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1.
Nat Commun ; 12(1): 702, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514713

RESUMO

Lima bean (Phaseolus lunatus L.), one of the five domesticated Phaseolus bean crops, shows a wide range of ecological adaptations along its distribution range from Mexico to Argentina. These adaptations make it a promising crop for improving food security under predicted scenarios of climate change in Latin America and elsewhere. In this work, we combine long and short read sequencing technologies with a dense genetic map from a biparental population to obtain the chromosome-level genome assembly for Lima bean. Annotation of 28,326 gene models show high diversity among 1917 genes with conserved domains related to disease resistance. Structural comparison across 22,180 orthologs with common bean reveals high genome synteny and five large intrachromosomal rearrangements. Population genomic analyses show that wild Lima bean is organized into six clusters with mostly non-overlapping distributions and that Mesomerican landraces can be further subdivided into three subclusters. RNA-seq data reveal 4275 differentially expressed genes, which can be related to pod dehiscence and seed development. We expect the resources presented here to serve as a solid basis to achieve a comprehensive view of the degree of convergent evolution of Phaseolus species under domestication and provide tools and information for breeding for climate change resiliency.


Assuntos
Aclimatação/genética , Produtos Agrícolas/genética , Phaseolus/genética , Melhoramento Vegetal , Locos de Características Quantitativas , Argentina , Mapeamento Cromossômico , Mudança Climática , Domesticação , Genes de Plantas/genética , México , Dispersão Vegetal , RNA-Seq , Sementes , Sintenia
2.
Nat Commun ; 12(1): 451, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469023

RESUMO

Changing forest disturbance regimes and climate are driving accelerated tree mortality across temperate forests. However, it remains unknown if elevated mortality has induced decline of tree populations and the ecological, economic, and social benefits they provide. Here, we develop a standardized forest demographic index and use it to quantify trends in tree population dynamics over the last two decades in the western United States. The rate and pattern of change we observe across species and tree size-distributions is alarming and often undesirable. We observe significant population decline in a majority of species examined, show decline was particularly severe, albeit size-dependent, among subalpine tree species, and provide evidence of widespread shifts in the size-structure of montane forests. Our findings offer a stark warning of changing forest composition and structure across the western US, and suggest that sustained anthropogenic and natural stress will likely result in broad-scale transformation of temperate forests globally.


Assuntos
Monitorização de Parâmetros Ecológicos/tendências , Florestas , Dispersão Vegetal , Árvores , Mudança Climática , Conservação dos Recursos Naturais , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Modelos Estatísticos , Análise Espacial , Estados Unidos
3.
Nat Commun ; 12(1): 516, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483517

RESUMO

Understanding how biological and environmental factors interactively shape the global distribution of plant and animal genetic diversity is fundamental to biodiversity conservation. Genetic diversity measured in local populations (GDP) is correspondingly assumed representative for population fitness and eco-evolutionary dynamics. For 8356 populations across the globe, we report that plants systematically display much lower GDP than animals, and that life history traits shape GDP patterns both directly (animal longevity and size), and indirectly by mediating core-periphery patterns (animal fecundity and plant dispersal). Particularly in some plant groups, peripheral populations can sustain similar GDP as core populations, emphasizing their potential conservation value. We further find surprisingly weak support for general latitudinal GDP trends. Finally, contemporary rather than past climate contributes to the spatial distribution of GDP, suggesting that contemporary environmental changes affect global patterns of GDP. Our findings generate new perspectives for the conservation of genetic resources at worldwide and taxonomic-wide scales.


