Looking back in time: can safe pasture utilisation rates be determined using commercial paddock data in the Northern Territory?

2011 ◽  
Vol 33 (2) ◽  
pp. 131 ◽  
Author(s):  
Dionne Walsh ◽  
Robyn A. Cowley

A ‘safe’ pasture utilisation rate is defined as the proportion of annual forage growth that can be consumed by domestic livestock without adversely affecting land condition in the long term. Pasture utilisation rates are thus a cornerstone of a sustainable grazing industry because they directly determine livestock carrying capacity. Until now, it has only been possible to determine utilisation rates in the Northern Territory via expensive and time-consuming grazing trials. Reliance on this method has limited the validation of safe utilisation rates for the range of land types used for pastoral production. This study tested an alternative cost-effective method for calculating utilisation rates based on an approach used previously in Queensland. The method retrospectively calculates utilisation rates using cattle records and modelled pasture growth from commercial paddocks in good land condition. The assumption underpinning the method is that paddocks in good land condition, with a long history of grazing, must have been managed in such a way as to achieve a safe level of pasture utilisation. Utilisation rates were calculated for 10 commercial paddocks on three properties in the Barkly Tableland region of the Northern Territory from 1999 to 2009. Animal intake for each paddock was calculated from detailed cattle records held in property databases. Pasture growth was estimated using simulation models and cross-checked with field measurements. An average utilisation rate of up to 25% of annual pasture growth was found to be safe on highly uniform, grey cracking-clays supporting Mitchell grass (Astrebla F. Muell. spp.) pastures. However, this level of utilisation had negative impacts on land condition on less resilient and preferentially grazed pasture communities in paddocks with a mix of land types. The implications of the results for carrying capacity, animal productivity and seasonal risk management are explored in this paper.

2021 ◽  
Author(s):  
Jean Grégoire Boero Rollo ◽  
John Richard Ordonez Varela ◽  
Tayssir Ben Ghzaiel ◽  
Cedric Mouanga ◽  
Arnaud Luxey ◽  
...  

Abstract Wireless Autonomous Nano-sensor Device (WAND) system is a disruptive cost-effective micro-system for well monitoring. It allows to realize pressure, temperature, inertial, and magnetic field measurements in harsh conditions; it also offers Bluetooth low-power communication and Wireless charging capabilities. Analysis’ results of an industrial offshore pilot realized in Congo (a world first in O&G industry in such complex environment), and major improvements implemented after this pilot are reported in this paper. Accomplished advancements comprise hardware and software developments extending operation lifetime, and simplifying on-site utilization. To date, there is not a commercial solution of this type in the market, the realization of this project is a real innovation allowing practical and low-cost monitoring during well intervention while minimizing the risks associated with standard Rigless intervention. Other applications regarding dry-tree wells on tension-leg platforms (TLP), drilling and completion operations, and pipeline monitoring are being investigated, too.


1993 ◽  
Vol 20 (1) ◽  
pp. 127 ◽  
Author(s):  
B Walsh ◽  
PJ Whitehead

Since 1986 the Conservation Commission of the Northern Territory has operated a programme to remove 'problem' saltwater crocodiles from waters in and adjoining the township of Nhulunbuy. Over a period of five years, 52 different saltwater crocodiles (44 male) were captured. Most (48) were released at remote sites designated by the traditional Aboriginal owners of the surrounding lands. Release distances from the township varied from 17 to 282 km (by coastline). Many crocodiles (47.9%), including those released at the most distant sites, returned to, and were subsequently recaptured at, the township. Total capture rates (initial captures and recaptures pooled) varied seasonally, with fewer crocodiles being caught in the cooler dry season. During the wet season capture rates remained high, but relatively fewer 'new' crocodiles were caught. Probability of recapture could not be related to distance and direction of release from the township, nor size and sex of the released crocodile. Frequency of capture of individual crocodiles (1-8 times) was also unrelated to these variables. The high rates of return indicate that relocation is unlikely to be an effective strategy for managing humancrocodile interactions, at least in areas where potential release sites already support saltwater crocodile populations near carrying capacity.


