Investigations into the effects of elevated carbon dioxide and drought on the growth and physiology of carpet weed (Galenia pubescens Eckl. & Zeyh.)
- Mahmood, Ako, Florentine, Singarayer, Fernando, Nimesha, Wright, Wendy, Palmer, Grant, McLaren, David, Sillitoe, Jim
- Authors: Mahmood, Ako , Florentine, Singarayer , Fernando, Nimesha , Wright, Wendy , Palmer, Grant , McLaren, David , Sillitoe, Jim
- Date: 2016
- Type: Text , Conference proceedings
- Relation: 20th Australasian Weeds Conference 2016; Perth, Western Australia; 11th-15th September 2016 p. 347-350
- Full Text:
- Reviewed:
- Description: The present study aimed to examine the interactive effects of elevated atmospheric CO2 concentration and drought stress on the growth and some of the physiological processes of Galenia pubescens. Photosynthetic rate of plants increased under elevated CO2 concentration, however drought caused significant reduction in net photosynthetic rate by (45% in 400 ppm CO2) and (27% in 700 ppm CO2) after five days simulating the drought treatment when compared with well-watered plants. Plants grown under elevated CO2 level and well-watered produced a greater biomass (17.5 ± 0.5 g per plant) compared to the plants which were grown under the ambient CO2 concentration.
- Authors: Mahmood, Ako , Florentine, Singarayer , Fernando, Nimesha , Wright, Wendy , Palmer, Grant , McLaren, David , Sillitoe, Jim
- Date: 2016
- Type: Text , Conference proceedings
- Relation: 20th Australasian Weeds Conference 2016; Perth, Western Australia; 11th-15th September 2016 p. 347-350
- Full Text:
- Reviewed:
- Description: The present study aimed to examine the interactive effects of elevated atmospheric CO2 concentration and drought stress on the growth and some of the physiological processes of Galenia pubescens. Photosynthetic rate of plants increased under elevated CO2 concentration, however drought caused significant reduction in net photosynthetic rate by (45% in 400 ppm CO2) and (27% in 700 ppm CO2) after five days simulating the drought treatment when compared with well-watered plants. Plants grown under elevated CO2 level and well-watered produced a greater biomass (17.5 ± 0.5 g per plant) compared to the plants which were grown under the ambient CO2 concentration.
- Florentine, Singarayer, Milberg, Per, Di Stefano, Julian, Westbrooke, Martin, Graz, Patrick
- Authors: Florentine, Singarayer , Milberg, Per , Di Stefano, Julian , Westbrooke, Martin , Graz, Patrick
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of Arid Environments Vol. 121, no. October (2015), p. 7-14
- Full Text:
- Reviewed:
- Description: Australian arid vegetation has evolved within highly variable environments characterised by low rainfall and sporadic fire events. Episodic high rainfall events are a significant factor in plant species recruitment, but their unpredictability makes them difficult to study. We report on the response of vascular plants to a major rainfall event and flood in an arid region of south-eastern Australia. Fire that occurred two months before the flood was incorporated into the study. Paired fenced and unfenced plots were established at control locations and also in areas that had been either flooded, burnt, or flooded and burnt. Objectives were to quantify the long-term effects of fire, flood and vertebrate herbivory, and their interactions, on vegetation composition, plant life forms and species diversity. We found that relative to controls (i) there was a significant effect of flooding on vegetation composition, (ii) changes in life form abundance were driven by flooding and grazing, (iii) there was a strong positive relationship between grazer exclusion and species diversity that was maintained over time and (iv) there was little effect of fire. Understanding the long-term effects of both natural disturbances and vertebrate herbivory will benefit plant conservation in the arid zone. © 2015 Elsevier Ltd.
Detecting the seeds of Nassella neesiana in large round hay bales, by means of non-destructive core sampling
- Weller, Sandra, Florentine, Singarayer, Sillitoe, Jim, Grech, Charles, McLaren, David, Chauhan, Bhagirath
- Authors: Weller, Sandra , Florentine, Singarayer , Sillitoe, Jim , Grech, Charles , McLaren, David , Chauhan, Bhagirath
- Date: 2015
- Type: Text , Journal article
- Relation: Plos One Vol. 10, no. 9 (2015), p.
- Full Text:
- Reviewed:
- Description: In the last three decades or so there has been a significant increase in fodder trading, both in terms of the quantity of fodder traded and in terms of its economic value to the industry. Often, this fodder type may be supplied free of charge to graziers in distress due to circumstances that follow natural disasters such as bushfires, drought, and flood. However, because of the obvious urgency arising from these situations, it is suspected that much relief fodder may unintentionally pose an elevated risk for dispersal of weeds since it may be supplied from pasture not normally used for trade in fodder, and therefore is of unknown quality. Previous destructive method to detect weed propagules in bales of fodder are cumbersome, time consuming and of limited ecological and statistical value. Therefore, objective of this paper was to development of a convenient method to assess round pasture hay bales for the presence of weed propagules, to prevent unintentional spread of noxious species in hay bales. To examine this objective known quantity of seeds were added in a series of distributions to bales of seed free pasture hay, and a positive correlation for the amount of seed added per bale with that recovered in core samples was observed. Whilst the number of seeds detected per bale varied according to the distribution of seeds within the bales and the number of cores analysed, the absolute detection of seeds suggests that this sampling method is worthy of further examination. In addition, a pragmatic estimation of bale remnants after stock feeding has been investigated to more closely estimate the potential size of the remaining seed bank. The authors propose that development of this approach is timely, in the light of future climatic uncertainty driving extreme weather events that increase the need for relief fodder, which can be a potential vector for the spread of noxious weed seeds.
- Authors: Weller, Sandra , Florentine, Singarayer , Sillitoe, Jim , Grech, Charles , McLaren, David , Chauhan, Bhagirath
- Date: 2015
- Type: Text , Journal article
- Relation: Plos One Vol. 10, no. 9 (2015), p.
- Full Text:
- Reviewed:
- Description: In the last three decades or so there has been a significant increase in fodder trading, both in terms of the quantity of fodder traded and in terms of its economic value to the industry. Often, this fodder type may be supplied free of charge to graziers in distress due to circumstances that follow natural disasters such as bushfires, drought, and flood. However, because of the obvious urgency arising from these situations, it is suspected that much relief fodder may unintentionally pose an elevated risk for dispersal of weeds since it may be supplied from pasture not normally used for trade in fodder, and therefore is of unknown quality. Previous destructive method to detect weed propagules in bales of fodder are cumbersome, time consuming and of limited ecological and statistical value. Therefore, objective of this paper was to development of a convenient method to assess round pasture hay bales for the presence of weed propagules, to prevent unintentional spread of noxious species in hay bales. To examine this objective known quantity of seeds were added in a series of distributions to bales of seed free pasture hay, and a positive correlation for the amount of seed added per bale with that recovered in core samples was observed. Whilst the number of seeds detected per bale varied according to the distribution of seeds within the bales and the number of cores analysed, the absolute detection of seeds suggests that this sampling method is worthy of further examination. In addition, a pragmatic estimation of bale remnants after stock feeding has been investigated to more closely estimate the potential size of the remaining seed bank. The authors propose that development of this approach is timely, in the light of future climatic uncertainty driving extreme weather events that increase the need for relief fodder, which can be a potential vector for the spread of noxious weed seeds.
