title: Agroforestry systems of the lowland alluvial valleys of the Tehuacán-Cuicatlán Biosphere Reserve: an evaluation of their biocultural capacity.
abstract: BACKGROUND
  Agroforestry systems (AFS) are valuable production systems that allow concealing benefits provision with conservation of biodiversity and ecosystem services. We analysed AFS of the zone of alluvial valleys of the Tehuacán-Cuicatlán Valley (TCV), Mexico, the most intensive agricultural systems within a region recognized for harbouring one of the most ancient agricultural experience of the New World. We hypothesized that the biodiversity conservation capacity of AFS would be directly related to traditional agricultural features and inversely related to management intensity.
  
  
  METHODS
  Agricultural practices, use frequency of machinery and chemical inputs, and proportion of forest and cultivated areas were described in 15 AFS plots in alluvial valleys of the Salado River in three villages of the region. With the information, we constructed a management intensity index and compared among plots and villages. We documented the reasons why people maintain wild plant species and traditional practices. Perennial plant species were sampled in vegetation of AFS (15 plots) and unmanaged forests (12 plots 500 m(2)) in order to compare richness, diversity and other ecological indicators in AFS and forest.
  
  
  RESULTS
  In all studied sites, people combine traditional and intensive agricultural practices. Main agroforestry practices are ground terraces and borders surrounding AFS plots where people maintain vegetation. According to people, the reasons for maintaining shrubs and trees in AFS were in order of importance are: Beauty and shade provision (14% of people), fruit provision (7%), protection against strong wind, and favouring water and soil retention. We recorded 66 species of trees and shrubs in the AFS studied, 81% of them being native species that represent 38% of the perennial plant species recorded in forests sampled. Land tenure and institutions vary among sites but not influenced the actions for maintaining the vegetation cover in AFS. Plant diversity decreased with increasing agricultural intensity.
  
  
  CONCLUSIONS
  Maintenance of vegetation cover did not confront markedly with the intensive agricultural practices. It is possible the expansion and enrichment of vegetation in terraces and borders of AFS. Information available on plant species and local techniques is potentially useful for a regional program of biodiversity conservation considering AFS as keystones.
authors.affiliation: Centro de Investigaciones en Ecosistemas, UNAM campus Morelia, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, Mexico. mvallejo@cieco.unam.mx.
authors.forename: Mariana
authors.initials: M
authors.lastname: Vallejo
authors.affiliation: Centro de Investigaciones en Ecosistemas, UNAM campus Morelia, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, Mexico. acasas@cieco.unam.mx.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Casas
authors.affiliation: Centro de Investigaciones en Ecosistemas, UNAM campus Morelia, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, Mexico. epnegron@cieco.unam.mx.
authors.forename: Edgar
authors.initials: E
authors.lastname: Pérez-Negrón
authors.affiliation: Escuela Nacional de Estudios Superiores Unidad Morelia, UNAM campus Morelia, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, Mexico. nakaricitla@gmail.com.
authors.forename: Ana I
authors.initials: AI
authors.lastname: Moreno-Calles
authors.affiliation: Centro de Investigaciones en Ecosistemas, UNAM campus Morelia, Antigua Carretera a Pátzcuaro No. 8701, Col. Ex-Hacienda de San José de la Huerta, Morelia, 58190, Michoacán, Mexico. omar_ho@cieco.unam.mx.
authors.forename: Omar
authors.initials: O
authors.lastname: Hernández-Ordoñez
authors.affiliation: UBIPRO, Facultad de Estudios Superiores Iztacala, UNAM, Avenida de los Baños, s/n, Apartado Postal 54090 (Los Reyes Iztacala), Tlalnepantla, Estado de México. tellez@servidor.unam.mx.
authors.forename: Oswaldo
authors.initials: O
authors.lastname: Tellez
authors.affiliation: UBIPRO, Facultad de Estudios Superiores Iztacala, UNAM, Avenida de los Baños, s/n, Apartado Postal 54090 (Los Reyes Iztacala), Tlalnepantla, Estado de México. pdavilaa@unam.mx.
authors.forename: Patricia
authors.initials: P
authors.lastname: Dávila
mesh_terms: D000383:Agriculture; D044822:Biodiversity; D003247:Conservation of Natural Resources; D016468:Forestry; D065928:Forests; D008800:Mexico; D010944:Plants; D014197:Trees