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1.
Wildland fire creates a complex relationship between federal agencies and public stakeholders. Questions surrounding the public's role in federal wildland fire management point to broader questions about the relationships among scientists, policymakers, federal agencies, and the public. In this article we report on a project to provide information about the key components of federal policies that govern wildland fire management. The goal is to enhance the decision support capabilities of a geographic information system (GIS)-based fire risk model and the capacity of users to interpret the outputs of the model from a fire policy perspective. We conclude by making recommendations for how this and other such tools might be refined to improve and expand policy interactions among government land and resource management agencies, scientists, and the public.  相似文献   

2.
Rothermel's model is the most widely used fire behaviour model in wildland fire research and management. It is a complex model that considers 17 input variables describing fuel type, fuel moisture, terrain and wind. Uncertainties in the input variables can have a substantial impact on the resulting errors and have to be considered, especially when the results are used in spatial decision making. In this paper it is shown that the analysis of uncertainty propagation can be carried out with the Taylor series method. This method is computationally cheaper than Monte Carlo and offers easy-to-use, preliminary sensitivity estimations.  相似文献   

3.
Development of efficient forest wildfire policies requires an understanding of the underlying reasons behind forest fire occurrences. Globally, there is a close relationship between forest wildfires and human activities; most wildfires are human events due to negligence (e.g., agricultural burning escapes) and deliberate actions (e.g., vandalism, pyromania, revenge, land use change attempts). We model the risk of wildfire as a function of the spatial pattern of urban development and the abandonment/intensity of agricultural and forestry activities, while controlling for biophysical and climatic factors. We use a count data approach to model deliberately set fires in Galicia, N.W. Spain, where wildfire is a significant threat to forest ecosystems, with nearly 100,000 wildfires recorded during a thirteen-year period (1999–2011). The spatial units of analysis are more than 3600 parishes. Data for the human influences are derived from fine-resolution maps of wildland–urban interface (WUI), housing spatial arrangements, road density, forest ownership, and vegetation type. We found wildfire risk to be higher where there are human populations and development/urbanisation pressure, as well as in unattended forest areas due to both rural exodus and a fragmented forest ownership structure that complicates the profitability of forestry practices. To better help direct management efforts, parameter estimates from our model were used to predict wildfire counts under alternative scenarios that account for variation across space on future land-use conditions. Policies that incentivize cooperative forest management and that constrain urban development in wildlands at hotspot fire locations are shown to reduce wildfire risk. Our results highlight the need for spatially targeted fire management strategies.  相似文献   

4.
Wildfires create a risk to pedestrians traveling through rural areas, because they might not be aware of the presence of a wildfire or its direction and rate of spread until is too late to successfully evacuate. In wildland areas of southern San Diego County, immigrants crossing the U.S.–Mexico border and border security agents are particularly at risk to wildfires. The objective of this study is to develop a framework of analysis and associated tools for examining the combined behavior of wildfires and pedestrian mobility to assess the potential threat of fire to pedestrians in wildland areas. Outputs from a geographic information system (GIS) overlay model for determining potentially dangerous fire zones, the Wildland–Urban Interface Evacuation (WUIVAC) model, and a model of pedestrian mobility in wildland areas were combined to generate wildfire risk to pedestrian maps. The key technical contributions of the study are the development and testing of the pedestrian mobility model and the framework and logic for integrating the results of three GIS-based models. The applied geography contribution is the testing of two scenarios of high risk from wildfires to pedestrians within the U.S.–Mexico border zone of San Diego County, California.

The study results show that the travel times calculated by the pedestrian mobility model appear to be realistic and are affected by the terrain and vegetation characteristics of a study site, whereas the evacuation trigger buffers (ETBs) from WUIVAC are mostly influenced by the wind speed and direction parameters of the FlamMap fire spread model. A moderate fire danger to pedestrians in the most remote wildland locations of the study area is determined. The scenario test results suggest that if a wildfire occurs within 2 km (extreme southwesterly winds) or 6 km (extreme northeasterly wind) of pedestrians in the worst case location within the San Diego border region they would likely not have a sufficient amount of time to reach a nearby safety zone.  相似文献   

