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Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems
RESEARCH ARTICLE (Open Access)

Limited evidence for the use of livestock for the conservation management of exotic plant cover

David J. Eldridge https://orcid.org/0000-0002-2191-486X A F , Ian Oliver B C , James Val D and Samantha K. Travers E
+ Author Affiliations
- Author Affiliations

A New South Wales Department of Planning, Industry and Environment, c/- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia.

B New South Wales Department of Planning, Industry and Environment, PO Box 1477, Gosford, NSW 2250, Australia.

C School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.

D New South Wales Department of Planning, Industry and Environment, PO Box 363, Buronga, NSW 2739, Australia.

E Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia.

F Corresponding author. Email: d.eldridge@unsw.edu.au

Australian Journal of Botany 68(2) 137-145 https://doi.org/10.1071/BT19183
Submitted: 25 November 2019  Accepted: 12 April 2020   Published: 6 May 2020

Journal Compilation © CSIRO 2020 Open Access CC BY-NC-ND

Abstract

Livestock grazing has been used for conservation management in some situations to reduce exotic plant cover, but supporting empirical evidence is scant. This is particularly true for eastern Australian semiarid woodlands and forests. We surveyed 451 sites across three broad semiarid vegetation communities (cypress pine, black box, red gum) in eastern Australia to examine the effects of recent and longer-term (historic) grazing by livestock on exotic (and native) plant cover. Because our focus was the use of domestic livestock for conservation management, our sites were mostly located in conservation reserves, travelling stock routes and native production forests where domestic grazing is approved via permit. We also included recent grazing by kangaroos and rabbits, which occur widely with livestock across the study sites. Structural equation modelling revealed that recent sheep and cattle grazing was associated with increased exotic plant cover in two of the three communities (cypress pine, black box), and historic grazing was associated with lower exotic (and native) plant cover across all communities. Recent cattle grazing-induced reductions in exotic plant cover in the red gum community resulted from declines in the palatable exotic annual grass Ehrharta longiflora. Higher intensity grazing by rabbits, sheep and cattle in the cypress pine community increased exotic plant cover by suppressing the negative effect of native cover on exotic cover. Higher intensity rabbit grazing reinforced the negative effect of nitrogen on native plant cover, resulting in increases in exotic cover. Overall, we found strong evidence that domestic livestock grazing reduces native plant cover either directly or indirectly in all three communities, but limited evidence that it would be a useful conservation management strategy to reduce exotic plant cover in these communities.

Additional keywords: cattle, forb, grass, herbivory, rabbit, sheep, weeds.


References

Aerts R, Berendse F (1988) The effect of increased nutrient avail- ability on vegetation dynamics in wet heathlands. Vegetatio 76, 63–69.

Bates D, Maechler M, Bolker B, Walker S (2015) Fitting linear mixed-effects models using lme4. Journal of Statistical Software 67, 1–48.
Fitting linear mixed-effects models using lme4.Crossref | GoogleScholarGoogle Scholar |

Bobbink R (1991) Effects of nutrient enrichment in Dutch chalk grassland. Journal of Applied Ecology 28, 28–41.
Effects of nutrient enrichment in Dutch chalk grassland.Crossref | GoogleScholarGoogle Scholar |

Borer ET, Seabloom EW, Gruner DS, Harpole WS, Hillebrand H, Lind EM, Adler PB, Alberti J, Anderson TM, Bakker JD, Biederman L, Blumenthal D, Brown CS, Brudvig LA, Buckley YM, Cadotte M, Chu C, Cleland EE, Crawley MJ, Daleo P, Damschen EI, Davies KF, DeCrappeo NM, Du G, Firn J, Hautier Y, Heckman RW, Hector A, HilleRisLambers J, Iribarne O, Klein JA, Knops JMH, La Pierre KJ, Leakey ADB, Li W, MacDougall AS, McCulley RL, Melbourne BA, Mitchell CE, Moore JL, Mortensen B, O’Halloran LR, Orrock JL, Pascual J, Prober SM, Pyke DA, Risch AC, Schuetz M, Smith MD, Stevens CJ, Sullivan LL, Williams RJ, Wragg PD, Wright JP, Yang LH (2014) Herbivores and nutrients control grassland plant diversity via light limitation. Nature 508, 517–520.
Herbivores and nutrients control grassland plant diversity via light limitation.Crossref | GoogleScholarGoogle Scholar | 24670649PubMed |