2018 ◽  
Vol 15 (7) ◽  
pp. 403 ◽  
Author(s):  
Chanida Puangpila ◽  
Jaroon Jakmunee ◽  
Somkid Pencharee ◽  
Wipada Pensrisirikul

Environmental contextA widespread pollutant in groundwater, rivers and lakes is nitrite, which is commonly determined batchwise by using colourimetry. The batchwise method, however, requires relatively large and expensive instrumentation, and hence is unsuitable for in-field measurements. This work introduces a simple and portable colourimetric analyser based on a mobile-phone camera for monitoring nitrite concentrations in environmental water samples. AbstractA cost-effective and portable colourimetric analyser installed on a mobile phone was used to measure nitrite in water samples in Chiang Mai City, Thailand. The colourimetric detection was based on the Griess reaction, in which nitrite ion reacts with sulfanilic acid under acidic conditions to produce a diazonium salt that further reacts with N-(1-naphthyl)-ethylenediamine dihydrochloride to form a red–violet azo dye. Under controlled conditions using a light-tight box with LED flash lights, images of the red–violet solution were captured using a built-in camera and further analysed by a program, Panalysis, on the mobile phone. The calibration graph was created by measuring the red colour intensity of a series of standard nitrite solutions from 0.09–1.8 mg N L−1. The calibration equation was then automatically stored for nitrite analysis. The results demonstrated good performance of the mobile phone analyser as an analytical instrument. The accuracy (RE <4%) and precision (RSD ≤ 1%, intra- and inter-day) were also obtained with a detection limit of 0.03 mg N L−1 and a sample throughput of 40 samples per hour. Our results establish this simple, inexpensive and portable device as a reliable in-field monitor of nitrite in environmental waters.


2021 ◽  
Vol 16 (2) ◽  
Author(s):  
Harkanwal Randhawa ◽  
Yuding Wang ◽  
Jen Hoogenes ◽  
Michael Uy ◽  
Bobby Shayegan ◽  
...  

Introduction: Suprapubic catheterization (SPC) is a fundamental skill required of urology trainees. A lack of affordable simulation models and unpredictability of bedside SPCs limit experiential learning opportunities. Our objective was to develop and initially validate a re-usable, low-cost, ultrasound (US)-compatible SPC simulator for acquiring skills that transfer to the bedside. Methods: The model was constructed using six components. Staff urologists and interventional radiologists (IRs) conducted a SPC and rated the model on three domains with multiple subcategories on a five-point Likert scale: anatomic realism; usefulness as a training tool; and global/overall reaction. Participants in our first-year urology “boot camp” received SPC training, practiced, and were evaluated via an objective structured clinical examination (OSCE). Staff ratings and OSCE scores determined the model’s initial face and content validity. Results: Twelve staff physicians participated in the study. The mean scores for urologists and IRs, respectively, were: anatomical realism: 4.10 and 3.70; usefulness as a training tool: 4.23 and 4.24; and overall reaction: 4.40 and 4.44. Staff strongly agreed that the model should be incorporated into the residency curriculum. Over the past four years, 25 boot camp participants scored a mean of 99.7% (±1.8) on the OSCE, with high technical performance and entrustment scores (4.8 and 4.7, respectively). The model cost $55 CAD. Conclusions: This novel, multiple-use, low-cost, easily reproducible US-compatible SPC simulator demonstrated initial face and content validity via high staff urologist and IR ratings and OSCE scores of first-year urology residents. Additional research is required for construct validation.


2021 ◽  
pp. 146808742110387
Author(s):  
Stylianos Doulgeris ◽  
Zisimos Toumasatos ◽  
Maria Vittoria Prati ◽  
Carlo Beatrice ◽  
Zissis Samaras

Vehicles’ powertrain electrification is one of the key measures adopted by manufacturers in order to develop low emissions vehicles and reduce the CO2 emissions from passenger cars. High complexity of electrified powertrains increases the demand of cost-effective tools that can be used during the design of such powertrain architectures. Objective of the study is the proposal of a series of real-world velocity profiles that can be used during virtual design. To that aim, using three state of the art plug-in hybrid vehicles, a combined experimental, and simulation approach is followed to derive generic real-world cycles that can be used for the evaluation of the overall energy efficiency of electrified powertrains. The vehicles were tested under standard real driving emissions routes, real-world routes with reversed order (compared to a standard real driving emissions route) of urban, rural, motorway, and routes with high slope variation. To enhance the experimental activities, additional virtual mission profiles simulated using vehicle simulation models. Outcome of the study consists of specific driving cycles, designed based on standard real-world route, and a methodology for real-world data analysis and evaluation, along with the results from the assessment of the impact of different operational parameters on the total electrified powertrain.


Fire ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 68
Author(s):  
Sarah A. Lewis ◽  
Peter R. Robichaud ◽  
Andrew T. Hudak ◽  
Eva K. Strand ◽  
Jan U. H. Eitel ◽  
...  

