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The report is strategic and has substance for a diverse audience.

In terms of gaps, I see mapping of suffrutex life forms in floristic groups or the centres for suffrutex (geoxylic) diversity, such as in the miombo (Africa south of the equator) and the Brazilian Cerrado.  In the Zambezian floral domain with at least 121 geoxylic species described, there are endemic species and many of the families represented above ground, even some canopy species, lie in the subterranean flora including Rubiaceae and Anacardiaceae. These include important miombo flowering canopy species such as Syzygium guineense  and Parinari sub species.

It may be meaningful to note the reality of geoxylic diversity not least in quite compact woodland types such as the Miombo across at least 7 countries south of the Equator in Africa  - below and above ground. In the context of climate change narrative, biodiversity and genetic pools, refuges and endemism alongside resilience for adaptation this is an important resource.

Practically speaking, as the mapping process delineates types and extent, woodlands such as the Miombo and Cerrado in Brazil, further work to recognize and value the underground suffrutex vegetation provides a more realistic picture.

The above is based on personal experience of research and bilateral work in Miombo ecozone, although a few years ago. Phil. Tuite (PhD)

English version below

Buenas tardes queridos colegas,

Nosotros aquí en Guinea Ecuatorial, utilizamos la definición de la FAO, es decir, el bosque empieza con 0,5 ha con una cobertura forestal de 10% y altura de los árboles de 5 metros. Es una definición que nos vas a la perfección en cuanto a los bosques primarios se refiere, pero sin embargo, todo lo que son bosques secundarios serían más adaptables con una altura de aboles de 3 metros, porque con el proyecto Regional REDD+ y los Créditos de Carbono, estos árboles también almacenan una importante tasa de carbono, además hay muchos países que también han definido la altura de sus árboles a 3 metros. Pienso que también se debería reflexionar en cuanto a eso.

Muchas gracias

Good afternoon dear colleagues,

Here in Equatorial Guinea, we use the FAO definition, that is, that forest starts with 0.5 ha with a forest cover of 10% and a tree height of 5 meters. It is a definition that suits us very well as far as primary forests are concerned. However, regarding secondary forests it would be more suitable to consider height of 3 meters, as with the REDD + Regional Project and the Credits of Carbon, these trees also store an important carbon rate. In addition, there are many countries that have also defined the height of their trees at 3 meters. I think you should reflect on that.

Thank you

Dear members of the FAO forum,

I’d like to start with a special thank you to all those who have contributed to the forum so far and it is great to see the growing amount of participation. This week there have been many important and thought-provoking points raised. Several commentators have discussed the need for clear thresholds around how much disturbance or the interval of time since disturbance, results in forests not being considered primary. On this topic respondents have raised points, such as the need to consider all human disturbances and at what point does old/ancient damage stop being and important consideration when defining primary forest.

Another issue commonly discussed was the monitoring periods of remotely sensed datasets. In particular the limited timeframes of satellite data for some countries, as this influences the feasibility of these techniques for long-term monitoring of primary forest in these regions.

Although these have been some of the most common discussed topics, the wealth of feedback received was much broader and more detailed. Many thanks to all commentators for their time and effort put into this consultation so far. Over the last five days of the consultation period we welcome and greatly appreciate any further comments and feedback.

Thank you and kind regards

Patrick Norman

Thank you for the opportunity to contribute to this exiting effort and the great work already accomplished. Following are my insights after reading the paper.

What exactly is FAO trying to measure under their definition of Primary Forests? The definition of primary forests is an attempt to envision how forests look like and evolve in the absence of humans or in the presence of human population levels that are perceived as not having an impact on the environment (as a read the exception for indigenous communities). However, we all know that this far from reality. Humans, indigenous or not, have an impact in forests, even in those cases where their presence is remote. Climate change is a good example, as the paper addresses. Another example of indirect impact is when human action pushes species to move to areas less influenced by humans, becoming habitat competitors to other species. This is the cases of the Northern Spotted Owl (Strix occidentalis caurina) and the Barred Owl (Strix varia) in the U.S. The Northern Spotted Owl was listed as “threatened” species in 1990, which lead to changes in land management throughout the U.S. Pacific Northwest and northern California, primarily by curtailing logging of old forests, the owl’s preferred habitat. The assumption was that by reducing habitat loss, primarily on federal lands, population numbers will recover. However, after nearly two and a half decades of protection under the Endangered Species Act, the spotted owl is not showing signs of recovery and, in fact, its situation has worsened. This is due to the arrival of the barred owl, a historical resident of the U.S. eastern forests. At some point less than 100 years ago, barred owls began dispersing towards west. It’s believed that this was due, at least partially, to changes in habitat caused by a cessation of Native American burning in the plains after Europeans and other foreigners arrived. Lack of fire allowed trees to grow creating habitat “bridges” across the plains that facilitated barred owl movement. Barred owls were first reported in northern British Columbia in 1949; today they overlap the entire range of the northern spotted owl. As a result of the barred owl migration to the west and their biological advantages over the spotted owl, populations of spotted owl are rapidly declining in many areas.

