Observations on the Demography of the Australian Boab Adansonia gibbosa) in the North-west of the Northern Territory, Australia

1997 ◽  
Vol 45 (5) ◽  
pp. 893 ◽  
Author(s):  
D. M. J. S. Bowman
Keyword(s):  
National Park ◽  
Fire History ◽  
Fire Regimes ◽  
Fruit Production ◽  
Northern Territory ◽  
Size Class ◽  
Fire Damage ◽  
Trunk Diameter ◽  
Size Classes ◽  
A Site

A study of the size-class distributions of the Australian boab, Adansonia gibbosa (A.Cunn.) Guymer ex D.Baum, a tree endemic to north-western Australia, was conducted in Gregory National Park and Keep River National Park, in the Northern Territory. It was found that populations of A. gibbosa on alluvial plains had high densities of small, immature stems < 10 cm dbh (diameter at breast height), and that the density of immature stems decreased with increasing distance from a river. By contrast, there was an absence of small size classes in a population growing on a sandstone escarpment. On limestone substrates, high densities of small size-class stems were observed at a site topographically protected from wildfire, but there was an absence of small size classes at a site exposed to wildfires. Differences in gross allocation patterns, as inferred from relationships between tree height, trunk diameter and height of the swollen trunk, were observed between alluvial, sandstone and limestone substrates. These differences suggest growth rates also differ on distinct substrates. There was a highly significant negative association between the presence of fruit and evidence of recent fire damage for stems greater than 10 cm dbh. This pattern may be related to the destruction of reproductive structures by late dry season fire. However, additional factors appear to control fruit production, as 36% of the unburnt stems > 10 cm dbh also lacked fruit. Juvenile plants resprout from swollen tap roots after wildfire, thus frequent fires would be required to have a long-term impact on stands of A. gibbosa heavily stocked with juveniles that possess swollen tap roots. However, it is unknown at what age juveniles develop swollen tap roots and if all juveniles with swollen tap roots resprout following fire damage. It is hypothesised that the local distribution of A. gibbosa is controlled by fire history, and that changes in fire regimes associated with cattle grazing are causing changes in the distribution of this species. More research is required to critically evaluate this conjecture.

scholarly journals Visualizing When, Where, and How Fires Happen in U.S. Parks and Protected Areas

2020 ◽  
Vol 9 (5) ◽  
pp. 333
Author(s):  
Nicole C. Inglis ◽  
Jelena Vukomanovic
Keyword(s):  
Decision Making ◽  
Protected Areas ◽  
National Park ◽  
Fire History ◽  
National Park Service ◽  
Fire Management ◽  
Fire Regime ◽  
Fire Regimes ◽  
The United States ◽  
Park Service

Fire management in protected areas faces mounting obstacles as climate change alters disturbance regimes, resources are diverted to fighting wildfires, and more people live along the boundaries of parks. Evidence-based prescribed fire management and improved communication with stakeholders is vital to reducing fire risk while maintaining public trust. Numerous national fire databases document when and where natural, prescribed, and human-caused fires have occurred on public lands in the United States. However, these databases are incongruous and non-standardized, making it difficult to visualize spatiotemporal patterns of fire and engage stakeholders in decision-making. We created interactive decision analytics (“VISTAFiRe”) that transform fire history data into clear visualizations of the spatial and temporal dimensions of fire and its management. We demonstrate the utility of our approach using Big Cypress National Preserve and Everglades National Park as examples of protected areas experiencing fire regime change between 1980 and 2017. Our open source visualizations may be applied to any data from the National Park Service Wildland Fire Events Geodatabase, with flexibility to communicate shifts in fire regimes over time, such as the type of ignition, duration and magnitude, and changes in seasonal occurrence. Application of the tool to Everglades and Big Cypress revealed that natural wildfires are occurring earlier in the wildfire season, while human-caused and prescribed wildfires are becoming less and more common, respectively. These new avenues of stakeholder communication are allowing the National Park Service to devise research plans to prepare for environmental change, guide resource allocation, and support decision-making in a clear and timely manner.

