Threats to biological diversity caused bycoca/cocaine deforestation in Peru

Summary Indirect sources were used to characterize the nature and magnitude of threats to the native plants and forest ecosystems caused by the cultivation and control of coca , the precursor to cocaine, in the Huallaga valley of Peru, whence the majority of the world's cocaine originates. Deforestation is concentrated between 500 and 2000 m in the tropical premontane forest belt. Recent listing of Peru's seed plants permitted a quantification of plant species known from the department of San Martin between 500–2000 m and thus at risk due to forest degradation. This flora consists of 169 plant families, almost 900 genera, and about 2600 species. Fifteen percent of the species are restricted in distribution to Peru, while 6% are known only from San Martin. An additional 778 species, including 46 narrow endemics, are known from vegetation types found below 500 m. More than 223 000 ha of land were found to be in ‘hill agriculture’, consisting predominantly of coca fields and this suggests that the total impact of coca /cocaine deforestation is greatly under-estimated by using simply the area of coca under cultivation. Degraded tropical pre-montane forest may amount to as much as 1 000 000 ha in all of Peru.