plots to one single series solely based on compositional dissimilarity. As shown earlier (Wildi & Schütz 2000) this results in a synthetic series covering about 400 to 650 yr length. Continuous power transformation of cover-percentage scores is used to test if the dominance or the presence-absence of species is governing secondary succession from pasture to forest. The effect of time step length is tested by sub-samples of the time series. Results: Altering the weight of presence-absence versus dominance of species affects the emerging time frame, while altering time step length is uncritical. Where species turnover is fast, different performance scales yield similar results. When cover change in dominant species prevails, the solutions vary considerably. Ordinations reveal that the synthetic time series seek for shortest paths of the temporal pattern whereas in the real system longer lasting alternatives exist. Conclusions: Superimposing time series differs from the classical space-for-time substitution approach. It is a computation-based method to investigate temporal patterns of hundreds of years fitting between direct monitoring (usually limited to decades) and the analysis of proxy-data (for time spans of thousands of years and more). [ABSTRACT FROM AUTHOR]

As cities grow, they usually spread out into their rural surroundings. Until the 19th century, the original natural vegetation in these surroundings was seldom looked upon as a resource to be preserved within cities. But in the late 20th century, interest in preservation of natural vegetation as part of the future green infrastructure in cities has increased in many countries. The aim of this paper is to study interconnections between researchers carrying out work in this field. The method used was a survey of published items and analysis of how the references in these papers indicated communication, or lack of communication, between the researchers up to 2004. Scientific papers numbering 153 were found from 21 countries, mainly from two groups of researchers based i) in the USA and Australia, and ii) in the Nordic countries, especially Finland and Sweden. A lack of communication between the two research groups was found. References from Nordic research to Australian and American papers and vice versa were almost absent. The two groups seem to have studied the same field of research with little or no reference to each other. Possible explanations for this situation are discussed. A lack of common terminology has been an obstacle and searching in databases has thus been obstructed. [ABSTRACT FROM AUTHOR]

A botanical survey of the vascular flora of Hamilton County, Iowa was conducted from 2001 to 2004. During this survey 973 taxa (761 native) were encountered. A search of the literature and a survey of Iowa State University's Ada Hayden Herbarium for additional documented specimens added 28 taxa to the flora. This total of 1001 taxa places Hamilton County fourth in vascular plant richness among inventories conducted in Iowa since 1950. A checklist including common names of most taxa, habitat and abundance data for all taxa encountered during the current survey is presented. Information on earlier collections includes source, and if based on a herbarium voucher, the date of the voucher collection. This study reports 12 new taxa that are not included in Eilers and Roosa's (1994) checklist of the Iowa vascular flora. Fourteen species found during this inventory are included in the 2002 Iowa Natural Resource Commission list of endangered, threatened, or special concern species. Sites containing significant plant taxa in the survey area are mapped and the notable plant taxa for each of these sites are listed. The results of this survey provide a more thorough understanding of the flora in Hamilton County and in Iowa. These results are also important to conservation efforts such as habitat restoration and reconstruction, and in evaluating the habitat and abundance status of the vascular flora in Hamilton County and the state. This inventory exemplifies the need for similar extensive studies of the flora of other counties in Iowa. The development of a continuously maintained computer database of information on voucher specimens in the herbaria of Iowa would be an invaluable aid for conducting these studies. [ABSTRACT FROM AUTHOR]

The vegetation and plant communities of the Emiquon Preserve, Fulton County, Illinois, were studied during the 2003-2004 growing seasons. A total of 395 vascular plant taxa were found; 8 fern and fern-allies, 1 gymnosperm, 99 monocots, and 287 dicots. Overstory and ground layer composition and structure were examined in three second growth forest communities. In the willow zone of the floodplain, tree densities averaged 1192 stems/ha with a basal area of 27.486 m²/ha, Salix nigra Marsh. (black willow) being the leading dominant. In the maple zone of the floodplain, tree densities averaged 506 stems/ha with a basal area of 49.191 m²/ha, Acer saccharinum Marsh. (silver maple) being the leading dominant. In the upland forest, Robinia pseudoacacia L. (black locust) dominated with an IV of 112 (possible 200), followed by Gleditsia triacanthos L. (honey locust), and Fraxinus lanceolata Borkh. (green ash). In this forest, tree densities averaged 672 stems/ha with a basal area of 33.628 m²/ha. [ABSTRACT FROM AUTHOR]

