PO4 Concentrations Research Articles

Prawn larvae of Macrobrachium amazonicum (Decapoda, Palaemonidae) in contaminated oligohaline creeks on the Amazon estuary

ABSTRACTThe objective of this study was to assess larval stage densities of Macrobrachium amazonicum in two highly contaminated amazonian creeks (Tucunduba and Mata Fome) and in one creek less impacted by human activities (Combu). The hypothesis tested is that larvae are more abundant in protected areas, independently of their development stage. Zooplankton was collected once every 3 months by conducting horizontal hauls at the sub-surface of the water column using a 300 µm mesh size plankton net during flood and ebb tides. Temperature, pH, conductivity, salinity, dissolved oxygen, water hardness, biochemical oxygen demand, chemical oxygen demand, Cl, N-NO, NO, NH3, NH4, PO4, SO4, Fe, Mg, Li, K and Na values or concentrations were estimated for each creek in order to determine whether these factors influence larval stage densities. Zoea stages I, V, VIII, X and XI were recorded: zoea stage I was present all along Combu creek and downstream of Tucunduba and Mata Fome creeks; the other stages were encountered only in the uncontaminated creek. Larval stage zoea XI was considered ‘occasional’. Densities were statistically different between months. It was concluded that spawning ground of M. amazonicum was close to the three creeks because the first larval stage was found indiscriminately at all downstream sampling stations. The more advanced stages (zoea V or higher) were found mid-downstream but only in the most preserved creek (Combu); no other larval stage beside zoea I was encountered in the creeks with greater anthropic influence. Further, not only is the adult population affected by water contamination, but also the occurrence of larval stages is associated with more protected waters. The high concentration of coliforms was associated with nitrates, and the low larval density of the Amazonian prawn was a clear response to this contamination of the water.

POTENTIAL ENVIRONMENTAL IMPACTS OF TUNA CAGE FARMING IN THE AEGEAN SEA

The present study aimed to investigate the potential impacts of Atlantic Bluefin Tuna ( Thunnus thynnus ) farming in offshore cage systems in the Aegean Sea (Sigacik Bay-Izmir, Turkey), in respect to physico-chemical water quality parameters, nutrient loads, chlorophyll- a , total suspended solids, zooplankton groups, and TRIX index calculations for the potentially affected cage farm area and an unaffected reference site. Concentrations of physico-chemical variables (temperature, salinity, dissolved oxygen, pH) in the study carried out in May and August 2018, were within the acceptable limits for marine aquaculture in terms of water quality characteristics. The concentrations of PO 4 -P, NH 4 -N, and NO 2 -N showed no temporal or spatial changes, and were recorded below 0.01 mg/L (<0.01) for PO 4 -P and NH 4 -N, whereas lower than 0.005 mg/L (<0.005) for NO 2 -N values in both cage and reference stations in May and August 2018 periods. Results showed low levels of TSS (0.33-11.87 mg/L), both in the cage farm area and the reference site, remaining below the general quality criteria of 30 mg/L for marine environment. No eutrophication risk (TRIX index, T<4 ) was observed around the Tuna Cage Farm Site in Sigacik Bay, according to the legislations enacted for “Sensitive Areas of Enclosed Bays where fish farms are not allowed”. Based on these findings, demonstrating highly interactive trophic level variability, it can be concluded that the impacts of the Tuna Cage Farm were not significant, possibly due to the consistent movement of the water in currents in the study area.

Investigation on the control of phosphate leaching by sorption and colloidal transport: Column studies and multi-surface complexation modelling

Surface complexation modelling (SCM) is a powerful tool to estimate speciation and fate of solutes in soil, provided sufficient model validation. This study aims to describe phosphate (PO4) leaching with SCM. The leachate phosphorus concentrations ([P]) of 120 unsaturated columns of contrasting agricultural soils were measured and modelled. Leachate [P] ranged 0.7–240 μM. Leachate [P] increased as the ratio of P to iron and aluminium (PAl+Fe) in acid oxalate soil extracts increased and as leachate Fe and Al concentrations ([Al + Fe]) increased. SCM was used to describe PO4 sorption to ferrihydrite (CD-MUSIC model). This yielded adequate description of leachate [P] (RMSElog10 = 0.39), but only when reactive PO4 was described from isotopically exchangeable PO4, when organic matter was included as the main competing adsorbate and when mobile colloidal ferrihydrite was included. The model reveals that colloidal PO4 transport enhanced leachate PO4 concentrations up to a factor 50 at small soil P content and small calcium (Ca2+) concentration in solution, as a large Ca2+ concentration enhances colloidal stability. This modelling approach explained that long-term application of organic fertilisers with higher Ca content reduced P leaching, likely due to the effect of Ca2+ on colloidal stability. A two-parameter empirical Langmuir model, based on soil Fe and Al oxyhydroxides, fitted data better than any SCM, suggesting that the empirical model might be advocated for application at large scale. This study revealed the power of SCM to better understand colloidal transport of P in soil.

