Natural History of Ecological Restoration

Tag: International commitments

Global pledges to restore forests face challenges, and need increased support
Matthew Fagan is an assistant professor in Geography and Environmental Systems at University of Maryland Baltimore County. Here he describes the challenges confronting countries as they attempt large-scale forest restoration, and why many countries will need help to fulfill their goals. For more information, read his new, open-access paper in Conservation Letters.

Degraded and deforested landscapes are widespread, and tropical forests are being lost at a rate of 15.8 million hectares a year. But there is good news—temperate forest area is increasing, and more and more countries are voluntarily pledging to restore vast tracts of degraded land. Restoring forests benefits biodiversity and society, and can combat global warming as well, as growing trees lock away carbon dioxide.

International interest in restoring trees to landscapes emerged out of policy discussions last decade, and resulted in the 2011 Bonn Challenge and the creation of voluntary national restoration targets by many countries. The Bonn Challenge seeks to bring 150 million hectares into restoration by 2020, and 350 million hectarees by 2030 (that’s roughly 700 million American football fields, 350 million rugby fields, 500 million FIFA football fields, or an area a bit larger than India).

Current Bonn Challenge pledges total some 172 million hectares. That’s a massive international commitment, and when you add in internal commitments by countries, the potential restoration area swells to 318 million hectares.

All that area voluntarily committed to restoration got my co-authors and I excited, but also skeptical—were countries really going to follow through on their commitments?

A rain forest blow-down in northeastern Costa Rica, with a storm-downed tree cut to clear a path. Silviculture restoration promotes the recovery of disturbed forests like this one. Photo credit: Matthew Fagan.

To try to answer that question at this early stage, myself, Leighton Reid (Virginia Tech), Maggie Holland (UMBC), Justin Drew (UMBC), and Rakan Zahawi (University of Hawaiʻi at Mānoa) asked three related questions in a recent paper in Conservation Letters.
1. Is the amount of land a country pledged to restore related to their past record of restoring forested landscapes and implementing sustainable development?
2. For the small group of countries that have publicly reported their progress on commitments, is the amount of restoration they completed predictable by their development level or other risk factors, like deforestation?
3. Which countries will likely face the greatest challenges to meet their commitments and maintain restored land into the future?
We then set to gathering published information on country commitments and progress, and recent national rates of forest loss, agricultural expansion, and forest recovery.

Recent natural regeneration in northeastern Costa Rica of varying ages. Photo credit: Matthew Fagan.

All of these programs seek to reforest landscapes in ways that benefit both nature and people, including options like natural regeneration (letting natural forests recover and expand), silviculture (interventions to restore standing forests, like preventing forest fires and promoting recovery from selective logging), tree plantations (often tree monocultures to produce timber and pulp on degraded lands), and agroforestry (planting trees on and around farmland to shade crops or protect streams and fields). These options are not all equal in their benefits for biodiversity, carbon, and society, but a diverse menu of options allows countries to consider committing to at least some form of restoration over large areas.

A tree plantation in northeastern Costa Rica funded by the national payments for environmental services program. It is a monoculture of a single native species, Vochysia guatemalensis, grown for timber. Photo credit: Matthew Fagan.

In a nutshell, what we found was both discouraging and encouraging.

First, after adjusting for the size of a country and how much restoration they had done previously, we found that less-developed countries committed more land for restoration. This might be for positive reasons; for example, they may be taking proactive action against the greater risk they face from climate change. Or it might be because they underestimated how challenging it would be to achieve a large pledge.

Silvopastoral restoration, a type of agroforestry, in northeastern Costa Rica. The understory is a cattle pasture, while the overstory is plantation of a native tree species, Dipteryx panamensis. Photo credit: Matthew Fagan.

Second, for twelve early-reporting countries, restoration progress was predictable based on a risk index. Countries with higher risk (risk factors included deforestation rates and progress on sustainable development goals, among others) had less restoration progress.

