Topsoil inversion as a restoration measure in sand dunes,early results from a UK field-trial |
| |
Authors: | M Laurence M Jones Kim Norman Peter M Rhind |
| |
Institution: | (1) Centre for Ecology and Hydrology, Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW, North Wales, UK;(2) BHP Billiton, Field Study Centre, Unit 1, Station Road, Talacre, Flintshire, CH8 9RD, North Wales, UK;(3) Countryside Council for Wales, Maes-y-Ffynnon, Penrhosgarnedd, Bangor, LL57 2DW, North Wales, UK |
| |
Abstract: | Over-stabilisation and eutrophication affect many dune systems in north-west Europe. This leads to lower diversity of typical
dune species and an accumulation of soil nutrients. Existing management techniques to remove excess nutrients include mowing,
with removal of cuttings, and turf stripping. A new restoration technique called topsoil inversion or deep ploughing may also
be able to counter some of the negative effects of eutrophication. It simulates the burial of established soils with fresh
mineral sand, by inverting the soil profile. A trial was carried out on two small blocks of eutrophic dune grassland in North
Wales, UK. Nutrient-rich surface soils were buried beneath mineral sub-sand using a double-bladed plough, designed to plough
to depths of up to 100 cm. Results show that the organic soil horizons were buried to a depth of 80 cm, and covered with 40–50 cm
of mineral sand. The pH and organic matter of the surface layers became comparable to those of mobile dunes. Fifteen months
after ploughing, bare sand cover was still 70–90%, but significant sand loss through wind erosion resulted in a thinning of
the mineral sand over-burden, leaving the buried organic layer closer to the surface. Natural vegetation colonisation was
slow, with the first surviving plants observed after 8 months. The majority of species present at 15 months were present before
ploughing and had regenerated from rhizomes or root fragments. The effect of excluding disturbance caused by rabbits, people
and dogs was assessed within fenced areas. After 11 months, vegetation cover was greater in the fenced areas than in plots
exposed to disturbance, therefore disturbance replaced physical conditions as the dominant influence on plant growth and establishment.
These early results suggest the trial has been partially successful, but that topsoil inversion could be combined with other
methods such as turf stripping or by stabilisation of the ploughed surface by planting with pioneer species, depending on
the ultimate restoration goal. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|