Changes in Structure and Diversity of Woody Plants in a Secondary Mixed Pine-Oak Forest in the Sierra Madre del Sur of Mexico

Abstract

Abstract:The biotic province of the Sierra Madre del Sur presents a mosaic of woodlands at different successional stages due to frequent modifications in land use. In this study, we analyzed changes in woody flora across three successional stages of pine-oak forest: early, intermediate, and mature. Vegetation composition and diversity were characterized in 10 plots (each 0.28 ha). The mature stage had the highest values for species richness, abundance, and diversity. Pioneer plants were dominant in the early-successional site and may promote the establishment of late-successional species. The vegetation structure was more complex in the mature stage, where members of the Quercus genus were co-dominant with Pinus species. Pine tree richness was highest in the early-successional stage, and its abundance increased at the intermediate-successional site. These results suggest that Pinus species can grow in perturbed and sunny environments but also require favorable edaphic and microclimatic conditions, such as those found in intermediate woodlands. Results of this fieldwork support the initial floristic composition succession model, which suggests that species present at early stages will also occur in subsequent stages. Ecological succession may be considered to be a natural restoration process, and thus, conservation strategies should focus on maintaining distinct successional communities in addition to mature forests in order to preserve a high number of species.

Assessment of Land Use-Cover Changes and Successional Stages of Vegetation in the Natural Protected Area Altas Cumbres, Northeastern Mexico, Using Landsat Satellite Imagery

“…In contrast, the remnants of these forests in 2015 are native areas that have remained unchanged since at least 1973, and the small proportion of this type of vegetation in a given successional stage contributes to an increase in species richness, since it has been observed that the presence of temperate plant communities with different succession times favors regeneration and allows for diversity [77]. Moreover, the spatial distribution of Temperate forests, both native areas and those with a successional process, was mostly concentrated in the northwestern part of the NPAAC, and agrees with the most recent categorization proposed in the official management plan for the study area [42], where the same region is recommended as an area for preservation and restoration of the oak-pine forest.…”

“…In this regard, evidence shows that abandonment of cultivated areas and pasture fields results in the development of thorny vegetation [75], this being one of the communities considered within the Scrub vegetation in our study. In Mexico, it has been observed that early succession stages are characterized by a dominance of herbaceous and shrubs for both Tropical vegetation [76] and Temperate forests [77]. In addition, scrub vegetation exists as an ecotone with areas of these two vegetal communities [78].…”

Relationship Between Bird Diversity and Habitat along a Pine- Oak Successional Forest in Southern Mexico

“…With this data, we evaluated the foliage height diversity (FHD) using the Shannon-Wiener index. Detailed vegetation analyses for these sites are described in Almazán-Núñez et al [7].…”

“…In temperate forest ecosystems of Mexico and other parts of the world, many anthropogenic activities (i.e., agriculture, overharvesting, and fires) have increasingly modified the composition and structural characteristics of vegetation [5,6]. As a consequence, many of these landscapes are currently characterized by secondary forest intermixed with scrublands, grasslands, and farmlands [7]. In these landscapes, vegetation in later successional stages is usually taller and has greater biomass, higher number of vertical structural components, and higher number of tree species [7,8].…”

“…As a consequence, many of these landscapes are currently characterized by secondary forest intermixed with scrublands, grasslands, and farmlands [7]. In these landscapes, vegetation in later successional stages is usually taller and has greater biomass, higher number of vertical structural components, and higher number of tree species [7,8]. Due to their complexity, these habitats often provide a variety of food and nesting sites for specialist birds, in particular [3,9].…”