Sludge Treatment Reed Beds (STRBs) are widely used in Northern Europe to dewater and mineralize surplus sludge from activated sludge systems used to treat urban domestic sewage. STRBs are ...low-technology, energy-efficient, and do not require addition of chemicals. They dewater and stabilize the sludge and produce a final product that can be safely used as a fertilizer for agricultural crops. Long-term sludge reduction takes place in the reed beds due to dewatering and mineralization of the organic matter in the sludge. Although, in theory, a simple technique relying largely on natural processes, experience has shown that it is very important to understand and respect the basic design and operation requirements of STRBs. This paper describes the basic design and operation requirements of STRBs, with special focus on pivotal requirements to respect in order to secure proper functioning. Also, the paper summarizes performance experience concerning final dry matter content, degree of mineralization, emission of greenhouse gases, and degradation of micro-pollutants in STRBs. There are still a number of outstanding issues that are not fully understood, particularly in relation to the importance of the sludge quality for the dewatering in an STRB. Therefore, extreme care should be taken when attempting to extrapolate the use of STRBs to applications and regions outside of their ‘normal’ and documented area of application.
Iron is present in all types of wastewater; however, besides acid mine drainage, where it is a major constituent of concern, it is usually neglected in other types of wastewaters. In all kinds of ...constructed wetlands, iron plays important role in removal of organics and phosphorus, and it has an impact on transformation of nitrogen, sulfur, and metals. The biogeochemistry of iron is well understood in natural wetlands, but knowledge about iron impact on microbiological and chemical transformations during wastewater treatment in constructed wetlands is very limited. So far, the sparse research in this area provides limited information on observed interactions with several varying parameters across the studies, making it difficult to draw fundamental and mechanistic conclusions. A critical review of the complex biogeochemical networking of iron in CWs is therefore necessary to fill the gap in knowledge on the role of iron and its biogeochemical multi-interactions in wastewater treatment processes of CWs. This review is the first with specific focus on iron, discussing its mitigation and retention in CWs with different configurations and operational strategies, and presenting both seasonal dynamics and the potential remobilization of Fe. It also comprehensively discusses the interactions of redox-controlled iron turnover with the biogeochemical processes of other elements, for example, carbon (C), nitrogen (N), phosphorus (P), sulfur (S), and heavy metals. The health response of wetland plants to both deficiency and toxicity of Fe in CWs designed with specific treatment targets has also been evaluated. Due to the complexity of various wastewater compositions and microredox gradients in the root rhizosphere in CWs, future research needs have also been identified.
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IJS, KILJ, NUK, PNG, UL, UM
The knowledge on the performance enhancement of nitrogen and organic matter in the expanded constructed wetlands (CWs) with various new designs, configurations, and technology combinations are still ...not sufficiently summarized. A comprehensive review is accordingly necessary for better understanding of this state-of-the-art-technology for optimum design and new ideas. Considering that the prevailing redox conditions in CWs have a strong effect on removal mechanisms and highly depend on wetland designs and operations, this paper reviews different operation strategies (recirculation, aeration, tidal operation, flow direction reciprocation, and earthworm integration), innovative designs, and configurations (circular-flow corridor wetlands, towery hybrid CWs, baffled subsurface CWs) for the intensifications of the performance. Some new combinations of CWs with technologies in other field for wastewater treatment, such as microbial fuel cell, are also discussed. To improve biofilm development, the selection and utilization of some specific substrates are summarized. Finally, we review the advances in electron donor supply to enhance low C/N wastewater treatment and in thermal insulation against low temperature to maintain CWs running in the cold areas. This paper aims to provide and inspire some new ideas in the development of intensified CWs mainly for the removal of nitrogen and organic matter. The stability and sustainability of these technologies should be further qualified.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
