scholarly journals Islands in the desert: environmental distribution modelling of endemic flora reveals the extent of Pleistocene tropical relict vegetation in southern Arabia

2019 ◽  
Vol 124 (3) ◽  
pp. 411-422 ◽  
Author(s):  
James S Borrell ◽  
Ghudaina Al Issaey ◽  
Darach A Lupton ◽  
Thomas Starnes ◽  
Abdulrahman Al Hinai ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Narrow Range ◽  
Biodiversity Hotspot ◽  
Environmental Data ◽  
Distribution Data ◽  
Endemic Plants ◽  
Environmental Niche ◽  
Environmental Distribution ◽  
Southern Arabia ◽  
Endemic Flora

AbstractBackground and AimsSouthern Arabia is a global biodiversity hotspot with a high proportion of endemic desert-adapted plants. Here we examine evidence for a Pleistocene climate refugium in the southern Central Desert of Oman, and its role in driving biogeographical patterns of endemism.MethodsDistribution data for seven narrow-range endemic plants were collected systematically across 195 quadrats, together with incidental and historic records. Important environmental variables relevant to arid coastal areas, including night-time fog and cloud cover, were developed for the study area. Environmental niche models using presence/absence data were built and tuned for each species, and spatial overlap was examined.Key ResultsA region of the Jiddat Al Arkad reported independent high model suitability for all species. Examination of environmental data across southern Oman indicates that the Jiddat Al Arkad displays a regionally unique climate with higher intra-annual stability, due in part to the influence of the southern monsoon. Despite this, the relative importance of environmental variables was highly differentiated among species, suggesting that characteristic variables such as coastal fog are not major cross-species predictors at this scale.ConclusionsThe co-occurrence of a high number of endemic study species within a narrow monsoon-influenced region is indicative of a refugium with low climate change velocity. Combined with climate analysis, our findings provide strong evidence for a southern Arabian Pleistocene refugium in Oman’s Central Desert. We suggest that this refugium has acted as an isolated temperate and mesic island in the desert, resulting in the evolution of these narrow-range endemic flora. Based on the composition of species, this system may represent the northernmost remnant of a continuous belt of mesic vegetation formerly ranging from Africa to Asia, with close links to the flora of East Africa. This has significant implications for future conservation of endemic plants in an arid biodiversity hotspot.

scholarly journals Islands in the desert: Environmental distribution modelling of endemic flora reveals the extent of Pleistocene tropical relict vegetation in southern Arabia

2019 ◽  
Author(s):  
James S. Borrell ◽  
Ghudaina Al Issaey ◽  
Darach A. Lupton ◽  
Thomas Starnes ◽  
Abdulrahman Al Hinai ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Narrow Range ◽  
Biodiversity Hotspot ◽  
Environmental Data ◽  
Distribution Data ◽  
Endemic Plants ◽  
Environmental Niche ◽  
Environmental Distribution ◽  
Southern Arabia ◽  
Endemic Flora

ABSTRACTBackground and AimsSouthern Arabia is a global biodiversity hotspot with a high proportion of endemic desert-adapted plants. Here we examine evidence for a Pleistocene climate refugium in the southern Central Desert of Oman, and its role in driving biogeographical patterns of endemism.MethodsDistribution data for seven narrow-range endemic plants were collected systematically across 195 quadrats, together with incidental and historic records. Important environmental variables relevant to arid coastal areas, including night time fog and cloud cover were developed for the study area. Environmental niche models were built and tuned for each species and spatial overlap examined.Key ResultsA region of the Jiddat Al Arkad reported independent high model suitability for all species. Examination of environmental data across southern Oman indicates that the Jiddat Al Arkad displays a regionally unique climate with higher intra-annual stability, due in part to the influence of the southern monsoon. Despite this, relative importance of environmental variables was highly differentiated among species, suggesting characteristic variables such as coastal fog are not major cross-species predictors at this scale.ConclusionsThe co-occurrence of a high number of endemic study species within a narrow monsoon-influenced region is indicative of a refugium with low climate change velocity. Combined with climate analysis, our findings provide strong evidence for a southern Arabian Pleistocene refugium in the Oman’s Central Desert. We suggest this refugium has acted as an isolated temperate and mesic island in the desert, resulting in the evolution of these narrow-range endemic flora. Based on the composition of species, this system may represent the northernmost remnant of a continuous belt of mesic vegetation formerly ranging from Africa to Asia, with close links to the flora of East Africa. This has significant implications for future conservation of endemic plants in an arid biodiversity hotspot.