The extend of human footprint on the environment is broad and complex both in space (scale, direct and indirect impacts) and time. Given the latest adopted definition states: "Naturally regenerated forest of native tree species, where there are no clearly visible indications of human activities and the ecological processes are not significantly disturbed." The definition is confined to human visibility/perception. Does the definition focus on forest appearance to the human eye or on ecological resilience/health (significantly disturbed)?

Philosophically, Primary Forest attempts to capture those forest tracks that remain “pristine”, “virgin”, “not exploited/modified by humans”. The definition embraces the underlying assumption that human impact is negative (or at least not as good as nature), but in some cases human action is ecologically beneficial. What is the ecological difference between a natural disturbance and a silvicultural prescription that mimics nature? For example, is there any difference between a natural low intensity fire and a prescribed fire? If human intervention through silvicultural practices can accelerate forest successional stages, why this is not capture in the given definition.

Recommendation. Reporting on measurable characteristics (or metrics) attributed to primary forests conditions rather than on a broad definition left to country interpretation would improve the comparability of reported data at the global level and its use for decision making. Intact Forests Landscapes (IFLs) represent a good practical attempt to measure some of the related characteristics (lack of fragmentation in large tracks of forests) that exist in many primary forests. Although IFL mapping criteria excludes all burned areas regardless of their origin, human or natural, and their 500 km2 threshold was a subjective mapping criteria decision based on the best knowledge at the time, it provides an estimation of where large areas of unfragmented core habitat free of visual human impact exist, a forest characteristic that exists within primary forests as defined by FAO.

Because of the different nature and characteristics of the many biomes on Earth and the forest ecosystems within them, criteria to measure some primary forest’s characteristics might need to be adjusted to biome or appropriate scales.

Resources. Any reporting mechanism must acknowledge the differences among the countries’ financial resources to conduct forests estimations and inventories. Reporting on agreed primary forests characteristics could adopt a “tier approach”, where the accuracy of the data increases as we go down in the defined tiers. This would allow countries with fewer financial resources to report comparable numbers to countries with more financial resources.

Tiers could be defined for as many primary forest characteristics as are agreed. In the case of estimating unfragmented forest area, the following tier approach could be modeled:

1. Tier one – gross estimations as defined by IFLs or other mapping criteria identified for remote sensing analysis and using imaginary that is currently readily available and free.
2. Tier two – estimations of unfragmented forest area based on remote sensing analysis (tier one) and ground inventory data.
3. Tier three – precise estimations that combine inventory information with high-resolution remote sensing data and/or airborne data (lidar, hyperspectral, camera, etc.) that might not be freely available and might require more advanced processing and computing technology.

In conclusion, countries could report on acres of forest presenting each of the quantifiable and measurable characteristics associated to primary forests (unfragmented forests, undisturbed forests, etc), perhaps tailored to a biome scale, rather than total acres of primary forests using a general definition subject to country interpretation and political drivers.

1. The criteria “no clearly visible indications of human activities…” appearing in the definition is important and adequate when considering the use of Earth Observation data to assess or map ‘primary forests’ (or proxies of primary forests). Indeed remote-sensing based approaches can allow to detect and map disturbances in the forest cover but very old or small-scale disturbances may not be ‘visible’ from such data. Historical assessments of forest cover disturbances can be based on remote sensing time series but are limited by the availability and characteristics (e.g. spatial resolution and temporal coverage) of the satellite data. Currently, for the tropical regions adequate Satellite imagery (Landsat) is not available before the year 1982 for South-America (mostly Brazil) and much later for other tropical countries (the first valid image acquisitions are often not available before 2000 in Congo-Gabon and the Gulf of Guinea). Disturbances due to human activities or natural processes that occurred before the first available images cannot be mapped in regions like the tropics where no other historical wall to wall information is available.

