Madre De Dios Region Research Articles

Heavy metals in alluvial gold mine spoils in the peruvian amazon

Alluvial gold mining in the Peruvian Amazon has become a key driver of land degradation and deforestation. The associated release of mercury in the environment poses direct human health risks and is likely to engender cascading effects throughout local food chains. We carried out research in an alluvial gold mine concession in the Madre de Dios region to compare the degree of soil-borne pollution of heavy metals in areas where mining operations were abandoned more and less recently (1–5 and 6–8 years ago, respectively) with non-impacted old-growth forest areas. All heavy metals, were below permissible levels according to Peruvian and Canadian environmental quality standards. Mean As, Ba, Pb, Cu, Cr, Ni, V and Zn concentrations in impacted areas were 1.90 ± 1.51, 29.80 ± 22.87, 4.60 ± 2.55, 12.68 ± 8.13, 7.90 ± 3.98, 7.93 ± 3.89, 12.67 ± 6.62, and 26.65 ± 13.53 mg kg−1 dry matter (DM), respectively. Heavy metal concentrations were higher in non-impacted old growth forest soils than in mining spoils, and tended to increase with time since abandonment of mining operations. Hg was not detected in any of the sites. Low heavy metal concentrations in mine spoils might beexplained because of intense volatilization, reduced metal retention capacity due to the low clay and organic matter content, and leaching processes related with soil rinsing which is part of the mining operations combined with intense rainfall. Our findings suggest that heavy metal concentrations in mining spoils should not be considered to constrain forest restoration efforts or the development of similar land uses as in comparable non-impacted high forest soils.

Twenty years of land cover change in the southeastern Peruvian Amazon: implications for biodiversity conservation

The Amazonian ecosystems of Madre de Dios (MDD) region, considered Peru’s “capital of biodiversity” due to its impressive species richness, are threatened by the rapid expansion of infrastructure. The paving of the Interoceanic Highway in 2010 has brought rapid population growth and environmental degradation, threatening large-scale conservation efforts such as the Vilcabamba-Amboro Conservation Corridor (VACC). To quantify the impacts of development processes and to identify critical areas where further conservation efforts should be focused, we analyzed 20 years of land use and land cover (LULC) dynamics, drivers, and fragmentation patterns in MDD. We mapped LULC in 1993, 2003, and 2013 using Landsat imagery and modeled the proximate drivers of change related to deforestation, forest regrowth, gold mining, agriculture, and urban expansion in two time periods (1993–2003 and 2003–2013). We characterized habitat fragmentation patterns in four regional target areas. Our results show accelerated deforestation triggered by the road network spreading, mining and agriculture expansion, and population growth. LULC changes produced two contrasting spatial landscape patterns: numerous small forest fragments in the north due to agricultural expansion along the Interoceanic Highway and large continuous forest losses caused by gold mining expansion in the south. Current unplanned development in this region is threatening its outstanding biodiversity. We suggest that further conservation efforts should focus on strengthening the legal framework of the VACC, implementing a sustainable management plan for MDD, promoting agroforestry strategies along the Interoceanic Highway, and preserving smaller corridors for animal movement.

Treehoppers (Hemiptera: Aetalionidae and Membracidae) from Madre de Dios region, Peru

A list of treehoppers (Aetalionidae and Membracidae) is presented from Madre de Dios region at the southeastern Amazon basin in Peru. The treehopper specimens were collected as by-catch in a survey of the beetles in the Villa Carmen Biological Station and Los Amigos Biological Station. The list comprises 44 species, 31 genera, 16 tribes and 9 subfamilies. Ten genera are new records to Peru. The images of representative specimens of each identified species and genera are provided to facilitate the identification of the local treehopper fauna.

