Temporal and Spatial Distribution of Nitrogen Distribution in Agricultural Typical Watershed in Jiaodong Peninsula
Yantai City is located in the northern part of Jiaodong Peninsula,the total nitrogen concentration is much higher in Menlou Reservoir,which is the city's drinking water source.In order to explore the nitrogen distribution characteristics and temporal and spatial changes in Qingyang River upstream of Menlou Reservoir,optimize and formulate nitrogen control mea-sures,and monitoring and analysis of nitrogen concentration were done in the water bodies of Qingyang River.The results show that the TN concentration was relatively high,ranging from 6.37 to 53.3 mg/L.In 2023,the average in dry season was 36.8 mg/L,the average in normal season was 21.6 mg/L,and the average in wet season was 15.9 mg/L.The concentration shows a changing pattern of dry season>normal season>wet season,with the concentration in the main stream being higher than the tributaries;the main form of nitrogen in Qingyang River was NO3--N,accounting for 90.8%of the TN concentration;the nitrogen high value area mainly distributed in areas where apples planting was concentrated,the average value of chemi-cal fertilizers converted to pure nitrogen for apples planting was 483.2 kg/(hm2·a);the changing patterns of physical and chem-ical factors in the water bodies show that the nitrogen content had always been maintained at a high level,source input and en-dogenous release affected the regional nitrogen content.
nitrogen formtemporal and spatial distributioncorrelation analysisQingyang River