Global associations between terrestrial producer and vertebrate consumer diversity

In both ecology and conservation, often a strong positive association is assumed between the diversity of plants as primary producers and that of animals, specifically primary consumers. Such a relationship has been observed at small spatial scales, and a begetting of diversity by diversity is expected under various scenarios of co-evolution and co-adaptation. But positive producer–consumer richness relationships may also arise from similar associations with past opportunities for diversification or contemporary environmental conditions, or from emerging properties of plant diversity such as vegetation complexity or productivity. Here we assess whether the producer–consumer richness relationship generalizes from plot to regional scale and provide a first global test of its strength for vascular plants and endothermic vertebrates. We find strong positive richness associations, but only limited congruence of the most diverse regions. The richness of both primary and higher-level consumers increases with plant richness at similar strength and rate. Environmental conditions emerge as much stronger predictors of consumer richness, and after accounting for environmental differences little variation is explained by plant diversity. We conclude that biotic interactions and strong local associations between plants and consumers only relatively weakly scale up to broad geographical scales and to functionally diverse taxa, for which environmental constraints on richness dominate.

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Small to large-scale patterns of ground-dwelling spider (Araneae) diversity across northern Canada

FACETS ◽

10.1139/facets-2018-0007 ◽

2018 ◽

Vol 3 (1) ◽

pp. 880-895 ◽

Cited By ~ 4

Author(s):

Sarah Loboda ◽

Christopher M. Buddle

Keyword(s):

Large Scale ◽

Sampling Design ◽

Spatial Scales ◽

Regional Scale ◽

Biotic Interactions ◽

Longitudinal Patterns ◽

Northern Canada ◽

Multiple Spatial Scales ◽

Spatial Influence ◽

Total Species

We examined how Arctic spider (Araneae) biodiversity is distributed at multiple spatial scales in northern Canada using a standardized hierarchical sampling design. We investigated which drivers, environmental or spatial, influence the patterns observed. Spatial patterns of Arctic spider species richness and composition were assessed in 12 sites located in arctic, subarctic, and north boreal ecoclimatic regions, spanning 30 degrees of latitude and 80 degrees of longitude. Variation in diversity was partitioned in relation to multiple environmental and spatial drivers of diversity patterns. Over 23 000 adult spiders, representing 306 species in 14 families, were collected in northern Canada, with 107 species (35% of the total species collected) representing new territorial or provincial records. Spider diversity was structured at the regional scale across ecoclimatic regions but was not structured with latitude. Longitudinal patterns of spider diversity across Canada may be explained by post-glacial dispersal. At local scales, diversity was non-randomly distributed and possibly limited by biotic interactions. We recommend the use of ecoclimatic regions as a framework for conservation of biodiversity in northern Canada and spiders as useful bioindicators that can help us understand the effects of climate change across ecoclimatic regions of northern Canada.

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Genomic and phenotypic divergence unveil microgeographic adaptation in the Amazonian hyperdominant tree Eperua falcata Aubl. (Fabaceae)

10.1101/312843 ◽

2018 ◽

Cited By ~ 2

Author(s):

Louise Brousseau ◽

Paul V. A. Fine ◽

Erwin Dreyer ◽

Giovanni G. Vendramin ◽

Ivan Scotti

Keyword(s):

