Abstract Land-use change has caused degradation, loss and fragmentation of semi-natural habitats, especially in grassland ecosystems. Today, the remaining habitats are often situated in a matrix of intensively used agricultural land and are therefore more or less isolated from each other. Connectivity, area and quality of habitat patches have been identified as the most important drivers for the persistence of grassland specialists living in metapopulations. However, the relative importance of these factors is still under debate. We used a large-scale, multi-taxon approach to obtain a general pattern which would facilitate conservationists to promote many, instead of one, species. We studied the patch occupancy of 13 grassland specialists belonging to three different insect orders within a Central European landscape with 89 fragments of calcareous grasslands. To disentangle the relative importance of the three metapopulation parameters, generalized linear models (GLM) and variation-partitioning techniques were used. Our study revealed that habitat quality was the most important factor determining the occurrence of specialized species, followed by habitat area. In comparison to habitat connectivity, the variance explained by habitat quality was significantly higher across the studied species. Nevertheless, the persistence of at least six model organisms depended on the degree of habitat connectivity. We conclude that maintaining a high habitat quality on large patches should be the first choice for the conservation of habitat specialist insects in fragmented landscapes. As a secondary measure, conservationists should concentrate on the restoration of relict sites. This increases not only the habitat area, but also contributes to better habitat connectivity.

中文翻译：

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草原专家的补丁占用：栖息地质量比栖息地连通性更重要

摘要 土地利用变化导致半自然生境，尤其是草地生态系统的退化、丧失和破碎化。今天，剩余的栖息地通常位于密集使用的农业用地矩阵中，因此或多或少彼此隔离。栖息地斑块的连通性、面积和质量已被确定为草原专家生活在复合种群中的最重要驱动因素。然而，这些因素的相对重要性仍在争论中。我们使用大规模、多分类单元的方法来获得一个通用模式，这将有助于保护主义者推广许多而不是一个物种。我们研究了中欧景观中属于三个不同昆虫目的 13 名草原专家的斑块占用情况，其中包含 89 个石灰质草原片段。为了解决三个元种群参数的相对重要性，使用了广义线性模型 (GLM) 和变异划分技术。我们的研究表明，栖息地质量是决定特化物种出现的最重要因素，其次是栖息地面积。与栖息地连通性相比，栖息地质量解释的差异在所研究的物种中显着更高。然而，至少六种模式生物的持久性取决于栖息地连通性的程度。我们得出的结论是，在大块斑块上保持高栖息地质量应该是在破碎景观中保护栖息地专家昆虫的首​​选。作为次要措施，保护主义者应集中精力恢复遗址。这不仅增加了栖息地面积，而且有助于更好地连接栖息地。