Fire Regimes on Andesitic Mountain Terrain in Northeastern Yellowstone-National-Park, Wyoming

1994 ◽  
Vol 4 (2) ◽  
pp. 65 ◽  
Author(s):  
SW Barrett
Keyword(s):  
Yellowstone National Park ◽  
National Park ◽  
Fire History ◽  
Forest Type ◽  
Lodgepole Pine ◽  
Fire Suppression ◽  
Short Interval ◽  
Fire Regimes ◽  
High Elevation ◽  
Forest Community

A fire history investigation was conducted for three forest community types in the Absaroka Mountains of Yellowstone National Park, Wyoming. Master fire chronologies were based on fire-initiated age classes and tree fire scars. The area's major forest type, lodgepole pine (Pinus contorta Dougl. var. latifolia) ecosystems, revealed a predominant pattern of stand replacing fires with a 200 year mean interval-nearly half the length estimated in previous studies of lodgepole pine on less productive subalpine plateaus in YNP. High elevation whitebark pine (P. albicaulis Engelm.) forests had primarily stand replacing fires with >350 year mean intervals, but some stands near timberline also occasionally experienced mixed severity- or non-lethal underburns. Before nearly a century of effective fire suppression in Yellowstone's northern range, lower elevation Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco.) communities adjacent to Artemesia tridentata (Nutt.) grasslands experienced primarily non-lethal underburns at 30 year mean intervals. While short interval fire regimes have been altered by longterm fire suppression, fire exclusion apparently had only limited influence on the area's infrequently burned ecosystems prior to widespread stand replacement burning in 1988.

scholarly journals Fire History of the Lamar River Drainage, Yellowstone National Park, Wyoming

1989 ◽  
Vol 13 ◽  
pp. 169-173
Author(s):  
Stephen Barrett ◽  
Stephen Arno
Keyword(s):  
Yellowstone National Park ◽  
National Park ◽  
Fire History ◽  
Fire Regime ◽  
Lodgepole Pine ◽  
Fire Regimes ◽  
Pine Forests ◽  
River Drainage ◽  
Tree Ring Data ◽  
History Of

This study's goal is to document the fire history of the Lamar River drainage, southeast of Soda Butte Creek in the Absaroka Mountains of northeastern Yellowstone National Park (YNP). Elsewhere in YNP investigators have documented very long-interval fire regimes for lodgepole pine forests occurring on rhyolitic derived soils (Romme 1982, Romme and Despain 1989) and short-interval fire regimes for the Douglas-fir/grassland types (Houston 1973). No fire regime information was available for lodgepole pine forests on andesitic derived soils, such as in the Lamar drainage. This study will provide managers with a more complete understanding of YNP natural fire history, and the data will supplement the park's Geographic Information System (GIS) data base. Moreover, most of the study area was severely burned in 1988 and historical tree ring data soon will be lost to attrition of potential sample trees.

Fire history in ponderosa pine landscapes of Grand Canyon National Park: is it reliable enough for management and restoration?

2006 ◽  
Vol 15 (3) ◽  
pp. 433 ◽  
Author(s):  
William L. Baker
Keyword(s):  
Ponderosa Pine ◽  
National Park ◽  
Fire History ◽  
Fire Regime ◽  
Grand Canyon ◽  
Fire Risk ◽  
Fire Regimes ◽  
Grand Canyon National Park ◽  
High Severity ◽  
The Impact

Reconstructing fire regimes of the past can provide a valuable frame of reference for understanding the impact of human land uses on contemporary fire and forest structure, but methods for reconstructing past fire regimes are under re-evaluation. In the present article, a common method of characterizing surface fire regimes, using composite fire intervals from fire scars, is shown to significantly underestimate the length of the fire rotation and population mean fire interval in Grand Canyon landscapes where these parameters are known. Also, the evidence and interpretation that past high-severity fire was uncommon in ponderosa pine landscapes in Grand Canyon National Park are challenged. Together, these two concerns mean that an alternative characterization of the fire regime, which has very different implications, cannot be excluded. Management aimed at lowering fire risk, as a means of restoration, does not presently have a sound scientific basis, if it uses the composite fire interval as a measure of the fire regime or is based on fire history research that lacks adequate analysis of past high-severity fire.

Monitoring indicates greater resilience for birds than for mammals in Kakadu National Park, northern Australia

2012 ◽  
Vol 39 (5) ◽  
pp. 397 ◽  
Author(s):  
J. C. Z. Woinarski ◽  
A. Fisher ◽  
M. Armstrong ◽  
K. Brennan ◽  
A. D. Griffiths ◽  
...  
Keyword(s):  
National Park ◽  
Fire History ◽  
Regional Scale ◽  
Monitoring Program ◽  
Bird Species ◽  
Sampling Period ◽  
Fire Regimes ◽  
Individual Species ◽  
Mammal Species ◽  
Bird Abundance

