Desertification is a phenomenon that takes place in the arid, semiarid and dry subhumid areas of the Planet. Although its causes and consequences are well known, data and robust information are often insufficient to provide indicators that allow desertification effects to be measured precisely and efficiently. Accordingly, the objective of this study was to introduce a methodology for the drafting of a monitoring index for desertification, with indicators of vegetal coverage, taking the semiarid area of Paraiba State, Brazil, as the test example. For this purpose, we analyzed conserved and desertified areas (22 pairs), in which we evaluated the following parameters: woody species richness, woody plant density, canopy height, mean basal circumference, mean circumference at breast height and total absolute dominance. First, we selected the indicators, calculated the areas of coverage and measured the reference values. Subsequently, we obtained masses for the indicators, and developed and tested the desertification degree index (DDI). The DDI showed 99% accuracy and 95% efficiency, respectively, and was able to select indicators and evaluate the level of desertification in the test areas. The methodology is simple, inexpensive and replicable in other regions of the world as a means of monitoring and planning strategies to counter desertification.

中文翻译：

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在巴西半干旱地区监测荒漠化：使用荒漠化程度指数（DDI）

荒漠化是在地球的干旱，半干旱和干燥半湿润地区发生的现象。尽管其成因和后果是众所周知的，但数据和可靠的信息通常不足以提供指标，从而无法准确有效地测量荒漠化的影响。因此，本研究的目的是介绍一种草拟荒漠化监测指标的方法，其中以植物覆盖率指标为例，以巴西帕拉伊巴州的半干旱地区为例。为此，我们分析了保护区和荒漠化地区（22对），在其中评估了以下参数：木本植物物种丰富度，木本植物密度，树冠高度，平均基周长，胸部高度的平均周长和总绝对优势度。第一，我们选择了指标，计算了覆盖范围并测量了参考值。随后，我们获得了质量指标，并开发和测试了沙漠化程度指数（DDI）。DDI分别显示了99％的准确度和95％的效率，并且能够选择指标并评估测试区域的荒漠化程度。该方法简单，廉价且可在世界其他地区复制，作为监测和规划防治荒漠化战略的手段。并能够选择指标并评估测试地区的荒漠化程度。该方法简单，廉价且可在世界其他地区复制，作为监测和规划防治荒漠化战略的手段。并能够选择指标并评估测试地区的荒漠化程度。该方法简单，廉价且可在世界其他地区复制，作为监测和规划防治荒漠化战略的手段。