Assuntos
Biodiversidade , Clima , Ecossistema , Variação Genética , Plantas/genética , Algoritmos , Distribuição Animal , Animais , Evolução Molecular , Genética Populacional , Geografia , Traços de História de Vida , Modelos Teóricos , Filogenia , Dispersão Vegetal , Plantas/classificação
4.
Nat Commun ; 12(1): 129, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420082

RESUMO

The recent Californian hot drought (2012-2016) precipitated unprecedented ponderosa pine (Pinus ponderosa) mortality, largely attributable to the western pine beetle (Dendroctonus brevicomis; WPB). Broad-scale climate conditions can directly shape tree mortality patterns, but mortality rates respond non-linearly to climate when local-scale forest characteristics influence the behavior of tree-killing bark beetles (e.g., WPB). To test for these cross-scale interactions, we conduct aerial drone surveys at 32 sites along a gradient of climatic water deficit (CWD) spanning 350 km of latitude and 1000 m of elevation in WPB-impacted Sierra Nevada forests. We map, measure, and classify over 450,000 trees within 9 km2, validating measurements with coincident field plots. We find greater size, proportion, and density of ponderosa pine (the WPB host) increase host mortality rates, as does greater CWD. Critically, we find a CWD/host size interaction such that larger trees amplify host mortality rates in hot/dry sites. Management strategies for climate change adaptation should consider how bark beetle disturbances can depend on cross-scale interactions, which challenge our ability to predict and understand patterns of tree mortality.


Assuntos
Secas , Pinus ponderosa/parasitologia , Doenças das Plantas/parasitologia , Árvores/parasitologia , Gorgulhos/patogenicidade , Animais , California , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Interações Hospedeiro-Parasita/fisiologia , Feromônios/metabolismo , Pinus ponderosa/fisiologia , Casca de Planta/parasitologia , Dispersão Vegetal , Árvores/fisiologia , Água , Gorgulhos/fisiologia
5.
PLoS One ; 15(12): e0243717, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332473

RESUMO

How to increase crop yield is the most important issue in agricultural production. Many studies have been devoted to optimizing spatial distribution of crops, to improve light interception and increase photosynthetic assimilation. However, finding an optimal solution based on field experiments is almost impossible since the large number of combinations of factors that are related, and the cost in terms of finances and time are prohibitive. A new optimization strategy was proposed in this study, integrating a Functional-Structural Model of rice with a workflow based on a Mixed Particle Swarm Optimization (MPSO) algorithm. The 3D modelling platform GroIMP was used to implement the model and optimization workflow. MPSO is a new Particle Swarm Optimization-based algorithm with multistage disturbances, which has improved abilities to get rid of local optima and to explore solution space. Spacing between plants was used as optimization target in the first example. An optimal plant spacing was obtained within the model framework of current environmental settings together with the functional and structural modules. Simulation results indicate that the optimized plant spacing could increase rice yield, and that the optimization results remain stable.


Assuntos
Produção Agrícola/métodos , Produtos Agrícolas/fisiologia , Modelos Teóricos , Oryza/fisiologia , Dispersão Vegetal/fisiologia , Algoritmos , Simulação por Computador , Luz , Fotossíntese/efeitos da radiação , Fluxo de Trabalho
6.
Nat Commun ; 11(1): 5601, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154374

RESUMO

The extent to which species can balance out the loss of suitable habitats due to climate warming by shifting their ranges is an area of controversy. Here, we assess whether highly efficient wind-dispersed organisms like bryophytes can keep-up with projected shifts in their areas of suitable climate. Using a hybrid statistical-mechanistic approach accounting for spatial and temporal variations in both climatic and wind conditions, we simulate future migrations across Europe for 40 bryophyte species until 2050. The median ratios between predicted range loss vs expansion by 2050 across species and climate change scenarios range from 1.6 to 3.3 when only shifts in climatic suitability were considered, but increase to 34.7-96.8 when species dispersal abilities are added to our models. This highlights the importance of accounting for dispersal restrictions when projecting future distribution ranges and suggests that even highly dispersive organisms like bryophytes are not equipped to fully track the rates of ongoing climate change in the course of the next decades.


