Abstract The Bacalar Lagoon (BL) in Quintana Roo, Mexico; is an area of high interest due to its tourist potential. However, the changes in landuse patterns, urbanization, extensive cattle ranching and rapidly expanding agriculture, have generated negative impacts on areas of adjacent plan communities and wildlife habitats. The objective of this study has to evaluate the level of vegetation conservation in the southern portion of the BL through the avifauna present in sites with contrasting degrees of conservation. Additionally, change “and their habitat preference(s) in the different communities” to and their habitat use preferences in the different communities. To evaluate the level of conservation of the BL, field visits and botanical collections were carried out to identify species. For the counting and identification of birds, monthly surveys were made through coastal tours along the cenote Xul-ha in 2.5 km transects. Four transects were established: two for sites characterized as semi-conserved and two with disturbed sites. A total richness of 40 taxa was observed, which corresponds to 8.1% of the Quintana Roo avifauna and 32% to wetland birds (125 species). The species accumulation curves indicated that semi-conserved and disturbed sites tend to reach asymptotes and with a coverage percentage greater than 90%. In terms of diversity and community structure, no significant differences were observed. However, the semi-conserved and disturbed sites each have 11 unique species and share 18 species. The LB has an intermediate diversity of bird species compared to studies at the Mexican level, the habitat is important for the conservation of birdlife; as it functions as a reservoir of diversity. Strategies has been suggested that promote sustainable tourism, support the restoration of natural vegetation; and facilitate the economic development of the region.

Resumo A Lagoa Bacalar (BL) em Quintana Roo, México, é uma zona de grande interesse devido ao seu potencial turístico. No entanto, as mudanças nos padrões de uso da terra, urbanização, pecuária extensiva e agricultura em rápida expansão geraram impactos negativos nas áreas das comunidades adjacentes do plano e nos habitats da vida selvagem. O objetivo deste estudo foi avaliar o nível de conservação da vegetação na porção sul da BL através da avifauna presente em locais com graus de conservação contrastantes. Além disso, alterar sua(s) preferência(s) de habitat nas diferentes comunidades. Para avaliar o nível de conservação da LB foram realizadas visitas de campo e coletas botânicas para identificação de espécies. Para a contagem e identificação das aves foram realizados levantamentos mensais através de passeios costeiros ao longo do cenote Xul-ha em transectos de 2,5 km. Foram estabelecidos quatro transectos: 2 para locais caracterizados como semiconservados e 2 para locais perturbados. Uma riqueza total de 40 táxons foi observada, o que corresponde a 8,1% da avifauna de Quintana Roo e 32% de aves pantanosas (125 espécies). As curvas de acumulação de espécies indicaram que locais semiconservados e perturbados tendem a atingir assíntotas e com percentual de cobertura superior a 90%. Em termos de diversidade e estrutura comunitária, não foram observadas diferenças significativas. No entanto, os locais semiconservados e perturbados têm, cada um, 11 espécies únicas e partilham 18 espécies. A BL possui uma diversidade intermediária de espécies de aves em comparação com estudos mexicanos, o habitat é importante para a conservação da avifauna; pois funciona como um reservatório de diversidade. Estratégias que promovem o turismo sustentável, apoiam a restauração da vegetação natural e facilitam o desenvolvimento econômico da região foram sugeridas, no presente estudo.

Abstract: The agricultural production systems (APS) in the Yucatan Peninsula (YP) have been analyzed with intentions to their agroforestry transformation. However, the resources for designing agroforestry from a perspective of integration to the natural vegetation (NV) with the APS and to take advantage of the potential of regeneration capacity of most of the native species. The objective is design and characterize the APS and the VN according to the natural resources in the YP, in the community of Pomuch, Campeche, Mexico. Information was collected through interviews with 54 farmers and visits to the APS to identify productive activities. In the areas with NV, 24 temporary circular sites of 500 m2 was established. The APS were identified: forestry and fruit plantation, livestock, and agriculture (mechanized, semi-mechanized, and slash and burn) and home gardens. In areas with NV, 45 tree species were identified, dominant species were: Lysiloma latisiliquum, Bursera simaruba and Piscidia piscipula. Considering production systems characteristics, alternatives to incorporate trees in the APS were proposed. Agroforestry plot-level proposals, seek to achieve connectivity between the APS and NV, through the creation of connectors for tree vegetation that generate a less fragmented and interconnected landscape by including trees in corn monocultures, in and around the paddocks, as well as in transition zones between agricultural areas and natural vegetation, using tree species native to the region such as L. latisiliquum, B. simaruba, P. piscipula and Platymiscium yucatanum.

