There is a growing need to reclaim wastewater for agricultural use due to freshwater limitation. Integrating macrophytes in vermifiltration improves the treatment efficiency. However, the effect of treated wastewater on seed germination and seedling development is not widely investigated. The study investigated the use of Pistia stratiotes in a macrophyte-assisted vermifiltration of domestic wastewater and assessed the effect on seed and seedling development of Zea mays, Triticum aestivum and Sorghum bicolor. Three irrigation treatment water wee applied; macrophyte-assisted vermifiltration (VP), no macrophyte vermifiltration (VM) and potable water (PW), as the control. Results showed that VP had a removal of 41–44% EC, 65–67% turbidity, 52–65% TDS, 67–70% TSS, 29–34% COD, 42–46% BOD, 67–70% N tot, and 74–78% P avail compared to VM. VP treatment reduced inhibition in the morphological, physiological and biochemical developments of seed and seedling growth. The use of macrophyte-vermifiltered wastewater significantly (p < 0.05) increased the percentage of germination and the radical length of all seed species increased as well. In terms of the seedling development, seedling mortalities were significantly (p < 0.05) reduced and more than 75% Chlorophyll pigments estimations (Cɑ, Cɓ, Cɑ+ɓ and Cx+c) were identified in all seedling species when macrophyte-vermifiltered wastewater was used to irrigate.

Developing countries are facing high generation of fecal sludge without adequate systems for proper treatment, leading to detrimental effects on the environment from its disposal. An emerging and innovative option in curbing this problem is the use of epigeic earthworm species to stabilize the waste into vermicompost, a value‐added resource. Substrate enrichment techniques can be applied to promote the sustainability and effectiveness of the vermicomposting process. This study was therefore carried out to determine the potential of two epigeic earthworm species (Eisenia foetida and Eudrilus eugeniae) to transform and stabilize fecal sludge into vermicompost using organic enriched substrates. Enriched substrates were prepared with 160 g of coconut coir, 120 g of fecal matter (65–70% dry matter) and 80 g of organic black soil. Three treatments of the vermibed substrates were prepared which were labelled T1, T2 and T3, with T1 containing Eisenia foetida, T2 containing Eudrilus eugeniae and T3, the control treatment, containing no earthworm. Treatments were triplicated and about 3‐week‐old 20 clitellated, E. fetida (live weight ∼255–275 mg) were introduced into the vermibeds for vermicomposting over a duration of 12 weeks. Physicochemical parameters such as pH, organic carbon (Corg), total nitrogen (Ntot), available phosphorus (Pavail), exchangeable calcium (Caexch), iron (Fe), lead (Pb), and aluminium (Al) changes in the setups at the beginning and end of the vermicomposting period were evaluated. Eisenia foetida demonstrated a higher Corg mineralization (67.59%) compared to Eudrilus eugeniae, which attained 67.22%. Eisenia foetida also showed 5% more mortality than Eudrilus eugeniae. The study revealed that the two epigeic earthworm species for the vermicomposting of fecal waste in the enriched substrates played significant role in stabilizing the waste into vermicompost that was rich in nutrients, with lower levels of metals, higher levels of microbial biomass and higher levels of enzyme concentration.

High generation of fecal sludge without proper treatment is a major sanitation problem. A key step in curbing this problem is producing value-added resources such as vermicompost from fecal sludge through substrate enrichment. Substrate enrichment is a vermicomposting technique that involves augmenting vermibed substrates with organic rich materials to provide additional nutrients, as well as underlying layers needed for microcosm development to produce desirable vermicompost. The aim of this study was to investigate effects of substrate enrichment with organic soils (black soil, red laterite soil and sandy soil) combined with coconut coir as bulking material, on the fecal sludge vermicomposting process and quality of the end-product. The purpose of the study was to promote the development of highly nutritive vermicompost from fecal sludge using substrate enrichment as a low-cost innovative vermicomposting technique. The enriched substrates were prepared with 160g of coconut coir, 120g of fecal matter (65–70% dry matter) and 80g of organic soil. The treatments were labelled T 1 , T 2 and T 3 representing systems containing black soil, red laterite soil and sandy soil respectively. The control treatment (T 4 ) contained no soil. Triplicate treatments were setup and about 20 3-week old clitellated earthworms of the species Eisenia. fetida with live weights ranging from 255 to 275mg, released into each system for vermicomposting over a period of 12 weeks. Physicochemical parameters such as pH, Organic Carbon (C org ), Total Nitrogen (N tot ), Available Phosphorus (P avail ), Exchangeable Calcium (Ca exch ), Iron (Fe), Lead (Pb) and Aluminium (Al) were determined for both the fecal sludge and the vermicompost. The vermicompost in the setup with black soil (T 1 ) showed the highest C org mineralization and N tot , P avail and Ca exch enhancement followed by T 2 , T 3 and T 4 . Treatment T 1 also resulted in the lowest concentration of Fe, Pb and Al in the vermicompost. Concentrations of these heavy metals were found to be higher in the other treatments in increasing order of T 2 , T 3 and T 4 . Less than 16% earthworm mortality was recorded in all treatments except T 4 , in which the mortality was about 38% (38.33 ± 13.74). The enriched substrates were therefore found to provide a more suitable microclimate for earthworm development and produced vermicompost with high nutrient content. However, a more comprehensive study on metal accumulation in the earthworm tissues as a potential metal contaminant is needed to est...

