To see the other types of publications on this topic, follow the link: Temperate native pasture.
Journal articles on the topic 'Temperate native pasture'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Temperate native pasture.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Pearson, C. J., R. Brown, W. J. Collins, K. A. Archer, M. S. Wood, C. Petersen, and B. Bootle. "An Australian temperate pastures database." Australian Journal of Agricultural Research 48, no. 4 (1997): 453. http://dx.doi.org/10.1071/a96095.
Full textAbstract:
A census of pasture types and their composition and attributes (e.g. purpose and carrying capacity) was carried out throughout southern Australia from June to October 1994. This paper describes the survey process and subsequent creation of an Australian temperate pastures database. Data were created for 562 local government areas (LGAs) from ‘desk estimates’ by trained agriculturists. They identified about 2500 pasture types, which were grouped into 120 standardised pasture categories. Some findings from the data are identified, namely the high relative importance on an area basis of unimproved native pastures, the importance of weedy species (e.g. Vulpia), and the marked decline with increasing rainfall in importance of annual medics compared with subterranean clover. This paper provides examples of the data and their use for assessment of the regional economic impact of increases in productivity of pasture species.
2
Vere, D. T., R. E. Jones, and M. H. Campbell. "The economics of temperate pasture systems on the central and southern Tablelands of New South Wales." Rangeland Journal 23, no. 2 (2001): 159. http://dx.doi.org/10.1071/rj01003.
Full textAbstract:
Pastures are the basis of most forms of agricultural production on the New South Wales central and southern tablelands. Pastures occupy the bulk of the region's landmass and pasture-based livestock production annually contributes more than three-quarters of the regional gross value of rural production. Throughout the region, there is substantial variation in pasture composition, ranging from high quality introduced perennial grasses and legumes to pastures comprising mainly low quality native species. This paper examines the economics of the main categories of temperate pastures over a range of soil fertility-rainfall environments on the south-eastern tablelands areas of New South Wales. Using a linear programming model and discounted development budgets, the results demonstrate the strong influence of the environment on the economics of the individual pasture systems. The highest economic returns in both the short and longer-terms were to the introduced perennial grass pastures in most of the environments. Pastures based on introduced legumes and the high quality native species also generated sound economic returns, although there are recognised problems with the persistence of the legume pastures. Over time, the returns to the better quality native pastures compare favourably with the introduced legumes and are better suited to acidic soils than the perennial grasses. Low quality native species produced relatively poor economic returns in all environments and unfortunately, are the main pasture type in the region's less favourable environments.
3
Eyles, Alieta, Garth Coghlan, Marcus Hardie, Mark Hovenden, and Kerry Bridle. "Soil carbon sequestration in cool-temperate dryland pastures: mechanisms and management options." Soil Research 53, no. 4 (2015): 349. http://dx.doi.org/10.1071/sr14062.
Full textAbstract:
Permanent pastures, which include sown, native and naturalised pastures, account for 4.3 Mha (56%) of the national land use in Australia. Given their extent, pastures are of great interest with respect to their potential to influence national carbon (C) budgets and CO2 mitigation. Increasing soil organic C (SOC) mitigates greenhouse gases while providing other benefits such as pasture productivity, soil health and ecosystem services. Several management approaches have been recommended to increase C sequestration in pasture-based systems; however, results have proved variable and often contradictory between sites and years. Here, we present an overview of the processes and mechanisms responsible for C sequestration in permanent pastures. In addition, we discuss the merits of traditional and emerging pasture-management practices for increasing SOC in pastures, with a focus on dryland pasture systems of south-eastern Australia. We conclude by summarising the knowledge gaps and research priorities for soil C-sequestration research in dryland pastures. Our review confirms that soils under a range of pasture types have considerable potential for sequestration of atmospheric CO2 in Australia, and that the magnitude of this potential can be greatly modified by pasture-management practices. Although the shortage of long-term studies under Australian conditions limits our ability to predict the potential of various management approaches to sequester soil C, our review indicates that prevention of erosion through maintenance of groundcover and adoption of options that promote deep C sequestration are likely to confer broad-scale maintenance or increases in SOC in pasture soils over a decade or longer. We acknowledge that the evidence is limited; therefore, confidence in the recommended practices in different locations and climates is largely unknown.
4
Lodge, G. M. "Studies of soil seedbanks in native and sown pastures in northern New South Wales." Rangeland Journal 23, no. 2 (2001): 204. http://dx.doi.org/10.1071/rj01007.
Full textAbstract:
Total and germinable soil seedbanks (litter and soil) were studied for a native pasture and three sown pastures (dominated by Phalaris aquatica L. cv. Sirosa) in northern New South Wales from 1993 to 1996. Soil core samples were taken from continuously grazed plots for both pasture types and two oversown treatments in the native pasture and from a spring-autumn rest treatment at the sown pasture sites. At each site above ground herbage mass was also estimated regularly as part of the Temperate Pasture Sustainability Key Program. For all sites and treatments, the proportion of germinable seeds as a percentage of the total (dormant and germinable) seedbank ranged from 1–26% for the native pasture and 1–39% for the sown pastures. Germinable seed numbers ranged from 280 to 26,110 seeds per m2, while total seedbank numbers were from 6700 to 178,360 seeds per m2. Native pasture herbage mass was dominated by native perennial grasses, but seeds of these species were less than 20% of the total seed bank in all treatments in 1994 and 1995. At the sown pasture sites, most of the germinable (51–92%) and total (65–97%) seedbanks were either barnyard grass (Echinochloa crus-galli (L.) Beauv, annual ryegrass (Lolium rigidum Gaudin), subterranean clover (Trifolium subterraneum L.) or wireweed (Polygonum aviculare L.). Since seeds of annuals and other forbs generally dominated both the total and germinable seedbanks of these perennial grass-based pastures, these species were likely to increase over time. Seeds of the sown perennial grass Phalaris aquatica L, cv. Sirosa were less than 1% of the total seedbanks in pastures sown in 1990 and less than 3% of those sown in 1979. With above average summer rainfall at the native pasture site in 1996 and prolific growth of redgrass, seeds of this species were 38–63% of the total and 11–29% of the germinable seedbank in May 1996. Except at this site and time, the species composition of the total and germinable seedbanks did not generally reflect the dominance of the above ground herbage mass of these pastures by perennial grasses.
5
Barnes, Phoebe, Brian R. Wilson, Mark G. Trotter, David W. Lamb, Nick Reid, Terry Koen, and Leopold Bayerlein. "The patterns of grazed pasture associated with scattered trees across an Australian temperate landscape: an investigation of pasture quantity and quality." Rangeland Journal 33, no. 2 (2011): 121. http://dx.doi.org/10.1071/rj10068.
Full textAbstract:
Scattered paddock trees occur across agricultural landscapes in Australia. However, in the temperate regions of Australia their numbers are rapidly declining and they may be lost across much of the landscape in 200 years. Here we examined the spatial distribution of green (GDB), senescent (SDB) and total (TDB) dry pasture biomass, and nutrient status of the GDB fraction around scattered Eucalyptus trees on three parent materials (basalt, granite and meta-sediment) in native and sown pastures across a range of grazed temperate landscapes in northern New South Wales. We used a combination of destructive harvests and a handheld active optical canopy reflectance sensor (AOS) with an integrated GPS to examine pasture biomass around scattered trees. The harvested pasture biomass data indicated that under grazed conditions the presence of scattered trees did not introduce significant radial trends in TDB or GDB out to a distance of 3.5 canopy radii regardless of tree species or parent material. The red and near-infrared reflectance-based Normalised Difference Vegetation Index (NDVI), as measured by the AOS, did indicate a consistent azimuthal trend with larger GDB on the southern side of the tree and lower GDB on the northern side in the native pasture. However, this observation must be qualified as the regression coefficient for the relationship between NDVI and GDB was significant but weak (best r2 = 0.42), and SDB reduced its predictive capacity. We also found a higher percentage of GDB under the canopy than in the open paddock. We suggest that the combination of these results may indicate higher grazing pressure under trees than in the open paddock. Pasture nutrient concentration (P, K and S) was higher in both native and sown pastures beneath the tree canopy compared with the open paddock. This study indicates that, in this temperate environment, scattered trees do not adversely affect pasture production, and that they can improve some pasture nutrients.
6
Vickery, P. J., M. J. Hill, and G. E. Donald. "Satellite derived maps of pasture growth status: association of classification with botanical composition." Australian Journal of Experimental Agriculture 37, no. 5 (1997): 547. http://dx.doi.org/10.1071/ea97014.
Full textAbstract:
Summary. Spectral data from the green, red and near-infrared bands of Landsat MSS and Landsat TM satellite imagery acquired in mid-spring were classified into 3 and 6 pasture growth classes respectively. The classifications were compared with a site database of botanical composition for the Northern Tablelands of New South Wales to examine the association between spectral growth class and pasture composition. Pastures ranged in composition from unimproved native perennial grasses through semi-improved mixtures of native and naturalised grasses and legumes to highly improved temperate perennial grasses and legumes. For 3 years of MSS data, the fast growth class had a mean botanical composition of about 80% improved perennial grass and 0% native; medium growth class averaged 46% improved perennial grass and 14% native; while the slow growth class had about 60% native and 1% improved perennial grass when averaged over 3 years of MSS data. For the 6 class TM data from a single year, a predictive logistic regression of cumulative probability was developed for percentage of ‘very fast’ growth pixels and ordered 10 percentile categories of improved perennial grass or native grass. Differences in patch characteristics between classes with MSS disappeared with TM reclassified to the same 3 class level. Most probable pasture type was inferred from 3 class MSS and TM data using Bayesian probability analysis. The resulting maps were similar in general appearance but detail was better with the TM data. The pasture growth classification identified highly improved perennial grass pastures and native pastures but sensitivity to intermediate pasture types was poor. Future improvement will come from direct measurement of biophysical characteristics using vegetation indices or inversion of reflectance models.
7
Garden, D. L., G. M. Lodge, D. A. Friend, P. M. Dowling, and B. A. Orchard. "Effects of grazing management on botanical composition of native grass-based pastures in temperate south-east Australia." Australian Journal of Experimental Agriculture 40, no. 2 (2000): 225. http://dx.doi.org/10.1071/ea98010.
Full textAbstract:
Grazing management strategies to alter botanical composition of native pastures were investigated at 4 locations in the high rainfall zone of south-east Australia, including Tasmania. These studies were conducted as part of the Temperate Pasture Sustainability Key Program, which evaluated the effects of grazing management on a wide range of pasture types between 1993 and 1996. Pastures in this study were based on Aristida ramosa/Bothriochloa macra, Microlaena stipoides–Austrodanthonia spp. or Themeda triandra–Austrodanthonia spp. Seasonal rests, increased grazing pressure in spring, mob stocking and cutting for hay were compared to continuous grazing at all sites. In addition, specific local treatments were tested at individual sites. Changes in composition resulting from the treatments were minimal at most sites. This may have been due to a combination of the inherent stability of the pastures, the relatively short duration of the experiments, and the drought conditions experienced, which minimised differences between treatments. Some strategies to alter composition of natural pastures are suggested. In the Aristida–Bothriochloa pasture there was a general decrease in Aristida and an increase in Bothriochloa, which was largely unaffected by the type of grazing management applied. The combination of drought conditions and increasing grazing pressure was sufficient to alter composition without specific management strategies being necessary. In the Themeda–Austrodanthonia pasture, resting in spring, 12-month rests or cutting for hay (which involved a spring rest) allowed Themeda to increase in the pasture. The Microlaena–Austrodanthonia pastures were very stable, especially where annual grass content was low. However, certain treatments allowed Microlaena to increase, a result which is regarded as being favourable. The major effects in these latter pastures were on undesirable species. Vulpia spp. were reduced by resting in autumn and increased spring grazing pressure, while Holcus lanatus was increased dramatically by resting in spring and was also increased by resting in autumn or winter, but only when conditions were suitable for growth of this species. In many cases, treatment differences were only expressed following recovery from drought, showing that timing of grazing management to achieve change is critical.
