scholarly journals Patterns of plant diversity and endemism in Namibia

Bothalia ◽  
2006 ◽  
Vol 36 (2) ◽  
pp. 175-189 ◽  
Author(s):  
P. Craven ◽  
P. Vorster
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Endemic Species ◽  
Distribution Patterns ◽  
The Other ◽  
Species Overlap ◽  
High Species Diversity ◽  
Total Plant ◽  
Endemic Flora ◽  
Species Being

Species richness, endemism and areas that are rich in both species and endemic species were assessed and mapped for Namibia. High species diversity corresponds with zones where species overlap. These are particularly obvious where there are altitudinal variations and in high-lying areas. The endemic flora of Namibia is rich and diverse. An estimated 16% of the total plant species in Namibia are endemic to the country. Endemics are in a wide variety of families and sixteen genera are endemic. Factors that increase the likelihood of endemism are mountains, hot deserts, diversity of substrates and microclimates. The distribution of plants endemic to Namibia was arranged in three different ways. Firstly, based on a grid count with the phytogeographic value o f the species being equal, overall endemism was mapped. Secondly, range restricted plant species were mapped individually and those with congruent distribution patterns were combined. Thirdly, localities that are important for very range-restricted species were identified. The resulting maps o f endemism and diversity were compared and found to correspond in many localities. When overall endemism is compared with overall diversity, rich localities may consist of endemic species with wide ranges. The other methods identify important localities with their own distinctive complement of species.

scholarly journals Conservation priorities and distribution patterns of vascular plant species along environmental gradients in Aberdare ranges forest

PhytoKeys ◽  
2019 ◽  
Vol 131 ◽  
pp. 91-113 ◽  
Author(s):  
Solomon Kipkoech ◽  
David Kimutai Melly ◽  
Benjamin Watuma Mwema ◽  
Geoffrey Mwachala ◽  
Paul Mutuku Musili ◽  
...  
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Endemic Species ◽  
Vascular Plant ◽  
Distribution Patterns ◽  
Partial Least Square ◽  
Least Square ◽  
Partial Least Square Regression ◽  
Conservation Priorities ◽  
Conservation And Management

Distribution patterns of biodiversity and the factors influencing them are important in conservation and management strategies of natural resources. With impending threats from increased human population and global climatic changes, there is an urgent need for a comprehensive understanding of these patterns, more so in species-rich tropical montane ecosystems where little is known about plant diversity and distribution. Vascular species richness along elevation and climatic gradients of Aberdare ranges forest were explored. A total of 1337 species in 137 families, 606 genera, 82 subspecies and 80 varieties were recorded. Correlations, simple linear regression and Partial least square regression analysis were used to assess richness and diversity patterns of total plants, herbs, shrubs, climbers, arboreal and endemic species from 2000–4000 m above sea level. Total plant species richness showed a monotonic declining relationship with elevation with richness maxima at 2000–2100 m a.s.l., while endemic species richness had a positive unimodal increase along elevation with peaks at 3600–3700 m a.s.l. Herbs, shrubs, climbers and arboreal had significant negative relationships with altitude, excluding endemism which showed positive relations. In contrast, both air and soil temperatures had positive relationships with taxa richness groups and negative relations with endemic species. Elevation was found to have higher relative influence on plant richness and distribution in Aberdare ranges forest. For effective conservation and management of biodiversity in Aberdare, localized dynamic conservation interventions are recommended in contrast to broad and static strategies. Establishment of conservation zones and migration corridors are necessary to safeguard biodiversity in line with envisaged global climatic vicissitudes.

