Feeding ecology and activity patterns of African Spoonbill (Platalea alba) in and around Lake Ziway, Ethiopia

Feeding ecology, activity patterns and habitat association of the African spoonbill (Platalea alba) in Lake Ziway were studied during March-September, 2011. A total of 28 individuals of African Spoonbills were recorded in both wet and dry seasons. They spent more time for stirring and feeding than other diurnal activities. The durations spent on stirring, feeding, movement and resting were statistically significant between seasons ( =29.9, p<0.001, = 38.1, p<0.001, =11.1, p<0.001, = 57.3, p<0.001, respectively). However, the time engaged in preening, wing display and defecation did not show significant difference between seasons. Additional studies were made in four different study sites, where the species was frequently observed. The time devoted for different activity patterns in wet and dry seasons in the study sites was statistically significant ( = 639.31, P < 0.0001). The activity patterns of African Spoonbill could influence substantially by tidal stage, rise and fall of water level in foraging sites, and other related environmental factors. Keywords: African Spoonbill, activity patterns, diet

Nutritional composition of food plants of geladas (Theropithecus gelada) in Guassa Community Protected Area, Ethiopia

Understanding the nutritional needs of geladas is a key to determine the species ecology, as adequate nutrition is a prerequisite for successful reproduction. Chemical analysis method was used for the study, and major food items which were dominantly forage by geladas in both wet and dry seasons were selected for the analysis. The result showed that there is a less diversity and abundance of food items of gelada in the study area. A total of 13 food plants of eighteen identified species eaten by the geladas in both wet and dry seasons were used for chemical analysis. These food plant species include Ranunculus multifidus, Cotula cryptocephala, Haplocarpha schimperi, Alchemilla abyssinica, Agro charis melonata, Cupressus lusitanica, Eremurus robustus,  Adenostemma  caffrum, Malva  verticillata, Galium  asparinoides, Festuca  macrophyla, Sonchus  oleraceus and Rubus  apetalus. With regard to the result of nutritive value of the preferred food plants, the highest percentages of crude protein content (27.14 %), crude fiber (48.75%), fat content (4.9%), ash (23.1%), dry matter (91.06 %) and neutral detergent fiber (45.23 %) are found in Malva verticillata, Haplocarpha schimperi, Ranunculus multifidus, Cotula cryptocephala, Sonchus oleraceus and Haplocarpha schimperi, respectively. In the study area, geladas’ food appeared to have less water and high dry matter content. This showed that water scarcity is not a serious issue in the study area for geladas’. Keywords: Feeding behaviour, food items, gelada, Guassa, nutritive valu

SPECIES COMPOSITION, HABITAT ASSOCIATION AND RELATIVE ABUNDANCE OF SMALL MAMMALS IN BORENA SAYINT NATIONAL PARK, SOUTH WOLLO, ETHIOPIA

Small mammals are ecological regulators in natural habitats. During the present investigation, species composition, distribution and relative abundance of small mammals were studied in Denkoro Forest, South Wollo, and Ethiopia from 2011 to 2012. In this investigation, Capture-Mark-Recapture (CMR) method was used. Data were collected during the wet and dry seasons by using Sherman live-traps (7.6× 8.9 × 22.9 cm. size) and snap-traps, and the traps were randomly laid at different trap sites of the habitats. The area of each live-trap grid was 70 ×70 m. Each of the grids consisted of seven lines, 10 m apart, with a trap station at every 10 m. A total of 49 Sherman traps was set in each grid, for 3 consecutive days. Ten species of small mammals belonging to rodents and insectivores were recorded from the study area. Additional two rodent species (Hystrix cristata and Trachyoryctes splendens)were sighted, but not captured. The small mammals trapped were Lophuromys flavopunctatus (35.7%), Otomys typus (28.5%), Stenocephalemys griseicauda (14.6%), Arvicanthis dembeensis (9.1%), Crocidura flavescens (5.9%), Stenocephalemys albipes (1.9%), Crocidura fumosa (1.4%), Desmomys harringtoni (0.8%), Mus Mahomet (0.6%) and Dendromus lovati (0.3%). Population abundance and species composition of small mammals varied from habitat to habitat and from season to season.  Lophuromys flavopunctatus and O. typus were the most widely distributed and abundant species, whereas S. albipes, C. fumosa (in the forest), D. harringtoni, D. lovati and M. mahomet (in the farmland) were restricted species. Seasonal variation and availability of food resulted in variation in abundance and distribution of small mammals from habitat to habitat. Disturbance of small mammals by plant trampling and cutting should be stopped since small mammals are a source of diet to the endemic Ethiopia wolf and other carnivores

