Fire ecology is a branch of science that investigates the complex relationships between fire and ecosystems. Scientists and land managers gain insight into the ecological significance of fire through a thorough examination of fire regimes, behavior, impacts, adaptations, and management. This article investigates the role of fire in ecosystems, its effects on flora, fauna, soil, and water, as well as organisms’ adaptive mechanisms. It also emphasizes the significance of fire management in maintaining healthy and resilient ecosystems. According to fire statistics kept up to date by the BC Forest Service, 181,000 fires are believed to have destroyed 11,207,000 hectares between 1912 and 2004. Because so many significant fires in the early 1900s went undetected or unrecorded, this figure is understated. However, other areas—particularly in the grasslands and dry interior forests—burned more than once over the time of record.
WILDFIRES, THEIR ORIGIN & CHAOS
For millions of years, spontaneous combustion, volcanic eruptions, and lightning strikes have been the primary natural causes of wildfires on Earth. One of the most frequent all-natural sources of wildfires is lightning. Due to the heat produced when lightning strikes dry plants, a fire may start.
Because of their quick spread and destructive nature, wildfires have the potential to create tremendous havoc and destruction. They may have anthropogenic causes, such as unintentional ignition, arson, agricultural practices, equipment failure, and negligent behavior.
Wildfires can quickly consume enormous expanses of vegetation, such as forests, meadows, and shrublands, when they happen. They can lead to the destruction of homes, infrastructure, and natural habitats and represent a hazard to human lives, property, and wildlife. People are displaced by wildfires, evacuation efforts are made, transportation is disrupted, and local communities’ economies are affected.
AFTERMATH OF WILDFIRES
The air quality in the surrounding areas might suffer significantly as a result of wildfires. Wildfires can worsen the air quality and raise the levels of air pollution by releasing smoke, particulate matter, and other pollutants.PM2.5, also referred to as fine particulate matter, is widely dispersed into the air by wildfires. These tiny particles have a negative impact on health since they can easily travel deep into the respiratory system. Poor air quality can be indicated by elevated AQI measurements caused by high levels of PM2.5.Regional air quality can be impacted by large-scale wildfires. For instance, large-scale wildfires in one place might produce pollutants that are transported by prevailing winds to far areas. This may cause the AQI to rise in areas far from the actual fire site.
FIRE REGIMES & BEHAVIOUR
Fire Regimes: The patterns and properties of fire in a specific ecosystem are referred to as fire regimes. They include fire frequency, intensity, season, and size. Fire regimes vary amongst ecosystems and are regulated by factors such as climate, vegetation type, topography, and human activity.
Fire Behavior: The behavior of a fire defines how it spreads and interacts with its surroundings. Fuel availability, environmental conditions (temperature, humidity, wind), and geography all play important roles in shaping fire behavior. Understanding fire behavior aids in the prediction of fire spread and intensity.
Although the “coevolution” of plant species and fire regimes is increasingly understood to be a major driver of many ecological processes (Archibald et al., 2018), it is still unknown how much these co-evolutionary connections have affected specific landscapes and biomes.
Effects of Fire on Ecosystems:
Fire has both direct and indirect effects on ecosystems. Direct consequences include vegetation combustion, which causes changes in plant composition and structure. Changes in nutrient cycling, soil characteristics, and wildlife habitat are examples of indirect effects. Some ecosystems have evolved to rely on fire for ecological processes such as seed germination and nutrient recycling. Uncontrolled fires, on the other hand, can result in the loss of flora, biodiversity, and the degradation of soil and water quality.
Although only 28.5% of the impacts of fires on Ecosystem Services (ES) were reported to be beneficial, overall our research indicates that negative effects (46.6%) predominate. In a recent study of ES in Colorado montane habitats, negative effects were likewise predominate (>50%) (Vukomanovic and Steelman 2019). However, it is important to keep in mind that managers and researchers have been studying the damaging effects of fire on the environment for decades (e.g., DeBano and Conrad 1978; Hauer and Spencer 1998), and that, according to Doerr and Santn (2016), fire is primarily regarded by society as a significant environmental and socioeconomic hazard.
Fire Management and Conservation:
To achieve specific goals including lowering fuel loads, regaining ecosystem health, and controlling wildfire hazards, fire management entails the planned and regulated use of fire. Prescribed burning is one technique that can simulate natural fire regimes, reducing the risk of uncontrolled fires and enhancing ecosystem resilience. However, efforts to put out fires must be tempered with an understanding of the significance of fire in the environment. Ecological restoration and conservation initiatives frequently use fire management techniques to preserve ecosystems that can withstand fire, safeguard biodiversity, and reduce the threats posed by uncontrolled fires.
