A u s t r a L i a n n e t w o r k f o r p L a n t c o n s e r V a t I o n


Chemical and biochemical properties of the soil as tools for monitoring



Yüklə 0.56 Mb.
Pdf просмотр
səhifə3/7
tarix24.08.2017
ölçüsü0.56 Mb.
1   2   3   4   5   6   7

Chemical and biochemical properties of the soil as tools for monitoring 

woodland degradation and restoration 

Katarzyna Bialkowski 

Murdoch University, South Street, Murdoch WA 6150 

Forest certification is encouraging Australian plantation companies to manage biodiversity within their 

estates. This generally requires protecting and managing the native forest and woodland remnants as 

they provide important habitat for fauna and flora in a plantation landscape. However, many remnants 

have been degraded by soil nutrient enrichment and weed invasion, and so support less native 

biodiversity. We investigated the suitability of a range of chemical and biological measures to monitor 

the condition of the soil in woodland remnants so that the degradation process, as well as the 

effectiveness of restoration treatments, could be quantitatively assessed. The remnants were within 

Eucalyptus globulus plantations from south western Western Australia. Small-scale, short-term trials 

were conducted:  clearing, artificial fertilisation and assisting weed invasion were used in the 

degradation trial; herbicides (glyphosate and simazine) and mulching with plantation harvest residue 

were used in the restoration trial. Soil potassium, ammonium and nitrate content, basal respiration and 

β- glucosidase activity showed potential to detect changes in soils caused by these treatments. Effects 

were evaluated by comparison with reference sites: intact native woodland (undisturbed reference) and 

pasture (disturbed reference). Fertilisation, both alone and with grass invasion, but not clearing or grass 

alone, had negative effects on soil properties after only a few months in a degradation trial. Glyphosate, 

but not mulching, significantly improved the condition of the soil in restoration trial. We demonstrated 

that the combination of a few chemical and biological soil properties can be used for quantitative and 

sensitive monitoring of the in condition native woodland remnants. 

Adaptive genetic diversity among Tuart (Eucalyptus gomphocephala

populations and implications for ecological restoration 

Donna Bradbury

1,2

, Siegy Krauss

1,2

, Ann Smithson

1,2 

and Erik Veneklaas

1,3

 

1. School of Plant Biology, The University of Western Australia 

2. Botanic Gardens & Parks Authority, Fraser Avenue, West Perth WA 6005.  

3. Centre of Excellence for Climate Change, Woodland and Forest Health 

Tuart (Eucalyptus gomphocephala) is a forest and woodland tree that occurs exclusively on the Swan 

Coastal Plain of Western Australia. Tuart communities are of high ecological and conservation value, but 

widespread canopy decline and clearing has required significant restoration efforts. Tuart populations 

only mass-flower every 5-8 years, which makes local collection of ample seeds difficult year after year. It 

has been advocated that, rather than a strict maintenance of local provenance, seeds should be 

collected more widely to increase genetic diversity, equipping populations with the variation to adapt to 

environmental change. While this may avoid some problems associated with exclusive local provenance 

collections, it is known that neutral genetic markers are not adequate predictors of ‘adaptability’ because 

they do not occur in functional genes. 

For this reason, we have developed functional genetic markers for Eucalyptus (EST-SSRs) that are 

homologous with candidate genes for flowering, pathogen defence and other processes that are likely to 

be important for adaptation to environmental change. These functional markers, as well as neutral 

markers, are being screened among natural populations to detect functional versus neutral Tuart 

population genetic structure and diversity. We are coupling this research with a field-based reciprocal 

transplant trial, which after one year has not revealed significant local adaptation for seed emergence, 

seedling survival or growth among six Tuart provenances. Visual condition scores, however, have 

indicated that northern provenances were less stressed following summer than southern provenances. 

Implications of these results for seed collection and Tuart restoration will be discussed. 



Do genetic bottlenecks occur during the restoration process?  

Linda Broadhurst  

CSIRO Plant Industry PO Box 1600, Canberra ACT 2601, Email: Linda.Broadhurst@csiro.au  

Restoring landscapes with high quality, genetically diverse seed is critical for ensuring that these new 

populations have the genetic arsenal required to meet the challenges of rapidly changing environments. 



