https://orcid.org/0000-0002-4561-014X
Figures
Abstract
The links between road expansion and the decrease in ecosystem services in the Amazon region are widely acknowledged. The extraction of Non-Timber Forest Products (NTFPs) is considered a more sustainable livelihood alternative, although its profitability for local people is coupled to the presence of roads and other infrastructure. This study researched the roles that roads and other infrastructure play in the collection, storage, processing, transport and selling of Brazil nut (Bertholletia excelsa) and açai (Euterpe spp.), and its indirect effects on forest conservation in three neighboring research-sites in Brazil, Bolivia and Peru, in the southwestern Amazon. Methodologically, trends of the collected volumes of NTFPs were estimated through non-exhaustive accounting of local records; the endowment of roads, other infrastructure and forest loss were measured via time-series analysis of remote sensing imagery from between 2010 and 2020 and ground-validation; and the interaction between both was elucidated via semi-structured interviews with local stakeholders and experts. The outcomes show differences across the three research-sites in the development of roads and other infrastructure, and in trends of NTFPs production and deforestation. In Brazil and Peru, roads expanded and forest areas and NTFPs production decreased, whereas in Bolivia NTFPs production increased but roads and forested areas remained stable. Trends in post-harvest infrastructure growth were uneven, increasing in Bolivia due to the açai boom, and decreasing in Peru and Brazil. All this suggests that retaining NTFPs production levels is possible without an increase in new roads and without a major increase in post-harvest infrastructure. Innovations and developments like refrigeration are nevertheless necessary. NTFPs extractivism is still key in the region, but its further promotion is not without challenges. Adequate institutional and market settings, strong extractivist organizations, promotion of less-known NTFPs, and a boost in post-production facilities for well-known NTFPs are advisable measures. This requires political will and adjustments to the economic make-up of the region.
Author summary
It is known that road expansion is associated with the degradation of the Amazon rainforest and the decline of services it provides. However, the extraction of Non-Timber Forest Products (NTFPs) is still a sustainable livelihood option for locals, and their profitability often depends on roads and associated infrastructure. This study explored how roads impact the collection, storage, process and selling of two key NTFPs, Brazil nut and açai, and their effects on forest conservation between 2010 and 2020 in the tri-border region shared by Brazil, Bolivia, and Peru. The results show that in Brazil and Peru, roads expanded and forest areas and NTFPs production declined, while in Bolivia NTFPs production increased but roads and forest areas remained stable. Also, post-harvest infrastructure augmented in Bolivia due to the açai boom, while decreasing in Peru and Brazil. This suggests that it is possible to maintain NTFP production levels without building new roads and infrastructure. Still, it is key to maintain and improve current facilities, but also to strengthen institutions, markets and the organization of extractivists, what in some extent depends on political will and the profile of the region’s economy.
Citation: Mathäss P, Callo-Concha D, Frör O (2025) Are more roads needed? NTFP extractivism and the infrastructure dilemma in the southwestern Amazon. PLOS Sustain Transform 4(6): e0000175. https://doi.org/10.1371/journal.pstr.0000175
Editor: Ricardo Aleixo Correia,, University of Turku: Turun Yliopisto, FINLAND
Received: April 30, 2024; Accepted: April 24, 2025; Published: June 23, 2025
Copyright: © 2025 Mathäss et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All relevant data are within the manuscript and its Supporting Information files.
Funding: This research was funded by German Federal Ministry of Education and Research (BMBF), that financed the project Process-based and Resilience-oriented management of Diversity Generates Sustainability (PRODIGY; https://prodigy-biotip.org/). The awarded grants corresponds to the numbers 01LC1824A to 01LC1824F. DCC and PM were financed by that grant; while OF is officially employed by the RPTU Kaiserslautern-Landau. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
1. Introduction
1.1 Land-use challenges in the Amazon MAP region
It is well known that deforestation, land-use change and forest degradation are the major challenges threatening the Amazon’s provision of ecosystem services [1]. In the MAP region (acronym of the bordering states of Madre de Dios, Peru; Acre, Brazil and Pando, Bolivia), illegal logging, cattle ranching, agribusiness and mining activities [2] have intensified with rapid infrastructural development, triggered by the construction of the Interoceanic Highway [3,4].
Extractivist activities have transformed and intensified over many decades. The MAP region’s history is determined by two main features: its relative remoteness from capital cities, and its vast wealth in natural resources of high economic value, which led to successive waves of immigration and exploitation [2]. For instance, in the late 19th century, the high demand for rubber was satisfied from wild-growing tree species like Castilla ulei and Hevea brasiliensis growing in the region. Eventually, due to the introduction of rubber in Asia and the development of a synthetic substitute, rubber extractivism declined in importance [5]. Other economic activities followed similar cycles of expansion and contraction, like valuable timber logging, Brazil nut (Bertholletia excelsa) extraction, cattle ranching, gold mining, and in recent times, commercial farming [6,7].