The elevation gradient of lichen species richness in Nepal

2009 ◽  
Vol 42 (1) ◽  
pp. 83-96 ◽  
Author(s):  
Chitra Bahadur BANIYA ◽  
Torstein SOLHØY ◽  
Yngvar GAUSLAA ◽  
Michael W. PALMER
Keyword(s):  
Species Richness ◽  
Endemic Species ◽  
Elevation Gradient ◽  
Distribution Patterns ◽  
Lichen Species ◽  
Ecological Niches ◽  
Published Data ◽  
Elevation Gradients ◽  
Wide Range ◽  
Taxonomic Groups

AbstractThis study of elevation gradients of lichen species richness in Nepal aimed to compare distribution patterns of different life-forms, substratum affinities, photobiont types, and Nepalese endemism. Distribution patterns of lichens were compared with elevational patterns shown by a wide range of taxonomic groups of plants along the Nepalese Himalayan elevational gradient between 200–7400m. We used published data on the elevation records of 525 Nepalese lichen species to interpolate presence between the maximum and minimum recorded elevations, thereby giving estimates of lichen species richness at each 100-m elevational band. The observed patterns were compared with previously published patterns for other taxonomic groups. The total number of lichens as well as the number of endemic species (55 spp.) showed humped relationships with elevation. Their highest richness was observed between 3100–3400 and 4000–4100m, respectively. Almost 33% of the total lichens and 53% of the endemic species occurred above the treeline (>4300m). Non-endemic richness had the same response as the total richness. All growth forms showed a unimodal relationship of richness with elevation, with crustose lichens having a peak at higher elevations (4100–4200m) than fruticose and foliose lichens. Algal and cyanobacterial lichen richness, as well as corticolous lichen richness, all exhibited unimodal patterns, whereas saxicolous and terricolous lichen richness exhibited slightly bimodal relationships with elevation. The highest lichen richness at mid altitudes concurred with the highest diversity of ecological niches in terms of spatial heterogeneity in rainfall, temperature, cloud formation, as well as high phorophyte abundance and diversity implying large variation in bark roughness, moisture retention capacity, and pH. The slightly bimodal distributions of saxicolous and terricolous lichens were depressed at the elevational maximum of corticolous lichens.

scholarly journals The variation of bird diversity in various oil palm land cover in North Mamuju, West Sulawesi, Indonesia

2021 ◽  
Vol 22 (7) ◽  
Author(s):  
Sitti Ramlah ◽  
YANTO SANTOSA ◽  
NYOTO SANTOSO ◽  
SITI BADRIYAH RUSHAYATI
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Land Cover ◽  
Oil Palm ◽  
Bird Species ◽  
The Other ◽  
Bird Diversity ◽  
Number Of Species ◽  
High Species Diversity ◽  
Bird Species Diversity

Abstract. Ramlah S, Santosa Y, Santoso N, Rushayati SB. 2021. The variation of bird diversity in various oil palm land cover in North Mamuju, West Sulawesi, Indonesia. Biodiversitas 22: 3068-3074. The development of oil palm plantations provides various positive impacts. On the other hand, this development is suspected to bring negative impacts on biodiversity, especially reducing bird species diversity. Based on the other research, well-managed oil palm plantations that maintain high conservation value areas have high species diversity. This study aimed to identify bird species diversity in different types of oil palm plantation land covers in North Mamuju. Data observation of bird species was performed using the transect method. There were 4 transects on each land cover. The results of this study showed that the young oil palm area had a high index of diversity and species richness. The high species diversity in the young palm area was caused by habitat variations. There was a water flow that provides more feed sources. The distance between the young oil palm area and secondary forest area affected the number of species, species richness and diversity of bird species. The category of insectivore guild which included aerial insectivores and insectivores was the dominant guild in all types of land cover, both in the number of species and the number of individual abundances.

Fire, plant species richness and plants of significance to Australian desert Aboriginal people

2020 ◽  
Vol 29 (10) ◽  
pp. 939
Author(s):  
Neil Burrows ◽  
Paul Rampant ◽  
Graham Loewenthal ◽  
Allan Wills
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Aboriginal People ◽  
Unit Area ◽  
Plant Species Richness ◽  
Sandy Desert ◽  
Plant Resources ◽  
Total Plant ◽  
Harvesting Efficiency ◽  
Patch Burning

