Natural Regeneration After Gold Mining in the Peruvian Amazon: Implications for Restoration of Tropical Forests

Context: Gold mining is the most destructive activity in the natural forests of the Madre de Dios region in the southeastern Peruvian Amazon. Understanding the natural regeneration process of these degraded areas is necessary to develop forest restoration projects in such conditions.Aims: We aimed to evaluate forest recovery and identify the successional and structure patterns of vegetation governing natural regeneration over time.Methods: Structure, composition, richness, diversity, and successional status were evaluated in abandoned artisanal gold mine areas in Madre de Dios, southeastern Peru. Vegetation data were recorded in 61 plots of 250 m2 established in five sites varying from 1 to 19 years of abandonment. Vegetation in abandoned areas was compared with six undisturbed forests evaluated in previous inventories.Results: In the mining lands, tree density and basal area recovered quickly, while species richness and composition were slow. Forest recovery is an initial stage of transition from pioneer to early secondary species until at least 19 years after abandonment. The most abundant and frequent species were the fast-growing species Ochroma pyramidale and Cecropia engleriana. These species could be considered potential candidates to promote restoration plans. Pioneer species represented 63% of the number of species in plots of 1–4 years, 57% in plots of 5–7 years, and 50% in plots of 8–19 years. Early and late secondary species represented 34 and 16%, respectively, of the number of species in plots of 8–19 years. Abandoned mining and reference plots present less than 5% of species in common.Conclusion: Our results highlight a slow natural regeneration process in areas for up to 19 years after gold mining. Species from different successional statuses were identified as potential candidates for recovering vegetation in such areas. Our findings may have important implications for further research focusing on the ecological restoration in tropical forests severely degraded by gold mining.

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

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1907842116 ◽

2019 ◽

Vol 116 (48) ◽

pp. 23936-23941 ◽

Cited By ~ 7

Author(s):

Evan N. Dethier ◽

Shannon L. Sartain ◽

David A. Lutz

Keyword(s):

Suspended Sediment ◽

Tropical Forests ◽

Gold Mining ◽

Hot Spot ◽

Sediment Concentration ◽

Fish Diversity ◽

Spatial And Temporal Patterns ◽

Tropical Biodiversity ◽

Madre De Dios ◽

Landsat Satellite

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.

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How can molecular ecology contribute to forest restoration?

Journal of Biotechnology and Biodiversity ◽

10.20873/jbb.uft.cemaf.v4n4.siqueira ◽

2013 ◽

Vol 4 (4) ◽

pp. 316-321

Author(s):

Marcos Vinicius Bohrer Monteiro Siqueira ◽

Patricia Sanae Sujii ◽

Miklos Bajay ◽

Carolina Grando ◽

Kaiser Schwarcz ◽

...

Keyword(s):

Tropical Forests ◽

Forest Restoration ◽

Population Studies ◽

Molecular Ecology ◽

Point Of View ◽

Molecular Techniques ◽

Forest Recovery ◽

Main Ideas ◽

New Strategies

The advance of scientific knowledge in various areas of molecular ecology has allowed the adoption of new strategies, particularly in forest restoration. The fusion of multidisciplinary areas and the implementation of management methodologies in order to get better results in forest restoration are current realities. In order to review the main ideas about the role of molecular techniques in the service of ecology restoration, this paper outlines how forest recovery can benefit from genetic and genomic plant population studies. The next challenges in conservation genetics can be brought by the quest for more efficient forest restorations from the point of view of biodiversity as well as the ecological ynamics as a whole. It is believed that in the coming years we will observe integrated strategies in molecular ecology with specific methodologies for restoration in tropical forests.

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Natural regeneration of subtropical montane forest after clearing fern thickets in the Dominican Republic

Journal of Tropical Ecology ◽

10.1017/s0266467404001646 ◽

2004 ◽

Vol 20 (4) ◽

pp. 483-486 ◽

Cited By ~ 29

Author(s):

Matthew G. Slocum ◽

T. Mitchell Aide ◽

Jess K. Zimmerman ◽

Luis Navarro

Keyword(s):

Soil Moisture ◽

Tropical Forests ◽

Natural Regeneration ◽

Dispersal Limitation ◽

Anthropogenic Disturbances ◽

Montane Forest ◽

Tree Regeneration ◽

Forest Recovery ◽

Moderate Intensity ◽

Succession Process

Tropical forests can recover after anthropogenic disturbances of light to moderate intensity (Aide et al. 1995, 1996, 2000; Uhl 1987, Uhl et al. 1988); however, severe disturbances (e.g. compaction or loss of soil) often result in conditions that prevent forest recovery. These degraded sites are often dominated by grasses (Aide & Cavelier 1994, Cabin et al. 2002, Cavelier et al. 1998, Uhl et al. 1988) and ferns (Cohen et al. 1995, García et al. 1994, Slocum et al. 2000, Walker & Boneta 1995) that can impose barriers for tree regeneration and arrest the succession process. Important barriers for tree regeneration include: (1) competition with grasses and ferns for soil moisture, nutrients and light (Aide & Cavelier 1994, Guimarães-Vieira et al. 1994, Holl et al. 2000, Nepstad et al. 1996, Russell et al. 1998, Walker 1994, Zimmerman et al. 2000), and (2) dispersal limitation given that grasses and fernlands offer few resources that attract seed dispersers (Guevara & Laborde 1993, Holl et al. 2000, McDonnell & Stiles 1983, Slocum & Horvitz 2000, Zimmerman et al. 2000).

