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1.
Oecologia ; 204(4): 833-843, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38573499

RESUMEN

Changes in climate and grazing intensity influence plant-community compositions and their functional structure. Yet, little is known about their possible interactive effects when climate change mainly has consequences during the growing season and grazing occurs off growing season (dormant season grazing). We examined the contribution of trait plasticity to the immediate responses in the functional structure of plant community due to the interplay between these two temporally disjunct drivers. We conducted a field experiment in the northern Mongolian steppe, where climate was manipulated by open-top chambers (OTCs) for two growing seasons, increasing temperature and decreasing soil moisture (i.e., increased aridity), and grazing was excluded for one dormant season between these two growing seasons. We calculated the community-weighted mean (CWM) and the functional diversity (FD) of six leaf traits. Based on a variance partitioning approach, we evaluated how much of the responses in CWM and FD to OTCs and dormant season grazing occur through plasticity. The interactive effect of OTCs and the dormant season grazing were detected only after considering the role of trait plasticity. Overall, OTCs influenced the responses in CWM more than in FD, but the effects of OTCs were much less pronounced where dormant season grazing occurred. Thus, warming (together with decreased soil moisture) and the elimination of dormant season grazing could interact to impact the functional trait structure of plant communities through trait plasticity. Climate change effects should be considered in the context of altered land use, even if temporally disjunct.


Asunto(s)
Cambio Climático , Hojas de la Planta , Estaciones del Año , Herbivoria , Plantas , Pradera , Suelo
3.
Nat Plants ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38609675

RESUMEN

Perennial plants create productive and biodiverse hotspots, known as fertile islands, beneath their canopies. These hotspots largely determine the structure and functioning of drylands worldwide. Despite their ubiquity, the factors controlling fertile islands under conditions of contrasting grazing by livestock, the most prevalent land use in drylands, remain virtually unknown. Here we evaluated the relative importance of grazing pressure and herbivore type, climate and plant functional traits on 24 soil physical and chemical attributes that represent proxies of key ecosystem services related to decomposition, soil fertility, and soil and water conservation. To do this, we conducted a standardized global survey of 288 plots at 88 sites in 25 countries worldwide. We show that aridity and plant traits are the major factors associated with the magnitude of plant effects on fertile islands in grazed drylands worldwide. Grazing pressure had little influence on the capacity of plants to support fertile islands. Taller and wider shrubs and grasses supported stronger island effects. Stable and functional soils tended to be linked to species-rich sites with taller plants. Together, our findings dispel the notion that grazing pressure or herbivore type are linked to the formation or intensification of fertile islands in drylands. Rather, our study suggests that changes in aridity, and processes that alter island identity and therefore plant traits, will have marked effects on how perennial plants support and maintain the functioning of drylands in a more arid and grazed world.

5.
Ecol Evol ; 13(8): e10404, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37546572

RESUMEN

The taxonomic status of the now likely extirpated Korean Peninsula wolf has been extensively debated, with some arguing it represents an independent wolf lineage, Canis coreanus. To investigate the Korean wolf's genetic affiliations and taxonomic status, we sequenced and analysed the genomes of a Korean wolf dated to the beginning of the 20th century, and a captive wolf originally from the Pyongyang Central Zoo. Our results indicated that the Korean wolf bears similar genetic ancestry to other regional East Asian populations, therefore suggesting it is not a distinct taxonomic lineage. We identified regional patterns of wolf population structure and admixture in East Asia with potential conservation consequences in the Korean Peninsula and on a regional scale. We find that the Korean wolf has similar genomic diversity and inbreeding to other East Asian wolves. Finally, we show that, in contrast to the historical sample, the captive wolf is genetically more similar to wolves from the Tibetan Plateau; hence, Korean wolf conservation programmes might not benefit from the inclusion of this specimen.

6.
Sci Rep ; 13(1): 11906, 2023 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-37488160

RESUMEN

The incidence of plague has rebounded in the Americas, Asia, and Africa alongside rapid globalization and climate change. Previous studies have shown local climate to have significant nonlinear effects on plague dynamics among rodent communities. We analyzed an 18-year database of plague, spanning 1998 to 2015, in the foci of Mongolia and China to trace the associations between marmot plague and climate factors. Our results suggested a density-dependent effect of precipitation and a geographic location-dependent effect of temperature on marmot plague. That is, a significantly positive relationship was evident between risk of plague and precipitation only when the marmot density exceeded a certain threshold. The geographical heterogeneity of the temperature effect and the contrasting slopes of influence for the Qinghai-Tibet Plateau (QTP) and other regions in the study (nQTP) were primarily related to diversity of climate and landscape types.


