scholarly journals Disentangling Species Delineation and Guiding Conservation of Endangered Magnolias in Veracruz, Mexico

Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 673
Author(s):  
Fabián Augusto Aldaba Aldaba Núñez ◽  
Emily Veltjen ◽  
Esteban Manuel Martínez Martínez Salas ◽  
Marie-Stéphanie Samain
Keyword(s):  
Conservation Status ◽  
Full Range ◽  
Genetic Evidence ◽  
Primary Forest ◽  
Volcanic Area ◽  
Conservation Units ◽  
Separate Species ◽  
Representative Sampling ◽  
Conservation Projects ◽  
Very High

The Mexican state of Veracruz has suffered very high deforestation rates in the last few decades, and despite the establishment of protected areas and conservation projects, primary forest is now mainly persisting in mostly small, scattered, fragmented remnants. New species of Magnolia section Talauma in this state have been described with little to no reference to the already existing ones, potentially resulting in over-splitting, obscuring their taxonomic delineation and conservation status, and consequently conservation programs. To study the conservation units and their genetic diversity, we here employ 15 microsatellite markers on a highly representative sampling of 254 individuals of what are presumed to be five Magnolia species. The results support at least three species and maximum five main conservation units. We propose downgrading the latter to four, given morphological, ecological, demographical, and geographical considerations. Two out of the three sympatrically occurring species in the rainforest in the Los Tuxtlas volcanic area have weak genetic evidence to be considered separate species. Similarly, the individuals in the Sierra de Zongolica in central Veracruz, who bear a very high morphological and genetic similarity to Magnolia mexicana, have weak genetic evidence to be recognised as a separate species. Nonetheless, the individuals could be identified as Magnolia decastroi based on morphology, and further research including the full range of this species is recommended.

A- and B-site doping effect on physicochemical properties of Sr2−xBaxMMoO6 (M = Mg, Mn, Fe) double perovskites — candidate anode materials for SOFCs

2016 ◽  
Vol 09 (04) ◽  
pp. 1641002 ◽  
Author(s):  
Kun Zheng ◽  
Konrad Świerczek
Keyword(s):  
Physicochemical Properties ◽  
Solid Oxide Fuel Cells ◽  
Anode Materials ◽  
Full Range ◽  
Solid Oxide ◽  
Double Perovskites ◽  
Reducing Conditions ◽  
Redox Stability ◽  
Very High

In this work, we evaluate the physicochemical properties of Sr[Formula: see text]BaxMMoO6 (M [Formula: see text] Mg, Mn, Fe) double perovskites as alternative anode materials for solid oxide fuel cells, for which the effect of substitution of strontium by barium in a full range of compositions is studied. The crystal structure, microstructure, characterization of transport properties (electrical conductivity, Seebeck coefficient) and oxygen content as a function of temperature, as well as chemical stability in oxidizing and reducing conditions are discussed. Fe- and Mo-containing Sr[Formula: see text]BaxFeMoO6 oxides show very high total conductivities with values of 100–1000 S[Formula: see text][Formula: see text]cm[Formula: see text], while Sr[Formula: see text]BaxMgMoO6 present good redox stability.

scholarly journals Optical method for measuring bed topography and flow depth in an experimental flume

Solid Earth ◽  
2011 ◽  
Vol 2 (2) ◽  
pp. 143-154 ◽  
Author(s):  
A. Limare ◽  
M. Tal ◽  
M. D. Reitz ◽  
E. Lajeunesse ◽  
F. Métivier
Keyword(s):  
Optical Method ◽  
Full Range ◽  
Reference Plane ◽  
Flow Depth ◽  
Bed Topography ◽  
Braided Channel ◽  
Continuous Surface ◽  
Commercial Software Package ◽  
Moire Method ◽  
Very High

Abstract. We describe an optical method known as moiré for acquiring quasi-simultaneous measurements of bed topography and flow depth in laboratory experiments. The moiré method is based on projecting a fringe pattern (grating) on the bed and analyzing the deformation of the pattern caused by the topography with respect to a reference plane. The height of the object is encoded in the phase of the pattern and can be retrieved either through Fourier transform or phase shifting algorithms. The methodology enables image-based non-contact measurements over a continuous surface at very high spatial and temporal resolutions. We use a commercial software package of a moiré method called Light3D to map bed topography and flow depth in an experimental braided channel and demonstrate how the method can be used to characterize a full range of statistics not previously possible.

