Abstract

Info

Title:: Spatial Variability Characteristics of Eh and pH in West Dongting Lake Wetland and Analysis of Their Impact Factors

Author(s):: ZHOU Nian-qing; LI Zhang-ping; LI Dan; LIU Xiao-qun; 1. School of Civil Engineering, Tongji University, Shanghai 200092, China；2. Dongting Lake Water Resource Administration Bureau of Hunan Province, Changsha 410007, Hunan, China

Keywords:: wetland; Eh; pH; spatial variability; impact factor; variable coefficient; Dongting Lake

Abstract:: The spatial distribution characteristics of Eh and pH are the basis of studying contaminant existing form, migration and transformation mechanism in wetland. 12 drilling holes of the two monitoring sections are deployed in the estuary wetlands of Li River and Yuan River of the West Dongting Lake, Hunan Province, and the depths of holes are 8.0-14.0 m. Distribution pattern and spatial variability of Eh and pH were studied by the site and laboratory tests in the wetland hyporheic zones, and the impact factors were discussed. The results show that the Eh values are -57.8-238 mV with the average of 124.67 mV, and the pH values are 5.1-9.1 with the average of 7.4; the hyporheic zone of West Dongting Lake wetland is weak alkaline and reduction environment; the variable coefficients of Eh and pH are 49.60% and 11.66% respectively, and belong to medium intensity variation; the complex profile distribution characteristics of Eh and pH are layer distribution with patches; soil type, underground water level, moisture and temperature have important influences on Eh; pH is mainly affected by soil type and underground water level, whereas temperature and moisture are not significant.