        18  

 

Australian Network for Plant Conservation 8



th

 National Conference

 

Several stages during the restoration process have the potential to inadvertently create genetic 



bottlenecks and produce poor biodiversity outcomes. For example, collecting and deploying seed with a 

low genetic base may lead to inbreeding and poor quality seed. Space and resource limitation in a 

production nursery may also reduce levels of genetic diversity available for planting which in the longer 

term, as these seedlings become reproductive adults, may be even further eroded by mate-limitation 

and increased selfing. Under these circumstances the long term persistence of these populations is 

likely to be limited. Each of these possible scenarios was investigated in yellow box (Eucalyptus 



melliodora), a key restoration species that has been extensively cleared across south eastern Australia. 

Data regarding the genetic diversity in seed collections, seedlings grown through a production nursery, 

and that being produced by restored populations will be presented and discussed.  

Managing Geraldton Carnation Weed (Euphorbia terracina), in the 

woodlands, wetlands and heathlands of the Swan Coastal Plain 

Kate Brown, Julia Cullity, Grazyna Paczkowska and Karen Bettink,  

Department of Environment and Conservation, Swan Region, PO Box 1167, Bentley Delivery Centre WA 6983. 

Geraldton Carnation Weed (Euphorbia terracina), an invasive perennial herb, is a major threat to 

remnant woodlands, wetlands and heathlands of the Swan Coastal Plain.  A series of studies over the 

last 5 years have monitored the effectiveness of established control methods, investigated more 

effective alternatives as well as studying the resilience and recovery of invaded plant communities. Work 

has focused on sites of high conservation value where invasion by Geraldton Carnation Weed is a key 

threatening process.  

In threatened sedgelands that occur in Holocene dune swales at Point Becher near Rockingham, south 

of Perth, trials were carried out with the herbicide Logran® at 12.5g/100L. Cover of Geraldton Carnation 

Weed decreased significantly in the first year and went from an average of 19.2 % in 2005 before 

treatment, to less than 0.4% in 2008.  Concurrently there was an increase in the cover of native species 

particularly the sedge Ficinia nodosa and the rush Baumea juncea. In July 2009 similar trials were 

established in comparatively species rich coastal heathlands north of Perth and preliminary results will 

be discussed. 

Work at Paganoni Swamp has focused on monitoring the effectiveness of established control methods 

to prevent spread of Geraldton Carnation Weed into one of the most significant conservation reserves in 

the metropolitan region south of the Swan River. The 700 hectare site protects a mosaic of Tuart 

/Banksia Woodlands and low-lying wetlands. The results of this work will be presented. 

In addition to these studies, as part of a strategic management approach, a regional plan focusing on 

gaining an understanding of the distribution of Geraldton Carnation Weed and protecting key biodiversity 

sites from invasion has been produced. 



Working with community groups to conserve threatened orchids in the 

WA wheatbelt  

Mark Brundrett 

University of Western Australia, Crawley WA 6009 

The Wheatbelt Orchid Rescue (WOR) project is a Lotterywest funded collaboration between the WA 

Native Orchid Study and Conservation Group (WANOSCG), the WA Department of Environment and 

Conservation, the Friends of Kings Park and the University of Western Australia. This project is helping 

to conserve endangered orchids in the WA wheatbelt by obtaining knowledge required for sustainable 

management and directly contributing to recovery actions. Surveys utilizing WANOSCG members 

provided accurate population and habitat size data for the Granite Spider, Ballerina, William’s Spider, 

Lonely Hammer and Underground Orchids (Caladenia graniticola, C. melanema, C. williamsiae, 

Drakaea isolata, Rhizanthella gardneri). Permanent transects measured annual fluctuations in emergent 

orchids and threats to populations. Numbers of plants that emerge and flower varied substantially from 

year to year, as rates of pollination (0-85%) and grazing (5-50%) varied with species and habitat. Key 

threats to these orchids include very small habitat areas, herbivory, infrequent pollination and salinity. 

