Effects of water conveyance embankments on riparian forest communities at the middle reaches of the Tarim River, Northwest China

Abstract

ABSTRACTEcohydrological research focuses on the relationship between changes in the hydrological conditions and the response of plant communities to those changes. To save the degraded riparian forests at the lower reaches of the Tarim River, water conveyance embankments (whose goal is to prevent water from overflowing the riverbanks) were constructed mid‐stream in order to guide the watercourse down to the river's destination. To investigate and evaluate the influence of these embankments on the Tarim River's riparian forest communities, we prepared three monitoring sections (five others were added later) that included six monitoring wells, six vegetation sample plots and six soil profiles at each section. From 2001 to 2007, data on groundwater depth, vegetation coverage, species diversity, total dissolved solids and concentrations of ions were collected and analysed. The results indicate that groundwater depths gradually increased, total dissolved solids and major ions in groundwater sharply increased and vegetation coverage and species diversity declined. Moreover, at the start of our investigation, the hydrological connection extended more than 1000 m from the embankments; by 2007, however, the region beyond 800 m had become a water and salinity discharging area. On the basis of these findings, the removal of the embankments should be urgently considered to protect the riparian forest ecosystems. Copyright © 2013 John Wiley & Sons, Ltd.