Context A previous study reported major declines for native mammal species from Kakadu National Park, over the period 2001–09. The extent to which this result may be symptomatic of more pervasive biodiversity decline was unknown. Aims Our primary aim was to describe trends in the abundance of birds in Kakadu over the period 2001–09. We assessed whether any change in bird abundance was related to the arrival of invading cane toads (Rhinella marina), and to fire regimes. Methods Birds were monitored at 136 1-ha plots in Kakadu, during the period 2001–04 and again in 2007–09. This program complemented sampling of the same plots over the same period for native mammals. Key results In contrast to the decline reported for native mammals, the richness and total abundance of birds increased over this period, and far more individual bird species increased than decreased. Fire history in the between-sampling period had little influence on trends for individual species. Interpretation of the overall positive trends for bird species in Kakadu over this period should be tempered by recognition that most of the threatened bird species present in Kakadu were unrecorded in this monitoring program, and the two threatened species for which there were sufficient records to assess trends – partridge pigeon (Geophaps smithii) and white-throated grass-wren (Amytornis woodwardi) – both declined significantly. Conclusions The current decline of the mammal fauna in this region is not reflected in trends for the region’s bird fauna. Some of the observed changes (mostly increases) in the abundance of bird species may be due to the arrival of cane toads, and some may be due to local or regional-scale climatic variation or variation in the amount of flowering. The present study provides no assurance about threatened bird species, given that most were inadequately recorded in the study (perhaps because their decline pre-dated the present study). Implications These contrasting trends between mammals and birds demonstrate the need for biodiversity monitoring programs to be broadly based. The declines of two threatened bird species over this period indicate the need for more management focus for these species.

scholarly journals The recent fire history of the Table Mountain National Park and implications for fire management

Koedoe ◽  
2008 ◽  
Vol 50 (1) ◽  
Author(s):  
Greg G. Forsyth ◽  
Brian W. Van Wilgen
Keyword(s):  
National Park ◽  
Fire History ◽  
Prescribed Burning ◽  
Fire Regime ◽  
Weather Conditions ◽  
Fire Regimes ◽  
Management Interventions ◽  
Table Mountain ◽  
Wide Range ◽  
Large Fires

This paper provides an assessment of fire regimes in the Table Mountain National Park over the past four decades. We compiled a GIS database of all fires between 1970 and 2007 and analysed the fire regime in terms of the frequency, season and size of fires and the relationship between fire occurrence and fire weather. Most fires (90.5% of area burnt) occurred in summer and autumn, the ecologically acceptable season for fires. However, mean fire return intervals declined by 18.1 years, from 31.6 to 13.5 years, between the first and last decades of the record respectively. The area subjected to short (≤ six years) intervals between fires covered > 16% of the park in the last two decades of the record, compared to ~ 4% in the first two decades. A relatively small number of large fires dominated in terms of area burnt. Of the 373 fires recorded, 40 fires > 300 ha burnt 75% of the area, while 216 fires < 25 ha burnt 3.4% of the area. Fires occurred under a wide range of weather conditions, but large fires were restricted to periods of high fire danger. Prescribed burning was a relatively unimportant cause of fires, and most (> 85%) of the area burnt in wildfires. Areas subjected to short fire return intervals should be considered for management interventions. These could include the re-establishment of extirpated fire-sensitive species, the clearing of invasive alien plants and increased precautions for the prevention or rapid suppression of future accidental fires.

Screening of F1 progeny for selection of superior hybrids in mulberry (Morus spp.) - A simple approach PART I: Screening of seedlings in relation to seed size

2017 ◽  
Vol 6 (2) ◽  
pp. 5256
Author(s):  
Daryoush Shafiei ◽  
Prof. Basavaiah*
Keyword(s):  
Seed Size ◽  
Seedling Survival ◽  
Size Class ◽  
Medium Size ◽  
Screening Process ◽  
Size Classes ◽  
Morus Spp ◽  
In The Beginning ◽  
Selection Of ◽  
Size Grading

In mulberry (Morus spp.), the process of selection of promising hybrids from F1 population requires the screening of a large number of progenies and a long period. To develop a simple and faster approach for screening, studies were conducted using F1 seeds of two crosses. The details of screening studies conducted in relation to seed-size and seedling-size are reported separately in two parts. In this part, the F1 seeds were size-graded as small, medium and large seeds; their progenies were raised separately and screened in nursery. There was a considerable degree of variation in size of seeds and medium-size class seeds were in high percentage in both the crosses. The length, width and weight of seeds were also varied between the seed size classes significantly in both the crosses. The seed size classes differ with high significance in shoot length and Root collar diameter and also differ significantly in root length and weight of seedlings. The positive correlation between the seed size and growth of seedlings, seed size and germination, seed size and seedling survival in nursery indicated that size-grading of seeds and rejection of small seeds in the beginning of screening process may help to increase the efficiency of screening by increasing the chances of getting superior hybrids from limited progenies. However, confirmation on the performance of large seedlings from small seed size class may help to draw conclusion. Hence, the studies are continued with size- grading of seedlings in the next part of screening study.

