Species pool size and realized species richness affect productivity differently: A modeling study

There is an opinion that the pressure of competition in the plant communities of stable and productive habitats leads to the decrease in evenness of structure of species abundance and species richness up to the monopolization of plots by the most successful competitor (Huston, 1979; Bengtsson et al., 1994). Hence, between the species richness of phytocoenoses and relative density of individuals of dominant species (RDD), negative dependence should be observed. However, according to another view, the number of species and structure of their abundance are determined by the different processes. The number of species is determined by the species pool size and the rate of species immigration, while the abundance structure — by the competition (Stirling, Wilsey, 2001; Ma, 2005; Wilsey, Stirling, 2007). In particular, in some communities a decrease of RDD leads to an increase in abundance of subdominant species and to oligodominant structure. These changes in relative abundance could occur without changes in species richness. Therefore these variables could be weakly related (Ma, 2005; Wilsey, Stirling, 2007; Munson, Lauenroth, 2009). However, it is unclear how widely these scenarios are realized in the plant cover. The aim of our study was to examine the relationship between RDD, the dominance structure as a whole (mono- or oligodominant), the species richness and the size of the species pool in the forest stands of the Western Caucasus.

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Probing the troublesome peaked relationship between avian species richness and natural land cover

10.21203/rs.3.rs-675821/v1 ◽

2021 ◽

Author(s):

Rafael Xavier De Camargo ◽

David Currie

Keyword(s):

Species Richness ◽

Land Cover ◽

Landscape Heterogeneity ◽

New York State ◽

Pool Size ◽

Avian Species ◽

Temperature Gradients ◽

Species Pool ◽

Natural Land ◽

The Relationship

Abstract Context : Biodiversity models postulate that the relationship between richness and the proportion of natural land cover (pNLC i.e., not dominated by human uses) is: 1) monotonic positive, 2) reasonably strong , 3) consistent in different geographic areas . Earlier work examining 100-km 2 human-dominated landcover in Ontario, Canada, observed that surveyed avian species richness is a peaked function of pNLC. Objective : We tested whether the same relationship between avian species richness and pNLC is also observed in an independent geographic area that has similar biomes. We also tested whether the peaked relations might be caused by temperature gradients, gradients in the size of species pools, grain size in the analyses, and landscape heterogeneity. Methods : Using breeding bird atlases of Ontario (Canada) and New York State (USA), we estimated species richness in landscapes varying from 25 to 900 km 2 . We related richness to the pNLC in each landscape and examined the same relationships after controlling for temperature, habitat heterogeneity, and species pool size. Results : Landscape-level species richness is a peaked, and not very strong function of pNLC. The relationship is not an artefact of temperature gradients, species pool size, or land cover heterogeneity. Conclusions : The proposition that increased amounts of natural land cover promotes species richness is clearly true at the limit, in landscapes with relatively little (<30%) natural cover. In landscapes with higher amounts of natural cover, a certain amount of human-modified land covers can provide habitat for species that prefer open habitats.

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Species pool size and invasibility of island communities: a null model of sampling effects

Ecology Letters ◽

10.1111/j.1461-0248.2005.00790.x ◽

2005 ◽

Vol 8 (9) ◽

pp. 909-917 ◽

Cited By ~ 33

Author(s):

Tomas Herben

Keyword(s):

Null Model ◽

Pool Size ◽

Species Pool ◽

Island Communities

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Importance of Soil Organic Matter and the Species Pool for Local Species Richness in Montane Ecosystems

Sustainability ◽

10.3390/su131910634 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10634

Author(s):

Xiang Li ◽

Wenhao Hu ◽

Zhenrong Yu

Keyword(s):

Species Richness ◽

Plant Species ◽

Plant Species Richness ◽

Species Pool ◽

Multi Scale ◽

Local Species Richness ◽

Local Plant ◽

Regional Species Pool ◽

Urban Rural ◽

Local Species

Understanding the response of plant species richness to environmental filters is critical for conservation management as there is an increasing emphasis on plant restoration in urban/rural planning. However, empirical studies on the effects that the regional species pool has on plant species richness often overlook small spatial scales, therefore requiring more comprehensive approaches. As mountains can act as barriers to plant dispersal, the impact on the species pool, particularly, should be a priority. This study aimed to investigate how the regional species pool affects the local plant species richness in a multivariate context. We sampled vascular plant communities along three transects located in three valleys across the Chongli District, China, where four common habitat types were selected for sampling: grassland, shrubbery, pure forest, and mixed forest. We compared the differences in the multi-scale species richness and species composition between habitats and regions and used piecewise structural equation modeling to analyze the relative importance of the regional species pool, habitat species pool, soil resource availability, and exposure for local plant richness. The β-diversity had the highest contribution to the total species richness between valleys and habitats. The species composition between regions and habitats showed a significant difference and the local species richness was most strongly affected by the soil characteristics, but effects from the regional species pool still played an important role. Conservation efforts and urban/rural planning should use a multi-level and multi-scale approach based on a detailed structural investigation.

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