A spatial pattern analysis of forest loss in the Madre de Dios region, Peru

Over the past decades, the Peruvian Amazon has experienced a rapid change in forest cover due to the expansion of agriculture and extractive activities. This study uses spectral mixture analysis (SMA) in a cloud-computing platform to map forest loss within and outside indigenous territories, protected areas, mining concessions, and reforestation concessions within the Madre de Dios Region in Peru. The study area is focused on key areas of forest loss in the western part of the Tambopata National Reserve and surrounding the Malinowski River. Landsat 8 Operational Land Imager and Landsat 7 Enhanced Thematic Mapper Plus surface reflectance data spanning 2013–2018 were analyzed using cloud-based SMA to identify patterns of forest loss for each year. High-resolution Planet Dove (3m) and RapidEye (5m) imagery were used to validate the forest loss map and to identify the potential drivers of loss. Results show large areas of forest loss, especially within buffer zones of protected areas. Forest loss also appears in the Kotsimba Native Community within a 1 km buffer of the Malinowski River. In addition to gold mining, agriculture and pasture fields also appear to be major drivers of forest loss for our study period. This study also suggests that gold mining activity is potentially not restricted to the legal mining concession areas, with 49% of forest loss occurring outside the mining concessions. Overall accuracy obtained for the forest loss analysis was 96%. These results illustrate the applicability of a cloud-based platform not only for land use land cover change detection but also for accessing and processing large datasets; the importance of monitoring not only forest loss progression in the Madre de Dios, which has been increasing over the years, especially within buffer zones, but also its drivers; and reiterates the use of SMA as a reliable change detection classification approach.

Heightened levels and seasonal inversion of riverine suspended sediment in a tropical biodiversity hot spot due to artisanal gold mining

In recent years, rising gold prices have exacerbated the global proliferation of artisanal-scale gold mining (ASGM), with catastrophic consequences for human and ecological health. Much of this burgeoning industry has occurred in biodiversity hot spots, notably in the tropical forests of South America. While the loss of tropical forests and floodplains as a result of ASGM has been well characterized, ASGM impacts on riverine hydrological properties are less understood. Previous fieldwork on ASGM-affected and gully-eroded tropical streams and rivers has demonstrated that increases in suspended-sediment concentration (SSC) can substantially impact fish diversity and aquatic community structure, yet our understanding of the timing and scope of impacts of such increases is limited by the lack of long-term records of SSC. To address this challenge, we present a 34-y analysis of the direct effect of ASGM on 32 river reaches in the Madre de Dios region of Peru, which has been heavily impacted by ASGM since the 1980s. We evaluate spatial and temporal patterns of impacts using estimated SSC derived from Landsat satellite imagery. We find that 16 of 18 stretches of river impacted by ASGM show significant increasing trends in SSC (P < 0.05), while only 5 of 14 unaffected sites do so. Additionally, ASGM appears to reverse natural seasonal cycles of SSC, which may imperil aquatic species. Overall, our findings indicate that ASGM is fundamentally altering optical water quality dynamics of a critical tropical biodiversity hot spot and provide guidance for future regulation of these activities.

Mercury exposure, risk factors, and perceptions among women of childbearing age in an artisanal gold mining region of the Peruvian Amazon

Recent studies from the Madre de Dios region of Peru report elevated mercury exposure among the general population. Our objective was to assess mercury exposure, risk factors, risk perceptions, and knowledge among women of childbearing age, a population of concern due to risks to infant and fetal health. We collected hair samples and administered a survey among 200 women aged 18–49 years residing in Madre de Dios. Hair total mercury (THg) concentrations were analyzed in accordance with EPA Method 7473. Associations between exposures and potential risk factors were analyzed using generalized linear mixed models. Geometric mean hair THg concentration (±standard deviation) for all participants was 1.62 ± 2.54 μg/g (range: 0.01–30.12 μg/g), and 67 participants (33.5%) had concentrations above the 2.2 μg/g reference dose established by the World Health Organization (WHO). Higher exposure was significantly associated with higher fish consumption (p = 0.03) and less mercury knowledge (p < 0.0001), but not with age or educational attainment. Most participants (86.2%) expressed concern about mercury contamination, but few (26.2%) had knowledge of the health risks associated with exposure. Many residents consumed fish species previously found to have low mercury concentrations, but more than 25% of participants reported consuming fish species with high mercury concentrations. We did not observe cross-sectional differences in fish intake among women who were pregnant or breastfeeding at the time of data collection.

