| 1. |
- Jönsson, Håkan, et al.
(author)
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Potential of productive waste management systems in low- income countries
- 2014
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In: Urban and peri-urban farming in low income countries – challenges and knowledge gaps. - 9789157692306 ; :2014:4, s. 22-26
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Book chapter (peer-reviewed)abstract
- In low- and middle-income countries, often neither waste nor wastewater are fully collected and treated, resulting in major impacts on the environment and health. Urban and peri-urban agriculture provides both food and income to many urban poor, but productivity of land is decreasing. Tackling these problems simultaneously enables solutions for both issues by introducing systems where organic waste is turned into high-value products and safe fertilisers.
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| 2. |
- Niwagaba, Charles, et al.
(author)
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Experiences on the implementation of a pilot grey water treatment and reuse based system at a household in the slum of Kyebando-Kisalosalo, Kampala
- 2014
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In: Journal of Water Reuse and Desalination. - : IWA Publishing. - 2220-1319 .- 2408-9370. ; 4, s. 294-307
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Journal article (peer-reviewed)abstract
- Grey water constitutes the largest fraction of domestic wastewater. It causes environmental sanitation and pollution problems if it is not managed well. If treated, grey water can be a resource for a variety of uses. A pilot system was constructed in February 2013 to treat grey water from a four-member household for sub-surface irrigation of local vegetables. A hydraulic loading rate (HLR) of 60 L m(-2)d(-1) and an organic loading rate (OLR) of 519-1,580 g BOD(5)m(-2)d(-1) were implemented on a multi-media filter of gravel, charcoal, geotextile and mulch (charcoal being the predominant layer) operated as a batched type-system, with a 36-hour retention time. The system was operated for 3 months, during which it showed remarkable removal efficiencies of 90.8 +/- 5.4 and 96.1 +/- 3.0% after 36 hours for chemical oxygen demand (COD) and biochemical oxygen demand (BOD), respectively, and 95 +/- 3.1% for faecal coliforms (FC). The removal efficiencies at 36 hours, of total nitrogen (TN), total phosphorus (Tot-P), total suspended solids (TSS) and total dissolved solids (TDS) were 39.0, 30.1, 85.2 and 78.6%, respectively. Plant response to sub-surface irrigation with treated grey water was largely masked by rainy season and the effluent had a limited effect on the soil.
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| 3. |
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| 4. |
- Jönsson, Håkan, et al.
(author)
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Återvinn fler näringsämnen än fosfor i avloppsvatten
- 2012
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In: Dagens nyheter. - 1101-2447. ; ?, s. 6-
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Other publication (pop. science, debate, etc.)abstract
- För att minska utsläppen av växthusgaser bör vi återvinna fler växtnäringsämnen ur avloppsslammet. Regeringens ensidiga fokus på fosfor i detta avseende riskerar att skada det långsiktiga miljöarbetet. Vi vill skärpa miljömålen och inkludera även ämnen som kväve, kalium och svavel, skriver professorer och forskare från SLU.
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| 5. |
- Egenvall, Agneta, et al.
(author)
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Rein tension in harness trotters during on-track exercise
- 2022
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In: Frontiers in Veterinary Science. - : Frontiers Media SA. - 2297-1769. ; 9
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Journal article (peer-reviewed)abstract
- Horseracing is under public scrutiny with increasing demands to safeguard horse welfare. It is accepted that, as a result of bit pressure and/or equipment, mouth lesions accompany many types of horse use, including racing. However, there are currently no data available on the range of bit pressures in driven trotters. Our aim was to investigate whether rein tension (RT, proxy for bit pressures) differs among gaits, between tempo within gait, between horses and drivers, and between left/right reins. Standardbreds (n = 9), driven by experienced drivers (n = 11), performed exercise tests on a racetrack (cross-over design; total 31 tests, data available from 26 tests). Horses' motion symmetry was measured before tests (trotting in hand). Rein tension, speed and heart rate were measured during exercise. A moving-window filter was applied to RT raw data. Median, maximum and interquartile range for the estimated stride median RT were determined for each rein (left/right) and segment: walk; circling in slow trot followed by transition to faster trot; fast (racing) trot; and slowing down to walk. Mixed models were used for statistical analysis. Least square means for segment median RT ranged between 17–19 N in walk, 34–40 N during circling-accelerating, 51–62 N in fast trot, and 53–71 N for slowing down. Segment maximum RT was between 60–81 N in walk, 104–106 N during circling-accelerating, 72–86 N in fast trot, and 86–129 N during slowing down. Interquartile ranges were between 7–9 N in walk, 28–31 N during circling-accelerating, 8–10 N in fast trot, and 12–18 N for slowing down. Hind limb asymmetry exceeded the recommended threshold in three horses and was associated with higher median (48 N) and maximum (106 N) RT than symmetric horses (29 N and 73 N, respectively, p < 0.01). Consistent left-right asymmetry in RT was more common among horses than among drivers. Rein tension increased with increasing heart rate (p ≤ 0.0006). Rein tensions were higher than those reported during riding or in horses worked from the ground. The findings of high RT, taken together with the high reported prevalence of oral injuries in harness trotters, call for further research into RT, motion symmetry and use of equipment.
