Change in range condition with distance from watering point and its implications for field survey.

1980 ◽  
Vol 2 (1) ◽  
pp. 59 ◽  
Author(s):  
BD Foran
Keyword(s):  
Field Survey ◽  
Reasonable Accuracy ◽  
Grid Pattern ◽  
Range Condition ◽  
Water Point ◽  
The Mean ◽  
Central Australia ◽  
Open Woodland

The effect of distance from a water point on range condition was examined for two rangeland types in central Australia; an open woodland community and a mulga annual community. Range condition was measured on a systematic grid pattern around the bore using the STARC method. In open woodland, range condition improved at about 2 km from water, but in mulga annual no change was detected due partly to a low number of sites close to the bore. The location of sampling sites adjacent to station roads did introduce some bias vrhen compared to the mean score over the whole area. The amount of bias acceptable must be seen in relation to factors such as time available for survey and the ease with which sample sites can be relocated. Two to four sampling sites located at a distance greater than 2 km, in rangeland preferred by cattle gave a mean score within 30% of the true mean for the whole area with the influence of 'sacrifice area' excluded. A reasonable accuracy of range condition sampling can be achieved in extensive central Australian rangelands. by stratifying the areas sampled with respect to country preferred by cattle and distance grazed from water.

Grazing intensity of cattle on a complex of rangeland communities in Central Australia.

1980 ◽  
Vol 2 (1) ◽  
pp. 76 ◽  
Author(s):  
WA Low ◽  
WJ Muller ◽  
ML Dudzinski
Keyword(s):  
Perennial Grass ◽  
Grazing Intensity ◽  
Cattle Grazing ◽  
Annual Grass ◽  
Range Condition ◽  
Aerial Surveys ◽  
The Mean ◽  
Central Australia ◽  
Free Ranging

Distribution of cattle grazing the rangeland communities of Kunoth Paddock in central Australia was determined from aerial surveys at fortnightly intervals over a 4.5 year period. Mean density throughout the study was 3.5 cattle/km2 and varied between communities from 8.0 cattle/km2 to 0.4 cattle/km2 on the major communities and from 25.6 cattle/km2 to 3.2 cattle/km2 on the minor communities. Cow-days of use were calculated for seasonal intervals to show grazing intensity on the communities over ti~ne. Grazing concentrations throughout the study revealed three groups of utilization levels of the major communities. Foothill fans, Woodlands, Floodplains and Gilgaied plains received about twice the mean grazing intensity for the paddock. Mulga-annual grass received about average grazing intensity and Hills and Mulga-perennial grass received less than half the average grazing intensity. Our sti~dy shows that cattle graze range communities differentially in a free-ranging situation. This information is useful in interpreting results of range condition and trend studies, and also suggests that more uniform utilization of all the communities might be obtained by controlhng grazing distribution.

Habitat use and behaviour of cattle in a heterogeneous desert environment in central Australia

2012 ◽  
Vol 34 (3) ◽  
pp. 319 ◽  
Author(s):  
Anke S. K. Frank ◽  
Chris R. Dickman ◽  
Glenda M. Wardle
Keyword(s):  
Habitat Use ◽  
Arid Environments ◽  
Desert Environment ◽  
Point Location ◽  
Dune System ◽  
Grazing Impacts ◽  
Water Point ◽  
Resource Poor ◽  
Central Australia ◽  
Simpson Desert

The activities of livestock in arid environments typically centre on watering points, with grazing impacts often predicted to decrease uniformly, as radial piospheres, with distance from water. In patchy desert environments, however, the spatial distribution of grazing impacts is more difficult to predict. In this study sightings and dung transects are used to identify preferred cattle habitats in the heterogeneous dune system of the Simpson Desert, central Australia. The importance of watering points as foci for cattle activity was confirmed and it was shown that patchily distributed gidgee woodland, which comprises only 16% of the desert environment, is the most heavily used habitat for cattle away from water and provides critical forage and shade resources. By contrast, dune swales and sides, which are dominated by shade- and forage-deficient spinifex grassland and comprise >70% of the available habitat, were less utilised. These results suggest that habitat use by cattle is influenced jointly by water point location and by the dispersion of woodland patches in a resource-poor matrix. The findings were used to build a modified conceptual model of cattle habitat use which was compared with an original piosphere model, and the consequences for wildlife in environments where the model applies are discussed.