In the Midwest, the oak savanna is a unique plant community located between the western prairies and northern forests, but, once the most common plant community in Wisconsin, it is now one of the region's rarest plant communities. To assess the success of varying intensities of management practices, standard dendrochronology and vegetation surveying methods were used to determine the age structure and species composition in oak savanna sites that varied from intensely managed to unmanaged. Size and age distributions revealed that the number of distinct cohorts of oaks increased in less managed sites. Seedlings and saplings were present in high frequencies in all sites; however, management practices such as fire applications that were too frequent apparently decreased oak survivorship, as did the competition in the closed canopies of the unman- aged sites. A fire frequency of 2-3 years eliminates competition, but a frequency of 4-6 years, typical of fire-adapted forest communities, allows for slower-growing species and younger oaks to survive, while still maintaining a low density. In these conditions, where growth rates vary in time, the use of dendrochronology is necessary to obtain an accurate canopy structure for fire-adapted forest communities. Quercus macrocarpa was dominant in the more managed sites, but shade-tolerant species were dominant in the unmanaged site. At present, the canopy composition in the managed sites represented an oak savanna assemblage; however, the unmanaged composition was shifting to a woodland assemblage. Thus, remnant oak savanna can be over- or under-managed, and unmanaged oak savanna can be overlooked as woodlands. [ABSTRACT FROM AUTHOR]

A detailed vegetation survey, describing floristic, structural and environmental features of 99 quadrates within a study area in the Fynbos Biome was completed. Various methods of vegetation survey were used to map and describe plant communities. These results were used to determine the feasibility of Landsat Thematic Mapper (TM) imagery to detect the plant communities and therefore the possibility to serve as an operational monitoring tool for coastal lowland fynbos. Principal component analysis (PCA) was applied to seven years' TM imagery as a method of data compression, whereby a statistical abstraction of the variability inherent in the original band sets was created and noise discarded. In this way representative imagery of several years' data were combined to serve as a baseline against which plant community change can be measured. Two supervised maximum likelihood classifications were done using this representative and a single year's (1997) imagery. Classification accuracy is based on the agreement between the classified imagery and compares favourably with field vegetation survey results. There is also a classification improvement between the single year's imagery and the combined imagery using PCA, therefore confirming the effective use of PCA to reduce noise and to obtain baseline imagery for monitoring purposes in coastal lowland fynbos. [ABSTRACT FROM AUTHOR]

As an introduction to the special issue "Vegetation of Circumboreal Coniferous Forests", a brief history is provided of the development and present state of floristic vegetation surveys of the boreal and mountain coniferous forests of Europe, northern Asia and North America. The focus is on forests assigned to the phytosociological class Vaccinio-Piceetea and closely related vegetation types. [ABSTRACT FROM AUTHOR]

Discusses the consequences and implications of two basic methodological choices in wildland vegetation inventories. Collection of data; Accuracy with which vegetation inventories predict plant community production; Implications for the design of practical, extensive survey methods for wildland vegetation.

The article discusses potential applications of radar in agricultural surveys, in mapping natural vegetation, and in forest surveys. It is stated that side-looking airborne radar (SLAR) will undoubtedly receive most application in plant geography and ecology studies. The images produced by such a radar look similar to a continuous strip photograph taken from a very high altitude. The self-illuminating feature of radar help measuring distance and relative velocity by measuring travel time for the radar wave and Doppler frequency shift of this wave. A study done in the Horsefly Mountain area has values of applying multiple polarization for aiding discrimination of plant communities.

The article presents a detailed phytosociological analysis of the savanna vegetation of the Venezuelan Llanos. The analysis aims to acquire a precise knowledge of the internal variability of vegetation and of the environmental factors involved and to test different methods of vegetation analysis in order to select that most appropriate for this type of vegetation. The association-analysis method was used and the Biological Station of Los Llanos was chosen for this study because it is a protected stand of vegetation exclusively used for research purposes. A brief outline of the entire inland plain region of Venezuela and its main vegetation and climatic characteristics as well as the significance of the particular type of savanna chosen for the analysis is presented.