Quantifying the influence of fuel age and weather on the annual extent of unplanned fires in the Sydney region of Australia

2011 ◽  
Vol 20 (1) ◽  
pp. 142 ◽  
Author(s):  
Owen F. Price ◽  
Ross A. Bradstock
Keyword(s):  
Negative Relationship ◽  
Fold Increase ◽  
Influential Factor ◽  
Fire Season ◽  
Annual Rainfall ◽  
Fire Area ◽  
The Mean ◽  
Mixed Modelling ◽  
The Relationship ◽  
Fire Extent

Planned fire is used globally to minimise the risk of unplanned fire, but it is important to measure the return for effort in terms of the reduction of risk per unit area of planned fire. Here, we use 30 years of fire mapping from four subregions of the Sydney region to compare the annual extent of unplanned fire with previous planned and unplanned fire. Using linear mixed modelling, we were able to discriminate the relative influence of previous fire, seasonal rainfall and weather during the peak fire season. The mean annual area burnt over the period was 4.11%, comprising 0.53% planned and 3.58% unplanned. We found that weather during the fire season was the most influential factor. Annual rainfall had a modest negative relationship with unplanned fire area. Past fire had some influence, but the relationship implied that approximately three units of planned fire are required to reduce the unplanned fire area by one unit. Managers would need to burn 5.4% per year to halve unplanned fire extent, a ten-fold increase on recent levels. This would increase the total area burnt, and have other effects that need to be considered (from smoke and greenhouse gas emissions, and changes to biodiversity).

How landscape and climate affect the spatial variability of the Italian rainfall extremes? Some initial clues based on I2-RED

2021 ◽  
Author(s):  
Paola Mazzoglio ◽  
Ilaria Butera ◽  
Pierluigi Claps
Keyword(s):  
Spatial Variability ◽  
Linear Regression Analysis ◽  
Alpine Region ◽  
Annual Rainfall ◽  
Mean Values ◽  
Rainfall Extremes ◽  
Geomorphological Parameters ◽  
The Mean ◽  
The Relationship ◽  
Italian Territory

<p>The intensity and the spatial distribution of precipitation depths are known to be highly dependent on relief and geomorphological parameters. Complex environments like mountainous regions are prone to intense and frequent precipitation events, especially if located near the coastline. Although the link between the mean annual rainfall and geomorphological parameters has received substantial attention, few literature studies investigate the relationship between the sub-daily maximum annual rainfall depth and geographical or morphological landscape features.<br>In this study, the mean of the rainfall extremes in Italy, recently revised in the so-called I<sup>2</sup>-RED dataset, are investigated in their spatial variability in comparison with some landscape and also some broad climatic characteristics. The database includes all sub-daily rainfall extremes recorded in Italy from 1916 until 2019 and this analysis considers their mean values (from 1 to 24 hours) in stations with at least 10 years of records, involving more than 3700 stations.<br>The geo-morpho-climatic factors considered range from latitude, longitude and minimum distance from the coastline on the geographic side, to elevation, slope, openness and obstruction morphological indices, and also include an often-neglected robust climatological information, as the local mean annual rainfall.<br>Obtained results highlight that the relationship between the annual maximum rainfall depths and the hydro-geomorphological parameters is not univocal over the entire Italian territory and over different time intervals. Considering the whole of Italy, the highest correlation is reached between the mean values of the 24-hours records and the mean annual precipitation (correlation coefficient greater than 0.75). This predominance remains also in sub-areas of the Italian territory (i.e., the Alpine region, the Apennines or the coastal areas) but correlation decreases as the time interval decreases, except for the Alpine region (0.73 for the 1-hour maximum). The other geomorphological parameters seem to act in conjunction, making it difficult to evaluate, with a simple linear regression analysis, their impact. As an example, the absolute value of the correlation coefficient between the elevation and the 1-hour extremes is greater than 0.35 for the Italian and the Alpine regions, while for the 24-hours interval it is greater than 0.35 over the coastal areas.<br>To further investigate the spatial variability of the relationship between rainfall and elevation, a spatial linear regression analysis has been undertaken. Local linear relationships have been fitted in circles centered on any of the 0.5-km size pixels in Italy, with 1 to 30 km radius and at least 5 stations included. Results indicate the need of more comprehensive terrain analysis to better understand the causes of local increasing or decreasing relations, poorly described in the available literature.</p>

scholarly journals The Relationship Between Social Support Perceived by Infertile Couples and Their Mental Status

