Macro‐invertebrate associations in sewage filter‐beds and their relationship to operational practice

Abstract

Summary 0[ The macro!invertebrate faunas of 56 _lter!beds in 37 sewage works throughout Great Britain were surveyed in relation to the physico!chemical characteristics of the bed environment[ Faunal samples were collected from the surface medium and from the bed e/uent[ Fifty!nine of the beds were sampled twice "autumn and spring#^the others were sampled in the spring only[ 1[ Eighty!seven species were found\ of which 28 occurred in the surface samples[ Of these latter species\ 13 "nine oligochaetes\ eight insects\ four copepods and three mites# were particularly successful\ being widespread and often abundant[ The worm Lumbricillus rivalis\ the moth~y Psychoda alternata and the mite Histiostoma feron! iarum were almost ubiquitous[ 2[ The _lter!bed fauna was essentially hygropetric and microbivorous[ All but one "the predatory mite Platyseius italicus# of the 13 particularly successful species grazed the bio_lm[ 3[ The successful species characteristically had prolonged or frequent periods of reproduction[ Therefore\ they could respond rapidly to changes in the bed environ! ment and they were able to persist despite continuous wash!out from the bed[ 4[ DECORANA ordination indicated that abiotic variables likely to a}ect faunal com! position were principally] the organic loading the bed received\ the amount of bio_lm present\ air temperature\ the size of the bed medium\ and bed age[ All except air temperature are under operational control\ so there is potential for the faunal com! munity structure to be modi_ed\ if required\ by manipulation of the bed environment[ 5[ Classi_cation by TWINSPAN identi_ed the moth~y Psychoda albipennis and the copepod Bryocamptus pygmaeus as indicators of beds that received a low organic loading\ whereas abundant Psychoda alternata "×0999 larvae litre −0 medium# indi! cated more heavily loaded beds[ 6[ The results of the present study emphasize the prime importance of the physico! chemical environment in shaping faunal community structure in sewage _lter!beds[ 7[ The study illustrates how knowledge of the faunal community of sewage _lter!beds and its relationship to the bed environment and to bed performance can potentially aid the management of such beds to improve puri_cation e.ciency or reduce~y nuisance[ Key!words] multivariate analysis\ sewage _lter!bed fauna\ species associations[ Journal of Applied Ecology "0887# 24\ 619Ð636

Habitat Selection and Winter Food Resources of the Water PipitAnthus spinolettain South-Western Poland

“…Their occurrence in warm wastewater is widespread in sewage treatment plants and sedimentation basins (e.g. Learner 2000), with the elevated water temperature allowing all year round development of invertebrates (Learner & Chawner 1998). Eristalis larvae abound in waters highly contaminated with sewage, occurring also in vast numbers in heaps of manure.…”

Can freshwater mites act as forensic tools?

“…They are non-swimming, and usually occupy the surface film rather than deeply submerged substrates. Learner and Chawner (1998) observed high densities of[100 individuals/l of Platyseius in sewage beds in the United Kingdom. Semi-aquatic Mesostigmata are predators of nematodes and small arthropods, and could potentially be attracted to saprophagous invertebrates that themselves are feeding on corpse tissues near the water's surface.…”

Population dynamics of free-swimming Annelida in four Dutch wastewater treatment plants in relation to process characteristics

“…Maximum worm densities found by other researchers in different wastewater treatment systems were variable. In large-scale plants the maximum densities varied from 0.3 Naidinae/ml (Learner & Chawner, 1998) and 30 Aeolosomatidae/ ml (Poole & Fry, 1980) to 160 N. elinguis/ml (Ratsak, 1994). In contrast, the maximum densities in lab-scale systems were much higher.…”

“…Learner (1979) mentioned the presence of several Naidinae (Aulophorus furcatus, Chaetogaster diaphanus, C. langi, Nais barbata, N. elinguis, N. variabilis, Pristina aequiseta, P. foreli, and P. idrensis) in sewage filterbeds throughout Britain. Learner & Chawner (1998) described a study in which the macro-invertebrate fauna of 67 biofilters in 48 WWTPs in Britain was sampled once or twice in the 1960s and related to the physico-chemical characteristics (such as F/M: Food to Microorganism ratio, temperature, geographic location, and pH) of the biofilter environment. Nais spp.…”