Title of article :
Complex hydrological controls on wet dune slacks:
The importance of local variability
Author/Authors :
M.L.M Jones، نويسنده , , ?، نويسنده , , B. Reynolds a، نويسنده , , S. Hughes & S.A. Brittain، نويسنده , ,
D.A. Norris a، نويسنده , , P.M. Rhind b، نويسنده , , R.E. Jones، نويسنده ,
Issue Information :
هفته نامه با شماره پیاپی سال 2006
Abstract :
Dune slacks are a species-rich habitat controlled largely by water chemistry and fluctuations in groundwater. Changes in water
chemistry and water table level were analysed in 8 piezometers and 15 ephemeral surface water locations at a large UK dune
system over a 12-month period. Total nitrogen concentrations in groundwater varied from 0.27–8.21 mg N L−1, where dissolved
organic nitrogen was dominant at the low nitrogen locations and nitrate was dominant at the high nitrogen locations. Principal
components analysis of the water chemistry suggests at least four chemically distinct groundwater signatures. Water levels showed
strong temporal heterogeneity. Comparisons of water levels with antecedent rainfall identified a component of year-round
groundwater feed and differing seasonal responses overlain by a complex series of lags. In summer, there were lags of four, six and
seven months with an additional rapid peaky response to daily rainfall with a one-day lag. In winter, water levels were strongly
influenced by exogenous groundwater supply, but again exhibited multiple lags. This study shows that local variations in water
chemistry and in hydrological regime can be more complicated than previously thought, with clear implications for optimum
management of these high priority habitats for conservation
Keywords :
Hydrochemistry , Sand dunes , nitrate , groundwater , water table
Journal title :
Science of the Total Environment
Journal title :
Science of the Total Environment