1.2. Non-timber forest products extractivism
The extraction of Non-Timber Forest Products (NTFPs) such as resins, fruits, leaves and seeds, is a sustainable way of using natural resources. Evidence shows that forests where NTFPs extraction takes place are more biodiverse than forest plantations, more resilient against climatic fluctuations, and generate products and goods that support the people living nearby to meet their livelihood requirements and generate supplementary income [8,9].
In the MAP region, NTFPs extractivism is practiced customarily and has proven to be environment-friendly and sustainable, as resources are extracted selectively keeping in mind their replenishment. Such extractivism plays a key role for rural populations, often constituting the economic backbone of livelihoods and communities [10,11].
Brazil nut (Bertholletia excelsa) and açai berry (Euterpe spp.) are two of the most important NTFPs in the MAP region. In the Manuripi Reserve in Bolivia, up to 80% of the rural population’s income is generated by Brazil nut extraction alone [5].
Brazil nut is produced by tall and wild-growing trees, that prosper scattered in forested areas. The species’ survival and production are sensitive to the forests’ ecological intactness and climatic fluctuations [12,13]. Harvest is between December and March, when the ripe hard-covered fruit falls and is collected and brought to local facilities, where the outer hardshell is manually removed and the nuts are pre-dried. Post processing occurs in large facilities, mostly in neighboring cities [14,15] (Fig 1A, 1B, 1C and 1D). Açai is a naturally growing palm tree, found mostly in flooded areas. The fruit (açai drupe) grows in panicles located at the top of the tree, such that harvesters must climb the tree to collect the fruit. Processing is semi-mechanized and must occur within a short time-span to prevent the degradation of the perishable product [16] (Fig 1E, 1F and 1G).
Pictures: A. Escobar, M. A. Albornoz, M. J. Villavicencio.
1.3. The infrastructure challenge
In the three research-sites of the MAP region, the road network and other infrastructure are expanding, among other reasons for the collection, transport, processing, storage, marketing and export of NTFPs [17]. In 2011, the Interoceanic Highway was constructed to connect ports on the Atlantic and Pacific oceans and, crossing the MAP region, to enhance the economic integration and development of the region by improving its competitiveness in global markets [18].
However, there is evidence that road construction in the Amazon’s forested areas accelerates immigration, land-use change, deforestation, and land and ecosystem degradation [19–22]. For instance, new roads can be built officially by governments, but also unofficially by loggers who abandon them after removing hardwoods, and also by ranchers or farmers that may settle there permanently [20,23]. This process often follows the “fishbone” pattern, by which secondary roads are built perpendicular to primary roads, with the eventual emergence of tertiary roads [24]. Land use is directly related to accessibility: lands closer to roads and markets are more valuable, and therefore more profitable activities are pursued on them, whereas less profitable practices, such as NTFPs extractivism, are more common in remote areas [20,25].
Thus, although improved infrastructure can increase the profitability of NTFPs production, it intensifies the competition for land and activities associated with deforestation and ecosystem degradation, on which NTFPs production ultimately depends [26]. This balance needs to be carefully monitored.
Hence, this study analyzes the cases of Brazil nut and açai in the MAP region, by (i) estimating the endowment of roads and NTFPs-related infrastructure in the three research-sites; (ii) determining how road network expansion, deforestation and production volumes of NTFPs evolved between 2010 and 2020; and thereafter, (iii) analyzing the role that infrastructure plays in NTFPs extractivism, and the measures that could strengthen its sustainability.
2. Materials and methods
2.1. The research sites
The MAP region is populated by about 1,2 million inhabitants and extends over approximately 310 000km² [27–29]. The three research-sites share a similar biophysical environment and experienced the same historical boom and bust cycles, yet in more recent times have diverged greatly in respect to their distinctive administrative regimes, economic profiles and infrastructure [2,7,25].
The criteria for the selection of research-sites included the presence of land-use change, a major road, and a neighboring natural reserve. These were considered to roughly define equivalent polygons in each country that comprise areas with land-use intensities near zero, whereas the areas near roads (Interoceanic highway for Brazil and Peru and Route 11 for Bolivia), including settlements and agricultural lands, were considered of high land use intensity (Fig 2).
Sources: Esri Terrain with Labels. https://www.arcgis.com/home/item.html?id=2ef1306b93c9459ca7c7b4f872c070b9, terms of use https://www.esri.com/en-us/legal/terms/full-master-agreement, and Open Street Map data from Geofabrik: https://download.geofabrik.de/south-america.html), https://www.openstreetmap.org/copyright/en; RAISG (2020).