Asunto(s)
Peste , Animales , Peste/epidemiología , Marmota , Mongolia , China/epidemiología , Tibet/epidemiología , Roedores
7.
Science ; 378(6622): 915-920, 2022 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-36423285

RESUMEN

Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that interactions between grazing pressure, climate, soil, and biodiversity are critical to explain the delivery of fundamental ecosystem services across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and species-poor drylands, whereas positive effects of grazing were observed in colder and species-rich areas. Considering interactions between grazing and local abiotic and biotic factors is key for understanding the fate of dryland ecosystems under climate change and increasing human pressure.


Asunto(s)
Biodiversidad , Herbivoria , Ganado , Cambio Climático , Suelo
8.
Zookeys ; 1111: 245-265, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36760846

RESUMEN

To establish the biogeographic affinities of the caddisfly fauna of Mongolia, published records and results of our faunistic studies were analyzed. This study captured more than 47,000 adults collected from 386 locations beside lakes, ponds, streams/rivers, and springs in ten sub-basins of Mongolia using Malaise traps, aerial sweeping, and ultraviolet lights. In total, 201 species have been recorded, and approximately 269 species may occur in Mongolia according to our estimation. In a comparison of species richness for the family level, the Limnephilidae and Leptoceridae were the richest in species. The families Brachycentridae, Glossosomatidae, and Psychomyiidae had low species richness, but they included the most dominant species in terms of abundance and/or the percentage of occurrence in the samples from multiple sub-basins. Comparing the sub-basins, the Selenge had the highest Shannon diversity (H' = 3.3) and the Gobi sub-basin had the lowest (H' = 1.5). According to the Jaccard index of similarity, caddisfly species assemblages of Mongolia's ten sub-basins were divided into two main groups: One group includes the Selenge, Shishkhed, Bulgan, Tes, and Depression of Great Lakes sub-basins; the other group includes the Kherlen, Onon, Khalkh Gol, Valley of Lakes, and Gobi sub-basins. The majority of Mongolian species were composed of East Palearctic taxa, with a small percentage of West Palearctic and Nearctic representatives and an even smaller percentage from the Oriental region, suggesting that the Mongolian Gobi Desert is, and has been, a significant barrier to the distribution of caddisfly species between China and Mongolia.

9.
Zootaxa ; 5026(2): 201-220, 2021 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-34810933

RESUMEN

This paper targets the nearly cosmopolitan weevil subfamily Lixinae. A phylogenetic analysis of one mitochondrial and two nuclear DNA fragments obtained from 87 Lixinae and 49 outgroup terminals strongly supports the monophyly of the subfamily. The molytine tribe Mecysolobini is the likeliest sister group of Lixinae; adults of both taxa share the likely synapomorphic condition of the greatly shortened labial palpi. Phylogenetic relationships within the subfamily are poorly resolved. None of three Lixinae tribes is recovered as monophyletic. The subfamilys oldest dichotomy is formed by a clade of two genera Rhabdorrhynchus plus Pachycerus sister to the rest of the subfamily. The genera Chromonotus, Larinus, Lixus, and Stephanocleonus are recovered as non-monophyletic. The genera Asproparthenis, Chromonotus, and Maximus form a strongly supported clade. The genus Eumecops is the likeliest sister to the clade formed by the genera Stephanocleonus plus Coniocleonus. The cleonine genus Scaphomorphus is a sister to a subset of externally most similar species of the genus Lixus; the same clade likely includes the genus Lixoglyptus not represented in the analysis. As an aside we provide a short summary of active flight in adult Cleonini.


