Reducing dispersal limitation via seed addition increases species richness but not above‐ground biomass

Abstract Background: Studies on the relationships between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem processes. There is no general pattern regarding the relationship found in various studies, and positive, unimodal, negative, and neutral relationships keep the issue controversial. In this study, taxonomic diversity vs functional diversity as drivers of above-ground biomass were compared, and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio hypoteses.Methods: Using data from 414 permanent sampling plots, covering 23% of temperate forests in the Sierra Madre Occiental (Mexico), we estimated the above-ground biomass (AGB) for trees ≥7.5 cm d.b.h. in managed and unmanaged stands. We evaluated AGB-diversity relationships (species richness, Shannon-Wiener and Simpson indices), AGB-weighted mean community values (CWM) of tree species functional traits (maximum height, leaf size, and wood density) and five measures of functional diversity (functional dispersion, functional richness, functional uniformity, functional diversity, and RaoQ index).Results: We reveal a consistent hump-shaped relationship between aboveground biomass and species richness in managen and unmanaged forest. CWM_Hmax was the most important predictor of AGB in both managed and unmanaged stands, which suggests that the mechanism that explains the above-ground biomass in these ecosystems is dominated by certain highly productive species in accordance of the mass-ratio hypothesis. There were no significant relationships between taxonomic diversity metrics (Shannon-Wiener and Simpson indices) or measures of functional diversity with AGB. The results support the mass-ratio hypothesis to explain the AGB variations.Conclusions: We concluded that diversity does not influence biomass production in the temperate mixed-species and uneven-aged forests of northern Mexico. These forests showed the classic hump-shaped productivity-species richness relationship, with biomass accumulation increasing at low to intermediate levels of species plant diversity and decreasing at high species richness. Functional diversity explains better forest productivity than classical diversity metrics.

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Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico

10.21203/rs.3.rs-42734/v3 ◽

2020 ◽

Author(s):

Benedicto Vargas-Larreta ◽

Jorge Omar Lopez Martinez ◽

Edgar J. González ◽

Jose Javier Corral-Rivas ◽

Francisco Javier Hernández

Keyword(s):

Species Richness ◽

Functional Diversity ◽

Taxonomic Diversity ◽

Maximum Height ◽

Above Ground Biomass ◽

Northern Mexico ◽

Ground Biomass ◽

Sierra Madre ◽

Community Weighted Mean ◽

The Relationship

Abstract Background: Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem processes. Several patterns on this relationship have been found, including positive, unimodal, negative, and neutral trends, keeping the issue controversial. In this study, taxonomic diversity and functional diversity as drivers of above-ground biomass (AGB) were comparated, and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio hypotheses.Methods: Using data from 414 permanent sample plots, covering 23% of temperate forest in the Sierra Madre Oriental (México). We estimated the above-gound biomass (AGB), taxonomic and functional diversity indices, as well as community weighted mean values (CWM) for three functional trais (maximum height, leaf size and wood density) for trees ≥7.5 cm d.b.h., in managed and unmanaged stands. To compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction analysis. Furthermore, we evaluated the relationship between AGB and taxonomic and functional diversity metrics, as well as CWM traits throught spatial autoregressive models.Results: We found a hump-shaped relationship between AGB and species richness in managed and unmanaged forests. CMW of maximum height was the most important predictor of AGB in both stands, which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species, supporting the mass-ratio hypothesis. Above-ground biomass was significantly correlated with three of the five functional diversity metrics, CWM maximum height and species richness. Our results show the importance of take into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGB-diversity relationship.Conclusion: Species richness, maximum height, functional richness, functional dispersion and RaoQ indices relate with above-ground biomass production in temperate mixed-species and uneven-aged forests of northern Mexico. These forests show a hump-shaped AGB-species richness relationship. Functional diversity explains better AGB production than classical taxonomic diversity. Community weighted mean traits provide key information to explain stand biomass in these forests, where maximum tree height seems to be a more suitable trait for understanding the biomass accumulation process in these ecosystems. Although the impact of forest management on biodiversity is still debated, it has not changed the AGB-diversity relationships in the forests of the Sierra Madre Occidental, Mexico.

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Species Richness and Biomass Relationship in Burned Sites of Imperata-Saccharum Grassland in Suklaphanta Wildlife Reserve, Nepal

Ecoprint An International Journal of Ecology ◽

10.3126/eco.v15i0.1938 ◽

2009 ◽

Vol 15 ◽

pp. 23-27

Author(s):

Pitamber Pant ◽

Hari Datt Lekhak

Keyword(s):

Species Richness ◽

Generalized Linear Model ◽

Plant Community Composition ◽

Above Ground Biomass ◽

Ground Biomass ◽

Burned Site ◽

June July ◽

Wildlife Reserve ◽

The Relationship ◽

Shaped Pattern

Present study was conducted in the Suklaphanta Wildlife Reserve, Kanchanpur district, far western Nepal during June-July, 2005. A total of 150 quadrats (1m x 1m) were sampled in three differentially treated sites (unburned, early burned and late burned). Plant community composition and above ground biomass at different sites were quantified. The relationship between species richness and biomass was detected in the Imperata-Saccharum grassland. Altogether 100 plant species were recorded in the grassland. The highest number of species (62) was recorded in early burned site, whereas lowest (54) species were recorded from unburned site. Among all species recorded, 23 were common to all sites. The highest species richness (13 species/m²) was recorded in the early burned plot. The above ground biomass was highest (583.93 g/m²) in unburned plot. Mean above ground biomass of all the three sites of the grassland was 249.72 g/m². These results indicate that the burning has significant impact on both species richness and biomass. Maximum species richness was found in the biomass interval between ca. 100-300 g/m² when all the sites were combined. A hump shaped pattern was observed in the grassland when all the data were combined. Key words: Species richness, biomass, generalized linear model, fire. doi: 10.3126/eco.v15i0.1938 ECOPRINT 15: 23-27, 2008

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Grain size affects the relationship between species richness and above-ground biomass in semi-arid rangelands

Plant Ecology & Diversity ◽

10.1080/17550874.2018.1534144 ◽

2018 ◽

Vol 11 (4) ◽

pp. 489-499 ◽

Cited By ~ 2

Author(s):

Anvar Sanaei ◽

Íñigo Granzow-de la Cerda ◽

Luis Cayuela

Keyword(s):

Grain Size ◽

Species Richness ◽

Above Ground Biomass ◽

Ground Biomass ◽

Arid Rangelands ◽

The Relationship ◽

Semi Arid

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