Kildeseparasjon og lokal behandling av avløpsvann : et kombinert behandlings- og ressursgjenvinningsanlegg for en sirkulær økonomi

The world's water specialists agree to work on increased resource recovery from wastewater and reduced emissions to the environment. Source-separated wastewater treatment systems, which provide opportunities for local recycling and utilization of resources, are appropriate alternatives to conventional treatment of mixed wastewater in centralized treatment systems. This work includes the development of technical solutions for the treatment of source-separated blackwater, as well as studies of processes related to the treatment of black and grey wastewater from student housing inhabiting 48 students at the Norwegian University of Life Sciences (NMBU), Ås, Norway. Furthermore, the possibility of local resource utilization through biogas production and in the production of microalgae biomass based on nutrients recovered from wastewater is assessed. The main objectives of this work have been to i) develop a technical solution for a combined treatment and resource recovery in a closed cycle that creates opportunities for the circular economy, and ii) assess the efficiency of the various unit processes in terms of resource recovery and residual emissions. In the first section, a compacted greywater treatment system with different posttreatment solutions was investigated (Papers I and II). Separation of blackwater alone resulted a reduction in organic matter (OM), total suspended solids (TSS), nitrogen (N) and phosphorus (P) of 64%, 75%, 85 and 88%, respectively. Treatment of the greywater by sludge separation and biological treatment in a porous medium with attached biofilm, and post-treatment by fine sand filtration (Paper I) resulted in low emission concentrations: <2 mg O2 L-1 (BOD); <2 mg TSS L-1; <0.1 mg P L-1 and <5 Escherichia coli (E.coli) 100 mL-1. In a separate experiment, the post-treatment of the biofilter effluent with biochar and fine Filtralite (Paper II) also gave very low emission concentrations. The results showed that biological treatment plant in combination with post-treatment are appropriate solutions where the emission requirements are strict, especially in areas close to drinking water sources and where treated water can be used for watering salads and general irrigation of outdoor areas without restrictions. Separation of the blackwater greatly contributes to this. The second section of this study focused on the development and evaluation of a combined treatment and resource recovery facility for source-separated blackwater. A hybrid reactor, which integrates an up-flow sludge blanket and the anaerobic baffled reactor was developed. The performance of this reactor was tested, as an integrated treatment system for source-separated blackwater. The effects of load and feed pulses on system performance were evaluated in terms of stability, effluent quality, the removal efficiency of organic and suspended particulate matter, biogas production and methane yield (Paper III). The results showed that the total COD removal efficiency stabilized above 78 % within less than 120 days. The configuration of the reactor provided sufficient sludge expansion volume, solid-liquid separation, and biogas production rate ranged from 0.52 to 1.16 L d-1 (L reactor volume)-1. At steady state, the methane concentration ranged from 67 - 82 % with an average conversion rate of 0.69±0.2 and 0.73±0.2 g CH4-COD g-1CODin for reactor I and reactor II, respectively. Paper IV demonstrates a combined blackwater treatment and nutrient-recovery strategy for the recovery of a more dependable source of plant nutrients. The anaerobically treated blackwater effluent, rich in NH4-N and PO4-P, was treated in a sequence of upflow and downflow filtration columns using granular activated carbon, Cocos char and Polonite. The flow rate was set at 600 L m-2 day- 1. Filtration of the anaerobically treated effluent through activated carbon removed over 80% of the residual organic matter, more than 90% of suspended solids and turbidity while releasing more than 