The objective of this trial was to assess the long-term effect of the CHANGE lifestyle coaching intervention for 428 people with abdominal obesity and schizophrenia spectrum disorders on ...cardiovascular risk. In this randomized, superiority, multi-center clinical trial, participants were randomized to 12 months of either lifestyle coaching plus care coordination (N = 138), care coordination alone, (N = 142) or treatment as usual (N = 148). There was no effect after 12 months, but we hypothesized that there might have been a delayed treatment effect. Our primary outcome at two-year follow-up was 10-year risk of cardiovascular disease standardized to 60 years of age. After two-years the mean 10-year cardiovascular-disease risk was 8.7% (95% confidence interval (CI) 7.6-9.9%) in the CHANGE group, 7.7% (95% CI 6.5-8.9%) in the care coordination group, and 8.9% (95% CI 6.9-9.2%) in the treatment as usual group (P = 0.24). Also, there were no intervention effects for any secondary or exploratory outcomes, including cardiorespiratory fitness, weight, physical activity, diet and smoking. No reported adverse events could be ascribed to the intervention. We conclude that there was neither any direct nor any long-term effect of individual lifestyle coaching or care coordination on cardiovascular risk factors in people with abdominal obesity and schizophrenia spectrum disorders. The trial was approved by the Ethics Committee of Capitol Region Copenhagen, Denmark (registration number: H-4-2012-051) and the Danish Data Protection Agency (registration number: 01689 RHP-2012-007). The trial was funded by the Mental Health Services of the Capital Region of Denmark, the Lundbeck Foundation, the Tryg Foundation, the Danish Ministry of Health, and the Dæhnfeldts Foundation.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Life expectancy in patients with schizophrenia is reduced by 20 years for men and 15 years for women compared to the general population. About 60% of the excess mortality is due to physical ...illnesses, with cardiovascular disease being dominant. CHANGE was a randomized, parallel‐group, superiority, multi‐centre trial with blinded outcome assessment, testing the efficacy of an intervention aimed to improve cardiovascular risk profile and hereby potentially reduce mortality. A total of 428 patients with schizophrenia spectrum disorders and abdominal obesity were recruited and centrally randomized 1:1:1 to 12 months of lifestyle coaching plus care coordination plus treatment as usual (N=138), or care coordination plus treatment as usual (N=142), or treatment as usual alone (N=148). The primary outcome was 10‐year risk of cardiovascular disease assessed post‐treatment and standardized to age 60. At follow‐up, the mean 10‐year risk of cardiovascular disease was 8.4 ± 6.7% in the group receiving lifestyle coaching, 8.5 ± 7.5% in the care coordination group, and 8.0 ± 6.5% in the treatment as usual group (p=0.41). We found no intervention effects for any secondary or exploratory outcomes, including cardiorespiratory fitness, physical activity, weight, diet and smoking. In conclusion, the CHANGE trial did not support superiority of individual lifestyle coaching or care coordination compared to treatment as usual in reducing cardiovascular risk in patients with schizophrenia spectrum disorders and abdominal obesity.
Background: Serious mental illness (SMI) reduces life expectancy, primarily due to somatic comorbidity linked to obesity. Meta-analyses have found beneficial effects of lifestyle interventions in ...people with SMI and recommended their implementation to manage obesity. Objective: The objective of this systematic review was to assess the benefits and harms of individualized lifestyle interventions for weight in people diagnosed with SMI and to explore potential mediators and moderators of the effect. Methods: The protocol was registered at PROSPERO (CRD42016049093). Randomized clinical trials (RCTs) assessing the effect of individualized lifestyle interventions on weight management in people with SMI were included. Primary outcomes were differences in endpoint body mass index (BMI) and the proportion achieving clinically relevant weight loss (≥5%). Secondary outcomes included quality of life, cardiometabolic risk factors, and adverse effects. Results: We included 41 RCTs (n = 4,267). All trials were at high risk of bias according to the Cochrane Handbook for Systematic Reviews of Interventions. The experimental interventions reduced the mean difference in BMI by –0.63 kg/m 2 (95% confidence interval CI = –1.02 to –0.23; p = 0.002; I 2 = 70.7%) compared to the control groups. At postintervention follow-up (17 RCTs), the effect size remained similar but was no longer significant (BMI = –0.63 kg/m 2 ; 95% CI = –1.30 to 0.04; p = 0.07; I 2 = 48.8%). The risk ratio for losing ≥5% of baseline weight was 1.51 (95% CI = 1.07–2.13; p = 0.02) compared to the control groups. GRADE showed very low or low quality of evidence. Conclusion: There is a statistically significant, but clinically insignificant, mean effect of individualized lifestyle interventions for weight reduction in people with SMI.
