Download (1906Kb)

Soil coqaction does not appear to be a mjor proLlem in graeed
hill and upland areas bec~use of low at mldng rates, infrequent
use of agricu1tur:~l vehicles, recovery of conpacted so51 under the
influence of the frequent mhter frosts and, in the aase of animals,
by the swamping of trampling effects by the beneficial effects of dung
and urine depositf on.
Soil disturbance occurs on much-used tracks, particularly on soils
rich in clay, organic mtter and moisture, on steep slopes where
animls -bend to slip a d slide and for cattie rather than for the
lighterst spping sheep. Any disturbed soil is suscefli ble to erosion
aa can be seen on hill paths in wet weather, Hollows cPeaked on
hill-aaes by sheep action are focal points for sheet ereaim.
However, the extent to which the varying rates of erosion in the
Lake Rstrict in the past and present can be attrihted to the
effect' of aiimls is unclear,
TraqLin~ and defoliation by grazing may result lt ditmge to, and hence
in redwed produot ion by, plants,
Ao plants differ in their sensi.blvi*
to cLam?,ke and t o changed sail conditions resulting from trampling,
grczing animals can elloourage changes in the vegetation composition vrhich
my lead ultimately to soil changes associated with changes in the type
and anount of ~ 1~n-k ramins redcbing the auil surface.
On hill-land ungrazed by domest icuked atlimals , plant materia.1 eva&uaf ly
dies and f oms prt of the, surfwe mat of plant remiins.
The type of
decomposition which this mt undergoes under the influence of the high
rainfp-U and lon temperatures of upland areas, encoureges high acidity
and 20wnutrrient availzbility in the upper soil,
Gracing charnels
an increased proportion of the herbage through the animal and so reduoea
the supply to the'mt.
The effeots of a reduced mt and of deposited
dung and urino change the chemical characttfistics of the upper soil,
increasing nutrient availability and turmover.
Thi a, together with
select iva f eedjllg by animls~ particularly by sheep, encourages changes
in the vegetation,