Body lengths and maximum gut food-particle sizes of the dominant cladocerans and calanoid copepods in Wallerawang Reservoir, New South Wales

1991 ◽  
Vol 42 (4) ◽  
pp. 399 ◽  
Author(s):  
T Kobayashi
Keyword(s):  
Particle Size ◽  
Competitive Ability ◽  
New South ◽  
Particle Sizes ◽  
Calanoid Copepods ◽  
Food Particle ◽  
South Wales ◽  
Cladoceran Species ◽  
Body Sizes ◽  
Food Particles

Body length influences the maximum gut food-particle size of the dominant cladocerans and calanoid copepods in Wallerawang Reservoir. For the Wallerawang cladocerans, a linear regression equation, similar to the Northern Hemisphere equivalent, relates food-particle and body sizes. The larger cladoceran species ingest larger food particles than do the smaller species they displace, thus seemingly supporting the size-efficiency hypothesis. On the other hand, the competitive ability of the Wallerawang calanoid copepods cannot be explained simply by the observed differences in the upper food-particle size limit of these species.

Comparative responses of Lolium perenne and Bothriochloa macra to temperature, moisture, fertility and defoliation

1976 ◽  
Vol 27 (6) ◽  
pp. 769 ◽  
Author(s):  
SJ Cook ◽  
A Lazenby ◽  
GJ Blair
Keyword(s):  
Lolium Perenne ◽  
Competitive Ability ◽  
New South ◽  
Moisture Stress ◽  
Low Fertility ◽  
High Fertility ◽  
South Wales ◽  
Temperature Regimes ◽  
Low Levels ◽  
Moisture Conditions

Lolium perenne and Bothtriochloa macra were grown alone and In 1/1 mixtures In pot culture under molsture stress and moisture non-limiting conditions at both high and low levels of fertility, they were grown In three controlled environment cabinets operating at either 16/10°, 23/17° or 31/25°C, and defoliated to either 1 cm or 4 cm from the crown at each of two harvests.Temperature was the dormant factor differentiating the growth and competitive ability of both species Lolium grew best In the 16/10° and 23/17°C temperature regimes, production declining at 31/25° In contrast, Bothriochloa made very little growth a1 16/10° and responded linearly to measuring temperature. Both species responded similarly to increasing fertility and favourable moisture conditions, although such treatments had no effect on Bothriocochloa in the 16/10°C temperature regime Bothtriochloa was more tolerant of low fertility and moisture stress than was Loliurn, especially at 31/25° Lolium yielded more, and competed successfully with Bothtriochloa, only under conditions of high fertility and In the absence of moisture stress at temperatures up to 23/17°C Defoliation intensity had little effect on the total dry matter yields of either species, although it did influence the proportion of leaf to head and stem of Bothtriochloa. The likely implications of the results on the competitive relationships of the two species In the field In the Northern Tablelands environment of New South Wales are discussed

Seedbed requirements for Dolichos lablab

1972 ◽  
Vol 12 (56) ◽  
pp. 288
Author(s):  
GJ Murtagh
Keyword(s):  
Competitive Ability ◽  
Prime Factor ◽  
New South ◽  
Nitrogen Supply ◽  
North Coast ◽  
Dolichos Lablab ◽  
The North ◽  
South Wales ◽  
Seedbed Preparation ◽  
Grass Growth

Several methods of seedbed preparation were compared for sowing Dolichos Lablab into paspalum dominant pastures on the North Coast of New South Wales. Competition from grass reduced the growth of dolichos seedlings. Dolichos yields were highest when cultivation reduced grass growth by at least 70 per cent, or when the seedbed was sprayed with 10 kg acid equivalent 2,2-DPA per hectare. The results suggested that lack of effective nodulation when seed was inoculated with Rhizobium strain CB 454 or NA 106 was a prime factor in the low competitive ability of dolichos seedlings. It is concluded that cultivation is the better method of reducing grass competition because it also causes mineralization of soil nitrogen. This ensures an adequate nitrogen supply even if inoculation fails.

Surface structure in gray clays of northwestern New South Wales in relation to micromorphology, cation suite and particle size attributes

Soil Research ◽  
1992 ◽  
Vol 30 (1) ◽  
pp. 1 ◽  
Author(s):  
IP Little ◽  
AJ Ringrose-Voase ◽  
WT Ward
Keyword(s):  
Particle Size ◽  
Surface Structure ◽  
New South ◽  
Clay Mineralogy ◽  
Clay Content ◽  
Structural Behaviour ◽  
South Wales ◽  
Field Assessment ◽  
Structured Soils ◽  
Textural Attributes

Considerable differences in surface structure (0-100 mm) were observed in the field in two adjacent areas of grey clays near Narrabri, N.S.W. The absence of any differences in clay mineralogy and granulometry of the sand fraction supported the field assessment that both types of soil were similar in provenance. A transect of soil profiles including seven with poor structure and five with well-structured surface horizons was examined. The field observations of structure were supported by photographs of the surface, and water entry after rain. Micromorphological examination showed that closely spaced porphyric to adporphyric fabric in the poorly structured soils contributed to poor structure, highlighting the importance of textural attributes. The well-structured soils had a more widely spaced porphyric fabric. A measure of dispersibility depending on clay content and exchangeable plus soluble Na, Ca and Mg tallied very well with the field assessment of soil structure. Five groups were obtained from a euclidean distance/flexible sort strategy on the basis of cation suite, carbon content and particle size attributes. The groups identified areas of poor structure very well and the groups appear to be discriminated mainly on the basis of differences in Na, Ca and clay content. Treating the transect as a continuum of soils of very poor structure at site 1 grading to very good at site 12 showed that greater values for Ca, K, and clay were associated with good structure and greater values for Mg, C and silt were associated with poor structure. The sodium adsorption ratio and ionic strength of the soil solution were not on their own good predictors of structural behaviour possibly due to the independent contribution of Ca and Mg in this respect.