As wildland fires amplify in size in many regions in the western USA, land and water managers are increasingly concerned about the deleterious effects on drinking water supplies. Consequences of severe wildfires include disturbed soils and areas of thick ash cover, which raises the concern of the risk of water contamination via ash. The persistence of ash cover and depth were monitored for up to 90 days post-fire at nearly 100 plots distributed between two wildfires in Idaho and Washington, USA. Our goal was to determine the most ‘cost’ effective, operational method of mapping post-wildfire ash cover in terms of financial, data volume, time, and processing costs. Field measurements were coupled with multi-platform satellite and aerial imagery collected during the same time span. The image types spanned the spatial resolution of 30 m to sub-meter (Landsat-8, Sentinel-2, WorldView-2, and a drone), while the spectral resolution spanned visible through SWIR (short-wave infrared) bands, and they were all collected at various time scales. We that found several common vegetation and post-fire spectral indices were correlated with ash cover (r = 0.6–0.85); however, the blue normalized difference vegetation index (BNDVI) with monthly Sentinel-2 imagery was especially well-suited for monitoring the change in ash cover during its ephemeral period. A map of the ash cover can be used to estimate the ash load, which can then be used as an input into a hydrologic model predicting ash transport and fate, helping to ultimately improve our ability to predict impacts on downstream water resources.


Author(s):  
Sohini Roy Chowdhury ◽  
Caterina Scoglio ◽  
William H. Hsu

Prediction of epidemics such as Foot and Mouth Disease (FMD) is a global necessity in addressing economic, political and ethical issues faced by the affected countries. In the absence of precise and accurate spatial information regarding disease dynamics, learning- based predictive models can be used to mimic latent spatial parameters so as to predict the spread of epidemics in time. This paper analyzes temporal predictions from four such learning-based models, namely: neural network, autoregressive, Bayesian network, and Monte-Carlo simulation models. The prediction qualities of these models have been validated using FMD incidence reports in Turkey. Additionally, the authors perform simulations of mitigation strategies based on the predictive models to curb the impact of the epidemic. This paper also analyzes the cost-effectiveness of these mitigation strategies to conclude that vaccinations and movement ban strategies are more cost-effective than premise culls before the onset of an epidemic outbreak; however, in the event of existing epidemic outbreaks, premise culling is more effective at controlling FMD.


Weed Science ◽  
1985 ◽  
Vol 33 (S2) ◽  
pp. 25-32 ◽  
Author(s):  
R. J. Wagenet ◽  
P.S.C. Rao

Modeling is increasingly being used as a tool for the evaluation of the environmental fate of pesticides. Sorption, leaching, degradation, and volatilization are some of the processes being integrated through the use of simulation modeling techniques. Several research programs are focusing their attention on such issues (16, 17, 18, 32, 35), with regulatory agencies involved in management of pesticides also taking a modeling approach (3, 7). Because of the extreme complexity of agroecosystems, it is obvious that the use of simulation models will continue to be the most expeditious, reliable, and cost-effective means of integrating the various processes acting upon a pesticide to determine its fate. For example, modeling will help to summarize and interpret efficacy trials and will provide the vehicle for transferring experimental results to unstudied situations, such as the potential environmental fate of an applied herbicide. However, proper development, testing, and responsible use of a modeling approach must be based upon a thorough, comprehensive understanding of interdependent and dynamic natural processes.


Author(s):  
Syed Masud Mahmud

New types of communication networks will be necessary to meet various consumer and regulatory demands as well as satisfy requirements of safety and fuel efficiency. Various functionalities of vehicles will require various types of communication networks and networking protocols. For example, driveby- wire and active safety features will require fault tolerant networks with time-triggered protocols to guarantee deterministic latencies. Multimedia systems will require high-bandwidth networks for video transfer, and body electronics need low-bandwidth networks to keep the cost down. As the size and complexity of the network grows, the ease of integration, maintenance and troubleshooting has become a major challenge. To facilitate integration and troubleshooting of various nodes and networks, it would be desirable that networks of future vehicles should be partitioned, and the partitions should be interconnected by a hierarchical or multi-layer physical network. This book chapter describes a number of ways using which the networks of future vehicles could be designed and implemented in a cost-effective manner. The book chapter also shows how simulation models can be developed to evaluate the performance of various types of in-vehicle network topologies and select the most appropriate topology for given requirements and specifications.


2012 ◽  
Vol 52 (1) ◽  
pp. 45
Author(s):  
Elinor Alexander

Onshore Australian acreage releases and investment opportunities occurring in 2012 in Australia’s states and the Northern Territory are summarised. Diverse exploration opportunities exist for petroleum explorers in onshore basins, including potential for unconventional targets such as shale gas. The states and Northern Territory believe there are high prospects for significant new conventional and unconventional developments onshore. Australian state and territory governments continue initiatives to encourage exploration to realise their natural resource endowments. This includes pre-competitive basin studies, cost-effective and speedy provision of digital exploration data, transparent regulatory regimes, provision of effective land access regimes, internationally competitive royalty regimes, and promotion of acreage releases nationally and internationally.


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