Lethbridge M.R.,Flinders University |
Anderson N.,Flinders University |
Harper M.L.,Flinders University |
Gee P.,Rural Solutions SA
Rangeland Journal | Year: 2010
We analysed the movement of seven female camels collared in the Anangu Pitjantjatjara Yankunytjatjara Lands of South Australia. Understanding the movement patterns of feral camels and subsequently where high densities are likely to threaten biodiversity and cultural assets, provides land managers and government agencies with information and decision support tools to manage camel impacts. Accordingly, we tested if there were any seasonal changes in camel movement, any measurable separation between home range and migration, and any relationship between broader camel landscape use, rainfall and mountainous terrain. We fitted ARGOS GPS satellite collars to seven female camels in South Australia during August 2007 and found evidence to suggest that over a 12-month study period, some camels had returned to locations that they had previously visited. This cyclic movement pattern was more regular up to ∼50 days, however, one collared individual returned to a previous location after 300 days. Despite only having a small sample size, we did find camels moving into areas that received higher rainfalls in the warmer months and possibly some attraction of these camels to steep mountainous terrain over this period. © Australian Rangeland Society 2010.
Coventry D.R.,University of Adelaide |
Yadav A.,Haryana Agricultural University |
Poswal R.S.,Directorate of Wheat Research |
Sharma R.K.,Directorate of Wheat Research |
And 8 more authors.
Field Crops Research | Year: 2011
Wheat in Haryana (NW India) is grown as a winter crop in an annual sequence with rice, cotton, pearl millet or cluster bean as the main monsoon crops. Higher wheat yields in Haryana are associated with the use of modern varieties, increase in fertiliser use, improved irrigation practice and conservation tillage, and the recommendation to farmers for N fertiliser rates and timing and irrigation practice have an emphasis on optimising yield and input efficiencies. In India the importance to consumers of product quality does exist and, although the market place presently does not actively reward farmers for better quality wheat, the need for creating suitable and targeted marketing opportunities is now recognised. This paper examines aspects of input efficiencies and focuses on combinations of N-fertiliser and irrigation input in wheat crops grown with these four rotations (rice-wheat, cotton-wheat, pearl millet-wheat and cluster bean-wheat). Management practices that optimise grain production as well targeting grain that achieves best chapatti (Indian flat bread) quality are evaluated within a split-plot experiment where 4 irrigation schedule treatments were split with nitrogen management treatments involving a 2-way or 3-way split of N fertiliser. With the rice-wheat system, there were no differences between different split timings of N with grain yield, however with the 3 other wheat systems the 3 way split of N-fertiliser application, with N applied equally at N-fertiliser applied at seeding, early tillering and first node stage, always gave the highest yield. With all 4 rotations the highest protein level was achieved (range 11.8-12.5%) with this 3-way N application split. Grain yield increased in a step-wise manner as additional irrigation was implemented with all rotations and the highest protein outcomes were achieved with the least irrigations. The apparent recovery of N fertiliser applied was similar and highest with the 3-way split, and the 2-way split that did not include a basal N fertiliser application. Different rates of N fertiliser were included in separate experiments using the 3-way split of N application, and with the rice-wheat rotation the GreenSeeker instrument was used to establish the rate for the third application of N. The application of extra N-fertiliser with the non rice-wheat rotations produced no additional grain yield with an increase in the N-fertiliser input beyond 150kgNha-1, although protein and N-content increased incrementally. Grain hardness and chapatti score trended higher with increases in N-fertiliser input but the increases were relatively small. The use of the GreenSeeker instrument with the rice-wheat rotation resulted in N saving of 21-25kgNha-1 with similar grain yield, protein and grain hardness to that provided by using the recommended 150kgNha-1. Where the GreenSeeker was used the apparent recovery was 70-75% compared with 60% with the wheat receiving the recommended 150kgNha-1, suggesting farmers are likely to be over-fertilising their wheat crop. The best yields obtained in these experiments were about 5.5-6.0tha-1 and these yields are consistent with a decade-long attainable yield identified for wheat in rice-wheat rotation for Haryana. If farmers can achieve market recognition for chapatti quality, and with the use of appropriate varieties, then farmers can assume that the best practice outlined here for optimising grain yield with integrated nutrient and soil management will be the same practice that optimises chapatti quality. © 2011 Elsevier B.V.
