An alternative fire regime zonation for Canada

2012 ◽  
Vol 21 (8) ◽  
pp. 1052 ◽  
Author(s):  
Yan Boulanger ◽  
Sylvie Gauthier ◽  
Philip. J. Burton ◽  
Marie-Andrée Vaillancourt

The ability of national and multipurpose ecological classification systems to provide an optimal zonation for a fire regime is questionable. Using wildfire (>1 ha) point data for the 1980–99 period, we defined zones with a homogeneous fire regime (HFR) across Canada and we assessed how these differ from the National Ecological Framework for Canada (NEFC) units of corresponding scale, i.e. ecoprovinces. Two HFR zonations were produced through spatially constrained clustering of (i) 1600-km2 cells and (ii) the smallest units of the NEFC system, i.e. ecodistricts, using attributes for natural and anthropogenic fires. Thirty-three HFR zones were identified. HFR zonations showed smaller differences among each other than with NEFC ecoprovinces. Comparisons with ecoprovinces suggested general agreement of generalised fire regime values with HFR zones but with poor zone boundary correspondence. Ecoprovince zonation led to an overgeneralisation of fire regime estimates with less variation captured than by the HFR zonations, especially that using gridded fixed-area cells. Estimates of fire-return interval strongly differed between a priori and HFR zonations. The use of large-scale NEFC units or a zonation using its smallest units may constrain our ability to accurately quantify and portray fire regime variability across the country. The alternative empirical HFR zonation using gridded cells refines the location and nature of fire risk.

2008 ◽  
Vol 363 (1498) ◽  
pp. 1737-1746 ◽  
Author(s):  
Daniel C Nepstad ◽  
Claudia M Stickler ◽  
Britaldo Soares- Filho ◽  
Frank Merry

Some model experiments predict a large-scale substitution of Amazon forest by savannah-like vegetation by the end of the twenty-first century. Expanding global demands for biofuels and grains, positive feedbacks in the Amazon forest fire regime and drought may drive a faster process of forest degradation that could lead to a near-term forest dieback. Rising worldwide demands for biofuel and meat are creating powerful new incentives for agro-industrial expansion into Amazon forest regions. Forest fires, drought and logging increase susceptibility to further burning while deforestation and smoke can inhibit rainfall, exacerbating fire risk. If sea surface temperature anomalies (such as El Niño episodes) and associated Amazon droughts of the last decade continue into the future, approximately 55% of the forests of the Amazon will be cleared, logged, damaged by drought or burned over the next 20 years, emitting 15–26 Pg of carbon to the atmosphere. Several important trends could prevent a near-term dieback. As fire-sensitive investments accumulate in the landscape, property holders use less fire and invest more in fire control. Commodity markets are demanding higher environmental performance from farmers and cattle ranchers. Protected areas have been established in the pathway of expanding agricultural frontiers. Finally, emerging carbon market incentives for reductions in deforestation could support these trends.


Author(s):  
Christoph Schwörer ◽  
Erika Gobet ◽  
Jacqueline F. N. van Leeuwen ◽  
Sarah Bögli ◽  
Rachel Imboden ◽  
...  

AbstractObserving natural vegetation dynamics over the entire Holocene is difficult in Central Europe, due to pervasive and increasing human disturbance since the Neolithic. One strategy to minimize this limitation is to select a study site in an area that is marginal for agricultural activity. Here, we present a new sediment record from Lake Svityaz in northwestern Ukraine. We have reconstructed regional and local vegetation and fire dynamics since the Late Glacial using pollen, spores, macrofossils and charcoal. Boreal forest composed of Pinus sylvestris and Betula with continental Larix decidua and Pinus cembra established in the region around 13,450 cal bp, replacing an open, steppic landscape. The first temperate tree to expand was Ulmus at 11,800 cal bp, followed by Quercus, Fraxinus excelsior, Tilia and Corylus ca. 1,000 years later. Fire activity was highest during the Early Holocene, when summer solar insolation reached its maximum. Carpinus betulus and Fagus sylvatica established at ca. 6,000 cal bp, coinciding with the first indicators of agricultural activity in the region and a transient climatic shift to cooler and moister conditions. Human impact on the vegetation remained initially very low, only increasing during the Bronze Age, at ca. 3,400 cal bp. Large-scale forest openings and the establishment of the present-day cultural landscape occurred only during the past 500 years. The persistence of highly diverse mixed forest under absent or low anthropogenic disturbance until the Early Middle Ages corroborates the role of human impact in the impoverishment of temperate forests elsewhere in Central Europe. The preservation or reestablishment of such diverse forests may mitigate future climate change impacts, specifically by lowering fire risk under warmer and drier conditions.