The need for speed: Timely prevention of the dispersal of noxious weeds in relief fodder using efficient sampling procedures
- Weller, Sandra, Florentine, Singarayer, Sillitoe, Jim, Grech, Charles, McLaren, David, Chauhan, Bhagirath
- Authors: Weller, Sandra , Florentine, Singarayer , Sillitoe, Jim , Grech, Charles , McLaren, David , Chauhan, Bhagirath
- Date: 2015
- Type: Text , Journal article
- Relation: Crop Protection Vol. 70, no. (2015), p. 21-27
- Full Text:
- Reviewed:
- Description: Invasive and noxious weeds are well known as a pervasive problem, imposing significant economic burdens on all areas of agriculture. Whilst there are multiple possible pathways of weed dispersal in this industry, of particular interest to this discussion is the unintended dispersal of weed seeds within fodder. During periods of drought or following natural disasters such as wild fire or flood, there arises the urgent need for 'relief' fodder to ensure survival and recovery of livestock. In emergency situations, relief fodder may be sourced from widely dispersed geographic regions, and some of these regions may be invaded by an extensive variety of weeds that are both exotic and detrimental to the intended destination for the fodder. Pasture hay is a common source of relief fodder and it typically consists of a mixture of grassy and broadleaf species that may include noxious weeds. When required urgently, pasture hay for relief fodder can be cut, baled, and transported over long distances in a short period of time, with little opportunity for prebaling inspection. It appears that, at the present time, there has been little effort towards rapid testing of bales, post-baling, for the presence of noxious weeds, as a measure to prevent dispersal of seeds. Published studies have relied on the analysis of relatively small numbers of bales, tested to destruction, in order to reveal seed species for identification and enumeration. The development of faster, more reliable, and non-destructive sampling methods is essential to increase the fodder industry's capacity to prevent the dispersal of noxious weeds to previously unaffected locales.
- Authors: Weller, Sandra , Florentine, Singarayer , Sillitoe, Jim , Grech, Charles , McLaren, David , Chauhan, Bhagirath
- Date: 2015
- Type: Text , Journal article
- Relation: Crop Protection Vol. 70, no. (2015), p. 21-27
- Full Text:
- Reviewed:
- Description: Invasive and noxious weeds are well known as a pervasive problem, imposing significant economic burdens on all areas of agriculture. Whilst there are multiple possible pathways of weed dispersal in this industry, of particular interest to this discussion is the unintended dispersal of weed seeds within fodder. During periods of drought or following natural disasters such as wild fire or flood, there arises the urgent need for 'relief' fodder to ensure survival and recovery of livestock. In emergency situations, relief fodder may be sourced from widely dispersed geographic regions, and some of these regions may be invaded by an extensive variety of weeds that are both exotic and detrimental to the intended destination for the fodder. Pasture hay is a common source of relief fodder and it typically consists of a mixture of grassy and broadleaf species that may include noxious weeds. When required urgently, pasture hay for relief fodder can be cut, baled, and transported over long distances in a short period of time, with little opportunity for prebaling inspection. It appears that, at the present time, there has been little effort towards rapid testing of bales, post-baling, for the presence of noxious weeds, as a measure to prevent dispersal of seeds. Published studies have relied on the analysis of relatively small numbers of bales, tested to destruction, in order to reveal seed species for identification and enumeration. The development of faster, more reliable, and non-destructive sampling methods is essential to increase the fodder industry's capacity to prevent the dispersal of noxious weeds to previously unaffected locales.
Collembola (Springtails)
- Greenslade, Penelope, Florentine, Singarayer
- Authors: Greenslade, Penelope , Florentine, Singarayer
- Date: 2014
- Type: Text , Book chapter
- Relation: The distributions of invertebrate species along the Warra/Mt Weld altitudinal transect 2001/2002 and identification of taxa restricted by altitude (part of the Nature Conservation Report Series 13/4) Chapter 6 p.1-73
- Full Text:
- Reviewed:
- Description: Summary 1. The distributions of Collembola on the Warra-Mount Weld Altitudinal Transect were investigated based on samples taken from February–April 2001, November–December 2001 and January– February 2002. 2. The Collembola of the Warra-Mount Weld Altitudinal Transect was species rich with more than 40 species collected; the majority of species recorded have not been described. 3. Most of the species collected are considered endemic to Tasmania and some endemic genera were present. 4. The Malaise traps performed well indicating that a suite of species are arboreal and highly vagile. 5. No exotic (introduced, alien) species were detected in this study indicating that the area sampled has been little disturbed and is of high conservation value. 6. Altitudinal trends were evident with a small number of species only occurring at the high altitudes and others only at low altitudes. Only a few species appeared to occur at all altitudes sampled. 7. Ordination plots showed that Collembola assemblages at lower altitude sites on the Warra transect were more similar to each other than those at the higher altitude sites on Mount Weld which formed three clusters: 1100; 1200 and 1300 m; and 800, 900 and 1000 m. 8. Mount Weld sites 600 and 700 m faunas were most similar to Warra sites so forming a continuum in altitudinal zonation between Warra and Mount Weld. 9. PERMANOVA analysis of monthly pitfall catches in 2001 and 2002 showed differences between months and altitudes on both transects and that the differences between months were more distinct at the lower altitude Warra sites than on the higher altitude Mount Weld sites. This difference was particularly marked for the month of February, which was the only month surveyed in both years. 10.Much of the change in faunal assemblages along the Warra and Mount Weld altitudinal transect seemed to be the result of changes in vegetation cover. The most abrupt faunal transitions took place across the tree line between 1000 and 1100 m and a smaller change from lowland forest to subalpine woodland on the Mount Weld transect. 11.Much material in the pitfalls was in very poor condition because of the long trapping time with unsuitable preservative so could not be identified to species but rough estimates were made of numbers of individuals in each family or genus.