8
Vere, D. T., R. E. Jones, and M. H. Campbell. "Long-term change in the economic productivity of four major pasture categories on the south-eastern Tablelands of New South Wales." Rangeland Journal 23, no. 2 (2001): 148. http://dx.doi.org/10.1071/rj01002.
Full textAbstract:
The perception of change or decline in the productivity of temperate pastures in south-eastern Australia is an important concern to livestock producers and pasture scientists. Much of this concern relates to reductions in the proportions of desirable species in the composition of pasture systems as a result of increased soil and weed problems. The purpose of this paper is to investigate trends in the long-term economic productivity of four categories of temperate pastures (all introduced pastures, introduced perennial grasses, introduced legumes and all native pastures) on the central and southern tablelands of New South Wales. The results provide evidence of economic productivity decline in the all introduced pastures category in relation to sheep production, but this has been due to productivity decline in the dominant legume component of the introduced pastures. In contrast, there has been strong growth in the economic productivity of the introduced perennial grass pastures. Abnormally high beef cattle numbers in the mid-1970s appear to have created an illusion of high productivity and subsequent decline in all introduced pastures. In contrast, the economic productivity of the native pastures which are the bulk of the region's grazing areas, has fallen substantially.
9
Whalley, R. D. B., D. A. Friend, P. Sanford, and M. L. Mitchell. "Evaluation of native and introduced grasses for low-input pastures in temperate Australia: rationale and scope." Rangeland Journal 27, no. 1 (2005): 1. http://dx.doi.org/10.1071/rj05004.
Full textAbstract:
The historical approach to pasture improvement in the high rainfall zone of temperate Australia has been to add introduced herbaceous legumes and to replace perennial native grasses with introduced species requiring high inputs of fertiliser for maintenance. The application of this high-input approach on land with low capability has lead to the loss of perennial grasses, erosion, soil acidification and increasing salinity on the lower slopes. This model of pasture improvement has not been successful on the margins of the wheat belt and in semi-arid regions. The Native and Low-input Grasses Network (NLIGN) was established in 1996 to coordinate research on grasses suitable for land with low capability and for semi-arid regions. The NLIGN multi-site evaluation project was initiated to test promising lines (accessions) of native and introduced grasses for low-input pastures at eight sites across southern Australia. The broad objective of the project was to identify native and/or introduced perennial grass lines that had possible commercial potential for low-input pastures. This objective was achieved in an initial 3-year evaluation phase, which began in 1998 and tested lines for persistence, production and palatability.
10
King, K. L., and K. J. Hutchinson. "Pasture and grazing land: assessment of sustainability using invertebrate bioindicators." Australian Journal of Experimental Agriculture 47, no. 4 (2007): 392. http://dx.doi.org/10.1071/ea05270.
Full textAbstract:
Impacts of practices frequently used to manage Australian pastures are reviewed with the aim of determining which groups are responsive to changes in grazing regime, fertiliser use, pasture types, tree clearing, pesticide use, liming and irrigation. Invertebrate groups sensitive to pasture management regimes may be potential candidates for use as bioindicators of ecological sustainability of these pasture types. This review concentrates on the more intensively utilised temperate pastures of southern Australia, as very little work has been done on the impact of the grazing animal and pasture management on invertebrate fauna on the extensive rangelands of the arid and semiarid zones. Background to the relative importance of invertebrates in the functioning of the pasture ecosystem is given. This has culminated in the construction of food webs for two temperate perennial pastures (an unfertilised, native and a fertilised, sown pasture) at Armidale, NSW, for which there is comprehensive data available. Invertebrate bioindicators of pasture sustainability emerged from the consideration of grazing lands and invertebrate responses. Currently, only four groups would seem to be likely candidates as bioindicators of sustainability of pastures. These are soil nematodes, earthworms, protozoa and Collembola. The main difficulty in monitoring these groups is that it requires specialist expertise, and services provided by commercial laboratories for routine biological soil tests are still in their infancy. There are gaps in our knowledge of how invertebrate fauna react to the pressing issues of soil acidity and salinity.
11
Badgery, W. B., and D. L. Michalk. "Synthesis of system outcomes for a grazing-management experiment in temperate native pastures." Animal Production Science 57, no. 9 (2017): 1869. http://dx.doi.org/10.1071/an16599.
Full textAbstract:
Increasing the intensity of grazing management from continuous grazing or set-stocking to intensive rotational grazing has been proposed as a way of improving the profitability and environmental outcomes for native pasture-based grazing systems in the high-rainfall zone (HRZ) of southern Australia. The present paper synthesised the results and outcomes of eight papers covering different aspects of a grazing-system study investigating the intensity of grazing management at Panuara (33°27ʹS, 148°56ʹE), 25 km south-west of Orange, New South Wales. The systems analysis covered soils and soil water, pastures, animal production, profitability and business risk by using a combination of field experiments and biophysical modelling. The experimental approach, engagement with stakeholders and the potential impact of the research outcomes are discussed; as are the future directions for grazing system research. Increasing the intensity of grazing management from a 1- to a 20-paddock system resulted in a 21% higher pasture growth, 22% higher stocking rate and 20% higher lamb production per hectare. However, modelling demonstrated that seasonal variability had a greater impact on profitability than did the management system, and whole-farm profitability of the 20-paddock system was lower than that of the 1- and 4-paddock systems due to higher infrastructure costs. Pasture stability was associated with a high perennial grass content (>70%), and a stocking rate of 4.2 ewes/ha for continuous grazing or 5.3 ewes/ha for intensive rotational grazing limited the potential for degradation events. Advantages were identified in fencing and managing production zones, with different production potential within a farm, to improve utilisation across the landscape and efficiency of fertiliser use. The farming-system approach successfully integrated field research with pre- and post-experimental modelling, and with strategic input from an advisory group containing farmers, researchers and advisors, to develop a full understanding of the impact, at a system level, of increasing the intensity of grazing management in the HRZ.
12
Boschma, S. P., G. M. Lodge, and S. Harden. "Establishment and persistence of perennial grass and herb cultivars and lines in a recharge area, North-West Slopes, New South Wales." Crop and Pasture Science 60, no. 8 (2009): 753. http://dx.doi.org/10.1071/cp08357.
Full textAbstract:
Two adjacent sites, one previously cropped and the other a native pasture, were sown with perennial temperate and tropical grasses and herbs (Expt 1), Phalaris aquatica (phalaris) and Festuca arundinacea (tall fescue) cultivars or lines (Expt 2), and perennial tropical grasses (Expt 3) near Manilla, NSW. Establishment, herbage mass and plant frequency were assessed in 2003–06 to (i) identify cultivars/lines with superior persistence, (ii) detect possible mechanisms required for successful production and persistence in a summer-dominant rainfall environment, and (iii) examine the comparative performance of the species groups when sown into previously cropped and native pasture areas. Plots were fertilised annually and grazed or mown at least seasonally. Most cultivars/lines persisted at the previously cropped site, while those on the native pasture site had to be resown and generally failed to persist beyond the first year. At the previously cropped site, summer-dormant tall fescue cv. Resolute MaxP® was the most persistent of the grasses evaluated in Expt 1. Grasses such as Lolium perenne cv. Avalon and Bromus stamineus cv. Gala did not perenneate, but regenerated annually from seed. Native grasses generally had poor establishment; however, Austrodanthonia richardsonii and A. fulva tended to increase in plant frequency over time. Chloris gayana (Rhodes grass) cv. Katambora and Panicum maximum (panic) cv. Gatton were the only tropical grasses that established in Expt 1, and both had plant frequencies similar (P > 0.05) to the temperate grasses at the final assessment. In Expt 2, Resolute MaxP again was the most persistent cultivar/line. Several experimental lines of phalaris (e.g. T39 and M225) had high herbage mass and good persistence compared with commercial cultivars. In Expt 3, Katambora Rhodes grass and Digitaria eriantha ssp. eriantha (digit grass) cv. Premier were the most persistent cultivars and had the highest herbage mass. These data highlighted summer dormancy in temperate grasses and frost tolerance in tropical grasses as two possible mechanisms important for persistence of grasses on the North-West Slopes of NSW and the risks associated with sowing perennial grasses into established native pastures.
13
Pyle, Lysandra A., Linda M. Hall, and Edward W. Bork. "Soil properties in northern temperate pastures do not vary with management practices and are independent of rangeland health." Canadian Journal of Soil Science 99, no. 4 (December 1, 2019): 495–507. http://dx.doi.org/10.1139/cjss-2019-0076.
Full textAbstract:
Studies examining the influence of disturbance and management history on pasture soils across a large sampling area are uncommon. We report on the soil properties found in 102 northern temperate pastures sampled in central Alberta, Canada, and relate these attributes to ongoing pasture management practices compiled from producer surveys and aboveground measures of rangeland health (RH). Tame pastures, typically seeded to introduced forages, were associated with higher soil fertility (total carbon, nitrogen, and organic matter) than semi-native grasslands, which were associated with coarse-textured soils. Soil properties remained independent of most grazing and pasture management practices, including the grazing systems, class of livestock, fertilization, and stocking rate. However, manure application, often combined with harrowing, was associated with improved soil fertility and increased electrical conductivity (salinity). Soils with a fire history reported by land managers, largely in the Boreal natural region, were characterized by a greater soil C:N ratio. Soil surface properties (litter cover, litter depth, and bare soil) were responsive to grazing management, with growing season and year-round grazing associated with a thinner litter layer having less cover, and bare ground twice as high under continuous grazing compared with pastures rotationally grazed. Further, variation in soil surface cover was associated with contrasting RH classes (healthy, healthy with problems, and unhealthy), whereas soil attributes remained unrelated to RH. This study demonstrates that soils within these northern temperate grasslands are relatively insensitive to many pasture management practices, and highlights that existing RH assessments may provide limited insight into differences in mineral soil properties.
14
Murphy, S. R., and G. M. Lodge. "Ground cover in temperate native perennial grass pastures. I. A comparison of four estimation methods." Rangeland Journal 24, no. 2 (2002): 288. http://dx.doi.org/10.1071/rj02016.
