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1.
The green microalga Dictyosphaerium chlorelloides was identified as promising microorganism for biotechnological production of exopolysaccharides (EPS). In stationary phase the culture suspension solidifies to thick gel, with very high viscosity and high content of EPS which may be interesting for many biotechnological applications. To develop cultivation protocol for maximum biomass/polysaccharide production, the optimum conditions for growth and polysaccharides production were determined in this study using the crossed gradient cultivation method. Temperature and irradiance requirements of Dictyosphaerium chlorelloides were evaluated by statistical analyses for growth rate/biomass, extracellular (EPS) and intracellular (IPS) polysaccharides contents in crossed gradients of temperature (4–45°C) and irradiance (2–18 W/m 2, 9.1 – 82.3 μmol/(m 2 s)). The maximum relative growth rate was observed at temperatures around 19.2°C and relatively low irradiances in range 2.6–11 W/m 2 (11.9–50.3 μmol/(m 2 s)). The maximum IPS production was observed at temperatures around 19.2°C and irradiance around 11 W/m 2 (50.3 μmol/(m 2 s)). The maximum production of EPS was observed at temperatures around 25.7°C and similar irradiances as IPS production. Due to temperature separation of growth and EPS production, development of cultivation protocol based controlled temperature manipulation is possible. 相似文献
2.
A novel approach to Cr(VI)-contaminated wastewater treatment was investigated using microbial fuel cell technologies in fed-batch
mode. By using synthetic Cr(VI)-containing wastewater as catholyte and anaerobic microorganisms as anodic biocatalyst, Cr(VI)
at 100 mg/l was completely removed during 150 h (initial pH 2). The maximum power density of 150 mW/m 2 (0.04 mA/cm 2) and the maximum open circuit voltage of 0.91 V were generated with Cr(VI) at 200 mg/l as electron acceptor. This work verifies
the possibility of simultaneous electricity production and cathodic Cr(VI) reduction. 相似文献
3.
Various behavioural and physiological tests were applied to determine whether an aluminised modified zeolite clay product
(Z2G1), used to cap phosphorus release from lake sediments, had sub-lethal effects on adult freshwater crayfish ( Paranephrops planifrons). In situ exposures of caged crayfish before and after application of modified zeolite to Lake Okaro, Central North Island,
New Zealand, at a nominal application concentration of 350 g m −2, did not impact the survival of freshwater crayfish or produce any significant sub-lethal effects on crayfish mobility or
physiology that we could detect. In laboratory sediment tests, crayfish did not show any consistent effect from short-term
(10 days) exposure to modified zeolite (at concentrations of 350, 700 or 2,100 g m −2) or to alum. When combined, the field and laboratory data provide strong evidence that applications of 350 g m −2 modified zeolite will have no short-term effect on adult crayfish, with a ‘margin of safety’ for higher application rates.
Chronic exposure effects of capping agents and the indirect impacts of lake treatment (e.g. food web responses) are yet to
be determined. Quantitative measures of shade- and shelter-seeking behaviour, righting behaviour, and length of escape response,
could be improved by the addition of standardised behavioural observations. Physiological measures of ammoniacal-N production
and oxygen consumption are less variable than behavioural tests, but comparisons between treatments are best conducted simultaneously.
A suite of behavioural and physiological sub-lethal measures using field and laboratory exposures is recommended to provide
an integrated assessment of crayfish health. 相似文献
4.
A low-cost floating photobioreactor (PBR) without the use of aeration and/or an agitation device, in which carbon was supplied in the form of bicarbonate and only wave energy was utilized for mixing, was developed in our previous study. Scaling up is a common challenge in the practical application of PBRs and has not yet been demonstrated for this new design. To fill this gap, cultivation of Spirulina platensis was conducted in this study. The results demonstrated that S. platensis had the highest productivity at 0.3 mol L−1 sodium bicarbonate, but the highest carbon utilization (104 ± 2.6%) was obtained at 0.1 mol L−1. Culture of Spirulina aerated with pure oxygen resulted in only minor inhibition of growth, indicating that its productivity will not be significantly reduced even if dissolved oxygen is accumulated to a high level due to intermittent mixing resulting from the use of wave energy. In cultivation using a floating horizontal photobioreactor at the 1.0 m2 scale, the highest biomass concentration of 2.24 ± 0.05 g L−1 was obtained with a culture depth of 5.0 cm and the highest biomass productivity of 18.9 g m−2 day−1 was obtained with a depth of 10.0 cm. This PBR was scaled up to 10 m2 (1000 L) with few challenges; biomass concentration and productivity during ocean testing were little different than those at the 1.0 m2 (100 L) scale. However, the larger PBR had an apparent carbon utilization efficiency of 45.0 ± 2.8%, significantly higher than the 39.4 ± 0.9% obtained at the 1 m2 scale. These results verified the ease of scaling up floating horizontal photobioreactors and showed their great potential in commercial applications. 相似文献
5.