Third, countries made massive individual commitments that will be hard to achieve without wholesale transformation of their food systems. One third of countries committed >10% of their land area (with a maximum of 81%, in Rwanda). A quarter either committed more area than they had in agriculture, or committed more area than they had in forest. And one quarter of countries had more forest loss and agricultural conversion in 2000–2015 than their restoration commitment for 2015–2030.

Coffee plantation under tree cover, a type of agroforestry, in central Costa Rica. The understory is a monoculture of coffee shrubs, while the overstory is scattered planted trees. The partial cover helps the shade-loving coffee plants stay healthy, but many coffee farmers are moving away from this traditional farming approach. Photo credit: Matthew Fagan.

As noted in our paper, “If voluntary commitments like the Bonn Challenge fail to precipitate meaningful restoration across large areas, the UN’s vision of a sustainable future will become less attainable.” But what this study found is not countries that have failed on their restoration pledges. We are still in the first days of the UN Decade of Ecosystem Restoration. What we have identified is countries that will need help to restore their lands.

We believe it is time for the international community to step up and aid all countries in achieving their restoration goals. To quote Thoreau, “If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them.”

A regrowing forest in central Costa Rica, showing the promise of restoration. Photo credit: Matthew Fagan.
January 28, 2020
The ephemeral forests of southern Costa Rica

Damaged ecosystems don’t recover overnight, but sometimes that’s all the time that they get. CCSD scientist Leighton Reid describes new research about tropical secondary forests in southern Costa Rica, including how long these young forests last, what’s at stake, and how we can keep them around longer.

Regrowing tropical forests on marginal farm lands is one of the main ways that humans can prevent runaway climate change. With ample moisture and long growing seasons, tropical trees often can grow quickly and pull large amounts of carbon out of the atmosphere, storing it in their wood and keeping it from trapping heat. At the same time, young forests provide habitat for plants and animals and improve water quality for humans, among many other benefits.

But even in a moist, tropical climate, trees don’t grow instantly. Typically, it takes many decades for a recovering forest to stock up all of the carbon that it can hold. And it can take even longer for some plants (like orchids) and animals (like antbirds) to return. If a forest starts to grow back, but then someone cuts it down again, these time-dependent benefits never accrue.

In other words, the hopes and expectations that many people have for young tropical forests depend on young tropical forests growing old. So do they? Our new study suggests not.

The Coto Brus Valley and Talamanca Mountains in southern Costa Rica. Photo by J. Leighton Reid.

To find out how long secondary forests persist, I teamed up with Matthew Fagan, a landscape ecologist at the University of Maryland Baltimore County, and Rakan Zahawi, director of the Lyon Arboretum, as well as two students, James Lucas at Washington University and Joshua Slaughter at UMBC.

We studied a set of historical, aerial photos from southern Costa Rica, which covered the time period from 1947-2014. Previously, Zahawi and colleagues had classified which areas in each photo were forest and which areas were farms or other non-forest land uses. By comparing the maps they made for each year, we were able to see where and when new forests appeared and how long they remained as forest before they were converted to some other land use (mostly farms).

The young forests did not last long. Half of the new forests disappeared before they were 20-years old. And 85% were cut down before they were 54-years old. Larger forests and forests near rivers lasted longer.

An isolated forest fragment surrounded by cattle pastures in southern Costa Rica. Photo by J. Leighton Reid.

First, the bad news. Twenty years is not even close to the amount of time it takes for a young forest to become as diverse as an old-growth forest. For example, vascular epiphytes like orchids and bromeliads take more than 100 years to fully recover in young forests.

Carbon storage will also take a hit. If forests elsewhere in Latin America are as ephemeral as forests in southern Costa Rica, then carbon stocking over the next thirty years may be reduced by an order of magnitude.

Ephemeral forests could just be a problem in Costa Rica, but another study shows that secondary forests in eastern Peru have even shorter lifespans. There, secondary forests are cleared at a rate of 3-23% per year. Compared to that, the 2-3% per year rate of loss in southern Costa Rica is considerably better. And that’s not a good thing. Clearly we need more research on secondary forest persistence from other places.

