Abiotic and biotic drivers underly short- and long-term soil respiration responses to experimental warming in a dryland ecosystem

Dacal, Marina; García‐Palacios, Pablo; Asensio, Sergio; Gozalo, Beatriz; Ochoa, Victoria; Maestre, Fernando T.

doi:10.1101/2020.01.13.903880

Cited by 2 publications

(1 citation statement)

References 74 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, our results indicate that these increases in soil respiration with warming are not only due to a higher lichen mortality, but also to a higher decomposition of their tissues. Interestingly, this positive effect of warming on soil respiration disappears 8-10 years after the setup of the experiment (Dacal and others 2020), when the mortality of biocrust-forming lichens was mostly halted compared to the initial years of the experiment (Ladrón de Guevara and others 2018).…”

Section: Discussionmentioning

confidence: 99%

Litter decomposition rates of biocrust-forming lichens are similar to that of vascular plants and are affected by warming in a semiarid grassland

Berdugo

Mendoza-Aguilar

Rey

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

25Despite the high relevance of communities dominated by lichens, mosses and cyanobacteria 26 living on the soil surface (biocrusts) for ecosystem functioning in drylands worldwide, no study 27 to date has investigated the decomposition of biocrust-forming lichen litter in situ. Thus, we do 28 not know whether the drivers of its decomposition are similar to those for plant litter (e.g., 29importance of abiotic degradation through UV radiation), the magnitude of lichen decomposition 30 rates and whether they will be affected by climate change. Here we report results from a litter 31 decomposition experiment carried out with two biocrust-forming lichens (Diploschistes 32 diacapsis and Cladonia convoluta) in central Spain. We evaluated how lichen decomposition 33 was affected by warming, rainfall exclusion and the combination of both. We also manipulated 34 the incidence of UV radiation using mesh material that blocked 10% or 90% of incoming UV 35 radiation. Our results indicate that lichens decompose as fast as some plants typical of the region 36 (k~0.3) and that the chemical composition of their thallus drives litter decomposition rates. 37Warming increased decomposition rates of both lichen species, and mediated the effects of 38 photodegradation. While UV exposure accelerated the decomposition of D. diacapsis, it slowed 39 down that of C. convoluta. Our results indicate that biocrust-forming lichens can decompose in 40 the field at a rate similar to that of vascular plants, and that this process will be affected by 41 warming. Our findings further highlight the need of incorporating biocrusts into carbon cycling 42 models to better understand and forecast climate change impacts on terrestrial biogeochemistry. 43 Lichen litter decomposition 3 44

show abstract

Section: Discussionmentioning

confidence: 99%

Litter decomposition rates of biocrust-forming lichens are similar to that of vascular plants and are affected by warming in a semiarid grassland

Berdugo

Mendoza-Aguilar

Rey

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

Relative humidity predominantly determines long-term biocrust-forming lichen survival under climate change

Baldauf

Porada

Raggio

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

15 1. Manipulative experiments show a decrease in dryland biological soil crust cover and al-16 tered species composition under climate change. However, the underlying mechanisms are 17 not fully understood, and long-term interacting effects of different drivers are largely un-18 known due to the short-term nature of the studies conducted so far. 192. We addressed this gap and successfully parameterized a process-based model for the bi-20 ocrust-forming lichen Diploschistes diacapsis as a common and globally distributed rep-21 resentative of biocrust communities to quantify how changing atmospheric CO2, tempera-22 ture, rainfall amount and relative humidity affect its photosynthetic activity and cover. We 23 also mimicked a long-term manipulative climate change experiment to understand the 24 mechanisms underlying observed patterns in the field. 25 3. The model reproduced observed experimental findings: warming reduced lichen cover 26 whereas less rainfall had no effect. This warming effect was caused by the associated de-27 crease in relative humidity and non-rainfall water inputs as major water sources for li-28 chens. Warming alone, however, increased cover because higher temperatures promoted 29 photosynthesis during the cool morning hours with high lichen activity. When combined, 30 climate variables showed non-additive effects on lichen cover, and fertilization effects of 31 CO2 leveled off with decreasing levels of relative humidity. 32 4. Synthesis. Our results show that a decrease in relative humidity, rather than an increase in 33 temperature may be the key factor for the survival of dryland lichens under climate 34 change and that CO2 fertilization effects might be offset by a reduction in non-rainfall 35 water inputs in the future. Because of a global trend towards warmer and thus drier air, 36 3 this will affect lichen-dominated dryland biocrust communities and their role in regulat-37 ing ecosystem functions, worldwide. 38 39 40

show abstract

Abiotic and biotic drivers underly short- and long-term soil respiration responses to experimental warming in a dryland ecosystem

Cited by 2 publications

References 74 publications

Litter decomposition rates of biocrust-forming lichens are similar to that of vascular plants and are affected by warming in a semiarid grassland

Litter decomposition rates of biocrust-forming lichens are similar to that of vascular plants and are affected by warming in a semiarid grassland

Relative humidity predominantly determines long-term biocrust-forming lichen survival under climate change

Contact Info

Product

Resources

About