Stream chemistry for watershed 263 (urban) sites - Spreadsheet format BES ID 580-

In the Baltimore urban long-term ecological research (LTER) project, (Baltimore Ecosystem Study, BES) we use the watershed approach to evaluate integrated ecosystem function. The LTER research is centered on the Gwynns Falls watershed, a 17,150 ha catchment that traverses a gradient from the urban core of Baltimore, through older urban residential (1900 - 1950) and suburban (1950- 1980) zones, rapidly suburbanizing areas and a rural/suburban fringe. Our long-term sampling network includes four longitudinal sampling sites along the Gwynns Falls as well as several small (40 - 100 ha) watersheds located within or near to the Gwynns Falls. The longitudinal sites provide data on water and nutrient fluxes in the different land use zones of the watershed (rural/suburban, rapidly suburbanizing, old suburban, urban core) and the small watersheds provide more focused data on specific land use areas (forest, agriculture, rural/suburban, urban). Each of the gaging sites is continuously monitored for discharge and is sampled weekly for chemistry. Additional chemical sampling is carried out in a supplemental set of sites to provide a greater range of land use. Weekly analyses includes nitrate, phosphate, total nitrogen, total phosphorus, chloride and sulfate, total suspended solids, turbidity, fecal coliforms, temperature, dissolved oxygen and pH. Cations, dissolved organic carbon and nitrogen and metals are measured on selected samples. This dataset is for Watershed 263, a 364 ha urban storm drain watershed (or sewershed), with 30,000 residents with mixed industrial, institutional, and residential land uses. In March 2004, we established long-term monitoring sites in two sub-watersheds within W283. Both are approximately 17 ha, with 20% impervious surface and 4% vegetation cover. Samples (weekly grab and flow-weighted composite) are taken in a stormwater drainage pipe.巴尔的摩城市长期生态研究（Long-Term Ecological Research, LTER）项目（又称巴尔的摩生态研究计划，Baltimore Ecosystem Study, BES）采用流域研究方法评估综合生态系统功能。本长期生态研究以格温斯福尔斯流域为核心，该流域面积达17150公顷，横跨从巴尔的摩城市核心区、经1900-1950年建成的老旧城市居住区与1950-1980年建成的郊区地带、快速郊区化区域，直至乡村/郊区边缘带的完整土地利用梯度。本项目的长期采样网络包含沿格温斯福尔斯河布设的4个纵向采样点位，以及格温斯福尔斯流域内或邻近的数个小型（40-100公顷）子流域。纵向采样点位可获取流域不同土地利用分区（乡村/郊区、快速郊区化区域、老旧郊区、城市核心区）的水体与养分通量数据，而小型子流域则能针对特定土地利用类型（森林、农业用地、乡村/郊区、城市区域）提供更聚焦的监测数据。每个水文监测点位均持续监测径流量，并每周开展水体化学采样。此外还在补充点位组开展额外化学采样，以覆盖更广泛的土地利用类型。每周监测指标包括硝酸盐、磷酸盐、总氮、总磷、氯化物、硫酸盐、总悬浮颗粒物、浊度、粪大肠菌群、水温、溶解氧与pH值。阳离子、溶解性有机碳、溶解性有机氮及金属元素仅在部分选定的采样样本中测定。 本数据集对应263号流域，该流域面积364公顷，为城市雨水管流域（或称污水汇水区，sewershed），居住人口30000人，土地利用类型涵盖工业、公共设施与住宅混合用途。2004年3月，我们在W283的两个子流域内设立长期监测点位。这两个子流域面积均约为17公顷，不透水地表占比20%，植被覆盖率4%。采样方式包括每周采集瞬时水样与流量加权混合水样，采样点位设于雨水排水管内。