Fogo e artesanato de capim-dourado no Jalapão - usos tradicionais e consequências ecológicas

Abstract

Over the past decade, the handicrafts produced from flower stalks of ‘golden-grass' (Syngonanthus nitens, Eriocaulaceae) and young leaves of the buriti palm (Mauritia flexuosa, Arecaceae) became a trademark of Jalapão region, and the whole state of Tocantins. Fire is used as a management tool to stimulate golden-grass flower production. In this paper, we synthetize results from ethnoecological studies carried out between 2002 and 2011 in cooperation with local communities and environmental managers. The studies focused on the effects of harvesting on both golden-grass and buriti palms, as well as on the effects of fire on golden-grass populations. Biennial fires stimulated golden-grass flowering, which is consistent with the knowledge of experienced harvesters. Stochastic simulations revealed that biennial fires also yield the highest long-term stochastic population growth rates. Longer fire return intervals were not shown to promote golden-grass flowering, but do not cause population declines. Golden-grass populations are highly resistant to fire. On the other hand, their demography varies greatly with inter-annual variation in rainfall. These features are likely shared with dozens of other vascular plant species in the wet grasslands of the Cerrado. Flower stalk harvesting after September 20th, as required by state legislation in Tocantins, had no negative effects on golden-grass individuals or populations. The harvesting intensity of buriti youngleaves as carried out in the Jalapão region had no negative effects on buriti individuals or populations. The regulations in place prevent early harvesting of golden-grass, which causes strong population declines, and is appropriate for the whole state of Tocantins. Preventing early harvesting must involve both spreading information as well as law enforcement activities. The use of controlled fires should be promoted as a strategy to decrease the occurrence of uncontrolled, extensive fires. This can only be achieved by involving and training local communities. The use of controlled fires in wet grasslands for golden-grass management should be performed with extreme care to avoid damaging fire sensitive physiognomies, especially buriti-dominated swampy forests