2.2. Analytical framework
This study used mixed methods. Successively, theoretical, empirical and observational data were combined to set up and validate a comprehensive understanding of the NTFP extractivism and infrastructure complex, i.e., (i) literature review of NTFP (Brazil nut and Açai) extractivism; (ii) quantitative assessment of key proxies, i.e., forest cover loss, road network expansion, and annual production volumes; and (iii) verification of findings via interviews with relevant stakeholders and on-site validation (Fig 3).
2.3. NTFPs extractivism
A literature review and the analysis of secondary data, were implemented to frame the historical background of NTFP, its current institutional setting, the identification of key stakeholders, and the characterization of value chains.
2.4. Proxies of NTFPs extractivism
2.4.1. Forest cover loss.
Forest cover and deforestation data was obtained from the University of Maryland’s “Global Forest Change” project, provided via global Landsat imagery as gridded raster files. The following datasets were downloaded: (i) Tree cover in the year 2000, including all vegetation over 5m height encoded as a percentage (0–100) per output grid cell; and (ii) yearly gross forest cover loss over the period 2000–2019 [30].
The criterion of forest adopted in this study is any area with a tree cover above 50% [31]. The “yearly forest cover” datasets have a spatial resolution of 28m per pixel, which was used to calculate the corresponding deforested area in km² based on pixel counts.
2.4.2. Road network expansion.
To estimate the road network expansion between 2010 and 2020, we required 30 000km² of orthorectified 5-band RapidEye imagery with a spatial resolution of 5m per pixel, covering the entirety of each research-site at two points in time. This was provided by the company Planet [32].
Mosaicking. From the provided imagery (for 2010 and 2020), single tiles were selected manually according to the visibility of roads on them. 136 of these tiles were composed to cover the full extent of each research-site. When cloud-free tiles were unavailable, these were composed by merging preceding or subsequent images, after which we obtained low cloud cover rates between 0,03% and 1,3%.
Land cover classification. With each of the created satellite image composites, an interactive supervised classification was performed. Using pixel samples, a defined color reflectance pattern was assigned to each of the following five image classes: roads, agricultural areas, forests, water bodies and clouds. The software extrapolated such patterns to surfaces of similar reflectance. This process was manually refined and optimized for each mosaic to achieve the maximum accuracy that this method allows. The resulting area covered by roads was transformed into a percentage of the total area for each research-site, to allow a comparison among them.
Shortcomings. This method is not exhaustive and some noise/inaccuracies can remain due to misclassification of surfaces by similar reflectance, e.g., some images of vegetation-free areas in the dry season can be classified as roads or roads crossing densely tree-covered areas could potentially be ‘hidden’ by canopy. Thus, the method might underestimate increases in road expansion in forested areas compared to those in areas without canopy. Still, we contend that the obtained results are sufficient to approximately quantify and compare the extent and expansion of road networks.
The Esri software ArcGIS 10.6 was used for mapping, geoprocessing, and geospatial analysis.
2.4.3. Annual production volumes of NTFPs.
The statistics on the production volumes of NTFPs in the three research-sites should not be assumed as absolute quantities, as recording systems vary by country and are often incomplete. Hence our strategy, for which we assume that the data is indeed representative, detected and compared changes and trends over time.
In the Brazilian research-site, the annual production volumes of NTFPs at the municipality level are regularly published by the Brazilian Institute of Geography and Statistics [33]. The overlaying of our research-site with the municipality of Brasiléia allowed us to use this data directly.
In the Bolivian research-site, the information on goods produced in rural areas is administered by the Authority for Social Control and Inspection of Forests and Land (ABT). We requested data for the municipality of Filadelfia, which contains our research-site. The available data covered Brazil nut volumes extracted from 2013 until 2020 [34]. The commercial exploitation of açai in our research-site began only around 2015, and is largely concentrated at two processing plants in Petronila and Villa Florida. Our data is sourced from the business plan of the processing plant in Petronila [35], the repository of WWF in Bolivia [36], and records from the Centre for Research and Promotion of Peasantry [37].
In the Peruvian research-site, permission to extract NTFPs is assigned via concessions issued by the National State Service of Protected Areas and the Regional Forestry and Wildlife Management office in Madre de Dios. Thus, production data was gathered from reports of concession holders [38,39]. Only concessions with complete data from 2010 until 2020 were considered, i.e., 15 out of 21. In Peru, most of the Brazil nut production data represents unshelled nuts, so we corrected the data by a factor of 0,5 as the shell makes up 50% of the fruit’s weight [40]. The reported volumes were summed up for each year to obtain indicative production trends. No data was available for açai, which in Peru is only occasionally consumed and traded locally by householders.
