Remote sensing of burn severity: experience from western Canada boreal fires

2008 ◽  
Vol 17 (4) ◽  
pp. 476 ◽  
Author(s):  
R. J. Hall ◽  
J. T. Freeburn ◽  
W. J. de Groot ◽  
J. M. Pritchard ◽  
T. J. Lynham ◽  
...  
Keyword(s):  
Burn Severity ◽  
Fuel Type ◽  
New Approach ◽  
Burned Areas ◽  
Field Assessment ◽  
Study Results ◽  
Mapping Process ◽  
Single Dataset ◽  
Normalized Burn Ratio ◽  
The Relationship

The severity of a burn for post-fire ecological effects has been assessed with the composite burn index (CBI) and the differenced Normalized Burn Ratio (dNBR). This study assessed the relationship between these two variables across recently burned areas located in the western Canadian boreal, a region not extensively evaluated in previous studies. Of particular interest was to evaluate the nature of the CBI–dNBR relationship from the perspectives of modelling, the influence of fire behaviour prediction (FBP) fuel type, and how field observations could be incorporated into the burn severity mapping process. A non-linear model form best represented the relationship between these variables for the fires evaluated, and a similar statistical performance was achieved when data from all fires were pooled into a single dataset. Results from this study suggest the potential to develop a single model for application over the western region of the boreal, but further evaluation is necessary. This evaluation could include stratification by FBP fuel type due to study results that document its apparent influence on dNBR values. A new approach for burn severity mapping was introduced by defining severity thresholds through field assessment of CBI, and from which development of new models could be incorporated directly into the mapping process.

scholarly journals Quantificação da Severidade das Queimadas e da Perda de Sequestro Florestal de Carbono em Unidades de Conservação do Distrito Federal (Measurement of Severity of Fires and Loss of Carbon Forest sink in the Conservation Units at Distrito Federal)

2016 ◽  
Vol 9 (1) ◽  
pp. 250
Author(s):  
Débora Teobaldo ◽  
Gustavo Macedo de Mello Baptista
Keyword(s):  
Carbon Sink ◽  
Severity Index ◽  
Burn Severity ◽  
Conservation Units ◽  
Differenced Normalized Burn Ratio ◽  
Before And After ◽  
Distrito Federal ◽  
Para Determinar ◽  
Normalized Burn Ratio ◽  
The Relationship

O objetivo desse trabalho foi avaliar o grau de severidade das queimadas e da perda do sequestro de carbono nas principais Unidades de Conservação do Distrito Federal nos anos de 2010 e 2011. Para determinar o grau de severidade utilizou-se índices espectrais antes e depois da queimada, como o índice de queimada por razão normalizada (NBR) e o índice relativo diferenciado de queimada por razão normalizada (RdNBR). O sequestro de carbono perdido pela queimada foi comparado antes, depois da queimada e na rebrota pelo índice espectral CO2flux. A relação entre a severidade e o sequestro de carbono também foi determinada por meio das imagens de pré-fogo, pós-fogo e da rebrota e a comparação temporal do CO2flux. As regressões obtidas para o ano de 2010 foram bastante de acordo com o esperado, com baixa relação antes da queimada, alta após, e menor na rebrota. Já para 2011, como ocorreram queimadas ao longo de todo o período, não foi possível verificar relações favoráveis.    A B S T R A C T The aim of this study was to assess the burn severity and carbon sink in the Conservation Units at Distrito Federal in the 2010 and 2011. For the burn severity index was used to quantify biomass before and after burning, such as a Normalized Burn Ratio - NBR and relative differenced Normalized Burn Ratio - RdNBR indices. Carbon sink lost by the burning was compared before and after fire by regrowth CO2flux spectral index. The relationship between the burn severity and carbon sink were also made by means the pre, post-fire and regrowth images, and temporal comparison of CO2flux. The regressions obtained for the 2010 were largely in agreement with expectations, with a low pre-fire, after high and low in regrowth. Already in 2011, as fires occurred throughout the period, it was not possible to verify favorable relationships. Keywords: Biomass, burn severity, RdNBR, carbon sink, CO2flux.  