Responses of stream water quality concentrations to vegetative cover variation in Muar River watershed

ABSTRACTAnalysis of the historical land-cover of Muar River watershed has shown that forest and agriculture are the dominant land-covers over the last three decades. This information was used to evaluate the relationship between the vegetative landscape variation to stream water quality concentrations which was to provide an insight for management of water quality under humid tropical climate. Three out of the six water quality variables simulated using the hydrological simulation program FORTRAN (HSPF) model are sensitive to change in vegetative land-covers which include; biochemical oxygen demand (BOD), nitrate-nitrogen (NO3-N), and orthophosphate (PO4) concentrations. However, total suspended solids (TSS), dissolved oxygen (DO), and ammonia-nitrogen (NH3-N) concentrations remain insensitive. Further analysis shows that patch density (PD) has a little impact on BOD, NO3-N, and PO4 concentrations compared to edge density (ED), largest patch index (LPI), and landscape shape index (LSI) under varied landscape conditions. However, large ED, LPI, and LSI indices in both forest and agriculture will result to increase in BOD, NO3-N, and PO4 concentrations. Therefore, adequate knowledge of the responses of the water quality concentrations to landscape pattern and its dynamics can serve as an alternative solution to stream water quality deterioration in an abundant rainfall region.

Carbonate Adsorption to Ferrihydrite: Competitive Interaction with Phosphate for Use in Soil Systems.

Carbonate (CO3) interacts with Fe-(hydr)oxide nanoparticles, affecting the availability and geochemical cycle of other important oxyanions in nature. Here, we studied the carbonate–phosphate interaction in closed systems with freshly prepared ferrihydrite (Fh), using batch experiments that cover a wide range of pH values, ionic strength, and CO3 and PO4 concentrations. The surface speciation of CO3 has been assessed by interpreting the ion competition with the Charge Distribution (CD) model, using CD coefficients derived from MO/DTF optimized geometries. Adsorption of CO3 occurs predominately via formation of bidentate inner-sphere complexes, either (≡FeO)2CO or (≡FeO)2CO··Na+. The latter complex is electrostatically promoted at high pH and in the presence of adsorbed PO4. Additionally, a minor complex is present at high CO3 loadings. The CD model, solely parametrized by measuring the pH-dependent PO4 adsorption as a function of the CO3 concentration, successfully predicts the CO3 adsorption to Fh in single-ion systems. The adsorption affinity of CO3 to Fh is higher than to goethite, particularly at high pH and CO3 loadings due to the enhanced formation (≡FeO)2CO··Na+. The PO4 adsorption isotherm in 0.5 M NaHCO3 can be well described, being relevant for assessing the reactive surface area of the natural oxide fraction with soil extractions and CD modeling. Additionally, we have evaluated the enhanced Fh solubility due to Fe(III)-CO3 complex formation and resolved a new species (Fe(CO3)2(OH)23−(aq)), which is dominant in closed systems at high pH. The measured solubility of our Fh agrees with the size-dependent solubility predicted using the surface Gibbs free energy of Fh.

Solid-state speciation of interlayer anions in layered double hydroxides

Layered double hydroxides (LDH) have been proposed for phosphate (PO4) recovery and recycling from waste streams due to their high anion exchange capacity, good stability and high affinity towards PO4. The high affinity towards PO4 strongly relates to the electrostatic interaction with PO4, and thus the charge of PO4. However, the anion speciation of intercalated PO4, i.e. either H2PO4−, HPO42− or PO43− is often overlooked. This study was set up to measure solid phase PO4 speciation through ion exchange stoichiometry, X-ray diffraction (XRD), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and modelling. Six phase pure Mg/Al LDH materials were synthesized using co-precipitation of metal nitrate (NO3−) solutions with varying M2+/M3+ ratio at pH 12 and pH 10. The LDHs synthetized at pH 12 contained larger equivalent fractions of intercalated OH−, smaller fractions of NO3− and smaller interlayer distance than those prepared at pH 10, likely because of the higher OH− concentration in the more alkaline synthesis solutions. Two high charge LDHs prepared at pH 12 or 10 were selected, exchanged with PO4 (0–20 mM initial PO4, 24 h) at one starting pH (7.20); desorption was subsequently performed with carbonate (3 mM, initial pH 8.4) during 480 h. The resulting solution concentrations of NO3, PO4 and CO3 and the pH allowed the identification of the anion exchange stoichiometry. The LDH synthesized at pH 12, which had a large fraction of exchangeable OH−, adsorbed PO4 as HPO42−/PO43−, in exchange for both NO3− and OH− anions. The material synthesized at pH 10 containing a lower fraction of exchangeable OH−, therefore, adsorbed mainly HPO42− in exchange for NO3− anions. The carbonate exchange was consistent with adsorption of divalent CO32−. The pH dependent speciation modelling showed that the exchanged PO4 ions have higher charge compared to those in the contacting solution. This study suggests that the highest P content of LDH is obtained in high charge materials holding divalent PO4 anions, i.e. materials synthesized at lower pH and/or exchanged in solutions with low alkalinity.

