scholarly journals Modeling anthropogenic and natural fire ignitions in an inner-alpine valley

Author(s):  
Giorgio Vacchiano ◽  
Cristiano Foderi ◽  
Roberta Berretti ◽  
Enrico Marchi ◽  
Renzo Motta

Abstract. Modelling and assessing the factors that drive forest fire ignitions is critical for fire prevention and sustainable ecosystem management. In southern Europe, the anthropogenic component of wildland fire ignitions is especially relevant. In the Alps, however, the role of fire as a component of disturbance regimes in forest and grassland ecosystems is poorly known. The aim of this work is to model the probability of fire ignition for an alpine region in Italy using a regional wildfire archive (1995–2009) and MaxEnt modeling. We analyzed separately: i) winter forest fires; ii) winter fires on grasslands and fallow land; iii) summer fires. Predictors were related to morphology, climate, and land use; distance from infrastructures, number of farms, and number of grazing animals were used as proxies for the anthropogenic component; collinearity among predictors was reduced by a Principal Component Analysis. 30 % of ignitions occurred in agricultural areas, 24 % in forests. Ignitions peaked in the late winter–early spring. Negligence from agro-silvicultural activities was the main cause of ignition (64 %); lightning accounted for 9 % of causes across the study timeframe, but increased from 6 % to 10 % between the first and second period of analysis. Models for all groups of fire had a high goodness of-fit (AUC 0.90–0.95). Temperature was proportional to the probability of ignition, and precipitation inverse proportional. Proximity from infrastructures had an effect only on winter fires, while the density of grazing animals had a remarkably different on summer (positive correlation) and winter (negative) fires. Implications are discussed regarding climate change, fire regime changes, and silvicultural prevention. Such spatially explicit approach allows to carry out spatially targeted fire management strategies, and may assist in developing better fire management plans.

2018 ◽  
Vol 18 (3) ◽  
pp. 935-948 ◽  
Author(s):  
Giorgio Vacchiano ◽  
Cristiano Foderi ◽  
Roberta Berretti ◽  
Enrico Marchi ◽  
Renzo Motta

Abstract. Modeling and assessing the factors that drive forest fire ignitions is critical for fire prevention and sustainable ecosystem management. In southern Europe, the anthropogenic component of wildland fire ignitions is especially relevant. In the Alps, however, the role of fire as a component of disturbance regimes in forest and grassland ecosystems is poorly known. The aim of this work is to model the probability of fire ignition for an Alpine region in Italy using a regional wildfire archive (1995–2009) and MaxEnt modeling. We analyzed separately (i) winter forest fires, (ii) winter fires on grasslands and fallow land, and (iii) summer fires. Predictors were related to morphology, climate, and land use; distance from infrastructures, number of farms, and number of grazing animals were used as proxies for the anthropogenic component. Collinearity among predictors was reduced by a principal component analysis. Regarding ignitions, 30 % occurred in agricultural areas and 24 % in forests. Ignitions peaked in the late winter–early spring. Negligence from agrosilvicultural activities was the main cause of ignition (64 %); lightning accounted for 9 % of causes across the study time frame, but increased from 6 to 10 % between the first and second period of analysis. Models for all groups of fire had a high goodness of fit (AUC 0.90–0.95). Temperature was proportional to the probability of ignition, and precipitation was inversely proportional. Proximity from infrastructures had an effect only on winter fires, while the density of grazing animals had a remarkably different effect on summer (positive correlation) and winter (negative) fires. Implications are discussed regarding climate change, fire regime changes, and silvicultural prevention. Such a spatially explicit approach allows us to carry out spatially targeted fire management strategies and may assist in developing better fire management plans.


