Subtropical native grasslands may not require fire, mowing or grazing to maintain native-plant diversity
Roderick J. Fensham A B D , Donald W. Butler A , Boris Laffineur A B , Harry J. MacDermott A B , John W. Morgan C and Jennifer L. Silcock A BA Queensland Herbarium, Department of Science, Information Technology and Innovation, Brisbane Botanic Gardens, Mt Coot-tha Road, Toowong, Qld 4066, Australia.
B School of Biological Sciences, University of Queensland, St Lucia, Qld 4072, Australia.
C Department of Ecology, Environment and Evolution, La Trobe University, Bundoora, Vic. 3083, Australia.
D Corresponding author. Email: rod.fensham@qld.gov.au
Australian Journal of Botany 65(2) 95-102 https://doi.org/10.1071/BT16170
Submitted: 24 August 2016 Accepted: 23 December 2016 Published: 30 January 2017
Abstract
The rarity of native grasslands in agricultural districts heightens the requirement for optimal management to maintain diversity. Previous studies have suggested that disturbance is required to maintain species diversity in temperate Australian grasslands, but grasslands in semiarid environments do not have the same disturbance requirement. The current study examines the short-term responses to disturbance of subtropical grassland of the Darling Downs, south-eastern Queensland. We also compare temperate and subtropical grasslands in terms of biomass and rainfall. A field experiment was established with treatments, including burning in 2013, burning in 2014, burning in both years, mowing in both years, mowing and raking in both years, and an undisturbed control. Treatments were replicated at each of seven sampling stations in similar environments. The initial sampling after 2013 followed a wet summer and the final sampling was in 2015 after a dry summer. Non-metric multi-dimensional scaling showed that environmental differences, including silt content, soil pH, waterlogging and rainfall history, had more effect on the variation in species composition than did the treatments. The treatments engendered no significant response in species diversity. Of 51 widespread species, only four had a significant change in abundance in response to treatment. Herbaceous biomass was higher in temperate than subtropical grassland after a dry period. The grassland sward may be more open in the subtropics than in temperate grassland because of higher decomposition rates. A comparison of rainfall distribution between subtropical grassland and temperate grassland indicated that droughts are much more frequent in the former environments. These occasional droughts may provide a stress that reduces perennial grass cover, supplanting the requirement for grazing or fire to maintain plant diversity in grasslands. The management of grassland remnants in the subtropics, therefore, seems straightforward because there is little response in species richness or composition to disturbance. However, soil disturbance should be avoided to ensure that exotic species do not proliferate.
Additional keywords: Australia, disturbance, drought, management.
References
Arriaga FJ, Lowery B, Mays MD (2006) A fast method for determining soil particle size distribution using a laser instrument. Soil Science 171, 663–674.| A fast method for determining soil particle size distribution using a laser instrument.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XpsFGis7Y%3D&md5=0280b9dd7ab4e601be1b26fd129fae8dCAS |
Bostock PD, Holland AE (2007) (Eds) ‘Census of the Queensland flora 2007.’ (Queensland Herbarium, Environmental Protection Agency: Brisbane)
Calder JA, Wilson JB, Mark AF, Ward G (1992) Fire, succession and reserve management in a New-Zealand snow tussock grassland. Biological Conservation 62, 35–45.
| Fire, succession and reserve management in a New-Zealand snow tussock grassland.Crossref | GoogleScholarGoogle Scholar |
Cingolani AM, Noy-Meir I, Díaz S (2005) Grazing effects on rangeland diversity: a synthesis of contemporary models. Ecological Applications 15, 757–773.
| Grazing effects on rangeland diversity: a synthesis of contemporary models.Crossref | GoogleScholarGoogle Scholar |
Collins SL, Barber SC (1986) Effects of disturbance on diversity in mixed-grass prairie. Vegetatio 64, 87–94.