Hydrochemistry and hydrodynamics of a Mexican Caribbean Lagoon: Nichupté Lagoon System

The study results describe the hydrogeochemical and the hydrodynamic characterization, and the evolution compounds in the water in the Nichupté Lagoon System (NLS). This is the most representative lagoon of Quintana Roo State and hosts the Natural Protected Area “Manglares de Nichupté” and borders the Punta Cancún-Punta Nizuc National Park. Sampling was performed during rainy and cold-front seasons to asses the distribution and variability of temperature, pH, dissolved axygen salinity, nutrients and major elements. Significant differences were detected for temperature and salinity but not for dissolved oxygen between the seasons. The dissolved oxygen values have considerably diminished in a decade. NOx and PO4 concentrations were high, and did not show significant differences between seasons. NH4+ concentration was an order of magnitude higher in the rainy season. Two types of water occur in the study area (Cl) and (Cl-SO4-Na-Ca-Mg). A strong predominance of Na-Cl, classifies the lagoon system as a brackish lake. Evaporation was the dominant process and the lagoon behaves like a salty lake, with an evolution in the chemical composition of the water, which became enriched in calcium during the cold-front season, and in sulfates during the rainy season. No precipitation of calcite or gypsum was identified, but this could occur during the cold fronts due to the geochemical evolution observed in the Spencer diagram. Nutrient concentrations have increased in ten years, but some are still below Mexican water quality criteria (CE-CCA-001/89). Some sites present high nutrients concentrations like Bojorquez lagoon sites. The results obtained underline: a) high temperature records vis-à-vis of previous studies measurements (historical records), b) decreasing dissolved oxygen concentrations, c) increasing NO3− and PO43− concentrations. These factors combination shows eutrophication signs that should already be taken as an alert. The circulation of the water in the two analyzed periods was qualitatively similar but the magnitudes of the currents were remarkably different between each other. The rainy season (August 2015) showed near-coastal mean currents of magnitude ∼2–3 cm s−1, while the cold-front season (March 2016) showed mean currents about twice stronger (∼5–6 cm s−1). The circulation pattern result in relatively short residence times of the water bodies of the Lagoon System, with values from 3 to 6 weeks in the rainy season; these values can be decreased by 30–50% in the cold-front season.

Point sources and agricultural practices control spatial-temporal patterns of orthophosphate in tributaries to Chesapeake Bay

Orthophosphate (PO4) is the most bioavailable form of phosphorus (P). Excess PO4 may cause harmful algal blooms in aquatic ecosystems. A major restoration effort is underway for Chesapeake Bay (CB) to reduce P, nitrogen, and sediment loading to CB. Although PO4 cycling and delivery to streams has been characterized in small-scale studies, regional drivers of PO4 patterns remain poorly understood because most water quality trend assessment focus on total P. Moreover, these trend assessments are usually at an annual timestep. To address this research gap, we analyzed PO4 patterns over a 9-year period at 53 monitoring stations across the CB watershed to: 1) characterize the role of PO4 in total P fluxes and trends; 2) describe spatial and temporal patterns of PO4 concentrations across seasons and streamflow; and 3) explore factors explaining these patterns. Agricultural watersheds exported the most total P compared with watersheds under different land uses (e.g., urban or forest), with PO4 comprising up to 50% of those exports. Although PO4 exports are declining at many sites, some agricultural regions are experiencing increasing trends at a rate sufficient to drive total P trends. Regression modeling results suggest that point source load reductions are likely responsible for decreasing PO4 concentrations observed at many sites. Watersheds with more Conservation Reserve Program enrollment had lower summer PO4 concentrations, highlighting the effectiveness of this practice. Manure inputs strongly predicted PO4 concentrations at high flows across all seasons. Both manure applications and conservation tillage were correlated with changes in PO4 concentrations at high flow, suggesting these activities could contribute to increasing PO4 concentrations. This study highlights the effectiveness of point source control for reducing PO4 exports and underscores the need for management strategies to target sources, practices, and landscape factors determining PO4 loss from soils where manure inputs remain high.

Efficient phosphate accumulation in the newly isolated Acinetobacter junii strain LH4.

