The Rangeland Journal Abstracts
The full text of the papers is available to members of The Australian Rangeland Society at http://www.publish.csiro.au/nid/202.htm
These abstracts are from the latest issue of The Rangeland Journal.
The Rangeland Journal
Vol. 39 (1)
Cattle landscape selectivity is influenced by ecological and management factors in a heterogeneous mountain rangeland
A. R. von Müller A D , D. Renison B and A. M. Cingolani C
A Instituto Nacional de Tecnología Agropecuaria Estación Experimental Agroforestal Esquel (INTA EEAf Esquel), Chacabuco 513.CP: 9200, Esquel, Chubut, Argentina.
B Instituto de Investigaciones Biológicas y Tecnológicas, Centro de Ecología y Recursos Naturales Renovables (CONICET – Universidad Nacional de Córdoba), Av. Vélez Sarsfield 1611, X5016GCA Córdoba, Argentina.
C Instituto Multidisciplinario de Biología Vegetal (CONICET – Universidad Nacional de Córdoba), Av. Vélez Sarsfield 1611, X5016GCA Córdoba, Argentina.
D Corresponding author. Email: email@example.com
The Rangeland Journal 39(1) 1-14 http://dx.doi.org/10.1071/RJ15114
Submitted: 18 November 2015 Accepted: 23 November 2016 Published: 5 January 2017
Few studies addressing drivers of cattle selectivity focus on the combination of ecological (biotic and abiotic) and management factors such as rotational systems, paddock sizes and paddock shapes. As a consequence, it is difficult to prioritise management practices integrating information of different driving factors. In a heterogeneous mountain rangeland in Central Argentina we established a total of 419 square study plots of 1 ha located in 18 paddocks with differing sizes, shapes and cattle grazing management. Plots were small samples of landscapes, covering all existing variability in vegetation and physiography. For each plot we estimated the annual cattle use, average seasonal cattle density, forage types and abiotic characteristics. We used general linear models to show that selectivity was mainly driven by biotic variables. Cattle selected landscapes dominated by short palatable plants, but the strength of this influence differed among paddocks. Selectivity was strongest in paddocks with low abundance of lawns dominated by short palatable plants and low annual stocking rate. As stocking rate and the availability of lawns increased, selectivity strength decreased. Abiotic variables had far less influence than biotic variables, showing that cattle tended to avoid rough landscapes with steep terrain in the wet-warm season; and to be attracted by permanent water sources during the dry-cold season. Seasonal stocking density and paddock size had no detectable influence on cattle selectivity and distribution. Paddock shape influenced distribution but not the strength of forage selectivity. We conclude that in our system, cattle selectivity is mainly driven by biotic factors, and the most effective methods of changing the consequent distribution pattern is by manipulating forage types and paddock shape. The role of stocking rate remains controversial as it was correlated with the proportion of lawns in the paddock.
Additional keywords: distribution patterns, domestic herbivores, grazing lawns, paddock characteristics, stocking rate.
A woody plant community and tree-cacti associations change with distance to a water source in a dry Chaco forest of Argentina
Carolina B. Trigo A B E , Andrés Tálamo A B , Mauricio M. Núñez-Regueiro C , Enrique J. Derlindati A , Gustavo A. Marás A , Alicia H. Barchuk D and Antonio Palavecino A
A Facultad de Ciencias Naturales, Universidad Nacional de Salta, Avda. Bolivia 5150, Salta, Argentina.
B Instituto de Bio y Geociencias del NOA (IBIGEO), Universidad Nacional de Salta, Consejo Nacional de Investigaciones Científicas y Técnicas, Mendoza 2, Salta, Argentina.
C School of Natural Resources and the Environment and Center for Latin American Studies, University of Florida, Gainesville, FL 32601, USA.
D Facultad de Ciencias Agropecuarias, Universidad Nacional de Córdoba, Ing Agr. Felix Aldo Marrone 746 – Ciudad Universitaria, Córdoba, Argentina.