In urban, but not rural, areas of Madre de Dios, Peru, adoption of a Western diet is inversely associated with selenium intake

Road development has been a major driver of the transition from traditional to calorie-dense processed ‘Western’ diets in lower and middle-income countries. The paving of the Interoceanic Highway (IOH) facilitated rapid development to the Madre de Dios (MDD) region in the Peruvian Amazon. As traditional foods such as Brazil nuts and fish are known to be rich in the essential micronutrient selenium, people further along the nutrition transition to a Western diet may have lower selenium (Se) intake. To test this hypothesis, in 2014 the Investigacion de Migracion, Ambiente, y Salud (IMAS Study) (Migration, Environment, and Health Study) collected household surveys from 310 households in 46 communities along the IOH and nails for Se analysis from 418 adults. Principal component analysis of 25 commonly consumed food items identified a factor resembling Western diet, which was used to calculate household Western diet weighted sum factor scores (WSFS). WSFS means were interpolated into a 10 km buffer around the IOH using inverse distance weighting. Western diet adoption was higher in urban compared to rural areas (p < 0.0001), and geographic variation was observed between mining and agricultural areas. Mean nail Se was 730 ng/g, SD 198 ng/g (range: 200–1390 ng/g). Generalized estimating equation (GEE) models assessed the association between food consumption and nail Se. Household chicken consumption was positively associated with Se in rural areas only. Urban/rural status modified the effect of western diet adoption on nail Se, and Se was inversely associated with WSFS in urban areas only. Conclusion: In urban, but not rural, areas of Madre de Dios, Peru, adoption of a Western diet is inversely associated with selenium intake. As the essential micronutrient selenium is a vital part of antioxidant proteins, lower intake could compound the chronic health effects that may result from transition to a calorie-dense diet.

Brazil nut forest concessions in the Peruvian Amazon: success or failure?

In Peru, concessions for harvesting Brazil nuts (fruits of the Amazon tree Bertholletia excelsa) were launched in the Madre de Dios Department in 2000. This study analyses the extent to which the Brazil nut concession system (which covers about 1 million ha of closed canopy forest) has met its objective of providing a governance model for sustainable and equitable use. Primary and secondary information sources were used to analyse governance outcomes based on 10 indicators, and the performance of Brazil nut concessions in two contrasting land-use types in Madre de Dios were compared (within and outside protected areas). It was found that corresponding institutional arrangements have led, more than a decade later, to different socioeconomic, ecological and legal outcomes. Particularly outside protected areas, where the vast majority of the concessions are located, a paradoxical situation was found of ineffective over-regulation on paper but minimal intervention from state agencies; ineffective state monitoring and sanctions; poor law enforcement with excessive punitive measures; power imbalances in the value chain and illegal timber harvesting; the lack of a multiple forest-use framework; and overlapping, conflictual customary and regulatory governance. This paper argues that at present, the long-term sustainability of the Brazil nut concession system seems compromised. If the Brazil nut concession system is to enter into a new decade, this may only be possible by formally recognizing the multiplicity of land uses, implementing and validating sound silvicultural approaches, minimizing land use and management trade-offs in alignment with local aspirations, and establishing effective negotiation platforms with different productive sectors and government agencies.

Description of Walkeriella miraculosa, gen. n. et sp. n. from South-East Peru(Lepidoptera: Hepialoidea: Hepialidae).

Walkeriella miraculosa gen. n. et sp. n. (Lepidoptera: Hepialoidea: Hepialidae) is based on two specimens collected from rainforest southwest of Puerto Maldonado, Tambopata, Madre de Dios department, southeastern Peru. The distinct genitalia and wing venation separate this taxon from other genera of Hepialidae although four derived characters states are shared in common with the cibyrine clade. The holotype male is deposited in the collection of the Museo de Historia Natural, Lima, Peru.

A new Peruvian species and new records of the genus Elmas Blackwelder(Coleoptera: Staphylinidae).

Elmas gorky Rodríguez et al. new species, is described from the department of Madre de Dios in southeastern Peru. Major diagnostic features are photographed and illustrated. New records are provided for Elmas gigas Ashe Chatzimanolis, Elmas lescheni Ashe Chatzimanolis and Elmas strigella (Bernhauer).