The pedogenesis of desert loam soils in the Barrier Range, western New South Wales. I. Soil parent materials

Soil Research ◽  
1982 ◽  
Vol 20 (4) ◽  
pp. 269 ◽  
Author(s):  
C.J. Chartres
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Saline Lake ◽  
New South ◽  
Morphological Properties ◽  
Parent Materials ◽  
Rock Types ◽  
Aeolian Deposits ◽  
South Wales ◽  
Mineral Assemblages

The particle-size distribution, silt (63-20 �m) mineralogy and micro-morphological properties of three desert loam soils developed over contrasting rock types are examined. The silt mineral assemblages in the soils contain more weatherable minerals and are more varied than those of the underlying rocks. Round to subround clayey pellets constitute the majority of the soil materials. Such pellets are probably aeolian in origin and are similar to clayey pellets originating in dried-out, saline lake beds elsewhere in southern Australia. The combination of aeolian silts and clays in the desert loam soils indicate that the soil parent materials are primarily transported aeolian deposits.

Relationship between Oral Sensitivity and Masticatory Performance

2004 ◽  
Vol 83 (5) ◽  
pp. 388-392 ◽  
Author(s):  
L. Engelen ◽  
A. van der Bilt ◽  
F. Bosman
Keyword(s):  
Particle Size ◽  
Topical Anesthesia ◽  
Size Perception ◽  
Light Touch ◽  
Food Particle ◽  
Masticatory Performance ◽  
Particle Size Reduction ◽  
Spatial Sensitivity ◽  
Food Particles ◽  
Oral Sensitivity

The size of a bolus determines how it will be manipulated in the mouth and swallowed. We hypothesized that mucosal sensitivity would be important for masticatory function. The accuracy of solid object size perception, spatial acuity, and food particle size reduction during mastication were measured in 22 healthy adults with/without topical anesthesia of their oral mucosa. Topical anesthesia had no effect on the perception of sphere sizes, but significantly reduced spatial sensitivity. Without anesthesia, there was a correlation between an individual’s ability to perceive the sizes of steel spheres (diameter, 4–9 mm) and the sizes of food particles chewed for 15 cycles and at swallowing. There was no correlation between spatial sensitivity and food particle size. We suggest that the stimuli used to test two-point discrimination stimulates only superficial receptors, which involve light touch and are easily anesthetized, while the spheres might excite more deeply-set receptors. The latter appear to be more important for masticatory performance and swallowing.

Latitude and elevation as factors controlling occurrence of calanoid copepods in marginal lotic waters in New South Wales, Australia

2018 ◽  
Vol 33 (6) ◽  
pp. 1103-1111 ◽  
Author(s):  
Tsuyoshi Kobayashi ◽  
Jan Miller ◽  
Ian A. E. Bayly ◽  
Cheryl Tang ◽  
Simon J. Hunter ◽  
...  
Keyword(s):  
New South ◽  
New South Wales ◽  
Calanoid Copepods ◽  
South Wales ◽  
Lotic Waters

Chemical and zooplankton studies of lentic habitats in north-eastern New South Wales

1970 ◽  
Vol 21 (1) ◽  
pp. 11 ◽  
Author(s):  
BV Timms
Keyword(s):  
New South ◽  
New South Wales ◽  
Common Species ◽  
Chloride Ions ◽  
North Coast ◽  
Calanoid Copepods ◽  
Related Factors ◽  
South Wales ◽  
North Eastern ◽  
Sodium Magnesium

Chemical and zooplankton data for 103 reservoirs and lakes on the northern tablelands and the central and north coast regions of New South Wales are presented and discussed. Twenty-three of the localities are natural, occur in five distinct regions, and are variable in their modes of origin. All the waters are fresh, and most have less than 200 p.p.m. total dissolved solids. In general, waters on the coastal plain are dominated by sodium and chloride ions, while those on the highlands are dominated by bicarbonate and sodium, magnesium, or calcium. A total of 43 species of Entomostraca inhabit the lentic environments of the area, though many of these cannot be considered to be eulimnetic species. Only a few species (2.2 copepods and 1.1 cladocerans, on the average) occur in any one locality, this number being influenced by site size and age. The distribution pattern of the major species are depicted and discussed in terms of four factors. Altitudinal-related factors are important for many species, particularly calanoid copepods; water chemistry influences the distribution of at least two species-Boeckella triarticulata (Thomson) and Calamoecia tasmanica (Smith); turbidity has a subsidiary effect on the occurrence of species in the genera Daphnia and Ceriodaphnia; and the locality age is important for most species. The relative dispersal powers of the more common species are assessed from their tendency to be present or absent in new reservoirs.

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