scholarly journals A late-Holocene multiproxy fire record from a tropical savanna, eastern Arnhem Land, Northern Territory, Australia

The Holocene ◽  
2021 ◽  
pp. 095968362098803
Author(s):  
Emma Rehn ◽  
Cassandra Rowe ◽  
Sean Ulm ◽  
Craig Woodward ◽  
Michael Bird
Keyword(s):  
Isotope Composition ◽  
Fire Regimes ◽  
Northern Territory ◽  
Ecosystem Dynamics ◽  
Optical Methods ◽  
Fire Intensity ◽  
Tropical Savanna ◽  
Anthropogenic Fire ◽  
Pyrogenic Carbon ◽  
Arnhem Land

Fire has a long history in Australia and is a key driver of vegetation dynamics in the tropical savanna ecosystems that cover one quarter of the country. Fire reconstructions are required to understand ecosystem dynamics over the long term but these data are lacking for the extensive savannas of northern Australia. This paper presents a multiproxy palaeofire record for Marura sinkhole in eastern Arnhem Land, Northern Territory, Australia. The record is constructed by combining optical methods (counts and morphology of macroscopic and microscopic charcoal particles) and chemical methods (quantification of abundance and stable isotope composition of pyrogenic carbon by hydrogen pyrolysis). This novel combination of measurements enables the generation of a record of relative fire intensity to investigate the interplay between natural and anthropogenic influences. The Marura palaeofire record comprises three main phases: 4600–2800 cal BP, 2800–900 cal BP and 900 cal BP to present. Highest fire incidence occurs at ~4600–4000 cal BP, coinciding with regional records of high effective precipitation, and all fire proxies decline from that time to the present. 2800–900 cal BP is characterised by variable fire intensities and aligns with archaeological evidence of occupation at nearby Blue Mud Bay. All fire proxies decline significantly after 900 cal BP. The combination of charcoal and pyrogenic carbon measures is a promising proxy for relative fire intensity in sedimentary records and a useful tool for investigating potential anthropogenic fire regimes.

New species of Drymopsalta Heath Cicadas (Cicadidae: Cicadettinae: Cicadettini) from Queensland and Northern Territory, Australia, with overview of genus

Zootaxa ◽  
2013 ◽  
Vol 3620 (1) ◽  
pp. 1-42
Author(s):  
A. EWART ◽  
L. W. POPPLE
Keyword(s):  
New Species ◽  
High Frequency ◽  
Similar Pattern ◽  
National Park ◽  
Northern Territory ◽  
Allopatric Species ◽  
Temporal Structures ◽  
Cape York ◽  
Three New Species ◽  
Tree Foliage

Three new species are described in the genus Drymopsalta Ewart, previously known only from D. crepitum Ewart and D. daemeli Distant. The three new species occur in Southern Queensland and Northern Territory. D. wallumi sp. nov. occurs along coastal S.E. Queensland, whereas D. hobsoni sp. nov. is restricted to the Bringalily State Forest, near Inglewood, southern inland Queensland. D. acrotela sp. nov. is found in the Litchfield National Park and other locations near Jabaluka, Cahills Crossing, E. Alligator River and Nourlangie, all across the northern Northern Territory. D. crepitum occurs on the Cape York Peninsular extending into the southern Gulf, while D. daemeli occurs in two localised regions in central coastal N.S.W. Each of the species inhabits heath vegetation, often spilling-over into adjacent tree foliage. The species of Drymopsalta are small and inconspicuous cicadas (<15 mm body length) with relatively high frequency songs (~15 to 22 kHz). The temporal structures of the normal calling songs follow a similar pattern in each species, consisting of the emission of short chirps (comprising 2–16 ticks). Between the chirps are emitted one (D. wallumi, D. hobsoni, D. acrotela), two (D. daemeli) or 1–9 (D. crepitum) intervening single ticks. The species can be distinguished by the timing and the number of these single ticks relative to the adjacent chirps with the notable exception of D. hobsoni and D. acrotela. The calling songs of these two allopatric species are indistinguishable, an unusual feature in Australian cicadas. Two additional song variants are described, a more unstructured chirping song without intervening single ticks observed in each of the species except D. crepitum, and periodic extended buzzing echemes emitted within the calling songs (excepting the D. wallumi song).

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