Significant competitive dominance in mid-latitude European plant communities

Understanding the main determinants of species coexistence across space and time is a central question in ecology. However, ecologists still know little about the scales and conditions at which biotic interactions matter and their interplay with the environment to structure species assemblages. Here we develop ecological theory to analyze plant distribution and trait data across Europe and find that plant height clustering is related to evapotranspiration and gross primary productivity. Our analysis suggests competitive dominance as a plausible mechanism underlying community assembly patterns over these continental scales. In particular, we find a clear signal of plant-to-plant competition in mid-latitude ecoregions, where conditions for growth (reflected in actual evapotranspiration rates and gross primary productivities) are optimal. Under severe conditions, either climate is too harsh and overrides the effect of competition or other interactions play a relevant role. Our approach bridges the gap between modern coexistence theory and large-scale species distribution data analysis.

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A signal of competitive dominance in mid-latitude herbaceous plant communities

Royal Society Open Science ◽

10.1098/rsos.201361 ◽

2021 ◽

Vol 8 (9) ◽

pp. 201361

Author(s):

José A. Capitán ◽

Sara Cuenda ◽

Alejandro Ordóñez ◽

David Alonso

Keyword(s):

Primary Productivity ◽

Large Scale ◽

Species Coexistence ◽

Biotic Interactions ◽

Plant Distribution ◽

Distribution Data ◽

Herbaceous Plant ◽

Central Question ◽

Main Determinants ◽

Theoretical Developments

Understanding the main determinants of species coexistence across space and time is a central question in ecology. However, ecologists still know little about the scales and conditions at which biotic interactions matter and how these interact with the environment to structure species assemblages. Here we use recent theoretical developments to analyse plant distribution and trait data across Europe and find that plant height clustering is related to both evapotranspiration (ET) and gross primary productivity. This clustering is a signal of interspecies competition between plants, which is most evident in mid-latitude ecoregions, where conditions for growth (reflected in actual ET rates and gross primary productivities) are optimal. Away from this optimum, climate severity probably overrides the effect of competition, or other interactions become increasingly important. Our approach bridges the gap between species-rich competition theories and large-scale species distribution data analysis.

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Modeling Spatiotemporal Population Changes by Integrating DMSP-OLS and NPP-VIIRS Nighttime Light Data in Chongqing, China

Remote Sensing ◽

10.3390/rs13020284 ◽

2021 ◽

Vol 13 (2) ◽

pp. 284

Author(s):

Dan Lu ◽

Yahui Wang ◽

Qingyuan Yang ◽

Kangchuan Su ◽

Haozhe Zhang ◽

...

Keyword(s):

Spatial Distribution ◽

Relative Error ◽

Urban Areas ◽

Large Scale ◽

Population Distribution ◽

Spatial Optimization ◽

Distribution Data ◽

Mountainous Areas ◽

Mean Relative Error ◽

Nighttime Light

The sustained growth of non-farm wages has led to large-scale migration of rural population to cities in China, especially in mountainous areas. It is of great significance to study the spatial and temporal pattern of population migration mentioned above for guiding population spatial optimization and the effective supply of public services in the mountainous areas. Here, we determined the spatiotemporal evolution of population in the Chongqing municipality of China from 2000–2018 by employing multi-period spatial distribution data, including nighttime light (NTL) data from the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) and the Suomi National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP-VIIRS). There was a power function relationship between the two datasets at the pixel scale, with a mean relative error of NTL integration of 8.19%, 4.78% less than achieved by a previous study at the provincial scale. The spatial simulations of population distribution achieved a mean relative error of 26.98%, improved the simulation accuracy for mountainous population by nearly 20% and confirmed the feasibility of this method in Chongqing. During the study period, the spatial distribution of Chongqing’s population has increased in the west and decreased in the east, while also increased in low-altitude areas and decreased in medium-high altitude areas. Population agglomeration was common in all of districts and counties and the population density of central urban areas and its surrounding areas significantly increased, while that of non-urban areas such as northeast Chongqing significantly decreased.