2021 ◽  
Author(s):  
Binnaz AVŞAR ◽  
Tuba GUNER EMUL
Keyword(s):  
Social Support ◽  
Mental Status ◽  
Perceived Social Support ◽  
Negative Relationship ◽  
Infertility Treatment ◽  
Brief Symptom Inventory ◽  
Symptom Inventory ◽  
The Mean ◽  
Infertile Couples ◽  
The Relationship

Abstract Background: Infertility is a difficult process that affects couples psychologically. Providing adequate social support is important in terms of reducing the psychological problems experienced by infertile couples by facilitating compliance with the treatment. Aim/ Objective: This study evaluated the relationship between the mental status of couples receiving infertility treatment and their perceived social support. Methods: The study was descriptive study consisted of 148 infertile couples who received infertility treatment at the InVitro Fertilisation Center between January and April 2018 in a university hospital in Antalya. 148 infertile couples who received infertility treatment at the data of the research were gathered through a questionnaire for determining socio-demographic and infertility related characteristics of the couples receiving infertility treatment, Multidimensional Scale of Perceived Social Support, Brief Symptom Inventory. Results: In the study, the average age of infertile women was 31.4±5.6 and that of men was 34.5±5.2. The mean Multidimensional Scale of Perceived Social Support score of the women was determined to be 62.6±14.2, whereas that of the men 59.2± 14.2. The mean score received by the women from depression subscale of Brief Symptom Inventory was determined to be 10.2±8.9, and the mean score received by the men 6.7±6.6. A strong negative relationship between the total Multidimensional Scale of Perceived Social Supportscore and the Brief Symptom Inventory subscale mean scores (p<0.01). Conclusions: As a result of the research, as the social support levels perceived by couples receiving infertility treatment increased, their symptoms of anxiety, depression, negative self-perception, somatization, and hostility was determined to decrease.

scholarly journals Patient-Reported Allergies, a Marker of Preoperative Pain and Disability in Elective Spine Surgery

2019 ◽  
Vol 10 (5) ◽  
pp. 592-597
Author(s):  
Keith W. Lyons ◽  
Tracy M. Borsinger ◽  
Adriana P. Lucas ◽  
Kevin J. McGuire ◽  
Adam M. Pearson ◽  
...  
Keyword(s):  
Mental Health ◽  
Physical Health ◽  
Neck Disability Index ◽  
Negative Relationship ◽  
Preoperative Pain ◽  
Significant Negative Relationship ◽  
Patient Reported ◽  
The Mean ◽  
And Function ◽  
The Relationship

Study Design: Retrospective review. Objective: Previous literature demonstrates mixed results regarding the relationship between patient-reported allergies and pain, function, and satisfaction scores. The objective of this study was to investigate the correlation between patient-reported allergies and preoperative Oswestry Disability Index (ODI), Neck Disability Index (NDI), and Patient-Reported Outcomes Measurement System (PROMIS) scores. Methods: All patients undergoing elective cervical, lumbar procedures between May 2017 and October 2018 were included. Baseline demographic information was recorded, as well as all reported allergies or adverse reactions. Preoperative PROMIS, ODI, and NDI scores were recorded. Hierarchical multiple linear regressions were used to assess the relationship between total number of allergies and the preoperative pain and function scores. Results: A total of 570 patients were included (476 lumbar, 94 cervical). The mean number of allergies reported was 1.89 ± 2.32. The mean preoperative ODI and NDI scores were 46.39 ± 17.67 and 43.47 ± 16.51, respectively. The mean preoperative PROMIS Physical Health and PROMIS Mental Health scores were 37.21 ± 6.54 and 43.89 ± 9.26, respectively. Hierarchical multiple linear regression showed that total number of reported allergies shared a statistically significant negative relationship with all of the following scores: ODI ( B = 0.83, P = .02), NDI ( B = 1.45, P = .02), PROMIS Physical Health ( B = −0.29, P = .013), and PROMIS Mental Health ( B = −0.38, P = .024). Conclusions: Patient-reported allergies share a statistically significant negative relationship with preoperative pain and function scores; as patients have increasing total number of allergies, the ODI/NDI scores become worse (increase) and the PROMIS scores become worse (decrease).

