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1.
Plant Biol (Stuttg) ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38979801

RESUMEN

Polyploidy can cause differences in phenotypic and physiological traits among different cytotypes of the same species. Polyploids may have larger organs or occupy different ecological niches than their diploid counterparts, therefore they are hypothesized to have larger distributions or prosper in stressful environments, such as higher elevations. The Cypress spurge (Euphorbia cyparissias L.; Euphorbiaceae) is a widespread European heteroploid species including di- (2x), tetra- (4x) and hexaploid (6x) cytotypes. We tested the hypotheses that polyploids are more widespread and more abundant at higher elevations and have larger organs than their diploid ancestors in the case of E. cyparissias. We also analysed whether genome downsizing had occurred after polyploidisation. We conducted a comprehensive geographic sampling of 617 populations of E. cyparissias throughout Europe. We estimated their relative genome size using flow cytometry and inferred ploidy level of each population. We scored 13 morphological traits of vegetative and seed characters and performed statistical analyses. The study indicates that polyploidisation facilitated colonisation of new areas in E. cyparissias, where the tetraploids are most widespread, whereas the diploids are limited to putative Pleistocene refugia, mostly in southern Europe. On the other hand, the three ploidies do not differ in their elevational distribution. Although some quantitative morphological traits exhibited an increasing trend with increasing ploidy, most traits did not differ significantly among the three ploidies, and there was no overall phenotypic differentiation among them. Given that individuals of different ploidies thrive in similar habitats across the same elevations, we suggest that ecological segregation following polyploidisation is a more important trigger for morphological differentiation than polyploidisation itself in autopolyploid plants. The study demonstrates that polyploidisation can be crucial for the colonisation of new areas and for range expansion, but it does not necessarily influence elevational distribution nor confer a different phenotype.

2.
Ecol Evol ; 14(2): e10884, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38343575

RESUMEN

Differences in the number of alien plant species in different locations may reflect climatic and other controls that similarly affect native species and/or propagule pressure accompanied with delayed spread from the point of introduction. We set out to examine these alternatives for Himalayan plants, in a phylogenetic framework. We build a database of alien plant distributions for the Himalaya. Focusing on the well-documented regions of Jammu & Kashmir (west) and Bhutan (east) we compare alien and native species for (1) richness patterns, (2) degree of phylogenetic clustering, (3) the extent to which species-poor regions are subsets of species-rich regions and (4) continental and climatic affinities/source. We document 1470 alien species (at least 600 naturalised), which comprise ~14% of the vascular plants known from the Himalaya. Alien plant species with tropical affinities decline in richness with elevation and species at high elevations form a subset of those at lower elevations, supporting location of introduction as an important driver of alien plant richness patterns. Separately, elevations which are especially rich in native plant species are also rich in alien plant species, suggesting an important role for climate (high productivity) in determining both native and alien richness. We find no support for the proposition that variance in human disturbance or numbers of native species correlate with alien distributions. Results imply an ongoing expansion of alien species from low elevation sources, some of which are highly invasive.

3.
Rev. peru. biol. (Impr.) ; 30(4)oct. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1530341

RESUMEN

We present a list of bats collected above 2000 meters in Río Abiseo National Park. Sixteen bat species belonging to the Phyllostomidae and Vespertilionidae families were collected during four expeditions between 1987 and 1990. Twelve species were found within expected altitudinal ranges, but four exceeded their previously reported maximum altitudinal ranges. A comparison with other bat lists from other localities at similar altitudes is presented.


Se presenta una lista de murciélagos colectados por encima de los 2000 m en el Parque Nacional Río Abiseo. Dieciséis especies de murciélagos pertenecientes tanto a las familias Phyllostomidae y Vespertilionidae fueron colectadas durante cuatro expediciones realizadas entre 1987 y 1990. Doce especies fueron encontradas dentro de los rangos altitudinales esperados, pero cuatro excedieron su altitud máxima previamente reportada. Se presenta una comparación con otras listas de murciélagos de otras localidades a altitudes similares.

