The Efficacy and Ecological Impacts of Herbicide and Cutting Regimes on the Submerged Plant Communities of Four British Rivers. II. A Multivariate Analysis of the Effects of Management Regimes on Macrophyte Communities

1990 ◽  
Vol 27 (2) ◽  
pp. 541 ◽  
Author(s):  
A. M. Fox ◽  
K. J. Murphy
Keyword(s):  
Multivariate Analysis ◽  
Plant Communities ◽  
Ecological Impacts ◽  
Submerged Plant ◽  
Macrophyte Communities ◽  
Management Regimes ◽  
Cutting Regimes

Sur l'organisation phytochimique de formations prairiales permanentes

2001 ◽  
Vol 79 (4) ◽  
pp. 510-519 ◽  
Author(s):  
Philippe Lebreton ◽  
Bernard Jeangros ◽  
Christiane Gallet ◽  
Jan Scehovic
Keyword(s):  
Cell Wall ◽  
Multivariate Analysis ◽  
Plant Communities ◽  
Nutrient Pool ◽  
Grassland Species ◽  
Anthriscus Sylvestris ◽  
Cool Environment ◽  
Mineral Components ◽  
Herbaceous Community ◽  
Food Value

Organic and mineral components have been analysed on 18 dicotyledonous species of permanent grassland communities. Multivariate analysis revealed an opposition between a macromolecular pool (cellulose and lignin) and a nutrient pool (potassium and phosphorus, nitrogen). The first pole is characterized by Tragopogon pratensis L. (Compositae) and Galium mollugo L. (Rubiaceae), the second by Anthriscus sylvestris (L.) Hoffm. (Umbelliferae) and Geranium sylvaticum L. (Geraniaceae). The most thermo-helio-xerophilous species (Knautia arvensis (L.) Coult and Tragopogon pratensis) belong to the first group, whereas the second group includes the cool-environment species (like Alchemilla xanthochlora Roth.), which reveals an ecophysiological determinism. Moreover, correlations between the biochemical and ecological structure, and other interrelated parameters, including sclerophylly, have been shown. Compared to lignous and sempervirent plant communities, the grassland species have lower phenolic and lignin contents but higher glucide and nutrient (potassium and phosphorus) contents, which is in accordance with their food value. For this herbaceous community, the C/N ratio indicates the same general equilibrium between cell-wall macromolecules and nitrogen than for two other plant communities (mainly ligneous) previously studied, with some differences revealing distinct trends from the same general metabolic sheme.Key words: dicotyledonous plant communities, biochemical organization, C/N ratio, ecophysiology.

scholarly journals Plant communities of the class Charetea Fukarek ex Krausch 1964 in Ukraine: an overview

2012 ◽  
Vol 25 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Dmytro Iakushenko ◽  
Olena Borysova
Keyword(s):  
Plant Communities ◽  
Submerged Plant ◽  
Phytosociological Relevés ◽  
First Time

Abstract The paper presents the results of the first syntaxonomical survey of the submerged plant communities belonging to the class of Charetea Fukarek ex Krausch 1964 in Ukraine based on the interpretation of about 80 published and unpublished phytosociological relevEs. Fourteen associations of two alliances and one order are characterized briefly. The diversity of charophyte communities in Ukraine is also described in brief. A preliminary prodromus of charophyte communities in Ukraine is given. Associations of Charetum intermediae (Corillion 1957) Fija≥kowski 1960, Charetum rudis Dπmbska 1966, Nitelletumgracilis Corillion 1957 are indicated for Ukraine for the first time.

scholarly journals Hurricane Effects on a Shallow Lake Ecosystem and Its Response to a Controlled Manipulation of Water Level

2001 ◽  
Vol 1 ◽  
pp. 44-70 ◽  
Author(s):  
Karl E. Havens ◽  
Kang-Ren Jin ◽  
Andrew J. Rodusky ◽  
Bruce Sharfstein ◽  
Mark A. Brady ◽  
...  
Keyword(s):  
Water Quality ◽  
Plant Communities ◽  
Large Scale ◽  
Growing Season ◽  
Water Levels ◽  
Surface Elevation ◽  
Submerged Plant ◽  
Lake Surface ◽  
The South ◽  
Water Depths

In order to reverse the damage to aquatic plant communities caused by multiple years of high water levels in Lake Okeechobee, Florida (U.S.), the Governing Board of the South Florida Water Management District (SFWMD) authorized a "managed recession" to substantially lower the surface elevation of the lake in spring 2000. The operation was intended to achieve lower water levels for at least 8 weeks during the summer growing season, and was predicted to result in a large-scale recovery of submerged vascular plants. We treated this operation as a whole ecosystem experiment, and assessed ecological responses using data from an existing network of water quality and submerged plant monitoring sites. As a result of large-scale discharges of water from the lake, coupled with losses to evaporation and to water supply deliveries to agriculture and other regional users, the lake surface elevation receded by approximately 1 m between April and June. Water depths in shoreline areas that historically supported submerged plant communities declined from near 1.5 m to below 0.5 m. Low water levels persisted for the entire summer. Despite shallow depths, the initial response (in June 2000) of submerged plants was very limited and water remained highly turbid (due at first to abiotic seston and later to phytoplankton blooms). Turbidity decreased in July and the biomass of plants increased. However, submerged plant biomass did not exceed levels observed during summer 1999 (when water depths were greater) until August. Furthermore, a vascular plant-dominated assemblage (Vallisnera, Potamogeton, and Hydrilla) that occurred in 1999 was replaced with a community of nearly 98% Chara spp. (a macro-alga) in 2000. Hence, the lake’s submerged plant community appeared to revert to an earlier successional stage despite what appeared to be better conditions for growth. To explain this unexpected response, we evaluated the impacts that Hurricane Irene may have had on the lake in the previous autumn. In mid-October 1999, this category 1 hurricane passed just to the south of the lake, with wind velocities over the lake surface reaching 90 km h-1 at their peak. Output from a three-dimensional hydrodynamic / sediment transport model indicates that during the storm, current velocities in surface waters of the lake increased from near 5 cm s-1to as high as 100 cm s-1. These strong velocities were associated with large-scale uplifting and horizontal transport of fine-grained sediments from the lake bottom. Water quality data collected after the storm confirmed that the hurricane resulted in lake-wide nutrient and suspended solids concentrations far in excess of those previously documented for a 10-year data set. These conditions persisted through the winter months and may have negatively impacted plants that remained in the lake at the end of the 1999 growing season. The results demonstrate that in shallow lakes, unpredictable external forces, such as hurricanes, can play a major role in ecosystem dynamics. In regions where these events are common (e.g., the tropics and subtropics), consideration should be given to how they might affect long-term lake management programs.