Full textAbstract:
Studies were conducted to compare visual estimates of ground cover and canopy cover by both inexperienced and experienced observers and to compare those estimates with those from more objective methods in native pastures in the high rainfall, temperate rangelands of northern NSW. Ground cover and canopy cover of 60 quadrats was estimated using visual, mapped area, digital image analysis and photo point quadrat methods. Inexperienced observers were trained by estimating ground cover of reference quadrats. Differences between mean visual estimates of ground cover and canopy cover for experienced and inexperienced observers were not significant (P>0.05). Mean ground cover estimates by the mapped area, digital image analysis and point quadrat methods were also not different from each other. The overall relationship between mean visual estimate and mean objective estimate of ground cover was non-linear (second order polynomial, R2 = 0.93), observers tending to underestimate in the mid-range (20 to 80%) of cover compared with objective methods. Mean visual estimate of ground cover was 73.7% compared with the mean objective estimate of 83.7%. Visual estimates of canopy cover (mean 34.6%) were highly correlated (R2 = 0.90) with those of the mapped area method (mean 34.3%) and the relationship was linear. Measurement of ground cover is a standard technique used in many pasture ecology and management studies and is increasingly being used by land managers to monitor pasture production and sustainability. Inexperienced observers were trained quickly and easily to estimate ground cover and canopy cover with sufficient accuracy to identify ranges of cover using visual estimation, indicating that the visual estimation technique should be suitable for estimating ground cover in land management research.
15
Michalk, D. L., W. B. Badgery, and D. R. Kemp. "Balancing animal, pasture and environmental outcomes in grazing management experiments." Animal Production Science 57, no. 9 (2017): 1775. http://dx.doi.org/10.1071/an16132.
Full textAbstract:
About 60% of the gross value of Australia’s agriculture (AU$49 billion) is produced from the 85 million ha of temperate grasslands of southern Australia. A large part of this production comes from grazing livestock in the high-rainfall zone (HRZ) where 40% of the area has been retained as native and naturalised pastures, located in variable landscapes. These native pastures have seen a decline in productivity and increasing environmental problems, such as erosion, due to a loss of productive perennial species over recent decades. Grazing management systems have been advocated to not only balance the quality and quantity of forage with the nutritional demands of grazing animals, but also to manage the degradation caused by grazing. There has been an evolution of grazing management research through national projects from Temperate Pasture Sustainability Key Program to Sustainable Grazing Systems and then EverGraze, which has shifted from a focus on small plots and fixed stocking rates, to large-plot and farmlet experiments that include landscape variability and flexible grazing systems that more closely resemble commercial practice. These experiments generate reliable plant and animal response data that can be used to validate system models needed to assess the spatial and temporal challenges of grassland management. The present paper introduces the research conducted at the Orange proof site as part of the national EverGraze program. The research investigated the interactions between landscape variability and grazing method (1-, 4- and 20-paddock grazing management treatments) with flexible stocking rates. The following three key questions were addressed: (1) does increasing the number of paddocks and implementing rotational grazing result in a higher stocking rate, higher per hectare production and better economic outcomes; (2) which is the most appropriate combination of grazing method and stocking rate to achieve a higher and more stable perennial component to improve production and environmental benefits in different parts of the landscape; and (3) can landscape variability be identified, mapped and effectively managed on HRZ native grassland properties? This special edition of Animal Production Science answers these questions and provides recommendations for managing HRZ native pastures.
16
Bowen, M. K., D. P. Poppi, and S. R. McLennan. "Efficiency of rumen microbial protein synthesis in cattle grazing tropical pastures as estimated by a novel technique." Animal Production Science 57, no. 8 (2017): 1702. http://dx.doi.org/10.1071/an15535.
Full textAbstract:
The efficiency of microbial protein synthesis (EMPS) in cattle grazing a range of tropical pasture types was examined using a new method of intra-jugular infusion of chromium–EDTA to estimate urinary excretion of purine derivatives. Seven pasture types were studied in south-eastern Queensland, Australia, over a 13-month period. These included native tropical grass (C4) pasture (major species Heteropogon contortus and Bothriochloa bladhii) studied in the early wet, the wet–dry transition and the dry season; introduced tropical grass (C4) pasture (Bothriochloa insculpta) in the mid-wet season; two introduced tropical legume species (C3; Lablab purpureus and Clitoria ternatea); and the temperate-grass (C3) pasture, ryegrass (Lolium multiflorum). There was a large range in EMPS across pasture types, with a range of 26–209 g microbial crude protein per kilogram digestible organic matter intake (DOMI). Estimated rumen-degradable protein (RDP) supply (42–525 g/kg DOMI) was the major factor associated with EMPS across the range of pasture types studied. EMPS in steers grazing all tropical grass pastures was low (<130 g/kg DOMI) and limited by RDP supply. Negative linear relationships (P < 0.05) between EMPS and concentrations of both neutral detergent fibre and acid detergent fibre in extrusa were evident. However, non-fibre carbohydrate in extrusa, total non-structural carbohydrate concentration in plucked pasture leaf, rumen fluid and particle dilution rate, protozoal concentration in rumen fluid and rumen fluid pH were not correlated with EMPS. It was concluded that EMPS was well below 130 g microbial crude protein per kilogram DOMI when cattle grazed unfertilised, tropical grass pastures in south-eastern Queensland and that RDP was the primary limiting nutrient. High EMPS was associated with a very high RDP, vastly in excess of RDP requirements by microbes.
17
Sanford, P., R. D. B. Whalley, D. L. Garden, M. R. Norton, C. M. Waters, A. B. Smith, M. L. Mitchell, et al. "Identification of superior native and introduced grasses for low-input pastures in temperate Australia." Rangeland Journal 27, no. 1 (2005): 55. http://dx.doi.org/10.1071/rj05005.
Full textAbstract:
This paper is the fifth in a series describing trials evaluating native and introduced grasses at eight locations across temperate Australia. In these trials, 62 perennial grass lines were assessed for herbage production, survival and recruitment under low fertiliser conditions using spaced plants produced in glass houses and transplanted into the field. Sites were grouped into three different climatic zones: Eastern Australian permanent pasture, Eastern Australian mixed farming and Mediterranean zone. For each of these zones, superior lines were identified and their potential use in permanent pastures or mixed farming discussed. Among the C3 grasses tested, several lines of Dactylis glomerata from France on the Mediterranean coast near the Spanish border and from north-west maritime France proved to be superior lines in all zones and were better than the standard comparator cv. Currie with regard to the attributes assessed. In general, the D. glomerata lines were superior to the C3 native species except with respect to survival and recruitment. The C4 introduced standard comparator Eragrostis curvula cv. Consol was outstanding with regard to its herbage production and survival in all climatic zones, although its recruitment was generally low. Native C4 lines of Themeda australis and Paspalidium jubiflorum yielded well in all climatic zones, and even produced more herbage than Consol in one zone. Survival rates of T. australis and P. jubiflorum were also very high but recruitment was low under the conditions of the trial. In mixed pastures C4 grasses may reduce fluctuations in feed supply as well as increase water use. As a consequence mixtures of superior C3 and C4 lines identified in this study are likely to be suitable for pastures on infertile soils and in zones subjected to continuous or periodic drought. Further work on the behaviour of these superior lines under sward conditions in association with forage legumes and their responses to grazing is needed; however, for the promising native lines, sward trials are not possible until suitable technology for commercial seed production and broad acre establishment of these lines has been developed.
18
Moore, G. A., P. Sanford, P. J. Dolling, and D. Real. "The challenges of developing resilient perennial pastures for a Mediterranean environment – a review for Western Australia." Crop and Pasture Science 72, no. 9 (2021): 613. http://dx.doi.org/10.1071/cp20304.
Full textAbstract:
Perennial pastures are the dominant feedbase in many regions of the world, and offer several advantages when compared with an annual pasture system. In Western Australia (WA) there has been a concerted effort over seven decades to develop new perennial pasture options and expand the adoption of suitable species. The agricultural region of WA (i.e. south-western Australia) is characterised by a Mediterranean climate where the 5–7 month summer drought has proved a considerable challenge with only a small number of the many promising species being adopted commercially. Research, development, and extension have covered a wide range of herbaceous perennial legumes, leguminous and native shrubs, herbs, and temperate and warm season grasses. This paper reviews the literature to determine whether a perennial pasture must satisfy the following criteria to be successful and widely adopted in south-western Australia: (i) sourced from a similar Mediterranean environment and adapted to the target soils; (ii) have a relative advantage over the annual-based system it replaces; (iii) a robust management package; and (iv) a viable seed supply. The findings of this review highlight that perennial pastures must indeed satisfy multiple criteria to be commercially successful. Notably, the requirement for the source of the germplasm to have a good match between climate and soils is less clear because some of the commercially successful species come from diverse environments. We conclude with some key learnings for future perennial pasture development as climate change intensifies the research challenge and the drive for producers to adapt.
19
Cullen, B. R., R. J. Eckard, and R. P. Rawnsley. "Resistance of pasture production to projected climate changes in south-eastern Australia." Crop and Pasture Science 63, no. 1 (2012): 77. http://dx.doi.org/10.1071/cp11274.
Full textAbstract:
Climate change impact analysis relies largely on down-scaling climate projections to develop daily time-step, future climate scenarios for use in agricultural systems models. This process of climate down-scaling is complicated by differences in projections from greenhouse gas emission pathways and, in particular, the wide variation between global climate model outputs. In this study, a sensitivity analysis was used to test the resistance of pasture production to the incremental changes in climate predicted over the next 60 years in southern Australia. Twenty-five future climate scenarios were developed by scaling the historical climate by increments of 0, 1, 2, 3 and 4°C (with corresponding changes to atmospheric carbon dioxide concentrations and relative humidity) and rainfall by +10, 0, –10, –20 and –30%. The resistance of annual and seasonal pasture production to these climatic changes was simulated at six sites in south-eastern Australia. The sites spanned a range of climates from high rainfall, cool temperate in north-west Tasmania to the lower rainfall, temperate environment of Wagga Wagga in southern New South Wales. Local soil and pasture types were simulated at each site using the Sustainable Grazing Systems Pasture model. Little change or higher annual pasture production was simulated at all sites with 1°C warming, but varying responses were observed with further warming. In a pasture containing a C4 native grass at Wagga Wagga, annual pasture production increased with further warming, while production was stable or declined in pasture types based on C3 species in temperate environments. In a cool temperate region pasture production increased with up to 2°C warming. Compared with the historical baseline climate, warmer and drier climate scenarios led to lower pasture production, with summer and autumn growth being most affected, although there was some variation between sites. At all sites winter production was increased under all warming scenarios. Inter-annual variation in pasture production, expressed as the coefficient of variation, increased in the lower rainfall scenarios where production was simulated to decline, suggesting that changing rainfall patterns are likely to affect the variability in pasture production more than increasing temperatures. Together the results indicate that annual pasture production is resistant to climatic changes of up to 2°C warming. The approach used in this study can be used to test the sensitivity of agricultural production to climatic changes; however, it does not incorporate changes in seasonal and extreme climatic events that may also have significant impacts on these systems. Nonetheless, the approach can be used to identify strategies that may increase resilience of agricultural systems to climate change such as the incorporation of C4 species into the pasture base.
20
HUTCHINSON, K. J., and K. L. KING. "Volume and activity of micro-organisms in litter from native and sown temperate pasture species." Austral Ecology 14, no. 2 (June 1989): 157–67. http://dx.doi.org/10.1111/j.1442-9993.1989.tb01424.x.
Full text
21
Bowen, M. K., D. P. Poppi, and S. R. McLennan. "Ruminal protein degradability of a range of tropical pastures." Australian Journal of Experimental Agriculture 48, no. 7 (2008): 806. http://dx.doi.org/10.1071/ea07414.