De Novo ◽

Spatial Scales ◽

Regional Scale ◽

Biotic Interactions ◽

Plant Responses ◽

High Coverage ◽

Protein Coding ◽

Ecological Diversification ◽

A Genome ◽

Landscape Scales

AbstractPlant populations can undergo very localized adaptation, allowing widely distributed populations to adapt to divergent habitats in spite of recurrent gene flow. Neotropical trees - whose large and undisturbed populations often span a variety of environmental conditions and local habitats - are particularly good models to study this process. Here, we carried out a genome scan for selection through whole-genome sequencing of pools of populations, sampled according to a replicated sampling design, to evaluate microgeographic adaptation in the hyperdominant Amazonian tree Eperua falcata Aubl. (Fabaceae). A high-coverage genomic resource of ∼250 Mb was assembled de novo and annotated, leading to 32,789 predicted genes. 97,062 bi-allelic SNPs were detected over 25,803 contigs, and a custom Bayesian model was implemented to uncover candidate genomic targets of divergent selection. A set of 290 divergence outlier SNPs was detected at the regional scale (between study sites), while 185 SNPs located in the vicinity of 106 protein-coding genes were detected as replicated outliers between microhabitats within regions. Outlier genomic regions are involved in a variety of physiological processes, including plant responses to stress (e.g., oxidative stress, hypoxia and metal toxicity) and biotic interactions. Together with evidence suggesting microgeographic divergence in functional traits, the discovery of genomic targets of microgeographic adaptation in the Neotropics is consistent with the hypothesis that local adaptation is a key driver of ecological diversification, operating across multiple spatial scales, from large- (i.e. regional) to microgeographic- (i.e. landscape) scales.

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Factors Affecting the Rate of Fuel Consumption in Aircrafts

Sustainability ◽

10.3390/su13148066 ◽

2021 ◽

Vol 13 (14) ◽

pp. 8066

Author(s):

Thowayeb H. Hassan ◽

Abu Elnasr E. Sobaih ◽

Amany E. Salem

Keyword(s):

Fuel Consumption ◽

Positive Association ◽

Pollutant Emissions ◽

Aviation Industry ◽

Factors Affecting ◽

Fuel Flow ◽

Homogeneity Of Variance ◽

Strong Positive Association ◽

Ground Distance ◽

The Cost

The cost of fuel and its availability are among the most major concerns for aircrafts and the aviation industry overall. Environmental difficulties with chemical pollutant emissions emitted by aviation machines are also connected to fuel consumption. As a result, it is crucial to examine factors that affect the overall fuel usage and consumption in the airport-based aviation industry. Several variables were investigated related to the total fuel consumed, such as dry operating weight (DOW) (KG), zero-fuel weight (ZFW), take-off weight (TOW), air distance (AIR DIST) (KM), and ground distance (GDN DIST). Analysis of the correlation between total fuel consumed as well as the extra fuel and selected variables was conducted. The results showed that the most positively associated factors with the total used fuel were the air distance (r2 = 0.86, p < 0.01), ground distance (r2 = 0.78, p < 0.01), TOW (r2 = 0.68, p < 0.01), and flight time (r2 = 0.68, p < 0.01). There was also a strong positive association between the average fuel flow (FF) and actual TOW (r2 = 0.74, p < 0.01) as well as ZFW (r2 = 0.61, p < 0.01). The generalized linear model (GLM) was utilized to assess the predictions of total energy usage after evaluating important outliers, stability of the homogeneity of variance, and the normalization of the parameter estimation. The results of multiple linear regression revealed that the most significant predictors of the total consumed fuel were the actual ZFW (p < 0.01), actual TOW (p < 0.01), and actual average FF (p < 0.05). The results interestingly confirmed that wind speed has some consequences and effects on arrival fuel usage. The result reflects that thermal and hydrodynamic economies impact on the flying fuel economy. The research has various implications for both scholars and practitioners of aviation industry.

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Setting the Flow Accumulation Threshold Based on Environmental and Morphologic Features to Extract River Networks from Digital Elevation Models

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10030186 ◽

2021 ◽

Vol 10 (3) ◽

pp. 186

Author(s):

HuiHui Zhang ◽

Hugo A. Loáiciga ◽

LuWei Feng ◽

Jing He ◽

QingYun Du

Keyword(s):