scholarly journals The distribution and the habitat of submerged plant communities in river floodplain backwaters of the Ibi River.

2016 ◽  
Vol 19 (1) ◽  
pp. 55-65
Author(s):  
Koji KATAGIRI ◽  
Shigeru IKEDA ◽  
Tetsuya OISHI ◽  
Yuichi KAYABA
Keyword(s):  
Plant Communities ◽  
Submerged Plant ◽  
River Floodplain

scholarly journals A phytosociological analysis and synopsis of the dry woodlands and succulent vegetation of the Peruvian Andes

2016 ◽  
Vol 88 (suppl 1) ◽  
pp. 689-703 ◽  
Author(s):  
ANTONIO GALÁN-DE-MERA ◽  
ISIDORO SÁNCHEZ-VEGA ◽  
ELIANA LINARES-PEREA ◽  
JOSÉ CAMPOS ◽  
JUAN MONTOYA ◽  
...  
Keyword(s):  
Multivariate Analysis ◽  
Plant Communities ◽  
Sandy Soils ◽  
Dry Forest ◽  
The Other ◽  
Humboldt Current ◽  
Peruvian Andes ◽  
New Associations ◽  
Coastal Desert

ABSTRACT A phytosociological approach to dry forest and cactus communities on the occidental slopes of the Peruvian Andes is presented in base of 164 plots carried out following the Braun-Blanquet method. From them, 52 have been made recently, and the other 112 were taken from the literature. After a multivariate analysis, using a hierarchical clustering and a detendred correspondence analysis, the Acacio-Prosopidetea class (dry forest and cactus communities, developed on soils with some edaphic humidity or precipitations derived from El Niño Current), the Opuntietea sphaericae class (cactus communities of central and southern Peru, on few stabilized rocky or sandy soils) and the Carico-Caesalpinietea class (dry forests of the Peruvian coastal desert, influenced by the maritime humidity of the cold Humboldt Current), are differentiated. Within the Acacio-Prosopidetea class, two alliances are commented: the Bursero-Prosopidion pallidae (with two new associations Loxopterygio huasanginis-Neoraimondietum arequipensis and Crotono ruiziani-Acacietum macracanthae), and the new alliance Baccharido-Jacarandion acutifoliae (with the new associations Armatocereo balsasensis-Cercidietum praecocis and Diplopterydo leiocarpae-Acacietum macracanthae). For the Opuntietea sphaericae class, the association Haageocereo versicoloris-Armatocereetum proceri (Espostoo-Neoraimondion) is described on the basis of plots from hyperarid localities of central Peru. Finally, a typological classification of the studied plant communities is given.

A Quantitative Study of Soil-Plant Relations in the Eastern Goldfields of Western Australia.

1998 ◽  
Vol 20 (1) ◽  
pp. 119 ◽  
Author(s):  
B Fergusson ◽  
AJ Graham
Keyword(s):  
Cluster Analysis ◽  
Multivariate Analysis ◽  
Plant Community ◽  
Plant Communities ◽  
Western Australia ◽  
Environmental Variables ◽  
Function Analysis ◽  
Field Site ◽  
Disturbed Areas ◽  
Exchangeable Ca

The soil and plants at a 27.4 ha field site near Kalgoorlie, Western Australia, were surveyed and analysed with multivariate statistics. Cluster analysis identified four distinct plant communities at the study site. These were: Acacia acuminata shrubland Eucalyptus gvfithsii woodland Eucalyptus salrnonophloia woodland 'Ground Covers' - areas characterised by the presence of generalist herbs, low shrubs and weeds, and the absence of dominant upper storey species. Discriminant function analysis identified site elevation and soil exchangeable Ca as the primary environmental discriminants between the plant communities. Using these two variables, sample points were classified into one of the four plant communities. The two methods of classification matched well, with classification based on the two environmental variables providing an indication of which plant community would be most likely to establish in disturbed areas. This type of information can be important to revegetation programs in the region, guiding the use of appropriate plant species under different rehabilitation conditions. Key wcrds: environmental variables, plant communities, multivariate analysis, classification, revegetation

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.

scholarly journals BASIC CHARACTERISTICS OF SUBMERGED PLANT COMMUNITIES INVADED BY CABOMBA CAROLINIANA AND ITS HABITAT IN CHINA

2004 ◽  
Vol 28 (2) ◽  
pp. 231-239
Author(s):  
YU Ming-Jian ◽  
DING Bing-Yang ◽  
YU Jian ◽  
JIN Xiao-Feng ◽  
ZHOU Hong ◽  
...  
Keyword(s):  
Plant Communities ◽  
Submerged Plant ◽  
Cabomba Caroliniana ◽  
Basic Characteristics
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