- Authors: Greenslade, Penelope , Florentine, Singarayer
- Date: 2014
- Type: Text , Book chapter
- Relation: The distributions of invertebrate species along the Warra/Mt Weld altitudinal transect 2001/2002 and identification of taxa restricted by altitude (part of the Nature Conservation Report Series 13/4) Chapter 6 p.1-73
- Full Text:
- Reviewed:
- Description: Summary 1. The distributions of Collembola on the Warra-Mount Weld Altitudinal Transect were investigated based on samples taken from February–April 2001, November–December 2001 and January– February 2002. 2. The Collembola of the Warra-Mount Weld Altitudinal Transect was species rich with more than 40 species collected; the majority of species recorded have not been described. 3. Most of the species collected are considered endemic to Tasmania and some endemic genera were present. 4. The Malaise traps performed well indicating that a suite of species are arboreal and highly vagile. 5. No exotic (introduced, alien) species were detected in this study indicating that the area sampled has been little disturbed and is of high conservation value. 6. Altitudinal trends were evident with a small number of species only occurring at the high altitudes and others only at low altitudes. Only a few species appeared to occur at all altitudes sampled. 7. Ordination plots showed that Collembola assemblages at lower altitude sites on the Warra transect were more similar to each other than those at the higher altitude sites on Mount Weld which formed three clusters: 1100; 1200 and 1300 m; and 800, 900 and 1000 m. 8. Mount Weld sites 600 and 700 m faunas were most similar to Warra sites so forming a continuum in altitudinal zonation between Warra and Mount Weld. 9. PERMANOVA analysis of monthly pitfall catches in 2001 and 2002 showed differences between months and altitudes on both transects and that the differences between months were more distinct at the lower altitude Warra sites than on the higher altitude Mount Weld sites. This difference was particularly marked for the month of February, which was the only month surveyed in both years. 10.Much of the change in faunal assemblages along the Warra and Mount Weld altitudinal transect seemed to be the result of changes in vegetation cover. The most abrupt faunal transitions took place across the tree line between 1000 and 1100 m and a smaller change from lowland forest to subalpine woodland on the Mount Weld transect. 11.Much material in the pitfalls was in very poor condition because of the long trapping time with unsuitable preservative so could not be identified to species but rough estimates were made of numbers of individuals in each family or genus.
Health effects associated with inhalation of airborne arsenic arising from mining operations
- Martin, Rachael, Dowling, Kim, Pearce, Dora, Sillitoe, Jim, Florentine, Singarayer
- Authors: Martin, Rachael , Dowling, Kim , Pearce, Dora , Sillitoe, Jim , Florentine, Singarayer
- Date: 2014
- Type: Text , Journal article
- Relation: Geosciences (Switzerland) Vol. 4, no. 3 (2014), p. 128-175
- Full Text:
- Reviewed:
- Description: Arsenic in dust and aerosol generated by mining, mineral processing and metallurgical extraction industries, is a serious threat to human populations throughout the world. Major sources of contamination include smelting operations, coal combustion, hard rock mining, as well as their associated waste products, including fly ash, mine wastes and tailings. The number of uncontained arsenic-rich mine waste sites throughout the world is of growing concern, as is the number of people at risk of exposure. Inhalation exposures to arsenic-bearing dusts and aerosol, in both occupational and environmental settings, have been definitively linked to increased systemic uptake, as well as carcinogenic and non-carcinogenic health outcomes. It is therefore becoming increasingly important to identify human populations and sensitive sub-populations at risk of exposure, and to better understand the modes of action for pulmonary arsenic toxicity and carcinogenesis. In this paper we explore the contribution of smelting, coal combustion, hard rock mining and their associated waste products to atmospheric arsenic. We also report on the current understanding of the health effects of inhaled arsenic, citing results from various toxicological, biomedical and epidemiological studies. This review is particularly aimed at those researchers engaged in the distinct, but complementary areas of arsenic research within the multidisciplinary field of medical geology. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
- Authors: Martin, Rachael , Dowling, Kim , Pearce, Dora , Sillitoe, Jim , Florentine, Singarayer
- Date: 2014
- Type: Text , Journal article
- Relation: Geosciences (Switzerland) Vol. 4, no. 3 (2014), p. 128-175
- Full Text:
- Reviewed:
- Description: Arsenic in dust and aerosol generated by mining, mineral processing and metallurgical extraction industries, is a serious threat to human populations throughout the world. Major sources of contamination include smelting operations, coal combustion, hard rock mining, as well as their associated waste products, including fly ash, mine wastes and tailings. The number of uncontained arsenic-rich mine waste sites throughout the world is of growing concern, as is the number of people at risk of exposure. Inhalation exposures to arsenic-bearing dusts and aerosol, in both occupational and environmental settings, have been definitively linked to increased systemic uptake, as well as carcinogenic and non-carcinogenic health outcomes. It is therefore becoming increasingly important to identify human populations and sensitive sub-populations at risk of exposure, and to better understand the modes of action for pulmonary arsenic toxicity and carcinogenesis. In this paper we explore the contribution of smelting, coal combustion, hard rock mining and their associated waste products to atmospheric arsenic. We also report on the current understanding of the health effects of inhaled arsenic, citing results from various toxicological, biomedical and epidemiological studies. This review is particularly aimed at those researchers engaged in the distinct, but complementary areas of arsenic research within the multidisciplinary field of medical geology. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
Effects of Tetranychus lintearius (Acari : Tetranychidae) on the structure and water potential in the foliage of the invasive Ulex europaeus (Fabaceae) in Australia
- Marriott, Jeremy, Florentine, Singarayer, Raman, Anantanarayanan
- Authors: Marriott, Jeremy , Florentine, Singarayer , Raman, Anantanarayanan
- Date: 2013
- Type: Text , Journal article
- Relation: International Journal of Acarology Vol. 39, no. 4 (2013), p. 275-284
- Full Text:
- Reviewed:
- Description: Ulex europaeus, a native of Western Europe and the Mediterranean coast, is a serious agricultural and environmental weed in many parts of the earth, including Australia. Tetranychus lintearius attacks U. europaeus in its natural range and is one of the four biological control agents introduced into Australia to regulate populations of U. europaeus. Tetranychus lintearius is specific to different species of Ulex, which enhances its status as a key biological control agent. Little is known on the physiological effects and structural changes induced by T. lintearius on U. europaeus. This article describes anatomical changes and evaluates the physiological effects in U. europaeus consequent to feeding by T. lintearius for more than 100 d. This study demonstrates that feeding by T. lintearius reduces the quantity of photosynthetic tissue in U. europaeus, as a result of feeding on mesophyll parenchyma by inserting its stylets through the stomatal aperture. Unfed parenchyma cells display signs of stress, either exhibiting deformed cell organelles aligned along the walls of vacant cells or with cells with no well-defined cell organelles. Subsequent to T. lintearius feeding, leaves externally manifest bleaching. After feeding by a population of T. lintearius, leaf water potential is decreased by 30% and tender shoots lose their turgor, indicating water-related stress. Tetranychus lintearius has the potential to decelerate vigour and retard the competitiveness of U. europaeus by inflicting stress. Our findings reinforce the use of T. lintearius in the biological management of populations of U. europaeus in temperate Australia.
