122
G. R. POTTS AND Q. P. VICKERMAN
was evident, with the downland sites possessing the highest diversity
and the spring barley the lowest (Fig. 6 ) .
Winter barley
ob
ib
:
o : 04b; o
A0
I
I ' 500 I I ' I '
I C
Number of individuals (loq.scaie)
FIG. 5. Species frequency abundance curves for adult Coleoptera at four sites
ranging from downland to spring barley, baaed on pitfall traps in 1969.
B. F A U N A L D I V E R S I T Y A N D U N D E R S O W I N G
Grassland may be established by the undersowing of cereal crops
with grass or grass-legume mixtures. The fauna of undersown cereal
crops is probably more varied than that of ordinary cereal crops.
The effect of uridersowing was measured by investigating the fauna
emerging in the spring from the fields which had either been undersown
the previous year or had been cultivated after harvest.
Two adjacent fields, separated only by a wire fence, were sampled
each year, one field being undersown in each case. Two rows of emergence
traps (as in Southwood, 1966, Fig. 70a, p. 242) were placed in each
field. In the two years 1970 and 1971 a total area of 11.2 m2
was covered by the total of 40 traps. Details of the sites are given on
page 123.
The arthropods from samples (5) and (7) and from (6) and (8) were
combined, and the species abundance curves are given in Fig. 6.
The results showed that 38% more arthropod taxa emerged from
undersown fields than from cultivated fields. The diversity of the
fauna emerging from undersown pastures (a = 11) was also greater
G. R. POTTS AND Q. P. VICKERMAN
was evident, with the downland sites possessing the highest diversity
and the spring barley the lowest (Fig. 6 ) .
Winter barley
ob
ib
:
o : 04b; o
A0
I
I ' 500 I I ' I '
I C
Number of individuals (loq.scaie)
FIG. 5. Species frequency abundance curves for adult Coleoptera at four sites
ranging from downland to spring barley, baaed on pitfall traps in 1969.
B. F A U N A L D I V E R S I T Y A N D U N D E R S O W I N G
Grassland may be established by the undersowing of cereal crops
with grass or grass-legume mixtures. The fauna of undersown cereal
crops is probably more varied than that of ordinary cereal crops.
The effect of uridersowing was measured by investigating the fauna
emerging in the spring from the fields which had either been undersown
the previous year or had been cultivated after harvest.
Two adjacent fields, separated only by a wire fence, were sampled
each year, one field being undersown in each case. Two rows of emergence
traps (as in Southwood, 1966, Fig. 70a, p. 242) were placed in each
field. In the two years 1970 and 1971 a total area of 11.2 m2
was covered by the total of 40 traps. Details of the sites are given on
page 123.
The arthropods from samples (5) and (7) and from (6) and (8) were
combined, and the species abundance curves are given in Fig. 6.
The results showed that 38% more arthropod taxa emerged from
undersown fields than from cultivated fields. The diversity of the
fauna emerging from undersown pastures (a = 11) was also greater