Laboratory-based techniques for assessing the functional traits of biocrusts
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Background and aims
Functional traits are increasingly being used to assess the degree to which ecosystems maintain key processes. The functional traits of vascular plants are well-documented but those of non-vascular plants are poorly known. We describe a comprehensive methodology to measure the functional traits of soil-borne lichens, mosses and liverworts making up biocrust (biological soil crust) communities.
We collected 40 biocrust taxa from across 10,000 km2 of eastern Australia, and measured eight functional traits using a combination of mensurative studies and laboratory-based experiments. These traits were sediment capture, absorptivity, root (or rhizine) length, height, and the activity of four enzymes involved in key nutrient cycles; β-glucosidase, β-D-cellobiosidase, N-acetyl-β-glucosaminidase and phosphatase.
Taxa were distributed across a broad range of trait values. Sediment capture values ranged from 2 % in the crustose lichen Diploschistes thunbergianus to 83 % in the tall moss Triquetrella papillata. The highest absorptivity value was observed in the moss Bartramia hampeana ssp. hampei, which was able to absorb 12.9 times its dry mass in water, while the lowest value, 0.3, was observed in Diploschistes thunbergianus. Multivariate analyses revealed that biocrust morphological groups differed significantly in their functional profiles.
Our results indicate that biocrust taxa vary greatly in their functional traits and that morphological groups explain, in part, the ability of biocrusts to sequester resources (sediment, moisture) and to undertake key processes associated with the cycling of carbon, nitrogen and phosphorus. This methodology will enhance our understanding of ecosystem functioning in drylands where biocrusts make up a large component of the surface cover and provide a range of ecosystem goods and services.
KeywordsBiocrust Functional traits Ecosystem function Drylands Morphogroups
We are grateful to Manuel Delgado-Baquerizo for his assistance in developing the enzyme methods. We also thank Samantha Travers, Henri Dubourdieu, Sarah Barkman and Jason Chan, who helped to prepare samples. We are grateful to Martin Mallen-Cooper for helping to design and construct the portable wind tunnel used in this study.
- Abràmoff MD, Magalhães PJ, Ram SJ (2004) Image processing with ImageJ. Biophoton Int 11:36–42Google Scholar
- Bell CW, Fricks BE, Rocca JD, et al. (2013) High-throughput fluorometric measurement of potential soil extracellular enzyme activities. J Vis Exp:e50961Google Scholar
- Buck WR, Vitt DH (2006) Key to the Genera of Australian Mosses. Flora of Australia Volume 51, Australian Biological Resources Study, Canberra, 2002).Google Scholar
- Bureau of Meteorology (2015) Bureau of Meteorology, Australian Government http://www.bom.gov.au/. Accessed 20 Aug 2015.
- Campbell DH (1904) Resistance of drought by liverworts. Torreya 4:81–86Google Scholar
- Castillo AP, Maestre FT, Palacios P, et al. (2008) Evaluando el papel funcional de la biodiversidad y el patrón espacial: Una aproximación experimental utilizando la costra biológica como modelo. In: Maestre FT, Escudero A, Bonet A (eds) Introducción al análisis espacial de datos en ecología y ciencias ambientales: métodos y aplicaciones. Universidad Rey Juan Carlos, Móstoles, pp. 617–635Google Scholar
- Catcheside DG (1980) Mosses of South Australia. S.A. Govt, Printer, AdelaideGoogle Scholar
- Chown S, Scholtz C (1989) Cryptogam herbivory in Curculionidae (Coleoptera) from the sub-antarctic Prince Edward Islands. The Coleopterists’ Bulletin 43:165–169Google Scholar
- Daly GT (1970) Bryophyte and lichen indicators of air pollution in Christchurch, New Zealand. Proceedings of the New Zealand Ecological Society 17:70–79Google Scholar
- Filson RB, Rogers RW (1979) Lichens of South Australia. Government Printer, South AustraliaGoogle Scholar
- Kunstler G, Falster D, Coomes DA, et al. (2016) Plant functional traits have globally consistent effects on competition. Nature 529:204–207.Google Scholar
- Larney FJ, Bullock MS, Janzen HH, et al. (1998) Wind erosion effects on nutrient redistribution and soil productivity. J Soil Water Conserv 53:133–140Google Scholar
- Maechler M, Rousseeuw P, Struyf A, et al. (2015) cluster: Cluster Analysis Basics and Extensions. R package version 2.0.3. http://CRAN.R-project.org/package=cluster. Accessed 10 Aug 2015.
- McCarthy PM (1991) The lichen genus Endocarpon Hedwig in Australia. Lichenologist 23:27–52Google Scholar
- McCarthy PM (2006). Checklist of Australian liverworts and Hornworts. Australian Biological Resources Study, Canberra Viewed 06 March 2016. http://www.anbg.gov.au/abrs/liverwortlist/liverworts_intro.html
- McCarthy PM (2015) Checklist of Australian Lichenicolous fungi. Australian Biological Resources Study, Canberra Version 10 December 2015. http://www.anbg.gov.au/abrs/lichenlist/Lichenicolous_Fungi.html
- Michel P, Payton IJ, Lee WG, During HJ (2013) Impact of disturbance on above-ground water storage capacity of bryophytes in New Zealand indigenous tussock grassland ecosystems. N Z J Ecol 37:114–126Google Scholar
- Oksanen J, Blanchet FG, Kindt R, et al. (2015) Vegan: community ecology package. R Package Version 2.3. http://CRAN.R-project.org/package=vegan. Accessed 10 Aug 2015.
- Rogers R, Lange R (1972) Soil surface lichens in arid and subarid South-Eastern Australia. I Introduction and floristics. Aust J Bot 20:197–213Google Scholar
- Scott GAM (1985) Southern Australian liverworts. Australian Government Publishing Service, CanberraGoogle Scholar
- Scott GAM, Stone IG (1976) The mosses of Southern Australia. Australian Government Publishing Service, CanberraGoogle Scholar
- White RP, Nackoney J (2003) Drylands, people, and ecosystem goods and services: a Web-based Geospatial analysis. World Resources Institute. http://pdf.wri.org/drylands. Accessed 30 Jan 2012.