Matrix-bound Phosphine Concentrations Research Articles

Matrix-bound phosphine, phosphorus fractions and phosphatase activity through sediment profiles in Lake Chaohu, China

The distribution patterns of matrix-bound phosphine (MBP), phosphorus (P) fractions and neutral phosphatase activity (NPA) were investigated through five sediment profiles in Lake Chaohu, China. MBP was discovered in all sediment profiles within the concentration range of 1.58-50.34 ng kg(-1). These concentrations exhibited a consistent vertical distribution pattern in all profiles, and higher concentrations generally occurred in surface sediments. MBP concentrations showed a significant positive correlation with P fractions, total nitrogen (TN), Cu and Zn under lower levels of inorganic phosphorus (<0.6 g kg(-1)), organic phosphorus (<0.2 g kg(-1)), TN (<0.13%), Cu (<25 mg kg(-1)) and Zn (<150 mg kg(-1)), but no statistically significant correlations were obtained under higher levels. A multiple stepwise regression model ([MBP]=1.36[NPA]-6.21[pH]-0.06[Zn]+0.75[Cu]+49.86) was obtained between MBP concentrations and environmental variables, and MBP concentrations showed a strong positive correlation with NPA (P<0.0001). This indicates that the production of sediment MBP was controlled by microbially mediated processes in Lake Chaohu. This model could be used to predict MBP levels in the sediments. Our results indicate that MBP levels could not be used as indicators for the degree of lake eutrophication. The study of sediment MBP, P factions and NPA will improve our understanding of P cycling and their environmental significance in the eutrophic Lake Chaohu.

Matrix-bound phosphine and phosphorus fractions in surface sediments of Arctic Kongsfjorden, Svalbard: Effects of glacial activity and environmental variables

The surface sediments were collected from the glacial bay (GLAC), the central basin (CENTR) and their transition area (TRANS) along the fjord Kongsfjorden axis on Svalbard, Arctic, and matrix-bound phosphine (MBP), phosphorus fractions and alkaline phosphatase activity (APA) were analyzed. MBP was found in all the sediments with the concentration range of 8.93–59.45ngkg−1dw. The MBP levels in the CENTR sediments were two times higher than those in the GLAC and TRANS sediments, and the yield of phosphine (PH3) as a fraction of total phosphorus ranged from 1.78×10−8 to 3.53×10−8mgPH3mg−1P. The CENTR and TRANS sediments showed higher concentrations of total phosphorus (TP), organic phosphorus (OP) and APA than the GLAC sediments, indicating that glacial activity had an important effect on the spatial variability in the concentrations of MBP and phosphorus fractions. There existed a significant positive correlation (p<0.01) between MBP and seawater depths, OP, TP, APA, total organic matter, total nitrogen and total sulfur. The multiple stepwise regression model ([MBP]=16.1[OP]+18.6[APA]−26.1pH+221.3) was obtained between MBP concentrations and environmental variables. This model could be used to predict MBP levels in the sediments. Our results indicated that the production of MBP was associated with OP decomposition and microbially mediated factors in the sediments of Kongsfjorden in Arctic.

Occurrence of matrix-bound phosphine in polar ornithogenic tundra ecosystems: Effects of alkaline phosphatase activity and environmental variables

Phosphine (PH 3), a reduced phosphorus compound, is a highly toxic and reactive atmospheric trace gas. In this study, a total of ten ornithogenic soil/sediment profiles were collected from tundra ecosystems of east Antarctica and Arctic, and matrix-bound phosphine (MBP), the phosphorus fractions and alkaline phosphatase activity (APA) were analyzed. High MBP concentrations were found in these profiles with the range from 39.59 ng kg − 1 dw to 11.77 μg kg − 1 dw. MBP showed a consistent vertical distribution pattern in almost all the soil profiles, and its concentrations increased at soil surface layers and then decreased with depths. MBP levels in the ornithogenic soils were two to three orders of magnitude lower than those in ornithogenic sediments. The yield of PH 3 as a fraction of total P in all the profiles ranged from 10 − 5 to 10 − 9 mgPH 3 mg − 1 P with higher mean PH 3 yield in the ornithogenic sediments. The ornithogenic soils showed high concentrations of total phosphorus (TP), organic phosphorus (OP), inorganic phosphorus (IP) and metal elements (Cu, Zn, Mn, Fe, Al and Ca) but low MBP levels, vice versa for the ornithogenic sediments. No correlation had been obtained between MBP concentrations and IP, OP and TP. There existed an exponential correlation (r = 0.67, p < 0.01) between MBP and soil/sediment moisture. MBP concentrations showed a significant positive correlation with APA (r = 0.668, p < 0.0001), total organic carbon (r = 0.501, p < 0.0001), total hydrogen (r = 0.483, p < 0.0001) and total sulfur (r = 0.398, p < 0.001), indicating that the production of MBP is associated with microbially mediated factors rather than the contents of TP, IP and OP in the P-enriched ornithogenic soils/sediments. Our results indicated that MBP is an important gaseous link in the phosphorus biogeochemical cycles of ornithogenic tundra ecosystems in Antarctica and Arctic.