4.
Microorganisms ; 10(9)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36144339

RESUMEN

The Tibetan Plateau is regarded as the third pole of the earth and is one of the least explored places on the planet. Tibetan hull-less barley (Hordeum vulgare L. var. nudum) is the only cereal crop grown widely in the Tibetan Plateau as a staple food. Extensive and long-term cropping of barley may influence the soil's chemical and biological properties, including microbial communities. However, microbiota associated with hull-less barley is largely unexplored. This study aimed to reveal the composition and diversity of bacterial and fungal communities associated with the hull-less barley at different elevations in the Tibetan Plateau. The core bacterial and fungal taxa of Tibetan hull-less barley were identified, with Bacillaceae, Blastocatellaceae, Comamonadaceae, Gemmatimonadaceae, Planococcaceae, Pyrinomonadaceae, Sphingomonadaceae, and Nitrospiraceae being the most abundant bacterial taxa and Ceratobasidiaceae, Chaetomiaceae, Cladosporiaceae, Didymellaceae, Entolomataceae, Microascaceae, Mortierellaceae, and Nectriaceae being the most abundant fungal taxa (relative abundance > 1%). Both bacterial and fungal diversities of hull-less barley were affected by altitude and soil properties such as total carbon, total nitrogen, and available phosphorus and potassium. Both bacterial and fungal diversities showed a significant negative correlation with altitude, indicating that the lower elevations provide a conducive environment for the survival and maintenance of hull-less barley-associated microbiota. Our results also suggest that the high altitude-specific microbial taxa may play an important role in the adaptation of the hull-less barley to the earth's third pole.

5.
Ecol Evol ; 12(7): e9051, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35813928

RESUMEN

The biodiversity in mountainous ecosystems is high but is threatened by rapid environmental change. Urbanization and other anthropogenic factors in the mountains can affect land use and spatial fragmentation. Moreover, patterns of habitat are closely related to elevation and have a major effect on montane biodiversity. The aim of this study was to analyze the effects of spatial fragmentation on the vertical distribution pattern of bird diversity by characterizing the structure of the bird community, species diversity, and landscape factors at different altitudes. From 2016 to 2019, this study made a four years of continuous monitoring of the breeding birds. The result indicated that Mount Tai harbored a high bird diversity. Bird richness, abundance, and Shannon-Wiener index decreased with latitude in Mount Tai monotonically. Moreover, the structure of bird communities varied along altitudinal gradients, and some special species were supported in different elevational bands due to the environmental filtering. Road density, number of habitat patches, patch density, and the percentage of forest were significantly related to bird diversity. Sufficient habitat and more patches in the low-mountain belt supported higher bird diversity. The middle-mountain belt and high-mountain belt showed contrasting patterns. Our results highlight the effects of on-going urbanization and human activities on montane biodiversity and emphasize the need for artificial habitats in the mountains to be managed.

6.
J Plant Res ; 135(5): 647-658, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35699852

RESUMEN

Elevational changes in vegetation are associated with changes in environmental factors, an example of which is provided by the shade-tolerant Abies mariesii and less shade-tolerant Abies veitchii, which dominate forests at high and low elevations, respectively, in subalpine zones of central Japan. In this study, we sought to establish the factors underlying the differential elevational dominance of these two species from the perspective of sapling growth and survival. It is assumed that the growth and survival of saplings is greater at higher rates of surplus production (the value obtained by subtracting the minimum net production to maintain the current sapling leaf mass from the total net production), as sapling leaf mass gradually declines with time if saplings cannot maintain the current sapling leaf mass, thereby increasing the risk of premature mortality. In this regard, we aimed to verify the following two hypotheses: (1) at low elevations, the surplus production rate of A. veitchii is greater than that of A. mariesii in canopy gaps, and vice versa in the forest understory; and (2) at high elevation, the surplus production rate of A. mariesii is greater than that of A. veitchii in both forest understory and canopy gaps. The results obtained in this study were consistent with our two stated hypotheses. In addition, at the low elevation site, the rate of the growth in height of A. veitchii in canopy gaps was greater than that of A. mariesii, indicating that A. veitchii can dominate after disturbance at low elevations. The findings of this study indicate that the differential elevational distribution of the two Abies species can be attributed to interspecific differences in surplus production rates. We believe that these findings will be useful for predicting changes in the distribution of vegetation in response to climate change.


