Human activities are releasing greenhouse gases into the atmosphere at a growing rate, causing global temperatures to rise and altering the climate over the long term.
In addition to protecting biodiversity, reforesting lost forests can fight climate change by removing huge amounts of carbon dioxide from the atmosphere.
Our planet is facing an emergency. Drought-stricken landscapes are ravaged by wildfires, sometimes spreading to towns and causing them to burn. Tropical storms and floods submerge our neighbourhoods, causing millions of deaths. New tropical diseases increase the possibility of future epidemics and pandemics. There are millions of species at risk of extinction, and global inequality threatens basic human rights. Global climate change and biodiversity loss are causing these problems, which require urgent solutions and action.
To address these global challenges, we often talk about high-tech solutions. Elon Musk, for example, recently announced that he would award 100 million USD for the best carbon capture technology. It is right that we invest in new technologies to curb climate change, but these technologies are still in development. Increasing and implementing these high-tech solutions will take time, and time isn’t on our side. We need urgent actions now, and our best bet is still in low technological, nature-based solutions that are available for implementation right now.
Our biggest problems can be solved by trees naturally. It is great at capturing carbon from the atmosphere and releasing oxygen. In addition to providing habitat for endangered species, they also provide a livelihood for those living in poorer areas. Moreover, tree covers in cities also protect urban residents from the effects of global heating. Forests and trees provide countless ecological, economic, health, and social benefits, yet deforestation is a global issue, especially in the tropics.
Governments and companies worldwide recognize the importance of forests, and have pledged (time and time again) to help stop and reduce deforestation. One such pledge is the 2014 New York Declaration on Forestry, which aims to reduce deforestation by half by 2020 and end it by 2030. Unsurprisingly, this declaration has already failed its 2020 target! Its own 2019 Progress Assessment concluded: “Tropical deforestation has continued at an unsustainable pace since 2014.” The alarming global deforestation rate means we’ve already lost a significant portion of our forest that needs restoration immediately. Over sixty countries are currently restoring 210 million hectares of degraded and deforested land.
It turns out that forest restoration isn’t as simple as people think. A simplistic approach to reforestation can lead to catastrophic failure on key objectives. Poorly planned reforestation attempts can result in the displacement of native biodiversity by invasive species, reduced croplands and food production, disruption of the water cycle, and decreased carbon storage in biomass and soil. Tree plantations usually go wrong due to monoculture plantations rather than restoration through a mix of native tree species.
That’s why a group of scientists have now come up with ten “golden rules” for reforestation designed to increase carbon fixation, increase biodiversity and provide sustainable livelihoods. The researchers hope that their golden rules will serve as a useful guide for policymakers, advisors, and practitioners of reforestation, to avoid many pitfalls of large-scale tree planting.
Deforestation is a global problem that causes land degradation and biodiversity loss.
Recent coverage has focused on whether planting trees is the most effective way to combat climate change. It is certainly important to capture greenhouse gases in the atmosphere and return them to the ground. Trees can help us achieve this goal. Research suggests that the most effective way to reduce atmospheric greenhouse gases is to stop using fossil fuels. See my blog: Planting trees is vital, but it won’t stop climate change. We must reduce fossil fuel use.
Yet, I believe these aren’t binary oAs part of an effective response against the climate emergency and biodiversity crisis, we must immediately reforest and plant trees on degraded lands; prevent any further deforestation; and reduce our dependence on fossil fuels, eventually ceasing to use them.ptions; we must aggressively pursue all strategies in order to overcome the global crisis that we face. To deal effectively with the climate emergency and biodiversity crisis, we need to immediately restore forests and degraded land with reforestation and tree planting; prevent further deforestation; and reduce our dependence on fossil fuels, eventually phasing them out.
Anyway, the purpose of this blog is to highlight the best approach to tree planting. See the headings below for my summary of the 10 Golden Rules for Reforestation.
1. Preserve existing forests first
When planning reforestation, ensure that existing forests are protected, including old-growth and second-growth, degraded and planted forests.
Despite efforts to prevent deforestation, we’re losing forests rapidly – and reforestation isn’t exactly compensating for the damage. As a result, both national and local action is needed to protect forests. Often identifying why deforestation is taking place amongst all stakeholders is key to protecting forests at the local level.
Intact, mature forests are significant long-term carbon sinks due to their complexity, large trees, accumulating soils, and resilience to fire and drought. Destruction of such virgin (old-growth) forests may take centuries to recover, especially for rare and vulnerable species. Of course, once extinct, these species will never return. These intact, old-growth forests offer the greatest value in carbon storage and wildlife, so we must prioritise their protection. Also needing protection are forests that have grown after recent disturbances (second growth forests), degraded and logged-over forests.
2. Cooperate with each other
Make sure to involve all stakeholders and local people in the project.