Knowledge gained is being used to update recovery plans and guide conservation actions.  

Seed baiting experiments, where orchid seeds germinate over soil organic matter, identified potential 

orchid habitats and investigated the role of mycorrhizal fungi. Research in terrestrial orchid seed 

germination resulted in a new method for non-sterile seedling production that was more rapid and 

efficient than germination in sterile culture. “Translocation pouches” were designed to protect tiny 


   

 

 



 

19 


 Australian Network for Plant Conservation 8

th

 National Conference



 

seedlings during acclimation in the incubator nursery or field. It is anticipated that more efficient 

production of orchid seedlings will facilitate translocation programs for endangered species and result in 

a better understanding of orchid seedling growth and nutrition. Translocation trials with seedlings of rare 

and common orchids are underway. 

Biotechnology and conservation of critically endangered plants in a 

biodiverse region – the south west of Western Australia 

Eric Bunn 

Botanic Gardens & Parks Authority, Fraser Avenue, West Perth WA 6005  

The unique flora of the South West Australian Floristic Region (SWAFR) - a recognized world plant 

biodiversity hotspot - with over 7000 indigenous taxa and high endemism (~ 50 %) has undergone 

considerable anthropogenic alteration of the landscape post-European settlement. Extensive clearing for 

agriculture, weed and feral animal incursions in the SWAFR have impacted severely on natural 

ecosystem services and most declared endangered flora (DRF) are from this region. Of a total of some 

2,800 Western Australian species requiring conservation over 400 DRF are gazetted for Western 

Australia, of which approximately 120 are critically endangered (CR). Climatic change (including 

decreasing rainfall) is already impacting on the SWAFR incurring additional stresses on a region already 

under pressure. Biotechnology is playing a key role in the fight to save endangered species threatened 

with imminent extinction. Conservation research can draw on molecular, in vitro and cryogenic 

technologies to achieve this. In emergency situations remaining individual plants of endangered species 

can be micropropagated and maintained ex situ permanently in culture collections and/or cryopreserved. 

Genetic fingerprinting technology can be harnessed to identify key genotypes for in vitro 

culture/cryopreservation that can ensure sufficient genetic representation for restoration sites and also 

provide early warning of inbreeding depression among offspring in repatriated populations. Bridging 

between biotechnology and conservation has the potential to save many critically endangered plants in 

a biodiverse region such as the SWAFR, as has been demonstrated with a number of CR taxa to date. 

Weighing up the numbers: case studies in the use of numerical taxonomy 

for resolving conservation-listed taxa in south-west Western Australia 

Ryonen Butcher, Rob Davis, Neil Gibson and Juliet Wege 

Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre WA 6983 

The South-West Australian Floristic Region (SWAFR) is renowned for its floral biodiversity and the high 

degree of endemism of its species, many of which have evolved relatively recently. Just over 8,000 

native plant taxa occur in the SWAFR, approximately 24% of which are conservation-listed. 

Approximately 14% of these conservation-listed taxa have not yet been formally described and named, 

with the majority lacking descriptive and ecological information essential for their management. 

While some informally-named taxa are relatively distinctive, many fall within difficult complexes where 

taxonomic boundaries are defined by subtle differences in morphology or unique combinations of 

characters, and are obscured by continuous or overlapping measurement values and intra-taxon 

polymorphism. Where the intricate associations between taxa are difficult to unravel using traditional 

taxonomic approaches, numerical taxonomy can be employed to objectively assess the utility of 

characters for defining and discriminating taxa, and to identify groups of samples which may be discrete 

entities. Numerical taxonomic methods range from simple analyses of variance in key characters within 

and between taxa through to multivariate morphometric analyses, where cluster analysis and ordination 

can be used to reduce complex patterns of morphological variation within and between taxa into more 

easily interpretable graphical representations of similarity. 

This talk will provide an overview of how numerical taxonomy (especially morphometric analysis) has 

been employed within the Western Australian Herbarium for investigating putatively new, or poorly 

defined, conservation taxa in Marianthus (Pittosporaceae), Ptilotus (Amaranthaceae), Synaphea 

(Proteaceae) and Tetratheca (Elaeocarpaceae). The conservation outcomes of each study will be 

discussed. 



