Application of Composite Water Quality Identification Index on the water quality evaluation in spatial and temporal variations: a case study in Honghu Lake, China

Abstract

Composite Water Quality Identification Index (CWQII) and multivariate statistical techniques were used to investigate the temporal and spatial variations of water quality in Honghu Lake. The aims are to explore the characteristics of water quality trends in annual, monthly, and site spatial distribution and to identify the main pollution factors The monthly change rules of water quality were influenced by a superposition of natural processes and human activities. In samples numbered 1-9 from upstream to downstream, the maximum values of CWQII often occurred in sample site 9 while the minimum ones often occurred in sample site 2, indicating that the water quality near the upstream tributary was the poorest and that in the core zone was the best. Incoming water from the trunk canal of the Sihu area upstream was the largest pollution source. The sensitive pollution nutrients were mainly caused by the total nitrogen, followed by the total phosphorus.

Occurrence and ecological hazard assessment of selected antibiotics in the surface waters in and around Lake Honghu, China

“…This area experiences a subtropical humid monsoon climate, with an annual mean precipitation and air temperature of 1000-1300 mm and 15.9-16.6°C, respectively. The rainy season usually occurs during April-October, which accounts for about 77% of the total annual precipitation (Ban et al, 2014).…”

Spatio-Temporal Patterns and Source Identification of Water Pollution in Lake Taihu (China)

“…For instance, cluster analysis (CA), discriminant analysis (DA) and principal component analysis (PCA) have been widely used to assess spatial or temporal variations of groundwater and surface water quality [12][13][14][15][16]. However, reciprocal validation between any two multivariate analyses is still required to validate the results obtained by each approach [7].…”

Quantitative Impacts of Climate Change and Human Activities on Water-Surface Area Variations from the 1990s to 2013 in Honghu Lake, China

“…Honghu Lake is also the largest natural wetland on the Jianghan plain, which is surrounded by the mainstream of the Yangtze River and the Dongjing River, a tributary of the Hanjiang River. Due to the increasing human activities, the lake and wetland suffer a series of eco-environmental problems in recent years, such as water-surface shrinking, wetland deterioration and water quality deteriorated [11,15]. In order to prevent this degeneration, with the support of the State Forestry Administration (SFA), China, World Wide Fund for Nature (WWF) and local government and sectors, the Honghu Lake wetland protection and restoration demonstration project has been implemented since 2004.…”

“…The extreme climate events (i.e., flood and drought) are so frequent in the mid-lower reaches of the Yangtze River that the water-surface area of Honghu Lake can change greatly on both short and long time scales due to precipitation and temperature anomalies. Especially since the 1950s, Honghu Lake has been separated from the Yangtze River by several sluice gates, and hardly been modulated by upstream of Yangtze River [11]. From this point, Honghu Lake area has decreased dramatically, which is mainly caused by excessive human activities mainly including reclamation and aquaculture [12].…”