Evaluating the ability of the differenced Normalized Burn Ratio (dNBR) to predict ecologically significant burn severity in Alaskan boreal forests

2008 ◽  
Vol 17 (4) ◽  
pp. 490 ◽  
Author(s):  
Karen A. Murphy ◽  
Joel H. Reynolds ◽  
John M. Koltun
Keyword(s):  
Boreal Forest ◽  
Boreal Forests ◽  
Burn Severity ◽  
Fire Season ◽  
Vegetation Composition ◽  
Management Objectives ◽  
Differenced Normalized Burn Ratio ◽  
Normalized Burn Ratio ◽  
Processing Errors ◽  
The Relationship

During the 2004 fire season ~6.6 million acres (~2.7 million ha) burned across Alaska. Nearly 2 million of these were on National Wildlife Refuge System lands inaccessible from the state’s limited road system. Many fires burned through September, driven by unusually warm and dry temperatures throughout the summer. Using several fires from this season, we assessed the national burn severity methodology’s performance on refuge lands. Six fires, spanning 814 489 acres (329 613 ha), were sampled on five boreal forest refuges. In total, 347 sites were sampled for vegetation composition and ground-based burn severity estimates following the national protocols. The relationship between the differenced Normalized Burn Ratio (dNBR) and composite burn index (CBI) was unexpectedly weak (R2adjusted, 0.11–0.64). The weak relationship was not a result of data or image processing errors, nor of any biotic or abiotic confounding variable. The inconsistent results, and dNBR’s limited ability to discern the ecologically significant differences within moderate and high severity burn sites, indicate that the current methodology does not satisfy key Alaskan boreal forest management objectives.

Comparison of burn severity assessments using Differenced Normalized Burn Ratio and ground data

2005 ◽  
Vol 14 (2) ◽  
pp. 189 ◽  
Author(s):  
Allison E. Cocke ◽  
Peter Z. Fulé ◽  
Joseph E. Crouse
Keyword(s):  
Pinus Ponderosa ◽  
Forest Structure ◽  
Tree Mortality ◽  
Fire Severity ◽  
Basal Area ◽  
Burn Severity ◽  
Burned Areas ◽  
Differenced Normalized Burn Ratio ◽  
Severity Levels ◽  
Normalized Burn Ratio

Burn severity can be mapped using satellite data to detect changes in forest structure and moisture content caused by fires. The 2001 Leroux fire on the Coconino National Forest, Arizona, burned over 18 pre-existing permanent 0.1 ha plots. Plots were re-measured following the fire. Landsat 7 ETM+ imagery and the Differenced Normalized Burn Ratio (ΔNBR) were used to map the fire into four severity levels immediately following the fire (July 2001) and 1 year after the fire (June 2002). Ninety-two Composite Burn Index (CBI) plots were compared to the fire severity maps. Pre- and post-fire plot measurements were also analysed according to their imagery classification. Ground measurements demonstrated differences in forest structure. Areas that were classified as severely burned on the imagery were predominantly Pinus ponderosa stands. Tree density and basal area, snag density and fine fuel accumulation were associated with severity levels. Tree mortality was not greatest in severely burned areas, indicating that the ΔNBR is comprehensive in rating burn severity by incorporating multiple forest strata. While the ΔNBR was less accurate at mapping perimeters, the method was reliable for mapping severely burned areas that may need immediate or long-term post-fire recovery.

scholarly journals A Statistical and Spatial Analysis of Portuguese Forest Fires in Summer 2016 Considering Landsat 8 and Sentinel 2A Data

Environments ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 36 ◽  
Author(s):  
Ana Teodoro ◽  
Ana Amaral
Keyword(s):  
Forest Fires ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Burn Severity ◽  
Landsat 8 ◽  
Fire Event ◽  
Burned Areas ◽  
Area Burned ◽  
Sentinel 2A ◽  
Normalized Burn Ratio

