Proforestation is the practice of protecting existing natural forests to foster continuous growth, carbon accumulation, and structural complexity. [2] [3] It is recognized as an important forest based strategy for addressing the global crises in climate and biodiversity. [3] [4] Forest restoration can be a strategy for climate change mitigation. [5] : 37 Proforestation complements other forest-based solutions like afforestation, reforestation and improved forest management.
Allowing proforestation in some secondary forests will increase their accumulated carbon and biodiversity over time. Strategies for proforestation include rewilding, [6] such as reintroducing apex predators and keystone species as, for example, predators keep the population of herbivores in check (which reduce the biomass of vegetation). Another strategy is establishing wildlife corridors connecting isolated protected areas. [7] [8]
Proforestation refers specifically to enabling continuous forest growth uninterrupted by active management or timber harvesting, a term coined by scientists William Moomaw, Susan Masino, and Edward Faison. [9] [2]
Proforestation is a natural climate solution that addresses climate mitigation and adaptation by prioritizing natural processes and regeneration in existing forests to optimize cumulative carbon and ecological complexity. [2]
Proforestation seeks to strengthen and sustain complexity and carbon accumulation in forest ecosystems. As ecologist Ed Faison states, "forests provide these services incredibly well when left alone; in fact over time unmanipulated forests develop the greatest complexity and accumulated carbon storage and therefore serve as models for "ecological forestry" techniques. [10] [11] [12]
Proforestation differs from agroforestry or the cultivation of forest plantations, the latter consisting of similarly aged trees of just one or two species. Plantations can be an efficient source of wood but often come at the expense of natural forests and cultivate little habitat for biodiversity, such as dead and fallen trees or understory plants. Further, once factoring in emissions from clearing the land and the decay of plantation waste and products at the end of their often brief lifecycles (e.g. paper products), plantations sequester 40 times less carbon than natural forests. [13]
Proforestation is specifically recommended in “World Scientists’ Warning of a Climate Emergency, as a means to “quickly curtail habitat and biodiversity loss” and protect “high carbon stores” and areas “with the capacity to rapidly sequester carbon.” [14]
Proforestation is part of a suite of forest-based climate solutions that includes avoided conversion, afforestation, reforestation and improved forest management. [15]
Proforestation offers many benefits, from sequestering carbon for climate change mitigation and sustaining biodiversity, to providing ecosystem services, including water filtration, flood buffering, and maintaining soil health. [16]
According to the Intergovernmental Panel on Climate Change, about 730 billion tons of CO2 (or 199 billion tons of carbon) will need to be removed from the atmosphere by 2100. This is an enormous amount (more than was emitted by the US, the UK, Germany and China since the Industrial Revolution) and forests will play an essential role in this removal. [13]
In the United States, forests currently remove enough atmospheric CO2 to reduce national net emissions by 11 percent each year. [2] And each additional 8.6 million hectares of land regenerated to natural forest would sequester another 1 billion tons of carbon by 2100. [13]
Research has found that in complex forests of all types, the largest one percent of trees (by diameter) store about half of the carbon. [9] Facilitating growth of larger trees will increase carbon sequestration. Research also found that replacing old growth forests with young forests, even counting carbon ‘sequestered’ in long-lasting wood products (e.g. houses), leads to an overall increase in carbon emissions and that proforestation leads to the largest carbon storage capability. [17] [18] Compared to clearcutting, complex forest ecosystems retain more than twice the carbon. [19]
Wilderness areas are examples of proforestation and have been shown to reduce the rate of extinction at broad scales. [20] Primary forests in some regions have been shown to hold far more biodiversity than “disturbed forests.” According to a meta-analysis of 138 studies of tropical forest ecosystems, researchers found that “most forms of forest degradation have an overwhelmingly detrimental effect on tropical biodiversity,” leading them to conclude that “when it comes to maintaining tropical biodiversity, there is no substitute for primary forests.” [21] Proforestation also results in greater cumulative carbon storage and structural complexity compared to that found in similar forests that are actively managed. [10] Enhanced structural complexity is achieved via dynamic natural processes and disturbances which often give rise to a greater abundance and diversity of flora and fauna. [10] [22] [23] Proforestation is therefore a powerful forest-based strategy that can help address the global crises in climate and biodiversity. [24]
Forests provide a variety of ecosystem services: cleaning the air, accumulating carbon, filtering water, and reducing flooding and erosion. [25] Forests are the most biodiverse land-based ecosystem, and provide habitat for a vast array of animals, birds, plants and other life. They can provide food and material and also opportunities for recreation and education. Research has found that forest plantations “may result in reduced diversity and abundance of pollinators compared with natural forests that have greater structural and plant species diversity.” [26]
1.6 billion people worldwide depend on forests for their livelihoods, including 300-350 million (half of whom are Indigenous peoples) who live near or within “dense forests” and depend almost entirely on these ecosystems for their survival. [27] Rural households in Asia, Africa, and Latin America also depend on forests for about a quarter of their total incomes, with about half of this in the form of food, fodder, energy, building materials and medicine. [28] Proforestation can protect full native biodiversity and support the forests and other land types that provide resources we need. For example, research has found that old growth and complex forests are more resistant to the effects of climate change. One study found that taller trees had increased drought resistance, being able to capture and retain water better, due to their deeper root system and larger biomass. This means that even in dry conditions, these trees continued to photosynthesize at a higher rate than smaller trees. [29] Further, old-growth forests have been shown to be more resistant to fires compared to young forests with trees that have thinner bark and with more fuel available for increasing temperatures and fire damage. [30] Proforestation can help to reduce fire risks to forests and the surrounding communities. They can also help absorb water and prevent flooding to surrounding communities. [31] Considering the variety of ecosystem services complex forests provide, sustaining healthy forests means adjacent communities will be better off as well.
