Trouble in the Golden State: California Wildfires

 

By Ana Rodriguez, WellKind Forestry Intern

Ana Rodriguez was an intern for WellKind Forestry during our summer 2022 session, exploring wildfires and other environmental topics.


California, known for its agricultural land and warm beaches, has faced a devastating reality in the past decade as a result of the flames that ravage the land every year. On average, California has about 1,065 wildfires each year, which result in major losses of property, tax dollars, and in the worst cases, lives. 

In 2021, the state recorded 16kha (thousands of hectares) of land burned during that year’s fire season. However, it played no comparison to the amount of land burned in 2020, which was 1.6Mha (millions of hectares) throughout the state (Harris et al, 2020). The increasing mileage of land burned each year varies depending on the fires’ geographical locations, but there are no signs of a decrease as of now. Due to the expanding consequences of climate change and the severe drought that results from the annual fires, the state of California has become vulnerable when it comes to preserving its land from great distress. 

Wildfires are a natural system that prevail in California's environmental cycle. They can bring great developments for the soil as they allow healthy nutrients, which were once thought to be lost, to resurface onto the land (Jones, 2020). Fires cycle nutrients and allow natural areas to regenerate properly. For example, giant sequoias need fire to crack their seed cones and germinate. 

Nevertheless, the size and severity of wildfires have become much bigger and will continue to increase tremendously with time, creating ongoing problems for California’s environment. To illustrate, studies have shown how less tree regeneration occurred across all forest types in the 21st century following a wildfire (Stevens-Rumann et al, 2018). Among dry forest sites that burned prior to 2000, 68% had seedlings of any species present; this decreased significantly to 53% among dry forest sites that burned since 2000. The proportion of dry forest sites with seedling densities exceeding the criteria of the regeneration of trees was also lower after 21st-century wildfires, declining from 49% (in sites that burned prior to 2000) to 30% (in sites burned since 2000). Moist forest types exhibited a similar decline in regeneration, from 91 to 65%. This demonstrates the growing impacts wildfires can have on different ecosystems as the climate warms.

In regions with drier weather and more drought, fires are more likely to extend and are harder to put out once set in motion. The relationship between weather patterns and state of the soil in a certain area are factors that can predict the extent and severity of a wildfire (Park et al, 2021). Human activity when it comes to California wildfires broadens the range of severity each year as agricultural management and urban practices are prominent in the state. Meaning that the continuous use of flammable resources is more prominent in areas such as ranches and some suburban neighborhoods due to their drier landscapes which have been stripped away from helpful vegetation as a result of industrialization. 

A 2021 study on the effects of multiple land management practices and wildfires in California concluded that the general pattern shows that less intensive forest management decreases the total greenhouse emissions, while more active forest management (such as thinning trees) increases  emissions (Di Vittorio et al.) Practices meant to control fire severity on the land can potentially have detrimental effects.

Forest thinning, a form of land management of cutting trees in densely forested areas, is one example of a flawed technique in intensive forest management. The largest study to date on forest thinning tracked its impacts from data dating back 30 years and covering 9.4 million hectares. It found that forests that were thinned actually had larger, more intense fires than areas that were not thinned (Bradley, Hanson, and Dellasala, 2016).

Younger generations of trees, when suppressed under intensive forest thinning, respond with positive results within the ecosystem they are in as it allows them to rejuvenate with better and healthier nutrients. However, this is not the same for older generations of trees. In fact, it was shown that when thinning happened in older trees, they were not able to obtain good growth or develop healthy nutrients once again. Meaning that all of the CO2  that was once trapped in older trees is now released into the atmosphere, warming the planet even more with each area of elderly trees cut down (Zald et al, 2022). This makes it more prone for fires to happen in areas with thinner forests as they expose the forest floor’s fuels to greater sun exposure, drying out the soil and allowing greater wind currents to reach the open forest stands (Western Watersheds Project, 2014).

This is why forest harvest and fuel reduction activities need to be reconsidered in favor of less intensive forest management and the conservation of forests, in order to reduce overall landscape carbon emissions. Even intensive land management methods which have positive short-term effects could drastically change with the increasing percentage of carbon dioxide being emitted as a result of those same practices, leading to irreversible consequences in later decades. 

As a state, California will continue to face harsh wildfires in seasons to come. The way to slow down the density and size of these fires is to take on preventive measures prior to each fire season. This is includes limiting the amount of forest acres that are thinned and creating stricter rules and regulation on human-caused burns in regions where wildfires are prone to happen. We all want to live in a safe California for generations to come, which is why better regulations need to be set in motion that allow our state’s ecosystems to flourish.



References

Bradley, C. M, et al. (2016, October 26). Does increased forest protection correspond to higher fire severity in frequent-fire forests of the western United States? Ecosphere. https://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/ecs2.1492#:~:text=We%20found%20no%20evidence%20to,linear%20mixed-effects%20modeling%20approaches

Di Vittorio, A. V., Simmonds, M. B., & Nico, P. (2021). Quantifying the effects of multiple land management practices, land cover change, and wildfire on the California landscape carbon budget with an empirical model. PLOS ONE. https://doi.org/10.1371/journal.pone.0251346

Harris, N., Munroe, T., & Levin, K. (2020). 6 Graphics Explain the Climate Feedback Loop Fueling US Fires. Www.wri.org. https://www.wri.org/insights/6-graphics-explain-climate-feedback-loop-fueling-us-fires utm_source=twitter&utm_medium=worldresources&utm_campaign=socialmedia&utm_term=71c109da-3699-422f-b35b-df6dae1ecdbd

Jones, A. (2020). How Do California’s Megafires Impact Birds?. Audubon California. https://ca.audubon.org/news/how-do-californias-megafires-impact-birds

Park, I., Mann, M., Flint, L., Flint, A., & Moritz, M. (2021). Relationships of climate, human activity, and fire history to spatiotemporal variation in annual fire probability across California. PLOS ONE. https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0254723#sec008

Roon, D. A., Dunham, J. B., & Groom, J. D. (2021). Shade, light, and stream temperature responses to riparian thinning in second-growth redwood forests of northern California. PLOS ONE. https://doi.org/10.1371/journal.pone.0246822

‌Western Watersheds Project.Why Thinning Forests is Poor Wildfire Strategy - Western Watersheds Project. (2014). Western Watersheds Project. https://westernwatersheds.org/gw-poor-wildfire-strategy/

Westover, R. H. (2021, August 19). Thinning the Forest for the Trees. US Forest Service. https://www.fs.usda.gov/features/thinning-forest-trees

Zald, H. S. J., Callahan, C. C., Hurteau, M. D., Goodwin, M. J., & North, M. P. (2022). Tree growth responses to extreme drought after mechanical thinning and prescribed fire in a Sierra Nevada mixed-conifer forest, USA. Forest Ecology and Management. https://doi.org/10.1016/j.foreco.2022.120107

 
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