The livelihoods of many individuals are impacted by reforestation projects. The scale and goals determine who should be involved in the project. There’s no need to engage widely to reforest smallholder farms, whilst large-scale reforestation requires extensive engagement. Stakeholders who are likely to have an interest in reforestation are those that are most likely to be impacted. The list includes national and local governments, forestry departments, NGOs, civil society organizations, the private sector, as well as universities, botanic gardens, herbaria and other research institutes.
Local communities have the most to gain from forest protection and reforestation projects. Involving the locals from the planning stage through to delivery and monitoring is vital for successful outcomes. Increasing community participation improves positive outcomes, including community wellbeing, equitable distribution of benefits and knowledge. Passive participation can lead to community hostility and disputes over access rights. Before planting any trees, stakeholders should agree on how the costs and benefits will be shared. Reforestation projects are more likely to fail if local communities and project managers have different priorities.
4. Maximize biodiversity recovery so that multiple goals are met
By restoring biodiversity, we can achieve other objectives – carbon sequestration, ecosystem services, and socio-economic benefits.
Reforestation is not the goal itself but a way to achieve different objectives. Reasons for reforestation include climate change mitigation, biodiversity conservation, socioeconomic benefits (including food security), and soil and water stability. Of course, different priorities of reforestation will involve different strategies and stakeholders. Therefore, knowing the reforestation goals before planting trees will help appropriate project planning, implementation and monitoring success.
Reforestation through native forest approach often allows high levels of biodiversity, making it easier to achieve multiple objectives simultaneously. If the same native species aren’t available for forest restoration, then other native species may be the best bet. Selecting tree species to reinstate forest cover requires using scientific evidence.
During reforestation projects, it is critical to never harm local communities, native ecosystems, and vulnerable species.
4. Select areas that are suitable for reforestation
Make sure you don’t cultivate previously non-forested areas, connect existing forest areas, and avoid displacing activities that will result in deforestation elsewhere.
Even though there are several tree-planting initiatives globally, reforestations require implementation at a local scale. Therefore, forest restorations require evaluation at the landscape level or below. Selecting areas for reforestation should consider a combination of historical, ecological and socioeconomic factors at different scales. Some tools and resources are available to help guide these decisions, but there’s a need for more. For example, the Restoration Opportunities Assessment Methodology helps quickly identify and analyse areas for reforestation at a national and local level.
Generally, it’s more beneficial to re-establish forests in areas that were previously forested, but are now degraded. Reforestation should not take place in non-forested areas such as grassland, savanna, wetlands and peatlands. Such areas are rich in biodiversity and store a significant amount of carbon in soils, which would otherwise be lost by planting trees. Therefore, tree planting initiatives need to define “no-go zones”, where restoration should focus on non-forest vegetation.
Ideally, tree planting should expand existing forests. Creating buffer zones and corridors between the restored land and existing natural forests allows native species to migrate and expand their distribution. Finally, it’s vital to consider who is currently using the land, how will they be compensated for income losses, and where will they move their activities? Not considering these factors can result in social conflicts, further deforestation or the user reclaiming the land later. Land tenure and forest governance are vital for the success of reforestation.
Reforestation projects require the knowledge and contribution of indigenous, local people.
5. Whenever possible, use natural regeneration
When site and landscape conditions are suitable, natural regeneration can be cheaper and more effective than tree planting.
A forest’s natural regeneration offers significant benefits compared to plantations in terms of carbon capture, biodiversity richness and affordability. Natural regeneration ranges from no human intervention to high intervention, where parts of the site undergo intensive plantation to enable the rest of the land’s natural regeneration.
Degree of degradation and previous land use affect regeneration potential. Soil quality, landscape and hydrological features are other factors that determine the level of human intervention required. Sometimes, a single large site may need different levels of intervention within it.
6. Plant the right species to increase biodiversity
Plant a mix of native species, prioritize mutualistic interactions, and exclude invasives.
If natural regeneration isn’t possible (Golden Rule 5), trees should be planted after carefully selecting plantation species. Selecting a mix of species (either with native species only or a mix of native and non-native) will make the forest more resilient to disease, fire and extreme weather events. Monoculture plantation and planting invasive species should be avoided.
When selecting tree species for plantation, it’s also important to consider tree species’ adaptability to climate change. If the effect of climate change has an impact on native species, then non-native species that preserve the ecosystem function may be the best option. Selecting non-native species for reforestation requires carrying out comprehensive risk assessments.
Several tools and databases available can help in selecting tree species for planting. For example, the Global Tree Assessment aims to provide conservation assessment of all tree species. The GlobalTreeSearch database can help identify the distribution of tree species worldwide and generate a list of native species for each country. Local botanical experts and ecologists also offer invaluable knowledge of the local ecosystem, which can help select native species for plantation and forest recovery.
Scientists recommend a mixture of 20–30 species (mostly native) for plantation for biodiversity recovery. However, maximising biodiversity depends on the mutualistic interaction between the native trees with other species in the ecosystem, such as fungi, seed-dispersing animals, and pollinators. These interactions are vital for ecosystem recovery, but they rarely get the credit they deserve.