2.5. Verification of findings
Semi-structured interviews with 42 experts and local stakeholders of the NTFP sector were conducted between October and December 2020: 12 in Brazil, 18 in Peru and 12 in Bolivia. In each site, the interviewees represented four groups: (i) extractivists and concession holders; (ii) processing companies, associations and cooperatives; (iii) governmental institutions; and (iv) researchers and non-governmental institutions (details and coding in S1 Appendix, and on content in S5 Appendix).
A set of questions was developed referring to the 10-year period coincident with the gathered data. The open and multiple-choice questions were structured in four sections: (i) Challenges in extractivism, (ii) Production volumes and trade, (iii) Existing infrastructure for storing, processing and export; and (iv) Perspectives of extractivism. The questions were translated into Spanish and Portuguese and field-tested (see S2 Appendix). Interviews were conducted via video- and phone-calls, or in person with the support of local assistants. The identity of the interviewees was safeguarded and coded for further use. The anonymizing procedure and interview format are found in S1 and S2 Appendices.
The existing NTFP-related infrastructure, including collection sites, transport routes, points of trade, and processing facilities, were identified via literature and online research, requests to government entities and research institutions, and during the interviews. Key elements of the identified infrastructure were visited, georeferenced and/or photographed, and thus validated by local assistants. Road networks and much of the physical infrastructure were drawn from OpenStreetMap and RAISG databases [41,42].
The field research took place in the first year of the COVID-19 pandemic, which caused much of the work to be implemented remotely. Still, five local assistants in the three sites supported field data collection, which included requesting data from local institutions, conducting and facilitating interviews with key stakeholders, and performing on-site geo-validations.
3. Results
3.1. NTFPs production trends
Regarding Brazil nut, in the municipality of Filadelfia, Bolivia, volumes harvested show some fluctuation, but an overall increasing trend and a late stabilization, from 2019 onwards. In Brasiléia, Brazil, a downward trend is observed over the period 2010–2019, with a peak in 2012 and a low in 2017. In the study area in Madre de Dios, Peru, similarly, a downward but fluctuating trend in harvested volumes is observed (see Fig 4).
Volumes for Peru are not exhaustive. Data sources: ABT Pando (2020); GRFFS (2020); IBGE (2020); SERNANP (2020).
As already pointed out, the recorded volumes of Brazil nut are not intercomparable: records are not exhaustive, the research-sites are of different sizes, and there are gaps in the datasets. Hence, the values are rather indicative of the production trends in each of the sites. Besides the ascending trend in Bolivia, a descending trend was observed in Brazil and Peru. In Brazil and Peru, a maximum value was registered in the year 2012 (for which no data was available for Bolivia). Similarly, the production volumes in Bolivia and Brazil fell to a minimum in 2017 (not evident in Peru, also due to the lack of data), which coincides with records of a heavy drought that hit the region [43].
In the case of açai, there is a consistent increase in its production in Bolivia, which has grown 20 times with the establishment of processing plants in the years 2015–2017 [36]. Contrarily, in Brazil there was a steady decline in açai production until 2016, when it appears to have reached a stable plateau [33]. In Peru, the commercial production of açai is nonexistent (Fig 5) (Time series’ details in S3 Appendix).
Data sources: CIPCA (2020); IBGE (2020); WWF Bolivia (2020).
3.2. Land cover and road network expansion
In the Brazilian site there is a continuous decline in forest cover, of roughly 13 percentage points (from 75% to 62% forest cover) in ten years, while areas covered by roads increased by 0,11 percentage points (from 0,92% to 1,03%). In Bolivia, the forest cover decreased by less than 1 percentage point (from 97,7% to 97,1%), and counterintuitively, the road cover also declined by about 0,01 percentage points (from 0,19% to 0,18%), although such decline may be due to a methodological limitation. In Peru, the decline in forest cover is continuous and of 9 percentage points from 90% in 2010 to 81% in 2019, and inversely, the road cover grew by 0,13 percentage points from 0,71% to 0,84%. Both the forest cover and road cover differ notably among the three sites, and an ordering is clearly identifiable: Bolivia shows the least deforestation, whereas Peru followed by Brazil are the most deforested with the most new road construction (Time series details in S3 Appendix) (Fig 6).
Forest cover data: Own analysis based on data provided by Hansen/UMD/Google/USGS/NASA (2020). Road cover data: Own analysis based on Image © 2020 Planet Labs PBC.
3.3. NTFPs value chains
The Brazil nut value chain in Brazil is straightforward. After being collected by extractivists, it is transported to storage sites by cattle or motorbike, then traded by intermediaries to larger cooperative- or private-owned storage sheds, to be taken to processing factories in larger volumes. There, the sanding, classification, shelling, and vacuum packaging takes place, for the nuts to finally be sold in local markets or exported. For açai, the value chain requires processing within 48h after harvest and a subsequent continuous cold chain. Bagged in the field, it is directly transported to processing plants in neighboring cities like Brasiléia, Xapuri or Assis Brasil, or even to Rio Branco, the capital city. At times, cooperatives themselves collect the fruits from individual gatherers. In factories, the fruit is mashed, washed, heated, centrifuged, packed, and refrigerated for distribution and selling (Pers. Comm. BrCo1, BrEx1 and BrEx5, BrGov2 and BrRes2).