Considering the rise in the acreage of forests that have experienced wildfires in the United States during the last three decades. [32] It is essential to consider the connection between forest management practices and forest fires. Many believe that the intensity and scale of recent fires are closely linked to the accumulation of fuels in the forest understory. This accumulation occurs due to a lack of forest management efforts aimed at reducing these fuels, which typically include activities like pulping, masticating, thinning, raking, and prescribed burning. Nonetheless, there is evidence to suggest that proforestation may, in fact, decrease the risk of wildfires. [33] Several key factors warrant consideration in this regard. Firstly, it's important to acknowledge that fire is a natural and intrinsic component of forest ecosystems in the Western U.S. Secondly, the occurrence, size, and extent of wildfires are typically not entirely preventable, even with efforts focused on removing fuels from the forest. [33] Thirdly, it's worth noting that the current extent of forest area burned by wildfires is considerably lower than it was during the first half of the twentieth century, a period characterized by more intensive timber harvesting practices and less active wildfire suppression efforts. [34] Interestingly, over the past three decades, intact forests in the Western U.S. experienced significantly lower-intensity wildfires compared to managed forests. [35] The heightened potential for fuel in intact forests seems to be balanced out by factors such as drier conditions, higher wind speeds, the presence of smaller trees, and the presence of residual, more combustible fuels found in managed areas. [33] Instead of combating wildfires indiscriminately, the most effective strategy involves restricting development in fire-prone regions, establishing and defending zones around existing developments, particularly in wildland-urban interface areas, and implementing construction codes that prioritize fire-resistant structures. [33]
Proforestation was featured in July 2019 on NEXT [36] by the New England News Collaborative on New England Public Radio [37] and on the EnviroShow. [38] It has also been highlighted in major editorials, [39] in a letter signed by 370 top scientists with expertise in climate, ecology and health, and recommended specifically in “World Scientists’ Warning of a Climate Emergency, as a means to “quickly curtail habitat and biodiversity loss” and protect “high carbon stores” and areas “with the capacity to rapidly sequester carbon.” [40]
Leveraging nature-based solutions is consistent with the recommendations of the Paris Agreement and the Intergovernmental Panel on Climate Change (IPCC) and the goals of the US Climate Alliance. Nature-based solutions can counteract the negative climate, environmental and ecological effects of deforestation and forest manipulation and extraction. [38] [41]
In August 2019, an IPCC Special Report titled “Climate Change and Land” identified land use as a major driver of and a major solution to the climate crisis. A piece in The Conversation referred to the IPCC Special Report and highlighted the importance of natural forests and proforestation. Climate activist Bill McKibben came out against biomass and in favor of proforestation in an article titled "Don’t Burn Trees to Fight Climate Change—Let Them Grow" in the New Yorker. This policy position was echoed in a blog [42] piece co-released by the Nicholas School at Duke University Duke and the Cary Institute for Ecosystem Studies.
Proforestation was also prominently featured at the Climate Action Network International. Recent press releases on proforestation include Trinity College, Frontiers, and Symposium at Harvard Forest.