Forest areas in Portugal are often affected by fires. The objective of this work was to analyze the most fire-affected areas in Portugal in the summer of 2016 for two municipalities considering data from Landsat 8 OLI and Sentinel 2A MSI (prefire and postfire data). Different remote sensed data-derived indices, such as Normalized Difference Vegetation Index (NDVI) and Normalized Burn Ratio (NBR), could be used to identify burnt areas and estimate the burn severity. In this work, NDVI was used to evaluate the area burned, and NBR was used to estimate the burn severity. The results showed that the NDVI decreased considerably after the fire event (2017 images), indicating a substantial decrease in the photosynthesis activity in these areas. The results also indicate that the NDVI differences (dNDVI) assumes the highest values in the burned areas. The results achieved for both sensors regarding the area burned presented differences from the field data no higher than 13.3% (for Sentinel 2A, less than 7.8%). We conclude that the area burned estimated using the Sentinel 2A data is more accurate, which can be justified by the higher spatial resolution of this data.

Arab women feelings while seeking information during COVID-19 pandemic: applying PMT constructs

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Asma Alwreikat ◽  
Ahmed Shehata ◽  
Metwaly Ali Mohamed Edakar
Keyword(s):  
Health Information ◽  
Information Seeking ◽  
Arab Countries ◽  
Arab Women ◽  
Structured Interviews ◽  
New Approach ◽  
Content Type ◽  
Perceived Severity ◽  
Study Results ◽  
The Relationship

PurposeThis study investigates the effect of protection motivation theory (PMT) constructs on Arab women's feelings while seeking information during the COVID-19 pandemic.Design/methodology/approachThe study has adopted a mixed-method approach using semi-structured interviews and a questionnaire to explore PMT constructs' impact on women's feelings while seeking information on COVID-19. Several tests, such as standard deviation, mean, skewness, kurtosis and persons, were used to check the reliability of data and inter-relationships between constructs.FindingsThe study results show a significant positive correlation between PMT constructs (perceived vulnerability, perceived severity, response efficacy, self-efficacy and response cost) with the feelings of Arab women during information seeking on COVID-19. However, the relationship between threat appraisal and feelings during information seeking was more substantial than coping appraisal and feelings during information seeking. The researchers hope that this study creates a baseline of cross-cultural studies on PMT constructs' effect on women's feelings while seeking health information.Research limitations/implicationsThe current study was conducted on female participants only. While the study intended to examine Arab women's feelings during information seeking with PMT's application, the results may be affected by other factors that were not considered in the current study. Furthermore, the questionnaire was distributed in three Arab countries, which means that the results cannot be generalized in other geographical contexts. Therefore, similar studies need to be conducted in larger geographical areas as cultural factors may produce different results.Originality/valueThis study explores women's feelings while seeking COVID-19 information using the PMT constructs. As far as we know, this study is the first study to investigate Arab women's feelings while seeking health information during pandemics. PMT utilization is considered a new approach to discover and measure informational needs and feelings associated with it during pandemics.

Colonialism and the Highland Clearances

2017 ◽  
Vol 8 (1) ◽  
pp. 22-48 ◽  
Author(s):  
Iain Mackinnon
Keyword(s):  
Industrial Development ◽  
Comparative Approach ◽  
Indigenous Research ◽  
Internal Colonialism ◽  
New Approach ◽  
A Site ◽  
Relationship Of ◽  
The Relationship ◽  
Imperial State ◽  
Late Modern

This article employs a new approach to studying internal colonialism in northern Scotland during the 18th and 19th centuries. A common approach to examining internal colonial situations within modern state territories is to compare characteristics of the internal colonial situation with attested attributes of external colonial relations. Although this article does not reject the comparative approach, it seeks to avoid criticisms that this approach can be misleading by demonstrating that promoters and managers of projects involving land use change, territorial dispossession and industrial development in the late modern Gàidhealtachd consistently conceived of their work as projects of colonization. It further argues that the new social, cultural and political structures these projects imposed on the area's indigenous population correspond to those found in other colonial situations, and that racist and racialist attitudes towards Gaels of the time are typical of those in colonial situations during the period. The article concludes that the late modern Gàidhealtachd has been a site of internal colonization where the relationship of domination between colonizer and colonized is complex, longstanding and occurring within the imperial state. In doing so it demonstrates that the history and present of the Gaels of Scotland belongs within the ambit of an emerging indigenous research paradigm.