Duplex ultrasound interpretation criteria for inferior mesenteric arteries

Vascular ◽  
2012 ◽  
Vol 20 (3) ◽  
pp. 145-149 ◽  
Author(s):  
Ali F AbuRahma ◽  
L Scott Dean
Keyword(s):  
Mesenteric Artery ◽  
Inferior Mesenteric Artery ◽  
Duplex Ultrasound ◽  
Mesenteric Arteries ◽  
Reasonable Accuracy ◽  
Diastolic Velocity ◽  
Interpretation Criteria ◽  
The Mean ◽  
Better Than ◽  
Mesenteric Arteriography

There is no specific duplex ultrasound (DUS) criteria for the diagnosis of inferior mesenteric artery (IMA) stenosis. This study will define the optimal duplex velocity values with the best overall accuracy (OA) in detecting ≥50% stenosis of the IMAs. Eighty-five IMAs with both DUS and mesenteric arteriography were analyzed. Eighty-five IMAs were examined: 45 were normal, 12 with <50% stenosis, eight with ≥50–69% stenosis and 15 with ≥70% stenosis (including occlusion) based on angiography. The mean peak systolic velocities (PSVs) for a normal IMA, <50% and ≥50% stenosis was 105, 215 and 392 cm/second, respectively ( P < 0.0001). The most accurate PSV in detecting ≥50% stenosis was ≥250 cm/second with a sensitivity of 90%, a specificity of 96% and an OA of 95%. The most accurate end-diastolic velocity (EDV) in detecting ≥50% stenosis was ≥80% or ≥90 cm/second, with an OA of 86%, a sensitivity of 60% and a specificity of 100%. The most accurate ratio in detecting ≥50% stenosis was ≥4 or ≥4.5 with an OA of 93%.Receiver operator curves analysis showed that the PSV was not better than EDV and PSV ratio in detecting ≥50% stenosis ( P = 0.1661 and 0.4568, respectively). In conclusion, specific IMA PSVs, EDVs and IMA/aortic systolic ratios can be used in detecting significant IMA stenosis with reasonable accuracy.

The population structure and density of central Australian trees and shrubs, and relationships to range condition, rabbit abundance and soil.

1985 ◽  
Vol 7 (2) ◽  
pp. 130 ◽  
Author(s):  
MH Friedel
Keyword(s):  
Population Structure ◽  
Woody Plant ◽  
Fire Regimes ◽  
Population Characteristics ◽  
Plant Resource ◽  
Range Condition ◽  
Term Change ◽  
Open Woodland ◽  
Trees And Shrubs

The regional variation in population structure and density of trees and shrubs was investigated in four central Australian pasture types: open woodland, mulga annual, calcareous shrubby grassland and bluebush nse. The possible influences of range condition, rabbit abundance, soil erosion and so11 characteristics were examined, and the likelihood of long-term change was cons~dered. Density at some woodland and mulga sites was potentially high enough to depress pasture yield. The most common "increaser"species were Casszaspp. in open woodland and mulga (Acaciaaneura) in mulga annual. None of the measured influences related closely to population structure and density, and it is argued that changed fire regimes are most likely to have led to increasing densities of trees and shrubs. Density in calcareous shrubby grasslands was related to rabbit abundance, and smaller size classes of trees and shrubs were severely depleted whererab- bits were plentiful. Continuing loss of the woody plant resource is forecast, if rabbits are not controlled. Other measured influences were not related to woody plant population characteristics. Bluebush (Maireana miroiricha) populations were considered to be relatively stable under current management of bluebush rises.

scholarly journals Neochrysocharis okazakii(Hymenoptera: Eulophidae) as a Major Parasitoid Wasp of Stone Leek Leaf MinerLiriomyza chinensis(Diptera: Agromyzidae) in Central Vietnam

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Takatoshi Ueno ◽  
Dang Hoa Tran
Keyword(s):  
Field Survey ◽  
Host Density ◽  
Parasitoid Wasp ◽  
Leaf Miner ◽  
Welsh Onion ◽  
Leaf Miners ◽  
Central Vietnam ◽  
Major Pest ◽  
The Mean ◽  
Parasitoid Aggregation