Asunto(s)
Escarabajos , Gorgojos , Animales , ADN , Filogenia , Análisis de Secuencia de ADN , Gorgojos/genética
10.
Sci Rep ; 11(1): 15018, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34294812

RESUMEN

Little is known about the diversity and distribution patterns of moths along latitudinal gradients. We studied macro-moths in Mongolia along an 860 km latitudinal climatic gradient to gain knowledge on community composition, alpha, beta, and gamma diversity as well as underlying factors, which can be used as baseline information for further studies related to climate change. We identified 236 species of moths of ten families. Our study shows that the diversity of moths increased with the latitude, i.e., low species richness in the south and higher richness in the north. Moth community composition changed along the gradient, and we revealed a breakpoint of beta diversity that divided grassland and desert communities. In the desert, beta diversity was driven by species loss (i.e., nestedness), and few tolerant species existed with high abundance. In contrast, in the grassland, beta diversity was driven by species replacement with more unique species, (i.e., species which occurred only in one site). We found the lowest species diversity in the transitional zones dominated by few generalist species such as Agrotis ripae and Anarta trifolii. Low precipitation and an increasing number of grazing goats are drivers of species loss. We suggest different conservation strategies regarding the contrasting patterns of beta diversity in desert and grassland.

11.
Ecol Evol ; 11(11): 6527-6535, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34141237

RESUMEN

River hydrogeomorphology is a major driver shaping biodiversity and community composition. Here, we examine how hydrogeomorphic heterogeneity expressed by Functional Process Zones (FPZs) in river networks is associated with fish assemblage variation. We examined this association in two distinct ecoregions in Mongolia expected to display different gradients of river network hydrogeomorphic heterogeneity. We delineated FPZs by extracting valley-scale hydrogeomorphic variables at 10 km sample intervals in forest steppe (FS) and in grassland (G) river networks. We sampled fish assemblages and examined variation associated with changes in gradients of hydrogeomorphology as expressed by the FPZs. Thus, we examined assemblage variation as patterns of occurrence- and abundance-based beta diversities for the taxonomic composition of assemblages and as functional beta diversity. Overall, we delineated 5 and 6 FPZs in river networks of the FS and G, respectively. Eight fish species were found in the FS river network and seventeen in the G, four of them common to both ecoregions. Functional richness was correspondingly higher in the G river network. Variation in the taxonomic composition of assemblages was driven by species turnover and was only significant in the G river network. Abundance-based taxonomic variation was significant in river networks of both ecoregions, while the functional beta diversity results were inconclusive. We show that valley-scale hydrogeomorphology is a significant driver of variation in fish assemblages at a macrosystem scale. Both changes in the composition of fish assemblages and the carrying capacity of the river network were driven by valley-scale hydrogeomorphic variables. River network hydrogeomorphology as accounted for in the study has, therefore, the potential to inform macrosystem scale community ecology research and conservation efforts.

12.
Zootaxa ; 5081(4): 451-482, 2021 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-35390998

RESUMEN

New data on the distribution, bionomy, and taxonomy of the longhorned beetles that occur in the poorly studied region of southeastern Mongolia (mngovi, Dornogovi, and Skhbaatar aimags) are presented together with a list of all taxa that are known from this area. The literature records for all known species from this area were summarized, verified, and mapped. Chlorophorus caragana Xie Wang, 2012 is recorded from Mongolia for the first time. New localities of some little-known taxa that are endemic to Mongolia and adjacent territories, such as Anoplistes halodendri minutus Hammarstrm, 1892, Anoplistes kaszabi Karpiski, 2020, and Eodorcadion gorbunovi Danilevsky, 2004 are given. High-quality stacked images of several unique species, e.g., Anoplistes gobiensis (Namkhaidorzh, 1973), Ch. caragana, and Chlorophorus obliteratus (Ganglbauer, 1889) are presented for the first time along with photographs of their habitats. New remarks on highly complex taxonomic issues concerning some species in the genera Anoplistes, Chlorophorus, and Eodorcadion are also provided.


Asunto(s)
Escarabajos , Animales , Ecosistema , Mongolia
13.
Microb Ecol ; 79(2): 420-431, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31273405

RESUMEN

The soil fungal ecology of the southern Gobi region of Mongolia has been little studied. We utilized the ITS1 region from soil DNA to study possible influences soil metal concentrations on soil fungal community variation. In the sample network, a distinctive fungal community was closely associated with high zinc (Zn), lead (Pb), and copper (Cu) concentrations. The pattern of occurrence suggests that high metal concentrations are natural and not a product of mining activities. The metal-associated fungal community differs little from the "normal" community in its major OTUs, and in terms of major fungal guilds and taxa, and its distinctiveness depends on a combination of many less common OTUs. The fungal community in the sites with high metal concentrations is no less diverse than that in areas with normal background levels. Overall, these findings raise interesting questions of the evolutionary origin and functional characteristics of this apparently "metal-tolerant" community, and of the associated soil biota in general. It is possible that rehabilitation of metal-contaminated mined soils from spoil heaps could benefit from the incorporation of fungi derived from these areas.


