scholarly journals Genetic variation and cryptic lineage diversity of the Nigerian red-headed rock agama Agama agama associate with eco-geographic zones

2019 ◽  
Vol 65 (6) ◽  
pp. 713-724 ◽  
Author(s):  
Lotanna M Nneji ◽  
Adeniyi C Adeola ◽  
Fang Yan ◽  
Agboola O Okeyoyin ◽  
Ojo C Oladipo ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Geographic Distance ◽  
Climatic Conditions ◽  
Population Divergence ◽  
Geographic Isolation ◽  
Genetic Structuring ◽  
Derived Savanna ◽  
Wide Range ◽  
Conservation Actions ◽  
The Impact

AbstractNigeria is an Afrotropical region with considerable ecological heterogeneity and levels of biotic endemism. Among its vertebrate fauna, reptiles have broad distributions, thus, they constitute a compelling system for assessing the impact of ecological variation and geographic isolation on species diversification. The red-headed rock agama, Agama agama, lives in a wide range of habitats and, thus, it may show genetic structuring and diversification. Herein, we tested the hypothesis that ecology affects its genetic structure and population divergence. Bayesian inference phylogenetic analysis of a mitochondrial DNA (mtDNA) gene recovered four well-supported matrilines with strong evidence of genetic structuring consistent with eco-geographic regions. Genetic differences among populations based on the mtDNA also correlated with geographic distance. The ecological niche model for the matrilines had a good fit and robust performance. Population divergence along the environmental axes was associated with climatic conditions, and temperature ranked highest among all environmental variables for forest specialists, while precipitation ranked highest for the forest/derived savanna, and savanna specialists. Our results cannot reject the hypothesis that niche conservatism promotes geographic isolation of the western populations of Nigerian A. agama. Thus, ecological gradients and geographic isolation impact the genetic structure and population divergence of the lizards. This species might be facing threats due to recent habitat fragmentation, especially in western Nigeria. Conservation actions appear necessary.

Climate Change Impacts and Adaptations: New Challenges for the Wine Industry

2016 ◽  
Vol 11 (1) ◽  
pp. 139-149 ◽  
Author(s):  
Nathalie Ollat ◽  
Jean-Marc Touzard ◽  
Cornelis van Leeuwen
Keyword(s):  
Climate Change ◽  
Climate Change Impacts ◽  
Climatic Conditions ◽  
Wine Industry ◽  
Adaptation To Climate Change ◽  
Wine Quality ◽  
Wine Production ◽  
Wine Making ◽  
Wide Range ◽  
The Impact

AbstractClimate change will have a profound effect on vine growing worldwide. Wine quality will also be affected, which will raise economic issues. Possible adaptations may result from changes in plant material, viticultural techniques, and the wine-making process. Relocation of vineyards to cooler areas and increased irrigation are other options, but they may result in potential conflicts for land and water use. Grapes are currently grown in many regions around the world, and growers have adapted their practices to the wide range of climatic conditions that can be found among or inside these areas. This knowledge is precious for identifying potential adaptations to climate change. Because climate change affects all activities linked to wine production (grape growing, wine making, wine economics, and environmental issues), multidisciplinary research is needed to guide growers to continue to produce high-quality wines in an economical and environmentally sustainable way. An example of such an interdisciplinary study is the French LACCAVE (long-term adaptation to climate change in viticulture and enology) project, in which researchers from 23 institutes work together on all issues related to the impact of climate change on wine production. (JEL Classifications: Q1, Q5)

Systematic Assessment of Combustion Turbine Inlet Air-Cooling Techniques

2005 ◽  
Vol 127 (1) ◽  
pp. 159-169 ◽  
Author(s):  
Abdalla M. Al-Amiri ◽  
Montaser M. Zamzam
Keyword(s):  
Air Temperature ◽  
Evaporative Cooling ◽  
Heat Rate ◽  
Climatic Conditions ◽  
Coefficient Of Performance ◽  
Air Cooling ◽  
Cooling Systems ◽  
Turbine Inlet ◽  
Wide Range ◽  
The Impact

