After the fence: vegetation and topsoil condition in grazed, fenced and benchmark eucalypt woodlands of fragmented agricultural landscapes
Suzanne M. Prober A C , Rachel J. Standish B and Georg Wiehl A
+ Author Affiliations
- Author Affiliations
A CSIRO Ecosystem Sciences, Private Bag 5, Wembley, WA 6913, Australia.
B School of Plant Biology M090, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
C Corresponding author. Email: Suzanne.Prober@csiro.au
Australian Journal of Botany 59(4) 369-381 https://doi.org/10.1071/BT11026
Submitted: 25 January 2011 Accepted: 20 April 2011 Published: 9 June 2011
Abstract
Emerging ecological theory predicts that vegetation changes caused by introduction of livestock grazing may be irreversible after livestock are removed, especially in regions such as Australia that have a short evolutionary exposure to ungulate grazing. Despite this, fencing to exclude livestock grazing is the major tool used to restore vegetation in Australian agricultural landscapes. To characterise site-scale benefits and limitations of livestock exclusion for enhancing biodiversity in forb-rich York gum (Eucalyptus loxophleba Benth. subsp. loxophleba)–jam (Acacia acuminata Benth.) woodlands, we compared 29 fenced woodlands with 29 adjacent grazed woodlands and 11 little-grazed ‘benchmark’ woodlands in the Western Australian wheatbelt. We explored the following two hypotheses: (1) fencing to exclude livestock facilitates recovery of grazed woodlands towards benchmark conditions, and (2) without additional interventions after fencing, complete recovery of grazed woodlands to benchmark conditions is constrained by ecological or other limits. Our first hypothesis was supported for vegetation parameters, with fenced woodlands being more similar to benchmark woodlands in tree recruitment, exotic plant cover, native plant cover, native plant richness and plant species composition than were grazed woodlands. Further, exotic cover decreased and frequency of jam increased with time-since-fencing (2–22 years). However, we found no evidence that fencing led to decline in topsoil nutrient concentrations towards concentrations at benchmark sites. Our second hypothesis was also supported, with higher topsoil nutrient concentrations and exotic plant cover, and lower native plant richness in fenced than in benchmark woodlands, and different plant species composition between fenced and benchmark woodlands. Regression analyses suggested that recovery of native species richness is constrained by exotic species that persist after fencing, which in turn are more persistent at higher topsoil nutrient concentrations. We conclude that fencing to exclude livestock grazing can be valuable for biodiversity conservation. However, consistent with ecological theory, additional interventions are likely to be necessary to achieve some conservation goals or to promote recovery at nutrient-enriched sites.
References
Alvarez ME, Cushman JH (2002) Community-level consequences of a plant invasion: effects on three habitats in coastal California. Ecological Applications 12, 1434–1444.| Community-level consequences of a plant invasion: effects on three habitats in coastal California.Crossref | GoogleScholarGoogle Scholar |
Barrett GW, Freudenberger D, Drew A, Stol J, Nicholls AO, Cawsey EM (2008) Colonisation of native tree and shrub plantings by woodland birds in an agricultural landscape. Wildlife Research 35, 19–32.
| Colonisation of native tree and shrub plantings by woodland birds in an agricultural landscape.Crossref | GoogleScholarGoogle Scholar |
Beard JS (1990) ‘Plant life of Western Australia.’ (Kangaroo Press: Sydney)
Blair GJ, Chinoim N, Lefroy RB, Anderson GC, Crocker GJ (1991) A soil sulfur test for pasture and crops. Australian Journal of Soil Research 29, 619–626.
| A soil sulfur test for pasture and crops.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXmsFGjtr4%3D&md5=45606d445540bba8cdcc38118586267aCAS |
Briggs SV, Taws NM, Seddon JA, Vanzella B (2008) Condition of fenced and grazed remnant vegetation in inland catchments in south-eastern Australia. Australian Journal of Botany 56, 590–599.
| Condition of fenced and grazed remnant vegetation in inland catchments in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Cingolani AM, Noy-Meir I, Diaz S (2005) Grazing effects on rangeland diversity: a synthesis of current models. Ecological Applications 15, 757–773.
| Grazing effects on rangeland diversity: a synthesis of current models.Crossref | GoogleScholarGoogle Scholar |
Department of Industry and Resources (2001) ‘Atlas of mineral deposits and petroleum fields.’ (Geological Survey of Western Australia: Perth)
Dorrough J, Moxham C (2005) Eucalypt establishment in agricultural landscapes and implications for landscape-scale restoration. Biological Conservation 123, 55–66.
| Eucalypt establishment in agricultural landscapes and implications for landscape-scale restoration.Crossref | GoogleScholarGoogle Scholar |
Dorrough J, Moxham C, Turner V, Sutter G (2006) Soil phosphorus and tree cover modify the effects of livestock grazing on plant species richness in Australian grassy woodland. Biological Conservation 130, 394–405.