Spatial Scales ◽

Digital Elevation Models ◽

Regional Scale ◽

Drainage Density ◽

River Network ◽

Landscape Patterns ◽

Estimation Methods ◽

River Networks ◽

Flow Accumulation ◽

Digital Elevation

Determining the flow accumulation threshold (FAT) is a key task in the extraction of river networks from digital elevation models (DEMs). Several methods have been developed to extract river networks from Digital Elevation Models. However, few studies have considered the geomorphologic complexity in the FAT estimation and river network extraction. Recent studies estimated influencing factors’ impacts on the river length or drainage density without considering anthropogenic impacts and landscape patterns. This study contributes two FAT estimation methods. The first method explores the statistical association between FAT and 47 tentative explanatory factors. Specifically, multi-source data, including meteorologic, vegetation, anthropogenic, landscape, lithology, and topologic characteristics are incorporated into a drainage density-FAT model in basins with complex topographic and environmental characteristics. Non-negative matrix factorization (NMF) was employed to evaluate the factors’ predictive performance. The second method exploits fractal geometry theory to estimate the FAT at the regional scale, that is, in basins whose large areal extent precludes the use of basin-wide representative regression predictors. This paper’s methodology is applied to data acquired for Hubei and Qinghai Provinces, China, from 2001 through 2018 and systematically tested with visual and statistical criteria. Our results reveal key local features useful for river network extraction within the context of complex geomorphologic characteristics at relatively small spatial scales and establish the importance of properly choosing explanatory geomorphologic characteristics in river network extraction. The multifractal method exhibits more accurate extracting results than the box-counting method at the regional scale.

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Microdiversity and phylogeographic diversification of bacterioplankton in pelagic freshwater systems revealed through long-read amplicon sequencing

Microbiome ◽

10.1186/s40168-020-00974-y ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Yusuke Okazaki ◽

Shohei Fujinaga ◽

Michaela M. Salcher ◽

Cristiana Callieri ◽

Atsushi Tanaka ◽

...

Keyword(s):

16S Rrna ◽

Regional Scale ◽

Scale Up ◽

Amplicon Sequencing ◽

Freshwater Ecosystems ◽

16S Rrna Genes ◽

Rrna Genes ◽

Rrna Gene ◽

Metagenomic Sequencing ◽

Long Read

Abstract Background Freshwater ecosystems are inhabited by members of cosmopolitan bacterioplankton lineages despite the disconnected nature of these habitats. The lineages are delineated based on > 97% 16S rRNA gene sequence similarity, but their intra-lineage microdiversity and phylogeography, which are key to understanding the eco-evolutional processes behind their ubiquity, remain unresolved. Here, we applied long-read amplicon sequencing targeting nearly full-length 16S rRNA genes and the adjacent ribosomal internal transcribed spacer sequences to reveal the intra-lineage diversities of pelagic bacterioplankton assemblages in 11 deep freshwater lakes in Japan and Europe. Results Our single nucleotide-resolved analysis, which was validated using shotgun metagenomic sequencing, uncovered 7–101 amplicon sequence variants for each of the 11 predominant bacterial lineages and demonstrated sympatric, allopatric, and temporal microdiversities that could not be resolved through conventional approaches. Clusters of samples with similar intra-lineage population compositions were identified, which consistently supported genetic isolation between Japan and Europe. At a regional scale (up to hundreds of kilometers), dispersal between lakes was unlikely to be a limiting factor, and environmental factors or genetic drift were potential determinants of population composition. The extent of microdiversification varied among lineages, suggesting that highly diversified lineages (e.g., Iluma-A2 and acI-A1) achieve their ubiquity by containing a consortium of genotypes specific to each habitat, while less diversified lineages (e.g., CL500-11) may be ubiquitous due to a small number of widespread genotypes. The lowest extent of intra-lineage diversification was observed among the dominant hypolimnion-specific lineage (CL500-11), suggesting that their dispersal among lakes is not limited despite the hypolimnion being a more isolated habitat than the epilimnion. Conclusions Our novel approach complemented the limited resolution of short-read amplicon sequencing and limited sensitivity of the metagenome assembly-based approach, and highlighted the complex ecological processes underlying the ubiquity of freshwater bacterioplankton lineages. To fully exploit the performance of the method, its relatively low read throughput is the major bottleneck to be overcome in the future.