There is some good news, though. Even though many new forests were short-lived, the ones that survived were predictable. And if we can predict where new forests will survive, we should also be able to help them survive longer. Larger forests and forests close to rivers were cut down less often than small forests and forests far from rivers. This suggests that restoring large, riparian forests could be a smart investment.

Forests and cattle pastures in southern Costa Rica. Photo by J. Leighton Reid.

Governments and other organizations can also help forests persist by creating incentives for long-term forest management, providing resources to enable long-term management, and ensuring that local people will be able to enjoy the benefits that old forests provide.

We hope that this work will lead to stronger restoration commitments. Right now, dozens of countries are setting big targets for forest restoration. For example, in 2012 Costa Rica committed to restore a million hectares of degraded land by 2020 (an area about one fifth the size of the country). There is a great opportunity for Costa Rica and other ambitious countries to plan for long-term forest restoration.

If we can begin to restore a million hectares of forest by 2020, why not plan to restore a million hectares of 100-year old forest by 2120?

A trail through secondary forest at the Las Cruces Biological Station in southern Costa Rica. Photo by J. Leighton Reid.

For more information on this research, you can read our open-access paper in Conservation Letters or watch a video of Leighton Reid presenting to the Association for Tropical Biology and Conservation back in June. Additional papers on restored ecosystem persistence are available here and here. This work is a product of the PARTNERS (People and Reforestation in the Tropics: a Network for Research, Education, and Synthesis) Working Group on Spatial Prioritization. Funding was provided by grant DEB-1313788 from the U.S. National Science Foundation’s Coupled Human and Natural Systems Program.

September 26, 2018
Special Feature: Ecological Restoration in a Changing Biosphere

The following is an introduction by Leighton Reid and James Aronson to a special feature in Annals of Missouri Botanical Garden about ecological restoration in a changing biosphere. The eight papers described are derived from presentations last October at the 65th Annual Plant Symposium. The full issue can be found here.

Restoration efforts will affect large areas of the planet and hundreds of millions of people over the coming decades, but what will these actions look like, and what will they achieve? Debate continues about what constitutes appropriate restoration targets in our human-dominated and ever more rapidly changing world, and the outcome of this debate will impact the actions taken to conserve biodiversity, sequester carbon, and improve human livelihoods at large spatial scales. This special issue brings together eight scientific, historical, and journalistic perspectives to address these two critical questions about ecological restoration in a rapidly changing biosphere.

In the post-COP22 world, when all three of the UN’s “Rio Conventions” call for scaling up and mainstreaming of ecological restoration (UNCBD 2012; UNCCD 2015; UNFCCC 2015), and dozens of governments have made ambitious restoration commitments (IUCN 2016), it is clear that restoration programs will affect hundreds of millions of hectares – and as many people – over the coming decades. At the same time, we find ourselves in an era of unprecedented change where climate, ecological baselines, and future land-use changes are highly uncertain (Steffen et al., 2015). This raises the crucial question: What will large-scale restoration activities look like in the coming years?

Unsurprisingly, there are differences of opinion about the future of restoration and how to scale it up and integrate it with larger programs in an era of major, anthropogenic changes. Hobbs et al. (2011; pg 442) observe that “…the basic principles and tenets of restoration ecology and conservation biology are being debated and reshaped. Escalating global change is resulting in widespread no-analogue environments and novel ecosystems that render traditional goals unachievable. Policymakers and the general public, however, have embraced restoration without an understanding of its limitations, which has led to perverse policy outcomes.” [Emphasis added]

This perspective has received considerable attention (ESA 2016) and also pointed criticism (Murcia et al., 2014). Aronson et al. (2014; pg 647) retort that “…Restoration includes a wide range of practical possibilities for dealing with transformed ecosystems, including rehabilitation, reclamation, and remediation. Some will bring the ecosystem back to its historical trajectory, some will bring back only some attributes, but the intention is that the end product is better than the degraded ecosystem. Importantly, a label such as novel ecosystem implies no need for further intellectual exertion – and ignores the growing science of the young discipline of ecological restoration.” [Emphasis added]

The debate goes on about what we are trying to restore (Hobbs, 2016; Kattan et al., 2016; Miller & Bestelmeyer, 2016), with implications far beyond academia. Billions of dollars are now being spent to rehabilitate and restore degraded ecosystems, sometimes at large scales, and the science of restoration ecology must adapt to be integrated in larger planning and management schemes, wherein conservation, management, and restoration will all take place.