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Demographic effects of interacting species: exploring stable coexistence under increased climatic variability in a semiarid shrub community

Scientific Reports ◽

10.1038/s41598-021-82571-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ana I. García-Cervigón ◽

Pedro F. Quintana-Ascencio ◽

Adrián Escudero ◽

Merari E. Ferrer-Cervantes ◽

Ana M. Sánchez ◽

...

Keyword(s):

Population Dynamics ◽

Species Coexistence ◽

Climatic Factors ◽

Demographic Data ◽

Climatic Variability ◽

Biotic Interactions ◽

Vital Rates ◽

Climatic Fluctuations ◽

Demographic Models ◽

Shrub Community

AbstractPopulation persistence is strongly determined by climatic variability. Changes in the patterns of climatic events linked to global warming may alter population dynamics, but their effects may be strongly modulated by biotic interactions. Plant populations interact with each other in such a way that responses to climate of a single population may impact the dynamics of the whole community. In this study, we assess how climate variability affects persistence and coexistence of two dominant plant species in a semiarid shrub community on gypsum soils. We use 9 years of demographic data to parameterize demographic models and to simulate population dynamics under different climatic and ecological scenarios. We observe that populations of both coexisting species may respond to common climatic fluctuations both similarly and in idiosyncratic ways, depending on the yearly combination of climatic factors. Biotic interactions (both within and among species) modulate some of their vital rates, but their effects on population dynamics highly depend on climatic fluctuations. Our results indicate that increased levels of climatic variability may alter interspecific relationships. These alterations might potentially affect species coexistence, disrupting competitive hierarchies and ultimately leading to abrupt changes in community composition.

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Modelling Tree Growth in Monospecific Forests from Forest Inventory Data

Forests ◽

10.3390/f12060753 ◽

2021 ◽

Vol 12 (6) ◽

pp. 753

Author(s):

Guadalupe Sáez-Cano ◽

Marcos Marvá ◽

Paloma Ruiz-Benito ◽

Miguel A. Zavala

Keyword(s):

Tree Growth ◽

Large Scale ◽

Temporal Dynamics ◽

Carbon Sink ◽

Size Variation ◽

Biotic Interactions ◽

Richards Equation ◽

Tree Level ◽

Forest Inventories ◽

Large Scale Data

The prediction of tree growth is key to further understand the carbon sink role of forests and the short-term forest capacity on climate change mitigation. In this work, we used large-scale data available from three consecutive forest inventories in a Euro-Mediterranean region and the Bertalanffy–Chapman–Richards equation to model up to a decade’s tree size variation in monospecific forests in the growing stages. We showed that a tree-level fitting with ordinary differential equations can be used to forecast tree diameter growth across time and space as function of environmental characteristics and initial size. This modelling approximation was applied at different aggregation levels to monospecific regions with forest inventories to predict trends in aboveground tree biomass stocks. Furthermore, we showed that this model accurately forecasts tree growth temporal dynamics as a function of size and environmental conditions. Further research to provide longer term prediction forest stock dynamics in a wide variety of forests should model regeneration and mortality processes and biotic interactions.

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Ecological processes maintaining differential tree species distributions in an Australian subtropical rain forest: implications for models of species coexistence

Journal of Tropical Ecology ◽

10.1017/s0266467400001474 ◽

2000 ◽

Vol 16 (3) ◽

pp. 387-415 ◽

Cited By ~ 20

Author(s):

Igor Debski ◽

David F. R. P. Burslem ◽

David Lamb

Keyword(s):

Species Composition ◽

Tree Species ◽

Rain Forest ◽

Large Scale ◽

Species Coexistence ◽

Common Species ◽

Size Class ◽

Differential Mortality ◽

Mixed Composition ◽

Large Scale Disturbance

All stems ≥ 1 cm dbh were measured, tagged, mapped and identified on a 1-ha plot of rain forest at Gambubal State Forest, south-east Queensland, Australia. The spatial patterns and size class distributions of 11 common tree species on the plot were assessed to search for mechanisms determining their distribution and abundance. The forest was species-poor in comparison to many lowland tropical forests and the common species are therefore present at relatively high densities. Despite this, only limited evidence was found for the operation of density-dependent processes at Gambubal. Daphnandra micrantha saplings were clumped towards randomly spaced adults, indicating a shift of distribution over time caused by differential mortality of saplings in these adult associated clumps. Ordination of the species composition in 25-m × 25-m subplots revealed vegetation gradients at that scale, which corresponded to slope across the plot. Adult basal area was dominated by a few large individuals of Sloanea woollsii but the comparative size class distributions and replacement probabilities of the 11 common species suggest that the forest will undergo a transition to a more mixed composition if current conditions persist. The current cohort of large S. woollsii individuals probably established after a large-scale disturbance event and the forest has not attained an equilibrium species composition.