Assuntos
Briófitas/fisiologia , Mudança Climática , Dispersão Vegetal/fisiologia , Briófitas/classificação , Briófitas/crescimento & desenvolvimento , Ecossistema , Europa (Continente) , Extinção Biológica , Previsões , Modelos Teóricos , Vento
7.
Nat Commun ; 11(1): 4295, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908130

RESUMO

Recent expansion of croplands in the United States has caused widespread conversion of grasslands and other ecosystems with largely unknown consequences for agricultural production and the environment. Here we assess annual land use change 2008-16 and its impacts on crop yields and wildlife habitat. We find that croplands have expanded at a rate of over one million acres per year, and that 69.5% of new cropland areas produced yields below the national average, with a mean yield deficit of 6.5%. Observed conversion infringed upon high-quality habitat that, relative to unconverted land, had provided over three times higher milkweed stem densities in the Monarch butterfly Midwest summer breeding range and 37% more nesting opportunities per acre for waterfowl in the Prairie Pothole Region of the Northern Great Plains. Our findings demonstrate a pervasive pattern of encroachment into areas that are increasingly marginal for production, but highly significant for wildlife, and suggest that such tradeoffs may be further amplified by future cropland expansion.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Custos e Análise de Custo/estatística & dados numéricos , Produção Agrícola/tendências , Produtos Agrícolas/economia , Animais , Biodiversidade , Borboletas , Produção Agrícola/economia , Produção Agrícola/estatística & dados numéricos , Dispersão Vegetal , Análise Espaço-Temporal , Estados Unidos
8.
PLoS One ; 15(6): e0234960, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32603348

RESUMO

Documenting changes in ecosystem extent and protection is essential to understanding status of biodiversity and related ecosystem services and have direct applications to measuring Essential Biodiversity Variables, Targets under the Convention on Biological Diversity (CBD), and IUCN Red List of Ecosystems. We developed both potential and current distribution maps of terrestrial ecosystem types for the temperate and tropical Americas; with "potential" estimating where a type would likely occur today had there not been prior land conversion for modern land uses. We utilized a hierarchical classification to describe and map natural ecosystem types at six levels of thematic detail, with lower thematic levels defining more units each with narrower floristic range than upper levels. Current land use/land cover was derived using available global data on human land use intensity and combined with the potential distribution maps to estimate long-term change in extent for each ecosystem type. We also assessed representation of ecosystem types within protected areas as defined by IUCN I-VI land status categories. Of the 749 ecosystem types assessed, represented at 5th (n = 315) vs. 6th (n = 433) levels of the classification hierarchy, 5 types (1.6%) and 31 types (7.1%), respectively, have lost >90% of their potential extent. Some 66 types (20.9%) and 141 types (32.5%), respectively, have lost >50% of their potential extent; thus, crossing thresholds of Vulnerable status under IUCN Red List criterion A3. For ecosystem type representation within IUCN protected area classes, with reference to potential extent of each type, 111 (45.3%) and 125 (28.8%) of types, respectively, have higher representation (>17%) than CBD 2020 targets. Twelve types (3.8%) and 23 (5.3%) of types, respectively, are represented with <1% within protected areas. We illustrate an option for visualizing and reporting on CBD targets (2020 and proposed post-2020) for ecosystem representativeness using both potential extent as a baseline.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/tendências , Ecologia/métodos , Dispersão Vegetal , América , Conservação dos Recursos Naturais/estatística & dados numéricos , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Monitorização de Parâmetros Ecológicos/tendências , Ecologia/tendências , Floresta Úmida , Clima Tropical
9.
Nat Commun ; 11(1): 3346, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620761

RESUMO

Tropical ecosystems adapted to high water availability may be highly impacted by climatic changes that increase soil and atmospheric moisture deficits. Many tropical regions are experiencing significant changes in climatic conditions, which may induce strong shifts in taxonomic, functional and phylogenetic diversity of forest communities. However, it remains unclear if and to what extent tropical forests are shifting in these facets of diversity along climatic gradients in response to climate change. Here, we show that changes in climate affected all three facets of diversity in West Africa in recent decades. Taxonomic and functional diversity increased in wetter forests but tended to decrease in forests with drier climate. Phylogenetic diversity showed a large decrease along a wet-dry climatic gradient. Notably, we find that all three facets of diversity tended to be higher in wetter forests. Drier forests showed functional, taxonomic and phylogenetic homogenization. Understanding how different facets of diversity respond to a changing environment across climatic gradients is essential for effective long-term conservation of tropical forest ecosystems.


