Reforestation: Pros, Cons And Effects On Planet

What Is Reforestation And Its Causes

Reforestation is the act of restoring trees in an area where their population has been reduced due to either natural causes or human intervention. Reforestation after a wildfire by intentionally planting new trees or encouraging the natural recovery of degraded forests are just some examples of reforestation.

The necessity for reforestation can unfortunately arise for a variety of reasons. We can classify them into two broad categories:

• Human intervention: tree cutting, mining, clearing land for agriculture and construction purposes.
• Natural disasters: droughts, wildfires, floods, storms, pest and disease infestations. The frequency of extreme weather events is on the rise as a result of climate change, which is driving up average temperatures and increasing the variability of precipitation.

Reforestation is especially important in areas subject to commercial logging. There are several purposes for reforestation on these lands:

• restoration after harvesting merchantable timber;
• compensation after the land expansion due to human activities;
• refreshing after forest aging;
• regeneration after natural calamities;
• maintaining ecosystem balance and biodiversity;
• providing habitats for eco-communities, etc.

The best reforestation practices recommend immediate planting once a forest is cut down or destroyed. Thus, tree-felling companies are to restore the balance by planting new trees after logging, according to governmental regulations in many countries.

The UN New York Declaration of 2014 obliged countries to reduce deforestation twice by 2020 and halt it by 2030 ^{What is the New York Declaration on Forests? Forest Declaration Platform.}. However, its annual rate almost doubled instead.

Benefits Of Reforestation

Ecosystems can better withstand future stresses from things like climate change and wildfires when they have been reforested. The most significant benefits that can be gained via reforestation are as follows.

Reforestation And Climate Change Mitigation

Excessive carbon release is a major driver for global warming, and this is where we can use reforestation to combat climate change. How does reforestation affect the carbon cycle? In the process of photosynthesis, trees absorb carbon and convert it into nutrients required for their development. The younger the forest, the more carbon it can store. Basically, kiln-dried wood is about 50% carbon, which means that trees’ ability to accumulate carbon is impressive ^{Lamlom, S., Savidge, R. A. (2003, October). A reassessment of carbon content in wood: variation within and between 41 North American species. Biomass & Bioenergy, 25(4) 381-388. https://doi.org/10.1016/S0961-9534(03)00033-3.}. Furthermore, much carbon is sequestered in forest soils. Thus, reforestation helps to reduce the effects of climate change all across the world in the long run.

Improving Air Quality

Photosynthesis explains another advantage of reforestation since plants not only absorb carbon but also release oxygen, maintaining the balance. For this reason, forests are known as the lungs of our planet. Correspondingly, the more forests we have, the purer the air we breathe. Also, reforestation is efficient in preventing dust storms, adding to air purity.

Enhancing Biodiversity

Woods fascinate with their ecosystem variety, and one of the richest communities is found in tropical forests. In particular, Amazon rainforests count thousands of tree species and 50,000 other plants, apart from abundant fauna.

The World Resources Institute ranked tropical primary forest losses in 2019 as the third-largest in the 21st century ^{Weisse, M., Goldman, E. (2020, June 2). We Lost a Football Pitch of Primary Rainforest Every 6 Seconds in 2019. World Resources Institute.}. In this regard, rainforest restoration is an ultimately significant task nowadays. It combats rare species extinction, both in the kingdom of plants and the kingdom of animals.

Restoring Wildlife Habitats

Forest cuts deprive wildlife of their natural habitat, yet some species can only exist in isolated areas. So, reforestation is essential to preserving their populations.

Maintaining The Water Cycle And Water Quality

Trees store rainwater by absorbing it with their leaves and roots. At the same time, they also release moisture into the atmosphere via transpiration and increase humidity. This way, forests stabilize the air temperature in the nearby locality. They also help to maintain sufficient water levels in local water bodies. Since trees retain moisture and reduce runoff, reforestation also improves water quality and infiltration.

Enriching Soil Fertility

Reforestation contributes to soil health for several reasons:

• It is a habitat for soil microorganisms that participate in decomposition, boosting fertility.
• Fallen leaves and branches form the organic matter.
• Strong root systems hold the earth in place and prevent erosion and landslides.
• By reducing water runoff, trees conserve nutrients in the soil.

Flood Prevention

Trees not only absorb moisture but also make a barrier for water flow during floods or downpours. Thus, they slow down the speed of currents and improve water absorption. By impeding floods, reforestation mitigates damage and losses.

Reversing Desertification

Bare soils are prone to wind and water erosion, which leads to desertification. Reforestation addresses the issue in two ways: with tree roots and the vegetative cover of the forest floor.

