DOI: 10.5061/dryad.00000008j
title: Warming decreases desert ecosystem functioning by altering biocrusts in drylands

description: Warming and precipitation fluctuations are changing desert ecosystems in
 global drylands. However, the effects of climate change on keystone
 species such as cryptogamic biocrust in drylands remain relatively
 under-investigated, even though biocrusts play a vital role in desert
 ecosystems. We conducted a long-term experiment (14 years) to
 simulate the responses of two main types of biocrusts to warming coupled
 with reduction in precipitation that was achieved by open-top chambers
 (OTCs) to simulate the predicted warming and precipitation decreasing
 under climate change scenario. We also conduct a structural analysis to
 evaluate the resulting changes in desert ecosystem functioning (carbon and
 nitrogen cycling). Neither warming and corresponding rainfall
 reduction treatments had a negative effect on lichen species richness, but
 both treatments reduced lichen cover and biomass. The negative effects of
 warming on moss-dominated crusts were much greater than those on
 lichen-dominated crusts. Although mosses and lichens had varying degrees
 of response to warming, the loss of mosses and decreased lichen cover and
 biomass, as well as the shortening of the wet time, resulted in a
 reduction in carbon and nitrogen fixation, soil enzyme activity and
 water-holding capacity of biocrusts and topsoil. These impacts
 collectively change the water balance of drylands and weaken the
 hydrological and biogeochemical function of biocrusts.  Synthesis
 and applications: Results from this long-term experiment suggest that the
 ecosystem C and N cycling and water balance of global drylands may be
 highly impacted by climate change, in part because of the response of
 biocrusts, which contribute an important implication for both dryland
 restoration and earth system dynamics.
description: See published article in the Journal of Applied Ecology for
 method details.
description: This folder contains the datafiles for the article: Title: Warming
 decreases desert ecosystem functioning by altering biocrusts in drylands
 File list (files found within Data.zip) 1.
 Li\_et\_al\_2023\_data\_C\_N\_fixation 2. Li\_et\_al\_2023\_data\_Enzyme
 3. Li\_et\_al\_2023\_data\_MWHC 4. Li\_et\_al\_2023\_data\_Quadrat ###
 File descriptions Li\_et\_al\_2023\_data\_C\_N\_fixation: Change in annual
 carbon fixation (A) and nitrogen fixation (B) (mean ± SE, n=3) for both
 lichen- and moss-dominated crusts under two warming treatments and the
 control during the experimental period. Annual carbon fixation was
 calculated by the sum of wet time-weighted carbon fixation ability of all
 rainfall events. Annual nitrogen fixation was calculated by the sum of wet
 time-weighted nitrogen fixation ability of all rainfall events.
 Li\_et\_al\_2023\_data\_Enzyme: Changes in urease, invertase, catalase and
 dehydrogenase activity of lichen- and moss-dominated crust soil (0-5cm
 depth) after 6-, 10-, 12- and 14-year warming treatments and under the
 control. Li\_et\_al\_2023\_data\_MWHC: Changes in Maximum Water Holding
 Capacity under 0.5℃ and 1.5℃-warming treatment. MWHC: Maximum Water
 Holding Capacity (mg/cm2); Li\_et\_al\_2023\_data\_Quadrat: A design
 Quadrat indicating the Richness, Biomass and Cover of each Biocrust Type
 (lichen and moss) Treatment= ctrl: Control; Treatment= i05: 0.5℃-warming
 treatment; Treatment= i15: 1.5℃-warming treatment; C Fixation Ability:
 carbon fixation Ability; N Fixation Ability: nitrogen fixation Ability.
 SE, Standard Error.