Bouyoucos GJ (1962) Hydrometer method improved for making particle size analysis of soils. Agronomy Journal 54, 464–465.
Hydrometer method improved for making particle size analysis of soils.Crossref | GoogleScholarGoogle Scholar |

Cardoso EJ, Vasconcellos RL, Bini D, Miyauchi MY, Santos CA, Alves PR, Paula AM, Nakatani AS, Pereira JD, Nogueira MA (2013) Soil health: looking for suitable indicators. What should be considered to assess the effects of use and management on soil health? Scientia Agricola 70, 274–289.
Soil health: looking for suitable indicators. What should be considered to assess the effects of use and management on soil health?Crossref | GoogleScholarGoogle Scholar |

Caughley G, Shepherd N, Short J (1987). ‘Kangaroos: their ecology and management in the sheep rangelands of Australia’. (Cambridge University Press: New York, USA)

Chalmers A, McIntyre S, Whalley RDB, Reid N (2005) Grassland species response to soil disturbance and nutrient enrichment on the northern tablelands of New South Wales. Australian Journal of Botany 53, 485–499.
Grassland species response to soil disturbance and nutrient enrichment on the northern tablelands of New South Wales.Crossref | GoogleScholarGoogle Scholar |

Chapman SK, Langley JA, Hart SC, Koch GW (2006) Plants actively control nitrogen cycling: uncorking the microbial bottleneck. New Phytologist 169, 27–34.
Plants actively control nitrogen cycling: uncorking the microbial bottleneck.Crossref | GoogleScholarGoogle Scholar | 16390416PubMed |

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 |

Colwell JD (1963) The optimization of the phosphorus fertilizer requirements of wheat in southern New South Wales by soil analysis. Australian Journal of Experimental Agriculture and Animal Husbandry 3, 190–197.
The optimization of the phosphorus fertilizer requirements of wheat in southern New South Wales by soil analysis.Crossref | GoogleScholarGoogle Scholar |

Cunningham GN, Mulham WE, Milthorpe PL, Leigh JH (2011). ‘Plants of Western New South Wales’. (CSIRO Publishing: Canberra).

Delgado-Baquerizo M, Maestre FT, Gallardo A, Bowker MA, Wallenstein MD, Quero JL, Ochoa V, Gozalo B, García-Gómez M, Soliveres S, García-Palacios P, Berdugo M, Valencia E, Escolar C, Arredondo T, Barraza-Zepeda C, Bran D, Carreira JA, Chaieb M, Conceição AA, Derak M, Eldridge DJ, Escudero A, Espinosa CI, Gaitán J, Gatica MG, Gómez-González S, Guzman E, Gutiérrez JR, Florentino A, Hepper E, Hernández RM, Huber-Sannwald E, Jankju M, Liu J, Mau RL, Miriti M, Monerris J, Naseri K, Noumi Z, Polo V, Prina A, Pucheta E, Ramírez E, Ramírez-Collantes DA, Romão R, Tighe M, Torres D, Torres-Díaz C, Ungar ED, Val J, Wamiti W, Wang D, Zaady E (2013) Decoupling of soil nutrient cycles as a function of aridity in global drylands. Nature 502, 672–676.
Decoupling of soil nutrient cycles as a function of aridity in global drylands.Crossref | GoogleScholarGoogle Scholar | 24172979PubMed |

Ding J, Travers SK, Delgado‐Baquerizo M, Eldridge DJ (2019) Multiple trade‐offs regulate the effects of woody plant removal on biodiversity and ecosystem functions in global rangelands. Global Change Biology 26, 709–720.
Multiple trade‐offs regulate the effects of woody plant removal on biodiversity and ecosystem functions in global rangelands.Crossref | GoogleScholarGoogle Scholar | 31518466PubMed |