76% NH4–N and 85% of PO4–P in the liquid phase. The treatment train also removed total coliform bacteria (TCB) and E. coli, achieving concentrations below the detection limit after the integration of 11 W ultraviolet (UV) light. This integrated technological approach ensured simultaneous nutrient recovery as a nutrient solution, inactivation of indicator organisms, and reduction of organics. The treated and hygienized nutrient-rich water can be applied for various end-use options. One of the challenges for the treated nutrient-rich water, if not used close to the area of treatment, is storage and transportation. In order to address this challenge and diversify the value-added byproducts and end-use options, a nutrient recovery study was carried out using microalgae (Paper V). A preliminary study revealed that the growth of Chlorella sorokiniana with 10% of the treated blackwater as a substrate in a continuous culture resulted in complete uptake of NH4-N and PO4-P. The N and P removal rate at steady state reached up to 99.2 mg NH4-N L-1 d-1 and 8 mg PO4-P L-1 d-1, respectively, with a corresponding average biomass yield on the energy of 0.29 g (mole photons)-1. The 10% treated blackwater substrate, however, had a low concentration of Mg and trace elements essential for microalgae growth. Low concentration of Mg was observed as the limiting factor for using diluted treated blackwater solely as a substrate. Therefore, the supplementation with Mg and trace elements was required. Moreover, the nitrogen in the treated effluent is mainly available as NH4-N. A higher concentration of NH4-N and its oxidation during substrate storage could increase the NO2-N concentration, which inhibited the growth of C. sorokiniana at a concentration of above 50 mg L-1. In conclusion, results from this thesis demonstrated the value of domestic wastewater as a source of alternative nutrient-energy-water resources. The development of an integrated treatment and resource recovery facility for a source-separated sanitation system could provide a healthy local environment, social and economic payback for households and communities, and contribute to green development and food security.Verdens vannspesialister er enige om å arbeide med økt ressursutvinning fra avløpsvann og reduserte utslippene til miljøet. Kildeseparerte avløpsbehandlingssystemer, som gir muligheter for lokal resirkulering og ressursbruk, er et aktuell alternativ til konvensjonell behandling av blandet avløpsvann i sentraliserte behandlingssystemer. Målet med denne undersøkelsen var å undersøke og utvikle en ny og bærekraftig tilnærming der ressursene i avløpsvann behandles, gjenvinnes og gjenbrukes i områder nær opprinnelseskilden. Dette arbeidet omfatter utvikling av tekniske løsninger for behandling av kildeseparert svartvann, samt studier av prosesser knyttet til behandling av svart og grått avløpsvann fra studentboliger med 48 studenter ved Norges Miljø- og Biovitenskaplige Universitet, (NMBU) Ås, Norge. Videre vurderes muligheten for lokal ressursutnyttelse gjennom biogassproduksjon og i produksjon av mikroalgenbiomasse basert på næringsstoffer som gjenvinnes fra avløpsvann. Hovedmålene med dette arbeidet har vært å: i) utvikle en teknisk løsning for kombinert behandling og ressursutvinning i en lukket syklus som skaper muligheter for den sirkulære økonomien; og ii) vurdere effektiviteten av de ulike enhetsprosessene med hensyn til ressursutvinning og gjenværende utslipp. I den første del ble et kompakt renseanelegg for rensing av gråvann med ulike etterpoleringsløsninger, ble undersøkt (Artikkel 1 og 2). Utsortering av svartvann representerte alene en reduksjon i organisk materiale (OM), totalt suspendert stoff (TSS), nitrogen (N) og fosfor (P) på henholdsvis 64%, 75%, 85 og 88%. Behandling av gråvannet ved slamavskilling og biologisk behandling ved umettet filtrering i porøst medium med fastsittende biofilm, samt etterpolering ved filtrering i finsand (Artikkel 1), resulterte i lave utslippskonsentrasjoner: <2mg O2L-1 (BOD); <2mgSS L-1; <0,1mgP L-1 og <5 Escherichia coli (E.coli)100mL-1. Den andre alternative