Asunto(s)
Micobioma/efectos de los fármacos , Microbiología del Suelo , Contaminantes del Suelo/análisis , Suelo/química , Cobre/análisis , Clima Desértico , Hongos/clasificación , Hongos/aislamiento & purificación , Plomo/análisis , Mongolia , Zinc/análisis
14.
Zookeys ; 853: 87-108, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31217719

RESUMEN

The bio-geographical composition and spatial distribution patterns of dytiscid assemblages in Mongolia are relatively unexplored. In this study, we compiled a list of 99 dytiscid species belonging to 20 genera and five subfamilies recorded in Mongolia and investigated species richness, spatial distribution and bio-geographical composition of the Mongolian dytiscid fauna. This study encompasses the information of currently recorded species and their geographic localities in Mongolia based on our own data and literature sources. We examined how dytiscid species richness was related to sub-basins of surface water network, as well as to geographical elevations within Mongolia. The majority of the Mongolian dytiscid fauna was associated with the sub-basins belonging to Arctic Ocean (80 species, 80.8%) and Central Asian Inland (60 species, 60.6%) basins. Only a few species of dytiscids belonged to the remaining river basins. Species richness of dytiscids and total area of sub-basins were not correlated, but species composition of dytiscids differed significantly among the sub-basins. We observed that most of the species (77 species or 77.8% of total fauna) were recorded in a wide range of elevations and mid-altitudes (1000-2000 m a.s.l.) and showed the greatest diversity of dytiscids. Regarding the bio-geographical composition, species with wide geographical distributions (27.3% of dytiscids), were Palearctic species, while species of Arctic origin (21.2%) together with Boreal elements (16.2%) comprised a large proportion of the dytiscid fauna in Mongolia.

15.
PLoS One ; 14(6): e0217772, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31163047

RESUMEN

The Mongolian Gobi-Eastern Steppe Ecosystem is one of the largest remaining natural drylands and home to a unique assemblage of migratory ungulates. Connectivity and integrity of this ecosystem are at risk if increasing human activities are not carefully planned and regulated. The Gobi part supports the largest remaining population of the Asiatic wild ass (Equus hemionus; locally called "khulan"). Individual khulan roam over areas of thousands of square kilometers and the scale of their movements is among the largest described for terrestrial mammals, making them particularly difficult to monitor. Although GPS satellite telemetry makes it possible to track animals in near-real time and remote sensing provides environmental data at the landscape scale, remotely collected data also harbors the risk of missing important abiotic or biotic environmental variables or life history events. We tested the potential of animal born camera systems ("camera collars") to improve our understanding of the drivers and limitations of khulan movements. Deployment of a camera collar on an adult khulan mare resulted in 7,881 images over a one-year period. Over half of the images showed other khulan and 1,630 images showed enough of the collared khulan to classify the behaviour of the animals seen into several main categories. These khulan images provided us with: i) new insights into important life history events and grouping dynamics, ii) allowed us to calculate time budgets for many more animals than the collared khulan alone, and iii) provided us with a training dataset for calibrating data from accelerometer and tilt sensors in the collar. The images also allowed to document khulan behaviour near infrastructure and to obtain a day-time encounter rate between a specific khulan with semi-nomadic herders and their livestock. Lastly, the images allowed us to ground truth the availability of water by: i) confirming waterpoints predicted from other analyses, ii) detecting new waterpoints, and iii) compare precipitation records for rain and snow from landscape scale climate products with those documented by the camera collar. We discuss the added value of deploying camera collars on a subset of animals in remote, highly variable ecosystems for research and conservation.


