Knowledge about population attributes, current geographic distribution, and changes over predicted climate change for many threatened endemic vascular plants is particularly limited in arid mountain environments. Primula boveana is one of the rarest and threatened plants worldwide, surviving exclusively in Saint Catherine Protectorate in the Sinaic biogeographic subsector of Egypt. This study aimed to define the current state of P. boveana populations, predict its current potential distribution, and use the best-model outputs to guide in field sampling and to forecast its future distribution under two climate change scenarios. The MaxEnt algorithm was used by relating 10 occurrence-points with different environmental predictors (27 bioclimatic, 3 topographic, and 8 edaphic factors). At the current knowledge level, the population size of P. boveana consists of 796 individuals, including 137 matures, distributed in only 250 m². The Canonical Correlation Analysis (CCorA) displayed that population attributes (density, cover, size index, and plant vigor) were positively correlated with elevation, precipitation, and pH. Based on the best-fitting model, most predicted suitable central sites (69 km²) of P. boveana were located in the cool shaded high-elevated middle northern part of St. Catherine. Elevation, precipitation, temperature, and soil pH were the key contributors to P. boveana distribution in Egypt. After field trips in suitable predicted sites, we confirmed five extinct localities where P. boveana has been previously recorded and no new population was found. The projected map showed an upward range shift through the contraction of sites between 1800 and 2000 m and expansion towards high elevation (above 2000 m) at the southern parts of the St. Catherine area. To conserve P. boveana, it is recommended to initiate in situ conservation through reinforcement and reintroduction actions.

中文翻译：

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预测濒危特有维管束植物报春花当前和未来的潜在分布。埃及的前杜比。


在干旱山区环境中，关于许多受威胁的特有维管束植物的种群属性、当前地理分布以及预测气候变化的变化的知识尤其有限。报春花是世界上最稀有和受威胁的植物之一，仅生存在埃及西奈克生物地理分区的圣凯瑟琳保护国。本研究旨在确定P. boveana种群的现状，预测其当前的潜在分布，并使用最佳模型输出来指导现场采样并预测其在两种气候变化情景下的未来分布。 MaxEnt 算法通过将 10 个发生点与不同的环境预测因素（27 个生物气候因素、3 个地形因素和 8 个土壤因素）联系起来。根据目前的知识水平，白杨的种群规模为796个体，其中成熟个体137个体，分布在仅250 m ^{2 的}面积内。典型相关分析（CCorA）显示种群属性（密度、覆盖度、大小指数和植物活力）与海拔、降水量和 pH 值呈正相关。根据最佳拟合模型，预测的最适宜的P. boveana中心位点（69 km ² ）位于圣凯瑟琳中北部阴凉高海拔地区。海拔、降水量、温度和土壤 pH 值是影响埃及P. boveana分布的关键因素。在对合适的预测地点进行实地考察后，我们确认了五个先前曾记录过牛白杨的灭绝地点，但没有发现新的种群。 投影地图显示，在圣凯瑟琳地区南部，1800 至 2000 米之间的地点收缩，并向高海拔（2000 米以上）扩展，范围向上移动。为了保护波韦纳松，建议通过强化和重新引入行动启动就地保护。