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| 6. |
- Jönsson, Håkan, et al.
(author)
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System för återföring av fosfor i källsorterade fraktion av urin, fekalier, matavfall och i liknande rötat samhälls- och lantbruksavfall
- 2013
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Reports (other academic/artistic)abstract
- Rapporten behandlar system för återföring av fosfor från källsorterade fraktioner av urin, fekalier och matavfall, samt teknik för att omfördela fosfor från djurgårdar med fosforöverskott till gårdar med underskott. Arbetet har finansierats av Naturvårdsverket inom regeringsuppdraget M2012/317/Ke Uppdrag om hållbar återföring av fosfor. Rapporten belyser effekter på Giftfri miljö och God bebyggd miljö och i viss mån klimatpåverkan och energianvändning. Större delen av fosforn i gödsel och rötrest kan med befintlig teknik (centrifug eller skruvpress) separeras ut i en fast fraktion vars vikt endast är ca 10 % av det urspungliga materialets. Detta underlättar transport av fosfor från gårdar med överskott till gårdar med brist. Genom effektivt stöd till införandet av denna teknik bör fördelningen av fosfor i jordbruket snabbt kunna förbättras. Klosettvatten‐(KL‐)sortering, d.v.s. att toalettavlopp samlas separat, hygieniseras och återförs som gödsel, kan väsentligt förbättra återföringen av växtnäring från avlopp och ger samtidigt flera andra miljöfördelar. Kadmium‐fosforkvoten i källsorterat KL‐vatten är 11‐13 mg kadmium per kg fosfor, vilket är lägre än i naturgödsel. Införande av KL‐system ger en kraftig reduktion av spridningen av humanpatogener och antibiotikaresistenta bakterier till miljön. Systemet minskar också utsläpp av hormoner och läkemedelsrester liksom av övergödande ämnen till vatten, speciellt vid bräddning. Införandet av KL‐sortering skulle totalt sett minska utsläpp av växthusgaser och användningen av energi och dessutom ge god potential för sambehandling med matavfall. Systemet passar i storstad och i glesbygd. Det finns redan ca 122 000 anläggningar med slutna tankar i Sverige och det källsorterade KL‐vattnet från dessa kan snabbt återföras till kretsloppet. Källsorterad urin har låga tungmetallhalter, kadmium‐fosforkvoten är endast 0,3‐2 mg kadmium per kg fosfor. Urinsortering ger synergier i form av stor reduktion av hormoner och läkemedelsrester och minskade utsläpp av övergödande ämnen till vatten, speciellt vid bräddning. Utsläppen av växthusgaser och energianvändningen minskar, men synergierna är mindre än för KL‐sortering, då spridningen av humanpatogener knappt påverkas och sambehandling med matavfall inte är trolig. Källsorterat matavfall från hushåll har en högre kadmium‐fosforkvot (ca 37 mg kadmium per kg fosfor) än källsorterad urin eller KL‐vatten, men matavfall från andra källor, t.ex. livsmedelshandel, är troligen renare. Mängden fosfor som återförs med rötat matavfall är redan idag lika stor som den skulle bli om KL‐vattnet från alla befintliga tankar återfördes till lantbruk och utbyggnadstakten är hög. Det finns stora möjligheter till synergi med KL‐system genom samhantering och –behandling. Gödsel från källsorterade produkter bedöms ha god acceptans. För att öka återföringen av källsorterad avloppsnäring behövs organisatoriska förbättringar, information, utbildning om kretsloppssystem och ett miljömål som inkluderar kväve.
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| 7. |
- Nordin, Annika, et al.