- Authors: Marriott, Jeremy , Florentine, Singarayer , Raman, Anantanarayanan
- Date: 2013
- Type: Text , Journal article
- Relation: International Journal of Acarology Vol. 39, no. 4 (2013), p. 275-284
- Full Text:
- Reviewed:
- Description: Ulex europaeus, a native of Western Europe and the Mediterranean coast, is a serious agricultural and environmental weed in many parts of the earth, including Australia. Tetranychus lintearius attacks U. europaeus in its natural range and is one of the four biological control agents introduced into Australia to regulate populations of U. europaeus. Tetranychus lintearius is specific to different species of Ulex, which enhances its status as a key biological control agent. Little is known on the physiological effects and structural changes induced by T. lintearius on U. europaeus. This article describes anatomical changes and evaluates the physiological effects in U. europaeus consequent to feeding by T. lintearius for more than 100 d. This study demonstrates that feeding by T. lintearius reduces the quantity of photosynthetic tissue in U. europaeus, as a result of feeding on mesophyll parenchyma by inserting its stylets through the stomatal aperture. Unfed parenchyma cells display signs of stress, either exhibiting deformed cell organelles aligned along the walls of vacant cells or with cells with no well-defined cell organelles. Subsequent to T. lintearius feeding, leaves externally manifest bleaching. After feeding by a population of T. lintearius, leaf water potential is decreased by 30% and tender shoots lose their turgor, indicating water-related stress. Tetranychus lintearius has the potential to decelerate vigour and retard the competitiveness of U. europaeus by inflicting stress. Our findings reinforce the use of T. lintearius in the biological management of populations of U. europaeus in temperate Australia.
Plant recruitment and survival as indicators of ecological success in abandoned pasture land in Nurcoung
- Florentine, Singarayer, Gardner, Jessica, Graz, Patrick, Moloney, Sean
- Authors: Florentine, Singarayer , Gardner, Jessica , Graz, Patrick , Moloney, Sean
- Date: 2013
- Type: Text , Journal article
- Relation: Ecological Processes Vol. 2, no. 1-3 (2013), p.
- Full Text:
- Reviewed:
- Description: One of the major impediments to developing better restoration strategies is the inadequate documentation of past restoration efforts. In 2008, Greening Australia commenced ecological restoration on the Nurcoung property in Victoria to enhance local biodiversity, and in this paper we report on the habitat restoration outcomes in the three Ecological Vegetation Classes (EVC) found on this property.
- Authors: Florentine, Singarayer , Gardner, Jessica , Graz, Patrick , Moloney, Sean
- Date: 2013
- Type: Text , Journal article
- Relation: Ecological Processes Vol. 2, no. 1-3 (2013), p.
- Full Text:
- Reviewed:
- Description: One of the major impediments to developing better restoration strategies is the inadequate documentation of past restoration efforts. In 2008, Greening Australia commenced ecological restoration on the Nurcoung property in Victoria to enhance local biodiversity, and in this paper we report on the habitat restoration outcomes in the three Ecological Vegetation Classes (EVC) found on this property.
Recruitment and functionality traits as biondicators of ecological restoration success in the Lurg Hills district, Victoria, Australia
- Monie, Kristin, Florentine, Singarayer, Palmer, Grant
- Authors: Monie, Kristin , Florentine, Singarayer , Palmer, Grant
- Date: 2013
- Type: Text , Journal article
- Relation: Ecological Processes Vol. 2, no. 27 (2013), p. 1-11
- Full Text:
- Reviewed:
- Description: Introduction The Regent Honeyeater Project commenced ecological restoration in the Lurg district in 1994, with an aim to restore habitats for the critically endangered Regent Honeyeater Anthochaera phrygia and a range of other threatened and declining species. Within this context, our study aimed to explore whether plant reproduction can be an effective measure of ecological restoration success. Methods Evaluation involved comparing attributes at unrestored, restored and remnant sites to establish whether sites displayed evidence of a clear restoration trajectory. Five age classes (unrestored, 4–6 years old, 8–10 years old, 12–14 years old and remnant areas) and two landforms (upper hills and lower hills) were considered. The diversity of woody plant species—which have easily recognisable reproductive material and which all recruit seedlings—provides easily measured parameters that have the potential to allow the determination of early establishment success and long-term ecological development of restored ecosystems. Results Restoration plantings developed in a hybrid state towards a benchmark in the lower hills; seedling species composition differed significantly among age classes, increasing in similarity with time since restoration, with some divergence from the target pathway. Composition of functional groups with reproductive outputs was also significantly different among age classes; however, a restoration trajectory was only evident in the upper hills where sites converged towards the target goal. Conclusions Divergence or deviation from the restoration trajectory was not deemed to be a restoration failure, as the variety of functional groups with fruits and diversity of seedlings recruiting indicated a potential increase in resilience in the future due to greater variability across the landscape. Plant recruitment was effective in detecting development trends towards a restoration target in this study and therefore may be a useful measure that contributes to determining ecological restoration success
- Authors: Monie, Kristin , Florentine, Singarayer , Palmer, Grant
- Date: 2013
- Type: Text , Journal article
- Relation: Ecological Processes Vol. 2, no. 27 (2013), p. 1-11
- Full Text:
- Reviewed:
- Description: Introduction The Regent Honeyeater Project commenced ecological restoration in the Lurg district in 1994, with an aim to restore habitats for the critically endangered Regent Honeyeater Anthochaera phrygia and a range of other threatened and declining species. Within this context, our study aimed to explore whether plant reproduction can be an effective measure of ecological restoration success. Methods Evaluation involved comparing attributes at unrestored, restored and remnant sites to establish whether sites displayed evidence of a clear restoration trajectory. Five age classes (unrestored, 4–6 years old, 8–10 years old, 12–14 years old and remnant areas) and two landforms (upper hills and lower hills) were considered. The diversity of woody plant species—which have easily recognisable reproductive material and which all recruit seedlings—provides easily measured parameters that have the potential to allow the determination of early establishment success and long-term ecological development of restored ecosystems. Results Restoration plantings developed in a hybrid state towards a benchmark in the lower hills; seedling species composition differed significantly among age classes, increasing in similarity with time since restoration, with some divergence from the target pathway. Composition of functional groups with reproductive outputs was also significantly different among age classes; however, a restoration trajectory was only evident in the upper hills where sites converged towards the target goal. Conclusions Divergence or deviation from the restoration trajectory was not deemed to be a restoration failure, as the variety of functional groups with fruits and diversity of seedlings recruiting indicated a potential increase in resilience in the future due to greater variability across the landscape. Plant recruitment was effective in detecting development trends towards a restoration target in this study and therefore may be a useful measure that contributes to determining ecological restoration success
Nitrate import-export dynamics in groundwater interacting with surface-water in a wet-tropical environment
- Rasiah, Velu, Armour, John, Cogle, A.L., Florentine, Singarayer
- Authors: Rasiah, Velu , Armour, John , Cogle, A.L. , Florentine, Singarayer
- Date: 2010
- Type: Text , Journal article
- Relation: Australian Journal of Soil Research Vol. 48, no. 4 (2010), p. 361-370
- Full Text:
- Reviewed:
- Description: Solute import-export dynamics in groundwater (GW) systems interacting with surface-water are complex, particularly under farming systems receiving high fertiliser/pesticide inputs in high rainfall regions. We investigated whether any linkage existed between nitrate-N in: (i) leachate (LC) collected at similar to 1m depth under banana (Musa) and that in GW, and (ii) GW and drain-water (DW). We also assessed the hazard/risk of the concentrations against the trigger values proposed for the sustainable health of different aquatic ecosystems. The LC, GW, and DW samples were collected at short intervals during 3 consecutive rainy seasons (January-July) from a similar to 300-ha banana farm in the wet tropical Tully River Catchment in north-east Queensland, Australia. Water samples were analysed for nitrate-N, dissolved organic carbon, and electrical conductivity. The coefficients of variation, ranging from 13 to 132%, obtained for solute concentrations in LC, GW, and DW indicated large within-and between-season temporal variations. The mean nitrate-N concentrations in LC, GW, and DW were 5320, 4135, and 1976 mu g/L, respectively, and were orders of magnitude higher than the trigger values proposed for the sustainable health of most of the neighbouring aquatic ecosystems. Significant positive associations, with correlation coefficients ranging from 0.56 to 0.96, existed between rainfall received and LC volume collected, and between LC volume and solute concentration, including nitrate-N, in the LC. Similar associations existed between the solutes in (i) LC and GW and (ii) GW and DW. From these associations we conclude the unused/under-utilised nitrate that leached below the root-zone was imported into the GW by the percolating rainwater and was exported into the drain via GW base-flow discharge.