The current study is centered on assessing the benefits of incorporating combustion turbine inlet air-cooling systems into a reference combustion turbine plant, which is based on a simple cycle under base load mode. Actual climatic conditions of a selected site were examined thoroughly to identify the different governing weather patterns. The main performance characteristics of both refrigerative and evaporative cooling systems were explored by examining the effect of several parameters including inlet air temperature, airflow-to-turbine output ratio, coefficient of performance (for refrigerative cooling systems), and evaporative degree hours (for evaporative cooling systems). The impact of these parameters was presented against the annual gross energy increase, average heat rate reduction, cooling load requirements and net power increase. Finally, a feasibility design chart was constructed to outline the economic returns of employing a refrigerative cooling unit against different prescribed inlet air temperature values using a wide range of combustion turbine mass flow rates.

scholarly journals High levels of genetic diversity and an absence of genetic structure among breeding populations of the endangered Rufous-backed Bunting in Inner Mongolia, China: implications for conservation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shi Li ◽  
Dan Li ◽  
Lishi Zhang ◽  
Weiping Shang ◽  
Bo Qin ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Mitochondrial Dna ◽  
Genetic Structure ◽  
Endangered Species ◽  
Habitat Loss ◽  
Inner Mongolia ◽  
Avian Species ◽  
Genetic Structuring ◽  
Breeding Populations ◽  
The Impact

Abstract Background The Rufous-backed Bunting, Emberiza jankowskii, is an endangered species that is primarily distributed in Inner Mongolia, China. The main threats to the continued persistence of this species are habitat loss and degradation. However, the impact of population loss on genetic diversity remains unclear. To support future conservation and management efforts, we assessed the genetic diversity and population structure of E. jankowskii using mitochondrial DNA and microsatellites. Methods Blood samples were collected from 7‒8-day-old nestlings in Inner Mongolia, China between May and August of 2012 and 2013. Mitochondrial DNA sequences and microsatellite markers were used to assess the genetic diversity, genetic structure and inbreeding of E. jankowskii. The results of genetic diversity and inbreeding were compared to other avian species. Results We found an unexpectedly high level of genetic diversity in terms of mitochondrial DNA and microsatellite compared to other avian species. However, there were high levels of gene flow and minimal genetic structuring, among the fragmented breeding populations of E. jankowskii in Inner Mongolia. These findings suggest that E. jankowskii in Inner Mongolia is a metapopulation. Despite the high genetic diversity of E. jankowskii, local populations in each small patch remain at risk of extinction due to habitat loss. In addition, the E. jankowskii population has a high risk of inbreeding. Conclusions To minimize further loss of genetic diversity of this endangered species, we suggest that the E. jankowskii in Inner Mongolia should be considered as a protected species for management purposes. Conservation efforts should concentrate on E. jankowskii habitat management. This may be most effectively achieved by protecting the current breeding habitats and prohibiting over-grazing.

scholarly journals Environmental factors influence on leeches distribution in the middle reaches of the Irtysh River

2020 ◽  
Vol 9 (4) ◽  
pp. 159-164
Author(s):  
Lyudmila Ivanovna Fedorova
Keyword(s):  
Natural Waters ◽  
Metallurgical Industry ◽  
Climatic Conditions ◽  
Ecological Niches ◽  
Landscape Characteristics ◽  
Industrial Enterprises ◽  
Wide Range ◽  
Irtysh River ◽  
The Impact ◽  
The Irtysh River

The Irtysh River is a transboundary watercourse that exhibits a wide range of climatic conditions, environments and ecological niches. As a result of the technogenic impact of industrial enterprises on surface and underground waters all the main tributaries of the middle reaches of the river Irtysh are in different degrees of pollution. Due to the impact of sewage and other wastes from the mining and metallurgical industry, in the waters of the river basin Irtysh the concentration excess of a number of toxic metals is observed. Among the invertebrates used to assess the state of natural waters, representatives of the Annelida type are often used. Since annelids are among the most common organisms on Earth, this makes it possible to study them in many regions and to assess the specificity of the impact and compare the impact of various pollutants in similar natural and climatic zones. It is known that the distribution of freshwater leeches is largely determined by natural and climatic conditions, landscape characteristics and the specifics of trophic connections, etc. In this case, the most important parameters are the physicochemical properties of water. This paper provides information on the factors influencing the species composition and structural indicators of leech communities living in the middle reaches of the Irtysh River.