1990 ◽  
Vol 20 (10) ◽  
pp. 1559-1569 ◽  
Author(s):  
Christopher H. Baisan ◽  
Thomas W. Swetnam

Modern fire records and fire-scarred remnant material collected from logs, snags, and stumps were used to reconstruct and analyze fire history in the mixed-conifer and pine forest above 2300 m within the Rincon Mountain Wilderness of Saguaro National Monument, Arizona, United States. Cross-dating of the remnant material allowed dating of fire events to the calendar year. Estimates of seasonal occurrence were compiled for larger fires. It was determined that the fire regime was dominated by large scale (> 200 ha), early-season (May–July) surface fires. The mean fire interval over the Mica Mountain study area for the period 1657–1893 was 6.1 years with a range of 1–13 years for larger fires. The mean fire interval for the mixed-conifer forest type (1748–1886) was 9.9 years with a range of 3–19 years. Thirty-five major fire years between 1700 and 1900 were compared with a tree-ring reconstruction of the Palmer drought severity index (PDSI). Mean July PDSI for 2 years prior to fires was higher (wetter) than average, while mean fire year PDSI was near average. This 490-year record of fire occurrence demonstrates the value of high-resolution (annual and seasonal) tree-ring analyses for documenting and interpreting temporal and spatial patterns of past fire regimes.


Author(s):  
Ting-Hsuan Wang ◽  
Cheng-Ching Huang ◽  
Jui-Hung Hung

Abstract Motivation Cross-sample comparisons or large-scale meta-analyses based on the next generation sequencing (NGS) involve replicable and universal data preprocessing, including removing adapter fragments in contaminated reads (i.e. adapter trimming). While modern adapter trimmers require users to provide candidate adapter sequences for each sample, which are sometimes unavailable or falsely documented in the repositories (such as GEO or SRA), large-scale meta-analyses are therefore jeopardized by suboptimal adapter trimming. Results Here we introduce a set of fast and accurate adapter detection and trimming algorithms that entail no a priori adapter sequences. These algorithms were implemented in modern C++ with SIMD and multithreading to accelerate its speed. Our experiments and benchmarks show that the implementation (i.e. EARRINGS), without being given any hint of adapter sequences, can reach comparable accuracy and higher throughput than that of existing adapter trimmers. EARRINGS is particularly useful in meta-analyses of a large batch of datasets and can be incorporated in any sequence analysis pipelines in all scales. Availability and implementation EARRINGS is open-source software and is available at https://github.com/jhhung/EARRINGS. Supplementary information Supplementary data are available at Bioinformatics online.


2021 ◽  
Author(s):  
Florence Matutini ◽  
Jacques Baudry ◽  
Marie-Josée Fortin ◽  
Guillaume Pain ◽  
Joséphine Pithon