Moderating Role of Gender in the Relationship between Cognitive Errors and Anxiety among Adolescents

2020 ◽  
Vol 4 (1) ◽  
pp. 86-102
Author(s):  
Tasnim Rehna ◽  
Rubina Hanif ◽  
Muhammad Aqeel
Keyword(s):  
Mental Health Problems ◽  
Adolescent Psychopathology ◽  
Future Research ◽  
Cognitive Errors ◽  
Adolescent Anxiety ◽  
Study Results ◽  
The Status ◽  
Manifest Anxiety ◽  
The Relationship

Background: Widespread social paradigms on which the status variances are grounded in any society, gender plays pivotal role in manifestation of mental health problems (Rutter, 2007). A hefty volume of research has addressed the issue in adults nonetheless, little is vividly known about the role of gender in adolescent psychopathology. Sample: A sample of 240 adolescents (125 boys, 115 girls) aging 12-18 years was amassed from various secondary schools of Islamabad with the approval of the Federal Directorate of Education (FDE), relevant authorities of the schools and the adolescents themselves. Instruments: Taylor Manifest Anxiety Scale (Taylor & Spence, 1953) and Children’s Negative Cognitive Errors Questionnaire (CNCEQ) by Leitenberg et al., (1986) were applied in present study. Results: Multiple regression analysis revealed that cognitive errors jointly accounted for 78% of variance in predicting anxiety among adolescents. Findings also exhibited that gender significantly moderated the relationship between cognitive errors and adolescent anxiety. Implications of the findings are discoursed for future research and clinical practice.

RECREATION SPECIALIZATION FOR RUNNERS AND EVENT ATTACHMENT

2020 ◽  
Author(s):  
Isao Okayasu ◽  
Chi-Ok Oh ◽  
Duarte B Morais
Keyword(s):  
Practical Implication ◽  
Event Management ◽  
Attitudes And Behaviors ◽  
The Third ◽  
Study Results ◽  
The World ◽  
Recreation Specialization ◽  
And Behaviors ◽  
The Relationship ◽  
Predictive Relationship

Running is one of the most popular activities in the world. Runners’ attitudes and behaviors vary depending on their running style. This study aims to construct different measures of running specialization based on the theory of specialization. This study also tests a runner’s stage of specialization segmentation based on recreation specialization and examines the predictive relationship between a runner’s specialization and event attachment. Three groups of sampling data assess the performance of diverse specialization measures for running in three marathon events. First, two surveys were conducted with marathon participants to assess the performance of diverse specialization measures for runners. Second, the third dataset was used to examine the relationship between a runner’s recreation specialization and event attachment.The study results showed that the 15 measures of specialization showed a good fit to the data. Our research showed how runners’ recreation specialization is connected to their event attachment. In addition, this study suggested event management for subdivisions of runners. Its practical implication is that recreation specialization for running can help us understand event attachment.

Motivating and Retaining Festival Patronage

2020 ◽  
Vol 24 (4) ◽  
pp. 447-461
Author(s):  
Michelle (Myongjee) Yoo ◽  
Miranda Kitterlin-Lynch ◽  
Bomin Kim
Keyword(s):  
Structural Equation ◽  
Customer Relationship ◽  
Equation Modeling ◽  
Organization And Management ◽  
Customer Relationship Marketing ◽  
Study Results ◽  
And Behavior ◽  
The Relationship ◽  
Self Administered Questionnaire ◽  
Theoretical Foundations

Globally, festivals and host communities face increased competition each year from one another and from the myriad of alternate entertainment options. To remain competitive, festival organizers must fully understand what keeps festival attendees coming back year after year. Festivalscape has been an emerging concept of value in this arena, and previous studies have found that festivalscape has an effect on the attendees' emotion and behavior that influences their overall perceived value of the festival. The purpose of this study is to examine the relationship between festivalscape and the attendees' motivation, satisfaction, and loyalty. A self-administered questionnaire was developed and a structural equation modeling (SEM) was employed to test the proposed hypotheses. Study results support the hypotheses, indicating the importance of using festivalscape factors for festival organization and management and effective customer relationship marketing. Further, this study provides academic contributions to theoretical foundations by confirming the effects of these factors. This study also provides practical implications for managing festivals effectively and successfully.

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