Ground cover in temperate native perennial grass pastures. II. Relationship with herbage and litter mass

2002 ◽  
Vol 24 (2) ◽  
pp. 301 ◽  
Author(s):  
G. M. Lodge ◽  
S. R. Murphy
Keyword(s):  
Total Mass ◽  
Perennial Grass ◽  
Ground Cover ◽  
Ground Level ◽  
Perennial Grasses ◽  
Litter Mass ◽  
The Mean ◽  
Native Pastures ◽  
The Individual ◽  
The Relationship

Studies were conducted to examine the relationship between ground cover and herbage mass; ground cover and litter mass; herbage mass and litter mass, and, ground cover and total (herbage and litter) mass for two grazed, native pastures in the high rainfall, temperate rangelands of northern NSW. Ground cover was visually estimated by two experienced observers, litter (unattached plant material) was collected and herbage mass was estimated by harvesting to ground level in 30 quadrats (40 by 40 cm). Data were collected for 16 sampling times at the change of season and from spring 1997 to spring 2000 (a total of 465 quadrats at each site) and examined by regression analysis for the mean data for each level of ground cover and for data from individual quadrats. The relationship between ground cover and herbage, litter or total mass was logarithmic at each site. The logarithmic nature of the relationship reflected the occurrence of low herbage, litter and total mass even when ground cover was 100%. For the mean data, herbage and total mass accounted for 68–77% of the variation in ground cover, but for the individual quadrat data these variables accounted for 42–53% and 43–55%, respectively of this variation. Litter and herbage mass had a low correlation (R2<~0.20) and for the mean data litter mass accounted for around 40–60% of the variation in ground cover, compared with 15–21% for the individual quadrats. Some seasonal differences in these relationships were apparent and these were attributed to the occurrence of annual forb and legume species that had different growth habits to those of the native perennial grasses. For these pastures the data indicated that herbage mass could not be used as a surrogate measure of ground cover or litter mass.

Studies of competition between Nassella trichotoma (Nees) Hack. ex Arechav. (serrated tussock) and native pastures. 2. Seedling responses

2008 ◽  
Vol 59 (3) ◽  
pp. 237 ◽  
Author(s):  
W. B. Badgery ◽  
D. R. Kemp ◽  
D. L. Michalk ◽  
W. McG. King
Keyword(s):  
Dry Matter ◽  
Seedling Recruitment ◽  
Perennial Grass ◽  
Ground Cover ◽  
Perennial Grasses ◽  
Native Grass ◽  
Eastern Australia ◽  
Native Pastures ◽  
Grass Weed ◽  
Native Perennial Grass

Native perennial grass competition can substantially reduce the invasion of Nassella trichotoma (serrated tussock), a major perennial grass weed problem in south-eastern Australia. This paper reports on a field experiment that investigated the recruitment of N. trichotoma seedlings, and determined what level of native grass competition was needed to prevent establishment in the central-west of NSW. Grasslands that maintained >2 t dry matter (DM)/ha and 100% ground cover (measured in spring) prevented N. trichotoma seedling recruitment. Relatively small amounts of perennial grass (>0.5 t DM/ha measured in spring) resulted in mortality of N. trichotoma seedlings that had recruited earlier in the year, through the next summer. Flupropanate also markedly reduced native perennial grasses and substantially increased N. trichotoma seedling establishment 12 months after application. Rotational grazing to maintain adequate levels of DM was an important management tactic that prevented N. trichotoma establishment and survival.

Satellite derived maps of pasture growth status: association of classification with botanical composition

1997 ◽  
Vol 37 (5) ◽  
pp. 547 ◽  
Author(s):  
P. J. Vickery ◽  
M. J. Hill ◽  
G. E. Donald
Keyword(s):  
Near Infrared ◽  
Perennial Grass ◽  
Vegetation Indices ◽  
Fast Growth ◽  
Perennial Grasses ◽  
Bayesian Probability ◽  
Cumulative Probability ◽  
Botanical Composition ◽  
South Wales ◽  
Native Pastures

