Biotic communities cannot mitigate the negative effects of grazing on multiple ecosystem functions and services in an arid shrubland
- 961 Downloads
Dryland biotic communities (plants and biocrusts) are known to maintain multiple functions (multifunctionality) and services (multiservices) that decline with overgrazing by domestic livestock. Here, we evaluate the role of biotic communities in controlling the responses of multiple functions and services to grazing in an arid shrubland.
We compared nine ecosystem functions and services associated with carbon and nitrogen cycling, and water infiltration at grazed and ungrazed sites in eastern Australia. We hypothesized that overgrazing would reduce individual functions, but that effects on multifunctionality and multiservices would be tempered by shrubs, vascular plants and biocrusts.
Grazing reduced biocrust cover, soil phosphatase, β-glucosidase and potential mineralization, but not plant richness, soil respiration, infiltration measures nor dissolved inorganic N. In our models, grazing had the largest and most negative effects on multifunctionality and multiservices. Structural equation modelling showed that grazing reduced biocrust cover. Unlike the univariate analyses, grazing reduced plant cover and suppressed any positive effect of these biotic communities on multifunctionality and multiservices.
Our results suggest that any positive buffering by plant richness, shrubs and plant cover on multifunctions or multiservices will not offset the negative effects of grazing. Strategies to improve functionality of arid shrublands should focus on the management of total grazing pressure.
KeywordsGrazing Biocrust Chenopod shrublands Soil function Ecosystem services Infiltration Respiration Carbon cycling
Jing Zhang received support from the National Basic Research Program (2014CB954200) and National Natural Scientific Foundation (41401117) of China to visit Australia, and a Fowlers Gap Arid Zone Research Station Scholarship for travel and living allowances while in Australia. We are extremely grateful for the support provided by Dr. Keith Leggett from the University of NSW Arid Zone Research Station at Fowlers Gap.
- Allen SE, Grimshaw HM, Rowland AP (1986) Chemical analysis. Methods in plant ecology. Blackwell Scientific, OxfordGoogle Scholar
- Bradford MA, Wood SA, Bardgett RD, Black HIJ, Bonkowski M, Eggers T, Grayston SJ, Kandeler E, Manning P, Setälä H, Jones TH (2014) Discontinuity in the responses of ecosystem processes and multifunctionality to altered soil community composition. Proc Natl Acad Sci 111:14478–14483CrossRefPubMedPubMedCentralGoogle Scholar
- Delgado-Baquerizo M, Gallardo A, Covelo F, Prado-Comesaña A, Ochoa V, Maestre FT (2015) Differences in thallus chemistry are related to species-specific effects of biocrust-forming lichens on soil nutrients and microbial communities. Funct Ecol 29:1087–1098Google Scholar
- Eldridge DJ, Tozer ME (1997) A practical guide to soil lichens and bryophytes of Australia’s dry country. Department of Land and Water Conservation, SydneyGoogle Scholar
- Eldridge DJ, Beecham G, Grace J (2015) Do shrubs reduce the adverse effects of grazing on soil properties? Ecohydrology. doi: 10.1002/eco.1600
- Eldridge DJ, Poore AGB, Ruiz-Colmenero M, Letnic M, Soliveres S (2016). Ecosystem structure, function and composition in rangelands are negatively affected by livestock grazing. Ecol Applic (in press)Google Scholar
- Gamfeldt L, Snall T, Bagchi R, Jonsson M, Gustafsson L, Kjellander P, Ruiz-Jaen MC, Froberg M, Stendahl J, Philipson CD, Mikusinski G, Andersson E, Westerlund B, Andren H, Moberg F, Moen J, Bengtsson J (2013) Higher levels of multiple ecosystem services are found in forests with more tree species. Nat Commun 4:1340CrossRefPubMedPubMedCentralGoogle Scholar
- Margarey ER (1999) The effect of sheep grazing on lizard assemblages in the New South Wales arid zone. Unpublished BSc (Hons) thesis, School of Biological Science. Sydney, University of New South Wales, p 54Google Scholar
- Miller JED, Damschen E (2013). Relationships among biological soil crusts, environment, and vascular plants in Ozark sandstone glades. Proc. 98th ESA Annual Convention, Minneapolis, MinnesotaGoogle Scholar
- Tabatabai MA (1982) Methods of soil analyses part 2. American Society of Agronomy, MadisonGoogle Scholar
- World Bank (2008) World development report, agriculture for development. World Bank, WashingtonGoogle Scholar