scholarly journals Genomic Adaptive Evolution of Sand Rice (Agriophyllum squarrosum) and Its Implications for Desert Ecosystem Restoration

2021 ◽  
Vol 12 ◽  
Author(s):  
Chaoju Qian ◽  
Xia Yan ◽  
Tingzhou Fang ◽  
Xiaoyue Yin ◽  
Shanshan Zhou ◽  
...  
Keyword(s):  
Genetic Structure ◽  
Balancing Selection ◽  
Desert Ecosystem ◽  
Ecological Niches ◽  
Population Divergence ◽  
Desert Plants ◽  
Agriophyllum Squarrosum ◽  
Heterogeneous Habitats ◽  
Wide Range ◽  
Sand Rice

Natural selection is a significant driver of population divergence and speciation of plants. Due to local adaptation to geographic regions with ecological gradients, plant populations harbored a wide range of adaptive genetic variation to enable them to survive the heterogeneous habitats. This is all the more necessary for desert plants, as they must tolerant more striking gradients of abiotic stresses. However, the genomic mechanism by which desert plants adapt to ecological heterogeneity remains unclear, which could help to guide the sustainability of desert ecosystems. Here, using restriction-site-associated DNA sequencing in 38 natural populations, we investigated the genomic divergence and environmental adaptation of sand rice, Agriophyllum squarrosum, an annual pioneer species that covers sand dunes in northern China. Population genetic structure analyses showed that sand rice could be divided into three geographically distinct lineages, namely, Northwest, Central, and East. Phylogeographic analyses revealed that the plant might originate locally in Bergen County and further differentiated into the East lineage and then the Central lineage. Ecological niche modeling found that different lineages occupied distinct ecological niches, suggesting that the ecological gradient would have triggered genomic differentiation among sand rice lineages. Ecological association study supported that the three SNPs under divergent selection were closely correlated with precipitation gradients, indicating that precipitation might be the most important stress trigger for lineage diversity in sand rice. These adaptive SNPs could be used to genotype suitable germplasms for the ecological restoration of specific desertified lands. Further analyses found that genetic structure could significantly overestimate the signals for balancing selection. Within the Central lineage, we still found that 175 SNPs could be subject to balancing selection, which could be the means by which sand rice maintains genetic diversity and adapts to multiple stresses across heterogeneous deserts and sandy lands. From a genomic point of view, this study highlighted the local and global adaptation patterns of a desert plant to extreme and heterogeneous habitats. Our data provide molecular guidance for the restoration of desertified lands in the arid and semi-arid regions of China and could facilitate the marker assistant breeding of this potential crop to mitigate climate change.

scholarly journals Modifications of Grapevine Berry Composition Induced by Main Viral and Fungal Pathogens in a Climate Change Scenario

2021 ◽  
Vol 12 ◽  
Author(s):  
Markus Rienth ◽  
Nicolas Vigneron ◽  
Robert P. Walker ◽  
Simone Diego Castellarin ◽  
Crystal Sweetman ◽  
...  
Keyword(s):  
Climate Change ◽  
Climatic Conditions ◽  
Grape Berry ◽  
Economic Losses ◽  
Future Research ◽  
Change Scenario ◽  
Berry Quality ◽  
Wide Range ◽  
Grapevine Berry ◽  
The Impact

