Qingdao University, 308 Ningxia Road, Qingdao, Shandong, 266071, China.
Qingdao University of Technology, 11 Fushun Road, Qingdao, Shandong, 266033, China.
Environ Sci Pollut Res Int. 2020 Oct;27(28):34586-34595. doi: 10.1007/s11356-018-4038-z. Epub 2019 Jan 12.
Nowadays, urban rivers play an important role in city development and make great contributions to urban ecology. Most urban rivers are the drinking water sources and water quality is extremely critical. The current assessment method in national standard of China has multiple limitations; therefore, this paper introduces an advanced assessment, that is, Canadian Water Quality Index (CWQI). This method can help to provide comprehensive and objective water quality assessment for the urban rivers. Moreover, CWQI can prevent waste of the water resource, since current assessment is pessimistic and tent to underestimate water samples to a lower grade. Linyi development area is selected as study region and CWQI method is applied to assess two major urban rivers within the area. The water monitoring data from 2014 to 2017 is acquired in 24 parameters. Since the CWQI calculation is still based on traditional water quality measurement in parameters, there will be a huge cost when increasing research scale and accuracy. In this paper, remote sensing technique is employed to develop models of CWQI scores from satellite data. By utilizing 23 selected monitoring instances and matching satellite data, linear regression analysis shows that red band data has highest correlation with CWQI in both two urban rivers in the study region. In addition, two testing datasets with five instances for each river are used to validate the RS-based CWQI models and the results show that testing datasets can be fitted well. With the models, CWQI distribution diagrams are generated and assist both spatial and temporal analysis. Experimental results show that the proposed approach can indicate actual water quality pattern which is validated by field visit. The proposed approach in this paper has satisfying effectiveness and robustness.
如今，城市河流在城市发展中扮演着重要的角色，对城市生态做出了巨大贡献。大多数城市河流是饮用水源，水质极其关键。中国国家标准中的现行评估方法存在多种局限性；因此，本文引入了一种先进的评估方法，即加拿大水质指数（CWQI）。这种方法可以帮助对城市河流进行全面客观的水质评估。此外，CWQI 可以防止水资源的浪费，因为当前的评估方法过于悲观，倾向于将水样低估一个等级。选择临沂市开发区作为研究区域，并应用 CWQI 方法评估该区域内的两条主要城市河流。获取了 2014 年至 2017 年的 24 项参数的水质监测数据。由于 CWQI 的计算仍然基于传统的水质测量参数，因此在增加研究规模和提高准确性时，将会产生巨大的成本。本文利用遥感技术，从卫星数据中开发 CWQI 评分模型。通过利用 23 个选定的监测实例和匹配的卫星数据，线性回归分析表明，在研究区域内的两条城市河流中，红波段数据与 CWQI 相关性最高。此外，还使用了两条河流各五个实例的两个测试数据集来验证基于 RS 的 CWQI 模型，结果表明测试数据集可以很好地拟合。利用这些模型，生成了 CWQI 分布图表，并辅助进行空间和时间分析。实验结果表明，所提出的方法可以通过实地考察验证实际水质模式，具有令人满意的有效性和稳健性。
