RT journal article
T1 Cyanolichen crusts are a key predictor of nitrogen cycling and fixation potential in soils from semiarid Mediterranean ecosystems
A1 Ochoa Hueso, Raúl
A1 Delgado Baquerizo, Manuel
A1 Estebanez, Belén
A1 Homet Gutierrez, Pablo
A2 Biología
K1 Biocrusts
K1 Biological nitrogen fixation
K1 Cyanolichens
K1 Mediterranean shrublands
K1 N cycle
AB Biocrusts play a key role in supporting nitrogen (N) cycling and bioavailability in drylands. However, the taxon-specific contribution of biocrust constituents to soil N fixation and bioavailability is far less understood. We measured the composition of soil-associated biocrusts and soil pigment content in a semiarid shrubland from central Spain, and evaluated the potential regulatory capacity of biocrusts, and their forming constituents (mosses, lichens, and cyanobacteria) over the N cycle (storage, bioavailability, and processing). We found that key biocrust species contributed to explain N fixation potential and availability. In particular, the cyanolichen Collema was positively correlated with N fixation potential, as was total cyanobacterial abundance, and, in particular, the morphotypic genera Microcoleus , and Leptolyngbya . Also, the cyanobacterial morphotype Microcoleus was associated with ammonium accumulation and negatively with ammonification potential. Total biocrust cover and the cover of the moss Tortella squarrosa were negatively correlated with soil N content in this relatively low-fertility site, and positively with N fixation potential. Our results underline the taxon-specific contributions of biocrust components, such as Collema , which emerged as a key predictor of N bioavailability. We provide a novel empirical demonstration of how different biocrust components play distinct roles in N cycling processes at the local scale, by promoting or inhibiting N fixation and/or storing organic and inorganic N, thus contributing to the efficient cycling of this critical element in the typically N-poor Mediterranean ecosystems of central Spain.
PB Elsevier
SN 1873-1511
YR 2026
FD 2026-03-26
LK http://hdl.handle.net/10498/40487
UL http://hdl.handle.net/10498/40487
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 08-nov-2026