Decomposition disentangled: a test of the multiple mechanisms by which nitrogen enrichment alters litter decomposition

Pichon, Noémie A.; Cappelli, Seraina L.; Soliveres, Santiago; Hölzel, Norbert; Klaus, Valentin H.; Kleinebecker, Till; Allan, Eric

doi:10.1101/671545

Cited by 13 publications

(22 citation statements)

References 62 publications

(11 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results were in agreement with those of previous studies (McLaren and Turkington 2010;Zhao et al 2017). A large number of studies have found that there is a close correlation between the initial N content and N-related indicators, especially C: N and lignin: N, which are considered as evident indicators for predicting the litter decomposition rate (Mooshammer et al 2012;Pichon et al 2020). This may be the reason that the leaf litter of broad-leaved species had a slower decomposition rate than the fine roots, while the opposite result was found for coniferous species (Fig.…”

Section: Effect Of Litter Type and Species On The Bacterial Diversitysupporting

confidence: 92%

Leaf and Root Litter Species Identity Influences Bacterial Community Composition in Short-Term Litter Decomposition

et al. 2020

Preprint

View full text Add to dashboard Cite

Background: Microorganisms play a crucial role in litter decomposition in terrestrial ecosystems. However, it remains unclear, which effects of leaf litter and root species on bacterial community composition and diversity after one year's decomposition. Methods: The leaf and fine roots litters of Robinia pseudoacacia , Quercus acutissima , Pinus tabulaeformis and Pinus densiflora , which are the dominant afforestation species in Mount Tai, were analysed using the Nylon litterbag method and Illumina Miseq high-throughput sequencing for the amplification of bacterial 16S rRNA V4-V5. We measured the remaining litter mass and the bacterial community composition and assessed the effects of leaf and root litter species on the bacterial community after one-year decomposition periods.Results: (1) The remaining masses of leaf and fine roots litters of the four plant species were significantly influenced by organ type and species. The remaining mass of fine root litter was smaller than that of leaf litter for broad-leaved species, and the opposite result was found for coniferous species. (2) The observed species Chao1 and phylogenetic diversity values were significantly lower for leaf litters than for fine root litter. The community richness index was positively correlated with the C content, C:N and lignin content and negatively correlated with N:P, N content and P content. The bacterial community structure differed significantly among leaf and root litter decomposition for the four species ( p <0.05). The bacterial community structure in leaf litter was most highly correlated with the initial N content and N:P. The bacterial community structure in fine roots was most highly correlated with the lignin content. (3) The bacterial phyla Bacteroidetes , Acidobacteria and Gemmatimonadetes were significantly affected by litter and species type, and the relative abundances of Firmicutes and Chloroflexi were only affected by litter type. The relative abundances of Acidobacteria , Firmicutes and Chloroflexi in fine root litter were higher than those in leaf litter, while the opposite result was found for Bacteroidetes . The bacterial genera Burkholderia-Paraburkholderia , Sphingomonas and Mucilaginibacter were affected by litter type ( p <0.05). The relative abundance of Burkholderia-Paraburkholderia in fine root litter was higher than that in leaf litter, while the opposite result was found for Bradyrhizobium , Sphingomonas and Mucilaginibacter . Pearson correlation analysis showed that the average relative abundance of the dominant phyla and genera was affected by the initial litter properties, especially for Bacteroides , Acidobacteria , Burkholderia , and Sphingomonas . Conclusions: Litter type, interaction between litter type and species were important than species in shaping the bacterial diversity and community composition in decomposing litter. And this were affected by initial chemical properties of the litter.

show abstract

Section: Effect Of Litter Type and Species On The Bacterial Diversitysupporting

confidence: 92%

Leaf and Root Litter Species Identity Influences Bacterial Community Composition in Short-Term Litter Decomposition

et al. 2020

Preprint

View full text Add to dashboard Cite

show abstract

“…Plots were mown once in the middle of June and once in August (see Supplementary Methods and Pichon et al . 2020).…”