On the Sigmoidal Law Relating Association Value (A) and Scaled Meaningfulness (M′)

1968 ◽  
Vol 26 (2) ◽  
pp. 375-386 ◽  
Author(s):  
Clyde E. Noble ◽  
Patricia B. Sutker ◽  
Helen R. Jones
Keyword(s):  
Representative Sample ◽  
Full Range ◽  
Relative Number ◽  
Inductive Hypothesis ◽  
Cross Cultural ◽  
Average Error ◽  
Sigmoidal Function ◽  
Empirical Law ◽  
Range Of Values ◽  
Very High

This study was conducted to test an inductive hypothesis, based on judgments of the relative number of associations ( a′) evoked by 2100 CVC trigrams in 200 Montana college Ss, that association value ( a) is a sigmoidal function of scaled meaningfulness ( m′). Whereas the earlier investigation used a representative sample of only 21 CVCs to compute m′, we selected 500 stimuli from the full range of values and had them rated by 200 Georgia college Ss. Measures of reliability for the a′ scale ( r = .993) and of internal consistency for the m′ scale (average error = 2.8%) are again very high. The cross-cultural regressions for the a and m′ scales are both linear, with r ≥ .97 for mean scores grouped in 25 categories of 20 CVCs each. Confirming and extending Noble's 1957 and 1961 findings, the present function relating a and m′ is clearly S-shaped and may be regarded as an empirical law. The analysis-of-variance ( η2) test of curvilinearity, applied to 12 equidistant groupings using all 500 CVCs, is significant ( P < .001). Among the major implications are: (1) the contemporary m′ scale is superior to the classical a scale and its cognates, (2) the practice of treating these two variables as identical or even linearly related is erroneous, (3) continued equivocation about a and m′ in research on verbal behavior can lead to serious errors of prediction and faulty explanatory inferences.

scholarly journals Distribution, habitat selection and behaviour of the East Coast Akalat Sheppardia gunningi sokokensis in Kenya and Tanzania

2000 ◽  
Vol 10 (2) ◽  
pp. 115-130 ◽  
Author(s):  
Erwin Nemeth ◽  
Leon Bennun
Keyword(s):  
Habitat Selection ◽  
Dead Wood ◽  
East Coast ◽  
Conservation Status ◽  
Primary Forest ◽  
Coastal Forests ◽  
East African ◽  
Elephant Population ◽  
Shimba Hills ◽  
Selection Of

This study investigated the distribution and habitat selection of the globally threatened East Coast Akalat Sheppardia gunningi sokokensis in Arabuko-Sokoke Forest, the Shimba Hills (both Kenya) and the lowland East Usambara Mountains (Tanzania). The species is more abundant than originally thought. In Arabuko-Sokoke Forest, akalats occur in two of the main vegetation types, and an estimated 7,500–9,000 territories represent one of the largest populations of this species in the world. Akalats occurred at similar densities to those in Arabuko-Sokoke (c. 0.5 pairs/ha) in parts of Shimba Hills and East Usambaras, but were more patchily distributed. This akalat prefers areas where the undergrowth is partially open with large amounts of dead wood. It forages on or near the ground. In Arabuko-Sokoke Forest, areas where akalats were present had a higher abundance of ground-dwelling arthropods than areas where they were not. The akalat inhabits both primary forest and regenerated areas that have been selectively logged probably more than 20 years ago. Despite its relatively high densities where it occurs, this species (like other threatened birds in the East African coastal forests) is very patchily distributed and dependent on a habitat that is now highly fragmented and under considerable human pressure. The conservation situation in Arabuko-Sokoke gives cause for concern, and the destructive effects of a large elephant population threaten the forests of the Shimba Hills. The conservation status of the lowland Usambara Mountains is probably better and more stable.

scholarly journals Influences of oceanic islands and the Pleistocene on the biogeography and evolution of two groups of Australasian parrots (Aves: Psittaciformes: Eclectus roratus, Trichoglossus haematodus complex). Rapid evolution and implications for taxonomy and conservation

2016 ◽  
Vol 3 (2) ◽  
pp. 47-66
Author(s):  
Michael P. Braun ◽  
Matthias Reinschmidt ◽  
Thomas Datzmann ◽  
David Waugh ◽  
Rafael Zamora ◽  
...  
Keyword(s):  
Species Complex ◽  
Rapid Evolution ◽  
New Guinea ◽  
Distinct Species ◽  
Genetic Evidence ◽  
Valid Species ◽  
Separate Species ◽  
Species Complexes ◽  
Mitochondrial Cytochrome B ◽  
Avian Diversification