Acre’s largest actor in the processing and trade of NTFPs is the Central Cooperative of Extractive Commercialization of Acre (COOPERACRE, in Portuguese), which is based in Rio Branco. They target mainly Brazil nut, but also fruit pulp (including açai), rubber and copaiba oil [44]. Most of the processed Brazil nut is exported, whereas the açai is entirely consumed by local markets (Pers. Comm. BrCo1).
In Bolivia, Brazil nut is collected either by families or the so-called barraqueros, wealthier individuals owning/administering larger Brazil nut-endowed forest areas, who hire seasonal workers for the nut collection. Thus, the value chains may differ. The nuts gathered by families are transported to a payol (storage shed) by motorbike, where they are dried, classified and bagged in barricas -standardized deposits- of 66 kg each. Depending on the volume, the bags are either transported to a larger private or community accumulation shed, or sold directly to intermediaries who bring them by car to Cobija or by boat to Riberalta or El Sena (both in the neighboring department of Beni), for the nuts’ final processing. In the case of the barraqueros, the nuts are often taken directly to the processing companies. Notably, around 95% of the Brazil nut produced in Bolivia is exported internationally. In the case of açai, the 48h processing time window together with limited processing capabilities shortens the value chain: after collection, the fruits are transported directly to a processing facility by motorbike, where they are processed and the pulp stored in a freezer, being regularly picked up by refrigerated vehicles to be taken to Cobija city by road. Açai is mostly sold locally but also to other Bolivian departments (Pers. Comm. BoEx1, BoEx2, BoEx3, BoEx4, BoCo1, BoGov1, BoRes1, BoRes3 and BoRes4).
In Peru, the Brazil nut value chain is simpler, with a key distinction that inside the Tambopata reserve the transportation of the gathered nuts to the payoles is done by foot, as the use of motorbikes is forbidden. The next steps include the transportation of barricas to trading points along rivers or roads where they are sold to intermediaries, associations, or processing companies. The nuts are then further transported to larger storage centers or processing facilities in Puerto Maldonado. Since the construction of the Interoceanic Highway, the value chain has simplified even more, as some extractivists bring their nuts to the roadsides without prior drying or even directly to the larger processing facilities in Puerto Maldonado. In Peru, açai is neither produced nor consumed significantly (Pers. Comm. PeEx1, PeEx2, PeEx3, PeEx5, PeEx6, PeCo1, PeCo2, PeGov2, PeCo4, PeCo5, PeGov3 and PeRes3).
3.4. NTFPs: Existing infrastructure
In the Brazilian research-site, despite an extensive road network, respondents describe the access conditions as precarious and as a major limiting factor for NTFPs trade. The biggest Brazil nut processor is COOPERACRE, a local cooperative that runs storage sheds across the state, including in the cities of Assis Brasil, Epitaciolândia and Xapuri close to the research-site. However, there are other smaller facilities managed by local organizations in Assis Brasil, Brasiléia and Xapuri [45]. In the case of açai, there is a COOPERACRE processing plant in Brasiléia (Pers. Comm. BrGov2).
In the Bolivian research-site, there is only one partly paved road (Ruta Nacional 16), and hence, rivers remain important transport routes. About forty barracas (storage sheds) exist including privately-, community- and company-owned ones of different sizes (Pers. Comm. BoGov1). Five processing plants were reported in Cobija city, including Tahuamanu S.A., the largest, with a processing capacity of 10 500 t/year [46]. Commercial harvesting of açai takes place in proximity to the existing processing facilities of Petronila and Villa Florida, but in limited capacities, all below 10 t/year [37].
In the Peruvian research-site, the transport of produce is via footpaths and rivers. After accumulation and pre-drying in local storage sheds, Brazil nut is transported and sold to intermediaries at trading points, and later brought to one of over 10 processing facilities in Puerto Maldonado city. The majority are privately-owned, whereas a few belong to cooperatives or community organizations [38,39].
3.5. NTFPs production and infrastructure-related limitations
Key stakeholders were asked about the role and evolution of infrastructure in NTFPs production over the past 10 years (ca. 2010–2020). Their responses are only indicative, as not all interviewees responded evenly to all the questions (details in S4 Appendix).