scholarly journals Evidence for behavioural thermoregulation by the world's largest fish

2013 ◽  
Vol 10 (78) ◽  
pp. 20120477 ◽  
Author(s):  
Michele Thums ◽  
Mark Meekan ◽  
John Stevens ◽  
Steven Wilson ◽  
Jeff Polovina
Keyword(s):  
Surface Waters ◽  
Negative Relationship ◽  
Metabolic Cost ◽  
Vertical Movements ◽  
Rhincodon Typus ◽  
Whale Sharks ◽  
The Mean ◽  
Using Data ◽  
The Relationship ◽  
Body Heat

Many fishes make frequent ascents to surface waters and often show prolonged surface swimming following descents to deep water. This affinity for the surface is thought to be related to the recovery of body heat lost at depth. We tested this hypothesis using data from time–depth recorders deployed on four whale sharks ( Rhincodon typus ). We summarized vertical movements into bouts of dives and classified these into three main types, using cluster analysis. In addition to day and night ‘bounce’ dives where sharks rapidly descended and ascended, we found a third type: single deep (mean: 340 m), long (mean: 169 min) dives, occurring in daytime with extremely long post-dive surface durations (mean: 146 min). Only sharks that were not constrained by shallow bathymetry performed these dives. We found a negative relationship between the mean surface duration of dives in the bout and the mean minimum temperature of dives in the bout that is consistent with the hypothesis that thermoregulation was a major factor driving use of the surface. The relationship broke down when sharks were diving in mean minimum temperatures around 25°C, suggesting that warmer waters did not incur a large metabolic cost for diving and that other factors may also influence surface use.

scholarly journals Kültür Koşullarında Astacus leptodactylus (Eschscholtz, 1823)'un Yumurta Verimliliğinin Belirlenmesi

2019 ◽  
Vol 7 (4) ◽  
pp. 646
Author(s):  
Gülşen Uzun Gören ◽  
Sedat Karayücel ◽  
Birol Baki
Keyword(s):  
Negative Relationship ◽  
Live Weight ◽  
Strong Relationship ◽  
Culture Conditions ◽  
Total Weight ◽  
Astacus Leptodactylus ◽  
Total Length ◽  
The Mean ◽  
Egg Diameter ◽  
The Relationship

In this study, it was aimed to determine there and fecundity by adapting crayfish (Astacus leptodactylus) obtained from Bafra Fish Lakes (Ulugöl-Samsun) in culture conditions. Crayfish obtained in November 2016 were stocked in tanks and egg and morphometric characteristics of female crayfish with carrying eggs were determined. Correlation analysis were used for the relationship between the determined parameters. The mean total weight and total length of crayfish were 41.79±3.00g, 10.72±0.22cm, respectively whereas the mean number and diameter of eggs were 156.40±33.24 and 2.50±0.12mm. There were positive strong relationship between total length and total weight of crayfish negative relationship was found between egg diameter and total number of eggs, egg diameter and total weight of eggs and egg diameter and number of eggs for per unit of live weight.