etterpoleringsløsninger ble studert ved filtrering i kolonner fylt med biokull og Filtralite (Artikkel 2). Disse metodene ga også svært lave utslippskonsentrasjoner. Dette viser at biologiske gråvannsrenseanlegg i kombinasjon med etterpolering er en aktuell løsning der utslippskravene er strenge, blant annet i nedbørfeltet til drikkevannskilder og at renset vann kan brukes til vanning av salat og til generell vanning av utearealer, uten restriksjoner. Separering av svartvannet bidrar i stor grad til å oppnå dette. Den andre delen av denne avhandlingen er fokusert på evaluering av et kombinert behandlings- og ressursutvinningsanlegg for kildeseparert svartvann. En hybridreaktor, bestående av et oppstrøms slamteppe og en anaerob baffel reaktor for behandling av kildeseparert svartvann ble evaluert. Effektene i reaktoren ble undersøkt med forskjellig tilførsel (feed pulses) i termer av effektstabilitet, utløpskvaliteter, fjerning av organisk- og partikulært materiale, biogass produksjon og metan utbytte, variasjoner i svartvannet tatt i betrakting (artikkel III). Resultatene viste at total COD-fjerning stabiliserte seg over 78% innen mindre enn 120 dager. Reaktorens konfigurasjon viste seg å gi tilstrekkelig slamlager, væske/faststoff- separasjon og biogass produksjonen som varierte fra 0,52 til 1,16 L d-1 (L reaktorvolum)-1. Ved steady-state varierte metankonsentrasjonen fra 67 - 82% med en gjennomsnittlig konverteringsrate på 0,69 ± 0,2 og 0,73 ± 0,2 g CH4-COD g-1 CODin for reaktor I og reaktor II. Artikkel IV Viser en kombinert strategi for behandling og gjenvinning av næringsstoffer i svartvann som en kilde til plantetilgjengelige næringsstoffer. Anaerobt behandlet svartvann, rikt på NH4-N og PO4-P, ble behandlet i kolonner i en sekvensiell oppstrømnings- og nedstrøm filtrering gjennom granulert aktiv kull, Cocos kull og Polonite. Hydraulisk overflatebelasting ble satt til 600 L m-2 d- 1. Filtrering gjennom aktivt kull fjernet over 80% av det gjenværende organisk materialet, mer enn 90% suspendert faststoff og turbiditet, og frigjorde over 76% NH4-N og 85% PO4-P i væskefasen. Behandlingen fjernet også TCB og E. coli, og oppnådde konsentrasjoner under deteksjonsgrensen etter at en 11 W ultrafiolett lampe (UVC) ble tilført som en integrert del av filtersystemet. Samlet fører denne tilnærmingen til næringsstoffgjenvinning som en næringsløsning, inaktivering av patogener og reduksjon av organiske stoffer. Det behandlede, hygieniserte - og næringsrike vannet kan brukes til ulike formål. En utfordring for det behandlede næringsrike vannet, er lagring og transport. For å løse denne utfordringen og utvide mulighetene for gjenbruk av næringsstoffene ble det utført en studie ved hjelp av mikroalger (artikkel V). En foreløpig studie viste at veksten av Chlorella sorokiniana med 10% av behandlet svartvann som substrat i en kontinuerlig kultur resulterte i fullstendig opptak av NH4-N og PO4- P. Oppnådd N og P-fjerningen ved steady state var 99.2 mg NH4-N L-1 d-1 og 8 mg PO4-P L-1 d-1 med et tilsvarende gjennomsnittlig biomasseutbytte på 0.29 g (mol fotoner)-1. Behandlet svartvann hadde imidlertid en lav konsentrasjon av Mg og sporstoffer som er viktig for mikroalgeveksten. Dette ble observert som en begrensningsfaktor ved å bruke det behandlede svartvannet som eneste vekstsubstratet. Derfor var det nødvendig å supplere substratet med Mg og sporstoffer. Dessuten er nitrogenet i det behandlede svartvannet hovedsakelig i form av NH4-N. En høy konsentrasjon av NH4-N og dets oksidasjon ved lagring vil kunne øke andelen av NO2-N, som ble observert å hemme veksten av Chlorella sorokiniana når konsentrasjonen kom over 50 mg L-1. Som konklusjon viste resultatene fra denne avhandlingen verdiene i avløpsvann som en kilde til alternative NEV ressurser (næringsstoff, energi og vann). Utviklingen av et integrert behandlings- og ressursutvinningsanlegg basert på kildeseparert avløpsvann vil kunne bidra til et sunt lokalt miljø, sosial og økonomisk tilbakebetaling for husholdninger og lokalsamfunn, og bidra til å oppnå en grønn utvikling og matsikkerhet.The Research Council of Norway ; Ecomotive A