A new record of a giant neoepiblemid rodent from Peruvian Amazonia and an overview of lower tooth dental homologies among chinchilloids

We report here a new record of the giant caviomorph Phoberomys corresponding to a fragmentary mandible from the Monte Salvado area, Peruvian Amazonia (Madre de Dios Department). We describe this specimen and compare it with the material previously attributed to Phoberomys. The mandibular fragment is referred to as Phoberomys sp. Found as float on a bank of the Rio Las Piedras, it has been hypothetically assigned a late Miocene age, due to the local/regional stratigraphic and lithologic context. This specimen constitutes the second record of Phoberomys in Peru. For the first time, the pattern of p4s and lower molars in Phoberomys was analyzed and compared to a large taxonomic sample (in-cluding Paleogene-Recent chinchilloids and other caviomorphs) in order to progress the understanding of the homology of dental structures in this genus. For p4s and lower molars, the position of the protoconid in Phoberomys and other chinchilloids (Drytomomys sp., Potamarchus, Eumegamys, Gyriabrus, Isostylomys, and Tetrastylus) is ambiguous, and as a result we propose two alternative homology hypotheses for these taxa: protoconid within the first and second laminae or within the third lamina on juvenile specimens. The knowledge of a comprehensive ontogenetic sequence in extinct and extant chinchilloids, associated with more complete palaeontological records, would likely allow for a clarification of these homology ambiguities.

Identification of Leptospira and Bartonella among rodents collected across a habitat disturbance gradient along the Inter-Oceanic Highway in the southern Amazon Basin of Peru.

BackgroundThe southern Amazon Basin in the Madre de Dios region of Peru has undergone rapid deforestation and habitat disruption, leading to an unknown zoonotic risk to the growing communities in the area.Methodology/Principal findingsWe surveyed the prevalence of rodent-borne Leptospira and Bartonella, as well as potential environmental sources of human exposure to Leptospira, in 4 communities along the Inter-Oceanic Highway in Madre de Dios. During the rainy and dry seasons of 2014–2015, we captured a total of 97 rodents representing 8 genera in areas that had experienced different degrees of habitat disturbance. Primarily by using 16S metagenomic sequencing, we found that most of the rodents (78%) tested positive for Bartonella, whereas 24% were positive for Leptospira; however, the patterns differed across seasons and the extent of habitat disruption. A high prevalence of Bartonella was identified in animals captured across both trapping seasons (72%–83%) and the relative abundance was correlated with increasing level of land disturbance. Leptospira-positive animals were more than twice as prevalent during the rainy season (37%) as during the dry season (14%). A seasonal fluctuation across the rainy, dry, and mid seasons was also apparent in environmental samples tested for Leptospira (range, 55%–89% of samples testing positive), and there was a high prevalence of this bacteria across all sites that were sampled in the communities.Conclusions/SignificanceThese data indicate the need for increased awareness of rodent-borne disease and the potential for environmental spread along the communities in areas undergoing significant land-use change.

Predictors of mitochondrial DNA copy number and damage in a mercury-exposed rural Peruvian population near artisanal and small-scale gold mining: An exploratory study.

Mitochondrial DNA (mtDNA) copy number (CN) and damage in circulating white blood cells have been proposed as effect biomarkers for pollutant exposures. Studies have shown that mercury accumulates in mitochondria and affects mitochondrial function and integrity; however, these data are derived largely from experiments in model systems, rather than human population studies that evaluate the potential utility of mitochondrial exposure biomarkers. We measured mtDNA CN and damage in white blood cells (WBCs) from 83 residents of nine communities in the Madre de Dios region of the Peruvian Amazon that vary in proximity to artisanal and small-scale gold mining. Prior research from this region reported high levels of mercury in fish and a significant association between food consumption and human total hair mercury level of residents. We observed that mtDNA CN and damage were both associated with consumption of fruit and vegetables, higher diversity of fruit consumed, residential location, and health characteristics, suggesting common environmental drivers. Surprisingly, we observed negative associations of mtDNA damage with both obesity and age. We did not observe any association between total hair mercury or, in contrast to previous results, age, with either mtDNA damage or CN. The results of this exploratory study highlight the importance of combining epidemiological and laboratory research in studying the effects of stressors on mitochondria, suggesting that future work should incorporate nutritional and social characteristics, and caution should be taken when applying conclusions from epidemiological studies conducted in the developed world to other regions, as results may not be easily translated. Environ. Mol. Mutagen. 60: 197-210, 2019. © 2018 Wiley Periodicals, Inc.

