Increase In Organic Matter Concentration Research Articles

Effect of organic concentration on biological activity and nitrogen removal performance in an anammox biofilm system.

The effects of different concentrations of organic matter on the biological activity and nitrogen removal performance of the anaerobic ammonium oxidation (anammox) system was studied. The results showed that under the conditions of low influent total organic carbon (TOC ≤ 100 mg/L), the activity rate of anammox bacteria was basically unaffected, the anammox bacteria and denitrifying bacteria formed a good synergistic effect, and the maximum total nitrogen (TN) removal efficiency reached 95.77%. However, when the influent TOC concentration was up to 200 mg/L, the activity of anammox bacteria was seriously inhibited. At this time, denitrification becomes the main pathway of nitrogen removal, the effluent ammonia nitrogen content increases, and the TN removal efficiency decreases to 64.17%. High-throughput sequencing analysis showed that with the increase in organic matter concentration, the relative abundance of Proteobacteria and Planctomycetes changed significantly. In particular, the relative abundance proportion of Proteobacteria increased from 21.06% to 25.57%, the Planctomycetes dropped from 10.01% to 3.03% and the Candidatus Brocadia genus had the largest decrease. In conclusion, the concentration range of organic matter for collaborative denitrification was proposed in this study, which provided theoretical reference for the practical application of anammox biofilm process.

Parkinson’s disease aggravation in association with fine particle components in New York State

BackgroundLong-term exposure to fine particulate matter (PM2.5) has been associated with neurodegenerative diseases, including disease aggravation in Parkinson's disease (PD), but associations with specific PM2.5 components have not been evaluated. ObjectiveTo characterize the association between specific PM2.5 components and PD first hospitalization, a surrogate for disease aggravation. MethodsWe obtained data on hospitalizations from the New York Department of Health Statewide Planning and Research Cooperative System (2000–2014) to calculate annual first PD hospitalization counts in New York State per county. We used well-validated prediction models at 1 km2 resolution to estimate county level population-weighted annual black carbon (BC), organic matter (OM), nitrate, sulfate, sea salt (SS), and soil particle concentrations. We then used a multi-pollutant mixed quasi-Poisson model with county-specific random intercepts to estimate rate ratios (RR) of one-year exposure to each PM2.5 component and PD disease aggravation. We evaluated potential nonlinear exposure–outcome relationships using penalized splines and accounted for potential confounders. ResultsWe observed a total of 197,545 PD first hospitalizations in NYS from 2000 to 2014. The annual average count per county was 212 first hospitalizations. The RR (95% confidence interval) for PD aggravation was 1.06 (1.03, 1.10) per one standard deviation (SD) increase in nitrate concentrations and 1.06 (1.04, 1.09) for the corresponding increase in OM concentrations. We also found a nonlinear inverse association between PD aggravation and BC at concentrations above the 96th percentile. We found a marginal association with SS and no association with sulfate or soil exposure. ConclusionIn this study, we detected associations between the PM2.5 components OM and nitrate with PD disease aggravation. Our findings support that PM2.5 adverse effects on PD may vary by particle composition.

Juvenile Oyster (Crassostrea virginica) Biodeposits Contribute to a Rapid Rise in Sediment Nutrients on Restored Intertidal Oyster Reefs (Mosquito Lagoon, FL, USA)

By filtering large volumes of water and releasing nutrient-rich biodeposits (feces and pseudofeces), oysters can locally enhance sediment biogeochemical cycling. An active Crassostrea virginica restoration program in Mosquito Lagoon, FL (USA), was leveraged to assess the immediate (first-year) effects of restoration on sediment nutrients. Measurements included extractable and total carbon, nitrogen, and phosphorus on dead, natural, and restored reefs using a before-after-control-impact design. To investigate an observed “age-nutrient paradox” in sediment nutrient concentrations, a laboratory experiment compared feeding rates and biodeposit nutrient content between juvenile and older oysters. The field study documented a 136% increase in ammonium, 78% increase in total nitrogen, 46% increase in total phosphorus, and 75% increase in organic matter concentrations 12 months post-restoration, with extractable nutrients responding more rapidly to restoration than total nutrients. Sediment nutrient increases were positively correlated with oyster density, shell length, and reef height. Moreover, the laboratory study indicated juvenile oysters had higher rates of chlorophyll-a removal and ammonium efflux and produced biodeposits with higher concentrations of dissolved organic carbon, nitrate, and ammonium than older oysters. Overall, this study documented increases in sediment nutrients on intertidal reefs within the first year of restoration, which may be explained by a greater filtration rate and more nutrient-enriched biodeposits contributed by young oysters as compared to older oysters. Sediment total nitrogen and ammonium content may be the most robust monitoring metrics for documenting the ecosystem service of enhanced biogeochemical cycling on restored oyster reefs.