Reforestation is the practice of restoring previously existing forests and woodlands that have been destroyed or damaged. The prior forest destruction might have happened through deforestation, clearcutting or wildfires. Two important purposes of reforestation programs are for harvesting of wood or for climate change mitigation purposes. Reforestation can also help with ecosystem restoration. One method for reforestation is to establish tree plantations, also called plantation forests. They cover about 131 million ha worldwide, which is 3 percent of the global forest area and 45 percent of the total area of planted forests.
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on Earth and dominate the landscape worldwide. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands. They cover 31–69% of the Earth's land area.
A controlled or prescribed (Rx) burn is the practice of intentionally setting a fire to change the assemblage of vegetation and decaying material in a landscape. The purpose could be for forest management, ecological restoration, land clearing or wildfire fuel management. A controlled burn may also refer to the intentional burning of slash and fuels through burn piles. Controlled burns may also be referred to as hazard reduction burning, backfire, swailing or a burn-off. In industrialized countries, controlled burning regulations and permits are usually overseen by fire control authorities.
Forestation is a vital ecological process where forests are established and grown through afforestation and reforestation efforts. Afforestation involves planting trees on previously non-forested lands, while reforestation focuses on replanting trees in areas that were once deforested. This process plays an important role in restoring degraded forests, enhancing ecosystems, promoting carbon sequestration, and biodiversity conservation.
Coarse woody debris (CWD) or coarse woody habitat (CWH) refers to fallen dead trees and the remains of large branches on the ground in forests and in rivers or wetlands. A dead standing tree – known as a snag – provides many of the same functions as coarse woody debris. The minimum size required for woody debris to be defined as "coarse" varies by author, ranging from 2.5–20 cm (1–8 in) in diameter.
An old-growth forest is a forest that has developed over a long period of time without disturbance. Due to this, old-growth forests exhibit unique ecological features. The Food and Agriculture Organization of the United Nations defines primary forests as naturally regenerated forests of native tree species where there are no clearly visible indications of human activity and the ecological processes are not significantly disturbed. One-third of the world's forests are primary forests. Old-growth features include diverse tree-related structures that provide diverse wildlife habitats that increases the biodiversity of the forested ecosystem. Virgin or first-growth forests are old-growth forests that have never been logged. The concept of diverse tree structure includes multi-layered canopies and canopy gaps, greatly varying tree heights and diameters, and diverse tree species and classes and sizes of woody debris.
Fire ecology is a scientific discipline concerned with the effects of fire on natural ecosystems. Many ecosystems, particularly prairie, savanna, chaparral and coniferous forests, have evolved with fire as an essential contributor to habitat vitality and renewal. Many plant species in fire-affected environments use fire to germinate, establish, or to reproduce. Wildfire suppression not only endangers these species, but also the animals that depend upon them.
Afforestation is the establishment of a forest or stand of trees (forestation) in an area where there was no recent tree cover. In comparison, reforestation means re-establishing forest that have either been cut down or lost due to natural causes, such as fire, storm, etc. There are three types of afforestation: Natural regeneration, agroforestry and commercial plantations. The intended benefits of afforestation are numerous. In the context of climate change, afforestation can be helpful for climate change mitigation through the route of carbon sequestration. Afforestation can also improve the local climate through increased rainfall and by being a barrier against high winds. The additional trees can also prevent or reduce topsoil erosion, floods and landslides. Finally, additional trees can be a habitat for wildlife, and provide employment and wood products.
In ecology, a disturbance is a temporary change in environmental conditions that causes a pronounced change in an ecosystem. Disturbances often act quickly and with great effect, to alter the physical structure or arrangement of biotic and abiotic elements. A disturbance can also occur over a long period of time and can impact the biodiversity within an ecosystem.
Carbon sequestration is the process of storing carbon in a carbon pool. It plays a crucial role in mitigating climate change by reducing the amount of carbon dioxide in the atmosphere. There are two main types of carbon sequestration: biologic and geologic. Biologic carbon sequestration is a naturally occurring process as part of the carbon cycle. Humans can enhance it through deliberate actions and use of technology. Carbon dioxide is naturally captured from the atmosphere through biological, chemical, and physical processes. These processes can be accelerated for example through changes in land use and agricultural practices, called carbon farming. Artificial processes have also been devised to produce similar effects. This approach is called carbon capture and storage. It involves using technology to capture and sequester (store) CO
2 that is produced from human activities underground or under the sea bed.
The Lower Guinean forests also known as the Lower Guinean-Congolian forests, are a region of coastal tropical moist broadleaf forest in West Africa, extending along the eastern coast of the Gulf of Guinea from eastern Benin through Nigeria and Cameroon.
