Biodiversity & Conservation: Special issue on biocrusts out now!

Hi! It's me your prodigal blogger. It's been a long hiatus…but here's some news for you:

Biodiversity & Conservation Volume 23, Issue 7 (June 2014) is a special issue entitled "Biological soil crusts in a changing world", edited by Fernando Maestre, Leopoldo Sancho & Burkhard Budel. This issue was based on the Biocrust 2013 conference in Madrid. It features 14 invited contributions from the conference, including one from me & collaborators which was one of the funnest writing assignments I've taken on. A few of the papers are open access too.

http://link.springer.com/journal/10531/23/7/page/1

Ecological Processes paper collection on biocrusts

There's so much crust news I can't possibly keep up with posting. This is one I should have addressed weeks ago. Bettina Weber and Jayne Belnap organized a crust session on biocrusts in last summer's Ecological Society of America Meeting in Portland, all authors were asked to contribute to this special issue (or paper collection, the open-access version). Some of the talks turned into papers, and other contributors were invited to fill in the gaps. It's an eclectic and high quality collection that is truly international.

Ecological Processes is a new Springer open access journal. All papers are free! Follow the links below to read the papers or download pdf's. Also, check back, I believe more papers are coming.

Biological soil crusts: their diversity, functional ecology and management.

Edited by: Dr Jayne Belnap, Dr Bettina Weber It has only recently been recognized that biological soil crusts (BSC) are a critical component of dryland ecosystems, contributing to the diversity, functionality and nutrient cycling of these regions worldwide. Formed by cyanobacteria, algae, lichens, fungi and bacteria in varying proportions, BSC grow within the uppermost millimeters of the soil, fulfilling a variety of ecosystem services. With their filaments BSC organisms glue together soil particles, thus effectively preventing erosion by both wind and water. BSC organisms in general and nitrogen-fixing cyanobacteria in particular, add nutrients to nutrient-poor desert soils, thus promoting the establishment and growth of vascular plants. Their relevance and impact on global carbon and nitrogen cycles is just starting to be considered. During the last decade, studies on BSC have intensified and diversified, creating a unique and growing research community.Collection published: 23 February 2013Last updated: 16 May 2013
Belnap J, Weber B- Biological soil crusts as an integral component of desert environments. 
Marusenko Y, Bates S, Anderson I, Johnson S, Soule T, Garcia-Pichel F. Ammonia-oxidizing archaea and bacteria are structured by geography in biological soil crusts of North American arid lands.

Weber B, Wessels DCJ, Deutschewitz, Dojani S, Reichenberger H, Budel B. Ecological characterization of soil-inhabiting and hypolithic soil crusts within the Knersvlakte, South Africa.

Budel B, Vivas M, Lange OL. Lichen species dominance and the resulting photosynthetic behavior of Sonoran Desert soil crust types (Baja California, Mexico).

Dettweiler-Robinson E, Ponzetti JM, Bakker JD. Long-term changes in biological soil crust cover and composition.

Peterson EB. Regional-scale relationship among biological soil crusts, invasive annual grasses, and disturbance.

Beraldi-Campesi H. Early life on land and the first terrestrial ecosystems.

Theme Issue 'Impacts of global environmental change on drylands: from ecosystem structure and functioning to poverty alleviation'

Out today, a special issue of Philosophical Transactions "Impacts of global environmental chang on drylands: from ecosystem structure and functioning to poverty alleviation" edited by Fernando Maestre and Roberto Salguero-Gómez.

Below are the 2 most biocrust focused abstracts, but I recommend the whole issue as it contains submission by the editors, Andrew Dougill, and Elisabeth Huber-Sannwald. Happy reading.

• Andrew D. Thomas

Research article: Impact of grazing intensity on seasonal variations in soil organic carbon and soil CO₂ efflux in two semiarid grasslands in southern Botswana Phil. Trans. R. Soc. B November 19, 2012 367 1606 3076-3086; doi:10.1098/rstb.2012.0102 1471-2970 

 Biological soil crusts (BSCs) are an important source of organic carbon, and affect a range of ecosystem functions in arid and semiarid environments. Yet the impact of grazing disturbance on crust properties and soil CO₂ efflux remain poorly studied, particularly in African ecosystems. The effects of burial under wind-blown sand, disaggregation and removal of BSCs on seasonal variations in soil CO₂ efflux, soil organic carbon, chlorophyll a and scytonemin were investigated at two sites in the Kalahari of southern Botswana. Field experiments were employed to isolate CO₂ efflux originating from BSCs in order to estimate the C exchange within the crust. Organic carbon was not evenly distributed through the soil profile but concentrated in the BSC. Soil CO₂ efflux was higher in Kalahari Sand than in calcrete soils, but rates varied significantly with seasonal changes in moisture and temperature. BSCs at both sites were a small net sink of C to the soil. Soil CO₂ efflux was significantly higher in sand soils where the BSC was removed, and on calcrete where the BSC was buried under sand. The BSC removal and burial under sand also significantly reduced chlorophyll a, organic carbon and scytonemin. Disaggregation of the soil crust, however, led to increases in chlorophyll a and organic carbon. The data confirm the importance of BSCs for C cycling in drylands and indicate intensive grazing, which destroys BSCs through trampling and burial, will adversely affect C sequestration and storage. Managed grazing, where soil surfaces are only lightly disturbed, would help maintain a positive carbon balance in African drylands. 

• Cristina Escolar,
• Isabel Martínez,
• Matthew A. Bowker,
• and Fernando T. Maestre

Research article: Warming reduces the growth and diversity of biological soil crusts in a semi-arid environment: implications for ecosystem structure and functioning Phil. Trans. R. Soc. B November 19, 2012 367 1606 3087-3099; doi:10.1098/rstb.2011.0344 1471-2970 

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.