- Description: 2003008225
- Authors: Rasiah, Velu , Armour, John , Cogle, A.L. , Florentine, Singarayer
- Date: 2010
- Type: Text , Journal article
- Relation: Australian Journal of Soil Research Vol. 48, no. 4 (2010), p. 361-370
- Full Text:
- Reviewed:
- Description: Solute import-export dynamics in groundwater (GW) systems interacting with surface-water are complex, particularly under farming systems receiving high fertiliser/pesticide inputs in high rainfall regions. We investigated whether any linkage existed between nitrate-N in: (i) leachate (LC) collected at similar to 1m depth under banana (Musa) and that in GW, and (ii) GW and drain-water (DW). We also assessed the hazard/risk of the concentrations against the trigger values proposed for the sustainable health of different aquatic ecosystems. The LC, GW, and DW samples were collected at short intervals during 3 consecutive rainy seasons (January-July) from a similar to 300-ha banana farm in the wet tropical Tully River Catchment in north-east Queensland, Australia. Water samples were analysed for nitrate-N, dissolved organic carbon, and electrical conductivity. The coefficients of variation, ranging from 13 to 132%, obtained for solute concentrations in LC, GW, and DW indicated large within-and between-season temporal variations. The mean nitrate-N concentrations in LC, GW, and DW were 5320, 4135, and 1976 mu g/L, respectively, and were orders of magnitude higher than the trigger values proposed for the sustainable health of most of the neighbouring aquatic ecosystems. Significant positive associations, with correlation coefficients ranging from 0.56 to 0.96, existed between rainfall received and LC volume collected, and between LC volume and solute concentration, including nitrate-N, in the LC. Similar associations existed between the solutes in (i) LC and GW and (ii) GW and DW. From these associations we conclude the unused/under-utilised nitrate that leached below the root-zone was imported into the GW by the percolating rainwater and was exported into the drain via GW base-flow discharge.
- Description: 2003008225
Characterising and improving the deteriorating trends in soil physical quality under banana
- Rasiah, Velu, Armour, John, Moody, P., Pattison, A., Lindsay, S., Florentine, Singarayer
- Authors: Rasiah, Velu , Armour, John , Moody, P. , Pattison, A. , Lindsay, S. , Florentine, Singarayer
- Date: 2009
- Type: Text , Journal article
- Relation: Australian Journal of Soil Research Vol. 47, no. 6 (2009), p. 574-584
- Full Text:
- Reviewed:
- Description: Deterioration in soil physical quality under intensive tillage practices is a norm rather than an exception. The objectives of this study were to (i) evaluate total porosity (TP) as an indicator parameter to assess the impact of banana cropping on compaction and infiltration in soils, and (ii) assess the effectiveness of different interrow grass-covers in minimising the deteriorating trends. Depth-incremented TP under banana rows and interrows from 4 sites, corresponding forest sites, and from 3 interrow grass-cover treatments were computed from bulk density measurements. The TP results show the compacted depth ranged from 0.35 to 0.45m in banana rows and from 0.35 to 1.0m in the interrows. The TP in 0.10m depth increments decreased in the order: forest > rows > interrows, and was positively correlated with soil organic C (OC) and negatively with wheel traffic stress (WTS). The multiple regression analysis showed that 77% of the variability in TP was accounted for by clay + silt, OC, and WTS. We show that a threshold compaction index (DIt) of 0.81-0.83 can be estimated from TP regardless of the soil type. Depending on the soil type and the cultural practices followed, infiltration decreased from 0.75 mm/s in rainforest to 0.23 mm/s under banana in 1 soil type compared with 2.55 mm/s in forest and 0.85 mm/s under banana in another. After 18 months of interrow grass-covers we found the deterioration in TP was minimum under the indigenous grass-cover but not under the 2 improved species. We conclude the interrow grass-covers were effective in minimising WTS associated compaction and reduction in infiltration.
- Authors: Rasiah, Velu , Armour, John , Moody, P. , Pattison, A. , Lindsay, S. , Florentine, Singarayer
- Date: 2009
- Type: Text , Journal article
- Relation: Australian Journal of Soil Research Vol. 47, no. 6 (2009), p. 574-584
- Full Text:
- Reviewed:
- Description: Deterioration in soil physical quality under intensive tillage practices is a norm rather than an exception. The objectives of this study were to (i) evaluate total porosity (TP) as an indicator parameter to assess the impact of banana cropping on compaction and infiltration in soils, and (ii) assess the effectiveness of different interrow grass-covers in minimising the deteriorating trends. Depth-incremented TP under banana rows and interrows from 4 sites, corresponding forest sites, and from 3 interrow grass-cover treatments were computed from bulk density measurements. The TP results show the compacted depth ranged from 0.35 to 0.45m in banana rows and from 0.35 to 1.0m in the interrows. The TP in 0.10m depth increments decreased in the order: forest > rows > interrows, and was positively correlated with soil organic C (OC) and negatively with wheel traffic stress (WTS). The multiple regression analysis showed that 77% of the variability in TP was accounted for by clay + silt, OC, and WTS. We show that a threshold compaction index (DIt) of 0.81-0.83 can be estimated from TP regardless of the soil type. Depending on the soil type and the cultural practices followed, infiltration decreased from 0.75 mm/s in rainforest to 0.23 mm/s under banana in 1 soil type compared with 2.55 mm/s in forest and 0.85 mm/s under banana in another. After 18 months of interrow grass-covers we found the deterioration in TP was minimum under the indigenous grass-cover but not under the 2 improved species. We conclude the interrow grass-covers were effective in minimising WTS associated compaction and reduction in infiltration.