| Effects of disturbance on diversity in mixed-grass prairie.Crossref | GoogleScholarGoogle Scholar |
Collins SL, Knapp AK, Briggs JM, Blair JM, Steinauer EM (1998) Modulation of diversity by grazing and mowing in native tallgrass prairie. Science 280, 745–747.
| Modulation of diversity by grazing and mowing in native tallgrass prairie.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK1cXjtVyhtLc%3D&md5=73b322d714a4448c255013209b2f353bCAS |
Dorrough JW, Ash JE, Bruce S, McIntyre S (2007) From plant neighbourhood to landscape scales: how grazing modifies native and exotic plant species richness in grassland. Plant Ecology 191, 185–198.
| From plant neighbourhood to landscape scales: how grazing modifies native and exotic plant species richness in grassland.Crossref | GoogleScholarGoogle Scholar |
Eshel G, Levy GJ (2007) Comments on ‘A fast method for determining soil particle size distribution using a laser instrument’ by F. J. Arriaga, B. Lowery, and D. W. Mays. Soil Sci. 171:663–674 (2006). Soil Science 172, 413–415.
| Comments on ‘A fast method for determining soil particle size distribution using a laser instrument’ by F. J. Arriaga, B. Lowery, and D. W. Mays. Soil Sci. 171:663–674 (2006).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2sXlt1Kltrw%3D&md5=7a81f92798ff292860a81922e1df82b3CAS |
Fensham RJ (1997) Options for conserving large vegetation remnants in the Darling Downs, south Queensland. In ‘Conservation outside nature reserves’. (Eds P Hale, D Lamb) pp. 419–423. (Centre for Conservation Biology, University of Queensland: Brisbane)
Fensham RJ (1998a) The grassy vegetation of the Darling Downs, south-eastern Queensland, Australia. Floristics and grazing effects. Biological Conservation 84, 301–310.
| The grassy vegetation of the Darling Downs, south-eastern Queensland, Australia. Floristics and grazing effects.Crossref | GoogleScholarGoogle Scholar |
Fensham RJ (1998b) The grassy vegetation of the Darling Downs, south-eastern Queensland, Australia. Floristics and grazing effects. Biological Conservation 84, 301–310.
| The grassy vegetation of the Darling Downs, south-eastern Queensland, Australia. Floristics and grazing effects.Crossref | GoogleScholarGoogle Scholar |
Fensham RJ, Kirkpatrick JB (1989) The conservation of original vegetation remnants in the Midlands, Tasmania. Papers and Proceedings of the Royal Society of Tasmania 123, 229–246.
Fensham RJ, Holman JE, Cox MJ (1999) Plant species responses along a grazing disturbance gradient in Australian grassland. Journal of Vegetation Science 10, 77–86.
| Plant species responses along a grazing disturbance gradient in Australian grassland.Crossref | GoogleScholarGoogle Scholar |
Fensham RJ, Fairfax RJ, Dwyer JM (2010) Vegetation responses to the first 20 years of cattle grazing in an Australian desert. Ecology 91, 681–692.
| Vegetation responses to the first 20 years of cattle grazing in an Australian desert.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BC3c3ps1aquw%3D%3D&md5=8ec07b01a2f6e11a84365d911782af38CAS |
Fensham RJ, Wang J, Kilgour C (2015) The relative impacts of grazing, fire and invasion by buffel grass (Cenchrus ciliaris) on the floristic composition of a rangeland savanna ecosystem. The Rangeland Journal 37, 227–237.
| The relative impacts of grazing, fire and invasion by buffel grass (Cenchrus ciliaris) on the floristic composition of a rangeland savanna ecosystem.Crossref | GoogleScholarGoogle Scholar |
Fensham RJ, Butler DW, Fairfax RJ, Quintin AR, Dwyer JM (2016) Passive restoration of sub-tropical grassland after abandonment of cultivation. Journal of Applied Ecology 53, 274–283.
