Abstract Aims Although tropical dry forests are among the most degraded and fragmented biomes in the world, we still only have a poor understanding of their basic ecological features and conservation status, particularly in the Neotropics. Here, we assess the diversity, composition, structure, and conservation value of tropical dry forests in a highly fragmented landscape in Nicaragua. Methods We established 31 plots and transects in and along river corridors, secondary forests, living fences, and pasture-woodlands. We recorded all trees with diameters at breast height ≥ 2.5 cm using Hill numbers ( qD, where q = 0, 1, or 2) and estimated the richness and diversity of trees in each forest type. We calculated the Importance Value Index (IVI) to species and family levels and, finally, performed a Non-Metric Multidimensional Scaling (NMDS) ordination and an Analysis of Similarities (ANOSIM) using the Bray-Curtis index of similarity. Important Findings Diversity ( 1D, 2D) but not species richness ( 0D) differed between forest types (P = 0.01 and 0.66, respectively). The Importance Value Index (IVI) was highest for the legume family Fabaceae, followed by the Moraceae and Malvaceae (27.8, 11.1, and 10.5, respectively). Vachellia pennatula, Guazuma ulmifolia, and Bursera simaruba had IVIs >30%, the former two being the most abundant trees in all forest types. An analysis of community similarity found that each forest type had a distinct composition (P < 0.01, R2 = 0.30), thereby underlining the importance of conserving all these different types of land cover.

中文翻译：

---

高度碎片化景观中热带干旱森林的结构、多样性和保护价值

摘要 目的尽管热带干旱森林是世界上退化和破碎最严重的生物群落之一，但我们对其基本生态特征和保护状况仍然知之甚少，尤其是在新热带地区。在这里，我们评估了尼加拉瓜高度分散的景观中热带干旱森林的多样性、组成、结构和保护价值。方法在河道、次生林、生活围栏和草场林地及其沿线建立31个样地和样带。我们使用希尔数（qD，其中 q = 0、1 或 2）记录了胸高 ≥ 2.5 cm 的所有树木，并估计了每种森林类型中树木的丰富度和多样性。我们计算了物种和科级别的重要性值指数 (IVI)，最后，使用 Bray-Curtis 相似性指数进行了非度量多维尺度 (NMDS) 排序和相似性分析 (ANOSIM)。重要发现 森林类型之间的多样性（1D、2D）而非物种丰富度（0D）不同（分别为 P = 0.01 和 0.66）。豆科豆科豆科的重要性值指数 (IVI) 最高，其次是桑科和锦葵科（分别为 27.8、11.1 和 10.5）。Vachlia pennatula、Guazuma ulmifolia 和 Bursera simaruba 的 IVIs > 30%，前两者是所有森林类型中最丰富的树木。对群落相似性的分析发现，每种森林类型都有不同的组成（P < 0.01，R2 = 0.