Liriomyza chinensisis a major pest of Welsh onionAllium fistulosumin Asia but little is known about the abundance of its natural enemies. A field survey was made to explore the major parasitoids ofL. chinensisleaf miner in central Vietnam. An eulophid parasitoid,Neochrysocharis okazakii,comprised more than 95% of parasitoids reared from leaf miner larvae collected in the onion field and 98.3% of leaf miner parasitoids found during searches of onion plants. The mean number of femaleN. okazakiion plants was greater in onion fields with a higher density ofL. chinensis, and, during searches, a greater proportion ofN. okazakiiwas found on onion with moreL. chinensismines, suggesting density-dependent parasitoid aggregation. Melanized dead larvae ofL. chinensiswere more frequently found in onion fields with more parasitoids, demonstrating that melanized leaf miners are a good indicator of parasitoid activity. Mean instant rate of host encounter byN. okazakiiin the field was estimated at 0.077, and the likelihood of a parasitoid finding a host increased with host density. Taken together, these results show thatN. okazakiiis the major parasitoid ofL. chinensis. Usefulness of this parasitoid in stone leek leaf miner management is discussed.

Development of a 2D+T theory for performance prediction of double-stepped planing hulls in calm water

2018 ◽  
Vol 233 (3) ◽  
pp. 886-904 ◽  
Author(s):  
Rasul Niazmand Bilandi ◽  
Abbas Dashtimanesh ◽  
Sasan Tavakoli
Keyword(s):  
Mathematical Model ◽  
Performance Prediction ◽  
Empirical Models ◽  
Two Dimensional ◽  
Reasonable Accuracy ◽  
Future Studies ◽  
Normal Forces ◽  
Calm Water ◽  
The Mean ◽  
The Mathematical Model

In this article, a mathematical model based on the 2D+T theory has been developed to predict the performance of two-stepped planing hulls in calm water. It has been attempted to develop a mathematical model without using regression formulas. It leads to development of a computational model with no common limitations related to empirical models which have an individual range of applicability. For this purpose, theoretical solution of water entry of a two-dimensional wedge section has been implemented to compute the pressure distribution over wedge section entering water, and then normal forces acting on the two-dimensional sections are computed. Bottom of the boat has been divided into three different planing surfaces including fore, middle and aft bodies. Computations are performed for each of these surfaces. By integrating the two-dimensional sectional normal forces over the entire wetted length of the vessel, the trim angle, wetted surface and resistance have been obtained. To evaluate the accuracy of the presented method, the obtained results are compared against experimental data and a previous empirical-based method developed by authors. The comparison suggests that the proposed method predicted dynamic trim angle, wetted surface and resistance of double stepped boats with reasonable accuracy. The mean errors in prediction of trim angle, wetted surface and resistance are, respectively, 13%, 16% and 8%. It should also be noted that although computation of running attitudes and resistance of double-stepped planing boats are targeted in this article, the mathematical model has been developed in such a way that it has the potential to model transverse and vertical motions of two-stepped planing hulls in future studies.

Corrigendum - Water consumption by lucerne in central Australia

1960 ◽  
Vol 11 (5) ◽  
pp. 715
Author(s):  
EA Jackson
Keyword(s):  
Soil Water ◽  
Water Consumption ◽  
Water Loss ◽  
Growth Stages ◽  
The Mean ◽  
Central Australia ◽  
The Relationship ◽  
Water Contents ◽  
Soil Water Contents

Observations on the loss of water from soil under irrigated lucerne have been made over a 12 month period at Alice Springs. The relationship between this water loss and tank evaporation has been determined and used to calculate mean monthly requirements of lucerne in this environment. The mean annual requirement is 90 in. Data are also presented showing the rate of water loss at different soil water contents, growth stages of the crop, and soil depths.

Evaluation of International Normalized Ratios by a Controlled Field Survey with 4 Different Thromboplastin Reagents

1990 ◽  
Vol 64 (04) ◽  
pp. 535-541 ◽  
Author(s):  
Mutsuyoshi Kazama ◽  
Setsuko Suzuki ◽  
Takeshi Abe ◽  
Chieko Tahara ◽  
Chisato Shimazu ◽  
...  
Keyword(s):  
Prothrombin Time ◽  
Field Survey ◽  
Nationwide Survey ◽  
The Other ◽  
Comparison Of Methods ◽  
Prothrombin Activity ◽  
Mean Values ◽  
Plot Analysis ◽  
The Mean ◽  
Whisker Plot