During summer 2007, Arctic microphytobenthic potential primary production was measured at several stations around the coastline
of Kongsfjorden (Svalbard, Norway) at ≤5 m water depth and at two stations at five different water depths (5, 10, 15, 20,
30 m). Oxygen planar optode sensor spots were used ex situ to determine oxygen exchange in the overlying water of intact sediment
cores under controlled light (ca. 100 μmol photons m −2 s −1) and temperature (2–4°C) conditions. Patches of microalgae (mainly diatoms) covering sandy sediments at water depths down
to 30 m showed high biomass of up to 317 mg chl a m −2. In spite of increasing water depth, no significant trend in “photoautotrophic active biomass” (chl a, ratio living/dead cells, cell sizes) and, thus, in primary production was measured at both stations. All sites from ≤5 to
30 m water depth exhibited variable rates of net production from −19 to +40 mg O 2 m −2 h −1 (−168 to +360 mg C m −2 day −1) and gross production of about 2–62 mg O 2 m −2 h −1 (17–554 mg C m −2 day −1), which is comparable to other polar as well as temperate regions. No relation between photoautotrophic biomass and gross/net
production values was found. Microphytobenthos demonstrated significant rates of primary production that is comparable to
pelagic production of Kongsfjorden and, hence, emphasised the importance as C source for the zoobenthos. 相似文献
6.
Regional variability in the annual fluxes of particulate organic carbon (POC) and biogenic silica (Si) at the periphery of
the Mackenzie Shelf (Beaufort Sea) was investigated using eight long-term sediment traps moored at ~100-m depth. Relatively
high autochthonous POC and Si fluxes were recorded in the Mackenzie Trough (4.1 and 8.9 g m −2 year −1 respectively) and off Cape Bathurst (6.6 and 79 g m −2 year −1), two areas where upwelling events are frequently observed. Diatomaceous new production was minimum on the mid-slope of the
Mackenzie Shelf (2.8 g C m −2 year −1), moderate in the Mackenzie Trough (14.5 g C m −2 year −1), and highest off Cape Bathurst (128.7 g C m −2 year −1). High annual autochthonous POC flux corresponded to high diatom production. Among sites, the vertical attenuation of the
POC flux increased with diatomaceous new production. Hence, the retention of autochthonous POC in the surface layer (<100 m)
was highest (95%) at the highly productive site off Cape Bathurst, intermediate (72%) in the moderately productive Mackenzie
Trough, and low (4%) at the unproductive mid-slope of the shelf. Our results indicate that, on Arctic shelves, upwelling and
the production of diatoms increase the fraction of the POC which is retained in the surface layer and diverted to the pelagic
food web. In the relatively unproductive waters of the Arctic Ocean, biological hot spots such as the one identified off Cape
Bathurst where the food web promotes retention rather than vertical export could be disproportionately important as feeding
grounds for higher trophic levels. 相似文献
7.
Livestock are the major consumers of water but also sustain millions of pastoralist and farming families. In regions where
water is a scarce commodity, such as the Nile basin, there is a need for strategies to improve livestock water productivity
(LWP). This study seeks to contribute to this need through a better understanding of livestock water use and productivity
within the Nile basin and how this varies across the basin. We developed a spatial framework combining dynamic models of digestion
in ruminants, crop water requirements (CWRs), and animal drinking water requirements to estimate spatial distribution of livestock
water requirements in different livestock production systems (LPSs). We compared this with livestock production and water
availability estimates within the basin. The results show that in most areas LWP is less than 0.1 USD/m 3, with only few areas showing a LWP of 0.5 USD/m 3 and higher. This is largely related to very low livestock meat and milk production on one hand and very variable, but, in
general, low feed water productivity (fWP). Total water need for feed production was estimated to be roughly 94 billion m 3, which amounts to approximately 5% of the total annual rainfall (68 billion m 3 or 3.6% of total annual rainfall when excluding water for residues). Differences in LWP between systems and regions are large,
suggesting considerable scope for improvements. We discuss the main factors influencing observed patterns of LWP and livestock
water use and how this information can be used for developing strategies for increasing the water productivity of agricultural
systems at the basin level. 相似文献
8.