AbstractThe Australasian region is a centre of biodiversity and endemism, mainly based on the tropical climate in combination with the large amount of islands. During the Pleistocene, islands of the Sahul Shelf (Australia, New Guinea, Aru Islands) had been part of the same land mass, while islands within the Wallacea (Lesser Sunda Islands, Moluccas, Sulawesi etc.) remained isolated. We investigated biogeographical avian diversification patterns of two species complexes across the Wallacea and the Sahul Shelf: the Eclectus Parrot Eclectus roratus Wagler, 1832, and the Rainbow Lorikeet Trichoglossus haematodus Linnaeus, 1771. Both species are represented by a large number of described geographical subspecies. We used mitochondrial cytochrome b (cyt b) sequences for phylogenetic and network analysis to detect biogeographic roles of islands and avian diversification patterns. The number of threatened taxa in this region is increasing rapidly and there is an urgent need for (sub-)species conservation in this region. Our study provides first genetic evidence for treating several island taxa as distinct species. In both species complexes similar genetic patterns were detected. Genetic diversification was higher across the islands of the Wallacea than across the islands of the Sahul Shelf. Divergence in E. roratus can be dated back about 1.38 million years ago, whereas in the younger T. haematodus it was 0.80 million years ago. Long distance dispersal was the most likely event for distribution patterns across the Wallacea and Sahul Shelf. The geographic origin of the species-complex Eclectus roratus spp. is supposed to be Wallacean, but for the species-complex Trichoglossus haematodus spp. it is supposed to be non-Wallacean. Trichoglossus euteles, so far considered a distinct species, clearly belongs to the Trichoglossus-haematodus-complex. The only case of sympatry in the complex is the distribution of T. (h.) euteles and T. h. capistratus on Timor, which means a rapid evolution from one ancestor into two distinct species within only 800,000 years. For all other taxa a Checkerboard distribution pattern is present. In this complex, 8 taxa are already treated as separate species (del Hoyo et al. 2014). Based on genetic evidence, the following populations are supported to represent phylogenetic units: (1) N New Guinea (haematodus) incl. Biak (rosenbergii), Bismarck Archipelago (massena), and New Caledonia (deplanchii); (2) Flores (weberi); (3) E Australia (moluccanus) incl. Aru Islands (nigrogularis) and S New Guinea (caeruleiceps); (4) N Australia (rubritorquis); (5) Timor 1st lineage (capistratus) incl. Sumba (fortis); (6) Bali and Lombok (mitchellii); (7) Sumbawa (forsteni); (8) Timor 2nd lineage (euteles). Those 8 phylogenetic units are not identical to the 8 species listed by del Hoyo et al. (2014). Several populations on smaller islands are under decline, a separate species status may lead to a higher conservation status in both species complexes, which are currently listed as “Least Concern”. Eclectus roratus is currently treated as monospecific. Based on genetic evidence, the following populations are suggested being treated as valid species: (1) Sumba (Eclectus cornelia), (2) Tanimbar Islands (E. riedeli), (3) Moluccas (E. roratus), and (4) New Guinea (E. polychloros incl. Aru Islands (E. aruensis), and Solomon Island (E. solomonensis).

Delineation of conservation units in an endangered marsupial, the southern brown bandicoot (Isoodon obesulus obesulus), in South Australia/western Victoria, Australia

2014 ◽  
Vol 62 (5) ◽  
pp. 345 ◽  
Author(s):  
You Li ◽  
Melanie L. Lancaster ◽  
Susan M. Carthew ◽  
Jasmin G. Packer ◽  
Steven J. B. Cooper
Keyword(s):  
Conservation Management ◽  
Conservation Status ◽  
South Australia ◽  
Disjunct Distribution ◽  
Conservation Units ◽  
Evolutionarily Significant Units ◽  
Population Analyses ◽  
High Conservation ◽  
Western Victoria ◽  
Evolutionary Lineages