Summary. Spectral data from the green, red and near-infrared bands of Landsat MSS and Landsat TM satellite imagery acquired in mid-spring were classified into 3 and 6 pasture growth classes respectively. The classifications were compared with a site database of botanical composition for the Northern Tablelands of New South Wales to examine the association between spectral growth class and pasture composition. Pastures ranged in composition from unimproved native perennial grasses through semi-improved mixtures of native and naturalised grasses and legumes to highly improved temperate perennial grasses and legumes. For 3 years of MSS data, the fast growth class had a mean botanical composition of about 80% improved perennial grass and 0% native; medium growth class averaged 46% improved perennial grass and 14% native; while the slow growth class had about 60% native and 1% improved perennial grass when averaged over 3 years of MSS data. For the 6 class TM data from a single year, a predictive logistic regression of cumulative probability was developed for percentage of ‘very fast’ growth pixels and ordered 10 percentile categories of improved perennial grass or native grass. Differences in patch characteristics between classes with MSS disappeared with TM reclassified to the same 3 class level. Most probable pasture type was inferred from 3 class MSS and TM data using Bayesian probability analysis. The resulting maps were similar in general appearance but detail was better with the TM data. The pasture growth classification identified highly improved perennial grass pastures and native pastures but sensitivity to intermediate pasture types was poor. Future improvement will come from direct measurement of biophysical characteristics using vegetation indices or inversion of reflectance models.

Study of Speed-Flow Relationships on Individual Freeway Lanes

1997 ◽  
Vol 1591 (1) ◽  
pp. 7-13 ◽  
Author(s):  
V. F. Hurdle ◽  
Mark I. Merlo ◽  
Doug Robertson
Keyword(s):  
Practical Interest ◽  
Linear Functions ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
Speed Flow ◽  
High Flows ◽  
The Mean ◽  
The Individual ◽  
The Relationship ◽  
Very High

Many researchers have examined the form of the relationship between speed and flow on freeways. However, these researchers have concentrated on relationships for the freeway as a whole instead of on individual lanes. In this study, the relationship was examined for each of the three lanes at two locations on Highway 401 in metropolitan Toronto. It proved possible to accurately describe the mean speed in each lane with simple linear functions over the range of flows of most practical interest. Cubic functions provided comparable results over a wider range of flows, but it appears unlikely that the very high and very low flows are of sufficient interest to justify the added complexity. When an attempt was made to examine the relationship between speed and flow for the entire roadway, the linear functions were not adequate, but cubic functions performed reasonably well. However, the details of the full roadway curves are quite different from those of the curves described in the 1994 Highway Capacity Manual. In particular, the curves described in the manual are much steeper than the Highway 401 curves at high flows, implying a much more rapid loss of performance as flow approaches capacity than was observed. The full roadway curves are also surprisingly different from the curves for the individual lanes.

Soil temperatures and seed burial in relation to the performance of Heteropogon contortus and Themeda australis in burnt native woodland pastures in Eastern Queensland

1969 ◽  
Vol 17 (2) ◽  
pp. 269 ◽  
Author(s):  
JC Tothill
Keyword(s):  
Ground Cover ◽  
Ground Level ◽  
Maximum Temperature ◽  
Seed Burial ◽  
Ambient Temperatures ◽  
Seasonally Dry ◽  
Heteropogon Contortus ◽  
Average Maximum ◽  
Soil Temperatures ◽  
Native Pastures

The factors underlying the increasing dominance of Heteropogon contortus (bunch or black spear grass) as a result of regularly burning native pastures in eastern Queensland have been investigated. In the subtropical environment of this experiment the removal of ground cover by burning or other means significantly increased the average maximum temperature of the surface soil. Burning favoured the germination of buried H. contortus seed at a time when ambient temperatures were too low for this to occur in unburnt situations. In late seasons and in the seasonally dry tropics insufficient soil moisture would tend to limit growth and germination until ambient temperatures are high, in which case the burning effect would be less pronounced. The efficient seed burial mechanism of H. contortus places it at an establishment advantage over other commonly associated species such as blue grasses (Bothriochloa, Dichanthium) and others whose seeds remain largely in the surface litter. Fire destroys much of this litter, the microhabitat for seed germination at ground level, and some of the weaker perennial plants. The implications of these results in relation to the increased dominance of either H. contortus or Themeda australis (kangaroo grass) are discussed.