Deforestation in Nigeria refers to the extensive and rapid clearing of forests within the borders of Nigeria. This environmental issue has significant impacts on both local and global scales.
Forest restoration is defined as “actions to re-instate ecological processes, which accelerate recovery of forest structure, ecological functioning and biodiversity levels towards those typical of climax forest” i.e. the end-stage of natural forest succession. Climax forests are relatively stable ecosystems that have developed the maximum biomass, structural complexity and species diversity that are possible within the limits imposed by climate and soil and without continued disturbance from humans. Climax forest is therefore the target ecosystem, which defines the ultimate aim of forest restoration. Since climate is a major factor that determines climax forest composition, global climate change may result in changing restoration aims. Additionally, the potential impacts of climate change on restoration goals must be taken into account, as changes in temperature and precipitation patterns may alter the composition and distribution of climax forests.
A peatland is a type of wetland whose soils consist of organic matter from decaying plants, forming layers of peat. Peatlands arise because of incomplete decomposition of organic matter, usually litter from vegetation, due to water-logging and subsequent anoxia. Like coral reefs, peatlands are unusual landforms that derive mostly from biological rather than physical processes, and can take on characteristic shapes and surface patterning.
Deforestation is a primary contributor to climate change, and climate change affects the health of forests. Land use change, especially in the form of deforestation, is the second largest source of carbon dioxide emissions from human activities, after the burning of fossil fuels. Greenhouse gases are emitted from deforestation during the burning of forest biomass and decomposition of remaining plant material and soil carbon. Global models and national greenhouse gas inventories give similar results for deforestation emissions. As of 2019, deforestation is responsible for about 11% of global greenhouse gas emissions. Carbon emissions from tropical deforestation are accelerating.
Complex early seral forests, or snag forests, are ecosystems that occupy potentially forested sites after a stand-replacement disturbance and before re-establishment of a closed forest canopy. They are generated by natural disturbances such as wildfire or insect outbreaks that reset ecological succession processes and follow a pathway that is influenced by biological legacies that were not removed during the initial disturbance. Complex early seral forests develop with rich biodiversity because the remaining biomass provides resources to many life forms and because of habitat heterogeneity provided by the disturbances that generated them. In this and other ways, complex early seral forests differ from simplified early successional forests created by logging. Complex early seral forest habitat is threatened from fire suppression, thinning, and post-fire or post-insect outbreak logging.
Woody plant encroachment is a natural phenomenon characterised by the increase in density of woody plants, bushes and shrubs, at the expense of the herbaceous layer, grasses and forbs. It predominantly occurs in grasslands, savannas and woodlands and can cause biome shifts from open grasslands and savannas to closed woodlands. The term bush encroachment refers to the expansion of native plants and not the spread of alien invasive species. It is thus defined by plant density, not species. Bush encroachment is often considered an ecological regime shift and can be a symptom of land degradation. The phenomenon is observed across different ecosystems and with different characteristics and intensities globally.
Terrestrial ecosystems found in the boreal regions of North America and Eurasia cover 17% of the Earth's land surface, and contain more than 30% of all carbon present in the terrestrial biome. In terms of carbon storage, the boreal region consists of three ecosystems: boreal forest, peatland, and tundra. Vast areas of the globe and are contributing greatly to atmospheric carbon release due to increased temperature and fire hazard. High northern latitudes will experience the most significant increase in warming on the planet as a result of increased atmospheric greenhouse gases thus placing in jeopardy the carbon sink in these areas. In addition to the release of carbon through the melting of permafrost, high intensity wildfires will become more common and thus contribute to the release of stored carbon. This means that the boreal forest and its fire regime is becoming an increasingly more significant factor in determining the global carbon budget.
Carbon farming is a set of agricultural methods that aim to store carbon in the soil, crop roots, wood and leaves. The technical term for this is carbon sequestration. The overall goal of carbon farming is to create a net loss of carbon from the atmosphere. This is done by increasing the rate at which carbon is sequestered into soil and plant material. One option is to increase the soil's organic matter content. This can also aid plant growth, improve soil water retention capacity and reduce fertilizer use. Sustainable forest management is another tool that is used in carbon farming. Carbon farming is one component of climate-smart agriculture. It is also one of the methods for carbon dioxide removal (CDR).
Beverly Law is an American forest scientist. She is professor emeritus at Oregon State University known for her research on forest ecosystems, especially with respect to carbon cycling, fire, and how human actions impact future climate.