Controlling wind blown Lachnagrostis filiformis (fairy grass) seed heads in western Victoria
- Warnock, Andrew, Florentine, Singarayer, Graz, Patrick, Westbrooke, Martin
- Authors: Warnock, Andrew , Florentine, Singarayer , Graz, Patrick , Westbrooke, Martin
- Date: 2009
- Type: Text , Conference paper
- Relation: Paper presented at Fourth Victorian Weed Conference : Plants behaving badly - in agriculture and the environment, Mercure Hotel, Geelong, Victoria : 7th-8th October 2009
- Full Text:
- Description: 2003007372
- Authors: Warnock, Andrew , Florentine, Singarayer , Graz, Patrick , Westbrooke, Martin
- Date: 2009
- Type: Text , Conference paper
- Relation: Paper presented at Fourth Victorian Weed Conference : Plants behaving badly - in agriculture and the environment, Mercure Hotel, Geelong, Victoria : 7th-8th October 2009
- Full Text:
- Description: 2003007372
- Warnock, Andrew, Florentine, Singarayer, Graz, Patrick, Westbrooke, Martin
- Authors: Warnock, Andrew , Florentine, Singarayer , Graz, Patrick , Westbrooke, Martin
- Date: 2008
- Type: Text , Conference paper
- Relation: Paper presented at 16th Australian Weeds Conference: Weed management 2008 hot topics in the tropics, Cairns, Queensland : May 18th-22nd, 2008 p. 165-167
- Full Text:
- Description: The native fairy grass (Lachnagrostis filiformis (G. Forst.) Trin.) has colonised extensive areas of dry lake beds in western Victoria during the current drought. Large numbers of the plants’ detached mature panicles (seed heads) lodge against housing, fences, railway lines and other obstacles. This can be a fire hazard, degrades township aesthetics and creates a general nuisance to communities of lakeside towns. Current control measures are costly and only provide short-term solutions. A three-year study commencing in 2006 was designed to assess current and innovative control measures and develop a potential long-term management solution to the problem. Treatments applied to the bed of Lake Learmonth during the first year of the study included late-season glyphosate herbicide at two concentrations, late-season slashing, and seed broadcasting of two native species to reduce L. filiformis inflorescence biomass through competition. Slashing reduced L. filiformis inflorescence biomass and herbicide treatments successfully killed L. filiformis plants, while having no effect on germination of seed collected from sprayed plants. Although these treatments successfully limited the impact of L. filiformis on lakeside towns during the first year, the longer term efficiency is doubted. Treatment effects will be monitored over a further two years.
- Description: 2003006269
Age distribution of Slender Cypress-pine (Callitris gracilis) within Pine Plains, Wyperfeld National Park
- Gibson, Matthew, Florentine, Singarayer
- Authors: Gibson, Matthew , Florentine, Singarayer
- Date: 2008
- Type: Text , Report
- Full Text:
- Description: In semi-arid north-west Victoria, Slender Cypress-pine (Callitris gracilis) is an important tree hollow forming species for hollow dependent fauna, particularly the Major Mitchell’s Cockatoo (Lophocroa leadbeateri). Long-term management of the Major Mitchell’s Cockatoo must be based on an understanding of the age distribution of Slender Cypress-pine within important habitat areas and the age at which the trees form suitable nesting hollows. This project involved an investigation of the Slender Cypress-pine population within the Pine Plains section of Wyperfeld National Park, north-west Victoria. The objectives of the project were to determine the relationship between stem diameter and age of Slender Cypress-pine, and investigate the age distribution of the Slender Cypress-pine population within Pine Plains. Determination of the relationship between stem diameter and stem age will enable the determination of the number of years trees require to start forming hollows, and to form large hollows suitable for Major Mitchell’s Cockatoo breeding.
- Authors: Gibson, Matthew , Florentine, Singarayer
- Date: 2008
- Type: Text , Report
- Full Text:
- Description: In semi-arid north-west Victoria, Slender Cypress-pine (Callitris gracilis) is an important tree hollow forming species for hollow dependent fauna, particularly the Major Mitchell’s Cockatoo (Lophocroa leadbeateri). Long-term management of the Major Mitchell’s Cockatoo must be based on an understanding of the age distribution of Slender Cypress-pine within important habitat areas and the age at which the trees form suitable nesting hollows. This project involved an investigation of the Slender Cypress-pine population within the Pine Plains section of Wyperfeld National Park, north-west Victoria. The objectives of the project were to determine the relationship between stem diameter and age of Slender Cypress-pine, and investigate the age distribution of the Slender Cypress-pine population within Pine Plains. Determination of the relationship between stem diameter and stem age will enable the determination of the number of years trees require to start forming hollows, and to form large hollows suitable for Major Mitchell’s Cockatoo breeding.
- Florentine, Singarayer, Westbrooke, Martin, Milberg, Per, Gibson, Matthew
- Authors: Florentine, Singarayer , Westbrooke, Martin , Milberg, Per , Gibson, Matthew
- Date: 2008
- Type: Text , Journal article
- Relation: Australian Forestry Vol. 71, no. 1 (2008), p. 48-53
- Full Text:
- Reviewed:
- Description: During June 1998, a severe windstorm caused significant damage to a sub-alpine stand of Eucalyptus delegatensis (Myrtaceae) at the Snowy River National Park. In 2002, about 4.5 y after the windstorm, a study documented the effects on E. delegatensis and early understorey succession. In February 2003, wildfire burnt across the windthrow site and we examined the seedling recruitment patterns at windthrow–burn and burn-only sites. Our aim was to document the regeneration of the canopy-dominant E. delegatensis and to confirm that Acacia dealbata is a pioneer species that potentially interferes with or prevents regeneration of E. delegatensis. Permanent transects were established within the windthrow–burn and burn-only sites. The data suggest that the heavily disturbed (mounded) soil at the windthrow site had a strong positive influence on regeneration of both species. By providing favourable growing conditions, the disturbed soil appears to have assisted seedling survival and subsequent growth of the E. delegatensis, despite competition from dense, concurrently established A. dealbata.
- Description: C1
Does Geijera parviflora Lindl. (Rutaceae) facilitate understorey species in semi-arid Australia?
- Warnock, Andrew, Westbrooke, Martin, Florentine, Singarayer, Hurst, Cameron
- Authors: Warnock, Andrew , Westbrooke, Martin , Florentine, Singarayer , Hurst, Cameron
- Date: 2007
- Type: Text , Journal article
- Relation: Rangeland Journal Vol. 29, no. 2 (2007), p. 207-216
- Full Text:
- Reviewed:
- Description: Species composition under tree canopies often differs from that of surrounding micro-environments. In arid and semi-arid zones, trees can be beneficial to understorey vegetation. This study examined zones of vegetation composition and soil physiochemical parameters associated with Geijera parviflora Lindl. The importance of shade, rainfall redistribution, seed bank and soil moisture were examined. Species abundance, soil moisture, seed bank composition, rainfall redistribution and soil nutrient concentration were measured under five randomly selected mature G. parviflora trees in south-western New South Wales, Australia. To complement the findings from this study, artificial shade plots were constructed in a canopy-free area and species abundance measured seven months after shade construction. The study demonstrated that G. parviflora was associated with zonation of understorey vegetation. Two zones of understorey vegetation were found in relation to G. parviflora: (i) under the tree canopy with high species diversity, and (ii) beyond the canopy, this community being dominated by Dissocarpus paradoxus throughout the year with Crassula colorata appearing after rainfall. The zone beyond the canopy also had lower soil nutrient concentrations. Soil moisture, nutrient concentration and the seed bank density were significantly higher under the canopy. However, the canopy reduced precipitation reaching the soil surface. The effects of the canopy on understorey species composition and soil moisture were enhanced after winter rainfall. Artificial shade increased species abundance and richness under a 90%-shading treatment. The results indicated that G. parviflora generated spatial heterogeneity over the broader plant community increasing species richness, abundance and diversity under the canopy. This emphasises the importance of arid zone trees in conserving understorey plant diversity. Shading, soil nutrient concentration and increased seed bank density and soil moisture appeared to be key influences on the plant communities under the canopy. © Australian Rangeland Society 2007.