E Corresponding author. Email: firstname.lastname@example.org
The Rangeland Journal 39(1) 15-23 http://dx.doi.org/10.1071/RJ16014
Submitted: 12 February 2016 Accepted: 21 November 2016 Published: 5 January 2017
In semiarid regions, livestock is concentrated around water sources generating a piosphere pattern (gradients of woody vegetation degradation with increasing proximity to water). Close to the water source, livestock may affect the composition, structure and regeneration strategies of woody vegetation. We used the proximity from a water source as a proxy of grazing pressure. Our objectives were (1) to compare woody vegetation attributes (richness, diversity, species composition, density and basal area) and ground cover between sites at two distances to a water source: near (higher grazing pressure) and far from the water source (lower grazing pressure), and (2) to quantify and compare cases of spatial association among the columnar cacti Stetsonia coryne (Salm-Dyck) Britton and Rose (Cactaceae), and the dominant tree Bulnesia sarmientoi Lorentz ex Griseb. (Zygophyllaceae). We used a paired design with eight pairs of rectangular plots distributed along a large and representative natural water source. We found lower total species richness, plant density and soil cover near than far from water source, and more cases of spatial associations between the two species studied. Our results show evidence of increased livestock impacts around water sources. However, we found no difference in terms of species composition or basal area at near versus far sites. We conclude that grazing pressure might be changing some attributes of the woody plant community, and that the association of young trees with thorny plants (grazing refuge) could be a regeneration mechanism in this semiarid forest with high grazing pressure.
Additional keywords: grazing pressure, regeneration, water resource.
Exploring relationships between native vertebrate biodiversity and grazing land condition
Scott A. Parsons A , Alex Kutt B , Eric P. Vanderduys C , Justin J. Perry C and Lin Schwarzkopf A D
A Centre for Tropical Biodiversity and Climate Change, College of Science and Engineering, James Cook University, Townsville, Qld 4811, Australia.
B Bush Heritage Australia, Level 1, 395 Collins St, Melbourne, Vic. 3000, Australia.
C CSIRO Land and Water, Townsville, Qld 4811, Australia.
D Corresponding author. Email: email@example.com
The Rangeland Journal 39(1) 25-37 http://dx.doi.org/10.1071/RJ16049
Submitted: 26 May 2016 Accepted: 4 January 2017 Published: 3 February 2017
Although commercial grazing can degrade natural habitats, sustainably grazed land may be effective for wildlife conservation. Thus, land condition frameworks that assess the landscape quality of grazed land may also be useful for assessment of habitat quality for wildlife. However, the relationship between the condition of grazed land and native biodiversity is mostly unknown, and this knowledge gap must be addressed to adequately balance commercial production and conservation. In the present case study we determined the relevance of a widely used grazing land condition scale to understanding native vertebrate species richness and abundance (birds, reptiles, amphibians, mammals and all these vertebrate classes grouped) in grazed rangelands in northern Australia (~24–13°S; annual rainfall ranging from >1200 to <400 mm), sampled over approximately 10 years from 17 unique sites, containing 381 1-ha study plots. We defined the land condition scale relative to climate and comprehensive assessment of habitat attributes, and then described the relationships between land condition, habitat and biodiversity. The land condition scale partially explained richness and abundance patterns only for mammals (especially rodents), which tended to be higher in better-condition pasture. For other vertebrate groups, the scale was a very poor descriptor of richness and abundance. The land condition scale was not useful to assess wildlife diversity primarily because ‘woody thickening’ (increases in woody vegetation on grazed land, including shrubs and trees) lowers the ‘grazing value’ of land while also generally promoting vertebrate diversity. In line with this, biodiversity decreased with increasing bare ground and erosion, together with, and in the absence of, vegetation cover (i.e. desertification), consistent with grazing land degradation. The present study supports observations that land clearing and reductions in woody vegetation on grazed rangelands are particularly detrimental to native vertebrates.
Additional keywords: biodiversity conservation, grasslands, land condition index, land management, rangeland ecology, savanna woodlands.
Effectiveness of best practice management guides for improving invasive species management: a review
Michael J. Coleman A C , Brian M. Sindel B and Richard A. Stayner A
A Institute for Rural Futures, School of Behavioural, Cognitive and Social Sciences, University of New England, Armidale, NSW 2351, Australia.
B Agronomy and Soil Science, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.