Author(s):  
Eric S. Kasischke ◽  
David L. Verbyla

Fire is ubiquitous throughout the global boreal forest (Wein 1983, Payette 1992, Goldammer and Furyaev 1996, Kasischke and Stocks 2000). The inter- and intra-annual patterns of fire in this biome depend on several interrelated factors, including the quantity and quality of fuel, fuel moisture, and sources of ignition. Fire cycles in different boreal forest types vary between 25 and >200 years (Heinselman 1981, Yarie 1981, Payette 1992, Conard and Ivanova 1998). Although the increased presence of humans in some regions of boreal forest has undoubtedly changed the fire regime (DeWilde 2003), natural fire is still a dominant factor in ecosystem processes throughout this biome. Boreal forest fires are similar to those of other forests in that they vary between surface and crown fires, depending on forest type and climatic factors. Surface fires kill and consume most of the understory vegetation, as well as portions of the litter or duff lying on the forest floor, resulting in varying degrees of mortality of canopy and subcanopy trees. Crown fires consume large amounts of the smaller plant parts (or fuels) present as leaves, needles, twigs, and small branches and kill all trees. These fires are important in initiating secondary succession (Lutz 1956, Heinselman 1981, Van Cleve and Viereck 1981, Van Cleve et al. 1986, Viereck 1983, Viereck et al. 1986). Unlike fires in other forest types, smoldering ground fires in the boreal forest can combust a significant fraction of the deep organic (fibric and humic) soils in forests overlying permafrost (Dyrness and Norum 1983, Landhauesser and Wein 1993, Kasischke et al. 2000a, Miyanishi and Johnson 2003). During periods of drought, when water tables are low, or prior to spring thaw, organic soils in peatlands can become dry enough to burn, as well (Zoltai et al. 1998, Turetsky and Wieder 2001, Turetsky et al. 2002).


2013 ◽  
Vol 22 (3) ◽  
pp. 296 ◽  
Author(s):  
M. Vanesa Moreno ◽  
Emilio Chuvieco

The concept of fire regime refers to a variety of fire characteristics occurring at a given place and period of time. Understanding fire regimes is relevant to fire ecology and fire management because it provides a better understanding of effects of fire as well as the potential effects of different future scenarios. Recent changes in the traditional fire regimes linked to climate and socioeconomic transformations in European Mediterranean areas have influenced fire regimes and their effects on both ecosystems and people. This paper presents a methodology for characterising fire regimes based on historical fire statistics. The analysis includes three dimensions: density, seasonality and interannual variability. The raw records were pre-processed to eliminate errors, and a principal component analysis was performed to identify the primary factors involved in the variation. A cluster analysis was then used to define the fire regimes. Approximately 38% of the spatial cells examined were found to have significant fire activity, but in spite that fires are important in these areas, fire activity showed a high interannual variability. Four fire regimes in the Spanish peninsular territory were described in terms of the density and seasonality of fire activity.


2007 ◽  
Vol 16 (1) ◽  
pp. 81 ◽  
Author(s):  
A. H. W. Seydack ◽  
S. J. Bekker ◽  
A. H. Marshall

Over the last seven decades, the Mediterranean-type shrublands of the Swartberg Mountain Range (170 856 ha), South Africa, have been subject to divergent fire management policies. Management objectives sequentially focused on grazing, fire control, water and biodiversity conservation during successive fire management periods. The aim of the present study was to explore the factors that determined the prevailing fire regime patterns during these fire management periods. This was considered particularly relevant in view of the ongoing debate on the relative role of fuel characteristics versus weather and ignition rates in shaping fire regime patterns. The extent of burning followed climatic cycles of alternating periods of relatively high temperatures and summer rainfall with cooler periods and increased winter rainfall. Accordingly, fires occurred more extensively during the former and were largely unaffected by the absence or presence of fire control measures. Fire return intervals were strongly inversely related to productivity of the vegetation. Long-term means between 30 and 55 years were found to apply in low-altitude xeric shrubland types. Corresponding fire return intervals were generally shorter in mesic shrublands at mid to high altitudes (15–30 years). Proteoid shrublands younger than 6 years were practically non-flammable. Two basic fire regime scenarios were identified. Fire regime patterns in xeric shrublands at lower altitudes were largely controlled by the rate of fuel accumulation, whereas climatically controlled ignition frequencies and fire climate constituted the dominant controls in proteoid shrublands at mid to high altitudes. The spatiotemporal distribution of fire regime parameters (fire frequencies, season, size and intensity) as recorded in the present study for the Swartberg Mountain Range under natural fire zone management (predominance of lightning fires since 1980), appeared to be conducive to the maintenance of biodiversity according to our current understanding of the fire–vegetation system.


Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Willem A. Nieman ◽  
Brian W. van Wilgen ◽  
Alison J. Leslie

Abstract Background Fire is an important process that shapes the structure and functioning of African savanna ecosystems, and managers of savanna protected areas use fire to achieve ecosystem goals. Developing appropriate fire management policies should be based on an understanding of the determinants, features, and effects of prevailing fire regimes, but this information is rarely available. In this study, we report on the use of remote sensing to develop a spatially explicit dataset on past fire regimes in Majete Wildlife Reserve, Malawi, between 2001 and 2019. Moderate Resolution Imaging Spectroradiometer (MODIS) images were used to evaluate the recent fire regime for two distinct vegetation types in Majete Wildlife Reserve, namely savanna and miombo. Additionally, a comparison was made between MODIS and Visible Infrared Imager Radiometer Suite (VIIRS) images by separately evaluating selected aspects of the fire regime between 2012 and 2019. Results Mean fire return intervals were four and six years for miombo and savanna vegetation, respectively, but the distribution of fire return intervals was skewed, with a large proportion of the area burning annually or biennially, and a smaller proportion experiencing much longer fire return intervals. Variation in inter-annual rainfall also resulted in longer fire return intervals during cycles of below-average rainfall. Fires were concentrated in the hot-dry season despite a management intent to restrict burning to the cool-dry season. Mean fire intensities were generally low, but many individual fires had intensities of 14 to 18 times higher than the mean, especially in the hot-dry season. The VIIRS sensors detected many fires that were overlooked by the MODIS sensors, as images were collected at a finer scale. Conclusions Remote sensing has provided a useful basis for reconstructing the recent fire regime of Majete Wildlife Reserve, and has highlighted a current mismatch between intended fire management goals and actual trends. Managers should re-evaluate fire policies based on our findings, setting clearly defined targets for the different vegetation types and introducing flexibility to accommodate natural variation in rainfall cycles. Local evidence of the links between fires and ecological outcomes will require further research to improve fire planning.


2021 ◽  
pp. 096973302098175
Author(s):  
Olivia Numminen ◽  
Kasper Konings ◽  
Roelant Claerhout ◽  
Chris Gastmans ◽  
Jouko Katajisto ◽  
...  

Background: Moral courage as a part of nurses’ moral competence has gained increasing interest as a means to strengthen nurses acting on their moral decisions and offering alleviation to their moral distress. To measure and assess nurses’ moral courage, the development of culturally and internationally validated instruments is needed. Objective: The objective of this study was to validate the Dutch-language version of the four-component Nurses’ Moral Courage Scale originally developed and validated in Finnish data. Research design: This methodological study used non-experimental, cross-sectional exploratory design. Participants and research context: A total of 559 nurses from two hospitals in Flanders, Belgium, completed the Dutch-language version of the Nurses’ Moral Courage Scale. Ethical considerations: Good scientific inquiry guidelines were followed throughout the study. Permission to translate the Nurses’ Moral Courage Scale was obtained from the copyright holder, and the ethical approval and permissions to conduct the study were obtained from the participating university and hospitals, respectively. Findings: The four-component 21-item, Dutch-language version of the Nurses’ Moral Courage Scale proved to be valid and reliable as the original Finnish Nurses’ Moral Courage Scale. The scale’s internal consistency reliability was high (0.91) corresponding with the original Nurses’ Moral Courage Scale validation study (0.93). The principal component analysis confirmed the four-component structure of the original Nurses’ Moral Courage Scale to be valid also in the Belgian data explaining 58.1% of the variance. Confirmatory factor analysis based on goodness-of-fit indices provided evidence of the scale’s construct validity. The use of a comparable sample of Belgian nurses working in speciality care settings as in the Finnish study supported the stability of the structure. Discussion and conclusion: The Dutch-language version of the Nurses’ Moral Courage Scale is a reliable and valid instrument to measure nurses’ self-assessed moral courage in speciality care nursing environments. Further validation studies in other countries, languages and nurse samples representing different healthcare environments would provide additional evidence of the scale’s validity and initiatives for its further development.