When asked about the influence of external factors on Brazil nut production, changes in the climate, particularly drought, was the most pressing factor mentioned for all three countries, especially Bolivia. Brazil nut’s volatile price and its decreasing yields were also underlined as relevant (Fig 7A). Regarding açai, to a considerably lower degree, changes in climate, decrease of yields, and overall, the lack of processing plants, were highlighted as limiting factors (Fig 7B).
A. Brazil nut and B. Açai between 2010 and 2020.
Most of the Brazilian and Peruvian stakeholders believed that the overall conditions for Brazil nut collection had improved, while Bolivian stakeholders were more restrained (Fig 8). However, in all three countries, to different degrees, our respondents thought that production had decreased. Concerning açai (exclusive to Bolivia and Brazil), the stakeholders of both countries asserted that some limited changes had occurred in the conditions for extractivism; Bolivians reported considerable improvements in production (almost 70%), while Brazilians stated poor gains (Fig 8).
When asked to focus on the specific importance of roads and infrastructure for NTFPs production, the stakeholders’ responses prioritized roads’ improvement over the construction of new roads. The construction of more storage and processing facilities was frequently mentioned, more so in Bolivia than in Brazil and Peru. When asked how the NTFPs sector could be improved, stakeholders alluded to their industrialization, e.g., to produce Brazil nut oil or milk, and freeze-dried açai (Fig 9).
4. Discussion
4.1. NTFPs production challenges
In the Brazilian research-site, the decline of Brazil nut production is due to several factors: climate-derived yield fluctuations, market-induced price volatility and changes in land use, among the most important [47]. Our evidence on land-use change is conclusive: 13% of forest area reduction in ten years is substantial, implying a reduction in productive land, change in the trees’ surrounding ecosystem, and competition by other more profitable land uses. Açai production in Brazil follows a different trend: it descended steadily until 2017 when drought hit Brazil nut production [43], and rose thereafter, likely as a householders’ measure to compensate their deficit in income. Still, production volumes are low and non-competitive against other income sources. Furthermore, differently to other Brazilian states where açai is cultivated, in Acre only wild açai is collected from well-conserved forests which are decreasing in the region (Pers. Comm. BrCo2).
In the Bolivian research-site, the production of Brazil nut and açai has generally increased [34–37]. A basis of this growth lies in the consolidated extractivist tradition ingrained in the population of the research-site, as well as the relatively stable demand for Brazil nut by well-established processors based in the neighboring Cobija city. Concerning açai, the low volume but fast growth is a result of its rising demand in national markets [48] and the well-preserved conditions of local forests and swamps where the palm prospers. To date, it was repeatedly mentioned, the exploitation of existing açai stands remains minimal. Interestingly, these insights contrast with observations in the other two research-sites, that variations in yields are caused by climate and international price fluctuations.
In the Peruvian research-site, Brazil nut production volumes are low and tended to decline over the ten-year period, while other economic activities have emerged and made extractivism less attractive by the ostensible differences in gains. This has occurred despite the improvements in accessibility (expanded road network), and perhaps due to it: for there has been a proportional increase in deforestation. Açai and several other NTFPs have the potential to become commercially attractive in the future, but are unlikely to become flagship products due to deforestation and the prominence of other economic activities [48].
In general, NTFPs production has grown in Bolivia, while in Brazil and Peru it has reached a steady plateau shadowed by other economic activities. Still, livelihoods diversification is widely encouraged as a strategy to reduce the dependency on Brazil nut, and to strengthen the resilience of householders.
4.2. Roads and other infrastructure: How much do they help?
In the Brazilian research-site, despite its extensive road network, NTFPs extractivists complain about the poor conditions of roads. In fact, openings for new roads are made by loggers to establish pastures for cattle ranching, which explains the poor state and lack of maintenance of such roads [49](Pers. Comm. BrEx1, BrEx3, BrEx4, BrEx5 and BrEx6). This poor condition of roads is widely held to be the major limiting factor for NTFPs extractivism, in particular for açai, as the fruits can only be processed within a 48h time-span [50] (Pers. Comm. BrGov2 and BrRes2). Regrettably, land-use change has become increasingly politically contingent. For example, during his presidential term, Mr. Jair Bolsonaro openly expressed a tolerance for road openings [51]. Regarding other infrastructure, and in contrast to the extensive road network, the research-site has few and smaller storage and processing facilities, with the larger ones located in Rio Branco city, about 250km away.
In our Bolivian research-site, Brazil nut transport largely depends on the use of rivers adjacent to the non-paved Ruta Nacional 16 (Fig 2) (Pers. Comm. BoGov1 and BoRes4). Most experts and stakeholders recognize the road network as “sufficient” but complain of its poor maintenance, and some suggest that its upgrading would boost the local economy, while others warn that it could lead to overexploitation and environmental harm [19,47,52] (Pers. Comm. BoRes1, BoRes2, BoRes3 and BoGov1). The opening of new roads is anyway forbidden in the Manuripi Reserve. This study’s observed decline in road cover, we can add, is likely the result of methodological limitation: the tree canopy “grew”, covering and thus impairing the detection of roads, as can be observed by comparing two images in the elapsed time.