Fire- and distance-dependent recruitment of the Brazil nut in the Peruvian Amazon

The low natural regeneration of the Brazil nut (Bertholletia excelsa) in the Madre de Dios region of Peru is a major concern for the conservation and sustainable use of this species which sustains one of the cornerstone non-timber forest product economies in Amazonia. The Brazil nut is a gap-dependent, long-lived pioneer species that has been shown to regenerate more effectively in fallows than in mature forests. Aside from light and nutrient availability, recruitment success of the species might also be influenced by conspecific negative distance-dependent (CNDD) processes as shown for a myriad of other tropical tree species, but to date has not been studied in the Brazil nut. We measured Brazil nut recruitment in forty 150 × 10 m2 transects (totaling 6 ha), proportionally laid out in mature forest and fallow land. We found a higher likelihood of regeneration in fallows than in mature forest, which was mainly due to more successful transitioning from seedlings to saplings in fallows. Recruitment rates in fallows increased with the number of fire events occurring over the past 12 years, largely owing to the accumulation of resprouting individuals, but this positive correlation was only observed up to three fire events. We observed CNDD recruitment of the Brazil nut in fallows but not in mature forest, suggesting that pests and diseases might also condition Brazil nut recruitment. Our findings suggest that a better management of fallow land and more controlled use of fire in neighboring land uses could be a cost-effective manner to create Brazil nut rich forests through natural regeneration. On the other hand, the absence of high density Brazil nut stands in mature forests in Madre de Dios might mean that the impact of ancient humans there has been more limited than in other Amazonian regions.

First documented record of the Stripe-backed Bittern, Ixobrychus involucris (Vieillot, 1823) (Aves, Ardeidae) in Peru

We report the sighting and capture of a Stripe-backed Bittern, Ixobrychus involucris (Vieillot, 1823), in the Reserva Ecológica Taricaya, 26 km northeast of Puerto Maldonado on the margin of the Madre de Dios River, department of Madre de Dios, southeast Peru. This record confirms the presence of the species for the country, likely as a rare austral migrant. There have been 4 undocumented observations in 40 years, all of them restricted to the Madre de Dios department in the extreme southeast of the country.

First documented record of the Stripe-backed Bittern, Ixobrychus involucris (Vieillot, 1823) (Aves, Ardeidae) in Peru

We report the sighting and capture of a Stripe-backed Bittern, Ixobrychus involucris (Vieillot, 1823), in the Reserva Ecológica Taricaya, 26 km northeast of Puerto Maldonado on the margin of the Madre de Dios River, department of Madre de Dios, southeast Peru. This record confirms the presence of the species for the country, likely as a rare austral migrant. There have been 4 undocumented observations in 40 years, all of them restricted to the Madre de Dios department in the extreme southeast of the country.

Mining Formalization at the Margins of the State: Small‐scale Miners and State Governance in the Peruvian Amazon

ABSTRACTThis article analyses the Peruvian government's quest to formalize small‐scale mining in the Amazon as a political process which shows how state governance problems are reproduced in the margins of the state. It asks why the central state is unable to govern mining activities in the Madre de Dios region, and examines how small‐scale miners have reacted to state attempts to formalize their activities. The author argues that, through political agency and the reproduction of ‘hybrid’ formal and informal institutions, small‐scale miners have learned to contest, reinterpret and build alternatives to central state governance. The article contributes to the literature on development policies by showing how difficulties in implementing regulatory policies may be analysed as governance problems, particularly in regions like the Amazon, where the state apparatus is not well established.