5.
Despite wildfire being an important regulator of dryland ecosystems, uncontrolled wildfire can be harmful to both forest ecosystems and human society, and wildfire prevention and control continue to raise worldwide concern. Wildfire management depends on knowledge of wildfire ignitions, both for cause and location. The regimes and factors influencing wildfire ignition have been studied at length. Humans have a profound effect on fire regimes and human activity is responsible for igniting the largest number of fires in our study area. Understanding the spatial patterns of ignitions is foremost to achieving efficiency in wildfire prevention. Previous studies mainly concentrate on overall wildfire risk integrating numerous factors simultaneously, yet the importance of human factors on ignition has not received much attention. In this study, we mapped human accessibility to explore the influence of human activity on wildfire ignition in a simple and straightforward way. A Bayesian weights-of-evidence (WofE) method was developed based on fire hotspots in China's Yunnan province extracted from satellite images and verified as known wildfires for the period 2007–2013. We considered a set of factors that impact fire ignition as associated with human accessibility: the locations of settlements, roads, water and farmland susceptible to human wildfire ignition. Known points of likely wildfire ignition were selected as training samples and all suspected thematic maps of the factors were taken as explanatory layers. Next, the weights of each layer in terms of its explanatory power were computed and used to generate evidence based on a threshold to pass a statistical test. The conditional independence (CI) of each layer was checked with the Agterberg-Cheng test. Finally, the posterior probability was calculated and its precision validated using samples of both presence and absence by withheld validation data. A comparison of WofE models was made to test the predictability. Results show proximity to villages, roads and farmland are strongly associated with human wildfire ignition and that wildfire more often occurs at an intermediate distance from high-density human activity. The WofE method proved more powerful than logistic regression, improving predictive accuracy by 10% and was more straightforward in presenting the association of dependence and independence. In addition, WofE with 1000 m buffer bands is more robust in predicting human wildfire ignition risk than binary or 100 m buffers for the ecoregion studied. Our results are significant for advising practical wildfire management and resource allocation, evaluation of human ignition control and also provides a foundation for future efforts toward integrated wildfire prediction.  相似文献   

6.
Effective wildfire management is an essential part of forest firefighting strategies to minimize damage to land resources and loss of human lives. Wildfire management tools often require a large number of computing resources at a specific time. Such computing resources are not affordable to local fire agencies because of the extreme upfront costs on hardware and software. The emerging cloud computing technology can be a cost- and result-effective alternative. The purpose of this paper is to present the development and the implementation of a state-of-the-art application running in cloud computing, composed of a wildfire risk and a wildfire spread simulation service. The two above applications are delivered within a web-based interactive platform to the fire management agencies as Software as a Service (SaaS). The wildfire risk service calculates and provides daily to the end-user maps of the hourly forecasted fire risk for the next 112 hours in high spatiotemporal resolution, based on forecasted meteorological data. In addition, actual fire risk is calculated hourly, based on meteorological conditions provided by remote automatic weather stations. Regarding the wildfire behavior simulation service, end users can simulate the fire spread by simply providing the ignition point and the projected duration of the fire, based on the HFire algorithm. The efficiency of the proposed solution is based on the flexibility to scale up or down the number of computing nodes needed for the requested processing. In this context, end users will be charged only for their consumed processing time and only during the actual wildfire confrontation period. The system utilizes both commercial and open source cloud resources. The current prototype is applied in the study area of Lesvos Island, Greece, but its flexibility enables expansion in different geographical areas.  相似文献   

7.
8.
Wildfires are widely reviewed as key inputs to Mediterranean ecosystems. However, research is often flawed by major biases. (1) The approach adopted by most planners focusing on forest fires dismisses the human dimension of fire as a component of agricultural production systems. (2) The Wildland–Urban Interface (WUI) concept postulates that cities and wildlands/wildfires are, and should remain, worlds apart, a statement whose truth is increasingly questioned by recent disastrous “urban wildfires”. (3) The Mediterranean Basin as a fire-prone area is all the more fantasized, as it is almost never studied as a whole.The present paper takes a critical view of city–wildland/wildfire interrelationships through a large-scale study of the Mediterranean Basin based on MODIS MCD12Q1 (Land Cover Type) and MCD45A1 (Burned Area Product) data collected between 2001 and 2013. The Mediterranean is an ideal place to investigate, as its human-dominated and urbanized landscapes are known to be extremely vulnerable to fire hazards. Data processing reveals that (wild)fires and cities maintain indissoluble ties, as if both elements could not be considered mutually exclusive on a geographical basis. Urban sprawl, reduced rural autonomies, changes in forest covers, old agricultural practices, and military conflicts provide the framework for an extended mitigation process challenging the WUI concept as a space divider.  相似文献   