Influence of stormwater infiltration systems on the structure and the activities of groundwater biofilms: Are the effects restricted to rainy periods?

Stormwater infiltration systems (SIS) have been set up to collect and infiltrate urban stormwater runoff in order to reduce flooding and to artificially recharge aquifers. Such practices produce environmental changes in shallow groundwater ecosystems like an increase in organic matter concentrations that could drive changes in structure and functions of groundwater microbial communities. Previous works suggested that SIS influence groundwater physico-chemistry during either rainy and dry period but no study has examined the impact of SIS on groundwater microorganisms during both periods. This study aimed to fill this gap by assessing SIS impacts on groundwater quality parameters in three SIS with vadose zone thickness < 3 m during two contrasting meteorological conditions (rainy/dry periods). Physicochemical (dissolved organic carbon and nutrient concentrations) and microbial variables (biomass, dehydrogenase and hydrolytic activities, and bacterial community structure) were assessed on SIS-impacted and non-SIS-impacted zones of the aquifers for the three SIS. Using clay beads incubated in the aquifer to collect microbial biofilm, we show that SIS increased microbial activities, bacterial richness and diversity in groundwater biofilms during the rainy period but not during the dry period. In contrast, the significant differences in dissolved organic carbon and nutrient concentrations, biofilm biomass and bacterial community structures (Bray-Curtis distances, relative abundances of main bacterial orders) measured between SIS-impacted and non-SIS-impacted zones of the aquifer were comparable during the two periods. These results suggest that structural indicators of biofilm like biomass were probably controlled by long-term effects of SIS on concentrations of dissolved organic matter and nutrients whereas biofilm activities and bacterial richness were temporally stimulated by stormwater runoff infiltrations during the rainy period. This decoupling between the structural and functional responses of groundwater biofilms to stormwater infiltration practices suggests that biofilms functions were highly reactive to fluxes associated with aquifer recharge events.

Stability and purification efficiency of composite ecological floating bed with suspended inorganic functional filler in a field study

Planting macrophytes can increase the contribution of plant uptake to pollutant removal in ecological floating bed (EFB). However, the low system stability of traditional EFB often causes large-area plant lodging during the rainy season. This phenomenon not only reduces the ornamental value of EFB but also causes the problem of secondary pollution. Furthermore, the reduction of removal rate under low temperature condition is also an inevitable defect in the application of EFB. Therefore, a composite EFB (CEFB) was built by suspending inorganic functional filler below the traditional EFB to remedy these defects. Results of a two-year field test showed that the suspension of inorganic functional filler not only enhanced the system stability, plant lodging resistance and removal efficiency of CEFB but also fundamentally resolved the problem of low purification efficiency of the traditional EFB during the low-temperature season. Compared with EFB, CEFB could increase the average removal rates of total nitrogen (TN), ammonia nitrogen (NH4+-N), total phosphorus (TP), phosphate (PO43−-P), turbidity, algae density and chlorophyll-a (Chl-a) by 46.85 %, 53.97 %, 44.45 %, 54.55 %, 53.63 %, 42.16 % and 29.79 %, respectively. In addition, CEFB effectively avoided the great increase in organic matter concentration and the decline in sensory effects of the scenic water caused by plant lodging and plant tissue decomposition. In general, the suspension of inorganic functional filler could enhance the plant lodging resistance and purification efficiency of CEFB evidently, which is expected to become a feasible approach for eutrophic water restoration.