Animals and plant species have developed a variety of adaptations to endure, withstand fire, or even profit from it. Trees may survive powerful fires because of their thick bark, which shields the cambium layer. Some plants produce seeds that are latent until they germinate in response to fire. Certain animal traits or physiological characteristics let them avoid or tolerate fire. These adaptations are a result of the long-standing connection between fire and the evolution of ecosystems.
According to Keeley, Pausas, Rundel, Bond, and Bradstock (2011), fire-adaptive traits include such traits that are vital to, post-fire recruitment (serotiny i.e. Late in development; fire-stimulated germination), resprouting: Resprouters are plant species that can survive fire by regenerating new growth from dormant vegetative buds, and, either fire resistance (thick bark) or fire promotion (resin content and branch retention).
2019 Wildfires in the Amazon Rainforest:
The Amazon rainforest, referred to as the “lungs of the Earth,” saw a sharp rise in wildfires in 2019. The fires, which were frequently started on purpose for agricultural and land clearance objectives, emitted a great deal of smoke and particulate matter. Long-distance smoke migration caused air quality to degrade and AQI levels to rise in nearby Brazilian cities like So Paulo as well as neighboring Bolivia and Peru. Nearly three million residents of 90 municipalities in the Amazon region were exposed to dangerous levels of fine particulate matter, or PM 2.5, that were higher than the limit the World Health Organisation (WHO) recommends for health protection.In 168 municipalities, the number grew to 4.5 million in September. IEPS, in collaboration with IPAM and Human Rights Watch, undertook a statistical analysis that revealed 2,195 hospitalisations for respiratory illnesses linked to the fires. Of them, 1,080 (49%) were seniors 60 years of age or older, while 467 (21%) involved infants aged 0 to 12 months. According to the study, individuals who were exposed to air pollution from fires in 2019 required hospitalization for a total of 6,698 days.
2021 Simlipal forest fires:
Due to a below-average monsoon the year before, the Simlipal Biosphere Reserve endured a protracted dry season in 2021 that was accompanied by numerous fires.More than 3400 small-scale fires have been registered by authorities in the biosphere reserve since early February, 350 of which have taken place inside the tiger reserve. The Odisha state government declared a response on March 4, 2021, after the fires had been blazing for more than ten days. More than 1000 people, including fire and forest guards, as well as 40 fire tenders and blower machines, were sent to contain the fire. For the purpose of conducting forest patrols, Simlipal is divided into 21 “ranges,” and at this point, the fire had touched 8 of these ranges. Officials from the Forest Department claimed that extremely high temperatures made the situation worse.
2023 Canadian Wildfires:
Canada has been experiencing an ongoing, record-breaking string of wildfires since March 2023, with the intensity increasing beginning in June. The 2023 wildfire season was deemed to be worse than the 1989, 1995, and 2014 fire seasons on June 25 by the Canadian Interagency Forest Fire Centre.
599 of the 907 active wildfires were assessed to be “out of control” as of July 17, and 4,193 fires had scorched 10,193,171 hectares (25,187,874 acres) as of that date. The effects of the fires have been lessened thanks to international aid. Air quality alerts and evacuations have been brought on by smoke from the wildfires in Canada and the US. The Minnesota Pollution Control Agency issued a number of alerts in May owing to the poor air quality brought on by smoke from fires in Alberta and Saskatchewan. By May 21, 2023, air quality alerts were issued in Colorado, Montana, Nebraska, North Dakota, South Dakota, Utah, Wisconsin, and Washington due to smoke from the Alberta wildfires.Washington, D.C., Maryland, Pennsylvania, and Virginia experienced poor air quality on June 2 as a result of smoke from the wildfires in Nova Scotia.Washington, D.C., Maryland, Pennsylvania, and Virginia experienced poor air quality on June 2 as a result of smoke from the wildfires in Nova Scotia.
Fire ecology provides crucial insights into the complex relationship between fire and ecosystems. Understanding fire regimes, behavior, and impacts aids in developing fire management strategies that strike a balance between the requirement for ecosystem preservation and restoration. We can better understand the ecological importance of fire and work towards a coexisting with fire that is sustainable if we take into account its role in sustaining robust and healthy ecosystems.
– Abhiraj Parihar (Haritima Volunteer)