- Description: C1
- Description: 2003004817
- Authors: Warnock, Andrew , Westbrooke, Martin , Florentine, Singarayer , Hurst, Cameron
- Date: 2007
- Type: Text , Journal article
- Relation: Rangeland Journal Vol. 29, no. 2 (2007), p. 207-216
- Full Text:
- Reviewed:
- Description: Species composition under tree canopies often differs from that of surrounding micro-environments. In arid and semi-arid zones, trees can be beneficial to understorey vegetation. This study examined zones of vegetation composition and soil physiochemical parameters associated with Geijera parviflora Lindl. The importance of shade, rainfall redistribution, seed bank and soil moisture were examined. Species abundance, soil moisture, seed bank composition, rainfall redistribution and soil nutrient concentration were measured under five randomly selected mature G. parviflora trees in south-western New South Wales, Australia. To complement the findings from this study, artificial shade plots were constructed in a canopy-free area and species abundance measured seven months after shade construction. The study demonstrated that G. parviflora was associated with zonation of understorey vegetation. Two zones of understorey vegetation were found in relation to G. parviflora: (i) under the tree canopy with high species diversity, and (ii) beyond the canopy, this community being dominated by Dissocarpus paradoxus throughout the year with Crassula colorata appearing after rainfall. The zone beyond the canopy also had lower soil nutrient concentrations. Soil moisture, nutrient concentration and the seed bank density were significantly higher under the canopy. However, the canopy reduced precipitation reaching the soil surface. The effects of the canopy on understorey species composition and soil moisture were enhanced after winter rainfall. Artificial shade increased species abundance and richness under a 90%-shading treatment. The results indicated that G. parviflora generated spatial heterogeneity over the broader plant community increasing species richness, abundance and diversity under the canopy. This emphasises the importance of arid zone trees in conserving understorey plant diversity. Shading, soil nutrient concentration and increased seed bank density and soil moisture appeared to be key influences on the plant communities under the canopy. © Australian Rangeland Society 2007.
- Description: C1
- Description: 2003004817
Metabolite mobilization in the stem galls of Parthenium hysterophorus induced by Epiblema strenuana inferred from the signatures of isotopic carbon and nitrogen and concentrations of total non-structural carbohydrates
- Florentine, Singarayer, Raman, Anantanarayanan, Dhileepan, Kunjithapatham, Madhaven, S.
- Authors: Florentine, Singarayer , Raman, Anantanarayanan , Dhileepan, Kunjithapatham , Madhaven, S.
- Date: 2006
- Type: Text , Journal article
- Relation: Entomologia Experimentalis et Applicata Vol. 119, no. (2006), p. 101-107
- Full Text:
- Reviewed:
- Description: Parthenium hysterophorus L. (Asteraceae) is a weed of national significance in Australia. Among the several arthropod agents introduced into Australia to control populations of P. hysterophorus biologically, Epiblema strenuana Walker (Lepidoptera: Tortricidae) is the most widespread and abundant agent. By intercepting the normal transport mechanisms of P. hysterophorus, the larvae of E. strenuana drain nutrients, other metabolic products, and energy, and place the host plant under intense metabolic stress. In this study, determinations of total non-structural carbohydrates (TNC) levels and carbon and nitrogen isotope ratios of fixed products in different parts of the plant tissue, including the gall, have been made to establish the function of gall as a sink for the nutrients Values of
- Description: C1
- Description: 2003001571
- Authors: Florentine, Singarayer , Raman, Anantanarayanan , Dhileepan, Kunjithapatham , Madhaven, S.
- Date: 2006
- Type: Text , Journal article
- Relation: Entomologia Experimentalis et Applicata Vol. 119, no. (2006), p. 101-107
- Full Text:
- Reviewed:
- Description: Parthenium hysterophorus L. (Asteraceae) is a weed of national significance in Australia. Among the several arthropod agents introduced into Australia to control populations of P. hysterophorus biologically, Epiblema strenuana Walker (Lepidoptera: Tortricidae) is the most widespread and abundant agent. By intercepting the normal transport mechanisms of P. hysterophorus, the larvae of E. strenuana drain nutrients, other metabolic products, and energy, and place the host plant under intense metabolic stress. In this study, determinations of total non-structural carbohydrates (TNC) levels and carbon and nitrogen isotope ratios of fixed products in different parts of the plant tissue, including the gall, have been made to establish the function of gall as a sink for the nutrients Values of
- Description: C1
- Description: 2003001571
The arid land invasive weed Nicotiana glauca R. Graham (Solanaceae) : Population and soil seed bank dynamics, seed germination patterns and seedling response to flood and drought
- Florentine, Singarayer, Westbrooke, Martin, Gosney, Kathleen, Ambrose, Graeme, O’Keefe, M.
- Authors: Florentine, Singarayer , Westbrooke, Martin , Gosney, Kathleen , Ambrose, Graeme , O’Keefe, M.
- Date: 2006
- Type: Text , Journal article
- Relation: Journal of Arid Environments Vol. 66, no. (2006), p. 218-230
- Full Text:
- Reviewed:
- Description: Disturbances in plant communities provide opportunities for weed germination, propagation, spread, and invasion. When the population density of a weed increases, fast-tracked and appropriate control management strategies are required. The objectives of this study were to: (i) examine the population and soil seed bank dynamics of Nicotiana glauca; (ii) compare the germination patterns of invasive N. glauca seeds collected from two states in Australia, and (iii) investigate the impact of a flood in September 1997 and subsequent drought on N. glauca seedlings. The density of N. glauca followed a steep positive increment during the sampling time (September 1999 to October 2004). The increment pattern was similar in flooded fenced and unfenced plots. Plant density increased over much of the observation period, but had declined to 80 and 432 stems ha−1, respectively, by October 2004. Stem density recorded in October 2004 along two transects radiating from the central point of the newly created lake demonstrated that a significant number of stems appeared to be dead. A soil seed bank study revealed that seed density varied significantly (p=0.0001) between flooded fenced (598.75±71) and flooded unfenced (327.5±66) plots. In contrast, no N. glauca seedlings were recruited from the soil collected from the control plots. Germination trials were undertaken on N. glauca seed collected from New South Wales. There was no significance difference detected between treatments light and temperature. Similarly, no interaction was found between light and temperature. A comparative study on seed germination patterns of N. glauca seeds collected from Ivanhoe, New South Wales, and the Flinders Ranges, South Australia, showed that temperature had a significant effect on N. glauca seed germination. The effect varied significantly with main variables (state, length and time) and also with different interactions, except state×light (p=0.3840). N. glauca seedlings exposed to flood were found to withstand partial flooding for at least 58 days. Under waterlogged conditions, the seedlings showed stem hypertrophy and produced adventitious roots. Only one seedling was found dead in the drought treatment. In conclusion, it is clear that N. glauca invaded the area after a rare flood event and began to function as a casual weed. Established seedlings in the field can withstand extreme ecological events such as flood and drought. Understanding the plants’ ecological characteristics through a study such as this at an early rather than late stage in the invasion will help us to take appropriate control measures for this species.