Monitoring Training Volume Through Maximal Number of Repetitions or Velocity-Based Approach

2020 ◽  
pp. 1-8
Author(s):  
Miguel Sánchez-Moreno ◽  
Gonçalo Rendeiro-Pinho ◽  
Pedro V. Mil-Homens ◽  
Fernando Pareja-Blanco
Keyword(s):  
Coefficient Of Variation ◽  
Bench Press ◽  
Interindividual Variability ◽  
Load Condition ◽  
Velocity Relationship ◽  
The Mean ◽  
Monitoring Training ◽  
The Individual ◽  
The Relationship ◽  
Level Of Effort

Purpose: This study aimed (1) to analyze the interindividual variability in the maximal number of repetitions (MNR) performed against a given relative load (percentage of 1-repetition maximum [%1RM]) and (2) to examine the relationship between the velocity loss (VL) magnitude and the percentage of completed repetitions with regard to the MNR (%Rep), when the %1RM is based on individual load–velocity relationships. Methods: Following an assessment of 1RM strength and individual load–velocity relationships, 14 resistance-trained men completed 5 MNR tests against loads of 50%, 60%, 70%, 80%, and 90% 1RM in the Smith machine bench-press exercise. The relative loads were determined from the individual load–velocity relationship. Results: Individual relationships between load and velocity displayed coefficients of determination (R2) ranging from .986 to .998. The MNR showed an interindividual coefficient of variation ranging from 8.6% to 33.1%, increasing as the %1RM increased. The relationship between %Rep and the magnitude of VL showed a general R2 of .92 to .94 between 50% and 80% 1RM, which decreased to .80 for 90% 1RM. The mean individual R2 values were between .97 and .99 for all loading conditions. The %Rep when a given percentage of VL was reached showed interindividual coefficient of variation values ranging from 5% to 20%, decreasing as the %Rep increased in each load condition. Conclusions: Setting a number of repetitions had acceptable interindividual variability, with moderate relative loads being adjusted based on the individual load–velocity relationship. However, to provide a more homogeneous level of effort between athletes, the VL approach should be considered, mainly when using individual VL–%Rep relationships.

A Behavioral Process Approach to Information Acquisition in Nondurable Purchasing

1978 ◽  
Vol 15 (4) ◽  
pp. 532-544 ◽  
Author(s):  
Jacob Jacoby ◽  
Robert W. Chestnut ◽  
William A. Fisher
Keyword(s):  
Information Search ◽  
Information Acquisition ◽  
Consumer Information ◽  
Behavioral Process ◽  
The Mean ◽  
The Individual ◽  
Attitudinal Brand Loyalty ◽  
Available Information ◽  
Relationship Of ◽  
The Relationship

A behavioral process method was used to explore the relationship of individual difference factors to consumer information acquisition behavior. Findings included: (1) the mean proportion of available information actually acquired was 2%, and (2) information search was concentrated on six of the 35 available information dimensions; increased information acquisition was related (3) positively to the product's importance for the individual, (4) positively to being an optimizer rather than a satisficer, (5) positively to high amounts of past purchasing experience with the product, and (6) negatively to attitudinal brand loyalty.

scholarly journals Caregiver distress associated with behavioral and psychological symptoms in mild Alzheimer's disease

2010 ◽  
Vol 4 (3) ◽  
pp. 238-244 ◽  
Author(s):  
Ari Pedro Balieiro Jr. ◽  
Emmanuelle Silva Tavares Sobreira ◽  
Marina Ceres Silva Pena ◽  
José Humberto Silva-Filho ◽  
Francisco de Assis Carvalho do Vale
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Psychological Symptoms ◽  
Time Behavior ◽  
Caregiver Distress ◽  
Night Time ◽  
The Mean ◽  
The Individual ◽  
The Relationship ◽  
Behavioral And Psychological Symptoms

Abstract The aim of this study was to analyze the relationship between Caregiver Distress and Behavioral and Psychological Symptoms in Dementias (BPSD) in mild Alzheimer's disease. Methods: Fifty patients and caregivers were interviewed using the Neuropsychiatric Inventory (NPI). Results: 96.0% of the patients had at least one BPSD. The mean NPI total score was 19.6 (SD=18.05; range=0-78) whereas the mean Caregiver Distress Index (CDI) total score was 11.5 (SD=10.41; range=0-40). For the individual symptoms, the weighted mean CDI was 2.8 (SD=1.58). All symptom CDI means were higher than 2.0 except for euphoria/elation (m=1.8; SD=1.49). There were correlations between CDI and derived measures (Frequency, Severity, FxS, and Amplitude) for all symptoms, except Disinhibition and Night-time behavior. Correlations ranged between 0.443 and 0.894, with significance at p<0.05. Conclusions: All the derived measures, including amplitude, were useful in at least some cases. The data suggests that CDI cannot be inferred from symptom presence or profile. Symptoms should be systematically investigated.