Assuntos
Biodiversidade , Secas , Florestas , Dispersão Vegetal , Plantas/genética , África Ocidental , Biomassa , Mudança Climática , Conservação dos Recursos Naturais , Filogenia , Chuva , Solo/química , Clima Tropical , Água
10.
PLoS One ; 15(6): e0233498, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497043

RESUMO

Distinct zonation of community assemblages among habitats is a ubiquitous feature of coral reefs. The distribution of roving herbivorous fishes (parrotfishes, surgeonfishes and rabbitfishes) is a particularly clear example, with the abundance of these fishes generally peaking in shallow-water, high-energy habitats, regardless of the biogeographic realm. Yet, our understanding of the factors which structure this habitat partitioning, especially with regards to different facets of structural complexity and nutritional resource availability, is limited. To address this issue, we used three-dimensional photogrammetry and structure-from-motion technologies to describe five components of structural complexity (rugosity, coral cover, verticality, refuge density and field-of-view) and nutritional resource availability (grazing surface area) among habitats and considered how these factors are related to herbivorous fish distributions. All complexity metrics (including coral cover) were highest on the slope and crest. Nutritional resource availability differed from this general pattern and peaked on the outer-flat. Unexpectedly, when compared to the distribution of herbivorous fishes, none of the complexity metrics had a marked influence in the models. However, grazing surface area was a strong predictor of both the abundance and biomass of herbivorous fishes. The strong relationship between grazing surface area and herbivorous fish distributions indicates that nutritional resource availability may be one of the primary factors driving the distribution of roving herbivorous fishes. The lack of a relationship between complexity and herbivorous fishes, and a strong affinity of herbivorous fishes for low-complexity, algal turf-dominated outer-flat habitats, offers some cautious optimism that herbivory may be sustained on future, low-complexity, algal turf-dominated reef configurations.


Assuntos
Recifes de Corais , Ecossistema , Peixes/fisiologia , Herbivoria , Distribuição Animal , Animais , Antozoários , Biomassa , Comportamento Alimentar , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Modelos Biológicos , Dispersão Vegetal , Plantas Comestíveis , Propriedades de Superfície , Ondas de Maré
11.
PLoS One ; 15(5): e0232835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32384101

RESUMO

Many plant species harbor communities of symbionts that release nutrients used by their host plants. However, the importance of these nutrients to plant growth and reproductive effort is not well understood. Here, we evaluate the relationship between the communities that colonize pitcher plant phytotelmata and the pitcher plants' vegetative growth and flower production to better understand the symbiotic role played by phytotelma communities. We focus on the mountain variety purple pitcher plant (Sarracenia purpurea var. montana), which occurs in small and isolated populations in Western North Carolina. We found that greater symbiont community diversity is associated with higher flower production the following season. We then examined geographic variation in communities and found that smaller plant populations supported less diverse symbiont communities. We relate our observations to patterns of community diversity predicted by community ecology theory.


Assuntos
Artrópodes/fisiologia , Biota/fisiologia , Sarraceniaceae/crescimento & desenvolvimento , Simbiose/fisiologia , Animais , Biodiversidade , Chironomidae/crescimento & desenvolvimento , Chironomidae/metabolismo , Copépodes/metabolismo , Culicidae/metabolismo , Flores/crescimento & desenvolvimento , Larva , Ácaros/metabolismo , Ciclo do Nitrogênio , Dispersão Vegetal , Folhas de Planta/crescimento & desenvolvimento , Reprodução , Sarraceniaceae/metabolismo
12.
Am Nat ; 195(5): 833-850, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32364792