Phosphate (PO43-) accumulation associated with bacteria contributes to efficient remediation of eutrophic waters and has attracted attention due to its low cost, high removal efficiency and environmental friendliness. In the present study, we isolated six strains from sludge with high concentrations of chemical oxygen demand, total nitrogen and total phosphorus levels. Among them, strain LH4 exhibited the greatest PO43- removal ability. Strain LH4 is typical of Acinetobacter junii based on physiological, biochemical, and molecular analyses and is a PO43--accumulating organism (PAO) based on toluidine blue staining. The strain grew quickly when subjected to aerobic medium after pre-incubation under anaerobic condition, with a maximum OD600 of 1.429 after 8h and PO43- removal efficiency of 99%. Our data also indicated that this strain preferred utilizing the carbon(C) sources sodium formate and sodium acetate and the nitrogen(N) sources NH4Cl and (NH4)2SO4 over other compounds. To achieve optimal PO43- removal efficiency, a C:N ratio of 5:1, inoculation concentration of 3%, solution pH of 6, incubation temperature of 30°C, and shaking speed of 100rpm were recommended for A. junii strain LH4. By incubating this strain with different concentrations of PO43-, we calculated that its relative PO43- removal capacity ranged from 0.67 to 3.84mgL-1h-1, ranking in the top three among reported PAOs. Our study provided a new PO43--accumulating bacterial strain that holds promise for remediating eutrophic waters, and its potential for large-scale use warrants further investigation.

Bone metabolic responses to low energy availability achieved by diet or exercise in active eumenorrheic women.

We aimed to explore the effects of low energy availability (EA)[15 kcal·kg lean body mass (LBM)-1·d-1] achieved by diet or exercise on bone turnover markers in active, eumenorrheic women. By using a crossover design, ten eumenorrheic women (VO2 peak: 48.1 ± 3.3 ml·kg-1·min-1) completed all three, 3-day conditions in a randomised order: controlled EA (CON; 45 kcal·kgLBM-1·d-1), low EA through dietary energy restriction (D-RES; 15 kcal·kgLBM-1·d-1) and low EA through increasing exercise energy expenditure (E-RES; 15 kcal·kgLBM-1·d-1), during the follicular phase of three menstrual cycles. In CON, D-RES and E-RES, participants consumed diets providing 45, 15 and 45 kcal·kgLBM-1·d-1. In E-RES only, participants completed supervised running sessions (129 ± 10 min·d-1) at 70% of their VO2 peak that resulted in an exercise energy expenditure of 30 kcal·kg LBM-1·d-1. Blood samples were collected at baseline (BASE) and at the end of the 3-day period (D6) and analysed for bone turnover markers (β-CTX and P1NP), markers of calcium metabolism (PTH, albumin-adjusted Ca, Mg and PO4) and hormones (IGF-1, T3, insulin, leptin and 17β-oestradiol). In D-RES, P1NP concentrations at D6 decreased by 17% (BASE: 54.8 ± 12.7 μg·L-1, D6: 45.2 ± 9.3 μg·L-1, P < 0.001, d = 0.91) and were lower than D6 concentrations in CON (D6: 52.5 ± 11.9 μg·L-1, P = 0.001). P1NP did not change significantly in E-RES (BASE: 55.3 ± 14.4 μg·L-1, D6: 50.9 ± 15.8 μg·L-1, P = 0.14). β-CTX concentrations did not change following D-RES (BASE: 0.48 ± 0.18 μg·L-1, D6: 0.55 ± 0.17 μg·L-1) or E-RES (BASE: 0.47 ± 0.24 μg·L-1, D6: 0.49 ± 0.18 μg·L-1) (condition × time interaction effect, P = 0.17). There were no significant differences in P1NP (P = 0.25) or β-CTX (P = 0.13) responses between D-RES and E-RES. Both conditions resulted in reductions in IGF-1 (-13% and - 23% from BASE in D-RES and E-RES, both P < 0.01) and leptin (-59% and - 61% from BASE in D-RES and E-RES, both P < 0.001); T3 decreased in D-RES only (-15% from BASE, P = 0.002) and PO4 concentrations decreased in E-RES only (-9%, P = 0.03). Low EA achieved through dietary energy restriction resulted in a significant decrease in bone formation but no change in bone resorption, whereas low EA achieved through exercise energy expenditure did not significantly influence bone metabolism. Both low EA conditions elicited significant and similar changes in hormone concentrations.