9.
This paper focuses on spatial distribution of long-term fire patterns versus physical and anthropogenic elements of the environment that determine wildfire dynamics in Greece. Logistic regression and correspondence analysis were applied in a spatial database that had been developed and managed within a Geographic Information System. Cartographic fire data were statistically correlated with basic physical and human geography factors (geomorphology, climate, land use and human activities) to estimate the degree of their influence at landscape scale. Land cover types of natural and agricultural vegetation were the most influential factors for explaining landscape wildfire dynamics in conjunction with topography and grazing.  相似文献   

10.
The number of people living in wildfire-prone wildland–urban interface (WUI) communities is on the rise. However, no prior study has investigated wildfire-induced residential relocation from WUI areas after a major fire event. To provide insight into the association between sociodemographic and sociopsychological characteristics and wildfire-related intention to move, we use data from a survey of WUI residents in Boulder and Larimer counties, Colorado. The data were collected 2 months after the devastating Fourmile Canyon fire destroyed 169 homes and burned more than 6,000 acres of public and private land. Although this study is working with a small migrant sample, logistic regression models demonstrate that survey respondents intending to move in relation to wildfire incidence do not differ sociodemographically from their nonmigrant counterparts. They do, however, show significantly higher levels of risk perception. Investigating destination choices shows a preference for short-distance moves.  相似文献   

11.
This article explores the potential impact of training and employment with wildfire management agencies on the retention of Indigenous fire knowledge. It focuses on the comparative knowledge and experiences of Indigenous Elders, cultural practitioners, and land stewards in connection with “modern” political constructs of fire in New South Wales and Queensland, Australia, and California in the United States of America. This article emphasises the close link between cross-cultural acceptance, integration of Indigenous and agency fire cultures, and the ways in which knowledge types are shared or withheld. While agency fire fighting provides an opportunity for Indigenous people to connect and care for country, it simultaneously allows for the breaking of traditional rules surrounding what knowledge is shared with whom in the context of Indigenous cultural burning. By highlighting how privilege intersects with ethnicity, class, gender and age, this article demonstrates how greater cross-cultural acceptance could aid ongoing debates on how to coexist with wildfire today.  相似文献   

12.
Increases in wildfire frequency and extent in rangelands pose a growing threat to private property and ecosystem health. The state of Idaho, USA, recently promoted rangeland fire protection associations (RFPAs)—nonprofit organizations of local citizens who contribute to firefighting efforts on public rangelands—as one way to mitigate rangeland wildfire risk. This study used in-depth interviews with RFPA members and land management professionals to explore the local circumstances that influenced the establishment and functioning of one RFPA. Results indicate that intergenerational ties to “working the land,” existing reciprocity among neighbors, a culture of self-reliance, and informal social networks all contributed to RFPA formation and functioning. Interaction between RFPA members and professionals improved their relationships and promoted shared understandings about wildfire response. We conclude by discussing conditions that might enable or inhibit RFPAs in other areas and how our findings advance research on adapting mitigation programs to local context.  相似文献   

13.
This paper explores whether fundamental differences exist between urban and rural vulnerability to climate-induced changes in the fire regime of interior Alaska. We further examine how communities and fire managers have responded to these changes and what additional adaptations could be put in place. We engage a variety of social science methods, including demographic analysis, semi-structured interviews, surveys, workshops and observations of public meetings. This work is part of an interdisciplinary study of feedback and interactions between climate, vegetation, fire and human components of the Boreal forest social–ecological system of interior Alaska. We have learned that although urban and rural communities in interior Alaska face similar increased exposure to wildfire as a result of climate change, important differences exist in their sensitivity to these biophysical, climate-induced changes. In particular, reliance on wild foods, delayed suppression response, financial resources and institutional connections vary between urban and rural communities. These differences depend largely on social, economic and institutional factors, and are not necessarily related to biophysical climate impacts per se. Fire management and suppression action motivated by political, economic or other pressures can serve as unintentional or indirect adaptation to climate change. However, this indirect response alone may not sufficiently reduce vulnerability to a changing fire regime. More deliberate and strategic responses may be required, given the magnitude of the expected climate change and the likelihood of an intensification of the fire regime in interior Alaska.  相似文献   

14.
Wildfires cause enormous damage worldwide, particularly in Victoria, Australia, with growing populations in fire-prone ecosystems. Broad-scale prescribed burning is an established, yet controversial, wildfire management policy in Victoria and Australia. But does broad-scale prescribed burning reduce fire damage? The answer depends on how damage is measured. We propose that different perceptions about the efficacy of broad-scale prescribed burning derive from different disciplinary measures of damage (e.g., biodiversity, area burned, or fatalities). Although broad-scale prescribed burning reduces subsequent wildfire size, there is little evidence that it saves human lives and homes. Evidence suggests that small-scale fuel reduction may be more effective at saving lives. The prescribed burning debate might be better focused on what damage we wish to limit, and which measures are most effective at limiting this damage. In this context, the current policy focus on broad-scale prescribed burning targets may distract efforts from more effective lifesaving strategies.  相似文献   

