Groundwater is a critical water source in the semi-arid West Liao River Basin (WLRB). Based on daily observations from 117 monitoring wells distributed across the basin during 2019–2024, this study analyzed interannual and seasonal groundwater-level dynamics and identified areas of relative groundwater stress using groundwater level elevation (WLE) and depth to water (DTW). The Mann–Kendall test, Sen’s slope estimator, ordinary kriging, and a composite risk index were applied to quantify temporal trends, map spatial patterns, and classify groundwater risk. Regional WLE showed weak interannual variability but a distinct seasonal cycle, with positive anomalies from January to April and negative anomalies from June to September. At the well scale, 51 wells (43.59%) exhibited significant increases, whereas 36 wells (30.77%) showed significant decreases. Sen’s slope ranged from −2.75 to 0.61 m/year, indicating that the strongest local changes were associated with groundwater-level decline. Spatially, WLE was generally higher in the southwest and lower toward the northeast. Areas with WLE decline were concentrated in the central-western and southern sectors, whereas relative WLE increases occurred in parts of the northern and eastern sectors. The low-, medium-, and high-risk classes included 39, 38, and 39 wells, accounting for 33.62%, 32.76%, and 33.62% of the wells retained for the risk assessment, respectively. High-risk wells clustered in the central-western and southern areas, while low-risk wells dominated the northern and eastern sectors. These results highlight the importance of well-scale monitoring for identifying priority areas of groundwater stress. The proposed framework provides a practical basis for screening priority monitoring areas and supporting spatially differentiated groundwater management in semi-arid basins. However, this study is limited by the relatively short monitoring period (2019–2024) and the lack of quantitative driver attribution; therefore, the findings reflect recent groundwater dynamics rather than long-term secular trends.

Seasonal dynamics in wetland landscapes are closely associated with habitat availability and are likely to influence the spatial organization and diversity of waterbird communities. However, most existing studies rely on static land-cover representations or single spatial scales, limiting our ability to characterize how waterbirds respond to seasonally shifting habitats across scales. Focusing on the Qilihai Wetland in Tianjin, China, we combined high-frequency waterbird surveys from 2019–2021 with multi-temporal, season-matched Sentinel-2 imagery and the Dynamic World dataset. Partial least squares regression (PLSR) was applied across a continuous spatial gradient (100–3000 m) to quantify scale-dependent statistical associations between landscape composition and configuration derived from satellite-mapped habitat mosaics on different functional groups. Waterbird diversity exhibited pronounced seasonal contrasts. During the breeding and post-fledging period, high-diversity assemblages were stably concentrated within core wetland areas, showing limited spatial variability. In contrast, during the wintering and stopover period, community distributions became increasingly dispersed, with elevated spatial heterogeneity and interannual variability associated with habitat reorganization. The scale of effect shifted systematically between seasons. In the breeding and post-fledging period, both waterfowl and waders responded predominantly to local-scale landscape factors (<800 m), consistent with nesting requirements and microhabitat conditions. During the wintering and stopover period, however, the characteristic response scale of waterfowl expanded to 1500–2000 m, suggesting stronger associations with broader landscape context, whereas waders remained closely linked to local-scale shallow-water and mudflat connectivity (~200 m). Functional traits played a key role in structuring these scale-dependent responses, with diving behavior and tarsus length being associated with strong constraints on habitat use. Overall, our results suggest that waterbird diversity patterns emerge from the interaction between seasonal habitat dynamics, landscape structure, and functional trait filtering, underscoring the need for phenology-informed, multi-scale conservation strategies that move beyond static spatial boundaries.