scholarly journals Climate variability impacts on diversification processes in a biodiversity hotspot: a phylogeography of ancient pseudoscorpions in south-western Australia

2019 ◽  
Vol 186 (4) ◽  
pp. 934-949 ◽  
Author(s):  
Danilo Harms ◽  
J Dale Roberts ◽  
Mark S Harvey
Keyword(s):  
Phylogenetic Analyses ◽  
Distribution Patterns ◽  
Biodiversity Hotspot ◽  
Molecular Dating ◽  
Environmental Niche ◽  
Ecological Niche Models ◽  
The South ◽  
Niche Modelling ◽  
South West ◽  
Western Division

Abstract The south-western division of Australia is the only biodiversity hotspot in Australia and is well-known for extreme levels of local endemism. Climate change has been identified as a key threat for flora and fauna, but very few data are presently available to evaluate its impact on invertebrate fauna. Here, we derive a molecular phylogeography for pseudoscorpions of the genus Pseudotyrannochthonius that in the south-west are restricted to regions with the highest rainfall. A dated molecular phylogeny derived from six gene fragments is used for biogeographic reconstruction analyses, spatial mapping, environmental niche-modelling, and to infer putative species. Phylogenetic analyses uncover nine clades with mostly allopatric distributions and often small linear ranges between 0.5 and 130 km. Molecular dating suggests that the origins of contemporary diversity fall into a period of warm/humid Palaeogene climates, but splits in the phylogeny coincide with major environmental shifts, such as significant global cooling during the Middle Miocene. By testing several models of historical biogeography available for the south-west, we determine that Pseudotyrannochthonius is an ancient relict lineage that principally follows a model of allopatric speciation in mesic zone refugia, although there are derivations from this model in that some species are older and distribution patterns more complex than expected. Ecological niche models indicate that drier and warmer future climates will lead to range contraction towards refugia of highest rainfall, probably mimicking past variations that have generated high diversity in these areas. Their conservation management will be crucial for preserving the unique biodiversity heritage of the south-west.

Checklist of the endemic vascular plants of Paraguay

Phytotaxa ◽  
2018 ◽  
Vol 384 (1) ◽  
pp. 1
Author(s):  
MARÍA DEL CARMEN PEÑA CHOCARRO ◽  
JUANA DE EGEA
Keyword(s):  
Vascular Plants ◽  
Primary Data ◽  
Endemic Plants ◽  
Voucher Specimens ◽  
Herbarium Collections ◽  
Endemic Flora

We present a list of endemic plants of Paraguay, which includes 374 taxa from 52 families and 162 genera based on the revision of primary data (herbarium collections). Synonyms, habit, distribution in Paraguay and all the voucher specimens seen or cited in recent bibliographies or in the consulted databases are provided for each taxon. A brief analysis of the diversity and importance of this endemic flora is presented. A list of excluded species, which were considered as endemics in previous publications, is also included.

scholarly journals Fish Functional Traits Correlated with Environmental Variables in a Temperate Biodiversity Hotspot

PLoS ONE ◽  
2014 ◽  
Vol 9 (3) ◽  
pp. e93237 ◽  
Author(s):  
Benjamin P. Keck ◽  
Zachary H. Marion ◽  
Derek J. Martin ◽  
Jason C. Kaufman ◽  
Carol P. Harden ◽  
...  
Keyword(s):  
Functional Traits ◽  
Environmental Variables ◽  
Biodiversity Hotspot

scholarly journals Spatial-temporal analysis of the diet of a non-native fish in the Santa Cruz Reservoir, Brazilian semi-arid

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Jônnata Fernandes de Oliveira ◽  
Jean Carlos Dantas de Oliveira ◽  
José Luís Costa Novaes ◽  
Antonia Elissandra Freire de Souza ◽  
Marla Melise Oliveira de Sousa ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Abiotic Factors ◽  
Temporal Analysis ◽  
Arid Environment ◽  
Temporal Variations ◽  
Environmental Data ◽  
Animal Origin ◽  
Santa Cruz ◽  
Main Item ◽  
Semi Arid