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BFBNIB, NMLJ, NUK, PNG, UL, UM, UPUK
The effects of inorganic nitrogen (N) source (NH
4
+, NO
3
− or both) on growth, biomass allocation, photosynthesis, N uptake rate, nitrate reductase activity and mineral composition of
Canna indica ...were studied in hydroponic culture. The relative growth rates (0.05–0.06
g
g
−1
d
−1), biomass allocation and plant morphology of
C. indica were indifferent to N nutrition. However, NH
4
+ fed plants had higher concentrations of N in the tissues, lower concentrations of mineral cations and higher contents of chlorophylls in the leaves compared to NO
3
− fed plants suggesting a slight advantage of NH
4
+ nutrition. The NO
3
− fed plants had lower light-saturated rates of photosynthesis (22.5
μmol
m
−2
s
−1) than NH
4
+ and NH
4
+/NO
3
− fed plants (24.4–25.6
μmol
m
−2
s
−1) when expressed per unit leaf area, but similar rates when expressed on a chlorophyll basis. Maximum uptake rates (
V
max) of NO
3
− did not differ between treatments (24–35
μmol
N
g
−1
root
DW
h
−1), but
V
max for NH
4
+ was highest in NH
4
+ fed plants (81
μmol
N
g
−1
root
DW
h
−1), intermediate in the NH
4NO
3 fed plants (52
μmol
N
g
−1
root
DW
h
−1), and lowest in the NO
3
− fed plants (28
μmol
N
g
−1
root
DW
h
−1). Nitrate reductase activity (NRA) was highest in leaves and was induced by NO
3
− in the culture solutions corresponding to the pattern seen in fast growing terrestrial species. Plants fed with only NO
3
− had high NRA (22 and 8
μmol
NO
2
−
g
−1
DW
h
−1 in leaves and roots, respectively) whereas NRA in NH
4
+ fed plants was close to zero. Plants supplied with both forms of N had intermediate NRA suggesting that
C. indica takes up and assimilate NO
3
− in the presence of NH
4
+. Our results show that
C. indica is relatively indifferent to inorganic N source, which together with its high growth rate contributes to explain the occurrence of this species in flooded wetland soils as well as on terrestrial soils. Furthermore, it is concluded that
C. indica is suitable for use in different types of constructed wetlands.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Official guidelines for the on-site treatment of domestic sewage have recently been published by the Danish Ministry of Environment as a consequence of new treatment requirements for single houses ...and dwellings in rural areas. This paper summarises the guidelines for vertical constructed wetland systems (planted filter beds) that will fulfil demands of 95% removal of BOD and 90% nitrification. The system can be extended with chemical precipitation of phosphorus with aluminium polychloride in the sedimentation tank to meet requirements of 90% phosphorus removal. The necessary surface area of the filter bed is 3.2
m
2/person equivalent and the effective filter depth is 1.0
m. The filter medium must be filtersand with a
d
10 between 0.25 and 1.2
mm, a
d
60 between 1 and 4
mm, and a uniformity coefficient (
U
=
d
60/
d
10) less than 3.5. The sewage is, after sedimentation, pulse-loaded onto the surface of the bed using pumping and a network of distribution pipes. The drainage layer in the bottom of the bed is passively aerated through vertical pipes extending into the atmosphere in order to improve oxygen transfer to the bed medium. Half of the nitrified effluent from the filter is recirculated to the first chamber of the sedimentation tank or to the pumping well in order to enhance denitrification and to stabilise the treatment performance of the system. A phosphorus removal system is installed in the sedimentation tank using a small dosing pump. The mixing of chemicals is obtained by a simple airlift pump, which also circulates water in the sedimentation tank. The vertical flow constructed wetland system is an attractive alternative to the common practice of soil infiltration and provides efficient treatment of sewage for discharge into the aquatic environment.