Full textAbstract:
The rumen degradability parameters of the diet selected by two to four oesophageal-fistulated Brahman steers grazing a range of tropical pastures were determined by incubation of extrusa in nylon bags suspended in the rumen of rumen-fistulated (RF) Brahman steers. The effective protein degradability (Edg) was determined by measuring the rate of disappearance of neutral detergent insoluble nitrogen (NDIN) less acid detergent insoluble nitrogen (ADIN) in the incubated extrusa. Six to eight RF steers also grazed each of the pastures along with the oesophageal-fistulated steers, to allow determination of key rumen parameters and rumen particulate matter fractional outflow rates (FOR). The seven pastures studied included: native tropical grass (C4) pasture (major species Heteropogon contortus and Bothriochloa bladhii), studied in the early wet (NPEW), the wet/dry transition (NPT) and the dry (NPD) seasons; introduced tropical grass (C4) pasture (Bothriochloa insculpta), studied in the mid wet season (BB); the introduced tropical legumes (C3), Lablab purpureus (LL) and Clitoria ternatea (BP); and the temperate grass (C3) pasture, ryegrass (Lolium multiflorum, RG). Using the measured particle FOR values in calculations, the Edg estimates were very high for both C4 and C3 species: 0.82–0.91 and 0.95–0.98 g/g crude protein (CP), respectively. Substitution of an assumed FOR (kp = 0.02/h) for the measured values for each pasture type did not markedly affect estimates of Edg. However, C4 tropical grasses had much lower effective rumen degradable protein (ERDP) fractions (23–66 g/kg DM) than the C3 pasture species RG and LL (356 and 243 g/kg DM, respectively). This was associated with a lower potential degradability and degradation rate of organic matter (OM) in sacco, lower in vitro organic matter digestibility (IVOMD) and CP concentrations in the extrusa, and lower ammonia-N and branched-chain fatty acid concentrations in rumen fluid for the tropical grasses. As tropical grass pastures senesced, there was a decline in Edg, the ERDP and rumen undegradable protein (UDP) fractions, the potential degradability and degradation rate of OM and the IVOMD. These results provide useful data for estimating protein supply to cattle grazing tropical pastures.
22
Hall, E. J., S. J. Hughes, A. W. Humphries, and R. Corkrey. "Habitat and plant diversity of Trifolium tumens (Steven ex M. Bieb.) collected in Azerbaijan and its characterisation and field evaluation in Tasmania, Australia." Crop and Pasture Science 64, no. 4 (2013): 374. http://dx.doi.org/10.1071/cp13040.
Full textAbstract:
Trifolium tumens (Talish clover) is a perennial legume species not previously domesticated for use in world agriculture. It is native to areas of the eastern Mediterranean, Caucasus and mountainous areas of the Middle East with a warm temperate or cool Mediterranean environment. The species has been identified by pasture researchers in Australia as a having sufficient drought and grazing tolerance to fill a gap created by the lack of a well adapted perennial legume for dryland pasture systems across low rainfall (450 to 750 mm annual average rainfall), temperate regions of Australia. The need to expand available genetic diversity of this species resulted in a germplasm collecting mission to Azerbaijan in 2004. The successful mission collected seed from 35 populations of T. tumens across 7 agro ecological zones, including 5 climatic zones. This collection increased the number of accessions held in ex situ local and international collections from 21 to 56. The range of adaptation and frequency of the collection of T. tumens was far greater than expected with accessions found at altitudes ranging from 12 to 1700 m above sea level, in soils with pH (1:5 H20) ranging between 5.0 and 9.0 and rainfall varying from 300 to 1300 mm. T. tumens was found growing alongside a diverse range of companion species in heavily grazed lowland pastures up to lightly grazed alpine meadows. This material has been characterised by the Tasmanian Institute of Agriculture (TIA), with promising accessions contributing to a breeding program to develop a commercial cultivar adapted to temperate environments (<750 mm rainfall).
23
Jones, R. E., P. M. Dowling, D. L. Michalk, and W. McG King. "Sustainable grazing systems for the Central Tablelands of New South Wales. 5. A bioeconomic framework for assessing the long-term economic benefits of grazing management tactics and implications for sustainability." Australian Journal of Experimental Agriculture 46, no. 4 (2006): 495. http://dx.doi.org/10.1071/ea04196.
Full textAbstract:
There have been significant declines in the perennial grass (PG) content in native and sown pastures across temperate Australia. Not only has this reduced agricultural productivity, it has contributed to more serious degradation, such as loss of soil and biodiversity, decreasing water quality, and dryland salinity caused by rising watertables. Results from the Sustainable Grazing Systems Key Program (SGS) research undertaken at Carcoar on the Central Tablelands of New South Wales were reported by Michalk et al. (2003). This research indicated that grazing management tactics can be used to manipulate pasture composition, thereby changing animal production and water-use patterns. The main grazing tactic investigated was termed a summer grazing rest, where resting was imposed in late spring if PG composition was <50%. Reported in this present paper is an economic framework for valuing the long-term benefits of grazing management tactics. The framework involves the development of a bioeconomic modelling system that links a dynamic programming model with biophysical models for water and environmental processes, soil fertility, pasture growth, livestock energy requirements and the change in pasture species composition. The study concludes that long-term economic returns are improved by strategies, e.g. a summer rest, that lead to an increase in PG composition over time. The study also determined that environmental factors, such as deep drainage, runoff and soil loss, are reduced as perenniality is increased.
24
Martínez-Falcón, Ana Paola, Gustavo A. Zurita, Ilse J. Ortega-Martínez, and Claudia E. Moreno. "Populations and assemblages living on the edge: dung beetles responses to forests-pasture ecotones." PeerJ 6 (December 13, 2018): e6148. http://dx.doi.org/10.7717/peerj.6148.
Full textAbstract:
Edge effects alter insect biodiversity in several ways. However, we still have a limited understanding on simultaneous responses of ecological populations and assemblages to ecotones, especially in human modified landscapes. We analyze edge effects on dung beetle populations and assemblages between livestock pastures and native temperate forests (Juniperusand pine-oak forests (POFs)) to describe how species abundances and assemblage parameters respond to edge effects through gradients in forest-pasture ecotones. InJuniperusforest 13 species avoided the ecotones: six species showed greater abundance in forest interior and seven in pasturelands, while the other two species had a neutral response to the edge. In a different way, in POF we found five species avoiding the edge (four with greater abundance in pastures and only one in forest), two species had a neutral response, and two showed a unimodal pattern of abundance near to the edge. At the assemblage level edge effects are masked, as species richness, diversity, functional richness, functional evenness, and compositional incidence dissimilarity did not vary along forest-pasture ecotones. However, total abundance and functional divergence showed higher values in pastures in one of the two sampling localities. Also, assemblage similarity based on species’ abundance showed a peak near to the edge in POF. We propose that conservation efforts in human-managed landscapes should focus on mitigating current and delayed edge effects. Ecotone management will be crucial in livestock dominated landscapes to conserve regional biodiversity and the environmental services carried out by dung beetles.
25
McCaskill, M. R., M. L. Mitchell, R. Zollinger, R. D. Armstrong, and D. Partington. "Dry matter and nutritive value responses of native, naturalised and sown pasture species to soil Olsen P." Crop and Pasture Science 70, no. 12 (2019): 1097. http://dx.doi.org/10.1071/cp18544.
Full textAbstract:
The soil phosphorus (P) requirements of 18 species that included native grasses and naturalised legumes were compared with the predominant sown species (Trifolium subterraneum, Lolium perenne and Phalaris aquatica) in a series of glasshouse and field experiments based on the Long-term Phosphate Experiment at Hamilton, Victoria. The native grasses Austrostipa scabra and Rytidosperma caespitosum had the lowest external P requirements, as measured by the Olsen P at which 90% of maximal dry matter (DM) production was obtained, but were of low nutrient value as livestock feed. The naturalised legume Lotus corniculatus had the lowest external P requirement of the legumes, but had low DM production. The highest legume DM production under low-P conditions in the field and one glasshouse experiment was obtained for T. subterraneum. This was attributed to its large seed, which enables rapid initial growth and thus captures light and nutrient resources early in the growing season. However, it forms a relatively low proportion of the pasture sward in low-P soil under grazed mixed pasture conditions in the field. This was attributed to its relatively high nutritive value, which leads to it being preferentially grazed, leaving species that are either less palatable or less accessible to grazing livestock. This work suggests that, in low-P environments, there is a much stronger selection pressure favouring low relative palatability over P efficiency. In conclusion, to maintain desirable species in temperate low-input pastures, sufficient P needs to be applied to maintain fertility above a threshold at which the less-palatable species begin to invade.
26
Waters, C. M., D. L. Garden, A. B. Smith, D. A. Friend, P. Sanford, and G. C. Auricht. "Performance of native and introduced grasses for low-input pastures. 1. Survival and recruitment." Rangeland Journal 27, no. 1 (2005): 23. http://dx.doi.org/10.1071/rj05001.
Full textAbstract:
Differential survival and recruitment patterns are commonly ignored within plant selection and breeding programs, where attention is focused largely on selection of cultivars with high biomass and seed yields. However, in low-input situations, where fertiliser application is limited, the use of pasture species with superior survival and recruitment characteristics can offer the potential of cost-effective pasture establishment. We investigated the comparative survival and seedling recruitment of 62 native and introduced perennial grasses under low-fertility conditions within three agro-ecological zones of temperate Australia: the temperate high-rainfall pasture zone; drier mixed-farming areas and Mediterranean southern Australia. Plants were grown from seed in glasshouses and transplanted to the field as spaced plants within 6–8 weeks. At regular intervals, survival of transplanted plants and recruitment of new plants were recorded. We found high mortality over a relatively short (24-month) period among both native and introduced grasses, despite good establishment. Frost damage at the cooler sites resulted in death of some C4 plants early in the experiment. Survival of some lines declined following the dry summer of 2000–01, and lines with best survival after this time were Eragrostis curvula cv. Consol, Austrodanthonia fulva (from Dalgety and Wagga, NSW) and Paspalidium jubiflorum (from Warren, NSW). C3 grasses, which generally had poor survival were a Microlaena stipoides selection from Nile, Tasmania, and two lines of Elymus scaber (Boorowa and Tumut, NSW). The C4 grasses Chloris truncata (Girilambone, NSW) and Dichanthium sericeum (Trangie, NSW) also exhibited poor survival, although there were exceptions at some sites. The native lines A. caespitosa Tas2407, M. stipoides cv. Shannon and A. racemosa were the most successful recruiters. Introduced lines generally had lower recruitment, although two lines of D. glomerata from Spain recruited well at some sites. C4 lines generally had poor recruitment, including E. curvula cv. Consol, Bothriochloa macra, Themeda australis, Enteropogon acicularis, D. sericeum, P. jubiflorum and P. constrictum. The role of plants adapted to low-input situations is discussed, as well as the implications of the attributes of survival and recruitment for selection of new cultivars for these situations.
27
Smith, R. W., C. A. Harris, K. Cox, D. McClements, S. G. Clark, Z. Hossain, and A. W. Humphries. "A history of Australian pasture genetic resource collections." Crop and Pasture Science 72, no. 9 (2021): 591. http://dx.doi.org/10.1071/cp20336.