Resumen: Los sistemas de producción agropecuarios (SPA) en la Península de Yucatán se han analizado con intenciones a su transformación agroforestal. Sin embargo, son escasos los intentos por diseñar sistemas agroforestales desde una perspectiva de integrar a la vegetación natural (VN) con los SPA y de aprovechar el potencial de capacidad de rebrote de la mayoría de las especies nativas. El objetivo del presente estudio fue caracterizar los sistemas de producción agrícola y la vegetación natural, y proponer diseños agroforestales con base en dicha caracterización en la comunidad de Pomuch, Campeche, México. Se entrevistaron a 54 productores y se visitaron los SPA para identificar las actividades realizadas en cada parcela. En áreas con VN se establecieron 24 sitios circulares de 500 m2. Se identificaron los SPA: plantación forestal y frutícola, ganadería, y agricultura (mecanizada, semi-mecanizada y de roza, tumba y quema) y huertos familiares. En áreas con VN se identificaron 45 especies arbóreas, siendo dominantes: Lysiloma latisiliquum, Bursera simaruba y Piscidia piscipula. Se proponen alternativas que incorporan el componente arbóreo, considerando las características de los SPA. Propuestas agroforestales a nivel de parcela buscan favorecer la conectividad entre los SPA y la VN, a través de la creación de conectores de vegetación arbórea que generen un paisaje menos fragmentado e interconectado al incluir árboles en los monocultivos de maíz, dentro y alrededor de los potreros, así como en zonas de transición entre las zonas agropecuarias y la VN, utilizando especies arbóreas nativas de la región como L. latisiliquum, B. simaruba, P. piscipula y Platymiscium yucatanum.

ABSTRACT: The Yucatan Peninsula as biogeographic province consists of the Mexican states of Campeche, Quintana Roo, and Yucatan, a more natural area also includes the northern regions of Belize, and Guatemala, and it is known as the Yucatan Peninsula Biotic Province. This province has karst geology, low surface hydrography, elevations below 350 meters, and a gradient of precipitation that allows the formation of different plant associations and the deciduous forest, semideciduous forest, and the evergreen forest are the most commons ones. The floristic information of this region is constantly updated. In the present work, this process is exemplified through an update for the endemic vascular flora and the recognition of new records from the last floristic checklist of the Mexican Yucatan Peninsula (Carnevali et al., 2010). Likewise, the application of a density index of botanical collection (IDCB, number of botanical collections /area) has been proposed, as a tool to evaluate the state of floristic knowledge by country, state or other administrative political unit. For example, a previous estimation for the Yucatan state yielded an index of 159 samples/km2. This parameter was calculated for the entire region and the three states. In general, the floristic knowledge of the region is still in progress (new species, and new records), the state best collected is Yucatan, followed by Quintana Roo and Campeche. These last two states require more botanical collections, especially outside the area of influence of roads and populated centers.

RESUMEN: La Península de Yucatán está conformada de los estados mexicanos de Campeche, Quintana Roo y Yucatán; un área más natural incluye también las regiones septentrionales de Belice y Guatemala y se conoce como Provincia Biótica Península de Yucatán. La Península de Yucatán posee una geología cárstica, una hidrografía superficial escasa, elevaciones menores de 350 metros y un gradiente de precipitación que permite la formación de diferentes asociaciones vegetales, siendo las selvas caducifolias, subcaducifolias y perennifolias las más predominantes. La información florística de esta región se actualiza constantemente y en el presente trabajo, se demuestra dicha proceso a través de una actualización de la flora vascular endémica y de la recopilación de nuevos registros partiendo del último listado florístico de la Península de Yucatán mexicana (Carnevali et al., 2010). Asimismo se ha propuesto la aplicación de un índice de densidad de colección botánica (IDCB, número de colecciones botánicas/área km2), como herramienta para evaluar el estado de conocimiento florístico por país, estado u otra unidad política administrativa. Por ejemplo, una estimación previa para el estado de Yucatán arrojó un índice de 159 muestras/km2. Se calculó este parámetro para toda la región y para los tres estados. En general el conocimiento florístico de la región sigue en marcha con la descripción de nuevas especies para la ciencia cuyo material botánico es originario de la región y la adición de nuevos registros florísticos. El estado mejor conocido es Yucatán, seguido de Quintana Roo y Campeche. Estos dos últimos estados requieren más colecciones botánicas, en especial fuera del área de influencia de carreteras y centros poblados.