Phytophthora cinnamomi in native vegetation in South Australia.

1977 ◽  
Vol 6 (2) ◽  
pp. 22 ◽  
Author(s):  
TC Lee ◽  
TJ Wicks
1994 ◽  
Vol 34 (1) ◽  
pp. 741 ◽  
Author(s):  
M. L. Williams ◽  
A. J. Boulton ◽  
M. Hyde ◽  
A. J. Kinnear ◽  
C. D. Cockshell

The Department of Mines and Energy, South Australia (DME) contracted Michael Williams and Associates Pty Ltd to audit the environmental management of seismic exploration operations in the South Australian Otway Basin. The audit was carried out in early 1992 and covered petroleum exploration operators and DME environmental management systems. An innovative field sampling technique was developed to compare the environmental impact of two different seismic line clearing techniques. Recovery of native vegetation as measured by vegetation structure was also quantified.The audit found DME to have a dynamic and integrated environmental management system while company systems varied in standard. Wide consultation assisted the audit process.As a result of clearing for agriculture, native vegetation covers only six per cent of the Otway Basin. With the strict limitations to broad-scale vegetation clearance since the mid-1980s and the cessation since 1991, the greatest environmental impact of seismic exploration is the clearance of native vegetation for access by seismic vehicles. Native vegetation structure and associated abiotic variables on seismic lines and adjacent control sites, were subject to a classification and ordination analysis which compared the impact of seismic lines constructed by bulldozer or Hydro-ax (industrial slasher). Post-seismic recovery rates of three different vegetation associations were also determined. This analytical technique permits the effects of seismic line clearance to be compared with the natural variability of specific vegetation associations within a region. In interpreting the results however, there is a confounding effect of line type and year as most of the more recent seismic lines were constructed using a Hydro-ax. Results indicate that Hydro-ax clearing affects vegetation structure less than bulldozing. Most Hydro-ax sites recovered within a few years whereas some sites, bulldozed as early as 1971, particularly tussock grasslands, have not yet recovered.This study provides a significant break-through in the debate about the persistence of seismic impacts on native vegetation. As a rapid preliminary assessment, sampling vegetation structure rather than floristics, provides a cost-effective audit and monitoring technique which can be used by non-specialists in a range of petroleum exploration environments. Any significant structural differences may require more detailed analysis to determine if floristic composition also differed.


Nematologica ◽  
1981 ◽  
Vol 27 (3) ◽  
pp. 319-329 ◽  
Author(s):  
Francoise Reay ◽  
H.R. Wallace

1981 ◽  
Vol 29 (1) ◽  
pp. 11 ◽  
Author(s):  
M Bumbieris

In a pine forest plantation, P. cinnamomi was rarely isolated from the root zones, and never from the roots, of established P. radiata growing at P. cinnamomi sites. When a P. cinnamomi site was replanted with P. radiata, a third of the young pines died during the first 9 months, about 50% of them yielding P. cinnamomi from roots. Death of the trees followed an increase in the soil population density of P. cinnamomi which appeared to be correlated with increasing soil temp. and high soil moisture.


Author(s):  

Abstract A new distribution map is provided for Phytophthora cinnamomi Rands. Hosts: Ananas, Cinchona, Cinnamomum, Castanea, Persea, Pinus, Rhododendron and others. Information is given on the geographical distribution in Africa, Burundi, Cameroon, Congo, Gabon, Guinea, Ivory Coast, Kenya, Morocco, South Africa, Uganda, Zambia, Zimbabwe, Asia, China, Jiangsu, India, Madras, Andhra, Pradesh, West Bengal, Indonesia, Java, Sumatra, Israel, Japan, Malaysia, Peninsular, Sabah, Philippines, Taiwan, Turkey, Vietnam, USSR, Georgia, Australasia & Oceania, Australia, New South Wales, Queensland, Victoria, Western Australia, South Australia, Tasmania, Northern Territory, Cook Island, Fiji, Hawaii, New Zealand, Okinawa, Papua New Guinea, Sumatra, Europe, Azores, Belgium, France, Corsica, Germany, Irish Republic, Italy, Netherlands, Portugal, Spain, Switzerland, UK, USSR, Black Sea Region, Yugoslavia, North America, Canada, British Columbia, Mexico, USA, Central America & West Indies, Barbados, Belize, Costa Rica, Cuba, Dominican Republic, Guatemala, Honduras, Jamaica, Panama, Puerto Rico, Salvador, St Lucia, St Vincent, Trinidad, South America, Argentina, Bolivia, Brazil, Sao Paulo, Brasilia, Chile, Colombia, Guyana, Peru, Venezuela.


2005 ◽  
Vol 53 (5) ◽  
pp. 455 ◽  
Author(s):  
Sophie Petit ◽  
Catherine Ruth Dickson

We examined the role of the grass-tree Xanthorrhoea semiplana F.Muell. canopy in the survival of the nationally endangered orchid Caladenia (syn. Arachnorchis) behrii Schltdl. at three sites in the northern Adelaide region. We compared grazing and pollination of the flowering orchids within and away from the grass-tree canopy. Grass-trees generally provided significant protection from grazing, but orchids protected by grass-trees experienced reduced pollination for 2 out of 5 years. The net effect of these interactions, as measured by seed set, varied across years. When grazing pressure is high, orchids may benefit from grass-tree protection (facilitation), but under low grazing pressure, it is more probable that orchids set seeds away from grass-trees than under their canopy. Grazing pressure probably does not decrease in view of habitat fragmentation the importance of fragments as wildlife refuges. Therefore, factors affecting the survival of grass-trees, such as Phytophthora cinnamomi, may also affect orchid survival. Kangaroos which are often assumed to be responsible for most grazing in the Adelaide Hills are not the only predators of orchids, and a culling program has so far not resulted in a decrease of grazing pressure for the orchids. Translocation and fencing programs should examine the role of facilitative plants and grazers before spending precious conservation resources.


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