Warming reduces the growth and diversity of biological soil crusts in a semi-arid environment: implications for ecosystem structure and functioning

Biological soil crusts (BSCs) are key biotic components of dryland ecosystems worldwide that control many functional processes, including carbon and nitrogen cycling, soil stabilization and infiltration. Regardless of their ecological importance and prevalence in drylands, very few studies have explicitly evaluated how climate change will affect the structure and composition of BSCs, and the functioning of their constituents. Using a manipulative experiment conducted over 3 years in a semi-arid site from central Spain, we evaluated how the composition, structure and performance of lichen-dominated BSCs respond to a 2.4°C increase in temperature, and to an approximately 30 per cent reduction of total annual rainfall. In areas with well-developed BSCs, warming promoted a significant decrease in the richness and diversity of the whole BSC community. This was accompanied by important compositional changes, as the cover of lichens suffered a substantial decrease with warming (from 70 to 40% on average), while that of mosses increased slightly (from 0.3 to 7% on average). The physiological performance of the BSC community, evaluated using chlorophyll fluorescence, increased with warming during the first year of the experiment, but did not respond to rainfall reduction. Our results indicate that ongoing climate change will strongly affect the diversity and composition of BSC communities, as well as their recovery after disturbances. The expected changes in richness and composition under warming could reduce or even reverse the positive effects of BSCs on important soil processes. Thus, these changes are likely to promote an overall reduction in ecosystem processes that sustain and control nutrient cycling, soil stabilization and water dynamics.

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Faculty Opinions recommendation of Warming reduces the growth and diversity of biological soil crusts in a semi-arid environment: implications for ecosystem structure and functioning.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717963915.793465669 ◽

2012 ◽

Author(s):

Eric Post

Keyword(s):

Arid Environment ◽

Biological Soil Crusts ◽

Ecosystem Structure ◽

Soil Crusts ◽

Ecosystem Structure And Functioning ◽

Semi Arid

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Applying a field spectroscopy technique for assessing successional trends of biological soil crusts in a semi-arid environment

Journal of Arid Environments ◽

10.1016/j.jaridenv.2007.01.004 ◽

2007 ◽

Vol 70 (3) ◽

pp. 463-477 ◽

Cited By ~ 40

Author(s):

E. Zaady ◽

A. Karnieli ◽

M. Shachak

Keyword(s):

Arid Environment ◽

Biological Soil Crusts ◽

Spectroscopy Technique ◽

Soil Crusts ◽

Field Spectroscopy ◽

Semi Arid

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Development of artificial moss-dominated biological soil crusts and their effects on runoff and soil water content in a semi-arid environment

Journal of Arid Environments ◽

10.1016/j.jaridenv.2015.02.017 ◽

2015 ◽

Vol 117 ◽

pp. 75-83 ◽

Cited By ~ 32

Author(s):

Bo Xiao ◽

Yunge Zhao ◽

Qinghai Wang ◽

Cui Li

Keyword(s):

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Arid Environment ◽

Biological Soil Crusts ◽

Soil Crusts ◽

Semi Arid

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Assessment the climate change impact on the future evapotranspiration and flows from a semi-arid environment

Arabian Journal of Geosciences ◽

10.1007/s12517-020-5065-x ◽

2020 ◽

Vol 13 (2) ◽

Cited By ~ 4

Author(s):

Salah Ouhamdouch ◽

Mohammed Bahir ◽

Driss Ouazar ◽

Abdelmalek Goumih ◽

Kamel Zouari

Keyword(s):

Climate Change ◽

Climate Change Impact ◽

Arid Environment ◽

The Future ◽

Change Impact ◽

Semi Arid

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Germination strategies under climate change scenarios along an aridity gradient

Journal of Plant Ecology ◽

10.1093/jpe/rtaa035 ◽

2020 ◽

Vol 13 (4) ◽

pp. 470-477

Author(s):

Alexander Zogas ◽

Evsey Kosman ◽

Marcelo Sternberg

Keyword(s):

