Nutrient pollution of surface waters is a widespread problem, calling for regional assessments of water quality conditions. In this study, we quantified long-term median nutrient concentrations of total nitrogen (TN) and total phosphorus (TP) in streams and rivers of Pennsylvania and explored relationships between stream nutrient concentrations and the land use of their watersheds. Our analysis is based on a synthesis of monitoring data from multiple agencies that included records of nutrient concentrations observed between 2000–2019. Across the state, stream nutrient concentrations observed in predominantly undeveloped areas (e.g., forests, shrubs, and grasslands) have median concentration values of 0.42 mg l⁻¹ for TN and 0.011 mg l⁻¹ for TP, reflecting background concentrations for minimally impacted watersheds. Median stream concentrations of TN in agricultural areas are about eleven times higher than in undeveloped areas; and are about five times higher in developed areas than in undeveloped areas. Median stream concentrations of TP in developed areas have about eight times higher concentrations than undeveloped areas; and are about four times higher in agricultural areas than in undeveloped areas. Concentrations of TN and TP increased substantially as the combined percentage of agricultural and developed land use increased. Fragmented data storage practices (e.g. incomplete metadata, ambiguous site names, and missing coordinates) and inconsistencies in monitoring protocols (e.g., differences in constituents measured, parameter names, and measurement methods) made leveraging the secondary use of multiple sources of data challenging. Nonetheless, our integrated dataset is robust, represents the best data available, and provides a new window into the nutrient status of Pennsylvania’s surface waters. The long-term median nutrient concentrations reveal the magnitude of variability in TN and TP concentrations across the state’s diverse environmental settings of land use, physiography, and geology. This information is useful for interpreting additional monitoring data, informing evaluation of water quality conditions, and guiding watershed management.

地表水的营养污染是一个普遍的问题，需要对水质状况进行区域评估。在这项研究中，我们量化了宾夕法尼亚州河流和河流中总氮（TN）和总磷（TP）的长期中值养分浓度，并探讨了河流养分浓度与其流域土地利用之间的关系。我们的分析基于来自多个机构的监测数据的综合，其中包括2000–2019年间观察到的营养物浓度记录。在全州范围内，在主要不发达地区（例如，森林，灌木和草原）观察到的溪流养分浓度的中位数浓度值，TN值分别为0.42 mg l ^-1和0.011 mg l ^-1TP，反映了受影响最小的流域的背景浓度。农业区域中总氮的中位浓度比不发达地区高约十一倍；并且在发达地区比未发达地区高出五倍。在发达地区，TP的中位浓度比未发达地区高约八倍；农业地区的土地价格是未开发地区的四倍。TN和TP的浓度随着农业和发达土地使用的总百分比的增加而大大增加。零散的数据存储做法（例如，元数据不完整，站点名称不明确以及坐标丢失）和监控协议中的不一致（例如，所测量的成分差异，参数名称，和测量方法）使得利用多种数据源的二次使用具有挑战性。尽管如此，我们的综合数据集功能强大，代表了可用的最佳数据，并为了解宾夕法尼亚州地表水的营养状况提供了新的窗口。长期中值营养物浓度揭示了该州土地利用，地貌学和地质学不同环境设置中TN和TP浓度的变化幅度。此信息对于解释其他监视数据，通知水质状况评估以及指导流域管理非常有用。长期中值营养物浓度揭示了该州土地利用，地貌学和地质学不同环境设置中TN和TP浓度的变化幅度。此信息对于解释其他监视数据，通知水质状况评估以及指导流域管理非常有用。长期中值营养物浓度揭示了该州土地利用，地貌学和地质学不同环境设置中TN和TP浓度的变化幅度。此信息对于解释其他监视数据，通知水质状况评估以及指导流域管理非常有用。