Fall and spring grazing influence fire ignitability and initial spread in shrub steppe communities

2017 ◽  
Vol 26 (6) ◽  
pp. 485 ◽  
Author(s):  
Kirk W. Davies ◽  
Amanda Gearhart ◽  
Chad S. Boyd ◽  
Jon D. Bates

The interaction between grazing and fire influences ecosystems around the world. However, little is known about the influence of grazing on fire, in particular ignition and initial spread and how it varies by grazing management differences. We investigated effects of fall (autumn) grazing, spring grazing and not grazing on fuel characteristics, fire ignition and initial spread during the wildfire season (July and August) at five shrub steppe sites in Oregon, USA. Both grazing treatments decreased fine fuel biomass, cover and height, and increased fuel moisture, and thereby decreased ignition and initial spread compared with the ungrazed treatment. However, effects differed between fall and spring grazing. The probability of initial spread was 6-fold greater in the fall-grazed compared with the spring-grazed treatment in August. This suggests that spring grazing may have a greater effect on fires than fall grazing, likely because fall grazing does not influence the current year’s plant growth. Results of this study also highlight that the grazing–fire interaction will vary by grazing management. Grazing either the fall or spring before the wildfire season reduces the probability of fire propagation and, thus, grazing is a potential fuel management tool.


2004 ◽  
Vol 34 (11) ◽  
pp. 2284-2293 ◽  
Author(s):  
Emilio Chuvieco ◽  
Inmaculada Aguado ◽  
Alexandros P Dimitrakopoulos

Fuel moisture content (FMC) estimation is a critical part of any fire danger rating system, since fuel water status is determinant in fire ignition and fire propagation. However, FMC alone does not provide a comprehensive assessment of fire danger, since other factors related to fire ignition (lightning, human factors) or propagation (wind, slope) also need to be taken into account. The problem in integrating all these factors is finding a common scale of danger rating that will make it possible to derive synthetic indices. This paper reviews the importance of FMC in fire ignition and fire propagation, as well as the most common methods of estimating FMC values. A simple method to convert FMC values to danger ratings is proposed, based on computing ignition potential from thresholds of moisture of extinction adapted to each fuel. The method has been tested for the Madrid region (central Spain), where a fire danger assessment system has been built. All the variables related to fire danger were integrated into a dedicated geographic information system and information provided to fire managers through a web mapping server.



2021 ◽  
Vol 7 (167) ◽  
pp. 46-50
Author(s):  
S. Burlutska ◽  
O. Chabanenko

The world has not yet come up with a single recipe for fighting corruption. But thanks to constant progress, anti-corruption strategies are replenished with effective innovation mechanisms. The global experience of using blockchain opens up new prospects for eliminating corruption in the world. Blockchain is an opportunity not only to modernize outdated functional systems, but also to apply new, more effective means of combating corruption and cybercrime. One of the main advantages of the blockchain is that all network participants have a register of transaction data. Therefore, if someone decides to hide, delete or change their recalculations in the accounting book, then copies of these transactions still remain in tens of thousands of other users and the system immediately accesses them. Therefore, a few minutes will be enough to solve the issues of detecting a crime. Today, it is worth highlighting 3 types of widespread use of blockchain technology in the fight against corruption: identity verification, asset registration and tracking of monetary transactions. For example, you can check the purpose of money transfers in real time, see salary payments, and compare prices among suppliers. Like any type of crime, corruption in human society cannot be completely excluded. However, decentralized platforms functioning on blockchain technology, already today, firstly, can directly bring together the customer and the executor, and secondly, all the conditions agreed upon by the participants can then be easily verified (thus, it will be impossible to imperceptibly inflate the price when using blockchain). Blockchain technology is in demand because it creates an unprecedented degree of trust in information in relationships between individuals and public organizations, or between the state, people and private institutions.



