The impact of rabbits on a grazing system in eastern New South Wales.1. Ground cover and pastures

2002 ◽  
Vol 42 (7) ◽  
pp. 909 ◽  
Author(s):  
J. D. Croft ◽  
P. J. S. Fleming ◽  
R. van de Ven

Although there have been a number of studies that have examined the effects of rabbits on pasture, the relationship between rabbit density and pasture degradation caused by rabbits has never been quantified. An experiment was conducted at Cowra, New South Wales, from October 1984 to October 1987, to determine the impact various densities of rabbits have on pasture composition, indices of pasture biomass and ground cover. Using plots set stocked with the equivalent of 8 sheep/ha (the district average) and 4 densities of rabbits as treatments, 0,�24, 48 and 72 rabbits/ha, the consequences of rabbit grazing were investigated.Pasture composition changed with season, year and rabbit density. Cumulative effects were also evident. Rabbits severely depleted improved pastures of legumes (subterranean clover particularly), with grass cover increasing proportionate to rabbit density. In the final year of the experiment, the rabbit-free treatment had 31% legumes and 25.2% grasses, whereas the highest rabbit density treatment had 6.2% legumes and 47.4% grasses. Indices of pasture biomass were highest in the zero rabbits/ha treatment and lowest in the 72 rabbits/ha treatment. More bare soil was exposed in the highest rabbit density treatment. Once seasonal and year effects were accounted for, the relationship between rabbit density and percentage damage was positive.

1987 ◽  
Vol 27 (6) ◽  
pp. 791 ◽  
Author(s):  
KA Archer ◽  
EC Wolfe ◽  
BR Cullis

The period from sowing to flowering was determined for 8 subterranean clover cultivars sown in late March, late April and late May at 9 environmentally distinct locations in New South Wales. The length of the period to flowering depended on cultivar (ranging from a mean of 1 12 days for Northam to 151 days for Larisa) and site (from a mean of 1 18 days at Grafton to 145 days at Canberra). There was a greater range in the period from sowing to flowering between cultivars at earlier flowering sites compared with late flowering sites. The period from sowing to flowering decreased with later sowings so that clovers sown late (May) flowered on average less than 14 days after those sown early (March). A relationship was developed between temperature and latitude and the period to flowering for each sowing date and cultivar. This relationship accounted for 95% of the variation in flowering time observed in this study and was used to predict with acceptable accuracy the flowering time of subterranean clover cultivars in a study undertaken in Western Australia in 1972 and 1973. We believe the relationship could be useful in predicting flowering time in subterranean clovers.


2004 ◽  
Vol 44 (6) ◽  
pp. 571 ◽  
Author(s):  
S. R. Murphy ◽  
G. M. Lodge ◽  
S. Harden

Evapotranspiration is the major component of the hydrological balance of grazed pastures on the North-West Slopes of New South Wales, representing up to 93% of annual rainfall. Nearly 80% of evapotranspiration may occur as bare soil evaporation, however, representing water not available for plant growth. Few studies have reported daily values of actual evapotranspiration for pastures, particularly in northern New South Wales. The studies reported here were conducted to measure actual evapotranspiration using an evaporation dome technique, for plots with a range of pasture, litter and ground cover. Measurements were taken in each season between autumn 2000 and autumn 2001, with both wet and dry soil surface conditions, to document the range of values that might be expected. Similar measurements were conducted in areas of natural pasture, to quantify values under grazed conditions. A range of other variables were also quantified in association with each evapotranspiration measurement; these included components of net radiant energy, atmospheric conditions, pasture physical characteristics, ground cover and soil water content. These data were used to identify the most important variables, which may be influenced by or interact with grazing management, that account for variation in daily evapotranspiration values.Hourly evapotranspiration ranged from 0.02 to 0.82 mm/h and daily values ranged from 0.2 to 7.6 mm/day, in winter to summer, respectively. Linear regression models that included variables of solar radiation, herbage mass, vapour pressure deficit and soil water content accounted for up to 93% of the variation in daily evapotranspiration values. These models predicted that high litter mass (3000 kg DM/ha) may reduce evaporation by up to 1 mm/day for wet soils, making a substantial contribution to the annual hydrological balance. A simulation study of a grazed pasture, using the Sustainable Grazing Systems Pasture Model, indicated that grazing management may influence the partitioning of transpiration and evaporation from canopy, litter and bare soil. With rotational grazing, predicted soil evaporation was lower and transpiration and canopy evaporation were higher than with continuous grazing. Hence, pastures may require different management between summer and winter, so that bare soil evaporation and canopy interception losses are minimised, to maximise stored soil water available for pasture use. Pastures with lower evaporative losses are likely to have higher productivity and sustainability.