| Soil phosphorus and tree cover modify the effects of livestock grazing on plant species richness in Australian grassy woodland.Crossref | GoogleScholarGoogle Scholar |
Dorrough J, Scroggie MP (2008) Plant responses to agricultural intensification. Journal of Applied Ecology 45, 1274–1283.
| Plant responses to agricultural intensification.Crossref | GoogleScholarGoogle Scholar |
Duncan D, Moxham C, Read C (2007) ‘Effect of stock removal on woodlands in the Murray Mallee and Wimmera bioregions of Victoria.’ (Department of Sustainability and Environment: Melbourne)
Faith DP, Minchin PR, Belbin L (1987) Compositional dissimilarity as a robust measure of ecological distance. Vegetatio 69, 57–68.
| Compositional dissimilarity as a robust measure of ecological distance.Crossref | GoogleScholarGoogle Scholar |
Fox P (2001) Conservation of salmon gum (Eucalyptus salmonophloia F.Muell.) woodlands in the Western Australian wheatbelt: a consilience of biology, culture and perception. PhD Thesis, Murdoch University, Perth.
Greig-Smith P (1983) ‘Quantitative plant ecology.’ 3rd edn. (Blackwell Scientific Publications: Oxford, UK)
Hobbs RJ, Saunders DA (1993) ‘Re-integrating fragmented landscapes. Towards sustainable production and nature conservation.’ (Springer-Verlag: New York)
Hobbs RJ, Atkins L (1991) Interactions between annuals and woody perennials in a Western Australian nature reserve. Journal of Vegetation Science 2, 643–654.
| Interactions between annuals and woody perennials in a Western Australian nature reserve.Crossref | GoogleScholarGoogle Scholar |
Houlder DH, Hutchinson MF, Nix HA, McMahon JP (2001) ‘ANUCLIM user guide. Version 5.1.’ (Centre for Resource and Environmental Studies, Australian National University: Canberra)
Lenz TI, Facelli JM (2005) The role of seed limitation and resource availability in the recruitment of native perennial grasses and exotics in a South Australian grassland. Austral Ecology 30, 684–694.
| The role of seed limitation and resource availability in the recruitment of native perennial grasses and exotics in a South Australian grassland.Crossref | GoogleScholarGoogle Scholar |
Lenz TI, Facelli JM (2006) Correlations between environmental factors, the biomass of exotic annual grasses and the frequency of native perennial grasses. Australian Journal of Botany 54, 655–667.
| Correlations between environmental factors, the biomass of exotic annual grasses and the frequency of native perennial grasses.Crossref | GoogleScholarGoogle Scholar |
Ludwig J, Tongway D, Freudenberger D, Noble J, Hodgkinson K (Eds) (1997) ‘Landscape ecology, function and management: principles from Australia’s rangelands.’ (CSIRO: Melbourne)
Lunt I (1997) Germinable soil seed banks of anthropogenic native grasslands and grassy forest remnants in temperate south-eastern Australia. Plant Ecology 130, 21–34.
| Germinable soil seed banks of anthropogenic native grasslands and grassy forest remnants in temperate south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Lunt ID, Jansen A, Binns DL, Kenny SA (2007b) Long-term effects of exclusion of grazing stock on degraded herbaceous plant communities in a riparian Eucalyptus camaldulensis forest in south-eastern Australia. Austral Ecology 32, 937–949.
| Long-term effects of exclusion of grazing stock on degraded herbaceous plant communities in a riparian Eucalyptus camaldulensis forest in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Lunt ID, Eldridge DJ, Morgan JW, Witt GW (2007a) A framework to predict the effects of livestock grazing and grazing exclusion on conservation values in natural ecosystems in Australia. Australian Journal of Botany 55, 401–415.
| A framework to predict the effects of livestock grazing and grazing exclusion on conservation values in natural ecosystems in Australia.Crossref | GoogleScholarGoogle Scholar |
MacNally R (2006) Longer-term response to experimental manipulation of fallen timber on forest floors of floodplain forest in south-eastern Australia. Forest Ecology and Management 229, 155–160.
| Longer-term response to experimental manipulation of fallen timber on forest floors of floodplain forest in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Mack RN, Thompson JN (1982) Evolution in steppe with few large, hooved mammals. American Naturalist 119, 757–773.