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 |

Driscoll DA (2019) The Kosciuszko science accord. Ecological Management & Restoration 20, 75–76.
The Kosciuszko science accord.Crossref | GoogleScholarGoogle Scholar |

Eldridge DJ (1998) Trampling of microphytic crusts on calcareous soils, and its impact on erosion under rain-impacted flow. Catena 33, 221–239.
Trampling of microphytic crusts on calcareous soils, and its impact on erosion under rain-impacted flow.Crossref | GoogleScholarGoogle Scholar |

Eldridge DJ, Delgado-Baquerizo M (2018) Grazing reduces the capacity of landscape function analysis to predict regional-scale nutrient availability or decomposition, but not total nutrient pools. Ecological Indicators 90, 494–501.
Grazing reduces the capacity of landscape function analysis to predict regional-scale nutrient availability or decomposition, but not total nutrient pools.Crossref | GoogleScholarGoogle Scholar |

Eldridge DJ, Simpson R (2002) Rabbit Oryctolagus cuniculus L. impacts on vegetation and soils, and implications for management of wooded rangelands. Basic and Applied Ecology 3, 19–29.
Rabbit Oryctolagus cuniculus L. impacts on vegetation and soils, and implications for management of wooded rangelands.Crossref | GoogleScholarGoogle Scholar |

Eldridge DJ, Soliveres S (2014) Are shrubs really a sign of ecosystem degradation? Disentangling the myths and truths of woody encroachment in Australia. Australian Journal of Botany 62, 594–608.
Are shrubs really a sign of ecosystem degradation? Disentangling the myths and truths of woody encroachment in Australia.Crossref | GoogleScholarGoogle Scholar |

Eldridge DJ, Soliveres S, Bowker MA, Val J (2013) Grazing dampens the positive effects of shrub encroachment on ecosystem functions in a semi-arid woodland. Journal of Applied Ecology 50, 1028–1038.
Grazing dampens the positive effects of shrub encroachment on ecosystem functions in a semi-arid woodland.Crossref | GoogleScholarGoogle Scholar |

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. Ecological Applications 26, 1273–1283.
Ecosystem structure, function and composition in rangelands are negatively affected by livestock grazing.Crossref | GoogleScholarGoogle Scholar | 27509764PubMed |

Eldridge DJ, Delgado-Baquerizo M, Travers SK, Val J, Oliver I (2017) Do grazing intensity and herbivore type affect soil health? Insights from a semi-arid productivity gradient. Journal of Applied Ecology 54, 976–985.
Do grazing intensity and herbivore type affect soil health? Insights from a semi-arid productivity gradient.Crossref | GoogleScholarGoogle Scholar |

Eldridge DJ, Delgado-Baquerizo M, Travers SK, Val J, Oliver I (2018) Livestock grazing and forest structure regulate the assembly of ecological clusters within plant networks in eastern Australia. Journal of Vegetation Science 29, 788–797.
Livestock grazing and forest structure regulate the assembly of ecological clusters within plant networks in eastern Australia.Crossref | GoogleScholarGoogle Scholar |

FAO (2015) Food and Agriculture Organisation global map of aridity – 10 arc minutes. Available at http://www.fao.org/geonetwork/srv/en/ [Verified 15 September 2015]

Fensham RJ, Fairfax RJ, Ward DP (2009) Drought-induced tree death in savanna. Global Change Biology 15, 380–387.
Drought-induced tree death in savanna.Crossref | GoogleScholarGoogle Scholar |

Gilbert B, Lechowicz MJ (2005) Invasibility and abiotic gradients: the positive correlation between native and exotic plant diversity. Ecology 86, 1848–1855.
Invasibility and abiotic gradients: the positive correlation between native and exotic plant diversity.Crossref | GoogleScholarGoogle Scholar |