A survey was undertaken in the Great Sandy Desert, Western Australia, to document changes in total plant species richness and the richness of plants of significance to Aboriginal people, with time since fire. Species richness was highest in the early post-fire seral stages, then declined with time as ‘fire ephemerals’ completed their life cycle. Culturally significant plants, which comprised ~42% of all plants recorded, were found in all seral stages but were most abundant in the early stages post fire. A fine-scale mosaic of seral stages created by frequent patch burning provides a higher variety of plant resources per unit area, increasing harvesting efficiency of culturally important plants.

scholarly journals Why species richness of plants and herbivorous insects do or do not correlate

2020 ◽  
Author(s):  
Naoto Shinohara ◽  
Takehito Yoshida
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Insect Species ◽  
Herbivorous Insect ◽  
Insect Communities ◽  
Total Plant ◽  
Insect Species Richness ◽  
Opposing Effects ◽  
Generalist Insect ◽  
Number Of Plant Species

AbstractUnraveling the determinants of herbivorous insect diversity has been a major challenge in ecology. Despite the strong association between insect and plant species, previous studies conducted in natural systems have shown great variation in the strength of the correlation between their species richness. Such variation can be attributed to the proportion of generalist insect species (generality), though both higher and lower generality may weaken the correlation because 1) generalist insect species are less dependent on the number of plant species and 2) specialist insect species utilize only a part of the total plant species. To explore these opposing effects, we studied plant and herbivorous insect communities in semi-natural grasslands in Japan. Plant–insect interactions were evaluated in a unique way with a particular focus on the staying and herbivory behaviors of insects, which reflect their habitat use as well as host use. We fousnd that generality of insect communities negatively affected the correlation between species richness of plants and insects. However, such negative effect was significant only when the insect species richness was related with the number of plant species interacted with some insect species, instead of with that of total plant species. The results suggest that considering either of the opposing effects of insect generality is insufficient and they should be inclusively interpreted to understand the relationship between plant and insect species richness.

scholarly journals VII. The endemic flora of Ceylon, with reference to geographical distribution and evolution in general

1915 ◽  
Vol 206 (325-334) ◽  
pp. 307-342 ◽  
Keyword(s):  
Natural Selection ◽  
Endemic Species ◽  
Oceanic Islands ◽  
Flowering Plants ◽  
The Other ◽  
Local Conditions ◽  
Endemic Genera ◽  
Doubtful Species ◽  
Endemic Flora ◽  
Joseph Hooker

The completion of my revised catalogue of the Ceylon flora has enabled me to put together statistical notes on some of its more interesting features, and in the present paper I shall deal with the endemic flora. Though only separated from India by a narrow strait, which at Adam’s Bridge is barely 28 miles across, sprinkled with islets and sandbanks, and from 6 to 12 feet in depth at low water, Ceylon contains an immense endemic flora, which enables it to rank with many oceanic islands: even the Sandwich Islands have not so many. The flora of Ceylon consists of 2809 species of flowering plants,! and of these no fewer than 809 are endemic, or a proportion of 28.8 per cent. And these are not mere varieties, or doubtful species, but good Linnean species, accepted by such authorities as Trimen and Sir Joseph Hooker. On the other hand, the number of endemic genera is only 23 out of 1027, so that the island does not rise to the rank of a widely separated province in geographical botany. Incidentally, the facts about to be brought forward are an apparently insuperable objection to the theory of natural selection and adaptation. In previous papers dealing with the endemic flora of Ceylon I have endeavoured to prove that the endemic species have not been evolved in any kind of advantageous response to local conditions, and 1 have called attention to the fact that they are much rarer than the species of wider distribution that occur alongside of them.

