Understanding the Relationship Between Water Quality and Soil Nutrient Dynamics in Qinghai Lake Through Statistical and Regression Models

Lakes are essential ecosystems that play a significant role in water quality and biodiversity, particularly in nutrient cycling. Nitrogen compounds, including ammonium (NH4+), nitrate (NO3-), and nitrite (NO2-), are critical elements in lake ecosystems, influencing productivity and water quality. This study aimed to investigate nitrogen compounds in Qinghai Lake, assess water and soil quality indicators, and evaluate the relationship between nitrogen (N) and phosphorus (P) levels in water and soil. Water samples from 17 locations around the lake and soil samples from nine sites at two depths were analyzed for various parameters. Statistical and regression analyses were performed to explore the correlations between N forms in water and other parameters in water and total P, total N, and pH in soil, as well as their interactions with environmental variables. The mean concentrations of NO3--N, NH4+-N, and NO2--N were 0.0189 mg/L, 0.112 mg/L, and 0.595 mg/L in Qinghai Lake, respectively. The regression models revealed that the total P in water and soil, along with other environmental factors, play crucial roles in regulating N levels. These findings contribute to our understanding of N cycling in high-altitude lakes and provide insight into managing eutrophication risks in Qinghai Lake.