Golluscio RA, Austin AT, García Martínez GC, Gonzalez-Polo M, Sala OE, Jackson RB (2009) Sheep grazing decreases organic carbon and nitrogen pools in the Patagonian Steppe: combination of direct and indirect effects. Ecosystems 12, 686–697.
Sheep grazing decreases organic carbon and nitrogen pools in the Patagonian Steppe: combination of direct and indirect effects.Crossref | GoogleScholarGoogle Scholar |

Grace JB (2006) ‘Structural equation modeling and natural systems.’ (Cambridge University Press: Cambridge, UK)

Groves RH, Austin MP, Kaye PE (2003) Competition between Australian native and introduced grasses along a nutrient gradient. Austral Ecology 28, 491–498.
Competition between Australian native and introduced grasses along a nutrient gradient.Crossref | GoogleScholarGoogle Scholar |

Howard KSC, Eldridge DJ, Soliveres S (2012) Positive effects of shrubs on plant species diversity do not change along a gradient in grazing pressure in an arid shrubland. Basic and Applied Ecology 13, 159–168.
Positive effects of shrubs on plant species diversity do not change along a gradient in grazing pressure in an arid shrubland.Crossref | GoogleScholarGoogle Scholar |

Johnson CN, Jarman PJ (1987) Macropod studies at Wallaby Creek. VI: A validation of the use of dung- pellet counts for measuring absolute densities of populations of macropodids. Australian Journal of Wildlife Research 14, 139–146.
Macropod studies at Wallaby Creek. VI: A validation of the use of dung- pellet counts for measuring absolute densities of populations of macropodids.Crossref | GoogleScholarGoogle Scholar |

Keith D (2004) ‘Ocean shores to desert dunes: the native vegetation of NSW and ACT’. (NSW Office of Environment and Heritage: Sydney)

Kooijman AM, van der Meulen F (1996) Grazing as a control against ‘grass-encroachment’ in dry dune grasslands in the Netherlands. Landscape and Urban Planning 34, 323–333.
Grazing as a control against ‘grass-encroachment’ in dry dune grasslands in the Netherlands.Crossref | GoogleScholarGoogle Scholar |

Lambers H, Brundrett MC, Raven JA, Hopper SD (2010) Plant mineral nutrition in ancient landscapes: high plant species diversity on infertile soils is linked to functional diversity for nutritional strategies. Plant and Soil 334, 11–31.
Plant mineral nutrition in ancient landscapes: high plant species diversity on infertile soils is linked to functional diversity for nutritional strategies.Crossref | GoogleScholarGoogle Scholar |

Leigh JH, Wood DH, Holgate MD, Slee A, Stanger MD (1989) Effect of rabbit and kangaroo grazing on two semi- arid grassland communities in central-western New South Wales. Australian Journal of Botany 37, 375–396.
Effect of rabbit and kangaroo grazing on two semi- arid grassland communities in central-western New South Wales.Crossref | GoogleScholarGoogle Scholar |

Lezama F, Baeza S, Altesor A, Cesa A, Chaneton EJ, Paruelo JM (2013) Variation of grazing-induced vegetation changes across a large-scale productivity gradient. Journal of Vegetation Science 25, 8–21.
Variation of grazing-induced vegetation changes across a large-scale productivity gradient.Crossref | GoogleScholarGoogle Scholar |

Li S, Cadotte MW, Meiners SJ, Hua Z, Shu H, Li J, Shu W (2015) The effects of phylogenetic relatedness on invasion success and impact: deconstruction Darwin’s naturalisation conundrum. Ecological Letters 18, 1285–1292.
The effects of phylogenetic relatedness on invasion success and impact: deconstruction Darwin’s naturalisation conundrum.Crossref | GoogleScholarGoogle Scholar |

Lunt ID (2002) Grazed, burnt and, cleared: how ecologists have studied century-scale vegetation changes in Australia. Australian Journal of Botany 50, 391–407.
Grazed, burnt and, cleared: how ecologists have studied century-scale vegetation changes in Australia.Crossref | GoogleScholarGoogle Scholar |