Abstract Context – Species distribution modelling is a common tool in conservation biology but two main criticisms remain: (1) the use of simplistic variables that do not account for species movements and/or connectivity and (2) poor consideration of multi-scale processes driving species distributions. Objectives – We aimed to determine if including multi-scale and fine-scale movement processes in SDM predictors would improve accuracy of SDM for low-mobility amphibian species over species-level analysis.Methods – We tested and compared different SDMs for nine amphibian species with four different sets of predictors: (1) simple distance-based predictors; (2) single-scale compositional predictors; (3) multi-scale compositional predictors with a priori selection of scale based on knowledge of species mobility and scale-of-effect (4) multi-scale compositional predictors calculated using a friction-based functional grain to account for resource accessibility with landscape resistance to movement.Results - Using friction-based functional grain predictors produced slight to moderate improvements of SDM performance at large scale. The multi-scale approach, with a priori scale selection led to ambiguous results depending on the species studied, in particular for generalist species.Conclusion - We underline the potential of using a friction-based functional grain to improve SDM predictions for species-level analysis.


2009 ◽  
Vol 3 (1-2) ◽  
pp. 21-38 ◽  
Author(s):  
Yuzuru Isoda ◽  
Akihiro Tsukamoto ◽  
Yoshihiro Kosaka ◽  
Takuya Okumura ◽  
Masakazu Sawai ◽  
...  

This paper explores a method for creating large-scale urban 3D models using Historical GIS data. The method is capable of automatically generating realistic VR models based on GIS data at a low cost. 3D models of houses are created from polygon data, fences from line data, and pedestrians and trees from point data. The method is applied to the Virtual Kyoto Project in which the landscape of the whole city of Kyoto of the early Edo era (ca 17C) is reconstructed.


Author(s):  
Athanasios Alexopoulos ◽  
Andreas Kanavos ◽  
Konstantinos Giotopoulos ◽  
Alaa Mohasseb ◽  
Mohamed Bader-El-Den ◽  
...  

Author(s):  
Rodion V. Savinov ◽  

The Article is devoted to the Representative of the Early Neo-Scholasticism, Span­ish Thinker Jaume Balmes. The Focus of Attention is the Interpretation of the Kan­tian Doctrine of Knowledge, which Balmes proposed in the Fourth Book of his “Filosofia Fundamental”(1846). It is shown that contrary to the generally negative attitude towards Kant and the Philosophy of Criticism that prevailed by the 1830s in Catholic Intellectual Culture, Balmes not only seriously studies and evaluates the Results of Kantian Criticism, but also he finds many points of contact between Criticism and Scholasticism, for which he undertakes a large-scale rewriting of the Kantian Theory of Knowledge in Terms of Scholasticism. At the same time, he of­fers Criticism of Kantian philosophy based on the Resources of the Scholastic Tra­dition, which allows integrating the Transcendental Analysis of Cognition devel­oped by Kant into the Methods of Scholastic Philosophy. Balmes sought to restore the Possibility of Metaphysical Knowledge, as a Result of which he excluded a number of Important Points of the Kantian Concept, he changed idea of a priori, setting the Boundaries of Sensuality and Reason, to a moving and dynamic “Agent Intellect” (entendimento agente), and Balmes replaced a transcendental subject by a “Universal Reason” (razón universal). In Conclusion, it is shown that Balmes’ Interpretation had a profound Influence on the Development of Understanding of Kantian Philosophy in Neo-Scholasticism and Neo-Thomism.


Author(s):  
Zahid Raza ◽  
Deo P. Vidyarthi

Computational Grid attributed with distributed load sharing has evolved as a platform to large scale problem solving. Grid is a collection of heterogeneous resources, offering services of varying natures, in which jobs are submitted to any of the participating nodes. Scheduling these jobs in such a complex and dynamic environment has many challenges. Reliability analysis of the grid gains paramount importance because grid involves a large number of resources which may fail anytime, making it unreliable. These failures result in wastage of both computational power and money on the scarce grid resources. It is normally desired that the job should be scheduled in an environment that ensures maximum reliability to the job execution. This work presents a reliability based scheduling model for the jobs on the computational grid. The model considers the failure rate of both the software and hardware grid constituents like application demanding execution, nodes executing the job, and the network links supporting data exchange between the nodes. Job allocation using the proposed scheme becomes trusted as it schedules the job based on a priori reliability computation.


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