15.
This article presents a case study of risk perception and decision making regarding the former nuclear test site of Bikini Atoll in the Marshall Islands. This example demonstrates how people use combinations of scientific and anecdotal evidence to consider whether places are “really safe.” Furthermore, the article examines how scientific studies of risk operate as cultural systems and how a lack of dialogue and understanding across cultural systems can confuse discussions about risk and affect the development of places. The study is based on interviews with still‐exiled Bikinians as well as with workers and visitors on Bikini Atoll.  相似文献   

16.
Wildfires have long been an important environmental concern in Florida. Recent wildfires along the urban-rural interface of large cities in Florida have pointed to the need for an increased understanding of the physical and biological mechanisms that govern wildfire occurrence. Increased awareness of the relationships between global climate changes occurring in the tropics and their teleconnections outside the tropics dictate a reevaluation of the role of phenomena such as El Niño-Southern Oscillation on the risk of wildfire. One simple way of illustrating the relationship between ENSO and wildfire occurrence is the use of an Analysis of Variance (ANOVA) on wildfire data that has been categorized according to ENSO status (El Niño, La Niña, and neutral years). This research shows that a statistically significant relationship exists between ENSO conditions and annual wildfire occurrence in Florida when ENSO conditions are treated as a potential precursor to wildfire conditions. In particular, a statistically significant relationship exists between both acreage burned and average fire size, when the data are separated into El Niño and La Niña categories according to the previous year's ENSO status. This supports the idea that the climate from previous years has a measurable effect upon fire statistics in the years following the climate measurements, and that it may be possible to create a regional fire prediction model that incorporates ENSO information. [Key words: wildfire, natural hazards, ANOVA, Florida, ENSO.]  相似文献   

17.
There is now increasing agreement that the uncertainty associated with spatial information should be represented to users in a manner that is comprehensive and unambiguous. To assist with this task, researchers have developed a variety of methods to portray spatial uncertainty. While there has been some testing of the effectiveness of these displays, the possible effects of such representations on decision‐making have not yet been thoroughly investigated. Indeed, studies from the psychological literature indicate that people do not always make the same decisions when presented with the same information, and they can also be sensitive to the effects of presentation, task, and context. This paper examines how the use of four different methods to represent positional uncertainty can affect spatial decision‐making. The authors found that extremely significant differences in participants' responses were exhibited, depending on the manner in which positional uncertainty was displayed, although little difference was observed in the ability of the participants to comprehend the four display methods. In addition, strong preferences were recorded for certain representations over others.  相似文献   

18.
The paper investigates whether the methods chosen for representing uncertain geographic information aid or impair decision-making in the context of wildfire hazard. Through a series of three human subject experiments, utilizing 180 subjects and employing increasingly difficult tasks, this research evaluates the effect of five different visualizations and a text-based representation on decision-making under uncertainty. Our quantitative experiments focus specifically on the task of decision-making under uncertainty, rather than the task of reading levels of uncertainty from the map. To guard against the potential for generosity and risk seeking in decision-making under uncertainty, the experimental design uses performance-based incentives. The experiments showed that the choice of representation makes little difference to performance in cases where subjects are allowed the time and focus to consider their decisions. However, with the increasing difficulty of time pressure, subjects performed best using a spectral color hue-based representation, rather than more carefully designed cartographic representations. Text-based and simplified boundary encodings were among the worst performers. The results have implications for the performance of decision-making under uncertainty using static maps, especially in the stressful environments surrounding an emergency.  相似文献   

19.
To what extent were Australian vegetation patterns in 1788 a product of human activity? Pollen and charcoal evidence which addresses this question is reviewed. I discuss the nature of the evidence, particularly the difficulties involved in establishing relationships between charcoal and fire history, and between fire history and human activity. I then address the broader question from the perspectives of both time and space by examining three key periods which might be expected to provide relevant evidence: (i) the time of initial human colonisation of the continent; (ii) the late Holocene, when Aboriginal population densities are thought to have increased substantially; and (iii) the last 200 years, when Aboriginal influences on the landscape have been mostly removed. Impacts are likely to have been different in different environments, with vegetation types vulnerable to fire showing the most marked changes. I conclude with a discussion of ways alternative interpretations have been utilised by competing groups in land management debates.  相似文献   

20.
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