Relationship between intracellular Po2 recovery kinetics and fatigability in isolated single frog myocytes

2005 ◽  
Vol 98 (6) ◽  
pp. 2316-2319 ◽  
Author(s):  
Casey A. Kindig ◽  
Brandon Walsh ◽  
Richard A. Howlett ◽  
Creed M. Stary ◽  
Michael C. Hogan
Keyword(s):  
Negative Relationship ◽  
Oxidative Capacity ◽  
Metabolic Demand ◽  
Constant Frequency ◽  
Phosphorescence Quenching ◽  
Skeletal Myocytes ◽  
Mean Response Time ◽  
Lumbrical Muscle ◽  
The Mean ◽  
The Relationship

In single frog skeletal myocytes, a linear relationship exists between “fatigability” and oxidative capacity. The purpose of this investigation was to study the relationship between the intracellular Po2 (PiO2) offset kinetics and fatigability in single Xenopus laevis myocytes to test the hypothesis that PiO2 offset kinetics would be related linearly with myocyte fatigability and, by inference, oxidative capacity. Individual myocytes ( n = 30) isolated from lumbrical muscle were subjected to a 2-min bout of isometric peak tetanic contractions at either 0.25- or 0.33-Hz frequency while PiO2 was measured continuously via phosphorescence quenching techniques. The mean response time (MRT; time to 63% of the overall response) for PiO2 recovery from contracting values to resting baseline was calculated. After the initial square-wave constant-frequency contraction trial, each cell performed an incremental contraction protocol [i.e., frequency increase every 2 min from 0.167, 0.25, 0.33, 0.5, 1.0, and 2.0 Hz until peak tension fell below 50% of initial values (TTF)]. TTF values ranged from 3.39 to 10.04 min for the myocytes. The PiO2 recovery MRT ranged from 26 to 146 s. A significant ( P < 0.05), negative relationship (MRT = −12.68TTF + 168.3, r2 = 0.605) between TTF and PiO2 recovery MRT existed. These data demonstrate a significant correlation between fatigability and oxidative phosphorylation recovery kinetics consistent with the notion that oxidative capacity determines, in part, the speed with which skeletal muscle can recover energetically to alterations in metabolic demand.

Relationship between 137Cs in some undisturbed New Zealand soils and rainfall

Soil Research ◽  
1993 ◽  
Vol 31 (5) ◽  
pp. 655 ◽  
Author(s):  
LR Basher ◽  
KM Matthews
Keyword(s):  
New Zealand ◽  
Standard Error ◽  
Soil Samples ◽  
Annual Rainfall ◽  
Strong Correlations ◽  
Atmospheric Fallout ◽  
Coefficients Of Variation ◽  
Local Measurements ◽  
The Mean ◽  
The Relationship

Soil samples were collected from 10 undisturbed sites in South Canterbury and Manawatu, New Zealand, to examine the relationship between 137Cs in soils and rainfall. The results were used to test a previously derived model relating cumulative deposition of 137Cs from atmospheric fallout to mean annual rainfall. There were strong correlations between mean measured levels of 137Cs in soils from the undisturbed sites and rainfall, and between the mean measured levels in soils and those predicted by the model. The moder can therefore be used to estimate input levels of137Cs for erosion studies and to verify the suitability of local measurements of the input value from sites assumed to be undisturbed. Coefficients of variation in soil-Cs at the undisturbed sites ranged up to 30%, indicating that up to 10 samples may be needed to estimate the input value with a standard error � 10%.