        20  

 

Australian Network for Plant Conservation 8



th

 National Conference

 

Restoring and maintaining genetic connections in a landscape context 

Margaret Byrne, Colin Yates, David Coates, Carole Elliott, Neil Gibson, Jane Sampson and Melissa 

Millar 

Science Division, Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre WA 

6983 

Gene flow among populations is a fundamental evolutionary process for maintenance of genetic 



cohesiveness in species. Restoration programs can restore and/or maintain gene flow to ensure 

continued genetic connectivity within a species in a given landscape. Landscape design configurations 

that maximise genetic connectivity will enhance ecological process and landscape functioning thus 

contributing to persistence of populations within fragmented landscapes.  

Recent studies on pollen dispersal have demonstrated significant gene flow across the landscape for 

many species. Paternity assignment has shown that up to 65% of seed can be sired by pollen 

immigration from plants outside the population. This pollen dispersal has been recorded over distances 

of up to 5 km in south-western Australia. Pollen dispersal studies show that genetic connectivity can be 

maintained in fragmented landscapes, and that small remnant populations and paddock trees make 

important contributions to genetic connectivity. Knowledge of pollen dispersal patterns can be used in 

landscape design for configuration of populations that maximise genetic connectivity. 

Maintenance of gene flow across the landscape is an important consideration for restoration programs, 

but may not always be beneficial. Extensive pollen dispersal can be detrimental when it involves a 

source of foreign genes in the landscape, such as plantings that use non-local but related taxa. Such 

activities should be conducted within a risk management framework to ensure that these programs 

achieve rehabilitation outcomes without negative impacts on remnant patches of biodiversity.  



Defining temperature thresholds for germination: What can they tell us 

about species vulnerability to a changing climate?  

A. Cochrane  

Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre WA 6983 

Temperature is arguably one of the most important climatic variables influencing seeds and seedlings 

since it synchronises germination to environmental conditions most suitable for seedling establishment. 

Germination is an important life history phase for obligate seeding species, and failure to germinate after 

disturbance events may mean local population extinction. Seeds will germinate over a range of 

temperatures, with thresholds above and below which little or no germination will occur. Under climate 

warming scenarios temperatures are forecast to rise between 2-5

o

C.  If species have specific 



temperature requirements for germination then climate warming could cause a mismatch between 

temperatures seeds experience and temperatures over which germination is able to occur. Such a 

mismatch in the germination niche of obligate seeding species could render them vulnerable to decline 

and extinction.   

Using a temperature gradient plate more than 45 Western Australian native species were temperature 

profiled for germination. Some geographically restricted species were found to have wide thermal 

tolerance for germination, suggesting that temperature for germination is not a constraining factor to 

population persistence or possible range extension under predicted climate warming. Such species 

appear to be pre-adapted to warmer temperatures for germination and may be less of a conservation 

concern than those with narrow thermal tolerances. This novel seed-based predictive tool should help 

improve management efficiency for prioritising conservation actions, influencing choice of populations 

and sites for species reintroductions and restoration into novel environments.  



The role of fire in the persistence of threatened flora in the Western 

Australian Wheatbelt – Pityrodia scabra case study 

Joel Collins 

Department of Environment and Conservation, PO Box 332, Merredin WA 6415 

The Department of Environment and Conservation’s Central Wheatbelt District covers 21% of the 

internationally recognised South West biodiversity hotspot. The District contains 94 known threatened 

flora species which are listed as declared rare flora under the Wildlife Conservation Act 1950. Of the 

species listed as critically endangered 67% are endemic to the region. These species are highly 

localised to specific habitats and often represented by small populations that are in decline. The use of 


   

 

 



 

21 


 Australian Network for Plant Conservation 8

th

 National Conference



 

site specific recruitment burns as a recovery action has been beneficial for fire dependent species to 

regenerate and persist in the highly fragmented landscape.  