Abstract Aim The diet of Plagioscion squamosissimus present in the Santa Cruz Reservoir, Rio Grande do Norte, Brazil, was investigated, evaluating the influences of spatial and temporal variations and abiotic factors in the utilization of food resources. Methods The samplings were performed quarterly between February 2011 and November 2014. Of the 525 specimens captured, 375 presented food items in the stomachs. The diet was determined using: (i) Feeding Index (IAi); (ii) and the graphical interpretation of the food strategy through non-metric multidimensional scaling (NMDS) analyzes, the differences in diet being tested from Permutational Multivariate Analyzes of Variance (PERMANOVA). To verify if environmental variables influence the Canonical Correspondence Analyzes (CCA) were used, using the data from the IAi the environmental data, being the significance of the axes tested through Monte Carlo simulations. Results The species feed mainly on items of animal origin, vegetable being a resource ingested accidentally. The diet was composed of shrimp, fish, insect, mollusk and vegetable, the latter rarely found. The shrimp was the main item (92.57%) and the insects (7.24%) accessory items. Spatial and temporal ordering demonstrated that the species didn’t present variation in diet composition, as well as a low association between diet and environmental variables. Conclusion P. squamosissimus is characterized as carcinophagous, due to the predominance of shrimp in its diet, evidencing that the species is adapted to the conditions offered by the Brazilian semi-arid environment.

scholarly journals Recruitment of oyster in artificial collectors on the Amazon macrotidal mangrove coast

2019 ◽  
Vol 49 (3) ◽  
Author(s):  
Izabel Cristina da Silva Almeida Funo ◽  
Ícaro Gomes Antonio ◽  
Yllana Ferreira Marinho ◽  
Josinete Sampaio Monteles ◽  
Rodolf Gabriel Prazeres Silva Lopes ◽  
...  
Keyword(s):  
Environmental Variables ◽  
Recruitment Rate ◽  
Environmental Data ◽  
Genetic Identification ◽  
Rainy Period ◽  
Pet Bottles ◽  
Tukey Test ◽  
Spat Collection ◽  
Crassostrea Rhizophorae ◽  
The Moment

ABSTRACT: The purpose of this study was to determine the moment of the year for the oyster recruitment and define the type of collector and environmental conditions that maximize recruitment. Collections were conducted, during 12 months, on Amazon Macrotidal Mangrove at two different sites: raft (point I) and mangrove (point II). In each location three types of collectors were used (1) transparent PET bottles, (2) green PET bottles, and (3) PVC sheets, each with three replicates. Spats were counted and measured at 45-day intervals, while the environmental data were measured every two weeks. Identification of oyster species occurred by genetic testing (multiplex PCR) by randomly selecting individuals by sampling. Results indicated spat capturing was significantly influenced by the collector type, location and period of collection (P<0.05, MANOVA) with significantly higher recruitment in the PVC collector (P<0.05, Tukey test). Oyster recruitment occurred throughout the year, suggesting that these individuals reproduce during all months; however, months with less rain and greater salinity were the best for spat collection, while the rainy period with lower salinity proved to be the best for individuals growth. The location in interaction with the environmental variables, mainly salinity, has a significant effect on the recruitment rate of spat and on their size, so that point II (mangrove) had the best results for recruitment and point I (raft) provided the spats of the largest size. Genetic identification verified two native oysters species (Crassostrea gasar and Crassostrea rhizophorae) in both points (I and II).

Examining Local Transferability of Predictive Species Distribution Models for Invasive Plants: An Example with Cogongrass (Imperata cylindrica)

2011 ◽  
Vol 4 (4) ◽  
pp. 390-401 ◽  
Author(s):  
Gary N. Ervin ◽  
D. Christopher Holly
Keyword(s):  
Invasive Species ◽  
Species Distribution ◽  
Species Distribution Models ◽  
Imperata Cylindrica ◽  
Environmental Data ◽  
Training Data ◽  
Distribution Data ◽  
Strongly Correlated ◽  
Distribution Models ◽  
Tree Canopy Cover

AbstractSpecies distribution modeling is a tool that is gaining widespread use in the projection of future distributions of invasive species and has important potential as a tool for monitoring invasive species spread. However, the transferability of models from one area to another has been inadequately investigated. This study aimed to determine the degree to which species distribution models (SDMs) for cogongrass, developed with distribution data from Mississippi (USA), could be applied to a similar area in neighboring Alabama. Cogongrass distribution data collected in Mississippi were used to train an SDM that was then tested for accuracy and transferability with cogongrass distribution data collected by a forest management company in Alabama. Analyses indicated the SDM had a relatively high predictive ability within the region of the training data but had poor transferability to the Alabama data. Analysis of the Alabama data, via independent SDM development, indicated that predicted cogongrass distribution in Alabama was more strongly correlated with soil variables than was the case in Mississippi, where the SDM was most strongly correlated with tree canopy cover. Results suggest that model transferability is influenced strongly by (1) data collection methods, (2) landscape context of the survey data, and (3) variations in qualitative aspects of environmental data used in model development.