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Unstable Malaria Transmission in the Southern Peruvian Amazon and Its Association with Gold Mining, Madre de Dios, 2001–2012

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.16-0030 ◽

2016 ◽

Vol 96 (2) ◽

pp. 304-311 ◽

Cited By ~ 13

Author(s):

Juan F. Sanchez ◽

Andres M. Carnero ◽

Esteban Rivera ◽

Luis A. Rosales ◽

G. Christian Baldeviano ◽

...

Keyword(s):

Malaria Transmission ◽

Gold Mining ◽

Peruvian Amazon ◽

Madre De Dios

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Expansion of small-scale gold mining in Madre de Dios: ‘capital interests’ and the emergence of a new elite of entrepreneurs in the Peruvian Amazon

The Extractive Industries and Society ◽

10.1016/j.exis.2019.01.002 ◽

2019 ◽

Vol 6 (2) ◽

pp. 382-389 ◽

Cited By ~ 8

Author(s):

Dolores Cortés-McPherson

Keyword(s):

Gold Mining ◽

Small Scale ◽

Peruvian Amazon ◽

Madre De Dios

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Forest restoration in the floodplains of the Amazon estuary subjected to intensive açaí management

Ambiente & sociedade ◽

10.1590/1809-4422asoc20180269r3vu2021l2ao ◽

2021 ◽

Vol 24 ◽

Author(s):

Rosileia da Costa Carvalho ◽

Lívia de Freitas Navegantes Alves ◽

Renan do Vale Carneiro

Keyword(s):

Natural Regeneration ◽

Native Species ◽

Forest Restoration ◽

Floristic Composition ◽

Floodplain Forest ◽

Forest Recovery ◽

Floodplain Forests ◽

Structured Interviews ◽

Ecosystem Conservation ◽

Amazon Estuary

Abstract The expansion and intensification of açaí management in floodplain forests of the Amazonian estuary have resulted in changes in floristic composition and in biodiversity losses, causing problems to ecosystems and endangering livelihoods of riverine communities. These transformations have prompted the need for forest restoration. The objective of this study was to identify and analyze forest recovery initiatives carried out in floodplain forests previously subjected to intensive açaí management in the Amazonian estuary. Methods included structured interviews and questionnaires. Results reveled the following restoration types: 1) area enrichment: subtype 1 - high floodplain forest (7.89%) and subtype 2 - low floodplain forest (44.75%); 2) directing natural regeneration of native species (34.21%); 3) cultivation of native species (13.15%). Results suggest that forest restoration efforts can promote sustainable production of açaí, productive diversity, ecosystem conservation and generate income for riverine families.

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The scientists restoring a gold-mining disaster zone in the Peruvian Amazon

Nature ◽

10.1038/d41586-020-00119-z ◽

2020 ◽

Author(s):

Jeff Tollefson

Keyword(s):

Gold Mining ◽

Peruvian Amazon

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FRUGIVORIA E DISPERSÃO DE SEMENTES POR PEIXES

Scientific Magazine UAKARI ◽

10.31420/uakari.v1i1.2 ◽

2008 ◽

Vol 1 (1) ◽

pp. 7-18

Author(s):

Luciane Lopes de Souza

Keyword(s):

Sustainable Development ◽

Seed Dispersal ◽

Tropical Forests ◽

Natural Regeneration ◽

Main Species ◽

Fishing Gears ◽

Solimões River

Biotic or abiotic processes of seed dispersal are important for the maintenance of the diversity, and for the natural regeneration in tropical forests. Ichthyochory is one of the fundamental mechanisms for seed dispersal in flooded environments, as the igapó forests. A study on the ichthyochory of the igapós was conducted at Amanã Sustainable Development Reserve, in the middle Solimões river, from June 2002 to September 2004. Monthly samples of frugivorous fish were taken, with the main fishing gears used locally. Guts of 1,688 fish caught were examined. The main species were Myloplus rubripinnis (29.21%), Hemiodus immaculatus (18.96%),Colossoma macropom um (16.23%) and Mylossoma duriventre (16.05%). The diet was made of vegetables (fruits, leave and flowers), and animals (arthropods). 53.02% of all fish caught ingested fruits. The total number of intact seeds in the stomachs and intestines were 8,069 and 5,763 respectively. About 61.9% of the Brycon melanopterus (matrinchão), 46.34% of the Brycon amazonicus (mamuri) and 30.22% of M . rubripinnis (parum ) analysed had intact seeds in their guts. Seeds of Nectandra amazonum and Genipa spruceana ingested proved to be more viable than those non-ingested by fish. The high rates of frugivory, the presence of intact seeds in the guts of fish and the greater viability of ingested seeds all suggest that these animals are important seed dispersors in the igapó forests of Amanã Reserve.

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