Regarding post-harvest infrastructure, Brazil nut storage sheds abound but processing facilities are only found in Cobija city, between 70 and 150km from the fringes of our research-site. In the case of açai, local infrastructure swiftly developed following its growing demand, with two processing facilities already set-up and another being built [48,53]. Nevertheless, current refrigerating capacities, processing equipment, facilities and refrigerated transport appear insufficient, as demand and expectations grow (Pers. Comm. BoCo1, BoGov1, BoRes1, Bores2, BoRes3 and BoRes4).
In the Peruvian research-site, although the volume of Brazil nut collected has decreased, the accessibility by road increased, as confirmed by satellite imagery and stakeholders’ testimonies. On the one hand, this has minimized the need for storage and drying sheds and shortened the value chain, though quality losses have been reported due to poor pre-drying (Pers. Comm. PeCo2 and PeGov2). On the other hand, improved access due to road expansion has led to the flourishing of other economic activities like farming, ranching and mining, which often outcompete Brazil nut extractivism [26,25,47] (Pers. Comm. PeEx4. PeEx5, PeEx6, PeGov2, PeRes1 and PeRes3). Mining is especially damaging due to its environmental impact and its links to crime. The difficulties faced by NTFPs extractivists intensify when their concessions border with concessions for mining, farming and ranching (Pers. Comm. PeRes1 and PeRes3) (Fig 10). Wherever possible, the use of river remains a reliable transport option.
Sources: Esri World Imagery https://www.arcgis.com/home/item.html?id=10df2279f9684e4a9f6a7f08febac2a9 and Esri Terrain with Labels https://www.arcgis.com/home/item.html?id=2ef1306b93c9459ca7c7b4f872c070b9, terms of use: https://www.esri.com/en-us/legal/terms/full-master-agreement; Open Street Map from Geofabrik https://download.geofabrik.de/south-america.html) terms of use: https://www.openstreetmap.org/copyright/en; RAISG (2020), SERNANP (2020).
Our analyses confirmed that, of our research-sites, Brazil has the most extensive road network, followed by Peru and lastly, the least developed, Bolivia. The extent of the road network is demonstratively inversely proportional to the deforested areas. A recent household survey in the same three research-sites reaffirms this trend, and confirms the steady and fast expansion of road networks in Brazil [54]. Leaving aside other land uses like cattle ranching, it is clear that extensive road networks are not needed in the NTFPs sector, and their construction for that purpose should be prevented. Strategically-placed and well-maintained roads suffice for NTFPs collection and transport, reducing harm to ecosystems and communities [19,47,49]. Calculated improvements to other infrastructure appear promising, for instance, the strategic placing of Brazil nut storage facilities in Peru, the establishment of more açai processing plants and refrigerated storage along the Ruta 16 in Bolivia; and the promotion of riverine transport where required and possible.
Such measures, however, require reliable NTFP value chains and stable markets to secure their profitability (Pers. Comm. BoCo1, BoEx2, BoRes2, BoRes3, BoRes4, BrCo1, BrGov2, Br Res1, BrRes2, PeEx4, PeCo5, PeCo6, PeGov2, PeGov3, PeRes1 and PeRes3), and broader policies and measures to prevent deforestation and the harmful side-effects of other land uses (Pers. Comm. BoRes1, BrRes1, PeCo1, PeGov1 and PeRes1).
4.3. Is NTFPs extractivism still sustainable?
NTFPs production levels are uneven across the MAP region. In the Bolivian research-site, production is steady for Brazil nut and growing for açai, while in the Brazil and Peru sites, the production of NFTPs is on the decline. However, land-use change (deforestation) and follow-up competing land uses appear equally determinant, as confirmed in this study’s positive association between deforestation rate and road network expansion, as also reported in previous studies [19,47].
Roads are highly valued by rural householders for their many benefits. Our findings show that the existing road network is sufficient for the transport of NTFPs; indeed, it is excessive in Peru and Brazil. Stakeholders acknowledge this sufficiency and some are wary of the medium- and long-term effects of further road expansions. Road maintenance could by improved in many places.
Infrastructure availability and conditions vary by country and research-site. While processing infrastructure is growing in Bolivia under the açai boom, it is losing prominence in Brazil and Peru due to the relative loss in competitiveness of NTFP extractivism against other economic activities. In Brazil and Peru therefore, improvements in Brazil nut storage and processing may optimize but not boost current stands. On the contrary, investments in açai processing, cold-storage and transport appear quite economically rewarding [48], but only where forests endure and the extractivist tradition stands, i.e., in the Bolivian research-site.