| Evolution in steppe with few large, hooved mammals.Crossref | GoogleScholarGoogle Scholar |
Main BY (1992) Social history and impact on landscape (with Trayning: case history of a shire by D. Couper). In ‘Reintegrating fragmented landscapes towards sustainable production and nature conservation’. (Eds RJ Hobbs, DA Saunders) pp. 23–65. (Springer-Verlag: New York)
McCune B, Mefford MJ (1999) ‘PC-ORD. Multivariate analysis of ecological data. Version 4.’ (MjM Software Design: Gleneden Beach, Oregon
McLendon T, Redente EF (1991) Nitrogen and phosphorus effects on secondary succession dynamics on a semi-arid sagebrush site. Ecology 72, 2016–2024.
| Nitrogen and phosphorus effects on secondary succession dynamics on a semi-arid sagebrush site.Crossref | GoogleScholarGoogle Scholar |
Milchunas DG, Noy-Meir I (2002) Grazing refuges, external avoidance of herbivory and plant diversity. Oikos 99, 113–130.
| Grazing refuges, external avoidance of herbivory and plant diversity.Crossref | GoogleScholarGoogle Scholar |
Milchunas DG, Sala OE, Lauenroth WK (1988) A generalized model of effects of grazing by large herbivores on grassland community structure. American Naturalist 132, 87–106.
| A generalized model of effects of grazing by large herbivores on grassland community structure.Crossref | GoogleScholarGoogle Scholar |
Minchin PR (1989) ‘DECODA user’s manual.’ (Australian National University: Canberra)
Montague-Drake RM, Lindenmayer DB, Cunningham RB (2009) Factors affecting site occupancy by woodland bird species of conservation concern. Biological Conservation 142, 2896–2903.
| Factors affecting site occupancy by woodland bird species of conservation concern.Crossref | GoogleScholarGoogle Scholar |
Morgan J, Lunt ID (1999) Effects of time-since-fire on the tussock dynamics of a dominant grass (Themeda triandra) in a temperate Australian grassland. Biological Conservation 88, 379–386.
| Effects of time-since-fire on the tussock dynamics of a dominant grass (Themeda triandra) in a temperate Australian grassland.Crossref | GoogleScholarGoogle Scholar |
Natural Heritage Trust (2007) Natural Heritage Trust Annual Report 2005–6. (Commonwealth of Australia: Canberra)
Olff H, Ritchie ME (1998) Effects of herbivores on grassland plant diversity. Trends in Ecology & Evolution 13, 261–265.
| Effects of herbivores on grassland plant diversity.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BC3M7itF2iug%3D%3D&md5=d76690eb754400a206febb1d4b7a9fbaCAS | 21238294PubMed |
Pettit NE, Froend RH (2001) Long-term changes in the vegetation after the cessation of livestock grazing in Eucalyptus marginata (jarrah) woodland remnants. Austral Ecology 26, 22–31.
| Long-term changes in the vegetation after the cessation of livestock grazing in Eucalyptus marginata (jarrah) woodland remnants.Crossref | GoogleScholarGoogle Scholar |
Price JN, Wong NK, Morgan JW (2010) Recovery of understorey vegetation after release from a long history of sheep grazing in a herb-rich woodland. Austral Ecology 35, 505–514.
| Recovery of understorey vegetation after release from a long history of sheep grazing in a herb-rich woodland.Crossref | GoogleScholarGoogle Scholar |
Prober SM, Smith FP (2009) Enhancing biodiversity persistence in intensively-used agricultural landscapes: a synthesis of 30 years of research in the Western Australian wheatbelt. Agriculture Ecosystems & Environment 132, 173–191.
| Enhancing biodiversity persistence in intensively-used agricultural landscapes: a synthesis of 30 years of research in the Western Australian wheatbelt.Crossref | GoogleScholarGoogle Scholar |
Prober SM, Thiele KR (2005) Restoring Australia’s temperate grasslands and grassy woodlands: integrating function and diversity. Ecological Management & Restoration 6, 16–27.
| Restoring Australia’s temperate grasslands and grassy woodlands: integrating function and diversity.Crossref | GoogleScholarGoogle Scholar |
Prober SM, Wiehl G Resource heterogeneity and persistence of exotic annuals in long-ungrazed Mediterranean-climate woodlands. Biological Invasions.
| Resource heterogeneity and persistence of exotic annuals in long-ungrazed Mediterranean-climate woodlands.Crossref | GoogleScholarGoogle Scholar | 19777120PubMed |
Prober SM, Thiele KR, Lunt I (2002) Identifying ecological barriers to restoration in temperate grassy woodlands: soil changes associated with different degradation states. Australian Journal of Botany 50, 699–712.
| Identifying ecological barriers to restoration in temperate grassy woodlands: soil changes associated with different degradation states.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3sXlvFamsw%3D%3D&md5=9777d798dcb8668be3c27b5f026aba6eCAS |
Prober SM, Thiele KR, Lunt I, Koen TB (2005) Restoring ecological function in temperate grassy woodlands – manipulating soil nutrients, annual exotics and native perennial grasses through carbon supplements and spring burns. Journal of Applied Ecology 42, 1073–1085.