| Passive restoration of sub-tropical grassland after abandonment of cultivation.Crossref | GoogleScholarGoogle Scholar |
French M (1989) ‘Conflict on the Condamine. Aborigines and the European invasion.’ (USQ: Toowoomba)
Gibson N, Kirkpatrick JB (1989) Effects of the cessation of grazing on the grasslands and grassy woodlands of the central Plateau, Tasmania. Australian Journal of Botany 37, 55–63.
| Effects of the cessation of grazing on the grasslands and grassy woodlands of the central Plateau, Tasmania.Crossref | GoogleScholarGoogle Scholar |
Isbell RF (1996) ‘The Australian soil classification.’ (CSIRO Publishing: Melbourne)
Jeffrey SJ, Carter JO, Moodie KB, Beswick AR (2001) Using spatial interpolation to construct a comprehensive archive of Australian climate data. Environmental Modelling & Software 16, 309–330.
| Using spatial interpolation to construct a comprehensive archive of Australian climate data.Crossref | GoogleScholarGoogle Scholar |
Johnson C (2006) ‘Australia’s mammal extinctions. A 50 000 year history.’ (Cambridge University Press: Melbourne)
Kirkpatrick JB, McDougall K, Hyde M (1995) ‘Australia’s most threatened ecosystems. The southeastern lowland native grasslands.’ (Surrey Beatty: Sydney)
Knapp AK, Carroll CJW, Denton EM, La Pierre KJ, Collins SL, Smith MD (2015) Differential sensitivity to regional-scale drought in six central US grasslands. Oecologia 177, 949–957.
| Differential sensitivity to regional-scale drought in six central US grasslands.Crossref | GoogleScholarGoogle Scholar |
Koerner SE, Collins SL (2014) Interactive effects of grazing, drought, and fire on grassland plant communities in North America and South Africa. Ecology 95, 98–109.
| Interactive effects of grazing, drought, and fire on grassland plant communities in North America and South Africa.Crossref | GoogleScholarGoogle Scholar |
Leonard SWJ, Kirkpatrick JB (2004) Effects of grazing management and environmental factors on native grassland and grassy woodland, northern Midlands, Tasmania. Australian Journal of Botany 52, 529–542.
| Effects of grazing management and environmental factors on native grassland and grassy woodland, northern Midlands, Tasmania.Crossref | GoogleScholarGoogle Scholar |
Lewis T, Clarke PJ, Reid N, Whalley RDP (2008) Perennial grassland dynamics on fertile plains: is coexistence mediated by disturbance? Austral Ecology 33, 128–139.
| Perennial grassland dynamics on fertile plains: is coexistence mediated by disturbance?Crossref | GoogleScholarGoogle Scholar |
Lewis T, Clarke PJ, Whalley RDB, Reid N (2009) What drives plant biodiversity in the clay floodplain grasslands of NSW? The Rangeland Journal 31, 329–351.
| What drives plant biodiversity in the clay floodplain grasslands of NSW?Crossref | GoogleScholarGoogle Scholar |
Lewis T, Reid N, Clarke PJ, Whalley RDB (2010) Resilience of a high-conservation-value, semi-arid grassland on fertile clay soils to burning, mowing and ploughing. Austral Ecology 35, 464–481.
| Resilience of a high-conservation-value, semi-arid grassland on fertile clay soils to burning, mowing and ploughing.Crossref | GoogleScholarGoogle Scholar |
Lunt ID (1990) Impact of an autumn fire on a long-grazed Themeda trianda (kangaroo grass) grassland: implications for management of invaded, remnant vegetations. Victorian Naturalist 107, 45–51.