(author)
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Pathogen and indicator inactivation in source-separated human urine heated by the sun
- 2013
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In: Journal of Water, Sanitation and Hygiene for Development. - : IWA Publishing. - 2043-9083 .- 2408-9362. ; 3, s. 181-188
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Journal article (peer-reviewed)abstract
- Source-separation of urine enables energy-efficient recycling of large quantities of high quality plant nutrients from the wastewater system to food production. To manage the risk of diseases transmission the urine should be sanitised, which is commonly done by storage. The sanitisation of urine at three ambient exposures, resulting in fluctuating storage temperatures, was studied in 10 L plastic jerry cans in Kampala, Uganda. Follow-up studies using similar temperature cycles were performed under laboratory conditions. Daily mean mid-point temperature in jerry cans in full sun, adjacent to a wall and indoors was 24, 24 and 22 degrees C (amplitude 7.5, 4.7 and 1.2 degrees C), respectively. In urine stored at full sun (total ammonia nitrogen 4 +/- 1.5 g L-1, pH 9) Escherichia coli, Salmonella and Enterococcus spp. (initially 10(5)-10(6) cfu mL(-1)) were not detected (<10(1) cfu mL(-1)) after 11 h, 14 h and 50 d, respectively. No viable Ascaris suum eggs were found after 40 d. The t(90) for enterobacteria phage MS2, coliphage Phi X 174 and Salmonella typhimurium phage 28B in sun-exposed cans was 8.2, 37 and 55 d respectively. Fluctuating temperatures in combination with ammonia gave faster inactivation of bacteria and Ascaris suum eggs than the same constant mean temperature.
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| 8. |
- Gren, Ing-Marie, et al.
(author)
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Costs of air pollutants from shipping : a meta-regression analysis
- 2020
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In: Transport reviews. - : Taylor & Francis. - 0144-1647 .- 1464-5327. ; 40:4, s. 411-428
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Journal article (peer-reviewed)abstract
- This study estimated the external cost of air pollution from shipping by means of a meta-regression analysis, which has not been made before. Three pollutants, which were included in most of the primary studies, were considered: nitrogen oxides (NOx), sulphur dioxides (SO2) and particulate matters with a diameter of max 2.5 micrometres (PM2.5). All primary studies included damages of health and a majority added impacts on agriculture and estimated the cost of air pollutants by transferring cost estimates from studies on costs of air emissions from transports in Europe. Different regression models and estimators were used and robust results were found of statistically significant emission elasticities of below one, i.e. total external costs increase by less than 1% when emissions increase by 1%. There was a small variation between the pollutants, with the highest elasticity for PM2.5 and lowest for NOx. Calculations of the marginal external cost of the pollutants showed the same pattern, with this cost being approximately six times higher for PM2.5 than for the other pollutants. Common to all pollutants was that the marginal external cost decreases when emission increases. Another robust result was a significant increase in the cost of studies published in journals compared with other publication outlets. These findings point out some caution when transferring constant external unit cost of air pollutant from shipping, which is much applied in the literature, and the cost functions estimated in this study could thus provide a complementary transfer mechanism.
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| 9. |
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| 10. |
- Eriksson, Ola
(author)
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An integrated multi-criteria decision analysis and optimization modeling approach to spatially operational road repair decisions
- 2021
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In: Canadian Journal of Forest Research. - : Canadian Science Publishing. - 0045-5067 .- 1208-6037. ; 51, s. 465-483
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Journal article (peer-reviewed)abstract
- In this study, we developed a generic cost-effective approach for spatially explicit decision support involving the allocation of road repair treatments. The approach begins with an assessment of the existing road condition to identify the extent of environmental impacts and to determine road repair regimes in a subjective manner using group-decision making efforts. An integer programming model is then formulated by combining expert opinions with operational costs to guide repair schedules required for each road segment at the operational planning level. To demonstrate model performance, we applied it to a 400 km(2) landscape consisting of 289 km of paved roads in the mountainous region of the Hyrcanian forests in Iran. We assessed sensitivity of the inputs, such as weight verification, budgetary limitations, and rehabilitation weights. The results of the subjective analysis show that 76% of the roads analyzed in these forests must be prioritized to receive treatments as intended for logistical purposes. Incorporating the extent of environmental dimensions into operational costs allows us to generate an optimal tradeoff curve by selecting an appropriate treatment for segments of a road network. The approach demonstrated here can be used to design detailed alternative solutions for addressing spatially-informed road decisions under various terrain conditions.
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