Asunto(s)
Abies , Árboles , Cambio Climático , Bosques , Hojas de la Planta/fisiología , Árboles/fisiología
7.
Ecol Evol ; 12(3): e8698, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35342618

RESUMEN

High-elevation organisms are expected to evolve physiological adaptations to cope with harsh environmental conditions. Yet, evidence for such adaptive differences, especially compared to closely related lowland taxa occurring along the same elevational gradient, is rare. Revisiting an anecdotal natural history observation by O. Bangs from 1899 and based on new measurements of museum specimens, we confirmed that the high-elevation hermit wood wren (Henicorhina anachoreta) from the Sierra Nevada de Santa Marta, Colombia, has longer, more insulative feathers on the chest and back, than its lower-elevation counterpart the grey-breasted wood wren (H. leucophrys). However, we did not find evidence for the same specializations in subspecies of H. leucophrys that live at high elevations on other elevational gradients in the Colombian Andes, although similar adaptive solutions have arisen in separate mountain systems like the Himalayas. Adaptations in plumage may be associated with the recurrence of elevational species replacements throughout the tropics.

8.
Biodivers Data J ; 10: e79923, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35210920

RESUMEN

Biodiversity monitoring is an important means by which to evaluate management effectiveness and develop sound conservation plans. In this study, 52 cameras were installed in the study area of Tianzhushan to assess wildlife diversity and elevational patterns from 2018 to 2019. In total, 9 541 independent photos were collected within 26 565 camera-days. We analysed the relative abundance index (RAI), activity patterns and seasonal activity rhythms of the five most abundant species at 200-m elevational intervals throughout the study area (elevation range 1 400-2 000 m a.s.l.). Based on RAI results, the activity patterns of the five most abundant species (i.e. Susscrofa, Naemorhedusgriseus, Muntiacusreevesi, Arctonyxcollaris and Capricornismilneedwardsii) were analysed. Amongst the detected wild mammals, Susscrofa had the highest RAI value of 9.91, while the occurrence of Tamiopsswinhoei had the lowest RAI at 0.004. In addition, there were significant differences in species activity during the daytime and night-time. RAI of the ungulate community peaked at the 1 600-1 800 m a.s.l. elevational range, thus showing a mid-elevational peak pattern. Differences in vertical distribution patterns were detected for the five most abundant species. Mainland serows and wild boars preferred mid-elevation habitats (1 600-1 800 m a.s.l.), long-tailed gorals preferred mid- and high altitudes (1 600-2 000 m a.s.l.) elevation habitats and Chinese muntjacs and hog badgers preferred low elevation habitats (1 400-1 600 m a.s.l.). Taken together, this is the first study to reveal the five dominant species activity patterns in Tianzhushan, which is of importance for wildlife conservation.

9.
Animals (Basel) ; 11(12)2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34944340

RESUMEN

The elevational range where montane species live is a key factor of spatial niche partitioning, because the limits of such ranges are influenced by interspecies interaction, abiotic stress, and dispersal barriers. At the regional scale, unimodal distributions of single species along the elevation gradient have often been reported, while discontinuous patterns, such as bimodal distributions, and potential ecological implications have been rarely discussed. Here, we used extensive camera trap records to reveal the elevation distribution of Himalaya blue sheep (Pseudois nayaur) and its co-existence with other ground animal communities along a slope of Baima Snow Mountain, southwest China. The results show that Himalaya blue sheep exhibited a distinctive bimodal distribution along the elevation gradient contrasting the unimodal distributions found for the other ungulates in Baima snow mountain. A first distributional peak was represented by a population habituating in scree habitat around 4100 m, and a second peak was found in the dry-hot valley around 2600 m. The two distinct populations co-existed with disparate animal communities and these assemblages were similar both in the dry and rainy seasons. The extremely low abundance of blue sheep observed in the densely forested belt at mid-elevation indicates that vegetation rather than temperature is responsible for such segregation. The low-elevation population relied highly on Opuntia ficus-indica, an invasive cactus species that colonized the region six hundred years ago, as food resource. Being the only animal that developed a strategy to feed on this spiky plant, we suggest invasive species may have formed new foraging niche to support blue sheep population in lower elevation hot-dry river valleys, resulting in the geographic separation from the original population and a potential morphological differentiation, as recorded. These findings emphasize the important conservation values of role of ecological functions to identify different taxa, and conservation values of apparent similar species of different ecological functions.