Lunt ID, Eldridge DJ, Morgan JW, Witt GB (2007) A frame-work 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 frame-work to predict the effects of livestock grazing and grazing exclusion on conservation values in natural ecosystems in Australia.Crossref | GoogleScholarGoogle Scholar |

Maestre FT, Puche MD (2009) Indices based on surface indicators predict soil functioning in Mediterranean semi-arid steppes. Applied Soil Ecology 41, 342–350.
Indices based on surface indicators predict soil functioning in Mediterranean semi-arid steppes.Crossref | GoogleScholarGoogle Scholar |

Mellado M (2016) Dietary selection by goats and the implications for range management in the Chihuahuan Desert: a review. The Rangeland Journal 38, 331–341.
Dietary selection by goats and the implications for range management in the Chihuahuan Desert: a review.Crossref | GoogleScholarGoogle Scholar |

Myers K, Poole W (1963) A study of the biology of the wild rabbit, Oryctolagus cuniculus (L.), in confined populations IV. The effects of rabbit grazing on sown pastures. Australian Wildlife Research 2, 11–32.

Noble JC (1998) ‘The delicate and noxious scrub: CSIRO studies on native tree and shrub proliferation in the semi-arid woodlands of eastern Australia’. (CSIRO Publishing: Lyneham, Australia)

Olson BE, Lacey RJ (1994) Sheep: a method for controlling rangeland weeds. Sheep Research Journal 1994, 105–112.

Olson BE, Wallander RT (1998) Effect of sheep grazing on a leafy spurge-infested Idaho fescue community. Journal of Range Management 51, 247–252.
Effect of sheep grazing on a leafy spurge-infested Idaho fescue community.Crossref | GoogleScholarGoogle Scholar |

Page MJ, Beeton RJS (2000) Is the removal of domestic stock sufficient to restore semi-arid conservation areas? Pacific Conservation Biology 6, 245–253.
Is the removal of domestic stock sufficient to restore semi-arid conservation areas?Crossref | GoogleScholarGoogle Scholar |

Pineiro G, Paruelo JM, Oesterheld M (2006) Potential long-term impacts of livestock introduction on carbon and nitrogen cycling in grasslands of Southern South America. Global Change Biology 12, 1267–1284.
Potential long-term impacts of livestock introduction on carbon and nitrogen cycling in grasslands of Southern South America.Crossref | GoogleScholarGoogle Scholar |

Popay I, Field R (1996) Grazing animals as weed control agents. Weed Technology 10, 217–231.
Grazing animals as weed control agents.Crossref | GoogleScholarGoogle Scholar |

Pringle HJR, Landsberg J (2004) Predicting the distribution of livestock grazing pressure in rangelands. Austral Ecology 29, 31–39.
Predicting the distribution of livestock grazing pressure in rangelands.Crossref | GoogleScholarGoogle Scholar |

Prober SM, Lunt ID (2009) Restoration of Themeda australis swards suppresses soil nitrate and enhances ecological resistance to invasion by exotic annuals. Biological Invasions 11, 171–181.
Restoration of Themeda australis swards suppresses soil nitrate and enhances ecological resistance to invasion by exotic annuals.Crossref | GoogleScholarGoogle Scholar |

Prowse TAA, O’Connor PJ, Collard SJ, Rogers DJ (2019) Eating away at protected areas: Total grazing pressure is undermining public land conservation. Global Ecology and Conservation 20, e00754
Eating away at protected areas: Total grazing pressure is undermining public land conservation.Crossref | GoogleScholarGoogle Scholar |

Pywell RF, Hayes MJ, Tallowin JB, Walker KJ, Meek WR, Carvell C, Warman LA, Bullock JM (2010) Minimizing environmental impacts of grassland weed management: can Cirsium arvense be controlled without herbicides? Grass and Forage Science 65, 159–174.
Minimizing environmental impacts of grassland weed management: can Cirsium arvense be controlled without herbicides?Crossref | GoogleScholarGoogle Scholar |

