Structure and floristic diversity of woody plants of the Tamaulipas Thornscrub in an ecological reserve in northeast Mexico

Abstract

The Tamaulipas thorn scrub in northeastern Mexico is one of the ecosystems most degraded by human action. One of the measuresimplemented for its protection is the declaration of the creation of ecological reserves, which are areas destined for the conservationof ecosystems and what is found in them. This study seeks to know if the sites of the ecological reserve that have been reforestedwill present a lower abundance of individuals, cover, basal area and volume of wood than the rest of the reserve. Stratified randomsampling was carried out to determine the structure and diversity of the vegetation. 10 strata (sites) were established, where siteswith rectangular plots of 10 m × 20 m were established. Woody individuals with a basal diameter> 3 cm were evaluated in eachplot and the total height, basal diameter and crown diameter were measured. In the data analysis for each site, the basal area,canopy cover, timber volume and diversity were calculated, with these values an analysis of variance (ANOVA), WinTWINScluster analysis was performed and the vertical distribution index of species was determined. (A). Variables such as basal area,coverage, volume, diversity were determined, in addition to a WinTWINS cluster analysis, analysis of variance (ANOVA) as wellas the vertical distribution index of species (A). The mesquite-huizache site presented the highest basal area values; the ash scrub 2presented the highest coverage, while the vegetation in a site reforested six years ago, presented greater basal area and timbervolume than mature scrub and ash scrub sites. Four groups are distinguished in the TWINSPAN classification. The verticaldistribution registers two strata where a high proportion of species is found. The hypothesis is accepted, since the sites presentdifferences in their structure and diversity, being the reforested sites with 2 and 4 years those that presented the lowest abundanceof individuals, cover, basal area and timber volume.