Quality of leachate from the Oti Landfill Site and its effects on groundwater: a case history

Groundwater quality is an important factor used to determine the suitability of water for drinking, agricultural and domestic purposes. In this study, the effect of leachate from an open landfill site at the Oti community, Kumasi, Ghana, on the groundwater was investigated. A total of 42 water samples, 12 untreated leachate samples, and 6 treated leachate samples were analyzed for physicochemical and bacteriological parameters according to the Standard Methods for the Examination of Water and Wastewater. A comparison of leachate quality with respect to standard limits for wastewater shows that the concentrations of TDS, color, COD, BOD, turbidity, NH3–N, and PO43− were above the desirable limits. The concentrations of PO43− and NH3–N were found to be at considerable levels in the groundwater samples particularly closer to the waste disposal site and relatively reduced values away from the treatment site. The presence of bacteriological indicators in the groundwater samples indicates contamination from leachate sources. The multivariate analysis showed anthropogenic contaminants caused by leachates runoff and the use of chemical fertilizers. The Pearson correlation results showed a significant variation of TDS, NO3–N, SO42−, EC, turbidity, and COD, indicating that high mobility of ions relies on the anthropogenic activities and mineral solubility. The water quality index showed more than 85% of the water samples have poor quality. Insight from this study may be useful to enhance the understanding of the distribution of physicochemical parameters in groundwater, as well as the management and uses of groundwater resources in the Oti community.

The dissolution of phosphorus from Jamaican bauxites under low temperature Bayer conditions

Jamaica has about 7.1% of world bauxite reserves however the ore characteristics vary significantly depending on mining location and mineralogy. Traditionally, low phosphorus hematite-rich deposits from south central Jamaica are processed in a low temperature alumina refinery but these ores are becoming depleted and will be replaced by high phosphorus goethite-rich resources that are located north of the current mines. Depending on type, P-minerals may dissolve during bauxite digestion, accumulate in the liquor and negatively impact the process. This work compares the caustic extractable PO43− from the traditional and future bauxite mining areas and seeks to develop a model to predict soluble PO43− concentrations from their total phosphorus levels measured via XRF. Filtered liquors from the low temperature caustic digestion of 104 samples from a goethite-rich future-bauxite reserve (0.4–32.8% PO43−) and 30 hematite-rich samples (0.1–1.27% PO43−) from current mines were analyzed for soluble PO43− concentrations using the ascorbic acid molybdenum blue spectrophotometric procedure. The concentrations of PO43− in liquor increased dramatically with processing of the goethite-rich ores (5–21,000 mg PO43−/L) in comparison to digestion of the traditional hematite-rich bauxites (52–319 mg PO43−/L if one unusual sample is excluded). An empirical equation (mg PO43−/L = 0.085(mg PO4/kg) + 103; R2 = 0.93) is proposed that uses the total phosphate concentrations of goethite-rich bauxites to predict the soluble PO43− concentrations of their digestion liquors to within ±20% of the measured values. A comparable equation (mg PO43−/L = 0.082 mg PO43−/kg – 26; R2 = 0.67) to predict caustic soluble phosphorus from the hematite-rich ores was also developed however it has a larger margin of error. The correlations are applicable only to normal bauxite samples from the specific mining areas and with Ca:PO43− ratios of <0.40; they are less effective at higher ratios however as apatite or calcite is often present in such bauxites and results in lower than usual soluble PO43− concentrations. Evaluation of the Ca:PO43− ratios in the bauxites in conjunction with the measured soluble PO43− concentrations confirms that crandallite is the dominant P mineral in both the hematite-rich and goethite-rich bauxites.

Distribution Characteristics and Fluxes of Nitrogen and Phosphorus at the Sediment-water Interface of Yuqiao Reservoir

Yuqiao Reservoir is an important source of drinking water in Tianjin. In recent years, the eutrophication status is becoming more and more serious, but its internal loading and distribution characteristics of nitrogen and phosphorus is not clear. The profiles of nitrogen and phosphorus at the sediment-water interface were analyzed using the Peeper (pore water equilibrium) technique and the spatial distribution was investigated. The existing forms of the released nitrogen and phosphorus were investigated by the static intact sediment cores, and the fluxes of nitrogen and phosphorus at the sediment-water interface were estimated by static incubations with intact sediment cores. The results demonstrated the following. ① The contents of PO43--P, NH4+-N, NO3--N, and NO2--N in sediments were 0.5-6.5, 0.5-10.9, 2.2-16.2, and 0.05-0.6 mg ·kg-1, respectively. The contents of nutrient were lower as depth increased, and horizontal distribution characteristics indicated significant differences. ② The contents of PO43--P and NH4+-N in the interstitial water were much higher than in the overlying water, suggesting that the interstitial water had the potential to diffuse nutrients to the overlying water. The concentrations of PO43--P and NH4+-N in the interstitial water increased rapidly at 0-5 cm and then decreased gradually. ③ PO43--P and NH4+-N diffused from the sediment to the overlying water, and the fluxes of them were 1.1-13.3 mg ·(m2 ·d)-1 and 20.6-250.5 mg ·(m2 ·d)-1, respectively. The exchange fluxes of NO3--N and NO2--N ranged from -20.4 to 33.4 mg ·(m2 ·d)-1 and from -7.4 to 0.4 mg ·(m2 ·d)-1, respectively. PO43--P and NH4+-N were the main nutrients in the sediment released to the overlying water. The fluxes were high in the south and low in the north, and also high in the mouth of the Linhe River and downstream of the reservoir. Compared with similar studies, the fluxes at the sediment-water interface of Yuqiao Reservoir were relatively high, indicating that the sediment was an important source of nutrients for the overlying water in Yuqiao Reservoir.

