BackgroundAlthough the mesquite (mesquital or mezquital in Spanish) is one of the representative ecosystems of the landscapes in the north of Mexico, it is also one of the least studied. This study evaluated the structure (horizontal and vertical) and diversity of a plant community of mesquite in Northeastern Mexico. Three plots of 1,600 m2 each were established. All trees and shrubs with a basal diameter (d0.10) ≥ 0.5 cm were recorded, and total height (h) and crown diameter (dcrown) were measured.ResultsThere were 8 families, 12 genera and 14 species. The genus presenting the most species was Acacia (three species). The most representative family was Fabaceae with seven species. The evaluated community presents a density of 375 N/ha and a crown area of 6,600 m2/ha. The species with the highest values on the Importance Value Index (IVI) were Prosopis glandulosa (15.95%), Acacia amentacea (14.50%), Havardia pallens (14.27%) and Acacia farnesiana (11.22%). These four species account for 55.94% of IVI. The value obtained from the Vertical Species Profile Index (A) was 3.03, with an Amax of 3.74 and an Arel of 81.15%, indicating high structural diversity in the high strata. The evaluated plant community had a Margalef Diversity Index value of DMg = 2.50 and a Shannon Index value of H′ = 2.28, values which are intermediate and considered to be common in the scrublands of Northeastern Mexico.Conclusions1) The studied community presents intermediate values that are considered as common in comparison to other arid and semi-arid vegetation associations of Northeastern Mexico. 2) The abundance curve of the species was well adjusted to the geometric model, and the distribution is associated with adverse environments such as semi-arid. 3) The family with greater importance for its contribution to the community is Fabaceae, while the genus with more species was Acacia. The research generated quantitative information of the plant community of a mesquite which is in a phase of mature ecological succession.

中文翻译：

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Pesquería（墨西哥东北部）豆科植物的组成、结构和多样性

背景虽然豆科灌木（西班牙语中的mesquital或mezquital）是墨西哥北部景观的代表性生态系统之一，但它也是研究最少的生态系统之一。本研究评估了墨西哥东北部豆科植物群落的结构（水平和垂直）和多样性。建立了三个地块，每个地块面积为 1,600 平方米。记录基径(d0.10)≥0.5 cm的乔灌木，测量总高(h)和冠径(dcrown)。结果共8科12属14种。出现最多物种的属是金合欢（三个物种）。最具代表性的科是豆科，共有七种。评估的群落密度为 375 N/ha，树冠面积为 6,600 m2/ha。重要性价值指数 (IVI) 中具有最高值的物种是 Prosopis gearulosa (15.95%)、Acacia amentacea (14.50%)、Havardia pallens (14.27%) 和 Acacia farnesiana (11.22%)。这四个物种占 IVI 的 55.94%。从垂直物种剖面指数 (A) 获得的值为 3.03，Amax 为 3.74，Arel 为 81.15%，表明高地层具有高度的结构多样性。评估的植物群落具有 DMg = 2.50 的 Margalef 多样性指数值和 H' = 2.28 的香农指数值，这些值是中间值，被认为在墨西哥东北部的灌木丛中很常见。结论 1）研究的群落呈现出中间值与墨西哥东北部的其他干旱和半干旱植被协会相比，它们被认为是常见的。2) 物种的丰度曲线与几何模型进行了很好的调整，分布与半干旱等不利环境有关。3）对群落贡献较大的科是豆科，而种类较多的属是相思属。该研究生成了处于成熟生态演替阶段的豆科植物群落的定量信息。