Full textAbstract:
The introduction of exotic pasture germplasm has formed the foundation of many Australian grazing systems. Scientists have searched the world for plants to improve the feedbase, amassing collections of diverse genetic material, creating genebanks that have made a large contribution to feedbase productivity. These genebanks contain a vast range of legumes, grasses, herbs and shrubs with growth habits ranging from small herbaceous plants to woody trees and life cycles from annuals to short- and long-term perennial plants. They have been collected from cool temperate to tropical climates and arid to high-rainfall zones. Hundreds of cultivars have been developed from material either collected by Australian plant breeders overseas or introduced from overseas genebanks. The collection of this germplasm has enabled plant breeders to extend the area of adaptation of species into climates, soils and systems previously considered marginal. The importance to Australian and world agriculture is increasing as plant breeders seek traits to meet the challenges of a changing climate and animal production systems. Furthermore, urbanisation, landscape degradation and political instability are making it increasingly difficult to collect pasture and forage germplasm from native grasslands in many countries. This emphasises the need to maintain and improve the capacity of the Australian Pastures Genebank (APG). The APG houses ~85000 accessions and is a modern, online source of diversity for plant scientists around the world. This paper summarises the history of the founding genebank collections, their environment and farming systems focus, and the visionary and resourceful individuals that built them.
28
Dear, B. S., G. A. Moore, and S. J. Hughes. "Adaptation and potential contribution of temperate perennial legumes to the southern Australian wheatbelt: a review." Australian Journal of Experimental Agriculture 43, no. 1 (2003): 1. http://dx.doi.org/10.1071/ea01202.
Full textAbstract:
Deep-rooted perennial pasture plants can play an important role in solving the environmental problems of rising watertables, dryland salinity and soil acidification in the wheatbelt of southern Australia. These problems are attributed to the extensive clearing of perennial native vegetation and its replacement with shallow-rooted winter-growing annual crops and pastures. Deep-rooted, herbaceous perennial legumes, particularly lucerne (Medicago sativa L.), are seen as making an increasing contribution in the cropping zones where high rates of symbiotic nitrogen fixation and increased water use are high priorities. This paper reviews the current use and the potential of a range of temperate perennial legumes for the wheatbelt of southern Australia. The genera examined include Medicago, Hedysarum, Trifolium, Onobrychis, Lotus, Galega, Astragalus, Lathyrus, Anthyllis, Psoralea, Dorycnium, Lespedeza and Securigera. There is considerable scope to expand the use of lucerne; however, there is also a need for alternative perennial species to increase biodiversity and to fill niches where lucerne is less suited. Based on current knowledge, the species with the most promise to complement lucerne include sainfoin (Onobrychis viciifolia Scop.) and sulla (Hedysarum coronarium L.) on alkaline soils, strawberry clover (Trifolium fragiferum L.) in wet or mildly saline niches and Lotus and Dorycnium spp. on waterlogged and/or acid soils.
29
Oram, Rex, and Greg Lodge. "Trends in temperate Australian grass breeding and selection." Australian Journal of Agricultural Research 54, no. 3 (2003): 211. http://dx.doi.org/10.1071/ar02137.
Full textAbstract:
Current trends in grass cultivar development are reviewed, with respect to the range of species involved, and the objectives and methodology within each species. Extrapolations and predictions are made about future directions and methodologies. It is assumed that selection will necessarily cater for the following environmental changes: (1) higher year-round temperatures, higher variability of rainfall incidence, and lower total winter and spring rainfall along the south of the continent; (2) higher nutrient and lime inputs as land utilisation intensifies; and (3) the grazing management requirements of the important pasture components will be increasingly defined and met in practice.The 'big four' species, perennial ryegrass, phalaris, cocksfoot and tall fescue, will continue to be the most widely sown species in temperate regions for many decades, with the latter 3 increasing most in area and genetic differentiation. However, species diversification will continue, especially with native grasses, legumes, and shrubs from fertile regions of Australia and exotics from little-explored parts of the world, such as South Africa, western North and South America, coastal Caucasus, and Iraq–Iran. By contrast, the recent high rate of species diversification in the tropics and subtropics will probably give way to a much lower rate of cultivar development by refinement and diversification within the established species. Domestication of native grasses will continue for amenity, recreational, land protection, and grazing purposes. As seed harvesting technologies and ecological knowledge improve, natural stands will become increasingly important as local sources of seed. It is suggested that many native grasses have been greatly changed by natural selection so as to withstand strong competition from introduced species under conditions of higher soil fertility and grazing pressure. Conversely, some introduced species are being selected consciously and naturally to persist in regions with irregular rainfall and less fertile soils. Therefore, the distinction between native and introduced grasses may be disappearing, and many populations of native species could now be as foreign to the habitats of pre-European settlement as are populations of introduced species that have been evolving here for 50–200 years. Methods used for genetic improvement will continue to be selection among both overseas accessions and the many native and introduced populations that have responded to natural selection in Australia. As well, there will be deliberate recurrent crossing and selection programs in both native and introduced species for specific purposes and environments. Increasingly, molecular biology methods will complement traditional ones, at first by the provision of DNA markers to assist the selection of complex traits, and for proving distinctness to obtain Plant Breeders' Rights for new cultivars. Later, genetic engineering will be used to manipulate nutritive value, resistance to fungal and viral diseases, and breeding systems, especially cytoplasmic male sterility and apomixis, to utilise heterosis in hybrid cultivars of grasses, particularly for dairying and intensive meat production.Areas where the practice and management of grass breeding and selection programs could be improved are highlighted throughout the review, and reiterated in a concluding statement. Most problems appear to stem from inadequate training in population ecology, population genetics, evolution, and quantitative inheritance.
30
Amidy, Martin R., Karl Behrendt, and Warwick B. Badgery. "Assessing the profitability of native pasture grazing systems: a stochastic whole-farm modelling approach." Animal Production Science 57, no. 9 (2017): 1859. http://dx.doi.org/10.1071/an16678.
Full textAbstract:
Grazing enterprises on the Central Tablelands of New South Wales employ a range of different strategies to manage temperate native grassland pastures common in the high rainfall zone of southern Australia. This paper uses a stochastic whole-farm simulation modelling approach to assess the impact of grazing system and stocking rate (SR) on the long-term profitability of a representative case-study enterprise. In particular, the impact of infrastructure costs, debt and downside risk, on whole-farm performance are examined over a 10-year planning horizon. In total, 12 different strategies were modelled under both price and climate risk, with a matrix of three paddock systems (1-paddock, 4-paddock and 20-paddock rotations) and four stocking rates (SR of 3, 4.2, 5.3 and 7 ewes/ha). Profitability was primarily driven by SR. In general, higher SR increased total farm output and annual profits under favourable conditions, although they were also associated with higher costs and greater downside risk in poor seasons, which in turn was magnified by the compounding effect of accumulating debt over time. When SR increased above 4.2 ewes/ha, it had a negative impact on lamb sale weights, resulting in lower prices due to lambs not meeting the ≥40-kg liveweight specification. Although this was offset by increased whole-farm production volumes at 5.3 ewes/ha, declines in profitability occurred at 7 ewes/ha as a result of significant increases in supplement feeding costs, and lambs not meeting sale weight specifications. The analytical scale of the analysis also had an impact on the relative profitability between alternative treatments. When assessed using a partial measure of economic analysis (gross margin per ha), there was little difference between paddock system treatments at the same SR. When the cost of additional fencing and water infrastructure were accounted for at the whole-farm analytical scale, the 20 paddock system was markedly less profitable than the 1- and 4-paddock rotations. This highlights the need for assessing production systems at an appropriate analytical and temporal scale to better understand the relationship between the key drivers of long-term profitability and risk. Overall there were relatively small differences in whole-farm performance between the four best performing strategies in this study. Given the trade-offs between profitability, downside risk, ground cover and feedbase sustainability, the lower risk 1- and 4-paddock systems with a SR of 4.2 ewes/ha are proposed as being optimal.
31
Cropper, Mark, Xesús García, Gonzalo Flores, and Jaime Zea. "Lamb Production from Grass in Galicia (North-West Spain): The Effect of Pasture Height and Creep Feeding on Ewe and Lamb Performance." Proceedings of the British Society of Animal Production (1972) 1994 (March 1994): 54. http://dx.doi.org/10.1017/s0308229600026052.
Full textAbstract:
Unlike most of Spain, Galicia's temperate, humid climate supports year-round grass growth, with a moderate summer drought. Local lamb markets demand lean, light carcases (10-12kg) produced from lambs grazing whilst still with the ewe. Grazing systems studies with the native Gallego breed, Flores (1992) established optimum grazing heights as 8.0 cm for individual lamb liveweight gain (LWG) and 5.5 cm for LWG/hectare but no data were recorded on the carcase yield. The objective of this trial was to test whether optimum individual LWG and carcase yield is obtained under these systems.
32
Real, D., C. A. Labandera, and J. G. Howieson. "Performance of temperate and subtropical forage legumes when over-seeding native pastures in the basaltic region of Uruguay." Australian Journal of Experimental Agriculture 45, no. 3 (2005): 279. http://dx.doi.org/10.1071/ea03131.
Full textAbstract:
In 1997, an integrated plant breeding program was initiated at the National Agricultural Research Institute (INIA) Uruguay, to develop forage legumes and root nodule bacteria which were able to be productive in co-existence with the native (grass-dominant) vegetation when grazed by cattle and sheep. The program was conducted in parallel with rhizobial strain selection by the Rhizobium–Biological Nitrogen Fixation Unit of the Soil Microbiology Department of the Ministry of Livestock, Agriculture and Fisheries of Uruguay and the Centre for Rhizobium Studies (CRS), Murdoch University, Western Australia. Between 1998 and 2000, 326 temperate and subtropical forage legume species originating from 38 ex-situ seed collections were evaluated in 3 plantings on: red lithosol, black lithosol and vertisol soils at Glencoe Research Station in Uruguay. Row–column field designs were used. Forage production at the end of the second year of evaluation was used as the key selection parameter for the introduced legumes because their success required persistence in the pasture either vegetatively or by natural reseeding. This study identified a set of promising legumes and strains of Rhizobium that are now available for further study and breeding in Uruguay as well as other countries with a similar climate. The methodology developed in this study may be applicable to forage selection programs in which competition between annual and perennial species is expected to influence outcomes.
33
Johnston, W. H., C. A. Clifton, I. A. Cole, T. B. Koen, M. L. Mitchell, and D. B. Waterhouse. "Low input grasses useful in limiting environments (LIGULE)." Australian Journal of Agricultural Research 50, no. 1 (1999): 29. http://dx.doi.org/10.1071/a97159.