Dietary Calcium and Phosphate levels affect bone development and mesenchymal stem cell lineage allocation in neonatal pigs

Deficits in bone deposition during early‐life have been associated with increased risk of osteoporosis later in life. Bone marrow mesenchymal stem cells (MSC) are a subset of multipotent stem cells residing within the bone which provide the life‐long supply of bone forming cells. Molecular mechanisms affecting the activity and differentiation potential of MSC are still poorly understood. Our previous work has revealed that the activity and differentiation potential of MSC are subject to alteration based on neonatal nutrition. Dietary calcium (Ca) and phosphate (PO4) levels play a critical role in regulation of bone development. With increasing interest in MSC therapies and an increasing incidence of bone diseases, we aimed to elucidate the impact of marginal dietary Ca and PO4 deficiency and excess on the activity and differentiation potential of MSC during neonatal development. During a 16‐day study, 27 neonatal pigs (n= 27, 24±6h old) were fed milk replacers that were isonitrogenous and isocaloric, but either 25% deficient (D), adequate (A), or 25% in excess (E) of Ca and PO4 requirements. Piglets were fed 8 times/d at a rate to match the growth rate of sow‐reared piglets. Body weight and feed intake were recorded daily. Blood was collected on d8 and d16 for analysis. Humeri were collected for the isolation of MSC and radial/ulna bones were collected for physical measurement and determination of bone mineral content. Serum PO4 concentrations were significantly higher in the A group compared to the D group on day 8, however at day 16 the D group had the highest serum PO4 concentrations with the E group having the lowest PO4 concentrations (P&lt;0.05). Serum FGF23 was greater in the D group than the E group at 16d (77.21±1.90 pg/mL vs. 70.38±1.90 pg/mL, P&lt;0.05), with values for the A group being intermediate to these groups. The D group had lower bone mineral content and bone volume as compared to the E group. Among the MSC, those isolated from D pigs had significantly lower rates of in vivo proliferation of than those isolated from A pigs, as determined by BrdU labelling (0.063±0.007 vs. 0.089±0.007), but significantly higher in vitro proliferation than those isolated from E pigs at both 12 and 24 h post‐plating (12 h: 0.40 ±0.04 vs 0.23±0.04; 24h: 0.28±0.04 vs 0.10±004). Ca and PO4 deficiency appears, based on the gene expression of key adipogenic factors as well as cellular accumulation of neutral lipids, to have predisposed MSC towards adipogenic differentiation. MSC from D pigs had increased expression of PPARγ2, FABP4, and LPL (P&lt;0.05) and greater accumulation of neutral lipids as indicated by Oil Red O staining. Coupled with this apparent predisposition for adipocytic differentiation, a decrease in osteogenic capabilities were seen among MSC isolated from D pigs. This was determined based on reduced expression of the osteogenic regulators osteocalcin and fibronectin at d6 post differentiation. These findings demonstrated that even minor dietary deficiencies of Ca and PO4 during the neonatal period can have a profound impact on bone development. These dietary deficiencies may also program future bone health by altering the differentiation capabilities of MSC.Support or Funding InformationThis project is support by USDA grantThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The responses of cucumber plants subjected to different salinity or fertilizer concentrations and reproductive success of Tetranychus urticae mites on these plants.

The plant stress hypothesis posits that a herbivore's reproductive success increases when it feeds on stressed plants, while the plant vigor hypothesis predicts that a herbivore preferentially feeds on more vigorous plants. We examined these opposing hypotheses by growing spider mites (Tetranychus urticae) on the leaves of stressed and healthy (vigorous) cucumber plants. Host plants were grown under controlled conditions at low, moderate, and high concentrations of NaCl (to induce salinity stress), at low, moderate, and high fertilizer concentrations (to support growth), and without these additions (control). The effects of these treatments were evaluated by measuring fresh and dry plant biomass, carotenoid and chlorophyll content, antioxidant enzyme activity, and concentrations of PO43-, K+, and Na+ in plant tissues. The addition of low concentrations of fertilizer increased dry mass, protein, and carotenoid content relative to controls, suggesting a beneficial effect on plants. The highest NaCl treatment (2560mgL-1) resulted in increased Na+ and protein content relative to control plants, as well as reduced PO43-, K+, and chlorophyll levels and reduced catalase and ascorbate peroxidase enzyme activity levels. Analysis of life table data of T. urticae mites raised on leaves from the aforementioned plant groups showed the intrinsic rate of increase (r) for mites was 0.167day-1 in control specimens, 0.125day-1 for mites reared on plants treated with a moderate concentration of fertilizer (10mLL-1), and was highest (0.241day-1) on plants grown under moderate salinity conditions (1920mgL-1 NaCl). Reproductive success of T. urticae did not differ on plants watered with a moderate concentration of NaCl or a high concentration of fertilizer. The moderately-stressed plants formed a favorable environment for the development and reproduction of spider mites, supporting the plant stress hypothesis.