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Advances in species coexistence theory

Biodiversity Science ◽

10.17520/biods.2017034 ◽

2017 ◽

Vol 25 (4) ◽

pp. 345-354 ◽

Cited By ~ 1

Author(s):

Chengjin Chu ◽

◽

Youshi Wang ◽

Yu Liu ◽

Lin Jiang ◽

...

Keyword(s):

Species Coexistence ◽

Coexistence Theory

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An Efficient Partition-Based Approach to Identify and Scatter Multiple Relevant Spreaders in Complex Networks

Entropy ◽

10.3390/e23091216 ◽

2021 ◽

Vol 23 (9) ◽

pp. 1216

Author(s):

Jedidiah Yanez-Sierra ◽

Arturo Diaz-Perez ◽

Victor Sosa-Sosa

Keyword(s):

Complex Networks ◽

Information Diffusion ◽

Large Scale ◽

Centrality Measures ◽

Correct Identification ◽

Graph Analysis ◽

Relevant Role ◽

Two Phases ◽

Large Scale Networks ◽

Spreading Processes

One of the main problems in graph analysis is the correct identification of relevant nodes for spreading processes. Spreaders are crucial for accelerating/hindering information diffusion, increasing product exposure, controlling diseases, rumors, and more. Correct identification of spreaders in graph analysis is a relevant task to optimally use the network structure and ensure a more efficient flow of information. Additionally, network topology has proven to play a relevant role in the spreading processes. In this sense, more of the existing methods based on local, global, or hybrid centrality measures only select relevant nodes based on their ranking values, but they do not intentionally focus on their distribution on the graph. In this paper, we propose a simple yet effective method that takes advantage of the underlying graph topology to guarantee that the selected nodes are not only relevant but also well-scattered. Our proposal also suggests how to define the number of spreaders to select. The approach is composed of two phases: first, graph partitioning; and second, identification and distribution of relevant nodes. We have tested our approach by applying the SIR spreading model over nine real complex networks. The experimental results showed more influential and scattered values for the set of relevant nodes identified by our approach than several reference algorithms, including degree, closeness, Betweenness, VoteRank, HybridRank, and IKS. The results further showed an improvement in the propagation influence value when combining our distribution strategy with classical metrics, such as degree, outperforming computationally more complex strategies. Moreover, our proposal shows a good computational complexity and can be applied to large-scale networks.

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Genotype-Species Interactions in Neighbourhoods of Forest Tree Communities

Silvae Genetica ◽

10.1515/sg-2007-0016 ◽

2007 ◽

Vol 56 (1-6) ◽

pp. 101-110 ◽

Cited By ~ 5

Author(s):

Chr. Wehenkel ◽

F. Bergmann ◽

H.-R. Gregorius

Keyword(s):

Species Interactions ◽

Species Coexistence ◽

Biotic Interactions ◽

Forest Tree ◽

Target Species ◽

Species Identity ◽

Enzymatic Function ◽

Genotype Frequencies ◽

Tree Communities ◽

Large Survey

Abstract Studies on plant communities of various annual species suggest that there are particular biotic interactions among individuals from different species which could be the basis for long-term species coexistence. In the course of a large survey on species-genetic diversity relationships in several forest tree communities, it was found that statistically significant differences exist among isozyme genotype frequencies of conspecific tree groups, which differ only by species identity of their neighbours. Based on a specific measure, the association of the neighbouring species with the genotypes of the target species or that of the genotypes with the neighbouring species was quantified. Since only AAT and HEK of the five analysed enzyme systems differed in their genotype frequencies among several tree groups of the same target species, a potential involvement of their enzymatic function in the observed differences was discussed. The results of this study demonstrate a fine-scale genetic differentiation within single tree species of forest communities, which may be the result of biotic interactions between the genetic structure of a species and the species composition of its community. This observation also suggests the importance of intraspecific genetic variation for interspecific adaptation.