Investigations of primary and secondary particulate matter of different wood combustion appliances with a high-resolution time-of-flight aerosol mass spectrometer

Abstract. A series of photo-oxidation smog chamber experiments were performed to investigate the primary emissions and secondary aerosol formation from two different log wood burners and a residential pellet burner under different burning conditions: starting and flaming phase. Emissions were sampled from the chimney and injected into the smog chamber leading to primary organic aerosol (POA) concentrations comparable to ambient levels. The composition of the aerosol was measured by an Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS) and black carbon (BC) instrumentation. The primary emissions were then exposed to xenon light to initiate photo-chemistry and subsequent secondary organic aerosol (SOA) production. After correcting for wall losses, the average increase in organic matter (OM) concentrations by SOA formation for the starting and flaming phase experiments with the two log wood burners was found to be a factor of 4.1±1.4 after five hours of aging. No SOA formation was observed for the stable burning phase of the pellet burner. The startup emissions of the pellet burner showed an increase in OM concentration by a factor of 3.3. Including the measured SOA formation potential, average emission factors of BC+POA+SOA, calculated from CO2 emission, were found to be in the range of 0.04 to 3.9 g/kg wood for the stable burning pellet burner and an old log wood burner during startup respectively. SOA contributed significantly to the ion C2H4O2+ at mass to charge ratio m/z 60, a commonly used marker for primary emissions of wood burning. This contribution at m/z 60 can overcompensate for the degradation of levoglucosan leading to an overestimation of the contribution of wood burning or biomass burning to the total OM. The primary organic emissions from the three different burners showed a wide range in O:C atomic ratio (0.19−0.60) for the starting and flaming conditions, which also increased during aging. Primary wood burning emissions have a rather low relative contribution at m/z 43 (f 43) to the total organic mass spectrum. The non-oxidized fragment C3H7+ has a considerable contribution at m/z 43 for the fresh OA with an increasing contribution of the oxygenated ion C2H3O+ during aging. After five hours of aging, the OA has a rather low C2H3O+ signal for a given CO2+ fraction, possibly indicating a higher ratio of acid to non-acid oxygenated compounds in wood burning OA compared to other oxygenated organic aerosol (OOA).

Application of sugar foam to red soils in a semiarid Mediterranean environment

The study described here involved evaluating the effects that the application of one by-product (sugar foam waste) has upon red soils in the region of La Mancha (Central Spain). In view of the fact that this is a location where this type of soil abounds, this technique has been a common practice for many years. The principal goal was to investigate the impact of this approach on some of the soil properties and, secondly, on its level of fertility. As a result, this represents an investigation into the effects that this type of waste has on some soil quality parameters. The results showed that, after the addition of by-products over 25 years, sugar foam waste is of agricultural interest mainly due to the increase in organic matter concentration (about 2%) and, to a lesser extent, by increases in calcium carbonate (more than 30%) and P (four times more). The soil pH was also found to increase slightly (1.4), while the electrical conductivity almost did not change. The properties associated with these pedological qualities therefore had a positive effect by improving nutrient availability. As a result, foams arising from sugar industries have a positive effect on soil quality and the application of such foams to soils is beneficial since the need to dispose this residue is also removed.

Imidazolium based ionic liquids in soils: effects of the side chain length on wheat (Triticum aestivum) and cress (Lepidium sativum) as affected by different clays and organic matter

This study provides data on the behaviour and toxicity of selected imidazolium based ionic liquids in the terrestrial environment with the aim to contribute to a prospective hazard assessment. Using the plant growth inhibition assay with wheat (Triticum aestivum) and cress (Lepidium sativum) we investigated the influence of two different clay minerals (kaolinite and smectite) in varying concentrations and clay mineral mixtures as well as the influence of organic matter in varying concentrations on the toxicity of three imidazolium based ionic liquids differing in the alkyl side chain length. The obtained results were compared to the German standard soil Lufa 2.2. Overall the influence of the 2:1 layer mineral smectite on toxicity was stronger than for the 1:1 layer mineral kaolinite resulting in lower toxicities when smectite was present. Comparable results were achieved in the tests with different clay mineral mixtures. The influence of the clay minerals was substance concentration dependent and the side chain effect could not consistently be confirmed for the different soil mixtures. The 1:1 clay mineral kaolinite caused in some cases an increase in toxicity. The obtained results for the influence of organic matter on the toxicity proved to be much more consistent than for the clay minerals: here an increase in organic matter concentration always resulted in a decrease of the toxicity. Differences in plant species sensitivity could be shown, but not in a consistent manner. A site specific hazard assessment of ionic liquids should therefore take into account organic matter content, quantity and especially quality of clay minerals.