Impact of Engineered Filter Bed Substrate Composition and Plants on Stormwater Remediation within a Rain Garden System1

Abstract Thirty-two rain-garden-engineered filter-bed substrates (EFBS) resulting from combinations of two substrate bases (sand and slate), two organic matter amendments [composted yard waste (CYW) and pine bark (PB)], two combination methods (banding and incorporation), and four combination amounts [2.5 cm/5%, 5.1 cm/10%, 7.6 cm/15%, and 10.2 cm/20% (by vol.)] were evaluated using three plant species (Betula nigra L. ‘Duraheat', Monarda fistulosa L. and Panicum virgatum L. ‘Shenandoah'). The impact of particle size distribution, saturated hydraulic conductivity (Ksat), volume of effluent, evapotranspiration, EFBS composition, and plant growth on water movement within a rain garden was determined. Sand EFBS maintained a numerically lower Ksat compared to slate EFBS regardless of composition. Using CYW and banding reduced effluent volume and increased evapotranspiration. Each EFBS was also evaluated for its ability to support plant growth and nutrient uptake. Shoot dry weight and shoot nutrient content (nitrogen and phosphorus) trends were similar and were highest for all species when grown in sand amended with banded CYW. Higher levels of total soluble nitrogen (TSN) were in the effluent from CYW compared to PB, regardless of substrate base. Sand generally had lower concentrations of TSN and PO4−3-P present in the effluent than slate. Index words: bioretention cell; saturated hydraulic conductivity (Ksat); effluent volume; effluent nutrient concentration; evapotranspiration; particle size distribution; total soluble nitrogen; ortho-phosphate; nitrate; ammonium. Species used in this study: ‘Duraheat' river birch (Betula nigra L.); wild bee balm (Monarda fistulosa L.); and ‘Shenandoah' switch grass (Panicum virgatum L.).

Groundwater nutrient inputs into an urbanized tropical estuary system in Indonesia

Groundwater discharge is known to transport nutrients into estuaries at several locations around the world. However, few studies report groundwater-associated nutrient fluxes from tropical developing regions such as Southeast Asia, even though this area shows the strongest human modifications in the coastal zone worldwide. We investigated groundwater nutrient flux into two streams and estuaries (Awur and Sekumbu Bay) in the urban area of Jepara, Indonesia, and its relation with the land usage surrounding the estuaries.We found that average concentrations of NO3, NH4, and PO4 in Jepara's aquifer reached 145μM, 68μM, and 14μM, respectively, and our results indicate that these were mainly originated from untreated sewage, agriculture, and manure input. Approximately 2200tonNyear−1 and 380tonPyear−1 were removed in the soil and aquifer before the nutrients were discharged into the river. The total groundwater discharge into the river and estuary was estimated to 461×103m3d−1, or up to 42% of the river discharge. Discharge of groundwater-associated NO3 (72×103mold−1), NH4 (34×103mold−1), PO4 (5×103mold−1), and additional surface runoff may contribute to eutrophication and a decrease of nearshore surface water quality. Nutrient concentrations in groundwater, river, and coastal seawater in the Jepara region are similar to those found in major urban areas in Southeast Asia, e.g. Manila and Bangkok, even though Jepara has smaller size and population. Thus, our results indicate that medium populated cities with highly modified regional land use can contribute a significant amount of nutrient discharge in the coastal area and should be included in global assessments of nutrient budget calculation.

A preliminary assessment of the geochemical factors affecting groundwater and surface water quality around the rural communities in Al-Anbar, Western Desert of Iraq