C Corresponding author. Email: firstname.lastname@example.org
The Rangeland Journal 39(1) 39-48 http://dx.doi.org/10.1071/RJ16087
Submitted: 25 August 2016 Accepted: 9 December 2016 Published: 9 January 2017
Best practice management (BPM) guides are a key component of invasive species extension in Australia, and are becoming a more important way of reaching land managers with comprehensive invasive species management strategies. However, little is known about the quantifiable benefits of these guides as a stand-alone extension approach, or in comparison with other approaches. We therefore reviewed the existing literature to determine when this form of extension was appropriate, what determines the success or failure of BPM guides in facilitating best practice invasive species management, how effective they had been in the Australian context, and what methods were available to evaluate BPM guide effectiveness. BPM guides are most appropriately used in support of other forms of extension and enforcement of invasive species regulations; as a cost-effective alternative to more labour-intensive extension techniques; or in bringing together disparate information in a single comprehensive source for land managers and extension practitioners. They appear to be most appropriately distributed at mid- and late-stages of the invasion curve. Limited quantitative evidence of the effectiveness of BPM guides for invasive species in Australia is available, although there is a consensus that these materials are popular among target audiences, despite a range of studies having shown face-to-face extension to be more effective. Unfortunately, many factors make successful evaluation of a BPM guide difficult, such that extension professionals are less likely to consider the possibility of evaluation. However, we argue that extension professionals need to consider evaluation of written BPM guides, where time and funding makes this possible. Ideally this will involve formative evaluation to improve the content and messages of the guide, as well as summative evaluation to determine its effectiveness among the target audience and for the target species. We also suggest a range of economic evaluation possibilities that warrant further exploration and trial.
Additional keywords: agricultural extension, feral animal species, land manager education, pest management, weed species.
Assessment of the potential of a range of microhabitats for use as seed production areas in moderately degraded rangelands in semiarid Australia
Judith M. Bean A B D , Gavin J. Melville A and Ronald B. Hacker A C
A Trangie Agricultural Research Centre, PMB 19, Trangie, NSW 2823, Australia.
B Present address: PO Box 578, Gunnedah, NSW 2380, Australia.
C Present address: Tenambit, NSW 2323, Australia.
D Corresponding author. Email: email@example.com
The Rangeland Journal 39(1) 49-58 http://dx.doi.org/10.1071/RJ16095
Submitted: 13 September 2016 Accepted: 19 December 2016 Published: 27 January 2017
Previous studies in mulga country with hard-setting red earth soils in north-west New South Wales, Australia, have demonstrated that small fenced seed production areas on local high points can contribute to regeneration of native perennial vegetation, and increases in the soil seedbank, on surrounding slopes. In this study the potential of seven microhabitats in this environment, each replicated twice, for use as seed production areas was assessed indirectly by a study of their functional characteristics and vegetation dynamics. Indices of landscape function (stability, infiltration and nutrient cycling) were determined for each of the 14 sites at the time of fencing and at the end of the study, over 2 years later, by determining the extent and surface characteristics of 53 surface types (in total) along three parallel transects within each site. Variation in establishment and survival of ground storey species among surface types was examined by co-ordination of all plants within belts centred on the line transects. At the start of the study landscape function indices for the ‘rocky ridge with rock outcrop’ microhabitat were not significantly higher than all, or some, other microhabitats. By the end of the study two of the three indices for this microhabitat were significantly higher than for all other microhabitats. This microhabitat also favoured the establishment and survival of the pastorally preferred species Monachather paradoxus Steud and Thyridolepis mitchelliana (Nees) S.T. Blake but did not favour establishment and survival of the pastorally unpreferred species Aristida jerichoensis (Domin) Henrad and Austrostipa variabilis (Hughes) S.W.L. Jacobs and J. Everett. This microhabitat was characterised by extensive areas of ‘water catchment’ surface types associated with in-situ rock outcrop, which facilitated the observed vegetation dynamics. This ‘rocky ridge with rock outcrop’ microhabitat occurs on local high points in the landscape and is readily recognised. It is therefore ideally suited for use as fenced seed production areas to assist rangeland regeneration.
Additional keywords: establishment, landscape function, rangeland regeneration, survival.
Managing competitive interactions to promote regeneration of native perennial grasses in semi-arid south-eastern Australia
Ronald B. Hacker A B C , Ian D. Toole A , Gavin J. Melville A , Yohannes Alemseged A and Warren J. Smith A
A NSW Department of Primary Industries, Trangie Agricultural Research Centre, Trangie, NSW 2823, Australia.