Author(s):  
Austin Tonderai Nyakurerwa

The chapter focused on the institutional repository as a knowledge management tool that enhances the visibility of libraries in the 21st century. The researcher mainly relied on content analysis to gather research data. The researcher took a swipe on the uptake of institutional repositories the world over and an analysis of how an institutional repository could be used as a knowledge management tool was done. The researcher also conducted a situational analysis of the MSU institutional repository and assessed the impact of the digital repository on the visibility of the library. The author used the Webometrics Ranking of Universities in Zimbabwe to assess how universities are ranked in Zimbabwe.





2013 ◽  
Vol 22 (3) ◽  
pp. 353 ◽  
Author(s):  
Kirk W. Davies ◽  
Aleta M. Nafus

Many exotic annual grasses are believed to increase wildfire frequency to the detriment of native vegetation by increasing fine fuels and thus, creating a grass-fire cycle. However, information on differences in fuel characteristics between invaded and non-invaded plant communities is lacking, or is based mainly on speculation and anecdotal evidence. We compared fuel biomass, cover, continuity and moisture content in plant communities invaded and not invaded by cheatgrass (Bromus tectorum L.), an exotic annual grass, in 2010 and 2011 in south-eastern Oregon, USA. Annual grass-invaded communities had higher fine fuel amounts, greater fuel continuity, smaller fuel gaps and lower fuel moisture content than did non-invaded plant communities. These conditions would increase the probability that ignition sources would contact combustible fuels and that fires would propagate. Fuel characteristics in the annual grass-invaded communities in our study may also support faster spreading fires. Fuel moisture content was low enough to burn readily more than a month earlier in annual grass-invaded communities than in non-invaded communities, thereby expanding the wildfire season. The cumulative effect of these differences in fuel characteristics between exotic annual grass-invaded and non-invaded plant communities is an increased potential for frequent, large-scale, fast-spreading wildfires. We suggest that research is needed to develop methods to mediate and reverse these changes in fuel characteristics associated with B. tectorum invasion.



2013 ◽  
Vol 62 (5) ◽  
pp. 647-665 ◽  
Author(s):  
Hebe Vessuri ◽  
Jean-Claude Guédon ◽  
Ana María Cetto

The current competition regime that characterizes international science is often presented as a quest for excellence. It diversely affects research in Latin America and research in the Organization for Economic Co-operation and Development (OECD) countries. This article asks how this competition regime may orient the direction of research in Latin America, and to whose advantage. It is argued that, by relating excellence to quality differently, a research policy that seeks to improve the level of science in Latin America while preserving the possibility of solving problems relevant to the region can be designed. Competition, it is also argued, certainly has its place in science, but not as a general management tool, especially if the goal is to improve overall quality of science in Latin America. Scientific competition is largely managed through journals and their reputation. Therefore, designing a science policy for Latin America (and for any ‘peripheral’ region of the world) requires paying special attention to the mechanisms underpinning the production, circulation and consumption of scientific journals. So-called ‘international’ or ‘core’ journals are of particular interest as local, national, or even regional journals must struggle to find their place in this peculiar publishing eco-system.



2014 ◽  
Vol 7 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Phil S. Allen ◽  
Susan E. Meyer

AbstractEcological restoration of shrub–steppe communities in the western United States is often hampered by invasion of exotic annual grasses during the process. An important question is how to create restored communities that can better resist reinvasion by these weeds. One hypothesis is that communities comprised of species that are functionally similar to the invader will best resist invasion, while an alternative hypothesis is that structurally more complex and diverse communities will result in more effective competitive exclusion. In this field experiment, we examined the effects of restored community structure on the invasion success of three annual grass weeds (downy brome, jointed goatgrass, and cereal rye). We created replicated community plots that varied in species composition, structural complexity and density, then seeded in annual grass weeds and measured their biomass and seed production the following year, and their cover after 1 and 3 yr. Annual grass weeds were not strongly suppressed by any of the restored communities, indicating that it was difficult for native species to completely capture available resources and exclude annual grass weeds in the first years after planting. Perennial grass monocultures, particularly of the early seral grass bottlebrush squirreltail, were the most highly invaded communities, while structurally complex and diverse mixtures of shrubs (big sagebrush, rubber rabbitbrush), perennial grasses (bluebunch wheatgrass and bottlebrush squirreltail) and forbs (Lewis flax, Utah sweetvetch, hairy golden aster, gooseberryleaf globemallow) were more resistant to invasion. These results suggest that restoration of sagebrush steppe communities resistant to annual grass invasion benefits from higher species diversity; significant reduction of weed propagule pressure prior to restoration may be required.