RESUMO

Global change may induce changes in savanna and forest distributions, but the dynamics of these changes remain unclear. Classical biome theory suggests that climate is predictive of biome distributions, such that shifts will be continuous and reversible. This view, however, cannot explain the overlap in the climatic ranges of tropical biomes, which some argue may result from fire-vegetation feedbacks, maintaining savanna and forest as bistable states. Under this view, biome shifts are argued to be discontinuous and irreversible. Mean-field bistable models, however, are also limited, as they cannot reproduce the spatial aggregation of biomes. Here we suggest that both models ignore spatial processes, such as dispersal, which may be important when savanna and forest abut. We examine the contributions of dispersal to determining biome distributions using a 2D reaction-diffusion model, comparing results qualitatively to empirical savanna and forest distributions in sub-Saharan Africa. We find that the diffusion model resolves both the aforementioned limitations of biome models. First, local dispersive spatial interactions, with an underlying precipitation gradient, can reproduce the spatial aggregation of biomes with a stable savanna-forest boundary. Second, the boundary is determined not only by the amount of precipitation but also by the geometrical shape of the precipitation contours. These geometrical effects arise from continental-scale source-sink dynamics, which reproduce the mismatch between biome and climate. Dynamically, the spatial model predicts that dispersal may increase the resilience of tropical biome in response to global change: the boundary continuously tracks climate, recovering following disturbances, unless the remnant biome patches are too small.


Assuntos
Florestas , Pradaria , Dispersão Vegetal , Clima Tropical , África ao Sul do Saara , Modelos Biológicos
13.
Am Nat ; 195(6): 948-963, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32469653

RESUMO

The causes of the rapid diversification and extraordinary richness of flowering plants (angiosperms) relative to other plant clades is a long-standing mystery. Angiosperms are only one among 10 major land plant clades (phyla) but include ∼90% of land plant species. However, most studies that have tried to identify which traits might explain the remarkable diversification of angiosperms have focused only on richness patterns within angiosperms and tested only one or a few traits at a single hierarchical scale. Here, we assemble a database of 31 diverse traits among 678 families and analyze relationships between traits and diversification rates across all land plants at three hierarchical levels (phylum, order, and family) using phylogenetic multiple regression. We find that most variation (∼85%) in diversification rates among major clades (phyla) is explained by biotically mediated fertilization (e.g., insect pollination) and clade-level geographic range size. Different sets of traits explain diversification at different hierarchical levels, with geographic range size dominating among families. Surprisingly, we find that traits related to local-scale species interactions (i.e., biotic fertilization) are particularly important for explaining diversification patterns at the deepest timescales, whereas large-scale geographic factors (i.e., clade-level range size) are more important at shallower timescales. This dichotomy might apply broadly across organisms.


Assuntos
Especiação Genética , Magnoliopsida/classificação , Polinização , Animais , Biodiversidade , Insetos , Filogenia , Dispersão Vegetal
14.
Proc Natl Acad Sci U S A ; 117(16): 8989-9000, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32238559

RESUMO

The European continent was subject to two major migrations of peoples during the Holocene: the northwestward movement of Anatolian farmer populations during the Neolithic and the westward movement of Yamnaya steppe peoples during the Bronze Age. These movements changed the genetic composition of the continent's inhabitants. The Holocene was also characterized by major changes in vegetation composition, which altered the environment occupied by the original hunter-gatherer populations. We aim to test to what extent vegetation change through time is associated with changes in population composition as a consequence of these migrations, or with changes in climate. Using ancient DNA in combination with geostatistical techniques, we produce detailed maps of ancient population movements, which allow us to visualize how these migrations unfolded through time and space. We find that the spread of Neolithic farmer ancestry had a two-pronged wavefront, in agreement with similar findings on the cultural spread of farming from radiocarbon-dated archaeological sites. This movement, however, did not have a strong association with changes in the vegetational landscape. In contrast, the Yamnaya migration speed was at least twice as fast and coincided with a reduction in the amount of broad-leaf forest and an increase in the amount of pasture and natural grasslands in the continent. We demonstrate the utility of integrating ancient genomes with archaeometric datasets in a spatiotemporal statistical framework, which we foresee will enable future studies of ancient populations' movements, and their putative effects on local fauna and flora.


