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Abandonment of agricultural lands promotes the global expansion of secondary forests, which are critical for preserving biodiversity and ecosystem functions and services. Such roles largely depend, however, on two essential successional attributes, trajectory and recovery rate, which are expected to depend on landscape-scale forest cover in nonlinear ways. Using a multi-scale approach and a large vegetation dataset (843 plots, 3511 tree species) from 22 secondary forest chronosequences distributed across the Neotropics, we show that successional trajectories of woody plant species richness, stem density and basal area are less predictable in landscapes (4 km radius) with intermediate (40–60%) forest cover than in landscapes with high (greater than 60%) forest cover. This supports theory suggesting that high spatial and environmental heterogeneity in intermediately deforested landscapes can increase the variation of key ecological factors for forest recovery (e.g. seed dispersal and seedling recruitment), increasing the uncertainty of successional trajectories. Regarding the recovery rate, only species richness is positively related to forest cover in relatively small (1 km radius) landscapes. These findings highlight the importance of using a spatially explicit landscape approach in restoration initiatives and suggest that these initiatives can be more effective in more forested landscapes, especially if implemented across spatial extents of 1–4 km radius.

The Mesoamerican gene pool of wild lima bean (Phaseolus lunatus L., Fabaceae) is an important source of genes for genetic improvement of the species. Is widely distributed from northern Mexico to northern Argentina. Reports in Mexico indicate that this gene pool is distributed from Sinaloa to Chiapas on the Pacific Coast and southern Tamaulipas to the Yucatan Peninsula on the Coast of Gulf of Mexico, as well as, in the Isthmus of Tehuantepec. However, despite the knowledge we have about the distribution of this gene pool, in Mexico there are still collecting gaps and unexplored regions. The objective of this study was to collect wild populations of lima bean in Mexico to know its current distribution and establish management and conservation strategies. To do this, we collected within the natural distribution range of the Mesoamerican gene pool of lima bean in Mexico, with the passport data was designed a geographical distribution map and assessed the conservation status of populations. Results indicated that wild populations of lima bean have a wide geographical distribution localized mainly in tropical deciduous forest and semideciduous and elevations from zero to 2 292 meters. In most wild population collected a low conservation status was observed, in consequence was proposed the development of strategies for in situ and ex situ conservation for wild populations with higher degree of erosion., Resumen: El acervo genético mesoamericano del frijol lima silvestre (Phaseolus lunatus L., Fabaceae) representa una fuente importante de genes para el mejoramiento genético de la especie. Presenta una amplia distribución geográfica que abarca del norte de México al norte de Argentina. En México los reportes muestran que este acervo se distribuye de Sinaloa hasta la región de Chiapas, por la costa del Pacífico y del sur de Tamaulipas hasta la Península de Yucatán por la Costa del Golfo de México, así como también en la región del Istmo de Tehuantepec. Sin embargo, a pesar del conocimiento que se tiene sobre la distribución de este acervo, en México aún existen regiones con vacíos de colecta para P. lunatus. El objetivo del presente trabajo consistió en realizar colectas de poblaciones silvestres del frijol lima en México, para conocer su distribución actual y establecer estrategias de manejo y conservación. Para ello, se realizaron colectas dentro del área de distribución natural del acervo genético mesoamericano del frijol lima en México, se diseño un mapa de distribución geográfica con los datos de pasaporte y se analizó el estado de conservación de las poblaciones. Los resultados demostraron que las poblaciones silvestres del frijol lima, presentan una amplia distribución geográfica localizándose principalmente en zonas de selva tropical caducifolia y subcaducifolia con altitudes de cero a 2 292 metros. Se observó un bajo estado de conservación en la mayoría de las poblaciones silvestres colectadas, en consecuencia, se propuso el desarrollo de estrategias de conservación in situ y ex situ para las poblaciones silvestres con mayor grado de erosión.