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Takhtajan's floristic regions and foliicolous lichen biogeography: a compatibility analysis

The Lichenologist ◽

10.1006/lich.2002.0430 ◽

2003 ◽

Vol 35 (1) ◽

pp. 33-53 ◽

Cited By ~ 28

Author(s):

Robert Lücking

Keyword(s):

Large Scale ◽

New Caledonia ◽

Vascular Plant ◽

Distribution Patterns ◽

Plant Distribution ◽

Sufficient Information ◽

East African ◽

Foliicolous Lichens ◽

North East ◽

Compatibility Analysis

AbstractTakhtajan's floristic regions of the world, based on vascular plant distribution, were used for a comparative analysis of foliicolous lichen biogeography. Of the 35 regions distinguished by that author, 23 feature foliicolous lichens. The South-East African, Fijian, Polynesian and Hawaiian regions lack sufficient information and were excluded from further analysis. Using multi-dimensional scaling and cluster and cladistic analyses, the remaining 19 regions were grouped into six lichenogeographical regions: (1) Neotropics, (2) African Paleotropics (including Madagascar, Réunion and Seychelles), (3) Eastern Paleotropics (including North-East Australia and New Caledonia), (4) Valdivian region (temperate rainforest in southern South America), (5) Tethyan region (subtropical areas of Macaronesia, Mediterranean, and Western Irano-Turanian) and (6) Neozealandic-Tasmanian region (temperate rainforests of New Zealand and Tasmania). Affinities between these six large scale regions, with 57–77% shared species, are still stronger than those between the 35 smaller scale regions denned by Takhtajan [(20−)40–60(−75)% shared species]. Based on presence/absence within each of the six regions, 22 potential distribution patterns were defined for foliicolous lichens. Many species are widely distributed; 21% are cosmopolitan or pantropical, while 19% are disjunct on at least two continents, and only 60% are restricted to one of the three major tropical areas (nearly 100% in vascular plants). Most of the latter are found in the Neotropics, while the African Paleotropics are poor in endemics. Most genera deviate significantly from overall distribution patterns; for example, Strigula and Calopadia have higher proportions of widely distributed species, while Porina displays a concentration of Eastern Paleotropical endemics. Species diversity and composition of the six regions indicate that the three extra-tropical foliicolous lichen biotas (Valdivian, Tethyan, Neozealandic-Tasmanian) are the result of partly separate evolutionary histories. On the other hand, there is a strong affinity between the Neotropics and the African Paleotropics, suggesting a shared Western Gondwanan element in the foliicolous lichen biotas of these two regions.

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Beyond direct neighbourhood effects: higher-order interactions improve modelling and predicting tree survival and growth

National Science Review ◽

10.1093/nsr/nwaa244 ◽

2020 ◽

Author(s):

Yuanzhi Li ◽

Margaret M Mayfield ◽

Bin Wang ◽

Junli Xiao ◽

Kamil Kral ◽

...

Keyword(s):

Species Diversity ◽

Temperate Forest ◽

Species Coexistence ◽

Biotic Interactions ◽

Higher Order ◽

Individual Level ◽

Pairwise Interactions ◽

Tree Survival ◽

Survival And Growth ◽

Tree Performance

Abstract It is known that biotic interactions are the key to species coexistence and maintenance of species diversity. Traditional studies focus overwhelmingly on pairwise interactions between organisms, ignoring complex higher-order interactions (HOIs). In this study, we present a novel method of calculating individual-level HOIs for trees, and use this method to test the importance of size- and distance-dependent individual-level HOIs to tree performance in a 25-ha temperate forest dynamic plot. We found that full HOIs-inclusive models improved our ability to model and predict the survival and growth of trees, providing empirical evidence that HOIs strongly influence tree performance in this temperate forest. Specifically, assessed HOIs mitigate the competitive direct effects of neighbours on survival and growth of focal trees. Our study lays a foundation for future investigations of the prevalence and relative importance of HOIs in global forests and their impact on species diversity.

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