1996 ◽  
Vol 36 (3) ◽  
pp. 299 ◽  
Author(s):  
TS Andrews ◽  
RDB Whalley ◽  
CE Jones

Inputs and losses from Giant Parramatta grass [GPG, Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens] soil seed banks were quantified on the North Coast of New South Wales. Monthly potential seed production and actual seed fall was estimated at Valla during 1991-92. Total potential production was >668 000 seeds/m2 for the season, while seed fall was >146000 seeds/m2. Seed fall >10000 seeds/m2.month was recorded from January until May, with further seed falls recorded in June and July. The impact of seed production on seed banks was assessed by estimating seed banks in the seed production quadrats before and after seed fall. Seed banks in 4 of the 6 sites decreased in year 2, although seed numbers at 1 damp site increased markedly. Defoliation from mid-December until February, April or June prevented seed production, reducing seed banks by 34% over 7 months. Seed banks in undefoliated plots increased by 3300 seeds/m2, although seed fall was estimated at >114 000 seeds/m2. Emergence of GPG seedlings from artificially established and naturally occurring, persistent seed banks was recorded for 3 years from bare and vegetated treatment plots. Sown seeds showed high levels of innate dormancy and only 4% of seeds emerged when sown immediately after collection. Longer storage of seeds after collection resulted in more seedlings emerging. Estimates of persistent seed banks ranged from 1650 to about 21260 seeds/m2. Most seedlings emerged in spring or autumn and this was correlated with rainfall but not with ambient temperatures. Rates of seed bank decline in both bare and vegetated treatment plots was estimated by fitting exponential decay curves to seed bank estimates. Assuming no further seed inputs, it was estimated that it would take about 3 and 5 years, respectively, for seed banks to decline to 150 seeds/m2 in bare and vegetated treatments.


1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.


1995 ◽  
Vol 37 (2) ◽  
pp. 203-217 ◽  
Author(s):  
Michael O'Donnell

Decentralizing industrial relations within New South Wales is a central recom mendation of the Niland Green Paper (1989). Decentralism also represents the cornerstone of the New South Wales government's industrial relations reform agenda enshrined in the New South Wales Industrial Relations Act 1991. To date there has been little analysis of the impact o f this legislative change on industrial relations in the New South Wales public sector. This paper provides a case study that examines the degree to which responsibility for bargaining has been devolved within the Parks and Gardens of the New South Wales Ministry for the Environ ment. It argues that, in contrast to the rhetoric of the New South Wales Act, the central agency presiding over the introduction of enterprise bargaining in the public sector, the Public Employment and Industrial Relations Authority; has been reluctant to delegate responsibility to parties in the workplace.


2021 ◽  
Vol 55 (1) ◽  
pp. 84-94
Author(s):  
Andrea Wallace ◽  
Brian Dollery

Abstract In response to the COVID-19 pandemic, the New South Wales (NSW) government ordered the closure of all municipal libraries in order to limit the impact of the contagion. As a result, 372 public libraries in NSW ceased operation on the 23rd March 2020. While the closure of public libraries will undoubtedly contribute to restricting the spread of the coronavirus, given the pivotal role played by municipal libraries in local communities, as well as the special characteristics of library patrons, it will have other negative consequences. In this paper we consider the impact of the closure of municipal libraries in NSW from two perspectives: (a) its effect on the fiscal circumstances of local authorities and (b) its impact on the spread of the corona contagion as well as its broader effects on local community wellbeing. We conclude that rather than complete closure, partial constraints on library use should have been considered.


2021 ◽  
Author(s):  
Timothy Lahmers ◽  
Sujay Kumar ◽  
Aubrey Dugger ◽  
David Gochis ◽  
Joseph Santanello

<div> <p>In late 2019 widespread wildfires impacted much of the New South Wales province in south east Australia, and this loss of vegetation contributed to increased surface runoff and consequently major flooding caused by extreme rainfall by early 2020. The recently developed NASA LIS/WRF-Hydro system enables the data assimilation (DA) capabilities of the NASA Land Information System (LIS) and the surface hydrological modeling capabilities of the WRF-Hydro model to be combined in a single model architecture. Combining the DA capabilities of the LIS system with WRF-Hydro, which has been used for both research and operational hydrologic simulations, we investigate the impacts of vegetation DA on the simulated floods in several basins across New South Wales, with varying degrees of burn severity from the 2019 fires. We also consider the impacts of the wildfires, as realized through vegetation DA on water partitioning and the surface energy budget, which both have implications for L-A interactions. For DA, we utilize the leaf area index retrievals from MODIS and vegetation optical depth from SMAP. For the present study, we will quantify the impact of the changes to the landscape brought about by the wildfires on hydrologic response, including flood severity, which would not be possible without the DA capabilities of the LIS/WRF-Hydro system.</p> </div>


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