Matrix-bound phosphine in sediments from Lake Illawarra, New South Wales, Australia

Matrix-bound phosphine (MBP) has been measured in sediment from two cores in Lake Illawarra on the south east coast of Australia. The sediments were also dated in the upper layers. MBP concentrations found range from 142 to 1813ngkg−1, dw (dry weight of sediment) with some values being amongst the highest ever measured. Values of MBP in deeper sediments were higher than for near surface samples, but the patterns with depth were not consistent. Strong correlations were noted between MBP and organic phosphorus (OP, r>0.8) and with total phosphorus (TP, r>0.7), but only moderate correlations were found with organic carbon (OC, r>0.5). No correlations were found between MBP concentrations and the age of the sediments. It was confirmed that high MBP concentrations are indicative of a phosphorus rich environment. The results tend to support the premise that MBP is generated by microbial attack on OP under anaerobic conditions.

Matrix-bound phosphine in paddy fields under a simulated increase in global atmospheric CO2

Environmental context. Although phosphine (PH3) is an important gaseous carrier in the phosphorus cycle, its production and environmental behaviour remain unclear. Paddy fields are thought to be one of the main sources responsible for the production and emission of PH3. Understanding the behaviour of PH3 in paddy fields under elevated CO2 concentration is crucial in understanding the phosphorus cycle and its response to rising global atmospheric CO2 concentration. Abstract. The behaviour of matrix-bound phosphine (MBP) in paddy fields under elevated [CO2] (ambient + 200 μmol mol–1) is investigated to understand the soil phosphorus cycle and its link to increasing global atmospheric [CO2]. MBP concentrations range from 17.0 ± 5.8 to 1035 ± 331 ng kg–1. Concentrations at the transplanting and harvest stages are significantly higher than during the growing stages. The MBP level (212 ± 61 ng kg–1) under elevated [CO2] is slightly higher than under ambient [CO2] (189 ± 44 ng kg–1). Root exudates and addition of inorganic phosphate fertiliser speed up the production of MBP, whereas fast paddy growth and increasing air temperature accelerate the emission of MBP into the atmosphere. Significant positive correlations are found between MBP and inorganic phosphorus and organic matter, indicating that MBP may be produced from the microbial reduction of inorganic phosphorus in paddy fields.

Distribution of phosphine in the offshore area of the Southwest Yellow Sea, East Asia

Phosphine is a natural gaseous compound in the phosphorus biogeochemical cycle. This paper studies the spatial and temporal distributions of matrix-bound phosphine (MBP) and gaseous phosphine in the offshore area of the Southwest Yellow Sea, East Asia. The results show that MBP concentrations in marine surface sediments range from 0.69 ± 0.06 ng/kg (dry) to 179 ± 29 ng/kg (dry). Higher seasonal MBP concentrations in sediments are found in fall than in spring or winter in most sites. High MBP contents are observed in two fish-breeding areas. MBP concentrations decrease with distance to the coast, except in the southeast of the sampling area. MBP levels in marine sediments are found to be higher than those at several other places: freshwater sediments and soil, except eutrophic lakes. Gaseous phosphine contents in fall range from 0.14 ± 0.00 ng/m 3 to 9.83 ± 0.97 ng/m 3. No correlation is observed between MBP and gaseous phosphine.

Occurrence of matrix-bound phosphine in intertidal sediments of the Yangtze Estuary

This study investigated the levels and potential transformation of matrix-bound phosphine in the intertidal sediments (0–5 cm) of the Yangtze Estuary. Matrix-bound phosphine concentrations in sediments ranged from 0.65 to 3.25 ng kg −1, with an annual average of 1.53 ng kg −1. In freshwater sediments, the concentrations of matrix-bound phosphine were significantly higher than in the brackish sediments. The maximum concentrations of matrix-bound phosphine appeared in July (1.17–3.25 ng kg −1), followed by May (0.92–3.01 ng kg −1), November (0.65–2.41 ng kg −1) and January (0.51–1.42 ng kg −1). Matrix-bound phosphine derived probably from the mechanochemical reduction of apatite-bound phosphate and the microbial conversion of organic phosphorus in the intertidal sediments. Its spatial and seasonal distributions, however, were regulated by salinity and sediment temperature. Compared with other aquatic systems (e.g. rivers, lakes and coastal seas), a low level of matrix-bound phosphine was observed in the intertidal sediments, probably implicating a relatively rapid turnover of phosphine in the system.

