Soil-mediated effects on potential Euterpe edulis (Arecaceae) fruit and palm heart sustainable management in the Brazilian Atlantic Forest

• Published in: Forest ecology and management 2012-11, Vol.284, p.78-85
• Main Authors: Brancalion, Pedro H.S., Vidal, Edson, Lavorenti, Norberto A., Batista, João Luís F., Rodrigues, Ricardo R.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Arecaceae; Biological and medical sciences; Euterpe edulis; Exploitation; Forestry; Forests; Fruits; Fundamental and applied biological sciences. Psychology; Harvesting regime; Heart; Keystone palm; Management; Non-timber forest products; Overharvesting; Palm; Populations; Resource management; Synecology; Terrestrial ecosystems
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2012.07.028

► Sodium and potassium played a key role in Euterpe edulis fruit and palm heart yield. ► Restinga populations would not be suitable for fruits and palm heart management. ► A habitat-specific approach of sustainable management is needed for E. edulis. ► General models of low impacting harvesting may be unsuccessful for widespread species. Euterpe edulis is an endangered species due to palm heart overharvesting, the most important non-timber forest product of the Brazilian Atlantic Forest, and fruit exploitation has been introduced as a low impacting alternative. However, E. edulis is a keystone species for frugivores birds, and even the impact of fruit exploitation needs to be better investigated. Since this species occurs over contrasting habitats, the establishment of site-specific standards and limits for exploitation may also be essential to achieve truly sustainable management. In this context, we sought to investigate how soil chemical composition would potentially affect E. edulis (Arecaceae) palm heart and fruit exploitation considering current standards of management. We studied natural populations found in Restinga Forest and Atlantic Rainforest remnants established within Natural Reserves of São Paulo State, SE Brazil, where 10.24ha permanent plots, composed of a grid of 256 subplots (20m×20m), were located. In each of these subplots, we evaluated soil chemical composition and diameter at breast height of E. edulis individuals. Additionally, we evaluated fruit yield in 2008 and 2009 in 20 individuals per year. The Atlantic Rainforest population had a much higher proportion of larger diameter individuals than the population from the Restinga Forest, as a result of habitat-mediated effects, especially those related to soil. Sodium and potassium concentration in Restinga Forest soils, which have strong negative and positive effect on palm growth, respectively, played a key role in determining those differences. Overall, the number of fruits that could be exploited in the Atlantic Rainforest was four times higher than in Restinga Forest. If current rules for palm heart and fruit harvesting were followed without any restriction to different habitats, Restinga Forest populations are under severe threat, as this study shows that they are not suitable for sustainable management of both fruits and palm heart. Hence, a habitat-specific approach of sustainable management is needed for this species in order to respect the demographic and ecological dynamics