- Description: C1
- Description: 2003001616
- Authors: Florentine, Singarayer , Westbrooke, Martin , Gosney, Kathleen , Ambrose, Graeme , O’Keefe, M.
- Date: 2006
- Type: Text , Journal article
- Relation: Journal of Arid Environments Vol. 66, no. (2006), p. 218-230
- Full Text:
- Reviewed:
- Description: Disturbances in plant communities provide opportunities for weed germination, propagation, spread, and invasion. When the population density of a weed increases, fast-tracked and appropriate control management strategies are required. The objectives of this study were to: (i) examine the population and soil seed bank dynamics of Nicotiana glauca; (ii) compare the germination patterns of invasive N. glauca seeds collected from two states in Australia, and (iii) investigate the impact of a flood in September 1997 and subsequent drought on N. glauca seedlings. The density of N. glauca followed a steep positive increment during the sampling time (September 1999 to October 2004). The increment pattern was similar in flooded fenced and unfenced plots. Plant density increased over much of the observation period, but had declined to 80 and 432 stems ha−1, respectively, by October 2004. Stem density recorded in October 2004 along two transects radiating from the central point of the newly created lake demonstrated that a significant number of stems appeared to be dead. A soil seed bank study revealed that seed density varied significantly (p=0.0001) between flooded fenced (598.75±71) and flooded unfenced (327.5±66) plots. In contrast, no N. glauca seedlings were recruited from the soil collected from the control plots. Germination trials were undertaken on N. glauca seed collected from New South Wales. There was no significance difference detected between treatments light and temperature. Similarly, no interaction was found between light and temperature. A comparative study on seed germination patterns of N. glauca seeds collected from Ivanhoe, New South Wales, and the Flinders Ranges, South Australia, showed that temperature had a significant effect on N. glauca seed germination. The effect varied significantly with main variables (state, length and time) and also with different interactions, except state×light (p=0.3840). N. glauca seedlings exposed to flood were found to withstand partial flooding for at least 58 days. Under waterlogged conditions, the seedlings showed stem hypertrophy and produced adventitious roots. Only one seedling was found dead in the drought treatment. In conclusion, it is clear that N. glauca invaded the area after a rare flood event and began to function as a casual weed. Established seedlings in the field can withstand extreme ecological events such as flood and drought. Understanding the plants’ ecological characteristics through a study such as this at an early rather than late stage in the invasion will help us to take appropriate control measures for this species.
- Description: C1
- Description: 2003001616
Arid land vegetation dynamics after a rare flooding event : influence of fire and grazing
- Westbrooke, Martin, Florentine, Singarayer, Milberg, Per
- Authors: Westbrooke, Martin , Florentine, Singarayer , Milberg, Per
- Date: 2005
- Type: Text , Journal article
- Relation: Journal of Arid Environments Vol. 61, no. 2 (Apr 2005), p. 249-260
- Full Text:
- Reviewed:
- Description: Arid vegetation is subjected to more or less frequent fire, drought, and sporadic flooding events and grazing. Whilst fire, drought and grazing have been the subject of considerable research, little is known of the impact of flooding in arid environments. In this study we examined opportunistically the effects of a flooding event, and its interaction with fire and grazing on moulding arid vegetation in New South Wales, Australia. We assessed vegetation approximately 2 and 5 years after recession of the water in fenced and unfenced plots subjected to different combinations of flooding and fire. Number of species per area dropped from 11.8 to 5.7 per 625 m(2). Vegetation in plots left open to grazing by vertebrates differed from fenced plots, but the amount of variation explained was small compared with flooding and the change over time. The taxa mostly associated with flooding were Eragrostis spp., Pseudognaphalium luteoalbum and the exotic Nicotiana glauca. Major flooding events not only trigger native species' germination and recruitment but may also create an avenue for exotic species to invade. (C) 2004 Elsevier Ltd. All rights reserved.
- Description: C1
- Description: 2003001050
- Authors: Westbrooke, Martin , Florentine, Singarayer , Milberg, Per
- Date: 2005
- Type: Text , Journal article
- Relation: Journal of Arid Environments Vol. 61, no. 2 (Apr 2005), p. 249-260
- Full Text:
- Reviewed:
- Description: Arid vegetation is subjected to more or less frequent fire, drought, and sporadic flooding events and grazing. Whilst fire, drought and grazing have been the subject of considerable research, little is known of the impact of flooding in arid environments. In this study we examined opportunistically the effects of a flooding event, and its interaction with fire and grazing on moulding arid vegetation in New South Wales, Australia. We assessed vegetation approximately 2 and 5 years after recession of the water in fenced and unfenced plots subjected to different combinations of flooding and fire. Number of species per area dropped from 11.8 to 5.7 per 625 m(2). Vegetation in plots left open to grazing by vertebrates differed from fenced plots, but the amount of variation explained was small compared with flooding and the change over time. The taxa mostly associated with flooding were Eragrostis spp., Pseudognaphalium luteoalbum and the exotic Nicotiana glauca. Major flooding events not only trigger native species' germination and recruitment but may also create an avenue for exotic species to invade. (C) 2004 Elsevier Ltd. All rights reserved.
- Description: C1
- Description: 2003001050
Ecology of the endangered Southern Shepherd's Purse Ballantinia antipoda (Brassicaceae) and the associated moss mat community on Mount Alexander, Victoria
- Ambrose, Graeme, Florentine, Singarayer, Seidel, Jessica, Wilson, Michael
- Authors: Ambrose, Graeme , Florentine, Singarayer , Seidel, Jessica , Wilson, Michael
- Date: 2005
- Type: Text , Journal article
- Relation: Victorian Naturalist Vol. 122, no. (2005), p. 179-188
- Full Text:
- Reviewed:
- Description: Despite its rarity, conservation status and location within the regional park, there is only limited information on the ecology of B. antipoda. The significance of the micorhabitat provided by the associated moss mat community is unclear.
- Description: 2003001088
- Authors: Ambrose, Graeme , Florentine, Singarayer , Seidel, Jessica , Wilson, Michael
- Date: 2005
- Type: Text , Journal article
- Relation: Victorian Naturalist Vol. 122, no. (2005), p. 179-188
- Full Text:
- Reviewed:
- Description: Despite its rarity, conservation status and location within the regional park, there is only limited information on the ecology of B. antipoda. The significance of the micorhabitat provided by the associated moss mat community is unclear.
- Description: 2003001088