Source-separation and on-site wastewater treatment : a combined treatment and resource recovery facility towards a circular economy

The world's water specialists agree to work on increased resource recovery from wastewater and reduced emissions to the environment. Source-separated wastewater treatment systems, which provide opportunities for local recycling and utilization of resources, are appropriate alternatives to conventional treatment of mixed wastewater in centralized treatment systems. This work includes the development of technical solutions for the treatment of source-separated blackwater, as well as studies of processes related to the treatment of black and grey wastewater from student housing inhabiting 48 students at the Norwegian University of Life Sciences (NMBU), Ås, Norway. Furthermore, the possibility of local resource utilization through biogas production and in the production of microalgae biomass based on nutrients recovered from wastewater is assessed. The main objectives of this work have been to i) develop a technical solution for a combined treatment and resource recovery in a closed cycle that creates opportunities for the circular economy, and ii) assess the efficiency of the various unit processes in terms of resource recovery and residual emissions. In the first section, a compacted greywater treatment system with different posttreatment solutions was investigated (Papers I and II). Separation of blackwater alone resulted a reduction in organic matter (OM), total suspended solids (TSS), nitrogen (N) and phosphorus (P) of 64%, 75%, 85 and 88%, respectively. Treatment of the greywater by sludge separation and biological treatment in a porous medium with attached biofilm, and post-treatment by fine sand filtration (Paper I) resulted in low emission concentrations: <2 mg O2 L-1 (BOD); <2 mg TSS L-1; <0.1 mg P L-1 and <5 Escherichia coli (E.coli) 100 mL-1. In a separate experiment, the post-treatment of the biofilter effluent with biochar and fine Filtralite (Paper II) also gave very low emission concentrations. The results showed that biological treatment plant in combination with post-treatment are appropriate solutions where the emission requirements are strict, especially in areas close to drinking water sources and where treated water can be used for watering salads and general irrigation of outdoor areas without restrictions. Separation of the blackwater greatly contributes to this. The second section of this study focused on the development and evaluation of a combined treatment and resource recovery facility for source-separated blackwater. A hybrid reactor, which integrates an up-flow sludge blanket and the anaerobic baffled reactor was developed. The performance of this reactor was tested, as an integrated treatment system for source-separated blackwater. The effects of load and feed pulses on system performance were evaluated in terms of stability, effluent quality, the removal efficiency of organic and suspended particulate matter, biogas production and methane yield (Paper III). The results showed that the total COD removal efficiency stabilized above 78 % within less than 120 days. The configuration of the reactor provided sufficient sludge expansion volume, solid-liquid separation, and biogas production rate ranged from 0.52 to 1.16 L d-1 (L reactor volume)-1. At steady state, the methane concentration ranged from 67 - 82 % with an average conversion rate of 0.69±0.2 and 0.73±0.2 g CH4-COD g-1CODin for reactor I and reactor II, respectively. Paper IV demonstrates a combined blackwater treatment and nutrient-recovery strategy for the recovery of a more dependable source of plant nutrients. The anaerobically treated blackwater effluent, rich in NH4-N and PO4-P, was treated in a sequence of upflow and downflow filtration columns using granular activated carbon, Cocos char and Polonite. The flow rate was set at 600 L m-2 day- 1. Filtration of the anaerobically treated effluent through activated carbon removed over 80% of the residual organic matter, more than 90% of suspended solids and turbidity while releasing more than 76% NH4–N and 85% of PO4–P in the liquid phase. The treatment train also removed total coliform bacteria (TCB) and E. coli, achieving concentrations below the detection limit after the integration of 11 W ultraviolet (UV) light. This integrated technological approach ensured simultaneous nutrient recovery as a nutrient solution, inactivation of indicator organisms, and reduction of organics. The treated and hygienized nutrient-rich water can be applied for various end-use options. One of the challenges for the treated nutrient-rich water, if not used close to the area of treatment, is storage and transportation. In order to address this challenge and diversify the value-added byproducts and end-use options, a nutrient recovery study was carried out using microalgae (Paper V). A preliminary study revealed that the growth of Chlorella sorokiniana with 10% of the treated blackwater as a substrate in a continuous culture resulted in complete uptake of NH4-N and PO4-P. The N and P removal rate at steady state reached up to 99.2 mg NH4-N L-1 d-1 and 8 mg PO4-P L-1 d-1, respectively, with a corresponding average biomass yield on the energy of 0.29 g (mole photons)-1. The 10% treated blackwater substrate, however, had a low concentration of Mg and trace elements essential for microalgae growth. Low concentration of Mg was observed as the limiting factor for using diluted treated blackwater solely as a substrate. Therefore, the supplementation with Mg and trace elements was required. Moreover, the nitrogen in the treated effluent is mainly available as NH4-N. A higher concentration of NH4-N and its oxidation during substrate storage could increase the NO2-N concentration, which inhibited the growth of C. sorokiniana at a concentration of above 50 mg L-1. In conclusion, results from this thesis demonstrated the value of domestic wastewater as a source of alternative nutrient-energy-water resources. The development of an integrated treatment and resource recovery facility for a source-separated sanitation system could provide a healthy local environment, social and economic payback for households and communities, and contribute to green development and food security