The grapevine is subject to high number of fungal and viral diseases, which are responsible for important economic losses in the global wine sector every year. These pathogens deteriorate grapevine berry quality either directly via the modulation of fruit metabolic pathways and the production of endogenous compounds associated with bad taste and/or flavor, or indirectly via their impact on vine physiology. The most common and devastating fungal diseases in viticulture are gray mold, downy mildew (DM), and powdery mildew (PM), caused, respectively by Botrytis cinerea, Plasmopara viticola, and Erysiphe necator. Whereas B. cinerea mainly infects and deteriorates the ripening fruit directly, deteriorations by DM and PM are mostly indirect via a reduction of photosynthetic leaf area. Nevertheless, mildews can also infect berries at certain developmental stages and directly alter fruit quality via the biosynthesis of unpleasant flavor compounds that impair ultimate wine quality. The grapevine is furthermore host of a wide range of viruses that reduce vine longevity, productivity and berry quality in different ways. The most widespread virus-related diseases, that are known nowadays, are Grapevine Leafroll Disease (GLRD), Grapevine Fanleaf Disease (GFLD), and the more recently characterized grapevine red blotch disease (GRBD). Future climatic conditions are creating a more favorable environment for the proliferation of most virus-insect vectors, so the spread of virus-related diseases is expected to increase in most wine-growing regions. However, the impact of climate change on the evolution of fungal disease pressure will be variable and depending on region and pathogen, with mildews remaining certainly the major phytosanitary threat in most regions because their development rate is to a large extent temperature-driven. This paper aims to provide a review of published literature on most important grapevine fungal and viral pathogens and their impact on grape berry physiology and quality. Our overview of the published literature highlights gaps in our understanding of plant-pathogen interactions, which are valuable for conceiving future research programs dealing with the different pathogens and their impacts on grapevine berry quality and metabolism.

Researches of Advanced Thermal Insulating Materials for Improving the Building Energy Efficiency

2016 ◽  
Vol 683 ◽  
pp. 617-625
Author(s):  
Maxim Morozov ◽  
Pavel A. Strizhak
Keyword(s):  
Energy Efficiency ◽  
Thermal Characteristics ◽  
Temperature Oscillation ◽  
Complex Model ◽  
Climatic Conditions ◽  
Building Energy Efficiency ◽  
Insulation Materials ◽  
Thermal Insulating ◽  
Wide Range ◽  
The Impact

A complex model of building was developed by using Matlab. The model allows conducting for a wide range of research related to improving the energy efficiency of buildings. In this work the investigations of energy efficiency of several advanced insulation materials, which is characterized by different thermal characteristics, were carried out. Conclusions about the impact of the thermal protective envelope on the room thermal regime were made. Prognostic heat consumptions values of rooms with different characteristics of thermal insulation materials and main base-load envelopes were determined. Researches were conducted for the winter climatic conditions of Western Siberia: the average daily outdoor temperatures are -22 °C and -12 °C, the amplitude of temperature oscillation is 8 °C

Population genetic structure of the western spotted frog, Heleioporus albopunctatus (Anura:Myobatrachidae), in a fragmented landscape in south-western Australia

2005 ◽  
Vol 53 (3) ◽  
pp. 167 ◽  
Author(s):  
Robert A. Davis ◽  
J. Dale Roberts
Keyword(s):  
Western Australia ◽  
Geographic Distance ◽  
Significant Degree ◽  
Mantel Test ◽  
Fragmented Landscape ◽  
Significant Determinant ◽  
Geographic Isolation ◽  
Genetic Structuring ◽  
Cellulose Acetate Electrophoresis ◽  
Scaling Analyses

We report on the genetic structuring of populations of a large burrowing frog, Heleioporus albopunctatus, from the central wheatbelt of Western Australia. This region has been highly fragmented by vegetation clearance for agriculture since the early 1900s. Genetic variation at four variable loci in 22 populations was analysed using cellulose acetate electrophoresis. Analysis across all populations showed a moderate, but significant, degree of subdivision (Fst = 0.087 ± 0.049, P < 0.05) and high levels of heterozygosity (H = 0.133, s.e. = 0.084). Several small populations had higher Fst values in pair-wise comparisons. A mantel test revealed no significant relationship between genetic distance and geographic distance (r = –0.136, P = 0.34) and this, combined with data from multidimensional scaling analyses, suggests that geographic isolation of populations is not a significant determinant of genetic structuring. Despite this, the presence of high levels of subdivision as a result of the erosion of genetic diversity indicates that regional persistence may be dependent on the maintenance of metapopulation structures that allow gene flow.