Study of the effect of pH, salinity and DOC on fluorescence of synthetic mixtures of freshwater and marine salts.

In order to provide support for the discussion of the fate of organic matter in estuaries, a laboratory simulation was performed by changing freshwater ionic strength, pH and organic matter content. The change in spectroscopic characteristics caused by variations in salinity, pH and organic matter concentration in the filtered samples was observed by UV-Vis and fluorescence spectroscopy. The increase in emission fluorescence intensity of dissolved organic matter (DOM) due to increasing salinity (in the range 0 to 5 g l-1) is affected by the pH of the samples. The emission fluorescence intensity at the three maxima observed in the fluorescence spectra, is linearly correlated with dissolved organic carbon (DOC) concentration at several salinity values in the same sample. The increase in organic matter concentration caused a shift in the emission peak wavelength at 410 nm for several salinity values. We concluded that it is necessary to take into account the influence of salinity and pH on emission fluorescence of dissolved organic matter if it is to be used as a tracer in estuarine or near shore areas.

Factors limiting the intake of feed by sheep. 15. Voluntary feed consumption and digestion in lambs fed chopped roughage diets varying in quality

Feed intake and digestion transactions for diets based on wheaten straw and mature ryegrass diets, both supplemented to provide additional essential nutrients, were compared with those for lucerne hay and high quality forage oats diets in lambs weighing c. 24 kg. The data obtained and comparable published data were used to examine relationships between a range of variables. Decrease in roughage quality, as evidenced by decrease in digestible organic matter (OM) intake, was accompanied by increase in (i) times spent eating, ruminating and chewing rumination boluses, (ii) the quantities of digesta or digesta OM in the reticula-rumen and omasum. It was not associated with increase in the large particle content of rumen or omasum digesta. Over the range of diets, close direct relations were demonstrated between (i) ruminating time and the amount of digesta in the reticulo-rumen, (ii) the amounts of digesta in the reticulo-rumen and omasum, (iii) the OM concentrations in rumen and reticulum digesta, (iv) the OM concentrations in reticulum and omasum digesta, (v) the OM concentration of reticulum digesta and of digesta flowing to the omasum, and (vi) the increase in OM concentration from reticulum to omasum digesta and OM concentration of reticulum digesta. Reticulum digesta were of finer texture than rumen digesta, and the bulk density of digesta particle fractions varied between diets, and sometimes between rumen and large intestine digesta. With a straw-based diet, relative to lucerne hay, small particles ( &lt;600 �m sieve) were cleared more slowly from the reticula-rumen, associated with a larger reticulo-rumen particle pool. The data are discussed in relation to (i) the flow of digesta through the alimentary tract and (ii) the regulation of roughage intake. They were considered to be consistent with a concept that energy metabolism and digesta load in the reticulo-rumen interact in the regulation of roughage intake.

Nitrogen and organic-matter accumulation in coal mine spoils supporting red alder stands

Rates of nitrogen and organic-matter accumulation under red alder (Alnusrubra Bong.) stands were estimated by analyzing spoil materials at three abandoned open-pit coal-mine areas in western Washington. Average age of trees in natural stands at the three study areas varied from 10 to 30 years. Mean site indices (50 years) varied from 27 to 30 m. Mean pH of spoil surface samples varied from 4.0 to 4.6 which was less than for adjacent alder stands on natural soils but similar to values reported for alder stands in western Oregon. The increase in organic matter concentration in the surface 18 cm ranged from 0.96% under the 10-year-old stand to 2.94% under the 30-year-old stand. This represented an average increase of about 0.09% per year for all three stands with no significant differences among stands. The mean increase in nitrogen concentration ranged from 0.04 to 0.14% for the 10- and 30-year-old stands, respectively. This corresponded to an annual increase of 0.004% N with no significant difference among areas. Average rate of N accumulation in spoils varied from 59 to 65 kg N/ha•year−1. Differences between areas were not significant.