Coventry D.R.,University of Adelaide |
Poswal R.S.,Indian Institute of Wheat and Barley Research |
Yadav A.,Haryana Agricultural University |
Riar A.S.,University of Adelaide |
And 10 more authors.
Agricultural Systems | Year: 2015
An extensive stratified survey was conducted in two different wheat growing seasons in all districts of Haryana (India) to evaluate current agronomic practices and assess performance in wheat production with the purpose of identifying where farmers can make further changes in practices. The survey involved 116 villages (927 farmers) in 2008 and 103 villages (823 farmers) in 2010. Different sized farming operations from each village were surveyed to represent all socio-economic categories of farmers. Agronomic inputs (tillage method, fertilizer practice, variety choice, time of sowing, irrigation, and rotation practice) and yield data are presented as mean data, and individual farmer's information is represented by regression tree (RT) analysis to highlight primary associations between cropping management and wheat yield and the technical efficiency (TE) measure. TE was calculated using the key agronomic variables obtained from the survey, and the farms with the highest TE values were assessed as having the superior 'best practice' technology. In the districts where the rice-wheat rotation was adopted, there was an overall higher level of TE. Where rice-wheat rotation is the main cropping practice (for example in Kaithal and Kurukshetra), many of the farmers have adopted zero tillage farming methods, with one third of farmers in Kaithal using zero tillage for planting wheat. In contrast, in Sirsa district where cotton was favoured by the farmers as their monsoon season crop, there were no farms where zero tillage was practised. Also, there was also no zero tillage farming where the pearl millet/cluster bean rotation was used as the monsoon season crop. In most cases farmers use a two applications of nitrogen fertilizer applied post-emergence, particularly in the rice-wheat and cotton-wheat districts. The survey also showed that application of potassium fertilizer and use of zinc is regionally specific and this is consistent with the soil maps that show the potential for deficiency of these nutrients in Haryana districts. Sowing in the rice-wheat districts was mostly at the recommended time in early November. The highest number of irrigations occurred in the districts using the pearl millet-wheat and cluster bean-wheat rotations where sprinkler irrigation is the main application practice. The analysis of TE provides a useful comparison when the 5 different farm size categories are separated. There was no difference in TE with farm size, suggesting the message concerning best practice for wheat production is available to and adopted by farmers irrespective of scale of operation. This analysis highlights where extension messages could be focused, whether for zero tillage in the non-rice districts, management of macro-nutrients, or the targeted use of micronutrients. © 2015 Elsevier Ltd.
Sanderman J.,CSIRO |
Sanderman J.,Woods Hole Oceanographic Institution |
Reseigh J.,Rural Solutions SA |
Wurst M.,Rural Solutions SA |
And 2 more authors.
PLoS ONE | Year: 2015
Rotational grazing management strategies have been promoted as a way to improve the sustainability of native grass-based pasture systems. From disturbance ecology theory, rotational grazing relative to continuous grazing can increase pasture productivity by allowing vegetation to recover after short intense grazing periods. This project sought to assess whether soil organic carbon (SOC) stocks would also increase with adoption of rotational grazing management. Twelve pairs of rotationally and continuously grazed paddocks were sampled across a rainfall gradient in South Australia. Pasture productivity approximated as the normalized difference vegetation index (NDVI) was on average no different between management categories, but when the data from all sites were aggregated as log response ratios (rotational/continuous) a significant positive trend of increasing NDVI under rotational grazing relative to continuous grazing was found (R2 = 0.52). Mean SOC stocks (0-30 cm) were 48.3 Mg C ha-1 with a range of 20-80 Mg C ha-1 across the study area with no differences between grazing management categories. SOC stocks were well correlated with rainfall and temperature (multiple linear regression R2 = 0.61). After removing the influence of climate on SOC stocks, the management variables, rest periods, stocking rate and grazing days, were found to be significantly correlated with SOC, explaining 22% of the variance in SOC, but there were still no clear differences in SOC stocks at paired sites. We suggest three reasons for the lack of SOC response. First, changes in plant productivity and turnover in low-medium rainfall regions due to changes in grazing management are small and slow, so we would only expect at best small incremental changes in SOC stocks. This is compounded by the inherent variability within and between paddocks making detection of a small real change difficult on short timescales. Lastly, the management data suggests that there is a gradation in implementation of rotational grazing and the use of two fixed categories (i.e. rotational v. continuous) may not be the most appropriate method of comparing diverse management styles. © 2015 Sanderman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.