Asunto(s)
Ecosistema , Equidae/fisiología , Sistemas de Información Geográfica , Fotograbar/instrumentación , Tecnología de Sensores Remotos , Animales , Conducta Animal/fisiología , Ritmo Circadiano/fisiología , Geografía , Humanos , Procesamiento de Imagen Asistido por Computador , Ganado , Mongolia , Lluvia , Especificidad de la Especie , Agua
16.
Cell ; 177(6): 1419-1435.e31, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-31056281

RESUMEN

Horse domestication revolutionized warfare and accelerated travel, trade, and the geographic expansion of languages. Here, we present the largest DNA time series for a non-human organism to date, including genome-scale data from 149 ancient animals and 129 ancient genomes (≥1-fold coverage), 87 of which are new. This extensive dataset allows us to assess the modern legacy of past equestrian civilizations. We find that two extinct horse lineages existed during early domestication, one at the far western (Iberia) and the other at the far eastern range (Siberia) of Eurasia. None of these contributed significantly to modern diversity. We show that the influence of Persian-related horse lineages increased following the Islamic conquests in Europe and Asia. Multiple alleles associated with elite-racing, including at the MSTN "speed gene," only rose in popularity within the last millennium. Finally, the development of modern breeding impacted genetic diversity more dramatically than the previous millennia of human management.


Asunto(s)
Caballos/genética , Animales , Asia , Evolución Biológica , Cruzamiento/historia , ADN Antiguo/análisis , Domesticación , Equidae/genética , Europa (Continente) , Femenino , Variación Genética/genética , Genoma/genética , Historia Antigua , Masculino , Filogenia
19.
Ecol Evol ; 8(11): 5267-5278, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29938051

RESUMEN

Global climate change is affecting and will continue to affect ecosystems worldwide. Specifically, temperature and precipitation are both expected to shift globally, and their separate and interactive effects will likely affect ecosystems differentially depending on current temperature, precipitation regimes, and other biotic and environmental factors. It is not currently understood how the effects of increasing temperature on plant communities may depend on either precipitation or where communities lie on soil moisture gradients. Such knowledge would play a crucial role in increasing our predictive ability for future effects of climate change in different systems. To this end, we conducted a multi-factor global change experiment at two locations, differing in temperature, moisture, aspect, and plant community composition, on the same slope in the northern Mongolian steppe. The natural differences in temperature and moisture between locations served as a point of comparison for the experimental manipulations of temperature and precipitation. We conducted two separate experiments, one examining the effect of climate manipulation via open-top chambers (OTCs) across the two different slope locations, the other a factorial OTC by watering experiment at one of the two locations. By combining these experiments, we were able to assess how OTCs impact plant productivity and diversity across a natural and manipulated range of soil moisture. We found that warming effects were context dependent, with the greatest negative impacts of warming on diversity in the warmer, drier upper slope location and in the unwatered plots. Our study is an important step in understanding how global change will affect ecosystems across multiple scales and locations.

20.
Nature ; 557(7705): 418-423, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29743673

RESUMEN

Hepatitis B virus (HBV) is a major cause of human hepatitis. There is considerable uncertainty about the timescale of its evolution and its association with humans. Here we present 12 full or partial ancient HBV genomes that are between approximately 0.8 and 4.5 thousand years old. The ancient sequences group either within or in a sister relationship with extant human or other ape HBV clades. Generally, the genome properties follow those of modern HBV. The root of the HBV tree is projected to between 8.6 and 20.9 thousand years ago, and we estimate a substitution rate of 8.04 × 10-6-1.51 × 10-5 nucleotide substitutions per site per year. In several cases, the geographical locations of the ancient genotypes do not match present-day distributions. Genotypes that today are typical of Africa and Asia, and a subgenotype from India, are shown to have an early Eurasian presence. The geographical and temporal patterns that we observe in ancient and modern HBV genotypes are compatible with well-documented human migrations during the Bronze and Iron Ages1,2. We provide evidence for the creation of HBV genotype A via recombination, and for a long-term association of modern HBV genotypes with humans, including the discovery of a human genotype that is now extinct. These data expose a complexity of HBV evolution that is not evident when considering modern sequences alone.


Asunto(s)
Evolución Molecular , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/virología , Filogenia , África , Animales , Asia , Europa (Continente) , Genotipo , Virus de la Hepatitis B/clasificación , Historia Antigua , Historia Medieval , Hominidae/virología , Migración Humana/historia , Humanos , Recombinación Genética
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