In situ paired light and dark-stirred benthic flux chambers were used to estimate dissolved oxygen flux across the sediment–water interface in Lake Mývatn, Iceland. Three sampling stations were selected, each station reflecting a specific sedimentary environment, benthic communities, and water depth. During this study the phytoplankton density was low. Spatial and seasonal variations of bottom DO concentration and DO flux have been observed during this study. The oxygen consumption rate at all study sites had a mean of –89 (±44) mmol m –2 d –1 while the oxygen production rate due to benthic algae had a mean of 131 (±103) mmol m –2 d –1. There was a strong correlation (r=0.91) between oxygen consumption rate and temperature. This was presumably because of the temperature influence on rates of microbial and macrobenthic processes. The mean benthic primary production rate at all study sites was 1216 (±957) mg C m –2 d –1 between June 2000 and February 2001. Annual gross benthic primary production was estimated from the gross mean daily benthic DO production (P) and Redfield's C:O 2 ratio of 106:138 to be 420 g C m –2 y –1 at station HO, 250 g C m –2 y –1 at B2 and 340 g C m –2 y –1 at station 95. Thus, the mean gross benthic primary production was estimated as 1151 mg C m –2 d –1 at station HO, 685 mg C m –2 d –1 at station B2, and 932 mg C m –2 d –1 at station 95. 相似文献
9.
Extensive microbial studies of the Arabian Gulf marine environment have led to the discovery of several new species of endolithic cyanobacteria. Those species were taxonomically classified under cyanophyta and belonging to the genes Hyella, Solentia and cyanosacus. In this study Hyella immanis was isolated and cultured under laboratory conditions and used as a model to calculate boring rates for genus Hyella. Boring rates were measured under light intensity of 20-25 ??E m −2 s −1 of 16:8 h LD cycle, 1 h d −1 agitation, and no agitation. Light, Scanning Electron Microscopy (SEM) and embedding techniques were used to provide information on boring rates, boring patterns, and cells morphology. Mean boring rates of seven colonies were found to lie between 166 and 510 ??m 3 d −1 at various growth stages, with a boring rate of 10 ??m d −1 in calcite. Calculated boring rates tend to be accelerated at early stage of colony development and enhanced with agitation. Rates of calcite removal for control and under agitated conditions in early stage (20-50 day) were 150 ??m 3 d −1 and 357 ??m 3 d −1 respectively. However, in late stage (50-70 days) control and agitated conditions removal was 185 ??m 3 d −1 and 173 ??m 3 d −1 respectively. 相似文献
10.
Enhancement of Cr (VI) reduction rate and power production from biocathode microbial fuel cells (MFCs) was achieved using
indigenous bacteria from Cr (VI)-contaminated site as inoculum and MFC architecture with a relatively large cathode-specific
surface area of 340–900 m 2 m −3. A specific Cr (VI) reduction rate of 2.4 ± 0.2 mg g −1VSS h −1 and a power production of 2.4 ± 0.1 W m −3 at a current density of 6.9 A m −3 were simultaneously achieved at an initial Cr (VI) concentration of 39.2 mg L −1. Initial Cr (VI) concentration and solution conductivity affected Cr (VI) reduction rate, power production and coulombic
efficiency. These findings demonstrate the importance of inoculation and MFC architecture in the enhancement of Cr (VI) reduction
rate and power production. This study is a beneficial attempt to improve the efficiency of biocathode MFCs and provide a good
candidate of bioremediation process for Cr (VI)-contaminated sites. 相似文献
11.
Over 1,000t fresh weight of Ulva was cultivated on South African abalone farms in 2007, primarily for feed, but in one case to allow partial re-circulation
by nutrient removal. The potential of this new commercial crop is analysed. Material is collected from natural free-floating
populations and at least four species are commonly grown, with different ecophysiological characteristics. A brown epiphyte,
Myrionema strangulans, causes a disease of the Ulva, which is currently managed by farmers by re-stocking. The main potential threat is that some farmers are wary of integrated
systems, fearing they may promote disease in abalone, although Ulva has been grown in abalone effluent and fed back to the abalone on one farm for 6 years without adverse effects. Opportunities
exist for the expansion of Ulva cultivation via further spread of the abalone industry, the inclusion of seaweed raceways in proposed fish-farming activities,
or the potential for the inclusion of high quality cultivated Ulva as a constituent in aquafeed. A conservative estimate of production over a full year from these raceway systems was 26.1 g
dw m −2 day −1 (2006) and 19.7 g dw m −2 day −1 (2007), similar to maximum figures for total annual microalgal biomass production in outdoor systems. 相似文献
12.