B Present address: Tenambit, NSW 2323, Australia.
C Corresponding author. Email: firstname.lastname@example.org
The Rangeland Journal 39(1) 59-71 http://dx.doi.org/10.1071/RJ16048
Submitted: 22 May 2016 Accepted: 29 December 2016 Published: 20 January 2017
Treatments to reduce available soil nitrogen and achieve specified levels of weed control were evaluated for their capacity to promote regeneration of native perennial grasses in a degraded semi-arid woodland in central-western New South Wales. Treatments were factorial combinations of nitrogen-reduction levels and weed-control levels. The four levels of nitrogen reduction were no intervention, and oversowing of an unfertilised summer crop, an unfertilised winter crop or an unfertilised perennial grass. The three weed-control levels were defined by the outcome sought rather than the chemical applied and were nil, control of annual legumes and control of all annual species (AA).
Regeneration of perennial grasses, predominantly Enteropogon acicularis, was promoted most rapidly by the AA level of weed control with no introduction of sown species. Sown species negated the benefits of weed control and limited but did not prevent the regeneration of native perennials. Sown species also contributed substantially to biomass production, which was otherwise severely limited under the AA level of weed control, and they were effective in reducing soil nitrogen availability. Sown species in combination with appropriate herbicide use can therefore maintain or increase available forage in the short–medium term, permit a low rate of native perennial grass recruitment, and condition the system (by reducing soil mineral nitrogen) for more rapid regeneration of native perennials should annual sowings be discontinued or a sown grass fail to persist.
Soil nitrate was reduced roughly in proportion to biomass production. High levels of soil nitrate did not inhibit native perennial grass regeneration when biomass was suppressed by AA weed control, and may be beneficial for pastoral production, but could also render sites more susceptible to future invasion of exotic annuals. The need for astute grazing management of the restored grassland is thus emphasised. This study was conducted on a site that supported a remnant population of perennial grasses. Use of the nitrogen-reduction techniques described may not be appropriate on sites where very few perennial grass plants remain.
Additional keywords: pasture cropping, soil fertility.
Monitoring of plant phenology and seed production identifies two distinct seed collection seasons in the Australian arid zone
Alison L. Ritchie A B C D , Todd E. Erickson A B and David J. Merritt A B
A School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, WA 6009, Australia.
B Kings Park and Botanic Garden, Kings Park, WA 6005, Australia.
C Department of Environment and Agriculture, Curtin University, Bentley, WA 6102, Australia.
D Corresponding author. Email: email@example.com
The Rangeland Journal 39(1) 73-83 http://dx.doi.org/10.1071/RJ16050
Submitted: 26 May 2016 Accepted: 28 November 2016 Published: 5 January 2017
Phenological patterns including peak flowering and seed production of 19 grass, herb, shrub and tree species were studied in the Pilbara biogeographic region of Western Australia. Each plant population was monitored monthly over an 18-month period. Qualitative data was collected capturing plant phenophases. Plant fecundity was estimated using X-ray analyses to determine the proportion of seeds produced. Two main phenological patterns were established across plant life-forms. Precipitation during the summer wet season provided sufficient soil moisture for grasses to emerge from a dormant vegetative state and rapidly transition into flowering and seed production. In contrast, the deeper-rooted shrubs and herbs commenced flowering before the onset of the summer rains, completing their reproductive cycle before the period of higher moisture availability. The patterns observed indicated that the different plant life-forms co-existing within the Pilbara differentially exploit the available resources of this arid region. The contrasting phenological patterns between plant life-forms across seasons likely represent adaptations to a competitive, arid environment where water is the limiting resource. To meet the increasing demand for native seeds of diverse plant species for ecosystem restoration, plant phenological data will become increasingly important for deriving seed supply strategies from wild or managed plant populations.
Additional keywords: drylands, flowering, reproductive biology, restoration, seed ecology, seed yield.
Assessing the invasion threat of non-native plant species in protected areas using Herbarium specimen and ecological survey data. A case study in two rangeland bioregions in Queensland
Michael R. Ngugi A B and Victor John Neldner A
A Queensland Herbarium, Department of Science Information Technology and Innovation, Mt Coot-tha Road, Toowong, Qld 4066, Australia.