Full textAbstract:
This paper presents a case for the selection and development of a wider range of perennial grasses for pastoral use in the higher rainfall (annual rainfall >500 mm) zone of southern Australia, especially the southern sector of the Murray–Darling Basin. There is also a need to reconsider the use of ‘high-input’ pastures on hill lands by developing more appropriate recommendations for managing existing native grass pastures productively. Past experiments which compared native grass based pastures with sown pastures promoted the view that indigenous grasses were inferior in most respects to exotic improved species. Even though many of the findings were confounded with fertiliser, stocking rate, and other treatment effects, they reinforced the general direction of cultivar development programs which in the temperate zone have been based mainly on the 4 exotic C3 species Phalaris aquatica L., Dactylis glomerata L., Lolium L. spp., and Festuca elatior var. arundinacea (Schreb.) Hackel (syn. Festuca arundinacea Schreb). This has led to an imbalance in the adaptability and range of species available to be sown in pastures, particularly for sowing on less productive landscapes where stony, shallow, infertile, acid soils limit the persistence of current cultivars. The pre-European vegetation of temperate Australia comprised species with a capacity for active growth and transpiration during summer. The water use pattern resulted in soil moisture being near capacity in late winter and spring, and exhausted by summer’s end. Replacement of this vegetation with annual-growing and summer-dormant C3 species has changed the water use pattern so that soils are drier in spring and wetter in autumn. This has reduced the pre-winter soil moisture deficit, which in turn has increased rates of deep drainage in winter. Land degradation in southern Australia is a consequence of this changed water use pattern. Deep drainage of water beyond the reach of plant roots has mobilised salts stored in the landscape and caused watertables to rise, which has led to large areas becoming saline. Lack of growth in summer in pastures consisting of senescent annual-growing species and dormant C3 perennial grasses limits utilisation of the products of nitrogen mineralisation, which allows nitrate nitrogen to accumulate in summer and be readily leached by rainfall in autumn. This increases rates of soil acidification. Although there may be scope to reduce deep drainage by increasing pasture growth in spring in areas where there is little likelihood of summer rainfall, this is not the case in south-eastern Australia where significant falls of rain occur during summer and autumn.
34
Martin, Gary R., Laurie E. Twigg, and Lina Zampichelli. "Seasonal changes in the diet of the European rabbit (Oryctolagus cuniculus) from three different Mediterranean habitats in south-western Australia." Wildlife Research 34, no. 1 (2007): 25. http://dx.doi.org/10.1071/wr06044.
Full textAbstract:
Abstract.�Seasonal changes in the diet of rabbits from three temperate (Mediterranean) areas in south-western Australia were identified using microscopic determination of the percentage occurrence of various food groups in sampled stomachs. The sites differed in soil type and in the availability of summer perennials, native vegetation bush remnants (size of, and number of plant species), improved pastures, and summer rainfall, and hence, enabled a comparison of the diet of rabbits from the different vegetation communities. Although the diet of these rabbits was quite flexible, with some switching in food items occurring between seasons, there were marked differences in the proportion of monocotyledonous and dicotyledonous species eaten in each habitat. There was a strong reliance on seeds (1-5 species) during late spring and summer in all three habitats. Guildford grass (Romulea rosea) leaf and corms were a major component of the diet in the two habitats where this species was common. Further, as a result of the summer die-off of pasture species, there was a shift in where rabbits sourced food items during winter and summer. Pasture species were eaten during winter, but rabbits fed mainly on those dicotyledons found only in the surrounding scrub during summer. This suggests that rabbits may impact negatively upon such remnant vegetation at this time. Rabbits in all three habitats consumed several plant species with high water content (>54%) during summer, presumably to help maintain their water balance. Rabbits also consumed the seeds and foliage of several weed/nuisance species in each habitat, but any role of rabbits in weed dispersal was not determined.
35
Hughes, S. J., R. Snowball, K. F. M. Reed, B. Cohen, K. Gajda, A. R. Williams, and S. L. Groeneweg. "The systematic collection and characterisation of herbaceous forage species for recharge and discharge environments in southern Australia." Australian Journal of Experimental Agriculture 48, no. 4 (2008): 397. http://dx.doi.org/10.1071/ea07106.
Full textAbstract:
Australian temperate pasture Genetic Resource Centres (GRCs) co-ordinated a major program to introduce and screen herbaceous forage species. This program aims to expand the environments where such species could reduce recharge and manage discharge for the control of dryland salinity in southern Australia. The sustainability of agriculture, in Australia especially, depends on continued access to new germplasm to enable plant breeders to continue crop and forage improvement. The GRCs supported the selection and identification of promising new legume, grass and herb species as part of a national pasture evaluation program. In total, 671 species and 21 non-species-specific genera were identified as having potential to increase water use profitability of recharge lands and to improve the productivity of saline lands across a diverse range of agricultural environments in southern Australia. Through a series of activities, 201 of these species, representing legumes, herbs and grasses were identified as promising. These were then disseminated for evaluation in a range of environments across southern Australia. The progress of selected species was monitored and germplasm of the most promising 11 species and three leguminous genera was targeted for intensive acquisition and characterisation as the basis for selection and breeding. In addition to the identification and dissemination of promising species of immediate potential, a comprehensive collection of 544 native and exotic, wild and cultivated pasture species was conserved and is now available to service future plant improvement programs.
36
Robinson, JB, DJ Munnich, PC Simpson, and PW Orchard. "Pasture Associations and Their Relation to Environment and Agronomy in the Goulburn District." Australian Journal of Botany 41, no. 6 (1993): 627. http://dx.doi.org/10.1071/bt9930627.
Full textAbstract:
Pasture species form a variety of associations inn the cool temperate environment of the tablelands of New South Wales. Data from a survey of 65 paddocks on 34 farms in the Goulburn district of southern New South Wales were analysed using numerical classification methods to identify species associations. Of particular interest were the agronomic and environmental factors associated with the abundance of Danthonia spp. and Microlaena stipoides, which are persistent and useful native perennial grasses. The abundance of Danthonia spp. was negatively correlated with the abundance of exotic sown grasses (many species) and annual grass species (chiefly Vulpia spp.). M. stipoides abundance was similarly correlated with sown grass species, but had no correlation with annual grasses. It had a significant negative correlation with legume species abundance (chiefly Trifolium spp.). Sites with M. stipoides associations (n = 19 sites) had particular clearing and cultivation histories and low pH. Sites (n = 12) with a Danthonia spp. association also had particular clearing and cultivation histories, and occurred predominantly on soils derived from sedimentary parent material (11/12 sites). This association also had significantly higher annual average and total superphosphate usage. Probable mechanisms by which the concurrent environmental and agronomic factors may have determined the observed associations are discussed. It is concluded that the numerical classification system employed here revealed useful species association-site grouping units and contributed significantly to the interpretation of these data.
37
McCown, RL. "Being realistic about no-tillage, legume ley farming for the Australian semi-arid tropics." Australian Journal of Experimental Agriculture 36, no. 8 (1996): 1069. http://dx.doi.org/10.1071/ea9961069.
Full textAbstract:
There is a long tradition of expectation that, in time, land use in the better-endowed areas of Australia's semi-arid tropics would intensify from beef production on grassy woodlands to broadacre production of dryland crops. However, successive development attempts have yet to result in a substantial field crop industry. This paper reflects on a recent 20-year research and development episode in which ley farming, so successful in the wheat-sheep zone of southern Australia, was adapted and trialed in the tropical north. The system tested in the tropics was one which featured (i) coarse grain crops in rotation with legume leys and (ii) cattle grazing native pasture in the crop growing season and ley and crop residues in the dry season. It can be concluded that this system is technically successful. But compared with the ley system in southern Australia, the benefits of pasture legumes are less efficiently captured, both in the animal and the crop production enterprises. In addition, in this climate and on these soils, pastures with the high legume composition needed to substantially substitute for nitrogen fertiliser in the crop phase pose a serious threat of soil acidification. In contrast to legume leys, the advantage of no-tillage, mulch farming practices over conventional cultivation is much greater in this semi-arid tropical region than in temperate or Mediterranean areas: by slowing evaporation, mulch is often crucial in reducing high temperature injury or impedance to emerging seedlings as well as reducing the deleterious effects of intensive summer rainfall. But even with this improvement the climatic risks in dryland grain cropping remain a strong deterrent to crop industry development. Today, the findings from past experimentation, accrued farming experience, and new information products combine to provide what seem to be more realistic expectations for agriculture in this region. Even with the 'best' technology, this region suffers comparative disadvantage with respect to dryland field crop production and marketing. However, the region enjoys comparative advantages in the production of several other types of commodities, and a more realistic approach to 'Research and Development' includes a shift of resources toward activities with production and marketing advantages.
38
Reed, K. F. M., Z. N. Nie, S. Miller, B. F. Hackney, S. P. Boschma, M. L. Mitchell, T. O. Albertsen, et al. "Field evaluation of perennial grasses and herbs in southern Australia. 1. Establishment and herbage production." Australian Journal of Experimental Agriculture 48, no. 4 (2008): 409. http://dx.doi.org/10.1071/ea07135.
Full textAbstract:
To review pasture species for regions with 465–680 mm average annual rainfall, 22 perennial grasses and herbs were evaluated for pasture establishment and productivity in four states at seven locations where the arrest of groundwater recharge is considered necessary to ameliorate dryland salinity. Species represented introduced and native, temperate and subtropical grasses, chicory (Cichorium intybus L.) and plantain (Plantago lanceolata L.). This report describes establishment and yield; the following paper describes persistence and root characteristics. Yields were measured over 2–3 years except at one site, which suffered severe drought. Perennial ryegrass (Lolium perenne L., cv. Avalon) and tall fescue (Festuca arundinacea Schreb. = syn. Lolium arundinaceum. (Schreb.) Darbysh., cvv. AU Triumph and Resolute MaxP), cocksfoot (Dactylis glomerata L., cv. Porto) and phalaris (Phalaris aquatica L., cv. Holdfast and Australian) were the most productive species, with dry matter (DM) yields of 13.6–15.1 t/ha. For summer growth, Porto and Rhodes grass (Chloris gayana Kunth, cv. Katambora) were the most productive species; relative to Australian in summer, Porto and Katambora produced 41% and 26% more DM, respectively (95% confidence). Perennial ryegrass (cv. Avalon), tall fescue (cv. Resolute MaxP) and chicory (cv. Grouse) were particularly valuable for autumn growth; Avalon was 30% more productive than Australian. Tall fescue (cv. Resolute MaxP) was 32% more productive than Australian in winter. Avalon and AU Triumph were the most productive grasses and herbs in spring. Based on natural rainfall over the 2–3 years of measurement, the mean water use productivity, ignoring any runoff, was 10.5 kg DM/ha.mm for the three most productive species. Apart from kangaroo grass (Themeda triandra Forssk), native grasses gradually established, but over a prolonged period weeping grass (Microlaena stipoides (Labill.) R.Br., cv. Wakefield) was the most rapid. Perennial ryegrass, tall fescue, cocksfoot and phalaris maintained productive yields across a diverse range of soils and climates. Exploration of the diversity within these species in a nationally coordinated program of genetic improvement appears warranted for improving reliability and expanding the zone of adaptation.
39
Russell, JS. "Soil treatment, plant species and management effects on improved pastures on a solodic soil in the semi-arid subtropics. I. Dry matter and botanical composition." Australian Journal of Experimental Agriculture 25, no. 2 (1985): 367. http://dx.doi.org/10.1071/ea9850367.