In heavily degraded plantation sites, it’s difficult for rare and threatened to establish themselves. Therefore in such cases, it’s effective to plant the fewest native trees that can survive and grow in unfavourable conditions first. This approach will complement and promote natural regeneration and recapture the site from weeds in 2–3 years. Once the forest is an appropriate maturity, it’s best to introduce rare and threatened species. Conservation of vulnerable species requires such an approach to protect them and ensure that they have the best survival chance.
7. Select plants with a high resilience
To maximize population resilience, choose seeds or seedlings with appropriate genetic diversity and provenance.
Selecting genetically diverse species, consistent with local and regional genetic variation, is important for the planted forest’s survival and resilience. Using seeds with low genetic diversity can result in the planted forest being disease-prone and unable to adapt to long-term environmental changes. Therefore, seed collection strategy should include randomly collecting seeds from many individuals across the full extent of the parent population, including rarest species.
8. Plan ahead for infrastructure, capacity and seed supply
From seed collection to tree planting, develop the required infrastructure, capacity and seed supply system well in advance, if not available externally. Always follow seed quality standards.
Whether reforestation involves planting trees or seeds, they require infrastructure and supply systems. An advanced decision is required to determine whether to get seeds and produce seedlings yourself; subcontract these tasks; or buy plant material from external suppliers. Seeds from a third party, usually by state agencies or commercial suppliers, can come directly from the wild or wild-origin seed orchards.
However, if the seed suppliers fail to meet plant material requirements (Rule 6 and 7), projects need to collect, store and propagate seeds themselves. This requires equipment, storage facilities and specialist knowledge for collection from trained seed collectors. National legislation and local laws on access to biological material and international seed standards must always be followed.
Planting seeds directly requires the seeds to be primed for optimal germination and protected from predators and diseases. Seeding requires a plan, including site preparation and seeding strategy, as well as monitoring after planting. Sapling plantation requires an in-house nursery or equivalent.
No matter what the plan is, it’s important to include infrastructure and expertise requirements right from the start. Often local people can provide a source of labour and expertise and facilitate infrastructure arrangements, so it’s important to engage with them properly.
The forest contains a wide variety of species and biomass that provide several ecological services and benefits.
9. Perfect practice makes perfect
Restoration interventions should be based on the best ecological evidence and indigenous knowledge. Before applying techniques on a large scale, perform trials. Monitor appropriate success indicators and use the results to adjust management.
Implementation of any intervention should be based on scientific evidence and indigenous knowledge. Where scientific evidence isn’t available or takes time to generate, traditional knowledge acquired over many generations is beneficial. Ideally, large-scale tree planting should follow on from small-scale trials, which confirm the approach’s effectiveness. However, trials take time and aren’t always feasible, so it’s important to monitor progress and adapt the strategy if needed.
Three things are important to monitor forest restoration: (1) the restoration site itself; (2) control site without any intervention; (3) reference forest site (target). Comparing the restoration site with a control site allows seeing the improvement, and comparing the restoration site with the target site allows seeing progress against the end goal. Data should be collected before, just after restoration intervention, and annually thereafter.
Biomass and biodiversity are usually the best indicators to monitor since they provide several ecological and socioeconomic benefits. Biomass is estimated from stocking density and tree sizes in sample plots, whereas plants and birds usually are monitored for biodiversity recovery. Monitoring should also assess progress against reforestation goals, such as the recovery of endangered species, erosion control, or livelihood benefits (jobs created, income and equity). Socioeconomic monitoring is also important to track the beneurcesresource values have no negative social consequences.
Monitoring generates information for future adaptations – of course, if reforestation is not achieving key objectives, then changes are needed.
10. In order to generate income for all
Create diverse, sustainable income streams for stakeholders, including carbon credits, non-timber forest products, ecotourism, and marketable watershed services.
Reforestations are more likely to succeed in the longer term if the restoration’s income exceeds those from alternative land uses. Income must be shared fairly amongst all stakeholders, including the poorest.
Biomass accumulation and biodiversity recovery are the two most important indicators of restoration that generates a value of forest ecosystem services. Ecotourism, watershed services (water purification, groundwater, erosion control etc.), non-timber forest products, and carbon credits are examples of ecosystem services that offer ways to monetise forest restoration.
The guidelines demonstrate that reforestation is more complex than many think, and that involving many stakeholders at every phase of the process will yield long-term benefits. A post-COVID green recovery can improve global ecology and local livelihoods by reforesting on a large scale. This can only be accomplished with sound science, indigenous knowledge, local community support, equitable governance, and the right incentives.
Scientists have proposed these golden rules for reforestation to maximise carbon capture, biodiversity recovery and livelihood benefits. Let’s hope that it will help turn the hope of global forest restoration into reality.
Read the full scientific review “Ten golden rules for reforestation to optimize carbon sequestration, biodiversity recovery and livelihood benefits,” here: https://doi.org/10.1111/gcb.15498
Originally published at https://gardenstool.shop/ on FebruaryJune 1, 2021.