The Wyalkatchem Foxglove (Pityrodia scabra) is currently listed as critically endangered and at risk of 

extinction. Strategic burning within the populations during 2006-2010 has successfully promoted 

recruitment of seedlings that have reached reproductive maturity. The use of fire as a recruitment 

mechanism is a key component of the overall management of threatened flora in the wheatbelt.   

A Big Slice of Flora Pie, the Alinytjara Wilurara NRM Region, managing 

threatened flora across 250,000 square kilometres 

Karan Coombe-Smith 

Alinytjara Wilurara NRM Board, 321 Goodwood Road, Kings Park SA 5034 

The Alinytjara Wilurara Natural Resources Management Region covers 250,000km

2

 in arguably the 



most pristine, arid and remote landscapes of South Australia.  The region has over fifty plant species of 

national and state conservation significance.  This includes species that do not have sufficient data to be 

effectively rated, as well as species that have not had their occurrence at sites confirmed for many 

years.  The threatened flora in the region cover a range of genera and forms - orchids, forbs, daisies, 

fire-dependant legumes, chenopods, flowering bushes, mallees and aquatic plants.  And the habitats 

they occupy vary from the edge of the Nullarbor cliffs to the highest ranges in South Australia and the 

driest deserts.  But, for the region’s threatened flora species, there remain many unknowns.  The area of 

distribution, populations and total numbers are not known.  Threats have not been fully assessed.  

Levels of recruitment and survival in the face of risks such as fire, feral animals and weeds are generally 

unknown, as are the impacts likely under a changing climate. 

With limited resources the Alinytjara Wilurara NRM Board is working hard to prioritise its on-ground 

assessment and conservation activities to get the best conservation outcomes possible.  However, the 

region presents many challenges including prioritising species with limited information; logistics of 

working in a remote and arid region; taking a landscape approach to management while conserving site-

specific threatened flora; and considering the issue of refugia in a changing climate.  Truly, ‘a big slice of 

flora pie’. 



Urban landscapes supporting plant conservation 

Susan Dempster 

Everlasting Concepts, PO Box 2049, Bedford WA 6059 

Engaging with industry can provide opportunities to utilise specialist expertise and experience in 

conservation and restoration projects, and form valuable partnerships which can achieve successful 

outcomes. Whether it’s botanical consultants identifying conservation values through survey work or 

mining companies managing restored land on their leases, there are many avenues to engage industry. 

This topic seeks to discuss the challenges of identifying the ‘who, what, how, why and when’ of industry 

involvement in plant conservation. 

Community awareness of sustainability and the importance of preserving our biodiversity is driving 

change.  A questioning of the collective industries ‘modis operandi’ that identify, grow, supply, install and 

manage indigenous plants for sustainable community landscapes, identifies barriers in protecting plant 

conservation in urban developments.  

These barriers are observed from urban developments through to handover to Local Government. In 

general, current community landscapes are not suited to our environment, or sustainable.  The 

indigenous plant horticulture industry is constrained by accepted norms in various connected industries. 

The supply chain supporting the existing horticultural industry is not set up to develop and support the 

widespread uptake of indigenous plants into community and domestic landscapes.  This is in fact 

causing significant restrictions to the growth of the indigenous plant horticultural industry.  As a result, 

new community landscapes that set out to incorporate local plants, fail at a time when public demand for 

environmentally sustainable development is becoming de rigueur. 

To ensure changes and indigenous plants are embraced, the barriers need to be addressed from policy 

through to the management of landscapes and bushlands. When these barriers are embraced the urban 

development industry will be an enormous resource to assist in plant conservation and biodiversity 

protection. Achievement of this goal will improve environmental outcomes for urban development and 

connected industries to ensure local biodiversity is protected and a ‘Sense of Place’ is created. 


        22  

 

Australian Network for Plant Conservation 8



th

 National Conference

 

It is the connection of the relevant horticultural industries and the urban development industry that will 



provide significant support to sustainable plant conservation within the local municipalities. 




Поделитесь с Вашими друзьями:
1   2   3   4   5   6   7


Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur ©azkurs.org 2019
rəhbərliyinə müraciət

    Ana səhifə