two ryegrass treatments (Table 3). There was also a trend for bacterial
feeders (P ¼ 0.074) to be found in greater numbers in the
ryegrass treatments; although omnivores and predator abundance
was similar across treatments. There were seasonal differences in
both fungal and herbivorous nematode functional groups, with
both having greater numbers in the spring compared to the autumn
(P ¼ 0.031 Fungal; P ¼ 0.008 Herbivores), although there were no
forage season interaction effects.
3.3. Microarthropod populations
An average of 35,000 (±3200) microarthropods per m2 were
extracted across all treatments and both sampling periods; nearly
60% were mites and 35% Collembola, whilst the other 5% were
classified as “other” invertebrates. The abundance of both the
Collembola and the mite orders did not differ among forage
treatments (Table 4). There were differences however, between the
two sampling periods, with greater abundance of both Collembola
(P ¼ 0.041) and mites (P ¼ 0.051) in the spring sampling compared
to the autumn. Two collembolan superfamilies did show significant
differences between treatments (Poduromorpha and Symphypleona);
whilst two did not (Entomobryomorpha and Neelipleona
(Table 5a)). The detritivorous Poduromorpha had greater abundances
in the alternative forages; whilst the herbivorous Symphypleona
had larger abundances in the ryegrass 200 N (Table 5a). The
three main mite lineages did not differ in abundance across treatments
(Table 5b) however there was a trend towards greater
numbers of the predatory Mesostigmata in red clover (P ¼ 0.061),
and a greater abundance of Prostigmata in the ryegrass low N
(P ¼ 0.076). Both the Mesostigmata (P ¼ 0.027) and the Prostigmata
(P ¼ 0.015) differed across sampling period (Table 5b), with Mes