Table_1_Mediterranean university campuses enhance butterfly (Lepidoptera) and beetle (Coleoptera) diversity.DOCX

Human population growth is causing an expansion of urban areas, a phenomenon known to deeply impact on the Earth’s biodiversity. Therefore, it is key to understand how to conceal urban development with biodiversity conservation. In this context, university campuses can play an important role as they usually present a large array of different environments and green areas, crucial aspects for promoting urban biodiversity as well as human-nature interactions. Several studies have analyzed the biodiversity of university campuses, however, there are still important taxonomic (e.g., insects) and geographical biases (e.g., Mediterranean hotspot) in our current understanding of these urban areas. Insects are fundamental in many ecosystems as pollinators, prey, pest controllers or decomposers among others. This further increases the need to study this group in the urban context. In this study, we have investigated diurnal Lepidoptera and ground-dwelling Coleoptera in three university campuses and three non-campus areas of the city of Granada (Spain). We used spatial and temporal replicates for each area in order to explore whether university campuses hold higher levels of insect biodiversity (e.g., species richness or common species) than other nearby urban areas. In addition, we investigated the potential influence of several additional predictors on insect diversity such as type of land cover, vegetation origin, management intensity, and distance to the outskirts. Our results suggest that Lepidoptera species and Coleoptera families are more diverse in university campuses than in other urban areas, showing also a positive association with the proportion of bare soil and herbaceous cover. Furthermore, they also seem to be benefited from low vegetation management intensity whereas Coleoptera are favored by native vegetation providing clear management recommendations in order to promote such animal groups in cities. Our study indicates that university campuses are important urban areas to preserve insect biodiversity but also highlights the heterogeneity of response among insect groups.

人口增长推动城市用地规模持续扩张，该现象已被证实会对地球生物多样性造成深远负面影响。因此，探明如何协调城市开发与生物多样性保护的关系，是当前的核心议题。在此背景下，大学校园可发挥重要作用：这类区域通常拥有丰富多样的生境与绿地资源，是推动城市生物多样性保护及促进人与自然互动的核心要素。已有多项研究针对大学校园的生物多样性展开分析，但当前学界对这类城市区域的认知仍存在显著的分类学（如昆虫类群）与地理（如地中海生物多样性热点区域）偏差。昆虫作为传粉者、猎物、害虫天敌或分解者等，在众多生态系统中发挥着基础性生态功能，这进一步凸显了在城市环境中开展昆虫类群研究的必要性。本研究以西班牙格拉纳达市的3处大学校园与3处非校园城市区域为研究对象，对日间活动的鳞翅目（Lepidoptera）昆虫与地表栖居的鞘翅目（Coleoptera）昆虫开展了调查。我们为每个研究区域设置了空间与时间重复样地，旨在探究大学校园的昆虫生物多样性水平（如物种丰富度或常见物种占比）是否高于周边其他城市区域。此外，本研究还探讨了多项额外预测因子对昆虫多样性的潜在影响，包括土地覆盖类型、植被起源、管理强度以及距城市边缘的距离。研究结果显示，大学校园内的鳞翅目物种丰富度与鞘翅目科类丰富度均高于其他城市区域，且与裸土及草本覆盖比例呈显著正相关关系。进一步分析表明，低强度植被管理对两类昆虫类群均具有积极作用，而本土植被更利于鞘翅目生存，该结果可为城市中促进这类动物类群的保护提供明确的管理建议。本研究证实，大学校园是保护城市昆虫生物多样性的重要城市区域，同时也凸显了不同昆虫类群对城市环境响应的异质性。