The influence of three different initial stocking densities (SD) in flowthrough systems was evaluated on growth performance and feed utilizaition in beluga, Huso huso, and ship sturgeon, Acipenser nudiventris, juveniles in three different grow‐out phases for 228 days. In each grow‐out phase, fish were randomly distributed in 18 concrete square tanks (2.0 × 1.0 × 1.2 m 3; 2 m 3 of volume) according to the experimental SD. At the first phase, both fish species were subjected to three SD including 1.5, 3 and 6 kg/m 2 for 60 days. In the second phase, fish were submitted to three SD including 3, 6 and 9 kg/m 2, whereas in the third phase, beluga were stocked at 6, 9 and 12 kg/m 2 and ship sturgeon were stocked at 6, 8 and 10 kg/m 2 and each phase lasted for 12 weeks. In both species, the growth performance and feed intake (FI) significantly decreased with increasing SD at the end of the first phase ( p < 0.05). In the second phase, growth performance and FI in beluga decreased with increasing SD, whereas in ship sturgeon neither growth nor FI were affected by SD. Interestingly, the growth performance and feed utilization in both species were not decreased with increasing SD in the third phase indicating adaptability of these species to high stocking density during grow‐out period. According to the result of this study, the appropriate initial SD for beluga within the range of 100–500, 500–2,000 and 1,500–3,000 g were at 1.5, 6 and 12 kg/m 2, respectively in an open flow‐throw system. Regarding to ship sturgeon, initial SD at 1.5 and 10 kg/m 2recommended for fish within the range of 100–300 and 300–1,200 g, respectively in an open flow‐throw system. 相似文献
13.
Geobacter sulfurreducens produces current densities in microbial fuel cells that are among the highest known for pure cultures. The possibility of adapting this organism to produce even higher current densities was evaluated. A system in which a graphite anode was poised at −400 mV (versus Ag/AgCl) was inoculated with the wild-type strain of G. sulfurreducens, strain DL-1. An isolate, designated strain KN400, was recovered from the biofilm after 5 months of growth on the electrode. KN400 was much more effective in current production than strain DL-1. This was apparent with anodes poised at −400 mV, as well as in systems run in true fuel cell mode. KN400 had current (7.6 A/m 2) and power (3.9 W/m 2) densities that respectively were substantially higher than those of DL1 (1.4 A/m 2 and 0.5 W/m 2). On a per cell basis KN400 was more effective in current production than DL1, requiring thinner biofilms to make equivalent current. The enhanced capacity for current production in KN400 was associated with a greater abundance of electrically conductive microbial nanowires than DL1 and lower internal resistance (0.015 versus 0.130 Ω/m 2) and mass transfer limitation in KN400 fuel cells. KN400 produced flagella, whereas DL1 does not. Surprisingly, KN400 had much less outer-surface c-type cytochromes than DL1. KN400 also had a greater propensity to form biofilms on glass or graphite than DL1, even when growing with the soluble electron acceptor, fumarate. These results demonstrate that it is possible to enhance the ability of microorganisms to electrochemically interact with electrodes with the appropriate selective pressure and that improved current production is associated with clear differences in the properties of the outer surface of the cell that may provide insights into the mechanisms for microbe–electrode interactions. 相似文献
14.
Permafrost soils are a significant global store of carbon (C) with the potential to become a large C source to the atmosphere.