Assuntos
Arqueologia/métodos , Genoma Humano , Migração Humana/história , Modelos Genéticos , Análise Espaço-Temporal , Agricultura/história , Distribuição Animal , DNA Antigo/análise , Conjuntos de Dados como Assunto , Europa (Continente) , Fazendeiros , Estudos de Viabilidade , Florestas , Geografia , Pradaria , História Antiga , Humanos , Dispersão Vegetal , Datação Radiométrica
15.
Nat Commun ; 11(1): 1695, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32245942

RESUMO

The pattern of species abundance, represented by the number of individuals per species within an ecological community, is one of the fundamental characteristics of biodiversity. However, despite their obvious significance in ecology and biogeography, there is still no clear understanding of these patterns at large spatial scales. Here, we develop a hierarchical modelling approach to estimate macroscale patterns of species abundance. Using this approach, estimates of absolute abundance of 1248 woody plant species at a 10-km-grid-square resolution over East Asian islands across subtropical to temperate biomes are obtained. We provide two examples of the basic and applied use of the estimated species abundance for (1) inference of macroevolutionary processes underpinning regional biodiversity patterns and (2) quantitative community-wide assessment of a national red list. These results highlight the potential of the elucidation of macroscale species abundance that has thus far been an inaccessible but critical property of biodiversity.


Assuntos
Biodiversidade , Evolução Biológica , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Modelos Biológicos , Dispersão Vegetal , Ilhas
16.
Nat Commun ; 11(1): 1243, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144261

RESUMO

Many studies have estimated the adverse effects of climate change on crop yields, however, this literature almost universally assumes a constant geographic distribution of crops in the future. Movement of growing areas to limit exposure to adverse climate conditions has been discussed as a theoretical adaptive response but has not previously been quantified or demonstrated at a global scale. Here, we assess how changes in rainfed crop area have already mediated growing season temperature trends for rainfed maize, wheat, rice, and soybean using spatially-explicit climate and crop area data from 1973 to 2012. Our results suggest that the most damaging impacts of warming on rainfed maize, wheat, and rice have been substantially moderated by the migration of these crops over time and the expansion of irrigation. However, continued migration may incur substantial environmental costs and will depend on socio-economic and political factors in addition to land suitability and climate.


Assuntos
Aclimatação , Mudança Climática , Produção Agrícola/tendências , Produtos Agrícolas/fisiologia , Dispersão Vegetal , Irrigação Agrícola/estatística & dados numéricos , Irrigação Agrícola/tendências , Produção Agrícola/métodos , Produção Agrícola/estatística & dados numéricos , Oryza/fisiologia , Soja/fisiologia , Temperatura , Triticum/fisiologia , Zea mays/fisiologia
17.
Am Nat ; 195(3): 569-576, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32097046

RESUMO

Extinction threatens many species yet is predicted by few factors across the plant tree of life (ToL). Taxon age is one factor that may associate with extinction if occupancy of geographic and adaptive zones varies with time, but evidence for such an association has been equivocal. Age-dependent occupancy can also influence diversification rates and thus extinction risk where new taxa have small range and population sizes. To test how age, diversification, and range size were correlated with extinction, we analyzed 639 well-sampled genera representing 8,937 species from across the plant ToL. We found a greater proportion of species were threatened by contemporary extinction in younger and faster-diversifying genera. When we directly tested how range size mediated this pattern in two large, well-sampled groups, our results varied. In conifers, potential range size was smaller in older species and was correlated with higher extinction risk. Age on its own had no direct effect on extinction when accounting for its influence on range size. In palm species, age was neither directly nor indirectly correlated with extinction risk. Our results suggest that range size dynamics may explain differing patterns of extinction risk across the ToL, with consequences for biodiversity conservation.


