# The Effect of Land Cover on the Nectar Collection by Honeybee Colonies in Urban and Rural Areas
## 4 Discussion
[38] hypothesise that specific land cover types, notably those associated with transportation infrastructure or industrial areas, may potentially augment the risk of winter colony losses. This finding suggests that the presence of forage resources alone does not fully capture the complexity of landscape effects on honeybees. To illustrate the relationship between landscape structure and nectar yield in a precise manner, third-degree non-linear regressions were performed for each land cover class. These plots, which depict the relationship between the proportion of a given land cover type within a 3 km radius and the annual hive weight gain, corroborate the general conclusions drawn from [PERSON]'s correlation analysis, namely, the absence of strong, consistent linear relationships. Concurrently, these plots unveiled specific non-linear patterns, which might offer variable interpretative value. For shrub-covered areas and coniferous forests, an upward trend was observed at intermediate levels of land cover, which may indicate a beneficial effect of mosaic-like woodland and shrub habitats on forage availability--consistent with previous findings by [PERSON] et al. [34] and [PERSON] et al. [35]. In the case of shrubs, a distinct peak appears within the range of 6-7.5% coverage, suggesting the existence of an optimal proportion of this land cover class that supports high floral diversity (e.g., brambles, wild roses, and goldenrod). In contrast, for agricultural areas and anthropogenic areas, a clear decline in nectar yield was observed at intermediate levels of land cover (approximately 30-40%), which supports earlier conclusions regarding the negative impact of monoculture farming and built-up areas on the balance and sustainability of floral resources [37; 38]. Interestingly, at very high levels of anthropogenic land cover (>50%), the model indicates a renewed increase in yields. This may be attributed to the presence of green infrastructure in densely built urban environments--such as parks, gardens, and rooftop vegetation--which are classified separately but strongly correlated with built-up areas [22]. Furthermore, in urban areas, individual trees, which are not categorised separately, can assume a significant role. The total number of these trees within the flight radius of bees can be substantial. This phenomenon is especially apparent in urban environments, as evidenced by the case study of Warsaw, the largest city where linden trees have been extensively planted. The study found that trees exhibited the most pronounced levels of nectar production because of the heat island effect. The plots for the remaining land cover classes--wetlands, water bodies, and grasslands--show broad confidence intervals and low effect sizes, indicating high uncertainty in the estimates and a relatively weak influence on nectar yield. This may suggest that these land cover types do not directly provide significant forage resources but could enhance nectar availability indirectly through effects on microclimate or the presence of specific nectar-producing plants, such as willows along watercourses. In summary, the relationships between land cover composition and apiary productivity may follow curvilinear patterns, which helps explain the lack of strong linear correlations. Identifying optimal ranges of certain land cover types--such as 6-8% shrub cover or 10-20% coniferous forest--may provide useful insights for both beekeeping practices and spatial planning. The PCA revealed clear differences in landscape structure between urban and rural apiaries; however, these differences did not translate into distinct groups of apiaries with varying nectar yields. The application of clustering methods based on landscape features did not result in the identification of productivity-based classes, thereby suggesting a high degree of flexibility in the way honeybees exploit available resources.