On 8 Oct 2016, we convened a panel of six scientists, one historian, and a journalist, all with long-standing involvement in the field of restoration ecology. The goal was to discuss ecological restoration in a changing biosphere at the 63^rd Annual Fall Symposium at Missouri Botanical Garden. Each speaker has contributed a paper to this special issue.

The first set of papers focus on the question: Has global change outpaced and rendered obsolete the so-called “classical” ecological restoration approach? Aronson et al. (2017) say no, far from it; for example, the historically-based reference system ‒ a pillar of ecological restoration to date ‒ is more valid than ever and can indeed be adapted to landscape and higher levels of complexity. They emphasize that while restoration ecology has produced many useful ecological models, a participatory approach and consensus-building among stakeholders are crucial at these higher levels of integration. Falk (2017), in contrast, says yes: global change calls for radical rethinking of ecological restoration. He focuses on ponderosa pine forests in the southwestern US, which are undergoing a major, climate change-induced biome shift from forest to shrub land, and he concludes that a shift towards resilience-based management is necessary to supplement traditional ecological restoration. Meine (2017) takes the middle ground through an historical analysis; he notes that Aldo Leopold (1887-1948) would likely have concluded that a simple “yes” or “no” was inappropriate and that ecological novelty is neither novel nor absolute.

Whereas the first group of papers asks what we should restore, the second group focuses more on how we will restore at larger spatial and temporal scales. Brancalion & van Melis (2017) suggest that to bridge the gap between science and practice, we need to innovate; rather than refining current approaches, restoration ecologists must look outside of their disciplinary silos for fresh solutions to contemporary dilemmas. One source of new insights will be through joint research between scientists and practitioners. To this end, Holl (2017) presents several new directions for tropical forest restoration research (graduate students – take note!). She emphasizes that for research to best inform practice, it should be conducted at large spatial and temporal scales, research projects should be undertaken jointly with stakeholders, and resulting knowledge should be shared across regions. Chazdon (2017) argues that natural regeneration, more than any other method, is the key for scaling up to efficient forest and landscape restoration, and she emphasizes the need to identify priority areas where natural regeneration is maximally feasible and minimally competitive with alternative land uses. Finally, Reid et al. (2017) argue that however we restore ecosystems, we should plan to make them last; the longevity of restored ecosystems, they suggest, is variable, often finite, and determined to some degree by stakeholder preferences, environmental attributes, and the umbrella of governance. These papers emphasize tropical forest restoration, particularly in Latin America, which is appropriate given this biome’s global importance, yet the topics addressed will be of interest to readers with experience in many ecosystems.

The last word (for this special issue, at least) is left to Paddy Woodworth (2017), an international journalist with broad and optimistic perspectives on ecological restoration (Woodworth, 2013). Looking across the contributions, he observes that the words we choose have meaning and cautions against the use of the word “restoration” for anything less than the process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed (SER 2004).

We hope that readers from many backgrounds, including researchers, practitioners, and policymakers, will find this special issue worth pondering as they move forward with our collective task to progress towards a more sustainable, just, and desirable future.

References

Aronson, J., J. Blignaut & T. B. Aronson. 2017. Conceptual frameworks and references for landscape-scale restoration: Reflecting back and looking forward. Annals of the Missouri Botanical Garden 102(2): 188–200.