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Protected Areas: offering security to whom, when and where?

Environmental Conservation ◽

10.1017/s0376892915000375 ◽

2016 ◽

Vol 43 (2) ◽

pp. 172-180 ◽

Cited By ~ 7

Author(s):

ALICE B. KELLY ◽

A. CLARE GUPTA

Keyword(s):

Protected Areas ◽

Environmental Conditions ◽

Protected Area ◽

Spatial Scales ◽

Local Population ◽

Well Being ◽

Economic Context ◽

Term Management ◽

Over Time

SUMMARYThis study considers the issue of security in the context of protected areas in Cameroon and Botswana. Though the literature on issues of security and well-being in relation to protected areas is extensive, there has been less discussion of how and in what ways these impacts and relationships can change over time, vary with space and differ across spatial scales. Looking at two very different historical trajectories, this study considers the heterogeneity of the security landscapes created by Waza and Chobe protected areas over time and space. This study finds that conservation measures that various subsets of the local population once considered to be ‘bad’ (e.g. violent, exclusionary protected area creation) may be construed as ‘good’ at different historical moments and geographical areas. Similarly, complacency or resignation to the presence of a park can be reversed by changing environmental conditions. Changes in the ways security (material and otherwise) has fluctuated within these two protected areas has implications for the long-term management and funding strategies of newly created and already existing protected areas today. This study suggests that parks must be adaptively managed not only for changing ecological conditions, but also for shifts in a protected area's social, political and economic context.

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A reinterpretation of Scottish ‘hummocky moraine’ and its significance for the deglaciation of the Scottish Highlands during the Younger Dryas or Loch Lomond Stadial

Geological Magazine ◽

10.1017/s0016756800019993 ◽

1993 ◽

Vol 130 (3) ◽

pp. 301-318 ◽

Cited By ~ 85

Author(s):

Matthew R. Bennett ◽

Geoffrey S. Boulton

Keyword(s):

Environmental Conditions ◽

Field Survey ◽

Spatial Scales ◽

Younger Dryas ◽

North West ◽

Scottish Highlands ◽

Ice Cap ◽

The North ◽

Loch Lomond

AbstractThe aim of this paper is to demonstrate that much of the ‘hummocky moraine’ present within the northern part of the LochLomond Readvance ice cap formerly situated in the North West Scottish Highlands may be interpreted as suites of ice-front moraines deposited during active decay. These landforms can be used to reconstruct ice cap decay, whichleads to important insights into the shrinking form of the ice cap and associated environmental conditions. Evidence has been collected from 10803 airphotographs and from detailed field survey. It is presented at three spatial scales.

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Hypertension, Cerebrovascular Disease and Stomach Cancer: Is the Salt Hypothesis True?

Clinical Science ◽

10.1042/cs061369s ◽

1981 ◽

Vol 61 (s7) ◽

pp. 369s-371s ◽

Cited By ~ 1

Author(s):

Paul K. Whelton ◽

Peter Goldblatt

Keyword(s):

Stomach Cancer ◽

Death Certificate ◽

Positive Association ◽

Special Relationship ◽

Death Rates ◽

Disease Associations ◽

Strong Positive Association ◽

Diagnostic Concordance ◽

The Relationship ◽

Unique Relationship

1. Analysis of age-adjusted death rates from 21 countries over a 20-year period identified the presence of a strong positive association between recorded mortality from stroke, hypertension and stomach cancer. However, the slopes of regression lines for secular trends analyses varied considerably from country to country, suggesting an inconsistency in the pattern of the relationship. 2. A death certificate study of diagnostic concordance correctly identified previously known disease associations but failed to recognise any special relationship between stroke and stomach cancer or hypertension and stomach cancer. 3. Our results fail to confirm the presence of a unique relationship between stroke and stomach cancer. On the basis of these observations, the hypothesis that exposure to salt increases an individual's risk of developing both stroke and stomach cancer seems unlikely.

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