Can Agriculture Conserve Biodiversity? Structural Biodiversity Analysis in a Case Study of Wild Bird Communities

Agriculture plays a dual role in shaping biodiversity, providing secondary habitats while posing significant threats to ecological systems through habitat fragmentation and land use intensification. This study evaluates the impact of land use types on avian biodiversity in a predominantly agricultural landscape in Apulia, Italy, by analyzing 20 sites fuzzily classified into three ecosystem categories: agricultural (AGR), mixed (MIX) and natural (NAT), according to the percentage of natural cover. Biodiversity indices were calculated for each bird community observed. The abundance curves showed a geometric series pattern for the AGR communities, indicative of ecosystems at an early stage of ecological succession, and a lognormal distribution for the MIX and NAT communities, typical of mature communities with a more even distribution of species. Analysis of variance showed significant differences in richness and diversity between AGR and NAT sites, but not between NAT and MIX, which had the highest values. Logistic regression estimated the probability of sites belonging to the three ecosystem categories as a function of biodiversity, confirming a strong similarity between NAT and MIX. Finally, linear discriminant analysis confirmed a clear separation from AGR areas, as evidenced by the canonical components. The results highlight the importance of integrating high-diversity landscape elements and appropriate agricultural practices to mitigate biodiversity loss. Even a small increase in the naturalness of agricultural land would be sufficient to convert it from AGR to MIX ecosystem category, with significant biodiversity benefits.