BackgroundThere have been few studies on the sustainable use of non-timber forest products in arid and semi-arid zones. The palm Brahea dulcis has been one of the most important resources in semi-arid Mesoamerica, since pre-Hispanic times. Currently, some populations grow within protected natural areas, representing both a challenge and an opportunity for local development. This ethnoecological study of B. dulcis in central Mexico aimed to evaluate their uses, harvesting context, and potential for exploitation, in order to give practical advice on their best use and management.MethodsEthnographic and ecological information was obtained in Barranca de Metztitlán Biosphere Reserve and Valle del Mezquital, Mexico. We studied the population structure and density; additionally, we evaluated the rate of leaf production, leaf renewal rate, percent survival of new leaves, the development of reproductive structures and performed a one-year defoliation experiment (involving a control and four treatments including a mix of semiannual and annual frequency of harvest and removal of two new leaves and/or two mature leaves).ResultsTwenty uses of the palm were recorded in the study area. Religious/symbolic and handicraft uses are highlighted. The population density of this species was the highest reported for the genus (1244 ± 231.7 ind/ha). The leaf production rate was the highest reported for arborescent palms of the Americas (11.83 ± 0.036 leaves/individual/year). The sexual reproductive cycle was 2.3 years long. A one-year defoliation experiment did not show statistically significant differences. Recommendations include: 1) implement management focused on increasing the abundance and quality of this useful resource in Metztitlán; 2) employ a strategy of focusing on ethnicity and gender in promoting their exploitation; 3) learn from theoretical frameworks of other non timber forest product studies.ConclusionsWe propose that Brahea dulcis is the palm with the highest potential for sustainable use in the arid and semi-arid zones of Mexico. The challenge to improving management includes simplifying the legal protection framework, promoting uses and developing a market strategy. Collaborations to share experiences with peasant farmers from Guerrero is recommended. We further recommend the development of a governmental strategy to enhance and reassess this important resource.Electronic supplementary materialThe online version of this article (doi:10.1186/1746-4269-11-1) contains supplementary material, which is available to authorized users.

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To understand the population dynamics of a species, it is necessary to document the way in which its demographic behaviour varies through space and time. Anthropogenic disturbance, such as shifting cultivation, is an important factor causing demographic variation in many tropical non-timber forest products. The leaves of the palm Sabal yapa are an important non-timber forest product used for thatching by Mayan peoples. The demography of Sabal yapa was studied in three habitats (mature forest, successional forest and crop fields), representing successional phases along the slash-and-burn agricultural cycle in the Yucatan Peninsula. Matrix population models, along with elasticity analyses and life-table-response experiments were employed. Population growth rate differed between patches (MF: λ = 1.043; SF: λ = 1.027; CF: λ = 0.959). Only the λ value of the mature forest was significantly higher than unity. Fecundity and seedling survival were lowest in the crop fields and highest in the mature forest. The elasticity analyses and life-table-response experiments showed that entries with a high positive contribution to λ also showed high elasticity values, while those with a negative contribution to λ showed low elasticity. Thus, both analyses are crucial to understand the demography of a species and to aid in conservation and management practices.

Shifting cultivation is often perceived to be a threat to forests, but it is also central to the culture and livelihoods of millions of people worldwide. Balancing agriculture and forest conservation requires knowledge of how agricultural land uses evolve in landscapes with forest conservation initiatives. Based on a case study from Quintana Roo, Mexico, and remote sensing data, we investigated land use and land cover change (LUCC) in relation to accessibility (from main settlement and road) in search of evidence for agricultural expansion and/or intensification after the initiation of a community forestry program in 1986. Intensification was through a shortening of the fallow period. Defining the sampling space as a function of human needs and accessibility to agricultural resources was critical to ensure a user-centered perspective of the landscape. The composition of the accessible landscape changed substantially between 1976 and 1997. Over the 21-year period studied, the local population saw the accessible landscape transformed from a heterogeneous array of different successional stages including mature forests to a landscape dominated by young fallows. We detected a dynamic characterized by intensification of shifting cultivation in the most accessible areas with milpas being felled more and more from young fallows in spite of a preference for felling secondary forests. We argue that the resulting landscape provides a poorer resource base for sustaining agricultural livelihoods and discuss ways in which agricultural change could be better addressed through participatory land use planning. Balancing agricultural production and forest conservation will become even more important in a context of intense negotiations for carbon credits, an emerging market that is likely to drive future land changes worldwide.

The Mauritia flexuosa L.f. palm is known as the “tree of life” given its importance as fundamental food and construction resources for humans. The species is broadly distributed in wet habitats of Amazonia and dry habitats of the Amazon and Orinoco river basins and in the Cerrado savanna. We collected 179 individuals from eight different localities throughout these habitats and used microsatellites to characterize their population structure and patterns of gene flow. Overall, we found high genetic variation, except in one savanna locality. Gene flow between populations is largely congruent with river basins and the direction of water flow within and among them, suggesting their importance for seed dispersal. Further, rivers have had a higher frequency of human settlements than forested sites, contributing to population diversity and structure through increased human use and consumption of M. flexuosa along rivers. Gene flow patterns revealed that migrants are sourced primarily from within the same river basin, such as those from Madeira and Tapajós basins. Our work suggests that rivers and their inhabitants are a critical element of the landscape in Amazonia and have impacted the dispersal and subsequent distribution of tropical palm species, as shown by the patterns of genetic variation in M. flexuosa.

This paper scrutinises claims made about the promise and efficacy of ecosystems-based adaptation (EBA), through an exploration of EBA-relevant interventions in two fieldsites in Mexico. Our data starts to fill important gaps in current global debates about EBA. We find evidence of the important contribution of interventions relevant to EBA objectives at a small scale and under very specific conditions. However, the viability of similar interventions is substantially reduced, and arguably rendered null, as an incentive for conservation in a more populous fieldsites. Furthermore, evidence suggests that other adaptation options risked being overlooked if the context were viewed solely through the lens of EBA. We conclude that EBA needs to: a) engage with and address the trade-offs which characterised earlier attempts to integrate conservation and development, and; b) acknowledge the implications for its objectives of a globally predominant, neoliberal political economy.

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Resumo O objetivo desta pesquisa foi estudar o conhecimento ecológico tradicional (CET) relacionado à pesca feita por grupo étnico autoidentificado como quilombola, por meio da análise de fatores que influenciam o consenso cultural e as técnicas da pesca artesanal. Participaram 24 homens e sete mulheres dos quilombos Retiro, Boqueirão, Casalvasco e Manga. Os métodos de amostragem utilizados foram: bola de neve, lista livre e observação participante. Os resultados incluem 47 etnoespécies (46 peixes e um réptil). O consenso cultural é composto por: Hoplias malabaricus, Cichla sp., Pseudoplatystoma fasciatum, Astronotus ocellatus, Satanoperca pappaterra, Brycon cephalus, Piaractus mesopotamicus, P. corruscans, Pimelodus sp., Colossoma macropomum, Pygocentrus nattereri, Mylossoma aureum, Astyanax sp. e Leporinus freiderici. Embora tenha sido maior a riqueza do conhecimento entre pessoas que residiram temporariamente em outros estados brasileiros, este aspecto não esteve relacionado à idade dos entrevistados. A manutenção e a transmissão de CET é propiciada por contato diário com peixes e com o rio desde criança, bem como por observação das práticas de pesca em grupo. O CET é parte da identidade e representa uma herança cultural que deve ser valorizada. É necessária a participação desses atores sociais nos planos de decisão e de gerenciamento de áreas protegidas.