scholarly journals Effect of Protection of Mountainous Vegetation against Over-Grazing and Over-Cutting in South Sinai, Egypt

Diversity ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 113
Author(s):  
Kamal H. Shaltout ◽  
Ebrahem M. Eid ◽  
Yassin M. Al-Sodany ◽  
Selim Z. Heneidy ◽  
Salma K. Shaltout ◽  
...  
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Species Turnover ◽  
Relative Concentration ◽  
Detrended Correspondence Analysis ◽  
Vegetation Pattern ◽  
Number Of Species ◽  
Size Index ◽  
South Sinai ◽  
Line Intercept

In this study, we evaluated the species diversity, density, cover, and size index of plant species within and outside 37 enclosures in the South Sinai mountainous region (Egypt), which had been protected for six years (March 2012–March 2018) against over-grazing and over-cutting for medicinal and fuel purposes. Within and outside the enclosures, the plant species were recorded, and their density (individuals per 100 m2) and cover (cm per 100 cm) were estimated using the line-intercept method. The biovolume of each individual of each species was calculated as the average of its height and diameter. The species richness was calculated as the average number of species per enclosure, and the species turnover was calculated as the ratio between the total number of species and the species richness. The relative evenness was calculated using the Shannon–Weaver index, whereas the relative concentration of dominance was calculated using the Simpson index. Detrended correspondence analysis (DCA) was applied to ordinate the vegetation inside and outside the enclosures depending on the species cover. The unpaired t-test was applied to assess the statistically significant differences in the species density, cover, and biovolume inside and outside the enclosures. By the end of the six-year period, the vegetation pattern inside the enclosures became more or less stable, presumably because of the stopping of grazing and cutting, which also led to an increase in the plant diversity, density, and cover. In general, the protection of vegetation in South Sinai improved its diversity, density, and cover. In addition, the topographic and physiographic heterogeneity in this region results in microclimatic variations, which play a major role in governing its natural vegetation.

Organisation de la richesse et de la composition floristiques d'îles de la Méditerranée occidentale (sud-est de la France)

1998 ◽  
Vol 76 (2) ◽  
pp. 321-331 ◽  
Author(s):  
Frédéric Médail ◽  
Éric Vidal
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Plant Species ◽  
Habitat Diversity ◽  
Mediterranean Islands ◽  
Plant Dispersal ◽  
Number Of Species ◽  
Continental Islands ◽  
Species Area ◽  
Species Area Relationship

The effects of physiographic variables (area, isolation, elevation, and substrate) and habitat diversity on plant species richness and composition have been investigated on some Mediterranean islands (southeastern France). The number of species - area relationship is significant but there are more diverse vegetation patterns on smallest islands (area smaller than 3.5 ha and, ultimately, 0.2 ha). Although the species composition is positively correlated to the distance from the continent, the effect of isolation is not so obvious because of the small distance of these continental islands from the continent. Some islands nearest to shore show very different plant species composition, suggesting a nonselective plant dispersal through some narrow stretches of sea. Habitat diversity represents one of the major explanatory factors of the species richness; nevertheless, it is not possible to settle between the two hypotheses effect of habitat diversity versus effect of area per se because of the correlation between the two factors. Key words: Mediterranean islands, insular biogeography, number of species - area relationship, isolation, habitat diversity, islets.

scholarly journals Growing knowledge: an overview of Seed Plant diversity in Brazil

Rodriguésia ◽  
2015 ◽  
Vol 66 (4) ◽  
pp. 1085-1113 ◽  
Author(s):  
Daniela C. Zappi ◽  
Fabiana L. Ranzato Filardi ◽  
Paula Leitman ◽  
Vinícius C. Souza ◽  
Bruno M.T. Walter ◽  
...  
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Plant Diversity ◽  
Life Forms ◽  
Amazon Rainforest ◽  
Atlantic Rainforest ◽  
Seed Plants ◽  
Seed Plant ◽  
Number Of Species ◽  
Brazilian Biodiversity

