Variability of suspended solids concentration in urban ponds and intervening river sections under the influence of external factors

The article summarizes and analyzes the data of field studies conducted in 2023-2025 on the content of suspended solids (SS) in the water of urban ponds and residual sections of the small river (stream) Horikhuvatka (Orikhovatka) within its outlet in the Holosiivskyi National Park. The correlations between abiotic conditions in the two final sections of the study site were investigated, and spatial and temporal changes in the content of suspended solids in water were analyzed. Spearman’s correlation analysis showed that the amount of suspended solids (rs = 0.47, р< 0.05) and the mineral fraction of suspended solids (rs = 0.69, р< 0.05) increased with distance from the conditional mouth, which is explained by the predominance of sedimentation processes in the shallow water of the ponds, the largest of which are the latter two. At the same time, the supply of allochthones material with surface runoff during intense precipitation reverses the relationship (rs = -0.71 and -0.53, р< 0.05). It has been determined that the amount and composition of the SS is influenced by both natural and anthropogenic factors, namely general climate change, partial urbanization of the catchment, recreational load in the coastal zone, local fragmentation and hydromorphological changes in the water body. The disruption of the river’s continuity through the creation of ponds has led to variable conditions, including a significant difference in the composition of suspended solids and a different response of the indicator to surface runoff. In the future, it is worthwhile to study the anthropogenic transformation of the catchment area and the coastal zone in particular, and their impact on the abiotic and biotic components of the Horikhuvata ecosystem. It is also worth developing and implementing measures to manage the condition of the ponds and the areas between them, taking into account the restrictions imposed by the location within the protected area.