| Restoring ecological function in temperate grassy woodlands – manipulating soil nutrients, annual exotics and native perennial grasses through carbon supplements and spring burns.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28Xkt1aiuw%3D%3D&md5=32b6e9c01a7bee522c7ab50ce4112569CAS |
Prober SM, Lunt I, Morgan J (2009) Rapid internal plant-soil feedbacks lead to alternative stable states in temperate Australian grassy woodlands. In ‘New models for ecosystem dynamics and restoration’. (Eds K Suding, RJ Hobbs) pp. 156–168. (Island Press: Washington, DC)
Rayment GE, Higginson FR (1992) ‘Australian laboratory handbook of soil and water chemical methods.’ (Inkata Press: Melbourne)
Scougall SA, Majer JD, Hobbs RJ (1993) Edge effects in grazed and ungrazed Western Australian wheatbelt remnants in relation to ecosystem reconstruction. In ‘Nature conservation 3: reconstruction of fragmented ecosystems’. (Eds DA Saunders, RJ Hobbs, PR Ehrlich) pp. 163–178. (Surrey Beatty: Sydney)
Searle PL (1984) The Berthelot or indophenol reaction and its use in the analytical chemistry of nitrogen. Analyst (London) 109, 549–568.
| The Berthelot or indophenol reaction and its use in the analytical chemistry of nitrogen.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL2cXlsVartbk%3D&md5=a3366e98e1d3388d1da5fdcc6e711b11CAS |
Shepherd DP, Beeston GR, Hopkins AJM (2002) ‘Native vegetation in Western Australia: extent, type and status.’ (Department of Agriculture: Perth)
Smallbone L, Prober SM, Lunt ID (2007) Restoration treatments enhance early establishment of native forbs in a degraded grassy woodland. Australian Journal of Botany 55, 818–830.
| Restoration treatments enhance early establishment of native forbs in a degraded grassy woodland.Crossref | GoogleScholarGoogle Scholar |
Spooner PV, Briggs SV (2008) Woodlands on farms in southern NSW: a longer-term assessment of vegetation changes after fencing. Ecological Management & Restoration 9, 33–41.
| Woodlands on farms in southern NSW: a longer-term assessment of vegetation changes after fencing.Crossref | GoogleScholarGoogle Scholar |
Standish RJ, Cramer VA, Hobbs RJ, Kobryn HT (2006) Legacy of land-use evident in soils of Western Australia’s wheatbelt. Plant and Soil 280, 189–207.
| Legacy of land-use evident in soils of Western Australia’s wheatbelt.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XhslOrs7Y%3D&md5=dc7c4a7987b9f3d22e0a8aede5767c59CAS |
Standish RJ, Cramer VA, Hobbs RJ (2008) Land-use legacy and the persistence of invasive Avena barbata on abandoned farmland. Journal of Applied Ecology 45, 1576–1583.
| Land-use legacy and the persistence of invasive Avena barbata on abandoned farmland.Crossref | GoogleScholarGoogle Scholar |
Standish RJ, Cramer VA, Yates CJ (2009) A revised state-and-transition model for the restoration of eucalypt woodlands in Western Australia. In ‘New models for ecosystem dynamics and restoration’. (Eds K Suding, RJ Hobbs) pp. 169–188. (Island Press: Washington)
VSN International Ltd (2009) ‘Genstat. Release 12.1’. Available at www.vsni.co.uk [accessed December 2009].
Western Australian Herbarium (2010) ‘FloraBase – The Western Australian flora.’ (Department of Environment and Conservation). Available at http://florabase.calm.wa.gov.au/ [accessed November 2010].
Westoby M, Walker B, Noy-Meir I (1989) Opportunistic management for rangelands not at equilibrium. Journal of Range Management 42, 266–274.
| Opportunistic management for rangelands not at equilibrium.Crossref | GoogleScholarGoogle Scholar |
Yates CJ, Norton DA, Hobbs RJ (2000a) Grazing effects on plant cover, soil, and microclimate in fragmented woodlands in south-western Australia: implications for restoration. Austral Ecology 25, 36–47.
| Grazing effects on plant cover, soil, and microclimate in fragmented woodlands in south-western Australia: implications for restoration.Crossref | GoogleScholarGoogle Scholar |
Yates CJ, Hobbs RJ, Atkins L (2000b) Establishment of perennial shrub and tree species in degraded Eucalyptus salmonophloia (salmon gum) remnant woodlands: effects of restoration treatments. Restoration Ecology 8, 135–143.
| Establishment of perennial shrub and tree species in degraded Eucalyptus salmonophloia (salmon gum) remnant woodlands: effects of restoration treatments.Crossref | GoogleScholarGoogle Scholar |