Assuntos
Evolução Biológica , Conservação dos Recursos Naturais , Extinção Biológica , Especiação Genética , Dispersão Vegetal , Mudança Climática , Modelos Biológicos , Densidade Demográfica , Especificidade da Espécie
18.
Nat Plants ; 6(2): 78-87, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32055044

RESUMO

Wheat and barley evolved from large-seeded annual grasses in the arid, low latitudes of Asia; their spread into higher elevations and northern latitudes involved corresponding evolutionary adaptations in these plants, including traits for frost tolerance and shifts in photoperiod sensitivity. The adaptation of farming populations to these northern latitudes was also a complex and poorly understood process that included changes in cultivation practices and the varieties of crops grown. In this article, we push back the earliest dates for the spread of wheat and barley into northern regions of Asia as well as providing earlier cultural links between East and West Asia. The archaeobotanical, palynological and anthracological data we present come from the Tongtian Cave site in the Altai Mountains, with a punctuated occupation dating between 5,200 and 3,200 calibrated years BP, coinciding with global cooling of the middle-late Holocene transition. These early low-investment agropastoral populations in the north steppe area played a major role in the prehistoric trans-Eurasian exchange.


Assuntos
Agricultura , Grão Comestível , Hordeum , Dispersão Vegetal , Triticum , Arqueologia , China , Produtos Agrícolas , Migração Humana
19.
Ying Yong Sheng Tai Xue Bao ; 31(1): 97-103, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957385

RESUMO

Vitis heyneana and V. davidii are two wild wine grape varieties that originate from China. In this study, we used the principle of maximum entropy in terms of sufficiency and necessity to identify the dominant climatic factors (among the many climatic factors that were brought up by previous relevant studies) affecting the planting distribution of both varieties in China. Based on the probability of planting distribution determined by the comprehensive effect of these dominant climatic factors, we further analyzed the climatic suitability in China for both wild varieties. The results showed that the four dominant climatic factors affecting the spatial distribution of both varieties were annual sunshine duration, precipitation during the flowering stage in May, annual extreme minimum temperature, and average temperature during the coldest month of January. The optimal wine grape-growing subregions for both varieties were mainly located in the western and southern parts of Hunan, the north-central part of Guangxi, the southeastern part of Guizhou, and the central part of Chongqing. The areas of optimal, suitable, and sub-suitable subregions for planting V. heyneana and V. davidii accounted for 2%, 14%, and 16% of the total area of the research region, respectively. In the optimal/suitable subregions for planting both varieties, annual sunshine duration was between 1200-1800 h, annual extreme minimum temperature was above -8 ℃, average temperature during the coldest month of January was between 2-13 ℃, and monthly precipitation in May was between 110-320 mm.


Assuntos
Vitis , China , Dispersão Vegetal , Temperatura
20.
Sci Rep ; 10(1): 1188, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980639

RESUMO

Global patterns of species and evolutionary diversity in plants are primarily determined by a temperature gradient, but precipitation gradients may be more important within the tropics, where plant species richness is positively associated with the amount of rainfall. The impact of precipitation on the distribution of evolutionary diversity, however, is largely unexplored. Here we detail how evolutionary diversity varies along precipitation gradients by bringing together a comprehensive database on the composition of angiosperm tree communities across lowland tropical South America (2,025 inventories from wet to arid biomes), and a new, large-scale phylogenetic hypothesis for the genera that occur in these ecosystems. We find a marked reduction in the evolutionary diversity of communities at low precipitation. However, unlike species richness, evolutionary diversity does not continually increase with rainfall. Rather, our results show that the greatest evolutionary diversity is found in intermediate precipitation regimes, and that there is a decline in evolutionary diversity above 1,490 mm of mean annual rainfall. If conservation is to prioritise evolutionary diversity, areas of intermediate precipitation that are found in the South American 'arc of deforestation', but which have been neglected in the design of protected area networks in the tropics, merit increased conservation attention.


Assuntos
Biodiversidade , Evolução Biológica , Chuva , Árvores , Clima Tropical , Mudança Climática , Conservação dos Recursos Naturais , Cadeias de Markov , Filogenia , Dispersão Vegetal , América do Sul , Especificidade da Espécie
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