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► Effect of aquatic plants on the removal capacity of emerging contaminants was studied. ► Microcosm study revealed that plants aid to the removal of these contaminants. ► Removal ...efficiencies ranged from no detectable removal to more than 99 %. ► Biodegradation, plant uptake and photodegradation are the most important removal pathways. ► The concentration decline was fit to a pseudo-first order kinetic.
Microcosm wetland systems (5 L containers) planted with Salvinia molesta, Lemna minor, Ceratophyllum demersum, and Elodea canadensis were investigated for the removal of diclofenac, triclosan, naproxen, ibuprofen, caffeine, clofibric acid and MCPA. After 38days of incubation, 40–99% of triclosan, diclofenac, and naproxen were removed from the planted and unplanted reactors. In covered control reactors no removal was observed. Caffeine and ibuprofen were removed from 40% to 80% in planted reactors whereas removals in control reactors were much lower (2–30%). Removal of clofibric acid and MCPA were negligible in both planted and unplanted reactors. The findings suggested that triclosan, diclofenac, and naproxen were removed predominantly by photodegradation, whereas caffeine and naproxen were removed by biodegradation and/or plant uptake. Pseudo-first-order removal rate constants estimated from nonlinear regressions of time series concentration data were used to describe the contaminant removals. Removal rate constants ranged from 0.003 to 0.299d−1, with half-lives from 2 to 248days. The formation of two major degradation products from ibuprofen, carboxy-ibuprofen and hydroxy-ibuprofen, and a photodegradation product from diclofenac, 1-(8-Chlorocarbazolyl)acetic acid, were followed as a function of time. This study emphasizes that plants contribute to the elimination capacity of microcontaminants in wetlands systems through biodegradation and uptake processes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK
Removal efficiencies and elimination kinetics of 13 pharmaceuticals and personal care products (PPCPs) and BOD5, TSS, and ammonium were evaluated in a pilot vertical subsurface-flow constructed ...wetland (VFCW) and compared with those obtained by a sand filter. On the basis of the observed removals, the PPCPs studied were grouped in relation to their removal efficiency into (i) PPCPs very efficiently removed, that is, >95% removal in one of the systems (caffeine, salicylic acid, methyl dihydrojasmonate, CA-ibuprofen, hydrocinnamic acid, oxybenzone, ibuprofen, OH-ibuprofen); (ii) PPCPs moderately removed, with removals between 70 and 90% in the two systems (naproxen, diclofenac, galaxolide, and tonalide); and finally (iii) PPCPs poorly removed, with elimination rates of <30% (carbamazepine). At design hydraulic loading rate (HLR) the planted VFCW and the nonplanted SF exhibited similar PPCP removal efficiencies, but the VFCW was less sensitive to removal decline in overloading conditions (up to 2 times the design HLR). Moreover, under a clogging simulation, the HLR and the presence of vegetation were some of the key aspects affecting the PPCPs, BOD5, and ammonium removal from domestic wastewater. The VFCW evaluated was more efficient in terms of removal efficiency and loading rate for most of the PPCPs studied in comparison to constructed wetlands of other configurations (i.e., horizontal subsurface flow) and SF (nonplanted). The shorter hydraulic residence time (a few hours) in VFCW compared to that in other CW configurations ranging from days to weeks makes VFCWs a very appropriate wastewater treatment option in space-limited areas.
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