Time series of water parameters, nutrient, and gas samples in the Coffs Creek estuary, March 2018

Measurements of water parameters of temperature, dissolved oxygen, and salinity as well as nutrient samples of dissolved organic carbon, filtered and unfiltered nitrogen, and nitrous oxide were collected through time series apparatus, hourly and 3 hourly, over 185 hours and exclusively at one site in the lower estuary (Site 1). A calibrated Hydrolab MS5 sonde measured and logged water temperature (±0.02°C), DO (±0.2 mg/L), and salinity (±0.02) at 30 m intervals and a depth logger (CTD diver) measured water depth in 15-minute intervals. Nutrient samples (including duplicates), filtered and unfiltered, were collected with a sample-rinsed 60 mL polyethylene syringe. Samples for dissolved organic carbon (DOC) analysis were filtered using pre-combusted 0.7 µm GF/F filters (Whatman), into 40 mL borosilicate vials (USP Type I). Samples for nitrogen were immediately filtered using Satourious ™ 0.45μm cellulose acetate syringe filters into 10 mL polyethylene sample tubes. All samples were kept in a cold icebox, away from light, for less than 5 hours and then frozen until laboratory analysis. Nutrient analysis of DOC was performed with the 40 mL borosilicate vials (USP Type I) first treated with 30 µL of H3PO4 before analysis using an Aurora 1030W TOC Analyser (Thermo Fisher Scientific, ConFLo IV). Nutrient analysis of ammonium (NH4+), NOx (nitrate plus nitrite), and total dissolved nitrogen (TDN) was performed on the 10 mL polyethylene sample tubes colourimetrically using a Lachat Flow Injection Analyser. Total dissolved nitrogen and dissolved inorganic nitrogen were calculated from the nitrogen samples. N2O samples were collected from a time series gas equilibration device via a one-way valve into 150 mL syringes then transferred from the syringes into a Supelco company 1 L gasbag. A total of 800 mL of gas was taken per sample. The gasbags were analysed for N2O using cavity ringdown spectroscopy on a calibrated Picarro G2308.

本数据集通过时序监测设备，在河口下游单一站点（站点1）开展总计185小时的每小时及每3小时采样，采集了水温、溶解氧（dissolved oxygen, DO）、盐度等水体参数，以及溶解有机碳（dissolved organic carbon, DOC）、过滤与未过滤态氮、一氧化二氮（nitrous oxide, N2O）等营养盐样品。经校准的Hydrolab MS5水质探头（Hydrolab MS5 sonde）以30米水深为间隔，测量并记录水温（精度±0.02°C）、溶解氧（精度±0.2 mg/L）与盐度（精度±0.02）；同时采用CTD型水深记录仪（CTD diver）以15分钟间隔测量水深。使用经样品润洗的60 mL聚乙烯注射器采集营养盐样品（含平行样），涵盖过滤与未过滤态样品。用于溶解有机碳分析的样品，经预灼烧的0.7 µm GF/F滤膜（Whatman品牌）过滤后，收集至40 mL硼硅酸盐样品瓶（USP I型）中。氮分析样品则即刻使用赛多利斯（Sartorius™）0.45μm醋酸纤维素针式滤器过滤至10 mL聚乙烯样品管内。所有样品均置于避光冷藏箱中保存不超过5小时，随后冷冻保存直至实验室分析。
溶解有机碳的分析采用经30 μL磷酸预处理后的上述40 mL硼硅酸盐样品瓶（USP I型）样品，使用Aurora 1030W总有机碳分析仪（赛默飞世尔科技，搭配ConFLo IV接口）完成检测。针对铵态氮（NH4+）、NOx（硝酸盐与亚硝酸盐总和）及总溶解态氮（TDN）的营养盐分析，采用比色法通过Lachat流动注射分析仪对10 mL聚乙烯样品管内的样品进行检测。总溶解态氮与溶解态无机氮可由前述氮样品计算得到。
一氧化二氮样品通过时序气体平衡装置经单向阀采集至150 mL注射器中，随后转移至Supelco公司的1 L气体采样袋内，每份样品采集气体总量为800 mL。使用经校准的Picarro G2308腔衰荡光谱仪对气体采样袋中的一氧化二氮进行检测。