Body size effects on pursuit success and interspecific diet differences in Cnemidophorus lizards

2000 ◽  
Vol 21 (4) ◽  
pp. 477-484 ◽  
Author(s):  
Kelly Passek ◽  
Douglas Eifler
Keyword(s):  
Body Size ◽  
Positive Relationship ◽  
Negative Relationship ◽  
Significant Positive Relationship ◽  
Significant Negative Relationship ◽  
Experimental Feeding ◽  
Feeding Trials ◽  
The Mean ◽  
The Relationship ◽  
Cnemidophorus Uniparens

AbstractWe examined the relationship between body size and pursuit success in the lizard Cnemidophorus uniparens. Using grasshoppers as prey in experimental feeding trials, we found a significant positive relationship between lizard body size and pursuit time. In addition, larger individuals were significantly more likely to be unsuccessful at capturing the grasshoppers. We also examined the relationship between the mean body size of Cnemidophorus populations and diet composition. We found a significant negative relationship between mean body size and the proportion of grasshoppers in the diet and a significant positive relationship between mean body size and the proportion of termites in the diet.

scholarly journals Two thresholds determine climatic control of forest-fire size in Europe

2012 ◽  
Vol 9 (7) ◽  
pp. 9065-9089 ◽  
Author(s):  
L. Loepfe ◽  
A. Rodrigo ◽  
F. Lloret
Keyword(s):  
Fire Suppression ◽  
Weather Conditions ◽  
Meteorological Conditions ◽  
Fuel Load ◽  
Fire Season ◽  
Annual Rainfall ◽  
Climate Change Scenarios ◽  
Fire Size ◽  
Large Fires ◽  
Fire Extent

Abstract. Fire weather indices predict fire extent from meteorological conditions assuming a monotonic function; this approach is frequently used to predict future fire patterns under climate change scenarios using linear extrapolation. However, the relationship between weather and fire extent may potentially depend on the existence of fuel humidity thresholds above which this relationship changes dramatically, challenging this statistical approach. Here we combine the continuous and the threshold approaches to analyze satellite-detected fires in Europe during 2001–2010 in relation to meteorological conditions, showing that fire size response to increasing dryness follows a ramp function, i.e. with two plateaus separated by a phase of monotonic increase. This study confirms that at a continental and a high-resolution temporal scales, large fires are very unlikely to occur under moist conditions, but it also reveals that fire size stops to be controlled by fuel humidity above a given threshold of dryness. Thus, fuel humidity control only applies when fire is not limited by other factors such as fuel load, as large fires are virtually absent in dry regions with less than 500 mm of average annual rainfall, i.e. where fuel amount is insufficient. In regions with sufficient fuel, other factors such as fire suppression or fuel discontinuity can impede large fires even under very dry weather conditions. These findings are relevant under current climatic trends in which the fire season length, in terms of number of days with DC (drought code) values above the observed thresholds (break points), is increasing in many parts of the Mediterranean, while it is decreasing in Eastern Europe and remains unchanged in Central Europe.

scholarly journals Projected increases in western US forest fire despite growing fuel constraints

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
John T. Abatzoglou ◽  
David S. Battisti ◽  
A. Park Williams ◽  
Winslow D. Hansen ◽  
Brian J. Harvey ◽  
...  
Keyword(s):  
Interannual Variability ◽  
Forest Fire ◽  
21St Century ◽  
Fold Increase ◽  
Fire Season ◽  
Burned Area ◽  
Western Us ◽  
Fire Area ◽  
Near Term ◽  
Broad Scale

AbstractEscalating burned area in western US forests punctuated by the 2020 fire season has heightened the need to explore near-term macroscale forest-fire area trajectories. As fires remove fuels for subsequent fires, feedbacks may impose constraints on the otherwise climate-driven trend of increasing forest-fire area. Here, we test how fire-fuel feedbacks moderate near-term (2021–2050) climate-driven increases in forest-fire area across the western US. Assuming constant fuels, climate–fire models project a doubling of  forest-fire area compared to 1991–2020. Fire-fuel feedbacks only modestly attenuate the projected increase in forest-fire area. Even models with strong feedbacks project increasing interannual variability in forest-fire area and more than a two-fold increase in the likelihood of years exceeding the 2020 fire season. Fuel limitations from fire-fuel feedbacks are unlikely to strongly constrain the profound climate-driven broad-scale increases in forest-fire area by the mid-21st century, highlighting the need for proactive adaptation to increased western US forest-fire impacts.

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