Consequently, we suggest the following operational definition of primary forests that can be consistent with the available historical observation data:

“ Naturally regenerated forest of native tree species, where there are no clearly visible indications of human disturbances in the last 20 years or during the period of existing observation data” similarly to the initial definition of primary forest used by FAO (“not recently disturbed forest”).

3. We have developed an approach to map “undisturbed tropical moist forests” (TMF) that can be considered as an operational proxy to primary forests in the tropical moist domain. The approach is based on the detection of tree cover disturbances visible with Landsat satellite imagery over the full archive available (from Google Earth Engine). We consider a forest as undisturbed when no disturbances are detected over the full period of available historical imagery (varying from 10 to 30 years duration according to the region).

An expert-based system allows processing the full Landsat archive data from 1982 (c. 1 250 000 scenes in total for the tropics). The approach allows detecting tree cover disturbances that are visible in 0.09 ha size pixels - including disturbances from selective logging and fires that can be visible only during a short period -, and to map remaining moist forests without any visible sign of disturbances during the available observation period.  An annual change dataset is also provided depicting the spatial extents of TMF and disturbances for each year.

4. Suggestions to improve the reporting on primary forest area and its changes in humid tropical regions:

• We would need more information on the spatial distribution of historical disturbances. The large geographical and temporal unevenness of the Landsat archive prevents robust monitoring of disturbances before the year 2000 in some countries and consequently consistent monitoring among countries.  However, consistent monitoring is possible during the last 20 years over the full tropical belt.  Expert knowledge could complement the RS-derived maps when historical data are missing, to possibly exclude the forests that have been falsely identified as undisturbed based on ancillary historical data.
• Finer spatial resolution data are needed to capture smaller disturbances (e.g. removal of small single trees). Sentinel 2 data (0.01 ha size pixel) will significantly improve the detection of disturbances but such data exist only since the year 2016 and operational products are not yet existing on the continental/global scale.

5. FAO can help the countries by collecting and providing them access to the most relevant information, in particular, access to historical satellite imagery or existing products (maps of undisturbed forests) and by giving them support for using this information (i) technically, and (ii) by providing some guidelines to ensure consistency among countries.

I suggest using the Buchwald hierarchical terminology in Europe which would make al discussion about primary forest more relevant to the European continent.

A EU member states could report also through the Forest Information System for Europe.

The European countries monitoring data should also be integrated into the regular State of Europe's Forest (SOEF) reports. However, the definition must be standardised (eg. SOEF reports on undisturbed forest, which is a very vague term).

The reports must also include changes resulted either by natural or by human disturbance. The main purpose of reporting in Europe at least is to help strengthening the protection of the remaining few primary / old-growth forests (see old-growth forest strategy here).

Dear Team, 

Congratulations on tackling this difficult issue. I'm thrilled to see it on the docket as an important topic for FAO, and I am very appreciative of the opportunity to read the paper and respond.

1. The current primary forest definition is not adequate for North America if we wish for the variable to be comparable in a globally meaningful way. The definition is vague without discreet measurable parameters for various biomes, leaving it largely up to interpretation of each of the correspondents to locally define the variable. While that is "fine," it means that data point is not useful at the global scale, which is the purpose of the FRA data, in my opinion. In particular, I have some of the following concerns: a) The use of the word "natural" allows for a wide range of "degrees of naturalness" to be included in the primary forest category. For example, are forests that have grown over aztec ruins considered natural? Are they Primary or Secondary? Young forests can show natural forest dynamics, natural tree species composition, and natural age structures.  b) It seems the primary concern of FAO is commercial logging operations or other commercial use (as is evidenced by  the use of the terminology "no human intervention EXCEPT native people living native lifestyles"). How far back do we go to determine who is "native" or "indigenous" to an area, and how large can their disturbance for "traditional use" be before it becomes large enough to be considered human intervention? For example, in the United States, native Americans used fire broadly to manage forests - and to eliminate them - would that have been primary forest, still?  c) if we use the approach of remotely sensed data to create a metric representing "primary" forest, I'm still not exactly sure what it is we are measuring. Are we measuring ecological function? Because some "primary" forests are likely less biodiverse or less beneficial to humans/wildlife than well-managed secondary forests. Are we measuring human footprint? Because if so, native and indigenous populations ought to be included. Are we measuring growth stage or structural complexity or species composition? Because those things are not meaningful on a global scale. If remotely sensed data shows "greening" and "heights", what about in areas where the canopy is preserved and there is an understory that appears structurally mature, but it consists of nonnative species and/or planted agricultural crops?