Methods Of Reforestation

Planting takes place in two ways: either naturally or artificially. The natural reforestation process relies on the rooting of seeds and sprouts from nearby trees without human assistance. Yet, natural reforestation is insufficient and should be supported by other techniques when tree replacement involves the participation of people.

Reforestation is a routine operation for designated forest farms. Their optimal approach combines reforestation and deforestation when forests are cut in a way that helps establish new ones. The idea is to turn the end into the beginning whenever possible.

There are two classification options for reforestation techniques, depending on the age of co-existing trees:

• even-aged stands: mature overstory is removed to let the new stand grow;
• uneven-aged stands: older and younger trees grow together.

Both of them are used throughout the USA. The choice depends on whether the species can grow in shelter or not and the climatic peculiarities of the region. This is how deforestation gives rise to new tree stands when the remaining mature trees promote new generations. They provide seeds, wildlife habitat, shelter from excessive sunlight or wind, etc.

Uneven-Aged Methods

The uneven-aged system suggests selective cutting a group of trees or individual trees, providing space for a new stand.

The area size in group cuts differs by width and can reach two heights of mature trees. The width depends on the amount of light the species requires. Spruce, fir, maple, hemlock, and red cedar can tolerate shade and will do with a smaller opening. Oaks, loblolly pine, and Douglas fir need more light and, correspondingly, more space. The group selection covers the whole forest tract.

The single-tree reforestation technique chooses separate trees of all sizes and cuts them evenly through the patch. Since the opening is too narrow, the method is suitable only for shade-tolerant species (e.g., hemlock, sugar maple). It also applies to frosty or dry areas.

Even-Aged Methods

The even-aged system is used to provide sufficient sunlight for saplings. It includes clear-cutting, seed tree, and shelterwood options.

Clear-cutting is the complete removal of mature overstory trees to let new trees grow. However, some trees may be preserved as shelter for wildlife or riparian buffers. This is a popular reforestation method to regenerate aspen, yellow poplar, white birch, Douglas fir, red and white oak, jack pine, etc.

Reforestation is performed via natural or direct seeding, sprouting, or planting. In some cases, it can be enhanced with a stronger planting material (genetically improved).

A seed tree implies leaving several mature trees for seeds (6–15 per acre). Typically, they are cut after the seedlings root or left for wildlife or landscape aesthetics. The seed reforestation technique can be combined with planting if natural seeding is not enough. Seed tree reforestation is good for some species of pines and oaks.

Shelterwood suggests growing saplings with mature trees that provide shelter. The method includes three typical stages:

• preparatory cut for better seed production;
• establishment cut that supplies seeds;
• removal cut-off of mature trees to eradicate competition with seedlings.

The method is used for sugar maple and some types of oak and pine.

Challenges In Reforestation

Although reforestation can bring about numerous benefits, it is not without complications. The process of reforestation is highly dependent on weather conditions, the presence of pests and weeds, and the need for consistent maintenance. When discussing the cons of reforestation, it’s important to note that it can be a time-consuming endeavor and, in many cases, cost more than the land’s present use.

This practice extends beyond the mere selection of tree species and delves into the realm of environmental ethics. While considering which tree species to plant, one inevitably ponders the underlying purpose of the reforestation efforts. For preserving biological diversity, it is important to use local, native species and ensure that your reforestation strategies are in line with the local ecosystem.

Сhoosing The Right Tree Species For Reforestation

Not all trees are equal in their growth rate and capacity to take in carbon dioxide (CO2). However, it is possible that planting the fastest-growing and fastest-storing trees can actually work against your environmental goals by having a negative impact on local biodiversity ^{Cunningham, S. C. et al. (2015, July). Balancing the environmental benefits of reforestation in agricultural regions. Perspectives in Plant Ecology, Evolution and Systematics (PPEES), 17(4). https://doi.org/10.1016/j.ppees.2015.06.001.}. There may be unintended consequences for biodiversity if fast-growing trees for reforestation like pines and eucalyptus are used to store carbon quickly. It’s also worth noting that monoculture plantings, the most common method used in reforestation programs, can’t bring back the diverse ecosystems that were lost as a result of deforestation.

The faster rate of decomposition seen in non-native plants compared to native ones often results in increased CO2 emissions. This shows how important it is to pick the right tree species. Any business serious about reducing its carbon footprint should conduct a study of tree species suitable for the local environment and plant only them.

