High resolution nitrogen runoff chemical data from alternate furrow flood irrigated cotton field

This collection contains nitrogen runoff data for an alternate furrow flood irrigation system. Data contains concentration and flow values, disaggregated by furrow type for irrigations 1, 2 and 4 of a single season. Chemical data includes pH, electrical conductivity (EC) and water temperature measured in situ, and nitrate—N (NO3—N), ammonium—N (NH4—N), urea—N and total dissolved N (TDN) measured from collected samples. Chemical sampling occurred at 30 minute intervals within irrigations. Flow data was measured at 30 second intervals. Data was performed at the Australian Cotton Research Institute (ACRI), Narrabri Australia.\nLineage: The field site at the Australian Cotton Research Institute (ACRI) had furrows ~130 m long at 1 m spacing, approximately 20 cm high. Soil was high shrink-swell, haplic, self-mulching medium Grey Vertosol. Data was collected approximately 5 m from end of furrow, with special care taken to avoid tail drain back-up contamination. Supply water measurements were taken from the head ditch immediately prior to syphon supplying given furrow.\nChemical data includes pH, electrical conductivity (EC) and water temperature measured in situ using a TPS Aqua-CP/A multi-probe, and nitrate—N (NO3—N), ammonium—N (NH4—N), urea—N and total dissolved N (TDN) measured from collected samples using an Alpkem Segmented Flow Analyser, Alpkem Corporation, Perstorp Analytical Co., Wilsonville, OR 97070 USA. \nFlow data from individual furrows were collected using portable long-throated Replogle-Bos-Clemmens (RBC) flumes, installed prior to each irrigation event. VanEssen Baro Diver pressure sensors were used to measure water height in the flumes, from which flow was calculated.

本数据集收录交替沟灌系统的氮素径流数据。数据包含浓度与流量两类指标，按单季第1、2、4次灌溉的沟垄类型进行细分。化学指标数据涵盖原位测定的pH值、电导率（electrical conductivity，EC）及水温，以及通过采集水样测得的硝酸盐态氮（NO3—N，nitrate—N）、铵态氮（NH4—N，ammonium—N）、尿素态氮（urea—N）与总溶解氮（total dissolved N，TDN）。化学采样在每次灌溉期间以30分钟为间隔开展，流量数据则以30秒为间隔采集。所有数据采集工作均于澳大利亚纳拉布里的澳大利亚棉花研究所（Australian Cotton Research Institute，ACRI）完成。
数据集溯源：该试验场地位于澳大利亚棉花研究所（ACRI），沟垄长约130米，间距1米，垄高约20厘米；土壤属于高胀缩性、强腐殖化自覆型中度灰色变性土（Grey Vertosol）。采样点设置在距沟垄末端约5米处，全程采取专项防护措施以避免尾渠回水污染；供水水质测量在向指定沟垄输水的虹吸管之前的进水渠中即刻完成。
本次化学指标的测定中，pH值、电导率（EC）及水温采用TPS Aqua-CP/A多参数水质分析仪原位测定；硝酸盐态氮、铵态氮、尿素态氮及总溶解氮则通过采集的水样，使用美国俄勒冈州威尔逊维尔市97070区域珀斯托普分析公司阿尔克姆分部的阿尔克姆分段流动分析仪完成检测。
各沟垄的流量数据通过便携式长喉道Replogle-Bos-Clemmens（RBC）水槽采集，该水槽在每次灌溉前完成安装；采用VanEssen Baro Diver压力传感器测量水槽内水位高度，进而计算得到流量值。