1999 ◽  
Vol 21 (1) ◽  
pp. 39 ◽  
Author(s):  
AB Craig

This paper examines a range of environmental, research and practical issues affecting fire management of pastoral lands in the southern part of the Kimberley region in Western Australia. Although spinifex grasslands dominate most leases, smaller areas of more productive pastures are crucially important to many enterprises. There is a lack of local documentation of burning practices during traditional Aboriginal occupation; general features of the fire regime at that time can be suggested on the basis of information from other inland areas. Definition of current tire regimes is improving through interpretation of NOAA-AVHRR satellite imagery. Irregular extensive wildfires appear to dominate, although this should be confirmed by further accumulation, validation and analysis of fire history data. While these fires cause ma,jor difficulties. controlled burn~ng is a necessary part of station management. Although general management guidelines have been published. local research into tire-grazing effects has been very limited. For spinifex pastures, reconimendations are generally consistent with those applying elsewhere in northern Australia. They favour periodic burning of mature spinifex late in the year, before or shortly after the arrival of the first rains, with deferment of grazing. At that time. days of high fire danger may still be expected and prediction of fire behaviour is critical to burning decisions. Early dry-season burning is also required for creating protective tire breaks and to prepare for burning later in the year. Further development of tools for predicting fire behaviour, suited to the discontinuous fuels characteristic of the area, would be warranted. A range of questions concerning the timing and spatial pattern of burning, control of post-fire grazing, and the economics of fire management, should be addressed as resources permit. This can be done through a combination of opportunistic studies, modelling and documentation of local experience. The development of an expert system should be considered to assist in planning and conducting burning activities. Key words: Kimberley, fire regimes, fire management, pastoralism, spinifex


2016 ◽  
Vol 9 (4) ◽  
pp. 1 ◽  
Author(s):  
Nooraini Othman

<p class="apa">The aim of this study is to explore the characteristics of innovative personality among teachers in Malaysia. Samples of the research were randomly selected among secondary school teachers in three districts in Malaysia. Research instrument was self-developed by the researchers based on interviews carried out with some resource persons who are both experts and authoritative in their fields, as well as through literature review. A pilot study was carried out among 30 respondents. Cronbach’s Alpha value for the whole instrument is .952, indicating that it is reliable and suitable for actual data collection. A total of 484 sets of questionnaires were completed and gathered to form the data for this research. The data were then analysed using an advanced statistical method called Principal Component Analysis (PCA). Findings of the research concluded three constructs, namely, Leadership, Openness and Braveness. The constructs were labelled based on groups of items which were formed as a result of the PCA analysis. Meanwhile, Confirmatory Factor Analysis (CFA) was used to validate each dimension and to analyse the coherence of data based on model hypothesis. The findings of CFA indicated the goodness-of-fit values of the revised model, as follows: CMIN/DF=2.56; CFI=.935; and RMSEA=.057; with each figure above the threshold value. <strong></strong></p>


1993 ◽  
Vol 69 (3) ◽  
pp. 290-293 ◽  
Author(s):  
Brian J. Stocks

The looming possibility of global warming raises legitimate concerns for the future of the forest resource in Canada. While evidence of a global warming trend is not conclusive at this time, governments would be wise to anticipate, and begin planning for, such an eventuality. The forest fire business is likely to be affected both early and dramatically by any trend toward warmer and drier conditions in Canada, and fire managers should be aware that the future will likely require new and innovative thinking in forest fire management. This paper summarizes research activities currently underway to assess the impact of global warming on forest fires, and speculates on future fire management problems and strategies.


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