2. Yes. I do not understand why there isn't some space given to the "WHY WE WANT THIS" question. There are lots of discussions of who has said it's important and what definitions various groups have adopted, but not a whole lot of "here is the question we are asking and why we are asking it."  Also, I have yet to see a good explanation of why human impacts are measured UNLESS it is native populations. Who cares if the disturbance is commercial or local if the impact is the same?  What if it's commercial exploitation by indigenous peoples? I don't mean to be obtuse, but I do not understand this exemption of "native people." People are people.  Perhaps it could be reworded to exclude particular USES by ANY people - e.g., not including low-impact uses like gathering pinecones for decorative purposes or gathering firewood for local use.  b) in the section of ecological characteristics, line 208, there's discussion of native species composition and natural levels of biodiversity. How native? What level of naturalization is necessary before something is native? At what point is something considered naturalized included in the "nativity" of the forest environment? Is there some scale or percentage of naturalness that a forest need meet before it meets the "natural level of biodiversity" and what is the baseline by which that is measured? When considering "biodiversity", we find that oftentimes disturbed forests are more biodiverse than undisturbed forests - so, not all biodiversity is necessarily desireable biodiversity. To what time period to we refer to determine what level of biodiversity is optimal?  

The source for US NATIONAL REPORT statistics is NOT Alvarez et al. Please correct.

3. The US uses the protected area database IUCN categories 1-5 as well as national parks, interior Alaska, wilderness areas, and other roadless forests.

4. We need a discreet understand of what the information is to be used for - what is the purpose of knowing the area of "primary" forest and how is it beneficial to the global community? Is the goal to re-establish or maintain some specific area of "primary" forest, and why? Someone define the question and the reason for the question, please.  I think that most likely the idea of primary forest is best addressed at the biome level rather than the global level in order to be meaningful.

5. Countries need very discreet, measurable characteristics in order to provide something useful to the environmental community, as well as a clear understanding of why the variable is important and how it will be used.

Thank you, and here's to a productive meeting in March.

Sonja Oswalt

Dear members of the FRA Forum,

Thank you to those that have already posted their feedback in the early stages of the consultation process. The contributions so far have provided valuable insights into the different methods used to measure primary forest cover (e.g. Landsat and aerial imagery; calculating tree densities and tree species cover; excluding areas around human impact areas) as well as methodological changes required to improve reporting (e.g. Harmonizing datasets and reporting rules; ensuring all forest areas are initially assessed). The current definition of primary forest generally appears to be well accepted by those who have contributed feedback, although issues around non-native forests being defined as primary forest is seen as an important consideration.

Also, the comments about the draft background paper have been very useful. The need for clarification about on ground forest condition assessment, primary forest detection methods and increasing the papers readability have been suggested.

Many thanks to those who have contributed so far. We welcome further inputs and reactions, as well as encouraging future contributors to refer as much as possible to the four guiding questions in the topic note.

Kind regards,

Patrick Norman

Griffith University

1. FAO definition of forest is good for me as an expert, but it is different my country definition and if possible the definition must the same as a world to compare our primary data of forest at worldwide.

2. It is good to add some literatures of primary forest rich area to acknowledge some countries

3. Use the newest and clear Land sat if possible

4. Data collection and forest resource inventories must start at true and reflected area and no need of any calculation to replace the forest left on other area

5. Cross checking and financing them

English translation below

De mon côté je suggère que la FAO puisse revoir la définition de la forêt. Avec l inventaire forestier national réalisé en République du Congo avec l appui de la FAO la forêt avec 0,5ha. 10% du couvert d arbustes et les arbres devraient atteindre 5metre d hauteur... Mais avec le dérèglement climatique et avec le processus REDD+ et le crédit carbone beaucoup des pays définissent leur forêt avec 3m d hauteur d arbre et 30% du couvert et la superficie de 0,5ha. Car les arbres ou arbustes de 3metre séquestre le carbone. Donc une bonne réflexion reste primordiale surtout de ce qui est aussi une forêt primaire.

Brice Dzatini , point focal FRA 2020 République du Congo

Personally, I suggest that FAO could review the definition of the forest. With the national forest inventory carried out in the Republic of Congo with the support of FAO, the forest should be of 0.5ha, 10% bush cover and trees should reach 5 meters high.

But with climate change and the REDD+ process and carbon credit, many countries are defining their forest with trees of 3m height and 30% of the cover and an area of 0.5ha.

Indeed trees or bushes of 3 meters capture carbon. So a good reflection remains essential especially for what is also a primary forest.

Brice Dzatini , FRA 2020 Focal Point Republic of Congo