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200000 kg 1 M) ha-'. Grant (pars. o ma. ) otllculitcd that
1.6-72.0 kg potassium (K), 9-72 kg Ca, 5-40 kg P and 3 - 240
kg N 100 ha-'
was removed fro^ the Scat tish hill ooosyatcm by
a a le of lads and cast ewes rvith recpectivcly 0,5-0.66 waea
ha-'
and 7% lambing success and 1-2 owes hh' and 100$6 lilmbing,
King & fiichols on (j 964.) e st j-mated that nutrierit removal in
sheap prducts in Scotland amounted to 22 kg Ca and 11 kg P
103 he-' with 0.625 sheep ha-' ,
Althorn the above calmlatiuns vary in c*~?-lyticyl d-:kc umd
and in the rhtio of weights of. -sheep cczrcase .to wool, sheep
consistently appear to remove small anounta of nutfie~zts :but
+,his stcltecont I'L quirb s thm~
qu~llif'icakions.
1 ) As mny authors hzvo shcim, sheep are highly selecti vo grazers,
so fiutrient rcmovnl is conccntr;:ted on the most palatable
parks of the sward particuhrly A ~ r o s t i * w grasslad.
The latter my comprise less than 2%
of e mixed moor
in the Pennin~s (hies & Welch, 1 969) with 2.2 sheep hav'
but my support an averege of up to ~bmt 9 sheep ha-'.
This is in the range of 5.6-18.2 ewe units ha-' found for
similar grassland in Wales (Hughes et a1 '1964). Assuning
9 sheep ha-', then the loss of P in sheep at Moor House is
about 29 kg 100 hn',
c* 5% of the input in the rain,
vhcreas for the Lake District the P loss would be abaut
30 kg 103 hdl, sirr&lar to that in precipitation. Fiannop
(I 965) exprcsaed some doubts about the ~ bility of Scuttish
hill soils to replenish the P rensoved h sheep.
Smila~
aoubts my also apply for P and other nutrients in the Lake
District for the areas of more palatable herbage,