Sludge blanket anaerobic baffled reactor for source-separated blackwater treatment

publishedVersio

Nutrient Recovery from Anaerobically Treated Blackwater and Improving Its Effluent Quality through Microalgae Biomass Production

The blackwater stream of domestic wastewater contains energy and the majority of nutrients that can contribute to a circular economy. Hygienically safe and odor-free nutrient solution produced from anaerobically treated source-separated blackwater through an integrated post-treatment unit can be used as a source of liquid fertilizer. However, the high water content in the liquid fertilizer represents a storage or transportation challenge when utilized on agricultural areas, which are often situated far from the urban areas. Integration of microalgae into treated source-separated blackwater (BW) has been shown to effectively assimilate and recover phosphorus (P) and nitrogen (N) in the form of green biomass to be used as slow release biofertilizer and hence close the nutrient loop. With this objective, a lab-scale flat panel photobioreactor was used to cultivate Chlorella sorokiniana strain NIVA CHL 176 in a chemostat mode of operation. The growth of C. sorokiniana on treated source-separated blackwater as a substrate was monitored by measuring dry biomass concentration at a dilution rate of 1.38 d−1, temperature of 37 °C and pH of 7. The results indicate that the N and P recovery rates of C. sorokiniana were 99 mg N L−1d−1 and 8 mg P L−1d−1 for 10% treated BW and reached 213 mg N L−1d−1 and 35 mg P L−1d−1, respectively when using 20% treated BW as a substrate. The corresponding biomass yield on light, N and P on the 20% treated BW substrate were 0.37 g (mol photon)−1, 9.1 g g−1 and 54.1 g g−1, respectively, and up to 99% of N and P were removed from the blackwater.publishedVersio

Feeding Habits and Activity Patterns of Grivet Monkey (Chlorocebus aethiops L.) in Batiero Church Forest, Northern Ethiopia

Grivet monkeys (Chlorocebus aethiops) are restricted to fragmented forests where food and space are limiting factors. The study investigated the feeding and activity patterns of grivet monkeys in Batiero Church Forest, northern Ethiopia, using focal and scan sampling techniques. Both focal and scan animal sessions lasted 15 min, with 5 min rest intervals between sessions. During the early dry season, grivet monkeys mainly fed on Acacia sieberiana (26.5%) and Juniperus procera (17.5%). Dry season food selection was significantly different, J. procera (20.5%), Acacia mearnsii (15.6%), A. sieberiana (14.2%), and Cyperus bulbosus (12.7%). The predominant plant parts eaten were seeds (42.6% and 33.3% in early dry and dry seasons, respectively) followed by leaves (34.5% and 22.5% in early dry and dry seasons, respectively). The activity patterns showed no significant seasonal variation, and the most frequent activity was feeding (33.3% and 32.6%, in early dry and dry seasons, respectively). The preferred food source tree species are threatened, and the survival of the grivet monkeys depends on the conservation of indigenous plants and trees

Nutrient Recovery from Anaerobically Treated Blackwater and Improving Its Effluent Quality through Microalgae Biomass Production

The blackwater stream of domestic wastewater contains energy and the majority of nutrients that can contribute to a circular economy. Hygienically safe and odor-free nutrient solution produced from anaerobically treated source-separated blackwater through an integrated post-treatment unit can be used as a source of liquid fertilizer. However, the high water content in the liquid fertilizer represents a storage or transportation challenge when utilized on agricultural areas, which are often situated far from the urban areas. Integration of microalgae into treated source-separated blackwater (BW) has been shown to effectively assimilate and recover phosphorus (P) and nitrogen (N) in the form of green biomass to be used as slow release biofertilizer and hence close the nutrient loop. With this objective, a lab-scale flat panel photobioreactor was used to cultivate Chlorella sorokiniana strain NIVA CHL 176 in a chemostat mode of operation. The growth of C. sorokiniana on treated source-separated blackwater as a substrate was monitored by measuring dry biomass concentration at a dilution rate of 1.38 d−1, temperature of 37 °C and pH of 7. The results indicate that the N and P recovery rates of C. sorokiniana were 99 mg N L−1d−1 and 8 mg P L−1d−1 for 10% treated BW and reached 213 mg N L−1d−1 and 35 mg P L−1d−1, respectively when using 20% treated BW as a substrate. The corresponding biomass yield on light, N and P on the 20% treated BW substrate were 0.37 g (mol photon)−1, 9.1 g g−1 and 54.1 g g−1, respectively, and up to 99% of N and P were removed from the blackwater