Aronson, J., C. Murcia, G. H. Kattan, D. Moreno-Mateos, K. Dixon & D. Simberloff. 2014. The road to confusion is paved with novel ecosystem labels: a reply to Hobbs et al. Trends in Ecology & Evolution 29: 646-647.

Brancalion, P. H. S. & J. van Melis. 2017. On the need for innovation in ecological restoration. Annals of the Missouri Botanical Garden. 102(2): 227–236.

Chazdon, R. L. 2017. Landscape restoration, natural regeneration, and the forests of the future. Annals of the Missouri Botanical Garden. 102(2): 251–257.

ESA (Ecological Society of America). 2016. Ecological Society of America announces 2016 award recipients. The Bulletin of the Ecological Society of America 97: 337-351.

Falk, D. A. 2017. Restoration ecology and the axes of change. Annals of the Missouri Botanical Garden. 102(2): 201–216.

Hobbs, R. J. 2016. Degraded or just different? Perceptions and value judgements in restoration decisions. Restoration Ecology. doi: 10.1111/rec.12336.

Hobbs, R. J., L. M. Hallett, P. R. Ehrlich & H. A. Mooney. 2011. Intervention ecology: Applying ecological science in the Twenty-first Century. Bioscience 61: 442-450.

Holl, K. D. 2017. Research directions in tropical forest restoration. Annals of the Missouri Botanical Garden. 102(2): 237–250.

IUCN (International Union for Nature Conservation). 2016. Bonn Challenge commitments. http://www.bonnchallenge.org/commitments. Date accessed: September 22, 2016

Kattan, G. H., J. Aronson & C. Murcia. 2016. Does the novel ecosystem concept provide a framework for practical applications and a path forward? A reply to Miller and Bestelmeyer. Restoration Ecology 24:714-716.

Meine, C. 2017. Restoration and “novel ecosystems”: Priority or paradox? Annals of the Missouri Botanical Garden. 102(2): 217–226.

Miller, J. R. & B. T. Bestelmeyer. 2016. What’s wrong with novel ecosystems, really? Restoration Ecology 24: 577-582.

Murcia, C., J. Aronson, G. H. Kattan, D. Moreno-Mateos, K. Dixon & D. Simberloff. 2014. A critique of the ‘novel ecosystem’ concept. Trends in Ecology & Evolution 29: 548-553.

Reid, J. L., S. J. Wilson, G. S. Bloomfield, M. E. Cattau, M. E. Fagan, K. D. Holl & R. A. Zahawi. 2017. How long do restored ecosystems persist? Annals of the Missouri Botanical Garden. 102(2): 258–265.

SER (Society for Ecological Restoration). 2004. The SER primer on ecological restoration. http://www.ser.org/content/ecological_restoration_primer.asp. Date accessed: September 28, 2009

Steffen, W., W. Broadgate, L. Deutsch, O. Gaffney & C. Ludwig. 2015. The trajectory of the Anthropocene: the great acceleration. The Anthropocene Review 2: 81-98.

UNCBD (United Nations Convention on Biological Diversity). 2012. UNEP/CBD/COP/DEC/XI/16. https://www.cbd.int/doc/decisions/cop-11/cop-11-dec-16-en.pdf. Date accessed: 12 December 2016

UNCCD (United Nations Convention to Combat Desertification). 2015. Land matters for climate: reducing the gap and approaching the target. http://www.unccd.int/Lists/SiteDocumentLibrary/Publications/2015Nov_Land_matters_For_Climate_ENG.pdf. Date accessed: 12 December 2016

UNFCCC (United Nations Framework Convention on Climate Change). 2015. Paris agreement. http://unfccc.int/files/essential_background/convention/application/pdf/english_paris_agreement.pdf. Date accessed: 12 December 2016

Woodworth, P. 2013. Our Once and Future Planet. University of Chicago Press, Chicago.

Woodworth, P. 2017. Meeting the twin challenges of global change and scaling up, Restoration needs insights from the humanities as well as analysis from science. Annals of the Missouri Botanical Garden. 102(2): 266–281.

August 16, 2017