The pholcid spiders of Sri Lanka (Araneae: Pholcidae)

Zootaxa ◽  
2019 ◽  
Vol 4550 (1) ◽  
pp. 1
Author(s):  
BERNHARD A. HUBER
Keyword(s):  
New Species ◽  
Sri Lanka ◽  
Western Ghats ◽  
Native Species ◽  
Biodiversity Hotspot ◽  
Distribution Data ◽  
Sri Lankan ◽  
Southwestern Part ◽  
Males And Females ◽  
The Western Ghats

As part of the Western Ghats-Sri Lanka biodiversity hotspot, Sri Lanka harbors a rich and diverse fauna, especially in the perhumid southwestern part of the island. However, many invertebrate groups such as spiders continue to be poorly studied. The present paper reviews our knowledge about Pholcidae, a family of spiders that is well represented in Sri Lanka, both by numerous (10) introduced species and by a rich native fauna in five genera (described native Sri Lankan species in parentheses): Belisana Thorell, 1898 (6), Leptopholcus Simon, 1893 (1), Pholcus Walckenaer, 1805 (4), Tissahamia Huber, 2018 (4), and Wanniyala Huber & Benjamin, 2005 (9). Fourteen species are newly described: Belisana minneriya sp. n., B. badulla sp. n., B. gowindahela sp. n.; Pholcus metta sp. n., P. puranappui sp. n., P. uva sp. n.; Tissahamia karuna sp. n.; Wanniyala mudita sp. n., W. orientalis sp. n., W. upekkha sp. n., W. ohiya sp. n., W. viharekele sp. n., W. mapalena sp. n., and W. labugama sp. n.. All new species are described from males and females. New Sri Lankan records are given for 16 previously described species. Distribution data suggest that most or all of the 24 native species might be endemic to Sri Lanka, but the Indian pholcid fauna remains almost entirely unknown. 

scholarly journals The scale of the whale: using video-tag data to evaluate sea-surface ice concentration from the perspective of individual Antarctic minke whales

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Jacob M. J. Linsky ◽  
Nicole Wilson ◽  
David E. Cade ◽  
Jeremy A. Goldbogen ◽  
David W. Johnston ◽  
...  
Keyword(s):  
Satellite Imagery ◽  
Antarctic Peninsula ◽  
Environmental Variables ◽  
Cloud Cover ◽  
Video Data ◽  
Environmental Data ◽  
Minke Whales ◽  
Ice Concentration ◽  
Surface Ice ◽  
The Antarctic

Abstract Background Advances in biologging technology allow researchers access to previously unobservable behavioral states and movement patterns of marine animals. To relate behaviors with environmental variables, features must be evaluated at scales relevant to the animal or behavior. Remotely sensed environmental data, collected via satellites, often suffers from the effects of cloud cover and lacks the spatial or temporal resolution to adequately link with individual animal behaviors or behavioral bouts. This study establishes a new method for remotely and continuously quantifying surface ice concentration (SIC) at a scale relevant to individual whales using on-animal tag video data. Results Motion-sensing and video-recording suction cup tags were deployed on 7 Antarctic minke whales (Balaenoptera bonaerensis) around the Antarctic Peninsula in February and March of 2018. To compare the scale of camera-tag observations with satellite imagery, the area of view was simulated using camera-tag parameters. For expected conditions, we found the visible area maximum to be ~ 100m2 which indicates that observations occur at an equivalent or finer scale than a single pixel of high-resolution visible spectrum satellite imagery. SIC was classified into one of six bins (0%, 1–20%, 21–40%, 41–60%, 61–80%, 81–100%) by two independent observers for the initial and final surfacing between dives. In the event of a disagreement, a third independent observer was introduced, and the median of the three observer’s values was used. Initial results (n = 6) show that Antarctic minke whales in the coastal bays of the Antarctic Peninsula spend 52% of their time in open water, and only 15% of their time in water with SIC greater than 20%. Over time, we find significant variation in observed SIC, indicating that Antarctic minke occupy an extremely dynamic environment. Sentinel-2 satellite-based approaches of sea ice assessment were not possible because of persistent cloud cover during the study period. Conclusion Tag-video offers a means to evaluate ice concentration at spatial and temporal scales relevant to the individual. Combined with information on underwater behavior, our ability to quantify SIC continuously at the scale of the animal will improve upon current remote sensing methods to understand the link between animal behavior and these dynamic environmental variables.

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