SummaryA nationwide survey has been performed in Japan involving 75 laboratories to assess the relative reliability of different methods of reporting prothrombin time results in anticoagulant control. The interchangeability of results using prothrombin time, prothrombin activity percentage, prothrombin ratio and international normalized ratios (INR) were compared with four different thromboplastin reagents and a range of coagulometers. A secondary batch of reference thromboplastin of human brain origin (BCT/454) was used to calibrate the local thromboplastins and for comparison of methods of reporting. The study revealed the closest agreement of the results between BCT and the other reagents, and the regression lines of these reagents were almost identical, when the results were reported as INR. Box-Whisker plot analysis showed that the distribution of the results was large with the more deficient plasmas with all methods of reporting. It was found by this analysis that the interchangeability of the results was greatest when the results were expressed by INR, because the mean values obtained of each plasma using different thromboplastin reagents gave the lowest CV and the frequency of the far-out data was least, compared with the other methods of expression. On the other hand, the type of coagulometer had almost as much effect as the thromboplastin reagent on the prothrombin time, even if INR was used. Interchangeability of INR would be further improved by providing ISI values for each reagent/ instrument combination.

scholarly journals An alternative method for measuring velocities in open-channel flows: perfomance evaluation of a Pitot tube compared to an acoustic meter

RBRH ◽  
2017 ◽  
Vol 22 (0) ◽  
Author(s):  
Arlan Scortegagna Almeida ◽  
Vladimir Caramori Borges de Souza
Keyword(s):  
Open Channel ◽  
Channel Flows ◽  
Pitot Tube ◽  
Reasonable Accuracy ◽  
Open Channel Flows ◽  
Velocity Fluctuations ◽  
Alternative Method ◽  
Total Head ◽  
Order Of Magnitude ◽  
The Mean

ABSTRACT Hydrometric measurements undertaken in channels with high velocities are conditioned to the particularities of the flow, which is often characterized by instantaneous fluctuations and disturbances on the free surface. In such cases, the uncertainties associated with velocity fluctuations exceed the precision offered by the instruments that are employed in conventional techniques. A reasonable accuracy of the results is therefore sufficient to accomplish the objective of the measurements. The use of devices based on Pitot’s principle in fast open-channel flows could be an effective alternative to conventional velocity meters. This study aimed to develop a Pitot tube in its simplest configuration and evaluate its performance in a laboratory channel at velocities ranging from 0.2 to 2.0 m/s. The uncertainties in the static and total head readings were propagated to the output velocities, showing that the device built has the potential for measurements over 1.2 m/s, but it is not recommended for low velocities (<0.6 m/s). The results were compared to those taken using an Acoustic Doppler Velocimeter (ADV). The instantaneous velocity readings indicated uncertainties of the same order of magnitude in both instruments. The differences between the mean velocities measured by the Pitot tube and the ADV were restricted to an agreement range of 15%, which is expected to be gradually reduced with further increase in flow velocity. The results showed the similar performances of both devices regarding the higher velocity estimates. Therefore, velocity meters should be developed to employ Pitot devices as an alternative method in high-velocity open-channel flows.

scholarly journals Combining UAV Imagery, Volunteered Geographic Information, and Field Survey Data to Improve Characterization of Rural Water Points in Malawi

2020 ◽  
Vol 9 (10) ◽  
pp. 592
Author(s):  
Marc van den Homberg ◽  
Arjen Crince ◽  
Jurg Wilbrink ◽  
Daniël Kersbergen ◽  
Gumbi Gumbi ◽  
...  
Keyword(s):  
Survey Data ◽  
Satellite Imagery ◽  
Field Survey ◽  
Cost Effective ◽  
Volunteered Geographic Information ◽  
Geographic Information ◽  
Small Data ◽  
Small Areas ◽  
Water Point ◽  
Combining Data

As the world is digitizing fast, the increase in Big and Small Data offers opportunities to enrich official statistics for reporting on Sustainable Development Goals (SDG). However, survey data coming from an increased number of organizations (Small Data) and Big Data offer challenges in terms of data heterogeneity. This paper describes a methodology for combining various data sources to create a more comprehensive dataset on SDG 6.1.1. (proportion of population using safely managed drinking water services). We enabled digital volunteers to trace buildings on satellite imagery and used the traces on OpenStreetMap to facilitate visual detection of water points on Unmanned Aerial Vehicle (UAV) imagery and estimate the number of people served per water point. Combining data on water points identified on our UAV imagery with data on water points from field surveys improves the overall quality in terms of removal of inconsistencies and enrichment of attribute information. Satellite imagery enables scaling more easily than UAV imagery but is too costly to acquire at sufficiently high resolution. For small areas, our workflow is cost-effective in creating an up-to-date and consistent water point dataset by combining UAV imagery, Volunteered Geographic Information, and field survey data.

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