Domesticated Landscapes in Araucaria Forests, Southern Brazil: A Multispecies Local Conservation-by-Use System

Abstract

Araucaria forest is a sub-tropical component of the Atlantic Forest Biome, occurring between 18 and 30 • S latitude, and 500-1,800 m altitude in Southern and Southwestern Brazil and Northwestern Argentina. In recent history (Twentieth century), this forest has undergone non-sustainable exploitation and reduction in area dedicated to agricultural and forestry use. However, smallholders continue using several resources from this forest, even adapting management systems. The main system is geared toward the production of yerba mate (Ilex paraguariensis) under araucaria trees (Araucaria angustifolia), which holds economic, cultural, and social relevance for thousands of farmers. Seeking evidence of domestication and conservation of the resources managed in this system, we compared different landscapes on the Northern Plateau of Santa Catarina in Southern Brazil. Focusing on three species-yerba mate, araucaria and caraguatá (Bromelia antiacantha)-we characterized management practices (interviews and guided tours), demographic structure (permanent plots in farming zones and in a protected area), and genetic diversity in populations from the same places. Demographic structure and genetic diversity from different landscapes were compared to evaluate the system potential for conservation. The results indicated that the three species are intentionally promoted with practices of protection, transplanting and/or selection, in different ways and with different functions (caraguatá hedges, yerba mate harvesting, and collection of pinhões-seed like nuts-of araucaria). Landscapes are managed for yerba mate harvesting and cattle raising, for both economic and cultural reasons, with a consequent reduction in the density of most other plant species. In all cases the genetic diversity of the species was high for most of the sampled properties, and the set of farmers' populations did not differ from the protected area. The set of populations of each species operates as a metapopulation and local management practices contribute to conservation. Thus, the farmers' management systems and practices maintain the Reis et al.Conservation-by-Use System in Araucaria Forests landscape with productive forest fragments, favoring the conservation-by-use of these species. The system requires these management practices, which bring about changes in various species and are motivated by cultural and economic factors, in order to maintain the landscapes domesticated.

Cold spot microrefugia hold the key to survival for Brazil's Critically Endangered Araucaria tree

“…This could take the form of reforestation in resilient areas (though whether other key MOF species would have similar preferred areas in the future is uncertain), or the good stewardship of semi‐natural landscapes in these areas. Some such areas, traditionally managed for cattle or nontimber forest products, can conserve Araucaria's genetic diversity as effectively as protected areas while also providing economic incentives to retain the trees (Medina‐Macedo et al, ; Reis et al, ; Zechini et al, ), so their inclusion in conservation planning is likely to improve Araucaria's climate resilience. However, the legal restrictions on felling mature Araucaria trees (and on land use changes in areas containing them) have led some land owners to actively prevent Araucaria's natural regeneration by removing its seedlings from their properties (Adan et al, ; Mello & Peroni, ; Vibrans et al, ); addressing this issue is critical in order for private lands to contribute effectively to the species' long‐term conservation.…”

Cattle influence on the population structure of yerba mate (Ilex paraguariensis) in Araucaria Forest

“…which negatively influence species development, affect the presence of dispersing agents, seasonality and propagule production. In a study that was developed in different landscape units of I. paraguariensis yerba management and cattle grazing, yerba management and no cattle grazing and no management, REIS et al (2018) observed demographic peculiarities between and within the evaluated landscape in the PNC. It is also worth mentioning that microhabitat characteristics can influence the development of individuals that make up a population (RODE et al, 2010), and according to AVILA et al (2016), I. paraguariensis can present a differentiated population structure within the same environment, as well as in the different sampled areas.…”

“…Ilex paraguariensis A.St.-Hil (yerba mate) is the most relevant species of its kind from an economic perspective, and it presents a high sociocultural importance for the southern region of Brazil (REIS et al, 2018). It is well known and exploited for its stimulant drink and also for formulating drugs and cosmetics.…”

“…Leaves and branches of I. paraguariensis in the Atlantic Forest constitute an important Non-Wood Forest Product (NWFP) from forest extraction (REIS et al, 2018). High exploitation rates occurring in natural areas due to economic instability have caused a significant decline in its populations (SMALL & CATLING, 2011).…”

“…Understanding demographic aspects such as height and diameter distribution, density, mortality, recruitment of individuals, the number of reproductive indices and their life cycle (e.g. longevity) can help provide more knowledge on its dynamics in natural populations which are considered basic premises to develop management and conservation strategies (REIS et al, 2018;MONTAGNA et al, 2018). Studies indicated that dispersal and recruitment may be considered determinant for the spatial pattern of plants.…”