Conservation programs for threatened species are greatly benefiting from genetic data, for their power in providing knowledge of dispersal/gene flow across fragmented landscapes and for identifying populations of high conservation value. The endangered southern brown bandicoot (Isoodon obesulus obesulus) has a disjunct distribution range in South Australia, raising the possibility that populations of the subspecies may represent distinct conservation units. In the current study, we used a combination of 14 microsatellite and two mitochondrial sequence markers to investigate the phylogeography and population structure of I. o. obesulus in South Australia and south-western Victoria, with the aim of identifying any potential evolutionarily significant units and management units relevant to conservation management. Our phylogenetic/population analyses supported the presence of two distinct evolutionary lineages of I. o. obesulus. The first lineage comprised individuals from the Mount Lofty Ranges, Fleurieu Peninsula and Kangaroo Island. A second lineage comprised individuals from the south-east of South Australia and south-western Victoria. We propose that these two lineages represent distinct evolutionarily significant units and should be managed separately for conservation purposes. The findings also raise significant issues for the national conservation status of I. o. obesulus and suggest that the current subspecies classification needs further investigation.

Increasing our knowledge of Brazilian bamboos: two new species of Chusquea subg. Rettbergia (Bambusoideae, Poaceae)

Phytotaxa ◽  
2014 ◽  
Vol 161 (3) ◽  
pp. 201 ◽  
Author(s):  
Aline Costa Mota ◽  
REYJANE PATRÍCIA DE OLIVEIRA ◽  
LYNN G. CLARK
Keyword(s):  
New Species ◽  
Atlantic Forest ◽  
Conservation Status ◽  
Minas Gerais ◽  
Foliage Leaf ◽  
Ecological Aspects ◽  
Two New Species ◽  
Woody Bamboos ◽  
Very High ◽  
High Diversity

Brazil includes a very high diversity of bamboos, but this diversity is far from completely known. We increase the list of Brazilian woody bamboos by describing two new species of Chusquea, which belong to subgenus Rettbergia. Chusquea ciliatifolia sp. nov. differs from other species of this subgenus by its mottled culms, distinctly ciliate margins of the foliage leaf blades and pilose synflorescences; and C. mirabilis sp. nov. by the presence of branches with sericeous girdles. Both C. ciliatifolia and C. mirabilis occur exclusively in the Atlantic Forest, from the states of Bahia and Minas Gerais, known only from five and three populations, respectively. Comments on morphology, taxonomic relationships, ecological aspects, and conservation status of these new species are provided.

scholarly journals The biology and conservation status of Central and South American Falconiformes: a survey of current knowledge

1995 ◽  
Vol 5 (2-3) ◽  
pp. 325-340 ◽  
Author(s):  
Richard O. Bierregaard
Keyword(s):  
South America ◽  
Current Knowledge ◽  
Conservation Status ◽  
Primary Forest ◽  
Extensive Literature ◽  
South American ◽  
Current State ◽  
North Eastern ◽  
Extreme North ◽  
América Del Sur

SummaryBased on an extensive literature review for the 81 species of Falconiformes (excluding vultures) that breed primarily in Central and South America, I summarize the current state of our knowledge of the biology and conservation status of these birds. Most of what is known about the diurnal raptors in the region is based on studies carried out in the southern U.S.A., the Petén of Guatemala, extreme north-eastern South America (Venezuela through the Guianas) and Chile. The least-known species are residents of primary forest, especially in the generaAccipiter, LeucoptemisandMicrastur. Nests remain undescribed for 19 species, and less than five nests have been described for an additional 12 species. No prey data are available for six species and only anecdotal data have been published for a further 25 species. Breeding behaviour is unknown for 27 species and known only anecdotally for an additional 18. The migratory habits of 28 species are poorly understood. Available data permit a reasonable assessment of the conservation status for 39 species and a well-educated guess for another 31, but any assessment for the remaining 11 would be speculation at best.Basado en un estudio muy extensivo de la literatura para 81 especies de Falconiformes(excluyendo Cathartidae) que se aparean principalmente en Centro y Sur América, hago un resumen de nuestro conocimiento más actual de la biologia y el estado de conservación en que se encuentran estas aves. La mayor parte de la información que se tiene sobre raptores diurnos de la región está basada en estudios que fueron llevados acabo en el sur de los Estados Unidos, el Petén en Guatemala, la parte noreste de América del Sur (Venezuela hasta las Guianas) y Chile. Las especies menos conocidos son residentes de bosque primario, especialmente de los génerosAccipiter, Leucoptemis y Micrastur. Falta describir nidos para 19 especies y menos de cinco nidos han sido descritos para 12 especies adicionales. No hay informacion sobre la alimentatión para seis especies y solamente información anecdotal ha sido publicada para 25 especies adicionales. Comportamiento de apareo se desconoce para 27 especies y solamente es conocido por anécdotas par 18 especies adicionales, Las costumbres migratorias de 28 especies se conocen muy poco. Información disponible permite juzgar razonablemente el estado de conservación para 39 especies y se puede estimarlo para 31 más, pero el juzgar de los 11 que restan seria solamente especulación.