Climate Change ◽

Seed Banks ◽

Arid Ecosystems ◽

Annual Rainfall ◽

Strong Impact ◽

Climate Change Scenarios ◽

Aridity Gradient ◽

Soil Seed Banks ◽

Seed Germinability ◽

Semi Arid

Abstract Aims Climate change in the eastern Mediterranean region will have a strong impact on ecosystem functioning and plant community dynamics due to a reduction in annual rainfall and increased variability. We aim to understand the role of seed banks as potential buffers against climatic uncertainty determined by climate change. Methods We examined germination strategies of 18 common species present along an aridity gradient. Data were obtained from soil seed banks germinated during nine consecutive years from arid, semi-arid, Mediterranean and mesic Mediterranean ecosystems. At the semi-arid and Mediterranean sites, rainfall manipulations simulating 30% drought and 30% rainfall increase were applied. Germination strategies were tested under optimal irrigation conditions during three consecutive germination seasons to determine overall seed germinability in each soil sample. Changes in germination strategy were examined using a novel statistical approach that considers the climatic and biotic factors that may affect seed germinability. Important Findings The results showed that dominant species controlled their germination fractions by producing seeds with a different yearly germination fraction probability. The amount of rainfall under which the seeds were produced led to two major seed types with respect to germinability: high germinability, seeds leading to transient seed banks, and low germinability, seeds leading to persistent seed banks. We conclude that differential seed production among wet and dry years of both seed types creates a stable balance along the aridity gradient, enabling the soil seed bank to serve as a stabilizing mechanism buffering against rainfall unpredictability. Additionally, we present a general model of germination strategies of dominant annual species in Mediterranean and arid ecosystems that strengthens the notion of soil seed banks as buffers against climatic uncertainty induced by climate change in the region.

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Climate change and physical disturbance cause similar community shifts in biological soil crusts

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1509150112 ◽

2015 ◽

Vol 112 (39) ◽

pp. 12116-12121 ◽

Cited By ~ 118

Author(s):

Scott Ferrenberg ◽

Sasha C. Reed ◽

Jayne Belnap

Keyword(s):

Climate Change ◽

Community Structure ◽

Summer Rainfall ◽

Community Change ◽

Biological Soil Crusts ◽

Physical Disturbance ◽

Precipitation Frequency ◽

Soil Crusts ◽

Altered Precipitation

Biological soil crusts (biocrusts)—communities of mosses, lichens, cyanobacteria, and heterotrophs living at the soil surface—are fundamental components of drylands worldwide, and destruction of biocrusts dramatically alters biogeochemical processes, hydrology, surface energy balance, and vegetation cover. Although there has been long-standing concern over impacts of physical disturbances on biocrusts (e.g., trampling by livestock, damage from vehicles), there is increasing concern over the potential for climate change to alter biocrust community structure. Using long-term data from the Colorado Plateau, we examined the effects of 10 y of experimental warming and altered precipitation (in full-factorial design) on biocrust communities and compared the effects of altered climate with those of long-term physical disturbance (>10 y of replicated human trampling). Surprisingly, altered climate and physical disturbance treatments had similar effects on biocrust community structure. Warming, altered precipitation frequency [an increase of small (1.2 mm) summer rainfall events], and physical disturbance from trampling all promoted early successional community states marked by dramatic declines in moss cover and increases in cyanobacteria cover, with more variable effects on lichens. Although the pace of community change varied significantly among treatments, our results suggest that multiple aspects of climate change will affect biocrusts to the same degree as physical disturbance. This is particularly disconcerting in the context of warming, as temperatures for drylands are projected to increase beyond those imposed as treatments in our study.

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A New Application of Random Forest Algorithm to Estimate Coverage of Moss-Dominated Biological Soil Crusts in Semi-Arid Mu Us Sandy Land, China

Remote Sensing ◽

10.3390/rs11111286 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1286 ◽

Cited By ~ 3

Author(s):

Xiang Chen ◽

Tao Wang ◽

Shulin Liu ◽

Fei Peng ◽

Atsushi Tsunekawa ◽

...

Keyword(s):

Random Forest ◽

Biological Soil Crusts ◽

Data Availability ◽

Sandy Land ◽

Desert Ecosystems ◽

Mu Us Sandy Land ◽

Soil Crusts ◽

Band Combinations ◽

Semi Arid ◽

Sentinel 2

Biological soil crusts (BSCs) play an essential role in desert ecosystems. Knowledge of the distribution and disappearance of BSCs is vital for the management of ecosystems and for desertification researches. However, the major remote sensing approaches used to extract BSCs are multispectral indices, which lack accuracy, and hyperspectral indices, which have lower data availability and require a higher computational effort. This study employs random forest (RF) models to optimize the extraction of BSCs using band combinations similar to the two multispectral BSC indices (Crust Index-CI; Biological Soil Crust Index-BSCI), but covering all possible band combinations. Simulated multispectral datasets resampled from in-situ hyperspectral data were used to extract BSC information. Multispectral datasets (Landsat-8 and Sentinel-2 datasets) were then used to detect BSC coverage in Mu Us Sandy Land, located in northern China, where BSCs dominated by moss are widely distributed. The results show that (i) the spectral curves of moss-dominated BSCs are different from those of other typical land surfaces, (ii) the BSC coverage can be predicted using the simulated multispectral data (mean square error (MSE) < 0.01), (iii) Sentinel-2 satellite datasets with CI-based band combinations provided a reliable RF model for detecting moss-dominated BSCs (10-fold validation, R2 = 0.947; ground validation, R2 = 0.906). In conclusion, application of the RF algorithm to the Sentinel-2 dataset can precisely and effectively map BSCs dominated by moss. This new application can be used as a theoretical basis for detecting BSCs in other arid and semi-arid lands within desert ecosystems.

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