Letting Nature Regrow Is the World’s Best Hope for a Healthy Future

Mangroves grow along the beach of Tarawa in Kiribati. Photo credit: ADB.
Mangroves grow along the beach of Tarawa in Kiribati. Photo credit: ADB.

Published: 17 December 2020

Protecting ecosystems is real development, and it has an amazing return on investment.


Building infrastructure for human needs—roads, power generation, health and sanitation, townships, and housing settlements—is intended to uplift people from poverty and improve quality of life. However, the unprecedented increase in population and corresponding rate of urbanization and infrastructure growth have placed us on a path toward ecological collapse.

It is estimated that about 50% of our planet’s land is degraded.  Every minute, tropical forests are converted by industrial logging, urbanization, agriculture, and infrastructure building. To date, less than 20% of the world’s remaining forest areas are considered intact.[1] Even within protected areas, 6 million square kilometres (32.8%) of land is under intense human pressure.[2]

In 2010 in Nagoya, during the World’s Conference of Biological Diversity, governments agreed on an ambitious plan to protect biodiversity, adopting 20 Aichi Targets to ensure resilient ecosystems by 2020. The UN Global Biodiversity Outlook 5 released in September concluded that we have not met any of them.

The coronavirus disease (COVID-19) pandemic, which is linked to rampant deforestation and unhealthy consumption habits, is an example of how our relationship with nature is close to passing a point of no return.  

Our greatest challenge is to find a way to harmonize development and technological progress with protecting and conserving natural capital.

Scientists are pushing for at least 30% of the world to become a protected area by 2030, using protected areas and other effective area-based conservation measures (OECMs). We have a long way to go with only about 15% of land and 7.6% of oceans designated or proposed for protection (Figure 1). Most of the world leaders have endorsed the pledge to reverse biodiversity loss by 2030.

Figure 1: Percentage of Marine and Terrestrial Protected Areas

OECM = Other effective area-based conservation measures.

Opposition to the scientists’ proposal relates mostly to the costs involved and to concerns over potential economic losses for the global agriculture, forestry, and fisheries sectors. However, an independent study led by the University of Cambridge forecasts costs to reach only between $103 billion and $178 billion. This includes $68 billion for the existing system, of which only $24.3 billion is currently spent. Expanding the protected areas to 30% would generate higher overall output (revenues) than non-expansion—an extra $64 billion to $454 billion per year by 2050. In the tropics, focusing on protecting 30% of forests and mangroves alone would have an avoided-loss value of $170 billion to $534 billion per year by 2050 by preventing damage from flooding, soil loss, and coastal storm surge and mitigating climate change impact. The value would even be higher when all biomes[3] are considered.[4]

We can afford to prevent an ecological collapse—and most likely the end of human civilization as we know it, but a major change of the way we define “development” is of paramount importance.

Modelling Different Restoration Scenarios

Protecting and restoring only 15% of converted lands in priority areas (to achieve the total 30% of global protection) could avoid 60% of expected extinctions while sequestering 299 gigatons of carbon dioxide (CO2), which is equivalent to 30% of the total CO2 increase in the atmosphere since the Industrial Revolution.[5]

Multi-criteria analysis, which considers the contribution of different ecosystems’ restoration to the Aichi Targets, will need to consider (i) the potential to mitigate climate change, (ii) avoiding biodiversity losses, and (iii) minimizing costs.

The least-cost option (estimated at around $2,356 per hectare) may be significantly cheaper, but in environmental terms, it will deliver only 34% and 39% of the potential benefits for biodiversity and climate (Figure 2).

Figure 2: Outcomes of Restoration for Biodiversity (a), Mitigating Climate Change (b) and Minimizing Opportunity Costs (c)

Source: Strassburg et al., 2020.

Strong policies and international cooperation are fundamental to achieving these targets. The prioritization of areas to restore and protect does not consider national borders but biomes that are often distributed between different countries, and not always equally (Figure 3). Under the best-case scenario, some countries will need to protect or restore a larger fraction of their territories.  This will entail higher initial costs but also higher advantages in terms of avoiding future economic losses. If a global agreement cannot be reached, and the 15% target will need to be achieved for each individual country, it would result in a 28% reduction in benefits for biodiversity and 29% for climate, while increasing costs by 52%, compared with the best case scenario.

Financial mechanisms to help developing countries achieve these objectives are available but need to be strengthened.

