Daily changes in plant water content in western Queensland: implications for red kangaroo foraging times

2004 ◽  
Vol 26 (1) ◽  
pp. 102 ◽  
Author(s):  
S. Underhill ◽  
G. C. Grigg ◽  
D. J. Yates
Keyword(s):  
Water Content ◽  
National Park ◽  
Plant Water ◽  
Forage Plants ◽  
Red Kangaroo ◽  
Macropus Rufus ◽  
Daily Changes ◽  
Semi Arid

We measured daily changes in plant water content to see if red kangaroos (Macropus rufus), in foraging at night, may gain more water than foraging by day. If so, it could be influential in dictating their time of foraging. The study was stimulated by work in Africa which showed that, by choosing to feed at night, gazelles are able to take advantage of increased plant water content. Daily changes in water content of 15 known forage plants were examined at Idalia National Park in semi-arid western Queensland in February, April and July 2002, during progressive drying of the country in an extraordinarily dry year. Of 29 day-night comparisons of plant water content, thirteen showed no difference, two (both of red spinach, Trianthema triquetra) showed a substantial increase at night, eight showed small but statistically significant increases, and six showed small but statistically significant decreases. We conclude that the choice of red kangaroos to forage at night is unlikely to be explained by nightly increases in plant water content.

Habitat Selection by Sex, Age and Reproductive Class in the Red Kangaroo, Macropus rufus, in Western New South Wales

1981 ◽  
Vol 8 (3) ◽  
pp. 465 ◽  
Author(s):  
CN Johnson ◽  
PG Bayliss
Keyword(s):  
Habitat Selection ◽  
National Park ◽  
Mating Systems ◽  
New South ◽  
New South Wales ◽  
Vegetation Types ◽  
Red Kangaroo ◽  
South Wales ◽  
Macropus Rufus ◽  
Lactating Females

The kangaroo populations of Kinchega National Park respond differently to shifts in pasture productivity, red kangaroos Macropus rufus being mobile and unevenly distributed with respect to soil and vegetation types, by comparison with the more evenly dispersed western grey kangaroos M. fuliginosus and the sedentary and localized euros M, robustus erubescens. Red kangaroo population classes tend to be differentially distributed, so that large males and heavily lactating females predominate on the seasonally preferred pastures, while other classes tend to predominate elsewhere. This finding has several implications for the management of red kangaroos and for our understanding of their resource ecology and mating systems.

The Method of Plant Water Status Measurement in Sweet Potato (Ipomoea Batatas (L) Lam.)

2010 ◽  
Vol 7 (1) ◽  
Author(s):  
Saraswati Prabawardani
Keyword(s):  
Water Content ◽  
Sweet Potato ◽  
Relative Water Content ◽  
Water Status ◽  
Plant Water Status ◽  
Equilibration Time ◽  
Plant Water ◽  
Font Size ◽  
Potato Leaf ◽  
Relative Water

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scholarly journals Modelling the Impact on Root Water Uptake and Solute Return Flow of Different Drip Irrigation Regimes with Brackish Water

Water ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 425 ◽  
Author(s):  
Fairouz Slama ◽  
Nessrine Zemni ◽  
Fethi Bouksila ◽  
Roberto De Mascellis ◽  
Rachida Bouhlila
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Soil Water Content ◽  
Water Uptake ◽  
Brackish Water ◽  
Deficit Irrigation ◽  
Root Zone ◽  
Root Water Uptake ◽  
Return Flows ◽  
Semi Arid

Water scarcity and quality degradation represent real threats to economic, social, and environmental development of arid and semi-arid regions. Drip irrigation associated to Deficit Irrigation (DI) has been investigated as a water saving technique. Yet its environmental impacts on soil and groundwater need to be gone into in depth especially when using brackish irrigation water. Soil water content and salinity were monitored in a fully drip irrigated potato plot with brackish water (4.45 dSm−1) in semi-arid Tunisia. The HYDRUS-1D model was used to investigate the effects of different irrigation regimes (deficit irrigation (T1R, 70% ETc), full irrigation (T2R, 100% ETc), and farmer’s schedule (T3R, 237% ETc) on root water uptake, root zone salinity, and solute return flows to groundwater. The simulated values of soil water content (θ) and electrical conductivity of soil solution (ECsw) were in good agreement with the observation values, as indicated by mean RMSE values (≤0.008 m3·m−3, and ≤0.28 dSm−1 for soil water content and ECsw respectively). The results of the different simulation treatments showed that relative yield accounted for 54%, 70%, and 85.5% of the potential maximal value when both water and solute stress were considered for deficit, full. and farmer’s irrigation, respectively. Root zone salinity was the lowest and root water uptake was the same with and without solute stress for the treatment corresponding to the farmer’s irrigation schedule (273% ETc). Solute return flows reaching the groundwater were the highest for T3R after two subsequent rainfall seasons. Beyond the water efficiency of DI with brackish water, long term studies need to focus on its impact on soil and groundwater salinization risks under changing climate conditions.

Changing perceptions of the effect of plant phenolics on nutrient supply in the ruminant

1996 ◽  
Vol 47 (6) ◽  
pp. 829 ◽  
Author(s):  
JB Lowry ◽  
CS McSweeney ◽  
B Palmer
Keyword(s):  
Phenolic Compounds ◽  
Acute Toxicity ◽  
Protein Interactions ◽  
Nutrient Supply ◽  
Arid Environments ◽  
Plant Phenolics ◽  
Ruminant Nutrition ◽  
Forage Plants ◽  
Hydrolysable Tannins ◽  
Semi Arid

Mammalian metabolism of plant phenolics, initially studied in monogastric animals, gave an emphasis to their toxic and antinutrient effects. Subsequent studies in tropical ruminants and wild herbivores have highlighted the high levels than can occur in some diets and the extensive microbial modification and degradation that can occur in the tract. This paper reviews aspects of plant phenolics as they relate to ruminant nutrition in tropical or semi-arid environments in which some forage plants contain high levels of phenolic compounds. Effects range from occasional acute toxicity of hydrolysable tannins, to acetate-releasing microbial degradations that apparently enable certain phenolics to act as nutrients. The most important and complex effects are those due to tannin-protein interactions. Although these can clearly reduce feed intake, nutrient digestibilities, and protein availability, many of the interactions are still not understood. The diverse effects of plant phenolics on nutrient flow probably result from the balance between adverse effects on some organisms and the rate at which they are degraded or inactivated by other organisms, and improved animal performance can likely be obtained by manipulation of rumen microbial metabolism.

Diagnosis and treatment of mesenteric volvulus in a red kangaroo (Macropus rufus)

2014 ◽  
Vol 244 (7) ◽  
pp. 844-850 ◽  
Author(s):  
S. Emmanuelle Knafo ◽  
Alana J. Rosenblatt ◽  
James K. Morrisey ◽  
James A. Flanders ◽  
Margret S. Thompson ◽  
...  
Keyword(s):  
Diagnosis And Treatment ◽  
Red Kangaroo ◽  
Macropus Rufus
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