title: The effect of management systems and ecosystem types on bark regeneration in Himatanthus drasticus (Apocynaceae): recommendations for sustainable harvesting.
abstract: Bark and exudates are widely commercialized non-timber forest products. However, the ecological impacts of the harvesting of these products have seldom been studied. The aim of this study is to investigate the relationship of tree resilience to harvesting intensity in Himatanthus drasticus, a tree that is highly exploited in the Brazilian savanna (Cerrado) for its medicinal latex. Although the traded product is the latex, the traditional harvesting systems involve the removal of the bark of the trees to allow exploitation. A 3-year experiment was conducted in two different Cerrado ecosystems (open savanna and savanna woodland). Trees were debarked at four debarking intensities to simulate the effects of traditional management systems. Measurements of bark growth were taken every 6 months, and quantitative and qualitative indexes of bark regeneration were obtained. The mortality of the debarked trees was low and could not be related to the intensity of harvesting. No signs of attack by fungi or insects were recorded. Compared with other species exploited for bark, H. drasticus is very resilient to harvesting; however, bark regeneration is relatively slow. In both analyzed ecosystems, the regeneration indexes showed higher values in the controls than in the treatments, indicating that 3 years is not sufficient for total recovery of the rhytidome. Bark regeneration occurred primarily by sheet growth and was more rapid in open savanna than in savanna woodland. No differences in the rate of bark recovery were found among management treatments. Based on the results, sustainable harvesting guidelines are suggested for the species.
authors: Cristina
authors: C
authors: Baldauf
authors: Flavio Antonio
authors: FA
authors: Maës dos Santos
mesh_terms: D029062:Apocynaceae / Q000254:growth & development*; D001938:Brazil; D003247:Conservation of Natural Resources / Q000379:methods*; D017753:Ecosystem; D004784:Environmental Monitoring; D016468:Forestry / Q000379:methods*; D024301:Plant Bark / Q000254:growth & development*
references: Ann Bot. 2002 Jun;89(6):773-82
references: 12102533
references: Environ Monit Assess. 2011 Sep;180(1-4):31-9
references: 21069455
references: Fitoterapia. 2004 Dec;75(7-8):750-3
references: 15567256
references: Environ Monit Assess. 2013 Apr;185(4):2921-8
references: 22773145
references: Proteomics. 2006 Feb;6(3):881-95
references: 16385474
references: Pharmacognosy Res. 2010 Sep;2(5):309-12
references: 21589758
references: J Inflamm (Lond). 2010 Dec 17;7:60
references: 21167055
references: Phytother Res. 2004 Aug;18(8):670-3
references: 15476301
references: PLoS One. 2012;7(6):e39810
references: 22787521
references: J Ethnobiol Ethnomed. 2009 Dec 15;5:40
references: 20003502
references: J Ethnopharmacol. 2011 Sep 1;137(1):421-6
references: 21679758