Figure 3: Global Priority Areas for Restoration

These are based on maximizing outcomes for biodiversity, climate change mitigation, and opportunity costs. High priority areas include most of Southeast Asia, the Himalayas, Central America and the Caribbean, West and Central Africa, and areas around the Amazon and the Mato Grosso in South America. Adapted from Strassburg et al., 2020.

The Asia–Pacific region is critical to achieving the targets. Its growing population requires more and more space for agriculture and extracting natural resources while urbanization and migration to cities are driving demand for more infrastructure under a business-as-usual scenario. Tropical forests and peatlands—which are rich in biodiversity and store large quantities of carbon—are under extreme pressure.

The Solution: A Regenerative Approach to Development

The restoration of damaged ecosystems and the protection of existing natural areas must be recognized as part of sustainable development and included in a country’s development plan. Wilderness areas should not be considered “underdeveloped” but rather as critical for human well-being. This paradigm shift is key to both mitigating climate change and halting the biodiversity crisis.

How can we achieve the ambitious target of converting 30% of our planet into protected areas by 2030?  Here are some ideas:

1. Include environmental costs in infrastructure and agricultural development planning

The encroachment of human activities into natural areas cannot continue to be overlooked. Serious indirect impacts include deforestation, habitat loss, hunting and poaching of wildlife, and release of greenhouse gases. Environmental costs linked to these developments are almost never taken into consideration during the planning and feasibility phases.  Existing market and land-policy distortions undervalue the use of natural resources, making business-as-usual systems more competitive in the short term. For example, even without the expansion of croplands, thanks to better agricultural practices, today’s global biomass potential exceeds future (peak) demands of 10 billion humans on the planet.[6]

The loss of natural areas must become unacceptable in national strategies and policies, from both an economic and environmental point of view. The COVID-19 pandemic—which available evidence suggests is a zoonotic disease that originated from contact between a wild animal and a human—shows that investing in the health of natural ecosystems has a remarkable return on investment.

2. Embrace traditional and indigenous knowledge

Eighty percent of the world’s remaining biodiversity is in indigenous people’s lands.[7] Nature is better preserved in these lands,[8] yet traditional and indigenous knowledge is often overlooked, if not ignored. Recognizing indigenous peoples’ rights to land, benefit sharing, and institutions are essential to meeting conservation goals, including restoration and protection of wilderness areas. Indigenous land management conserves biodiversity, store carbon, maintains a range of vital ecosystems services, safeguards rich cultures and traditional ways of life, and responds to the needs of the most vulnerable.

3. Mainstream land protection and restoration into development plans

An estimated 287 million hectares of degraded land in the tropics could be restored to continuous, intact forest. Restoration plans can create jobs through replantation activities, endemic plant nurseries, and invasive species eradication and control. Revenues from domestic and international tourism are also expected to increase, providing further benefits for local communities.

Avoided-loss values of forest regeneration are calculated to be in the billions of dollars worldwide. Tropical forest regrowth, especially if assisted, is often rapid and results in carbon sequestration rates of 1.4 tons per acre annually. Considering all different actions related to land restoration and protection, the benefits in terms of climate change mitigations are remarkable (Table 1).

Table 1: Gigatons of CO2 Equivalent Reduced/Sequestered (2020–2050)

Solution Scenario 1 Scenario 2
Tropical Forest Restoration 54.45 85.14
Peatland Protection and Rewetting 26.03 41.93
Tree Plantations (on Degraded Land) 22.24 35.94
Temperate Forest Restoration 19.42 27.85
Conservation Agriculture 13.40 9.43
Abandoned Farmland Restoration 12.48 20.32
Indigenous Peoples’ Forest Tenure 8.69 12.93
Forest Protection 5.52 8.75
Grassland Protection 3.35 4.25
Coastal Wetland Protection 0.99 1.45
Coastal Wetland Restoration 0.77 1.01
Total 167.34 249.00

Scenario 1 is in line with a 2˚C temperature rise by 2100, while Scenario 2 is in line with a 1.5˚C temperature rise at century’s end.
Source: Project Drawdown.

4. Establish a “Paris Agreement” for biodiversity

Starting from lessons learned from the Paris Agreement on Climate Change, the Conference of the Parties of the Convention on Biological Diversity should reach an agreement on a global target. Countries can make voluntary pledges to meet the goal like the Nationally Defined Contributions (NDCs) of the Paris deal. Participating countries should declare their own national biodiversity targets, policies, and timelines, subject to a periodic review, for attaining the overall target. Wealthier countries should also include financial and technological commitments to assist biodiversity conservation in developing economies through the Global Environment Facility (GEF), international financial institutions such as the Asian Development Bank, or bilateral pledges.