Full textAbstract:
Pastures of Rhodes grass (Chloris gayana), temperate legumes (annual medics) and a tropical legume (siratro) were established on a solodic soil in 1973-74 at Kogan in the semi-arid subtropics of southern Queensland. The effect of soil treatments, sown pasture species and cattle stocking rates on dry matter yields and botanical composition were measured during 1974-79. Nitrogen deficiency was a key factor limiting herbage production. Increased nitrogen in the ecosystem applied as fertilizer increased mean presentation dry matter of Rhodes grass pastures from 990 to 3443 kg/ha. Use of hydrated lime and gypsum (HLG) and annual medics with Rhodes grass increased dry matter yields from 990 to 1773 kg/ha. Where HLG had been applied, the annual medics re-established from seed each autumn and early winter throughout the period studied. Siratro established well at sowing and contributed initially to herbage production but then declined to almost zero. Deep subsoiling had no significant effect on dry matter yields or siratro persistence. Applied phosphorus at 48 kg Plha at establishment significantly increased herbage yields of Rhodes grass compared with 24 kg P/ha but no significant effects at either rate were found with a further 60 kg P/ha applied as 12 kg P/ha.year. Rhodes grass, which is tolerant of high soil sodium and magnesium status, maintained frequencies above 90% in treatments where the levels of nitrogen and phosphorus were high and when grazed at 0.62 steers/ha. However, deterioration occurred where nitrogen and phosphorus were lower or grazing pressure was higher, resulting in an ingress of native grasses. Twenty-five volunteer grass species were identified, the main genera being Eragrostis and Chloris. The need for a self-regenerating annual summer-growing legume in this environment is discussed.
40
Graham, J. F., B. R. Cullen, G. M. Lodge, M. H. Andrew, B. P. Christy, P. J. Holst, X. Wang, S. R. Murphy, and A. N. Thompson. "SGS Animal Production Theme: effect of grazing system on animal productivity and sustainability across southern Australia." Australian Journal of Experimental Agriculture 43, no. 8 (2003): 977. http://dx.doi.org/10.1071/ea02197.
Full textAbstract:
The effects of various grazing management systems on sown, naturalised, and native pastures were studied at 6 different locations in the temperate high rainfall zone (HRZ, >600 mm rainfall/year) of southern Australia, as part of the Sustainable Grazing Systems (SGS) Program. The treatments examined had different pasture species and fertiliser management, with grazing method ranging from set stocking (continuous grazing) to rotation with rests based on pre- and post-grazing herbage mass or season and plant phenology. Sites were located at: Albany, Western Australia; Manilla, Barraba, Nundle, New South Wales; (grazed by wethers); and Carcoar, New South Wales; Maindample, Ruffy, north-east Victoria; Vasey, western Victoria; (grazed by ewes and lambs).Grazing method significantly (P<0.001) influenced stocking rate (expressed as dry sheep equivalents (DSE)/ha), but effects were not consistent across sites. At Vasey the stocking rate of the rotation treatments ranged from 5 to 23% higher than the set stocked treatments depending upon year. For all sites, significant factors (P<0.001) affecting stocking rate were soil Olsen P, soil pH, grazing management (resting), legume percent, and an index of growing season effectiveness. Although total annual rainfall had a significant effect (P<0.002) in an initial analysis, its influence became non-significant (P>0.05), when a growing season index (P<0.001) was used. Non-significant (P>0.05) factors included solar radiation, annual average temperature, fertiliser applied in the current year, and average annual perennial and broadleaf percent composition. The implications of these data for productivity and sustainability (as assessed by perenniality and water use) were encouraging. Generally, there were positive relationships between increased stocking rate and the probability of achieving a zero mm soil water surplus in winter, and between increased productivity and the proportion of perennial grass species where extremes of treatments were compared at each site. The results indicate that stocking rate can be increased without jeopardising sustainability, that grazing management can bring about more sustainable pastures, that there is scope to increase productivity particularly through increasing soil fertility, and growing season length can be used to predict potential carrying capacity. These are positive outcomes that graziers in the HRZ of southern Australia can use to enhance productivity (thus profitability) and sustainability.
41
Assad, E. D., H. S. Pinto, S. C. Martins, J. D. Groppo, P. R. Salgado, B. Evangelista, E. Vasconcellos, et al. "Changes in soil carbon stocks in Brazil due to land use: paired site comparisons and a regional pasture soil survey." Biogeosciences Discussions 10, no. 3 (March 21, 2013): 5499–533. http://dx.doi.org/10.5194/bgd-10-5499-2013.
Full textAbstract:
Abstract. In this paper we calculated soil carbon stocks in Brazil using 17 paired sites where soil stocks were determined in native vegetation, pastures and crop-livestock systems (CPS), and in other regional samplings encompassing more than 100 pasture soils, from 6.58° S to 31.53° S, involving three major Brazilian biomes: Cerrado, Atlantic Forest, and the Pampa. The average native vegetation soil carbon stocks at 10 and 30 cm soil depth were equal to approximately 33 and 65 Mg ha−1, respectively. In the paired sites, carbon losses of 7.5 Mg ha−1 and 11.9 Mg ha−1 in CPS systems were observed at 10 cm and 30 cm soil depth averages, respectively. In pasture soils, carbon losses were similar and equal to 8.3 Mg ha−1 and 12.2 Mg ha−1 at 10 cm and 30 cm soil depths, respectively. The average soil δ13C under native vegetation at 10 and 30 cm depth were equal to −25.4‰ and −24.0‰, increasing to −19.6 ‰ and −17.7‰ in CPS, and to −18.9‰, and −18.3‰ in pasture soils, respectively; indicating an increasing contribution of C4 carbon in these agrosystems. In the regional survey of pasture soils, the soil carbon stock at 30 cm was equal to approximately 51 Mg ha−1, with an average δ13C value of −19.6‰. Key controllers of soil carbon stock at pasture sites were sand content and mean annual temperature. Collectively, both could explain approximately half of the variance of soil carbon stocks. When pasture soil carbon stocks were compared with the average soil carbon stocks of native vegetation estimated for Brazilian biomes and soil types by Bernoux et al. (2002) there was a carbon gain of 6.7 Mg ha−1, which is equivalent to a carbon gain of 15% compared to the carbon soil stock of the native vegetation. The findings of this study are consistent with differences found between regional comparisons like our pasture sites and local paired study sites in estimating soil carbon stocks changes due to land use changes.
42
Assad, E. D., H. S. Pinto, S. C. Martins, J. D. Groppo, P. R. Salgado, B. Evangelista, E. Vasconcellos, et al. "Changes in soil carbon stocks in Brazil due to land use: paired site comparisons and a regional pasture soil survey." Biogeosciences 10, no. 10 (October 1, 2013): 6141–60. http://dx.doi.org/10.5194/bg-10-6141-2013.
Full textAbstract:
Abstract. In this paper we calculated soil carbon stocks in Brazil studying 17 paired sites where soil stocks were determined in native vegetation, pastures and crop-livestock systems (CPS), and in other regional samplings encompassing more than 100 pasture soils, from 6.58 to 31.53° S, involving three major Brazilian biomes: Cerrado, Atlantic Forest, and the Pampa. The average native vegetation soil carbon stocks at 10, 30 and 60 cm soil depth were equal to approximately 29, 64, and 92 Mg ha−1, respectively. In the paired sites, carbon losses of 7.5 Mg ha−1 and 11.6 Mg ha−1 in CPS systems were observed at 10 cm and 30 cm soil depths, respectively. In pasture soils, carbon losses were similar and equal to 7.5 Mg ha−1 and 11.0 Mg ha−1 at 10 cm and 30 cm soil depths, respectively. Differences at 60 cm soil depth were not significantly different between land uses. The average soil δ13C under native vegetation at 10 and 30 cm depth were equal to −25.4‰ and −24.0‰, increasing to −19.6‰ and −17.7‰ in CPS, and to −18.9‰, and −18.3‰ in pasture soils, respectively; indicating an increasing contribution of C4 carbon in these agrosystems. In the regional survey of pasture soils, the soil carbon stock at 30 cm was equal to approximately 51 Mg ha−1, with an average δ13C value of −19.67‰. Key controllers of soil carbon stock in pasture sites were sand content and mean annual temperature. Collectively, both could explain approximately half of the variance of soil carbon stocks. When pasture soil carbon stocks were compared with the average soil carbon stocks of native vegetation estimated for Brazilian biomes and soil types by Bernoux et al. (2002) there was a carbon gain of 6.7 Mg ha−1, which is equivalent to a carbon gain of 15% compared to the carbon soil stock of the native vegetation. The findings of this study are consistent with differences found between regional comparisons like our pasture sites and plot-level paired study sites in estimating soil carbon stocks changes due to land use changes.
43
Anon, A. "The High Country Environment." NZGA: Research and Practice Series 4 (January 1, 1995): 3–9. http://dx.doi.org/10.33584/rps.4.1995.3328.
Full textAbstract:
The most important environmental factors influencing farming and the choice of pasture species are: l Temperature l Soil moisture 0 Soil fertility 0 Pasture management. Temperature and moisture gradients define the general pattern of soils, original vegetation and present farming systems within New Zealand (Figure 1). With decreasing moisture and temperature, pasture production falls, so pasture yields in the high country are generally much lower than elsewhere. The traditionally large size of both paddocks and runs in the high country was related to the low level of pasture yield from native vegetation.
44
Weller, Sandra, Singarayer Florentine, Bhagirath S. Chauhan, Ako Mahmood, and Arunthathy Florentine. "Effects of various ecological factors on the germination of two crop and pasture weed species, Vulpia bromoides and Vulpia myuros." New Zealand Plant Protection 72 (July 26, 2019): 135–46. http://dx.doi.org/10.30843/nzpp.2019.72.231.
Full textAbstract:
Vulpia species (silver grasses), including V. bromoides and V. myuros, are native to the Mediterranean, Middle East and Eurasia, but have become dispersed worldwide. These two species reduce the grazing quality of pastures, frequently co-occur and are often associated with poor-quality acidic soils. This study investigated two species, Vulpia bromoides and V. myuros. Germination trials tested the effects of seasonal temperature, light,pH, moisture, salinity, pre-germination heat shock and smoke, and seed burial depth. Vulpia bromoides germinated well regardless of temperature or light (>80%, all conditions), whereas V. myuros preferred lower temperatures and absence of light (97%, 7/17oC in 24-h dark). Under different culture conditions, the two species germinated well across the pH range 4 to 10 (>85%). Reduced moisture, pre-germination heat shock and smoke, and increased burial depth reduced germination and emergence of both species. Preventing germination of these species in pastures must begin before or during winter. Fire may be useful for control, butsufficiently high temperatures must be achieved to kill seeds. Tillage to bury seeds, prior to pasture renovation, may prevent germination of seeds.
45
Ivo, Israel Oliveira, Marcelo Sacardi Biudes, Rayanna de Oliveira Costa, Nadja Gomes Machado, Luiz Octávio Fabrício Do Santos, and Altemar Lopes Pedreira Junior. "VARIAÇÃO TEMPORAL DE PARÂMETROS BIOFÍSICOS DA SUPERFÍCIE POR IMAGENS Landsat 5 EM DIFERENTES COBERTURAS DO SOLO EM UMA ÁREA DE TRANSIÇÃO DE CERRADO E PANTANAL EM MATO GROSSO." Nativa 8, no. 5 (September 25, 2020): 597–602. http://dx.doi.org/10.31413/nativa.v8i5.10064.