Section: Methodsmentioning

confidence: 99%

Sick plants in grassland communities: a growth‐defense trade‐off is the main driver of fungal pathogen abundance

et al. 2020

Self Cite

View full text Add to dashboard Cite

Aboveground fungal pathogens can substantially reduce biomass production in grasslands. However, we lack a mechanistic understanding of the drivers of fungal pathogen infection and impact. Using a grassland global change and biodiversity experiment we show that the trade-off between plant growth and defense is the main determinant of infection incidence. In contrast, nitrogen addition only indirectly increased incidence via shifting plant communities towards faster growing species. Plant diversity did not decrease incidence, likely because spillover of generalist pathogens or dominance of susceptible plants counteracted negative diversity effects. A fungicide treatment increased plant biomass production and high levels of infection incidence were associated with reduced biomass. However, pathogen impact was context dependent and infection incidence reduced biomass more strongly in diverse communities. Our results show that a growth-defense trade-off is the key driver of pathogen incidence, but pathogen impact is determined by several mechanisms and may depend on pathogen community composition.

show abstract

“…The mean volumetric water content of 5.95% indicated rather dry conditions when we collected the samples for the present study (mean from June to August 2017). Further information about the design of PaNDiv and field characteristics can be found in Pichon, Cappelli, Soliveres, Hölzel, et al (2020).…”

Section: Methodsmentioning

confidence: 99%

“…The use of functional traits has revolutionised community ecology and allowed a more mechanistic and predictive understanding of these compositional shifts and therefore of how plant communities respond to global change (Allan et al, 2015; Lavorel & Grigulis, 2012; McGill et al, 2006; de Vries et al, 2012). At the same time functional traits have been shown in many studies to be good predictors of ecosystem functioning (Allan et al, 2015; Cappelli et al, 2020; Díaz et al, 2007; Lavorel & Grigulis, 2012; Pichon, Cappelli, Soliveres, Hölzel, et al, 2020; Ratcliffe et al, 2017; Roscher et al, 2013), although weaker effects have also been observed (van der Plas et al, 2020). Mean plant trait values therefore simultaneously respond to global changes and affect ecosystem functioning, and changes in functional trait composition may be a major mechanism explaining global change effects on functioning (Allan et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

Intraspecific trait changes have large impacts on community functional composition but do not affect ecosystem function

2022

Self Cite

View full text Add to dashboard Cite

Plant functional traits can provide a mechanistic understanding of community responses to global change and of community effects on ecosystem functions. Nitrogen enrichment typically shifts trait composition by promoting the dominance of acquisitive plants (high specific leaf area [SLA] and low leaf dry matter content [LDMC]), translating into high biomass production. Changes in mean trait values can be due to shifts in species identity, relative abundances and/or intraspecific trait values. However, we do not know the relative importance of these shifts in determining trait responses to environmental changes, or trait effects on ecosystem functioning, such as biomass production. We quantified the relative importance of species composition, abundance and intraspecific shifts in driving variation in SLA and LDMC, and how these shifts affected above‐ and below‐ground biomass. We measured traits in a grassland experiment manipulating nitrogen fertilisation, plant species richness, foliar fungal pathogen removal and sown functional composition (slow vs. fast species). We fitted structural equation models to test the importance of abundance and intraspecific shifts in determining (a) responses of functional composition to treatments and (b) effects on above‐ and below‐ground biomass. We found that species intraspecific shifts were as important as abundance shifts in determining the overall change in functional composition (community weighted mean trait values), and even had large effects compared to substantial initial variation in sown trait composition. Intraspecific trait shifts resulted in convergence towards intermediate SLA in diverse communities; although convergence was reduced by nitrogen addition and enhanced by pathogen removal. In contrast, large intraspecific shifts in LDMC were not influenced by the treatments. However, despite large responses, intraspecific trait shifts had no effect on above‐ or below‐ground biomass. Only interspecific trait variation affected functioning: below‐ground biomass was reduced by SLA and increased by LDMC, while above‐ground biomass was increased by SLA. Synthesis. Our results add to a growing body of literature showing large intraspecific trait variation and emphasise the importance of using field collected data to determine community functional composition. However, they also show that intraspecific variation does not necessarily affect ecosystem functioning and therefore response–effect trait relationships may differ between versus within species.

show abstract

Decomposition disentangled: a test of the multiple mechanisms by which nitrogen enrichment alters litter decomposition

Cited by 13 publications

References 62 publications

Leaf and Root Litter Species Identity Influences Bacterial Community Composition in Short-Term Litter Decomposition

Leaf and Root Litter Species Identity Influences Bacterial Community Composition in Short-Term Litter Decomposition

Sick plants in grassland communities: a growth‐defense trade‐off is the main driver of fungal pathogen abundance

Intraspecific trait changes have large impacts on community functional composition but do not affect ecosystem function

Contact Info

Product

Resources

About