scholarly journals The remnants of restinga habitats in the brazilian Atlantic Forest of Rio de Janeiro state, Brazil: habitat loss and risk of disappearance

2007 ◽  
Vol 67 (2) ◽  
pp. 263-273 ◽  
Author(s):  
CFD. Rocha ◽  
HG. Bergallo ◽  
M. Van Sluys ◽  
MAS. Alves ◽  
CE. Jamel
Keyword(s):  
Habitat Loss ◽  
Rio De Janeiro ◽  
Conservation Status ◽  
Legal Protection ◽  
Field Work ◽  
The State ◽  
Conservation Units ◽  
Landsat 7 ◽  
Extensive Degradation ◽  
Janeiro State

"Restingas" (herbaceous/shrubby coastal sand-dune habitats) used to cover most of Rio de Janeiro State coast, and have suffered extensive degradation over the last five centuries. Using satellite images and field work, we identified the remaining restingas in the State, recording the factors that might cause their degradation. We used two mosaics of Landsat 7 scenes (spatial resolution 15 and 30 m) to map and evaluate preliminarly the remaining areas and conservation status. Each remnant area was checked in the field, degraded areas within it were mapped and subtracted from the remnants. We identified 21 restinga remnants totalling 105,285 ha. The largest and smallest restinga remnants were Jurubatiba (25,141 ha) and Itaipu (23 ha), respectively. We identified 14 causes of degradation. The most important were vegetation removal for housing developments, establishment of exotic plant species, change of original substrate, and selective removal of species of economic importance for the horticultural industry. All restingas had disturbed parts under strong pressure due to human activities. Due to intense habitat loss, and occurrence of endemic/threatened vertebrate species in restinga habitats, we strongly indicate the implementation of new conservation units to protect these fragile remnants. This habitat is steadily decreasing and most remnants lack legal protection. Therefore, under the current human pressure most of this unique habitat is likely to be lost from the State within the next few years.

scholarly journals Biogeography and conservation of Andean and Trans-Andean populations of Pyrrhura parakeets in Colombia: Modelling geographic distributions to identify independent conservation units

2012 ◽  
Vol 22 (4) ◽  
pp. 445-461 ◽  
Author(s):  
ESTEBAN BOTERO-DELGADILLO ◽  
CARLOS ANDRÉS PÁEZ ◽  
NICHOLAS BAYLY
Keyword(s):  
Conservation Status ◽  
Iucn Red List ◽  
Conservation Priorities ◽  
Nominal Species ◽  
Conservation Units ◽  
Humid Forest ◽  
Geographic Ranges ◽  
Biogeographic Patterns ◽  
Area Of Occupancy ◽  
Biogeographic History

SummaryThe criteria and categories of the IUCN red list can be applied to any taxonomic unit, including taxa below species level or non-formally described forms, but this is seldom practiced. Because conservation priorities largely focus on well-established taxa that deserve urgent action, cryptic species may be facing a critical situation. This could be the case for some Andean and trans-Andean populations of Pyrrhura parakeets in Colombia that have restricted and isolated geographic ranges, and whose conservation status has been overlooked because nominal species covering them are considered of “Least Concern”. As part of research into the biogeographic history and biogeographic patterns of the genus Pyrrhura, we used MaxEnt modelling to make a first approach to the geographic distribution and conservation status of these populations, and to determine if they could be considered independent conservation units. As with other members of Pyrrhura, we found that their climatic niche was restricted to humid regions of the Andes and the Andean foothills, resulting in isolated and discontinuous distributions associated with the Tropical humid forest Zonobiome. Comparing our estimates of area of occupancy with the established thresholds for IUCN criterion B2, the four subspecies studied could be considered threatened. The small geographic ranges, apparent vulnerability to forest fragmentation compared with other parrots, and extensive habitat loss experienced by the Andean and trans-Andean subspecies of P. melanura and P. picta allow us to conclude that they are valid conservation units. Although further research on these taxa is necessary, our results imply that they must be included as target populations in local and national policies for management plans and decision making, and urgent actions are needed for the subspecies of P. picta such as P. p. subandina and P. p. caeruleiceps.

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