Full textAbstract:
A substituição da vegetação nativa e a sazonalidade climática modificam os parâmetros biofísicos da superfície. Como 50% do Cerrado tem sido convertido em lavouras e pastagens, o objetivo desse estudo foi avaliar a variação temporal de parâmetros biofísicos em áreas nativas e convertidas em uma área de transição entre Cerrado e Pantanal no Mato Grosso. O estudo foi conduzido na Fazenda Experimental da UFMT (15° 51’ 15.23’’ S e 56° 04’ 13.50’’ W) com imagens do sensor TM-Landsat 5 entre abril e setembro de 2011. O Índice de Vegetação da Diferença Normalizada (NDVI), o albedo da superfície (α) e a temperatura da superfície (Ts) foram estimados em áreas de Cerrado strito sensu (CER), pastagem de Brachiaria brizantha (PAS) e mangueiral (MAN). Os maiores valores de NDVI e menores valores de α e Ts foram observados nas áreas mais densamente vegetadas. O Cerrado apresentou menores valores de α e a MAN apresentou maiores valores de NDVI ao longo de todo experimento. A substituição da cobertura nativa da região de transição de Cerrado e Pantanal por vegetação exótica modificou significativamente os parâmetros biofísicos avaliados, com potencial de modificar os balanços de radiação, energia, carbono da superfície. Palavras-chave: desmatamento; sensoriamento remoto; aquecimento regional. TEMPORAL VARIATION OF BIOPHYSICAL PARAMETERS OF THE SURFACE BY LANDSAT 5 IMAGES IN DIFFERENT SOIL COVERS IN A TRANSITIONAL AREA OF CERRADO AND PANTANAL IN MATO GROSSO ABSTRACT: The substitution of native vegetation and climatic seasonality modify the surface biophysical parameters. As 50% of the Cerrado has been converted to crops and pastures, the objective of this study was to evaluate the temporal variation of biophysical parameters in native areas and converted into a transition area between Cerrado and Pantanal in Mato Grosso. The study was conducted at the UFMT Experimental Farm (15° 51’ 15.23’’ S e 56° 04’ 13.50’’ W) with TM Landsat 5 images between April and September 2011. The Normalized Difference Vegetation Index (NDVI), and the surface albedo (α) and surface temperature (Ts) were obtained from a Cerrado stricto sensu (CER), a pasture of Brachiaria brizantha (PAS) and a mangrove (MAN). The highest NDVI values and lowest α and Ts values were observed in the most densely vegetated areas. The replacement of the native cover of the Cerrado and Pantanal transition region with exotic vegetation significantly modified the biophysical parameters evaluated, with the potential to modify the radiation, energy and carbon balances of the surface. Keywords: deforestation; remote sensing; regional warming.
46
Santos, Patricia Menezes, Tadeu Vinhas Voltolini, Ana Clara Rodrigues Cavalcante, José Ricardo Macedo Pezzopane, Magna Soelma Beserra de Moura, Thieres George Freire da Silva, Giovana Maranhão Bettiol, and Pedro Gomes da Cruz. "Mudanças Climáticas Globais e a Pecuária: Cenários Futuros para o Semiárido Brasileiro (Global Climatic Changes and Animal Production: Future Scenarios for the Brazilian Tropical Semiarid)." Revista Brasileira de Geografia Física 4, no. 6 (March 21, 2012): 1176. http://dx.doi.org/10.26848/rbgf.v4i6.232765.
Full textAbstract:
Os sistemas de produção animal no Semiárido brasileiro podem ser vulneráveis às mudanças climáticas. Cenários futuros para a produção de Brachiaria brizantha, Panicum maximum, Cenchrus ciliaris e Opuntia fícus indica foram analisados para a identificação de áreas mais vulneráveis. A partir dos modelos já disponíveis, foram identificadas algumas áreas de maior vulnerabilidade, o que possibilitou a indicação de alternativas de adaptação dos sistemas de produção para mitigação de possíveis impactos negativos das mudanças climáticas globais sobre a produção animal do Semiárido brasileiro. O desenvolvimento de técnicas para o uso sustentável da Caatinga como pasto nativo contribuirá para reduzir a degradação deste bioma e os riscos de desertificação da região. Novas variedades de plantas forrageiras, tanto de exóticas quanto de espécies nativas, melhor adaptadas para as condições de cenários climáticos futuros poderão ser desenvolvidos através do melhoramento vegetal. O uso de irrigação de pastagens e o aproveitamento de co-produtos na alimentação dos animais contribuirão para o aumento de produtividade e para a redução da pressão sobre a vegetação nativa. Diversos grupos de pesquisa têm desenvolvido modelos melhores para projeção regionalizada de chuva e de temperatura. O desenvolvimento desses modelos permitirá uma investigação mais precisa dos possíveis impactos das mudanças climáticas globais sobre a pecuária no semiárido brasileiro. Palavras - chave: pastagem; pastagem nativa; produção animal; sistemas de produção. Global Climatic Changes and Animal Production: Future Scenarios for the Brazilian Tropical Semiarid ABSTRACTThe animal production systems on semi-arid areas of Brazil may be vulnerable to global climatic changes. Future scenarios for the production of Brachiaria brizantha, Panicum maximum, Cenchrus ciliaris and Opuntia fícus indica were analysed to identify more vulnerable areas. Using the models already available, areas with higher vulnerability were identified and alternatives for adaptation of current animal production systems were proposed to mitigate possible negative impacts of global climatic changes. The development of techniques for the sustainable use of Caatinga as native pasture may contribute to reduce degradation of the Caatinga biome and to reduce risks of desertification. New genotypes of exotic and native forage species, better adapted to future climatic conditions, may be developed through plant breeding. Pasture irrigation and use of residues from industries as animal feed will improve productivity and reduce pressure over Caatinga biome. Several research groups are developing better models to a better regionalized prediction of rainfall and temperature. The development of this models will allow a more precise investigation of the possible impacts of the climatic changes on animal production systems on semi-arid area of Brazil. Keywords:grassland; rangeland; animal production; production systems.
47
Uchoa, Manoel Araécio, and Marino Miloca Rodrigues. "Dung beetles (Coleoptera: Scarabaeoidea) population patterns in three environments in the Midwest of Brazil." EntomoBrasilis 12, no. 1 (April 30, 2019): 19–26. http://dx.doi.org/10.12741/ebrasilis.v12i1.825.
Full textAbstract:
Abstract. Scarabaeids are economically very important due to their provision of several environmental services, in particular to cattle rearing, because they are highly active in the decomposition of cattle feces in pasture environments. The objectives of this research were to evaluate the season of dung beetle occurrence, and the effect of weather on their abundance and species richness in different environments. A total of 44,355 adults were captured: 105 samples in each of three different environments (agroecosystem, pasture and native forest), adding 315 samples for two consecutive years (November 2005 to November 2007). Fifty-three species were found in that three environments,being 51 of Scarabaeidae, including two subspecies of Dichotomius, and two of Hybosoridae: Coilodes humeralis (Mannerheim) and Coilodes sp.1. We verified a correlation between temperature and rainfall and the occurrence of Scarabaeidae species associated with bovine feces. The species with highest population levels were:Labarrus pseudolividus Balthasar in the pasture, and Ataenius platensis (Blanchard) in both: agroecosystem and native semi-deciduous forest. There was a positive correlation between higher temperature and rainfall with an increase in the abundance of adult dung beetles in the environments. The number of adults caught and species richness of dung beetles was significantly greater in the pasture when temperature and rainfall were higher. The combined analysis of the three environments showed that from Oct to Dec, when temperature and precipitation were highest, there was a significant increase in the capture of dung beetles in the traps in comparison to the period from Apr to Jul (coldest season).Esquemas populacionais dos escaravelhos (Coleoptera: Scarabaeoidea) em três ambientes no Centro-Oeste do BrasilResumo. Scarabeídeos são economicamente muito importantes devido à pestação de vários serviços ambientais, em especial para bovinocultura, porque atuam fortemente na decomposição de fezes bovinas em ambientes de pastagem. Os objetivos desta pesquisa foram avaliar as épocas de ocorrência das espécies de besouros “rola bosta” e o efeito do clima sobre a abundância e riqueza de suas espécies em diferentes ambientes. Um total de 44.355 adultos foram capturados: 105 amostras em cada um dos diferentes ambientes (agroecossistema, pastagem e floresta nativa), somando 315 amostras durante dois anos consecutivos (novembro de 2005 a novembro de 2007). Cinquenta e três espécies foram encontradas nos três ambientes durante dois anos de amostragem, 51 de Scarabaeidae (incluindo duas subespécies de Dichotomius) e duas espécies de Hybosoridae: Coilodes humeralis (Mannerheim) e Coilodes sp.1. Houve correlação entre a temperatura e as chuvas com as épocas de ocorrência das espécies Scarabaeidae associadas com fezes bovinas. As espécies com níveis populacionais mais elevados foram: Labarrus pseudolividus Balthasar na pastagem e Ataenius platensis (Blanchard) em ambos: agroecossistema e floresta nativa semidecídua. Existe uma correlação positiva entre temperaturas mais elevadas e chuvas com aumento na captura dos “rola bosta” em armadilhas. O número de adultos capturados e a riqueza em espécies dos “rola bosta” capturados foi significativamente superior quando a temperatura e a pluviosidade foram mais altas. A análise combinada dos três ambientes mostrou que de outubro a dezembro, quando a temperatura e a precipitação foram mais elevadas, houve um aumento significativo na captura destes besouros nas armadilhas.
48
Lodge, G. M. "The role and future use of perennial native grasses for temperate pastures in Australia." New Zealand Journal of Agricultural Research 37, no. 3 (September 1994): 419–26. http://dx.doi.org/10.1080/00288233.1994.9513079.
Full text
49
Villalba, Juan J., Kathy J. Soder, and Emilio A. Laca. "Understanding Diet Selection in Temperate Biodiverse Pasture Systems." Rangeland Ecology & Management 62, no. 5 (September 2009): 387–88. http://dx.doi.org/10.2111/09-003.1.
Full text
50
Lodge, G. M., and S. R. Murphy. "Ground cover in temperate native perennial grass pastures. II. Relationship with herbage and litter mass." Rangeland Journal 24, no. 2 (2002): 301. http://dx.doi.org/10.1071/rj02017.
Full textAbstract:
Studies were conducted to examine the relationship between ground cover and herbage mass; ground cover and litter mass; herbage mass and litter mass, and, ground cover and total (herbage and litter) mass for two grazed, native pastures in the high rainfall, temperate rangelands of northern NSW. Ground cover was visually estimated by two experienced observers, litter (unattached plant material) was collected and herbage mass was estimated by harvesting to ground level in 30 quadrats (40 by 40 cm). Data were collected for 16 sampling times at the change of season and from spring 1997 to spring 2000 (a total of 465 quadrats at each site) and examined by regression analysis for the mean data for each level of ground cover and for data from individual quadrats. The relationship between ground cover and herbage, litter or total mass was logarithmic at each site. The logarithmic nature of the relationship reflected the occurrence of low herbage, litter and total mass even when ground cover was 100%. For the mean data, herbage and total mass accounted for 68–77% of the variation in ground cover, but for the individual quadrat data these variables accounted for 42–53% and 43–55%, respectively of this variation. Litter and herbage mass had a low correlation (R2<~0.20) and for the mean data litter mass accounted for around 40–60% of the variation in ground cover, compared with 15–21% for the individual quadrats. Some seasonal differences in these relationships were apparent and these were attributed to the occurrence of annual forb and legume species that had different growth habits to those of the native perennial grasses. For these pastures the data indicated that herbage mass could not be used as a surrogate measure of ground cover or litter mass.