10.
J Therm Biol ; 98: 102948, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34016365

RESUMEN

Climate warming may have an impact on invasive species and their ecological consequences. Invasive reptiles, which have temperature-dependent physiology, are expected to be greatly impacted by climate warming, though data supporting this is limited. We investigated the potential impact of a warmer climate on an invasive lizard, Eutropis multifasciata, in Taiwan. A mechanistic model, NicheMapR, was used to simulate the maximum activity time available at three elevations, with varying forest densities, under the current climate and a warmer scenario. The results show that climate warming will provide this species more time for activity in the currently occupied lowland region but not in the mountain areas, which are covered with dense forests. However, if the landscape becomes more open in mountain areas, it will become more suitable for this species and may enable an expansion upslope. Our results show that climate warming has a positive impact on this species, and that landscape's characteristics profoundly modulate its impact and the possibilities for elevational expansion in the future.


Asunto(s)
Cambio Climático , Especies Introducidas , Lagartos/fisiología , Altitud , Animales , Temperatura Corporal , Femenino , Bosques , Masculino , Modelos Teóricos , Suelo , Taiwán , Temperatura
11.
Integr Zool ; 16(2): 202-213, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32961032

RESUMEN

Both natural conditions and anthropogenic factors affect the survivability, distribution, and population density of wildlife. To understand the extent and how these factors drive species distributions, a detailed description of animal movement patterns in natural habitats is needed. In this study, we used satellite telemetry to monitor elevational ranges favored by endangered golden snub-nosed monkeys (Rhinopithecus roxellana), in the Qinling Mountains, central China. We investigated the abundance and distribution of food resources through sampling vegetation quadrats at different elevations and sampled anthropogenic activities using field surveys. Our results indicated that although there was no significant variation in food resources between low- (<1500 m) and middle-elevations (1500-2200 m), monkeys were found most often in areas above 1500 m, where there was less anthropogenic development (e.g. houses and roads); however, monkeys rarely ranged above 2200 m and had limited food availability at this altitude. There was limited human disturbance at this elevation. We suggest that both human activity and ecological constraints (i.e. food resources) have considerable effects on elevational use of R. roxellana in the Qinling Mountains. This study highlights the critical roles these factors can play in shaping the vertical distribution of high-altitude primates. This research provides useful insights for habitat-based conservation plans in which human disturbance management and habitat restoration should be prioritized.


Asunto(s)
Altitud , Distribución Animal/fisiología , Colobinae/fisiología , Actividades Humanas , Animales , China , Femenino , Alimentos , Masculino , Tecnología de Sensores Remotos
12.
Artículo en Inglés | MEDLINE | ID: mdl-31338578

RESUMEN

In the Mediterranean region, a group of unrelated plant species share an unusual deep-red flower color and are pollinated by glaphyrid beetles. Some of these species possess different color morphs, but the mechanisms maintaining this color polymorphism are unknown. The peacock anemone, Anemone pavonina, is a color polymorphic species with red or purple flowers. We investigated the spatial distribution of its color morphs and its potential glaphyrid pollinators, Pygopleurus spp., along an elevational gradient on the southern slopes of Mount Olympus, Greece. We found a correlation between relative proportions of the two color morphs with both elevation and beetle abundance. At low elevations (< 1000 m a.s.l.), beetles were abundant and anemone populations comprised only red flowers. Above a steep transition zone with mixed-colored populations (c. 1000-1300 m) most flowers were purple and beetles were rare. Color-trapping experiments revealed a strong preference for red over other colors in beetles and colorimetric modeling suggests that a simple chromatic mechanism is sufficient to explain their color choices. We thus hypothesize that beetles select for red flowers and that with increasing elevation and decreasing beetle density, other flower visitors (e.g., bees) gain importance as pollinators and select for a different color.


Asunto(s)
Anemone/genética , Escarabajos , Flores/genética , Polinización , Polimorfismo Genético , Animales , Color , Grecia
13.
Ecol Evol ; 9(3): 1289-1305, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30805160

RESUMEN

Climate warming and habitat transformation are widely recognized as worrying threatening factors. Understanding the individual contribution of these two factors to the change of species distribution could be very important in order to effectively counteract the species range contraction, especially in mountains, where alpine species are strongly limited in finding new areas to be colonized at higher elevations. We proposed a method to disentangle the effects of the two drivers of range change for breeding birds in Italian Alps, in the case of co-occurring climate warming and shrub and forest encroachment. For each species, from 1982 to 2017, we related the estimated yearly elevational distribution of birds to the correspondent overall average of the daily minimum temperatures during the breeding season and the estimated amount of shrubs and forest cover. Using a hierarchical partitioning approach, we assessed the net contribution (i.e., without the shared effect) of each driver. Both temperature and shrub and forest cover showed a positive trend along the time series and resulted the most likely causes of the significant elevational displacement for 21 of the 29 investigated birds. While shrub and forest cover was found to be an important driver of the expansion of forest bird range toward higher elevations, the effect of temperature on favouring the colonization of previously climatically unsuitable forests at higher elevations was not negligible. Shrub and forest expansion resulted the main driver of the range contraction for edge and open habitat species, which suffered a distribution shrinkage at their lower elevational boundary. In light of climate warming, these results highlighted how the net range loss for edge and open habitat species, caused by shrub and forest encroachment consequent to land abandonment, should be counteracted by implementing proper conservation management strategies and promoting sustainable economic activities in rangeland areas.