Climate change is causing permafrost to thaw, which can affect primary production and decomposition, therefore affecting ecosystem
C balance. To understand future responses of permafrost soils to climate change, we inventoried current soil C stocks, investigated
∆ 14C, C:N, δ 13C, and δ 15N depth profiles, modeled soil C accumulation rates, and calculated decadal net ecosystem production (NEP) in subarctic tundra
soils undergoing minimal, moderate, and extensive permafrost thaw near Eight Mile Lake (EML) in Healy, Alaska. We modeled
decadal and millennial soil C inputs, decomposition constants, and C accumulation rates by plotting cumulative C inventories
against C ages based on radiocarbon dating of surface and deep soils, respectively. Soil C stocks at EML were substantial,
over 50 kg C m −2 in the top meter, and did not differ much among sites. Carbon to nitrogen ratio, δ 13C, and δ 15N depth profiles indicated most of the decomposition occurred within the organic soil horizon and practically ceased in deeper,
frozen horizons. The average C accumulation rate for EML surface soils was 25.8 g C m −2 y −1 and the rate for the deep soil accumulation was 2.3 g C m −2 y −1, indicating these systems have been C sinks throughout the Holocene. Decadal net ecosystem production averaged 14.4 g C m −2 y −1. However, the shape of decadal C accumulation curves, combined with recent annual NEP measurements, indicates soil C accumulation
has halted and the ecosystem may be becoming a C source. Thus, the net impact of climate warming on tundra ecosystem C balance
includes not only becoming a C source but also the loss of C uptake capacity these systems have provided over the past ten
thousand years. 相似文献
15.
In a microbial electrolysis cell (MEC), hydrolysate produced by hydrothermal treatment of wheat straw was used for hydrogen
production during selective recovery of phenols. The average H 2 production rate was 0.61 m 3 H 2/m 3 MEC·day and equivalent to a rate of 0.40 kg COD/m 3 MEC·day. The microbial community in the anode biofilm was adapted by establishment of xylose-degrading bacteria of the Bacteriodetes
phylum (16%) and Geobacter sulfurreducens (49%). During the process, 61% of the chemical oxygen demand was removed as hydrogen at 64% yield. The total energy production
yield was 78% considering the energy content in the consumed compounds and the cell voltage of 0.7 V. The highest hydrogen
production was equivalent to 0.8 kg COD/m 3 MEC·day and was obtained at pH 7–8 and 25°C. Accumulation of 53% w/v phenolic compounds in the liquor was obtained by stepwise
addition of the hydrolysate during simultaneous production of hydrogen from consumption of 95% for the hemicellulose and 100%
of the fatty acids. Final calculations showed that hydrolysate produced from 1 kg wheat straw was upgraded by means of the
MEC to 22 g hydrogen (266 L), 8 g xylan, and 9 g polyphenolics for potential utilization in biobased materials. 相似文献
16.
There is a need to develop low operational intensity, cost-effective, and small-footprint systems to treat wastewater. Partial nitritation has been studied using a variety of control strategies, however, a gap in passive operation is evident. This research investigates the use of elevated loading rates as a strategy for achieving low operational intensity partial nitritation in a moving bed biofilm reactor (MBBR) system. The effects of loading rates on nitrification kinetics and biofilm characteristics were determined at elevated, steady dissolved oxygen concentrations between 5.5 and 7.0 mg O2/L and ambient temperatures between 19 and 21 °C. Four elevated loading rates (3, 4, 5 and 6.5 g NH4+-N/m2 days) were tested with a distinct shift in kinetics being observed towards nitritation at elevated loadings. Complete partial nitritation (100% nitrite production) was achieved at 6.5 g NH4+-N/m2 days, likely due to thick biofilm (572 µm) and elevated NH4+-N load, which resulted in suppression of nitrite oxidation. 相似文献
17.
Microaerobic activated sludge (MAS) is a one-stage process operated at 0.5–1.0 mg l −1 dissolved oxygen (DO) aiming at simultaneous nitrification and denitrification. We used molecular techniques and a comprehensive nitrogen (N)-transformation activity test to investigate the dominant NH 3-oxidizing and N 2-producing mechanism as well as the dominant ammonia-oxidizing bacteria (AOB) species in sludge samples individually collected from an MAS system and a conventional anoxic/oxic (A/O) system; both systems were operated at a normal loading rate (i.e. 1.0 kg chemical oxygen demand (COD) m −3 day −1 and 0.1 kg NH 4+-N m −3 day −1) in our previous studies. The DO levels in both systems (aerobic: conventional A/O system; microaerobic: MAS system) did not affect the dominant NH 3-oxidizing mechanism or the dominant AOB species. This study further demonstrated the feasibility of a higher loading rate (i.e. 2.30 kg COD m −3 day −1 and 0.34 kg NH 4+-N m −3 day −1) with the MAS process during sewage treatment, which achieved a 40% reduction in aeration energy consumption than that obtained in the conventional A/O system. The increase in loading rates in the MAS system did not affect the dominant NH 3-oxidizing mechanism but did impact the dominant AOB species. Besides, N 2 was predominantly produced by microaerobic denitrification in the MAS system at the two loading rates. 相似文献
18.