Relationship between Rated Degree of Familiarity with Individual Sentences and the Extent of Recall of Connected Discourse

1966 ◽  
Vol 19 (3_suppl) ◽  
pp. 1195-1202 ◽  
Author(s):  
John A. Mills ◽  
Alan Nicolas-Fanourakis
Keyword(s):  
Rating Scale ◽  
Interference Theory ◽  
Connected Discourse ◽  
Wide Range ◽  
The Mean ◽  
The Individual ◽  
The Relationship

An assessment was made of the strength and direction of the relationship between rated degree of familiarity for connected discourse and the extent of recall of such material. The experimental material consisted of two short passages of prose (a narrative and an argument) and of a rating scale containing all the sentences from these passages inserted randomly among other individual sentences selected from a wide range of sources. 20 Ss provided both recall scores for the passages (which were presented whole) and familiarity ratings for the sentences in the rating scale. When recall scores for the individual sentences were correlated with the mean ratings, a positive and significant value was found. The bearing of this finding on (he expectations of interference theory is discussed.

How Reliable are Growth Back-Calculations Based on Otoliths?

1990 ◽  
Vol 47 (11) ◽  
pp. 2219-2227 ◽  
Author(s):  
Steven E. Campana
Keyword(s):  
Somatic Growth ◽  
Growth Effect ◽  
Fish Otolith ◽  
Stochastic Error ◽  
Individual Fish ◽  
Back Calculation ◽  
The Mean ◽  
The Individual ◽  
The Relationship ◽  
Slow Growing

Growth back-calculations from otoliths assume that the relationship between fish and otolith length is linear through time. The final (or observed) individual fish-otolith ratios are then combined to prepare a fish-otolith regression for the population, upon which the subsequent back-calculations are based. However, recent studies have demonstrated that the fish:otolith size ratio varies systematically with somatic growth rate, resulting in relatively large otoliths in slow-growing fish. Such a growth effect will result in a fitted fish-otolith regression which differs significantly from that of the mean of the individual fish-otolith slopes. Fraser–Lee growth back-calculations made from such a regression consistently underestimate previous lengths at age. The bias may explain the apparent ubiquity of Lee's phenomenon. Back-calculation bias was eliminated through use of an algorithm defining individual fish-otolith trajectories and a biologically determined, rather than a statistically estimated, intercept. Adaptations of the biological intercept back-calculations procedure accurately predicted previous lengths in the presence of both stochastic error and time-varying growth rates. When used to reevaluate some published back-calculations, the biological intercept procedure resulted in more accurate values than those previously estimated, and reduced or eliminated the presence of Lee's phenomenon.

scholarly journals Personality and Motivation: A Correlation study among Sports Person

2019 ◽  
Vol 6 (4) ◽  
pp. 5-13
Author(s):  
M Keerthika ◽  
S Punithavathi
Keyword(s):  
Standard Deviation ◽  
Gender Difference ◽  
Correlation Coefficient ◽  
Significant Relationship ◽  
Correlation Study ◽  
Motivation Factors ◽  
The Mean ◽  
The Individual ◽  
Age Range ◽  
The Relationship

In this competitive world, it is essential to grab the sportive nature of sports persons. For different personality type of the individual the motive to engage in sports also varies from person to person. The aim of the present study is to determine the relationship between personality and motivation among sports persons and to identify the gender difference of personality and motivation factors. The sample of this study was 120 sports persons out of which 60 were males and 60 were females belonging to the age range of 18 -30 years. The mean, standard deviation and Pearson’s correlation coefficient were used for analysing the data. Results indicate that there is no significant relationship between Personality and Motivation type of sports persons.

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