B Corresponding author. Email: Michael.firstname.lastname@example.org
The Rangeland Journal 39(1) 85-95 http://dx.doi.org/10.1071/RJ16076
Submitted: 8 August 2016 Accepted: 18 November 2016 Published: 28 December 2016
Naturalised non-native plants that become invasive pose a significant threat to the conservation of biodiversity in protected areas (areas dedicated and managed for long-term conservation of nature), economic productivity of agricultural businesses, and societal impacts including community, culture infrastructure and health. Quantifying the spread, potential dominance and invasion threat of these species is fundamental to effective eradication and development of threat mitigation policy. But this is often hampered by the lack of comprehensive data. This study used existing ecological survey data from 2548 sites and 64 758 Herbarium specimen records to document the status and abundance of non-native plants in two case study bioregions, Cape York Peninsula (CYP) and the Desert Uplands (DEU) in Queensland covering a total area of 186 697 km2. There were 406 non-native species in the CYP, 186 (45.6%) of which are known environmental weeds and 159 non-natives in DEU, of which 69 (43.5%) are environmental weeds. Inside the protected areas, there were 98 species of environmental weeds in CYP, 27 of which are listed as weeds of State significance (Weeds of National Significance (WONS), Queensland declared and non-declared pest plants categories). In DEU, there were 18 environmental weeds inside protected areas and none of them was listed as a weed of State significance. Non-native species that recorded foliage cover dominance in the ecological site data are generally recognised as environmental weeds in Queensland. The threat of weeds from outside of protected areas was serious, with 41 weeds of State significance found in CYP, five of which are WONS, and 25 weeds of State significance found in DEU, 10 of which are WONS.
Additional keywords: alien plants, declared weeds, environmental weeds, invasive species, naturalised species.
Dynamics of grazing rights and their impact on mobile cattle herders in Bhutan
Kuenga Namgay A C , Joanne E. Millar B and Rosemary S. Black B
A Ministry of Agriculture and Forests, Bhutan; and Charles Sturt University, Albury, NSW 2640, Australia.
B School of Environmental Sciences, Charles Sturt University, PO Box 789, Albury, NSW 2640, Australia.
C Corresponding author. Email: email@example.com
The Rangeland Journal 39(1) 97-104 http://dx.doi.org/10.1071/RJ16052
Submitted: 31 May 2016 Accepted: 4 January 2017 Published: 27 January 2017
Seasonal cattle movements have been an important part of the living cultural heritage in Bhutan for centuries. Herders migrate south every winter to graze their cattle on subtropical pastures and to work in orange orchards. They return north to their villages in spring to grow summer crops. However, the practice of transhumant agropastoralism is under increasing pressure on account of changes in land-use policies, climate change and a declining labour force as youth seek alternative livelihoods. This research investigated the impact of changes in land-use policy, with emphasis on the Land Act 2007, on current and future livelihoods of transhumant herders in Bhutan. During in-depth interviews with 24 transhumant herders and nine livestock advisors, and seven focus-group discussions with 64 participants including herders, downstream residents and development agency personnel, perspectives on this issue were gathered. Findings revealed a lack of herder awareness of changes in land-use policies and minimal consultation of herders during policy development. Confusion and uncertainty about the proposed redistribution of grazing rights and restrictions on herd movements have resulted in confusion and resentment and have created conflicts between upstream and downstream communities. Herders with no current alternatives are concerned about their future livelihoods, whereas others are leaving it to their children to decide their future. It is concluded that the motive behind nationalisation of rangeland is noble and timely, but there are flaws in the redistribution plan. Transhumant agropastoralism is already in decline and there is no need to push towards its end through legislation. Transhumant practices could be left to evolve towards what may be their natural end. Sudden stoppage of inter-district transhumance without offering meaningful alternatives to herders could result in negative environmental and socioeconomic impacts. In future, policy development needs to increasingly embrace science and be based on evidence. A genuine participatory process with citizen engagement could avoid the unintended negative impacts likely to be faced by transhumant herders with marginal land holdings, who depend on this production system for their livelihoods.
Additional keywords: land law, land use, mobility, pastoralism, transhumance, rangeland.