Evaluating Wildlife Vulnerability to Mercury Pollution From Artisanal and Small-Scale Gold Mining in Madre de Dios, Peru

Illegal, artisanal and small-scale gold mining (ASGM) often occurs in remote highly biodiverse areas, such as the Madre de Dios region of Peru. Mercury used in gold mining bioaccumulates in the environment and poses developmental, hormonal, and neurological threats to wildlife. The impact of ASGM on biodiversity remains largely unknown. We used geographic information science to create a spatial model of pollution risk from mining sites, in order to predict locations and species assemblages at risk. Multicriteria evaluation was used to determine how flow accumulation, distance from mining areas, total suspended sediment load, and soil porosity influenced the vulnerability of regions to mercury pollution. Results suggest that there is considerable opportunity for protection of areas with high biodiversity and vulnerability north of the Madre de Dios River where much of the land is not protected. Our study highlights the need for future ASGM research to consider more than deforestation risk alone while protecting the areas’ unmatched biodiversity.

My experiences with Indigenist methodologies

AbstractTraditionally, geographic research and engagement with Indigenous communities have largely been developed within a western research paradigm and have historically been linked to colonial practices such as extraction and/or domination. The consequences of these research practices and paradigms have been the further marginalisation of Indigenous people globally. However, geographers are increasingly being influenced by a range of Indigenous scholars from both within and beyond the discipline who highlight the colonial foundations of geographic knowledge and the ongoing production of colonial relations, and who are calling for a decolonisation of knowledge through the use of Indigenist methodologies. After exploring this shift, this paper moves to a discussion of my engagement with research in Indigenous communities using Indigenist methodologies, including the emotions and thought processes that emerged during my own research journey, which led me to southern Guyana and the Makushi and Wapishana peoples who reside in the northern savannah environments of the Amazon basin. I conclude by sharing how I am continuing that journey using Indigenist approaches in my work in the Madre de Dios region of Peru, and by encouraging future scholars to challenge traditional geographic research methods.

Determinación de polos de generación distribuida a partir de biomasa residual agrícola en la región Madre de Dios, Perú

Contexto: la región Madre de Dios, Perú, se encuentra condicionada por la forma del asentamiento disperso de sus poblaciones. Esta configuración limita el acceso de la energía a centros poblados rurales, que se encuentra en 69% en la población rural; por ello, esta investigación tuvo como objetivo principal la determinación de polos de generación distribuida a partir de biomasa residual agrícola en la región de Madre de Dios.Método: mediante un esquema metodológico de cuatro fases, se analizó la cobertura eléctrica de la región Madre de Dios y se priorizaron centros poblados rurales con mayor posibilidad de energización; posteriormente, se determinó la cantidad de biomasa residual agrícola de los cultivos mayoritarios en la región y su localización geográfica. Seguidamente, se analizaron las opciones tecnológicas de aprovechamiento energético disponibles; por último, se estimó la cantidad de energía aprovechable de la biomasa residual agrícola.Resultados: se determinaron cinco centros poblados rurales priorizados en Madre de Dios para la energización. En cuanto a la biomasa residual agrícola, ésta se estimó en 6645.08 ton/año para arroz, 5191.20 ton/año para maíz amarillo duro y 7862.37 ton/año para plátano, los tres cultivos mayoritarios en la región. Se estimó que, para el aprovechamiento de cascarilla de arroz, el rango de generación de energía varía de 838.86 a 1319.23 KWh/año mediante gasificadores de lecho móvil, y de 317.99 a 897.56 KWh/año para gasificadores de lecho fluidizado, con lo cual se cubriría la demanda energética de los centros poblados rurales priorizados, que asciende a 211.9 MWh/año.Conclusiones: la región de Madre de Dios cuenta con potencial de generación de energía eléctrica distribuida que puede cubrir la demanda de los cinco centros poblados priorizados al 100%. Asimismo, la energía generada en la región Madre de Dios mediante lecho fluidizado podría atender la demanda de 1495 habitantes aproximadamente, mientras que mediante lecho móvil se cubriría la demanda de 3945 habitantes aproximadamente.