14.
Plant Biol (Stuttg) ; 21(2): 307-317, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30411452

RESUMEN

Climate change will alter the biotic and abiotic environment and dissipate ecological barriers, reorganising maps of current distribution of parasites and their hosts. In this study, we analyse the population dynamics of the parasitic plant Viscum album subsp. austriacum and explore key biotic (host availability and seed dispersal) as well as abiotic (temperature) factors influencing elevational distribution. The study was conducted along an elevational gradient of a Mediterranean mountain, covering the distribution belts of three potential pine hosts: Pinus halepensis (1300-1500 m), P. nigra (1300-1900 m) and P. sylvestris var. nevadensis (1600-2000 m). Along this gradient, we measured multiple variables of mistletoe population (prevalence, abundance and demographic profile) and different factors that might define the current mistletoe distribution (host suitability and availability, temperature and seed dispersal services). We found a decline in mistletoe prevalence and abundance with increasing elevation, detecting larger values of both variables at lower elevations of the most suitable host (Pinus nigra). Pinus sylvestris var. nevadensis was a suboptimal but suitable host for the parasite at high elevations. Mistletoe found suitable temperatures and seed dispersal services all along the gradient, being able to recruit at any site. With warming temperatures, the presence of suitable vectors for parasite dispersion, and the presence of a sub-optimal host (P. sylvestris var. nevadensis) at the mountain top, mistletoe currently has a window of opportunity to expand its present geographic distribution to the summits.


Asunto(s)
Altitud , Interacciones Huésped-Parásitos , Pinus sylvestris/parasitología , Pinus/parasitología , Viscum album/fisiología , Ambiente , Región Mediterránea , Dinámica Poblacional , Dispersión de Semillas/fisiología , Temperatura
15.
Sci Total Environ ; 658: 723-731, 2019 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-30583167

RESUMEN

Archaea play crucial roles in geochemical cycles and influence the emission of greenhouse gases in acidic soils. However, little is known about the distribution pattern of total archaeal diversity and community composition with increasing elevation, especially in acidic agricultural ecosystems. Terraces, characterized by vertical climate changes and unique hydrological properties, are "natural experiments" to explore the spatial distribution of microorganisms along elevation in paddy soils. Here we investigated the diversity and structure of soil archaeal communities in nine increasingly elevated acidic paddy soils of the Yunhe terrace, China. Archaeal communities were dominated by Methanomicrobia of Euryarchaeota (38.5%), Group 1.1a-associated cluster (SAGSCG-1) of Thaumarchaeota (22.0%) and Subgroup-6 (previously described as crenarchaeotal group 1.3b) of Bathyarchaeota (17.8%). The archaeal phylotype richness decreased with increasing elevation. Both the species richness and phylogenetic diversity of the archaeal communities were significantly negatively correlated with soil available phosphorus (AP) content according to linear regression analyses. The archaeal communities differed greatly between soils of increasing elevation, and were roughly clustered into three groups, mostly in relation to AP contents. A variation partitioning analysis further confirmed that edaphic factors including the content of AP (17.1%), nitrate (7.83%), soil organic carbon (4.69%), dissolved organic carbon (4.22%) and soil pH (4.07%) shaped the archaeal community. The variation of soil properties were probably induced by elevation. The co-occurrence network indicated a modular structure of the archaeal community. Overall, our results emphasized that soil AP content was the best predictor of archaeal diversity and community structure, and the impacts of elevation on soil archaeal communities were not diminished by long-term rice cultivation, although minor compared with the effects of soil properties.


Asunto(s)
Archaea/fisiología , Microbiota , Fósforo/análisis , Microbiología del Suelo , Suelo/química , Altitud , Archaea/química , China , Oryza/crecimiento & desarrollo , Análisis Espacial
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