Reisner MD, Grace JB, Pyke DA, Doescher PS (2013) Conditions favouring Bromus tectorum dominance of endangered sagebrush steppe ecosystems. Journal of Applied Ecology 50, 1039–1049.
Conditions favouring Bromus tectorum dominance of endangered sagebrush steppe ecosystems.Crossref | GoogleScholarGoogle Scholar |

Smit C, Ruifrok JL, van Klink R, Olff H (2015) Rewilding with large herbivores: the importance of grazing refuges for sapling establishment and wood-pasture formation. Biological Conservation 182, 134–142.
Rewilding with large herbivores: the importance of grazing refuges for sapling establishment and wood-pasture formation.Crossref | GoogleScholarGoogle Scholar |

Socher SA, Prati D, Boch S, Müller J, Baumbach H, Gockel S, Fischer M (2013) Interacting effects of fertilization, mowing and grazing on plant species diversity of 1500 grasslands in Germany differ between regions. Basic and Applied Ecology 14, 126–136.
Interacting effects of fertilization, mowing and grazing on plant species diversity of 1500 grasslands in Germany differ between regions.Crossref | GoogleScholarGoogle Scholar |

Soliveres S, Eldridge DJ, Maestre FT, Bowker MA, Tighe M, Escudero A (2011) Microhabitat amelioration and reduced competition among understorey plants as drivers of facilitation across environmental gradients: towards a unifying framework. Perspectives in Plant Ecology, Evolution and Systematics 13, 247–258.
Microhabitat amelioration and reduced competition among understorey plants as drivers of facilitation across environmental gradients: towards a unifying framework.Crossref | GoogleScholarGoogle Scholar | 25914601PubMed |

Spooner PG, Briggs SV (2008) Woodlands on farms in southern New South Wales: a longer‐term assessment of vegetation changes after fencing. Ecological Management & Restoration 9, 33–41.
Woodlands on farms in southern New South Wales: a longer‐term assessment of vegetation changes after fencing.Crossref | GoogleScholarGoogle Scholar |

Tiver F, Andrew MH (1997) Relative effects of herbivory by sheep, rabbits, goats and kangaroos on recruitment and regeneration of shrubs and trees in eastern South Australia. Journal of Applied Ecology 34, 903–914.
Relative effects of herbivory by sheep, rabbits, goats and kangaroos on recruitment and regeneration of shrubs and trees in eastern South Australia.Crossref | GoogleScholarGoogle Scholar |

Tongway D (1995) Monitoring soil productive potential. Environmental Monitoring and Assessment 37, 303–318.
Monitoring soil productive potential.Crossref | GoogleScholarGoogle Scholar | 24197857PubMed |

Travers SK, Eldridge DJ, Dorrough J, Val J, Oliver I (2018) Introduced and native herbivores have different effects on plant composition in low productivity ecosystems. Applied Vegetation Science 21, 45–54.
Introduced and native herbivores have different effects on plant composition in low productivity ecosystems.Crossref | GoogleScholarGoogle Scholar |

Travers SK, Eldridge DJ, Val J, Oliver I (2019) Rabbits and livestock grazing alter the structure and composition of mid-storey plants in a wooded dryland. Agriculture, Ecosystems & Environment 277, 53–60.
Rabbits and livestock grazing alter the structure and composition of mid-storey plants in a wooded dryland.Crossref | GoogleScholarGoogle Scholar |

van Auken OW (2009) Causes and consequences of woody plant encroachment into Western North American grasslands. Journal of Environmental Management 90, 2931–2942.
Causes and consequences of woody plant encroachment into Western North American grasslands.Crossref | GoogleScholarGoogle Scholar | 19501450PubMed |

Vandandorj S, Eldridge DJ, Travers SK, Delgado-Baquerizo M (2017) Contrasting effects of aridity and grazing intensity on multiple ecosystem functions and services in Australian woodlands. Land Degradation & Development 28, 2098–2108.
Contrasting effects of aridity and grazing intensity on multiple ecosystem functions and services in Australian woodlands.Crossref | GoogleScholarGoogle Scholar |

Yates CJ, Norton DA, Hobbs RJ (2000) 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 |