Methane and carbon dioxide emission from three constructed ponds were monitored during an annual cycle. Water temperature was a good predictor of methane emission in all three ponds. In the most intensively studied pond, nitrate concentration in the bottom water could further explain the amount of methane emitted. When water temperature exceeded 15 °C between 1 and 54 mg, CH 4 m −2 h −1 was emitted on all occasions, while at temperatures below 10 °C, less than 0.6 mg CH 4 m −2 h −1 was emitted. The flux of carbon dioxide differed between the ponds and no consistent patterns were found. In a laboratory study at 20 °C, we showed that high, but naturally occurring, nitrate concentrations (8 and 16 mg NO 3−–N l −1) constrained the production of methane compared to the treatment with no nitrate addition. Nitrous oxide production was positively correlated with nitrate concentration. Carbon dioxide production was highest at the highest nitrate concentration, which indicates that increased nitrate loading on ponds and wetlands will stimulate organic matter decomposition rates. Our conclusion is that these ponds constructed for nitrate removal emit greenhouse gases comparable to lakes in the temperate region. 相似文献
19.
The zooxanthellate octocoral Sinularia flexibilis is a producer of potential pharmaceutically important metabolites such as antimicrobial and cytotoxic substances. Controlled
rearing of the coral, as an alternative for commercial exploitation of these compounds, requires the study of species-specific
growth requirements. In this study, phototrophic vs. heterotrophic daily energy demands of S. flexibilis was investigated through light and Artemia feeding trials in the laboratory. Rate of photosynthetic oxygen by zooxanthellae in light (≈200 μmol quanta m −2 s −1) was measured for the coral colonies with and without feeding on Artemia nauplii. Respiratory oxygen was measured in the dark, again with and without Artemia nauplii. Photosynthesis–irradiance curve at light intensities of 0, 50, 100, 200, and 400 μmol quanta m −2 s −1 showed an increase in photosynthetic oxygen production up to a light intensity between 100 and 200 μmol quanta m −2 s −1. The photosynthesis to respiration ratio (P/R > 1) confirmed phototrophy of S. flexibilis. Both fed and non-fed colonies in the light showed high carbon contribution by zooxanthellae to animal (host) respiration
values of 111–127%. Carbon energy equivalents allocated to the coral growth averaged 6–12% of total photosynthesis energy
(mg C g
−
1 buoyant weight day
−
1) and about 0.02% of the total daily radiant energy. “Light utilization efficiency (ε)” estimated an average ε value of 75%
12 h
−
1 for coral practical energetics. This study shows that besides a fundamental role of phototrophy vs. heterotrophy in daily
energy budget of S. flexibilis, an efficient fraction of irradiance is converted to useable energy. 相似文献
20.
Water and energy are closely connected and both are very important for human development. Wastewater treatment plants (WWTPs) are central to water–energy interactions as they consume energy to remove pollutants and thus reduce the human gray water footprint on the natural water environment. In this work, we quantified energy consumption in 9 different WWTPs in south China, with different treatment processes, objects, and capacities. The energy intensity in most of these WWTPs is in the range of 0.4–0.5 kWh/m 3 in 2014. Footprint methodologies were used in this paper to provide insight into the environmental changes that result from WWTPs. A new indicator “gray water footprint reduction” is proposed based on the notion of gray water footprint to better assess the role of WWTPs in reducing human impacts on water resources. We find that higher capacity and appropriate technology of the WWTPs will result in higher gray water footprint reduction. On average, 6.78 m 3 gray water footprint is reduced when 1 m 3 domestic sewage is treated in WWTPs in China. 13.38 L freshwater are required to produce the 0.4 kWh electrical input needed for treating 1 m 3 domestic wastewater, and 0.23 kg CO 2 is emitted during this process. The wastewater characteristics, treatment technologies as well as management systems have a major impact on the efficiency of energy utilization in reducing gray water footprint via these WWTPs. The additional climate impact associated with wastewater treatment should be considered in China due to the enormous annual wastewater discharge. Policy suggestions are provided based on results in this work and the features of China's energy and water distribution. 相似文献
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