The diversification, postprocessing infrastructure and industrialization of NTFPs are alluded to as possibilities to boost NTFPs production. Species like Majo (Oenocarpus bataua Mart), Motacu (Attalea phalerata Mart. ex Spreng) and Aguaje or Palma Real (Mauritia flexuosa L.f.)., are abundant and notably underutilized, e.g., [16]. The introduction of advanced conservation technologies, like freeze drying, could prevent spoilage and become a surrogate of cold chain for açai (Pers. Comm. BoRes2, Bores3 and BoRes4). The economy of scale for products like açai powder is however as yet unknown, e.g., market size, consumer acceptance. In the case of the more known and stable Brazil nut, the absence of value-added products -besides some modest snack industry products- is surprising: oil, flour, soap, milk and butter are all potential ones (Pers. Comm. BoRes3 and PeRes2). So far, such industries are nonexistent.
It is important to note that physical infrastructure alone will not increase the productivity and profitability of NTFPs. NTFPs extractivism requires supportive social and institutional infrastructure in light of other competing land uses. Such “social” infrastructure should be stable, to guarantee long-term actions and secure returns, but also multifaceted, e.g., by protecting gathering-lands, safeguarding associations of NTFPs extractivists, and securing stable prices, scouting for international markets, and promoting the conscious consumption of NTFPs [55]. The necessary policies and measures cannot be generalized and must be adapted to each region in accordance with its particularities, as demonstrated in this and previous studies [56].
The longevity of NTFPs extractivism requires the sustained engagement of rural populations. Although it has clear environmental benefits, it is currently unclear if younger generations will retain an interest in NTFPs extractivism as a livelihood, as incentives are already reported to have declined in Brazil and Peru (Pers. Comm. BrGov1, PeCo6, PeRes1 and PeRes3). This may relate not only to its economic profitability, but its social appeal and unattractiveness compared to other activities [52].
As for climate, its fluctuations, and especially droughts, are widely accused of affecting NTFP production (Fig 7), cyclical phenomena such as El Niño-Southern Oscillation add evidence to this [57]. However, the impacts of climate change are still not fully recognized and sometimes overlooked, despite the mounting examples of recent fires, smoke and dust impacts on peoples’ health, integrity of ecosystems and NTFP harvests [58,59]. The long-awaited payment for ecosystem services, via programs such as Reducing Emissions from Deforestation and Forest Degradation (REDD+), could potentially prop forest conservation and activities like illegal logging and mining, and alongside encourage NTFP extractivism. However, its implementation and effectiveness are still debated [60,61], and in all cases, its scope in relation to the challenge remains limited.
Finally, it is candid to acknowledge that improving the conditions for NTFPs extractivism necessarily entails interventions in forests. Despite the impacts being much lower than those of logging and cattle ranching, they should not be neglected; in protected areas and indigenous territories, for instance, commercial NTFPs extractivism should only be promoted, if at all, with caution and under strict conditions.
5. Conclusions and outlook
This study aimed to evaluate, for the period 2010–2020, the degree to which roads and infrastructure have evolved alongside the production of NTFPs in three country-sites of the MAP region. The three research-sites differ in their endowment of roads and other infrastructure, but also in the trends of NTFPs production and deforestation. In Brazil and Peru, the road network has expanded consistently, and associated with this, deforested areas have increased too. In Bolivia, on the contrary, NTFPs production has increased but the roads and the forested areas have remained stable. Concurrently, the development of post-harvest infrastructure is uneven: stable and tending to increase in Bolivia -due to the açai boom-, and fading in relevance in Peru and Brazil. This suggests that retaining NTFPs production levels is possible without an increase in new roads or a major increase in existing post-harvest infrastructure. Innovations and developments, like refrigeration, are nevertheless necessary.
The overarching reason for these differing trends are the diverging developmental paths of the respective countries. While Brazil’s ranching and Peru’s economic diversification have opened up economic opportunities and weakened NTFPs-related physical and social infrastructure, Bolivia’s attachment to NTFPs-gathering persists. In Bolivia, the absence of other alternatives, the entrenched traditions of its population, and the good stand of its forests all keep NTFPs-related activities profitable.
NTFPs extractivism still plays a determining role in the development of the MAP region, but its promotion has to be carefully thought through. Providing optimal institutional and market conditions, promoting extractivist organizations, stimulating the collection and utilization of less-known NTFPs, and the development of post-production facilities of well-known NTFPs, are certainly useful measures in the current situation. But equally important is to acknowledge the changing economic make-up of the region, and its diverse and changing priorities.
By the broad nature of this study, which covers the road and infrastructure networks for two NTFPs in three different countries, over a period of ten years, our outcomes should be treated cautiously if taken for extrapolation to other products and areas.
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