Distribution characteristics of matrix-bound phosphine along the coast of China and possible environmental controls

Matrix-bound phosphine (MBP) concentrations in surface sediments collected from 37 stations along the coast of China in 2006 are reported. MBP was found in all samples and the average concentration was 6.30 ng kg −1 dry weight (dw). The distribution of MBP showed certain spatial variation characteristics with high MBP concentrations at stations near to the coast. The average concentrations of MBP in the northern Yellow Sea (NYS), the southern Yellow Sea (SYS), the northern area of East China Sea (NECS), the southern area of East China Sea (SECS), and South China Sea (SCS) were 5.57 ± 3.78, 3.78 ± 2.81, 5.27 ± 3.07, 5.48 ± 4.05 and 13.52 ± 7.86 ng kg −1 dw, respectively. The correlations between MBP and influencing factors, such as the sedimentary environmental characteristics (sediment type, the grain size, contents of phosphorous, organic matters and redox potential) and the aquatic environmental characteristics (temperature, salinity, depth and hydrodynamics) were studied. The results indicated that MBP was strongly influenced by various factors, such as total phosphorus (TP), organic phosphorus (OP), organic carbon (OC), the grain size and hydrodynamics, all of which not only offered reasonable interpretations for the distribution characteristics of MBP but also provided evidence to support the viewpoint that phosphine originated from OP decomposition. This work is the first comprehensive study of the distribution of MBP along the coast of China and its relationships with environmental factors which will lead to a better understanding of the phosphorus (P) biogeochemical cycle in the sea.

Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4–12. The rates of phosphine production and release from lake sediments varied with temperature. 20°C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes.

Matrix-bound phosphine in Antarctic biosphere

Phosphine (PH 3) is a natural gaseous carrier of phosphorus in its geochemical cycles, and it might be of importance to the phosphorus balance of natural ecosystem. For the first time phosphine levels were investigated in the Earth’s coldest, driest, and most southerly Antarctic biosphere. Matrix-bound phosphine (MBP) was found in sea animal guanos, ornithogenic sediments and soils. Phosphine concentrations varied with different sea animal guanos. Average phosphine concentrations in empire penguin, gentoo penguin, sea lion, skua and gull guanos were 2.54 ± 1.28 ng kg −1, 6.21 ± 2.15 ng kg −1, 9.12 ± 4.66 ng kg −1, 11.90 ± 1.29 ng kg −1 and 14.55 ± 6.74 ng kg −1, respectively. The contents of phosphorus in these various matrixes have an important effect on MBP concentrations. The levels of phosphine appeared an increasing tendency with the content of TP, IP and OP in sea animal guanos, ornithogenic sediments or soils. The correlation between PH 3 and Fe, Mn, Al in these matrixes was also analyzed and discussed. Phosphine showed an obviously positive correlation with Fe in sea animal guanos. However, excessively high Fe, Al and Mn may inhibit the formation of PH 3 in the ornithogenic soils or sediments in the Antarctic biosphere.

Matrix bound phosphine formation and depletion in eutrophic lake sediment fermentation—simulation of different environmental factors

Closed anaerobic batch-fermentation of eutrophic lake sediment samples was performed under variation of four environmental fermentation factors (pH, temperature, water/sediment ratio and disturbance) to learn how the quantity of phosphine will change and if the quantity of phosphine can increase. The fermentation conditions where matrix bound phosphine (MBP) increased (doubled from 3 193±520 to about 7 982±1003 ng/kg) were: a pH of 8 and of 10 (as compared to 1, 2, 4, 6, 12), a temperature of 20 and 30 °C (as compared to 4 and 40 °C), a water/sediment ratio of 3:1 (as compared to 1:1, 2:1, 5:1) and a disturbance of 100 r/min (as compared to 0 r/min), respectively. Although, over the full time course of fermentation, the balance of phosphine production became negative again or did remain almost unchanged under most conditions. A pH of 1 or disturbance of 150 r/min was significant factors to decrease phosphine over the long term. Free phosphine had been detected but was of minor importance (in the order of 60.9±10.1 ng/m 3). Overall, the fermentation conditions which had been most favorable for microbial life (moderate temperature (20 and 30 °C) and pH 8) were also most favorable for a positive phosphine balance. This is an indication, but no biochemical proof that a natural (biogenic, microbial, biochemical) NET PRODUCTION of phosphine or DE NOVO PRODUCTION of phosphine has occurred. MBP concentrations in lake sediments were discussed as to be strongly dependent on a balance of natural generation and depletion processes, dependent of the simulated parameters.