This study aims to assess the suitability of surface water and groundwater resources for irrigation and potable use by the rural communities in the Western Desert of Iraq. Sampling was conducted during the wet season (Jan 2012). Duplicate water and sediment samples were collected from the Euphrates River, connate water springs and meteoric groundwater. Water samples were analyzed for a suite of physicochemical parameters and heavy metals (Fe, Cu, Pb, Co, Cd and Ni). The H2S content of water samples was also determined as were heavy metals levels in riverine sediments. The water in the Euphrates River is fresh (701 ppm) dominated by Ca–Na–Cl ions with elevated concentrations of PO4, Pb and Cd (2.0, 0.023 and 0.02 ppm, respectively) due to the effects of agricultural land uses in the region. Shallow groundwater in the region is fresh to brackish due to the water–aquifer interaction that resulted in heterogeneity groundwater dominated by Cl, Ca–Mg–Cl and Ca–HCO3. Connate water springs in the region are associated with deep circulation of groundwater. Springs are characterized by brackish to saline water type dominated by Na–Cl and typically have acidic pH values. They are not suitable for irrigation or potable use due to the high TDS (7182 ppm) and dissolved H2S gas contents (120–865 ppm). Low concentrations of H2S gas (4.0 ppm) were detected in the Euphrates River, while they were not detected in the meteoric groundwater. The meteoric waters from the Euphrates River and some groundwater wells are suitable for potable use, but all are suitable for irrigation with attention to the potential-Mg hazard.

Water quality assessment in the Cherry Creek watershed: Patterns of nutrient runoff in an agricultural watershed

Access to safe, high quality water for consumption, agriculture, industry, and recreation is critically important. Continuous agricultural and mining activities have impaired the waters of the Grand Lake watershed in the central Great Plains region of the United States. The Grand Lake watershed encompasses portions of southeast Kansas, southwest Missouri, northwest Arkansas, and northeast Oklahoma, and drains into Grand Lake in northeast Oklahoma. The Cherry Creek watershed drains approximately 882.2 km2 (218,000 ac) of land in southeast Kansas and is a contributor of water to the Grand Lake watershed. This paper presents a water quality assessment in the Cherry Creek watershed, with an end toward mitigation of nonpoint source pollutants that are a major contributor to sediment and nutrient contaminants in Grand Lake. A hydrological model was developed using the Hydrological Simulation Program Fortran code and was updated, calibrated, and verified with measured data reported by US Geological Survey (USGS) and the Kansas Department of Health and Environment (KDHE). The model was extended to simulate water quality within the study area. Nitrate (NO3−-N), total ammonia (TAM), total phosphorus (TP), and orthophosphate (PO43−-P) concentrations measured at the USGS stations were used to calibrate the model, and concentrations reported by KDHE at downstream locations were used to verify the model. Results indicate good performance of the hydrological model as tests of fitness were within levels established in previous studies (root-mean-squared-error to standard deviation ratio [RSR] 0.6; NS > 0.5). Nutrient measurements below the minimum quantifiable limit (MQL) hampered precise simulation of nutrient changes, though simulated values were acceptable in terms of ranges of contaminant concentration values and seasonal trends. The calibrated model was used to estimate the probability that nutrient levels would exceed established water quality criteria for rivers and streams. Concentration values of NO3−-N and TAM are shown to be low for an agricultural watershed: 75% of the NO3−-N and TAM concentrations are lower than 0.41 mg L−1. The probability of NO3−-N and TAM concentrations being toxic for aquatic communities is lower than 9%. Although model-estimated PO43−-P concentrations were low in numerical value (ranging from 0 to 2.60 mg L−1), they could still promote eutrophication according to the accepted 0.05 mg L−1 criteria for maximum PO43−-P concentrations in streams. Concentrations of PO43−-P in Cherry Creek have a 30.4% probability of exceeding that threshold. Extensive use of animal manure (primarily poultry) or manure from cattle grazing on pasture may account for the elevated levels of PO43−-P observed in the watershed. Although nutrient runoff from agricultural watersheds is anticipated to be a major contributor to elevated stream nutrient loads, these results indicate minimal contamination from Cherry Creek.

Do cemeteries emit drugs? A case study from southern Germany.

The risk of earth burials for the environment and public health is a matter of controversial debate. The aim of the present study is to characterise the drainage of cemeteries with regard to the concentration of a number of pharmaceuticals and to the soil's hydrochemical properties, and to discuss these data in comparison with data obtained for surface waters located upstream of the cemeteries. Of the 12 drainage samples analysed using LC-ESI-MS/MS, seven contained carbamazepine (< 225ngl-1), five contained hydrochlorothiazide, one contained metoprolol (23ngl-1) and one contained traces of ibuprofen. The surface water samples contained a larger number of different drugs (8 of the 12 drugs under investigation) and higher concentrations (e.g. metropolol 2230ngl-1). The NO3, NH4, PO4 and DOC concentrations and the electrical conductivity of the cemetery drainages were in several samples higher than those of the surface water samples. The NO3 and NH4 concentrations exceeded the legal contaminant limits of drinking water in only one case. The present study found that the release of drugs and nutrients from cemeteries, measured in surface water drug loads, presents a low environmental risk. However, the study is only a snapshot and long-term monitoring of cemetery drainages, including a broad range of pharmaceuticals and detailed hydrological investigations, will have to be carried out before more substantiated statements can be made.