Morrison DA, Le Broque AF, Clarke PJ (1995) An assessment of some improved techniques for estimating the abundance (frequency) of sedentary organisms. Vegetatio 120, 131–145.
| An assessment of some improved techniques for estimating the abundance (frequency) of sedentary organisms.Crossref | GoogleScholarGoogle Scholar |
Moxham C, Dorrough J, Bramwell M, Farmilo BJ (2016) Fire exclusion and soil texture interact to influence temperate grassland flora in south-eastern Australia. Australian Journal of Botany 64, 417–426.
| Fire exclusion and soil texture interact to influence temperate grassland flora in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Pieri L, Bittelli M, Pisa PR (2006) Laser diffraction, transmission electron microscopy and image analysis to evaluate a bimodal Gaussian model for particle size distribution in soils. Geoderma 135, 118–132.
| Laser diffraction, transmission electron microscopy and image analysis to evaluate a bimodal Gaussian model for particle size distribution in soils.Crossref | GoogleScholarGoogle Scholar |
Prober S, Thiele KR, Koen TB (2004) Spring burns control exotic annual grasses in a temperate grassy woodland. Ecological Management & Restoration 5, 131–134.
| Spring burns control exotic annual grasses in a temperate grassy woodland.Crossref | GoogleScholarGoogle Scholar |
Rayment GE, Higginson FR (1992) ‘Australian laboratory handbook of soil and water chemical methods.’ (Inkata Press: Melbourne)
Samson F, Knopf F (1994) Prairie conservation in North-America. Bioscience 44, 418–421.
| Prairie conservation in North-America.Crossref | GoogleScholarGoogle Scholar |
Stuwe J, Parsons RF (1977) Themeda australis grasslands on the Basalt Plains Victoria: floristics and management effects. Australian Journal of Ecology 2, 467–476.
| Themeda australis grasslands on the Basalt Plains Victoria: floristics and management effects.Crossref | GoogleScholarGoogle Scholar |
Tix D, Charvat I (2005) Aboveground biomass removal by burning and raking increases diversity in a reconstructed prairie. Restoration Ecology 13, 20–28.
| Aboveground biomass removal by burning and raking increases diversity in a reconstructed prairie.Crossref | GoogleScholarGoogle Scholar |
Van Dyke F, Van Kley SE, Page CE, Van Beek JG (2004) Restoration efforts for plant and bird communities in tallgrass prairies using prescribed burning and mowing. Restoration Ecology 12, 575–585.
| Restoration efforts for plant and bird communities in tallgrass prairies using prescribed burning and mowing.Crossref | GoogleScholarGoogle Scholar |
Verrier FJ, Kirkpatrick JB (2005) Frequent mowing is better than grazing for the conservation value of lowland tussock grasssland at Pontville, Tasmania. Austral Ecology 30, 74–78.
| Frequent mowing is better than grazing for the conservation value of lowland tussock grasssland at Pontville, Tasmania.Crossref | GoogleScholarGoogle Scholar |
Williams NSG, Morgan JW, McCarthy MA, McDonnell MJ (2006) Local extinction of grassland plants: the landscape matrix is more important than patch attributes. Ecology 87, 3000–3006.
| Local extinction of grassland plants: the landscape matrix is more important than patch attributes.Crossref | GoogleScholarGoogle Scholar |
Willmott CJ, Feddema JJ (1992) A more rational climatic moisture index. The Professional Geographer 44, 84–88.
| A more rational climatic moisture index.Crossref | GoogleScholarGoogle Scholar |
Wilson N, Tickle PK, Gallant J, Dowling T, Read A (2011) ‘1 second SRTM Derived Hydrological Digital Elevation Model (DEM-H) version 1.0.’ (Geoscience Australia, Commonwealth of Australia: Canberra)
Zimmer HC, Turner VB, Mavromihalis J, Dorrough J, Moxham C (2010) Forb responses to grazing and rest management in a critically endangered Australian native grassland ecosystem. The Rangeland Journal 32, 187–195.
| Forb responses to grazing and rest management in a critically endangered Australian native grassland ecosystem.Crossref | GoogleScholarGoogle Scholar |