Abstract An updated inventory of Brazilian seed plants is presented and offers important insights into the country's biodiversity. This work started in 2010, with the publication of the Plants and Fungi Catalogue, and has been updated since by more than 430 specialists working online. Brazil is home to 32,086 native Angiosperms and 23 native Gymnosperms, showing an increase of 3% in its species richness in relation to 2010. The Amazon Rainforest is the richest Brazilian biome for Gymnosperms, while the Atlantic Rainforest is the richest one for Angiosperms. There was a considerable increment in the number of species and endemism rates for biomes, except for the Amazon that showed a decrease of 2.5% of recorded endemics. However, well over half of Brazillian seed plant species (57.4%) is endemic to this territory. The proportion of life-forms varies among different biomes: trees are more expressive in the Amazon and Atlantic Rainforest biomes while herbs predominate in the Pampa, and lianas are more expressive in the Amazon, Atlantic Rainforest, and Pantanal. This compilation serves not only to quantify Brazilian biodiversity, but also to highlight areas where there information is lacking and to provide a framework for the challenge faced in conserving Brazil's unique and diverse flora.

scholarly journals Projected impacts of climate change on regional capacities for global plant species richness

2010 ◽  
Vol 277 (1692) ◽  
pp. 2271-2280 ◽  
Author(s):  
Jan Henning Sommer ◽  
Holger Kreft ◽  
Gerold Kier ◽  
Walter Jetz ◽  
Jens Mutke ◽  
...  
Keyword(s):  
Climate Change ◽  
Species Richness ◽  
Plant Species ◽  
Species Turnover ◽  
Plant Species Richness ◽  
Industrialized Countries ◽  
Intergovernmental Panel ◽  
Energy Dynamics ◽  
Arctic Regions ◽  
Business As Usual

Climate change represents a major challenge to the maintenance of global biodiversity. To date, the direction and magnitude of net changes in the global distribution of plant diversity remain elusive. We use the empirical multi-variate relationships between contemporary water-energy dynamics and other non-climatic predictor variables to model the regional capacity for plant species richness (CSR) and its projected future changes. We find that across all analysed Intergovernmental Panel on Climate Change emission scenarios, relative changes in CSR increase with increased projected temperature rise. Between now and 2100, global average CSR is projected to remain similar to today (+0.3%) under the optimistic B1/+1.8°C scenario, but to decrease significantly (−9.4%) under the ‘business as usual’ A1FI/+4.0°C scenario. Across all modelled scenarios, the magnitude and direction of CSR change are geographically highly non-uniform. While in most temperate and arctic regions, a CSR increase is expected, the projections indicate a strong decline in most tropical and subtropical regions. Countries least responsible for past and present greenhouse gas emissions are likely to incur disproportionately large future losses in CSR, whereas industrialized countries have projected moderate increases. Independent of direction, we infer that all changes in regional CSR will probably induce on-site species turnover and thereby be a threat to native floras.

scholarly journals Plant Species Richness on a Transmission Right-of-Way in Southeastern Pennsylvania, U.S. Using Integrated Vegetation Management

2008 ◽  
Vol 34 (4) ◽  
pp. 238-244
Author(s):  
Richard Yahner ◽  
Richard Yahner ◽  
Bradley Ross
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Vascular Plant ◽  
Plant Species Richness ◽  
Montgomery County ◽  
Right Of Way ◽  
Number Of Species ◽  
Border Zones ◽  
Transmission Right ◽  
Source Of Information

The Green Lane Research and Demonstration Area, Montgomery County, Pennsylvania, U.S., has been studied each year since 1987, making this 21-year-old project extremely valuable as a source of information on the effects of mechanical and herbicidal maintenance on flora and fauna along an electric transmission right-of-way (ROW). In this article, our objective was to document plant species richness among treatment units and in relation to wire and border zones on the ROW. We noted the presence of plant species from late May through mid-August in 2005 and 2006 and observed 114 vascular plant species in the ten treatment units; 35 (31%) of these species were exotic. Twenty-seven (24%) species were widespread on the ROW and seven of these (26%) were exotic. The total number of species per unit ranged from 46 (40%) species in handcut units to 57 (50%) in stem–foliage spray units. Of the total number of species, 103 (90%) and 81 (71%) occurred in wire and border zones, respectively. The number of exotic species was higher in wire zones (33 [29%]) than in border zones (22 [19%]).