scholarly journals Looking through glassfish: marine genetic structure in an estuarine species

2008 ◽  
Vol 59 (7) ◽  
pp. 627 ◽  
Author(s):  
Courtenay E. Mills ◽  
Wade L. Hadwen ◽  
Jane M. Hughes
Keyword(s):  
Genetic Structure ◽  
Isolation By Distance ◽  
New South ◽  
Geographic Distance ◽  
Genetic Structuring ◽  
The North ◽  
South Wales ◽  
High Dispersal ◽  
Eastern Australia ◽  
Atp8 Gene

Through the use of mitochondrial DNA (ATP8 gene), the prediction of intermediate genetic structuring was investigated in two species of estuarine glassfish (Ambassis marianus and Ambassis jacksoniensis) (Perciformes : Ambassidae) to determine the possibility of a generalised ‘estuarine’ genetic structure. Individuals were collected from estuaries in eastern Australia between Tin Can Bay (Queensland) in the north and Kempsey (New South Wales) in the south. Analysis of the haplotype frequencies found in this region suggested panmictic populations with star-like phylogenies with extremely high levels of genetic diversity, but with no correlation between geographic distance and genetic distance. Non-significant FST and ΦST suggested extensive dispersal among estuaries. However, Tajima’s D and Fu’s FS values suggest ‘mutation–genetic drift equilibrium’ has not been reached, and that population expansions occurring 262 000 (A. marianus) and 300 000 (A. jacksoniensis) years ago may obscure any phylogeographic structuring or isolation by distance. The finding of panmixia was contrary to the prediction of genetic structuring intermediate between that of marine fish (shallowly structured) and freshwater fish (highly structured), suggesting high dispersal capabilities in these species.

scholarly journals Environmental differences explain subtle yet detectable genetic structure in a widespread pollinator

2021 ◽  
Author(s):  
Marcel Glück ◽  
Julia C. Geue ◽  
Henri A. Thomassen
Keyword(s):  
Genetic Structure ◽  
Geographic Distance ◽  
Natural Populations ◽  
Environmental Data ◽  
Genetic Connectivity ◽  
Population Divergence ◽  
Bumble Bee ◽  
Bayesian Clustering ◽  
Holistic Understanding ◽  
Isolation By Environment

Background: The environment is a strong driver of genetic structure in many natural populations, yet often neglected in population genetic studies. This may be a particular problem in vagile species, where subtle structure cannot be explained by limitations to dispersal. These species might falsely be considered panmictic and hence potentially mismanaged. Here we analysed the genetic structure in an economically important and widespread pollinator, the buff-tailed bumble bee (Bombus terrestris), which is considered to be quasi-panmictic at mainland continental scales. We first quantified population structure in Romania and Bulgaria with spatially implicit Fst and Bayesian clustering analyses. We then incorporated environmental information to infer the influence of the permeability of the habitat matrix between populations (resistance distances) as well as environmental differences among sites in explaining population divergence. Results: Genetic structure of the buff-tailed bumble bee was subtle and not detected by Bayesian clustering. As expected, geographic distance and habitat permeability were not informative in explaining the spatial pattern of genetic divergence. Yet, environmental variables related to temperature, vegetation and topography were highly informative, explaining between 33 and 39% of the genetic variation observed. Conclusions: Where in the past spatially implicit approaches had repeatedly failed, incorporating environmental data proved to be highly beneficial in detecting and unravelling the drivers of genetic structure in this vagile and opportunistic species. Indeed, structure followed a pattern of isolation by environment, where the establishment of dispersers is limited by environmental differences among populations, resulting in the disruption of genetic connectivity and the divergence of populations through genetic drift and divergent natural selection. With this work, we highlight the potential of incorporating environmental differences among population locations to complement the more traditional approach of isolation by geographic distance, in order to obtain a holistic understanding of the processes driving structure in natural populations.

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