Development of sustainable technology to treat domestic wastewater with added advantages of cost reduction and improved handling efficiency is crucial in developing countries. This is because, domestic wastewater from households are stored in septic tanks and are poorly treated prior discharge. This study developed a macrophyte-assisted vermifiltration (MAV) system to treat domestic wastewater. The MAV system is an integrated approach of macrophytes and earthworms in a vermifiltration and complex physicochemical mechanism processes. The use of different macrophyte and earthworm species was hypothesized by the study to affect and vary the treatment performance of the developed MAV. The study therefore aimed to evaluate the treatment performance of the developed MAV when three varied macrophyte species (Eichhornia crassopes, Pistia stratiotes and Spirodela sp.) and two varied earthworm species (Eisenia fetida and Eudrilus eugeniae) were used to design the treatment system. Treated effluents were collected every 48hours within two weeks for physico-chemical, pathogen and helminth analysis. The contaminants (Ntot, NH3, NO3-N and Ptot) in the wastewater were high (>50 mgL-1, >5 mgL-1, >1 mgL-1 and >20 mgL-1 respectively). Results revealed that the developed MAV systems were effective in the removal of solids (>60%), nutrients (>60%) and pathogens (>90%). In most cases, there were no significant differences between the selected varied macrophytes and earthworms in the treatment performances. Results therefore demonstrated that the selected macrophytes combined with the earthworm species were suitable when used in the development of the MAV system. Developing the MAV with the selected varied macrophyte and earthworm species did not only contribute to the treatment of the wastewater, but also improved the vermiculture. Eudrilus eugeniae however demonstrated higher biomass gain (5–10% more) compared to Eisenia fetida.

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In many low to middle income countries like Ghana, most wastewater treatment plants operate below capacity owing to lack of maintenance and lack of proper management. This affects the stabilization efficiency of treatment plants. The Chirapatre wastewater treatment plant was established to serve as a model system for municipal wastewater treatment in the Ashanti region of Ghana, however, very little is known about its stabilization efficiency. This study evaluated the current stabilization efficiency of the Chirapatre stabilization ponds for municipal wastewater treatment, as well as the potential reuse of the stabilized effluents for wastewater-fed aquaculture. Stabilization efficiency (SE) were assessed using the physico-chemical analysis of the influent at the anaerobic stabilization pond and effluent at discharge of the 2nd maturation pond. African catfish Clarias gariepinus fingerlings of average size 40g were stocked into two maturation ponds at a density of 3 fish/m2. Fish were not fed during the study period. Sampling was done every 14 days to monitor growth, and total fish harvest was done at the end of the study (12th week). Variables monitored included: fish survival and growth performance (condition factor, weight gain, specific growth weight and yield) as well physicochemical water quality parameters. The results indicated that TSS, TDS, alkalinity, ammonia, COD, and BOD5 stabilization efficiency were 89.99%, 62.21%, 37.54%, 67.21%, 91.33% and 88.77% respectively. The plant was non-compliant in terms of morning DO and the ammonia levels in effluents which posed lethal to aquatic life in receiving waters. However, the plant satisfied the USEPA and GEPA standards for all other physicochemical parameters including the DO (evening) concentrations in effluent. Fish survival of > 65% with > 30 condition factors and fish yields of > 1500 kg/ha were recorded at the end of the study.

Wastewater-fed aquaculture (WFA) is an innovative water reuse approach of harnessing nutrients in wastewater to culture fish. Due to possible pathogen contamination of fish tissues in WFA, it is necessary to provide precautionary and post-harvest treatments such as depuration and smoking. This study evaluated the current stabilization efficiency of effluents from the Chirapatire wastewater stabilization treatment plant in Ghana and its potential reuse for fish production. The efficacies of depuration and smoking as post-harvest treatments were also investigated. Results indicated that the stabilization efficiency of the effluent in terms of TSS, TDS, ammonia, COD, and BOD5 were all above 50% except alkalinity. Fish survival of > 65% with > 0.3 condition factors and fish yields of > 1500 kg/ha were recorded at the end of the study. Higher levels of total coliform and E. coli contamination were detected in fish tissues but got reduced through depuration and smoking.