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 Global shortfalls in extinction risk assessments for endemic flora

2020 ◽  
Author(s):  
R. V. Gallagher ◽  
S. Allen ◽  
M. C. Rivers ◽  
A. P. Allen ◽  
N. Butt ◽  
...  
Keyword(s):  
Plant Species ◽  
Endemic Species ◽  
Extinction Risk ◽  
Plant Conservation ◽  
Well Being ◽  
Global Strategy ◽  
Risk Assessments ◽  
Face Threats ◽  
Extinction Risk Assessment ◽  
Endemic Flora

SUMMARYThe Global Strategy for Plant Conservation (GSPC) ambitiously calls for an assessment of extinction risk for all recognised plant taxa by 20201. It is now clear that this target will not be met in the short-term; only 21-26% of known plant species have been assessed2 – a monumental shortfall in anticipated knowledge. Yet the need for risk assessments has never been more urgent. Plants are rapidly going extinct3,4 and face threats such as climate change5 and permanent deforestation6. Extinction risk assessments continue to provide the critical foundation to inform protection, management and recovery of plant species7,8, the loss of which will have clear consequences for maintaining planetary systems and human well-being9. Here, we rank countries of the world based on progress towards assessing the extinction risk to their endemic flora. Overall, 67% of country-based endemic species do not have an extinction risk assessment completed (143,294 species). We show that some of the world’s wealthiest nations, which also have relatively strong species protections, are failing to protect their unique flora by not systematically assessing risks to their endemic species.

scholarly journals Vascular plant species diversity of Mt. Etna (Sicily): endemicity, insularity and spatial patterns along the altitudinal gradient of the highest active volcano in Europe

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9875
Author(s):  
Saverio Sciandrello ◽  
Pietro Minissale ◽  
Gianpietro Giusso del Galdo
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Endemic Species ◽  
Altitudinal Gradient ◽  
Hot Spot ◽  
Vascular Plant ◽  
Plant Conservation ◽  
Active Volcano ◽  
Plant Species Richness ◽  
Mt Etna

Background Altitudinal variation in vascular plant richness and endemism is crucial for the conservation of biodiversity. Territories featured by a high species richness may have a low number of endemic species, but not necessarily in a coherent pattern. The main aim of our research is to perform an in-depth survey on the distribution patterns of vascular plant species richness and endemism along the elevation gradient of Mt. Etna, the highest active volcano in Europe. Methods We used all the available data (literature, herbarium and seed collections), plus hundreds of original (G Giusso, P Minissale, S Sciandrello, pers. obs., 2010–2020) on the occurrence of the Etna plant species. Mt. Etna (highest peak at 3,328 mt a.s.l.) was divided into 33 belts 100 m wide and the species richness of each altitudinal range was calculated as the total number of species per interval. In order to identify areas with high plant conservation priority, 29 narrow endemic species (EE) were investigated through hot spot analysis using the “Optimized Hot Spot Analysis” tool available in the ESRI ArcGIS software package. Results Overall against a floristic richness of about 1,055 taxa, 92 taxa are endemic, of which 29 taxa are exclusive (EE) of Mt. Etna, 27 endemic of Sicily (ES) and 35 taxa endemic of Italy (EI). Plant species richness slowly grows up to 1,000 m, then decreases with increasing altitude, while endemic richness shows an increasing percentage incidence along the altitudinal gradient (attributed to the increased isolation of higher elevation). The highest endemic richness is recorded from 2,000 up to 2,800 m a.s.l., while the highest narrow endemic richness (EE) ranges from 2,500 up to 2,800 m a.s.l. Life-form patterns clearly change along altitudinal gradient. In regard to the life-form of the endemics, the most represented are the hemicryptophytes, annual plants (therophytes) are prevailing at lower altitudes and show a decreasing trend with increasing elevation, while chamaephytes are featured by an increasing trend up to 3,100 m of altitude. Furthermore, the results of the hotspot analysis emphasize the high plant conservation priority areas localized in oro-mediterranean (1,800–2,400 m s.l.m.) and cryo-mediterranean (2,400–2,800 m) bioclimatic belts, in correspondence of the oldest substrates of the volcano. Conclusions High plant speciation rate caused by increasing isolation with elevation is the most plausible explanation for the largest active volcano in Europe. The high degree of endemic species on Mt. Etna is linked to its geographical, geological and climatic isolation, all important drivers of speciation acting on the population gene flows. The hot spot map obtained represents a useful support for help environmental decision makers to identify priority areas for plant conservation.

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