Further Care And Scouting Of Tree-Planting Sites

Reforesting an area isn’t sufficient on its own. The loss of trees and the subsequent release of carbon could result from inadequate site preparation and upkeep. Therefore, protecting young trees from being cut down by illegal loggers or killed by diseases and other threats is essential.

Low Carbon Uptake By Young Trees

Newly planted trees absorb almost no carbon. So, the beneficial impact of reforestation on the environment, such as lower carbon dioxide levels in the air, may not be seen for 20 to 30 years. Here, the strategy of reducing the deforestation of older trees, which absorb far more carbon dioxide, overcomes the program of replanting. However, given the current state of affairs and the actual consequences of deforestation, the optimum course of action is a mix of anti-deforestation efforts and intentional reforestation.

Reforestation Management

Positive reforestation effects are more obvious with proper forest management. So, first, it is important to develop a reforestation plan depending on your purpose (restoration after illegal deforestation, harvesting, wildfires, etc.). With different reforestation purposes, the best trees for planting will be different, too. There is no universal answer to which species to choose since some are the most carbon-absorbing while others are the fastest-growing.

Another discussion point is whether or not reforestation can restore the ecosystem of the previous forest. Here, it depends on the species again. A single tree type will create a monoculture forest, while multiple species will enhance biodiversity. Monoculture forests are more susceptible to tree diseases and other unfavorable conditions, while polyculture forests have more chances to survive. Besides, clear cuts or prescribed fires prove to be an efficient means to speed up natural restoration and ecosystem diversification.

Reforestation management and monitoring are easier with remote sensing, especially in hard-to-reach places. With the satellite-based EOSDA Forest Monitoring solution, you can monitor reforestation progress, receive timely notice if things go wrong, and react accordingly. Low- and medium-resolution remote sensing can detect the changes after 1-2 years of tree planting, while high-resolution remote sensing can provide information much earlier.

Monitoring Reforestation With Vegetation Indices

EOSDA Forest Monitoring uses satellite-based vegetation indices to track the condition of newly planted forests. It helps locate regions with unhealthy canopies, allowing foresters to take prompt corrective action to preserve tree life there.

You may get a clearer view of a forest’s overall health and productivity with the help of vegetation indices, which provide information on a wide range of factors relevant to forests. A decline in NDVI values, for instance, may arise from logging (both legal and illegal), forest fires, storms, chemical overuse, or pest infestation. Also, low NDVI readings may indicate the possibility of droughts or extreme dryness. With timely data that indicates specific problem areas, you can spot-check them, zero in on the source of the problem, and devise a workable solution.

The NDMI index serves to assess the level of water stress. This indicator can be used to determine if there is a shortage or an abundance of water. Leveraging processed satellite images from EOSDA Forest Monitoring, forest managers can examine expansive forest areas and pinpoint trouble spots for developing more targeted tree protection strategies.

Reforestation Detection

Using satellite imagery, our technology can pinpoint the exact location of reforestation inside a specific area of interest (AOI) or across any larger area. We have the technological know-how and the satellites (both free and for a price) to detect reforestation, including the Sentinel-2 optical satellite, the Sentinel-1 radar satellite, and our very own EOS SAT-1, to accommodate any budget.

In addition, the frequency with which we check in on the client’s AOI is adjustable inside our solutions. From platform-based visualization to data via an API to custom charts by email or file-sharing site, we can adapt reforestation report delivery to meet the needs of each client.

On request, EOSDA Forest Monitoring may perform these and many other tasks helpful for monitoring forest stands, such as deforestation monitoring, classifying tree species, determining the area of forest cover on your site, and developing a map of forest cover for any location of interest. Send us a message at sales@eos.com, and we’ll fill you in on everything our product has to offer.

Why Is Reforestation Important?

The importance of reforestation is explained by the role trees play on our planet. New forests help prevent soil erosion or desertification; they are important to protect buildings and fields from winds. Trees along river banks or shorelines fortify and stabilize the coastal area. Woods are natural habitats for unique species that, in some cases, cannot be found anywhere else. This is why it is important not only to regenerate the degraded or destroyed areas but also to plant new ones to refresh the tree cover.

For environmental and human reasons, rapid reforestation is essential for bringing forests back to their pre-deforestation levels of functionality. This is critically important because climate change threatens future access to both seeds and favorable growing conditions ^{Nature’s Benefits: Reforestation. (2020, December 15). Forest Service, U.S. Department of Agriculture.}. In the short term, reforestation is favorable for climate change mitigation while also helping create a low-carbon economy and enhancing global environmental conditions in the long run. Though reforestation already plays a pivotal role in the reduction of carbon emissions, its efficacy can be enhanced through meticulous planning and ongoing monitoring.