Biogeographical regionalisation of Colombia: a revised area taxonomy

Phytotaxa ◽  
2021 ◽  
Vol 484 (3) ◽  
pp. 247-260
Author(s):  
CARLOS E. GONZÁLEZ-OROZCO
Keyword(s):  
Cluster Analysis ◽  
Species Richness ◽  
Plant Species ◽  
Spatial Patterns ◽  
Species Turnover ◽  
Land Plants ◽  
Geospatial Analyses ◽  
Areas Of Endemism ◽  
Biogeographic Regions ◽  
Definition Of

This study proposes a biogeographical regionalisation of Colombia based on geospatial analyses of plant species turnover and a revised area taxonomy. The spatial patterns of species turnover are calculated for 20,342 plant species in continental Colombia with distributions estimated from 271,568 georeferenced records aggregated to 414 (~50 km) grid cells across Colombia. The proposed biogeographic regions are defined by applying an agglomerative cluster analysis using a matrix of pairwise Simpson’s beta (bsim) dissimilarity values. Three main centres of species richness and 25 areas of endemism were identified across Colombia, complementing the definition of regionalisation. Biogeographical regionalisation comprises two dominions (Pacific and Boreal Brazilian), six provinces (Chocó-Darién, Guajira, Magdalena, Paramo, Sabana and Imerí) and thirty-five districts. The revised area taxonomy provides an updated and objective biogeographical classification for Colombia and is the first biogeographic regionalisation exclusively based on the taxic distributional overlap of Colombia´s land plants.

scholarly journals Fast diversification through a mosaic of evolutionary histories characterizes the endemic flora of ancient Neotropical mountains

2020 ◽  
Vol 287 (1923) ◽  
pp. 20192933 ◽  
Author(s):  
Thais N. C. Vasconcelos ◽  
Suzana Alcantara ◽  
Caroline O. Andrino ◽  
Félix Forest ◽  
Marcelo Reginato ◽  
...  
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Species Turnover ◽  
Plant Species Richness ◽  
Campo Rupestre ◽  
Population Isolation ◽  
Mountain Ranges ◽  
Extinction Rates ◽  
Speciation Rates ◽  
Endemic Flora

Mountains are among the most biodiverse areas on the globe. In young mountain ranges, exceptional plant species richness is often associated with recent and rapid radiations linked to the mountain uplift itself. In ancient mountains, however, orogeny vastly precedes the evolution of vascular plants, so species richness has been explained by species accumulation during long periods of low extinction rates. Here we evaluate these assumptions by analysing plant diversification dynamics in the campo rupestre , an ecosystem associated with pre-Cambrian mountaintops and highlands of eastern South America, areas where plant species richness and endemism are among the highest in the world. Analyses of 15 angiosperm clades show that radiations of endemics exhibit fastest rates of diversification during the last 5 Myr, a climatically unstable period. However, results from ancestral range estimations using different models disagree on the age of the earliest in situ speciation events and point to a complex floristic assembly. There is a general trend for higher diversification rates associated with these areas, but endemism may also increase or reduce extinction rates, depending on the group. Montane habitats, regardless of their geological age, may lead to boosts in speciation rates by accelerating population isolation in archipelago-like systems, circumstances that can also result in higher extinction rates and fast species turnover, misleading the age estimates of endemic lineages.

scholarly journals The effect of Agricultural Landscape Type on Field Margin Flora in South Eastern Poland

2016 ◽  
Vol 75 (2) ◽  
pp. 217-225 ◽  
Author(s):  
Małgorzata Wrzesień ◽  
Bożena Denisow
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Plant Species ◽  
Agricultural Landscape ◽  
Vascular Plant ◽  
Detrended Correspondence Analysis ◽  
Agricultural Landscapes ◽  
Plant Species Diversity ◽  
Field Margins ◽  
Landscape Type

Abstract Plant species diversity is threatened in many agricultural landscapes due to the changes it has to undergo. Although the modification of the agricultural landscape pattern is observed across Europe, both extensive and intensive agricultural landscapes still co-exist in Poland. The objective of the study was to examine the flora in field margins in intensively and extensively managed agricultural landscapes, located across three regions in SE Poland. The flora was compared with respect to species richness, diversity, and evenness indices. Detrended correspondence analysis was employed to characterise variation in species composition. Agricultural landscape type made a higher contribution than the topography or geology to species richness and composition in field margins. Field margins function as important habitats for general vascular plant species diversity and are useful for the conservation of rare, threatened, endangered or bee plants. A significant decline in species diversity was observed over a distance of 1000 m from the habitat elements. Plants growing on field margins are mainly perennials; however participation of annuals clearly increases in intensive landscapes. The participation of wind-dispersed species decreased in an open-spaced intensive landscape. Animal-dispersed plants predominated in an extensive landscape with forest islands. Irrespective of landscape type, native species predominated. However, these habitats create the biota and corridors for alien-invasive species as well.

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