Chronosequence of Natural Regeneration in Abandoned Mining Sites in the Amazon Rainforest of Madre De Dios, Peru
Edson J. MORALES-PARRA1,2*, Nobuyiki TANAKA1, Martin PILLACA3, Francisco ROMÁN-DAÑOBEYTIA3,4 Luis E. FERNANDEZ 3,4 and Miles SILMAN 3,4
1Department of International Agricultural Development, Tokyo University of Agriculture, Tokyo, Japan
2Amazonian Scientific Innovation Center (CINCIA), Madre de Dios, Peru
3Geographic Information Systems Department, Amazonian Scientific Innovation Center (CINCIA), Madre de Dios, Peru
4Center for Energy, Environment and Sustainability and Department of Biology, Wake Forest University, NC 27106, USA
Abstract: Gold extraction via small scale mining in the Amazon rainforest of Peru has become one of the greatest threats to deforestation and land degradation in the Amazon, especially in the Madre de Dios region which is one of the last biggest remnants of continuous tropical rainforest in the world. Restoration of these degraded ecosystems have become a priority in the last decade but without concrete actions, however, few research has been conducted in response to these restoration activities nor natural regeneration. The significance of this research was to study a chronosequence of natural regeneration in two active gold-mining sites in Madre de Dios-Peru (Paolita-PA; Santa Rita-ST) and how the nearby remnant forest contribute to natural regeneration. Sites were chosen depending on its management and the proximity to nearby remnant forest. Floristic composition of natural regeneration following abandonment of mining activities was studied by establishing a total of 12 plots (20x50m each), 6 with an abandonment period of 2 to 16 years and 6 were considered as reference forest. A total of 753 individuals from 44 families and 144 species were identified. To analyze biodiversity and similarity composition, Shannon and Jaccard indexes were used, respectively. The results showed that the abundance of species (Shannon) was higher in Paolita than in the Santa Rita mining site. From Jaccard’s similarity index each mining site was analyzed in clusters finding that in Paolita, nearby remnant forest might not have a great influence over natural regeneration when compared with Santa Rita site which showed similarity between remnant forest, but instead the time of abandonment, availability of nutrients and forest fragmentation might be the cause of the recovery of degraded forest.
Keywords: Chronosequence, Natural regeneration, Gold mining, Amazon rainforest, Peru.