5. Involve the private sector in conservation and restoration of ecosystems

The global biodiversity crisis is in large part due to the lack of international commitment and funding over the past 25 years. It is unlikely that developing economies will be able to fund significant actions against biodiversity loss. However, corporations (especially those involved in natural resources-based sectors) have strong financial interests in maintaining biodiversity for their own survival and sustainability. For example, protecting habitats of wild pollinators enhances global crop production by $235 billion to $577 billion annually.[9] The seafood production, forestry, and insurance industries have strong interest in maintaining biodiversity for the sustainability of supply chains, and the investments needed are just a small fraction of the revenues derived from healthy ecosystems (Table 2). Other sectors like ecotourism, pharmaceuticals, and fashion can also help fill the financing gap.

Table 2: Financial Benefits from Biodiversity Conservation

Industry Annual Revenues (US$ billion) Benefits from Biodiversity Conservation Conservation Target Potential Investment (US$ billion/year)
Seafood $252 Increase profits by up to $53 billion[10] Increase marine biomass stocks $5–$10
Forest Products $300 Attain sustainable forest management goals[11] Increase area of protected forests $15–$30
Insurance $4,300 Reduce estimated global flood damage losses of $52 billion annually[12] Increase area of protected coastal wetlands $5–$10

Adapted from Barbier et al, 2018.[13]

The United Nations has declared 2021–2030 as The Decade on Ecosystem Restoration  to prevent, halt, and reverse the degradation of ecosystems worldwide. The good news is we have the solutions to fight biodiversity loss and climate change and reduce the damage from too many years of inaction. The first step is to consider restoring forests and ecosystems as developments equal to infrastructure like energy, health, and transport.

[1] O. Venter et al. 2016. Sixteen Years of Change in the Global Terrestrial Human Footprint and Implications for Biodiversity Conservation. Nature Communications. 7.

[2] K.R. Jones et al. 2018. One-Third of Global Protected Land Is under Intense Human Pressure. Science. 360 (6390). pp 788–791.

[3] A large naturally occurring community of flora and fauna occupying a major habitat, e.g., forest or tundra.

[4] F. Harvey. 2020. Protecting 30% of Planet Could Bolster Economy, Study Says. The Guardian. 8 July.

[5] B.B.N. Strassburg et al. 2020. Global Priority Areas for Ecosystem Restoration. Nature.

[6] W.  Mauser et al. 2015. Global Biomass Production Potentials Exceed Expected Future Demand without the Need for Cropland Expansion. Nature Communications. 6.

[7] C.  Sobrevila. 2008. The Role of Indigenous Peoples in Biodiversity Conservation: The Natural but Often Forgotten Partners. Washington, D.C.: World Bank Group.

[8] S.T.  Garnett et al. 2018. A Spatial Overview of the Global Importance of Indigenous Lands for Conservation. Nature Sustainability. 1 (7). 369–374.

[9] S. Potts et al. 2016. Safeguarding Pollinators and Their Values to Human Well-Being. Nature. 540. pp. 220–229.

[10] C.  Costello et al. 2016. Global Fishery Prospects under Contrasting Management Regimes. Proceedings of the National Academy of Sciences. May. 113 (18). pp. 5125–5129.  

[11] International Council of Forest & Paper Associations. 2006. Sustainability Information.

[12] C.S. Colgan, M. W. Beck, and S. Narayan. 2017. Financing Natural Infrastructure for Coastal Flood Damage Reduction. Lloyd’s Tercentenary Research Foundation.

[13] E.B. Barbier, J.C. Burgess, and T.J. Dean. 2018. How to Pay for Saving Biodiversity. Science. American Association for the Advancement of Science.

Ask the Experts

  • Francesco Ricciardi
    Environmental Specialist, Sustainable Development and Climate Change Department

    Prior to joining ADB, Francesco worked as a researcher focusing on the impact of pollution on natural ecosystems and wildlife. After leaving academia, he has worked as environment, ecology and biodiversity consultant in several projects around Asia, including energy plants, coastal infrastructures, and natural resources. He is also a published underwater and wildlife photographer.

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  • Asian Development Bank (ADB)

    The Asian Development Bank is committed to achieving a prosperous, inclusive, resilient, and sustainable Asia and the Pacific, while sustaining its efforts to eradicate extreme poverty. Established in 1966, it is owned by 68 members—49 from the region. Its main instruments for helping its developing member countries are policy dialogue, loans, equity investments, guarantees, grants, and technical assistance.

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