Author(s):  
F. V. Kozak ◽  
T. V. Dikun ◽  
L. I. Gaeva ◽  
Y. M. Demyanchuk

Natural gas (methane) is widely used in the world as an alternative to the use ofliquid petroleum fuels. This makes it possible to reduce the harmfulness of emissions into theatmosphere, cheapen the use of motor vehicles, and extend the life of engines. This is especiallytrue for Ukraine with its powerful network of AGNKS. However, natural gas, despite itssignificant reserves, is an exhaustive resource, like oil. And so its value is constantly increasing.An alternative is to use biogas - a product of recycling biowaste of various origins. However, thecomposition of biogas is significantly different from natural gas. For its use, additional cleaningis required from the ballast components or, alternatively, as a fuel, a mixture of biogas andnatural gas.The prospects of using biogas in the composition of the mixture with natural gas, changesin fuel characteristics and their estimated value depending on the percentage content of thecomponents are analyzed.



PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2649 ◽  
Author(s):  
G. Matt Davies ◽  
Colin J. Legg

Fire is widely used as a traditional habitat management tool in Scotland, but wildfires pose a significant and growing threat. The financial costs of fighting wildfires are significant and severe wildfires can have substantial environmental impacts. Due to the intermittent occurrence of severe fire seasons, Scotland, and the UK as a whole, remain somewhat unprepared. Scotland currently lacks any form of Fire Danger Rating system that could inform managers and the Fire and Rescue Services (FRS) of periods when there is a risk of increased of fire activity. We aimed evaluate the potential to use outputs from the Canadian Fire Weather Index system (FWI system) to forecast periods of increased fire risk and the potential for ignitions to turn into large wildfires. We collated four and a half years of wildfire data from the Scottish FRS and examined patterns in wildfire occurrence within different regions, seasons, between urban and rural locations and according to FWI system outputs. We used a variety of techniques, including Mahalanobis distances, percentile analysis and Thiel-Sen regression, to scope the best performing FWI system codes and indices. Logistic regression showed significant differences in fire activity between regions, seasons and between urban and rural locations. The Fine Fuel Moisture Code and the Initial Spread Index did a tolerable job of modelling the probability of fire occurrence but further research on fuel moisture dynamics may provide substantial improvements. Overall our results suggest it would be prudent to ready resources and avoid managed burning when FFMC > 75 and/or ISI > 2.



Fire ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 26
Author(s):  
Andrea Trucchia ◽  
Mirko D’Andrea ◽  
Francesco Baghino ◽  
Paolo Fiorucci ◽  
Luca Ferraris ◽  
...  

PROPAGATOR is a stochastic cellular automaton model for forest fire spread simulation, conceived as a rapid method for fire risk assessment. The model uses high-resolution information such as topography and vegetation cover considering different types of vegetation. Input parameters are wind speed and direction and the ignition point. Dead fine fuel moisture content and firebreaks—fire fighting strategies can also be considered. The fire spread probability depends on vegetation type, slope, wind direction and speed, and fuel moisture content. The fire-propagation speed is determined through the adoption of a Rate of Spread model. PROPAGATOR simulates independent realizations of one stochastic fire propagation process, and at each time-step gives as output a map representing the probability of each cell of the domain to be affected by the fire. These probabilities are obtained computing the relative frequency of ignition of each cell. The model capabilities are assessed by reproducing a set of past Mediterranean fires occurred in different countries (Italy and Spain), using when available the real fire fighting patterns. PROPAGATOR simulated such scenarios with affordable computational resources and with short CPU-times. The outputs show a good agreement with the real burned areas, demonstrating that the PROPAGATOR can be useful for supporting decisions in Civil Protection and fire management activities.



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