Comparison of phosphorus fraction distribution and influencing factors of suspended and surface sediments in the Tiaoxi watershed, China

Suspended and surface sediments from the Tiaoxi watershed, fed by the Xitiaoxi and Dongtiaoxi rivers, were analyzed for total phosphorus (TP) and the inorganic P fractions of loosely adsorbed P that were extractable with NH4Cl (NH4Cl-P), reductant P (BD-P), metal oxide-bound P extractable with NaOH (NaOH-P), and calcium-bound, HCl-extractable P (HCl-P), while other physicochemical compositions were also determined. The spatial variations of P fractions in these sediments were investigated, and the major factors influencing the various fractions were explored by multivariate statistics. Compared to surface sediments, suspended sediments contained considerably higher concentrations of total nitrogen, TP, organic matter, Al, Fe, Mn and biologically available P (BAP, given as NH4Cl-P, BD-P and NaOH-P combined) and lower concentrations of Si, Ca and HCl-P in the studied catchments. Dongtiaoxi sediments had higher TP, inorganic phosphorus and HCl-P concentrations and a lower BAP content compared with Xitiaoxi sediments, trends that were associated with local geological backgrounds, landscapes and anthropogenic characteristics. The results of principal component analysis showed different effects of sediment properties on P fraction distributions for Xitiaoxi and Dongtiaoxi sediments. The sediment components and structure exert a strong influence on BAP in Xitiaoxi sediments, in contrast to Dongtiaoxi sediments, where P fractions are mainly affected by urbanization and other anthropogenic activities such as shipping.

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Distributions of phosphorus fractions in the sediments of a river–lake system: a case study in Huai River catchment area, China

Water Science & Technology ◽

10.2166/wst.2015.278 ◽

2015 ◽

Vol 72 (5) ◽

pp. 824-834 ◽

Cited By ~ 2

Author(s):

Piao Jingqiu ◽

Tang Changyuan ◽

Song Xianfang

Keyword(s):

Grain Size ◽

Catchment Area ◽

Sediment Characteristics ◽

P Fractions ◽

River Catchment ◽

Lake System ◽

Hongze Lake ◽

Huai River ◽

Fraction Distribution ◽

P Fraction

Phosphorus (P) forms, with respect to sediment characteristics, and an in-stream sluice were studied in the river–lake system, Huai River catchment area, China. The mean of total P in sediments in the mainstream of the Huai River was higher than that in the Hongze Lake. It was found that P fractions varied in the sediments throughout the river and lake. Detrital-P was the dominant P fraction in the mainstream and organic P and detrital-P were the dominant P fractions in the lake, which could indicate: biologically available and non-biologically available forms. Useful information for the interpretation of P fractions could also be obtained from major sediment characteristics. Whether the relations between P fractions and grain size characteristics were significant or weak, 0.125 mm was a threshold grain size for P fraction distribution in sediment. In addition, the Bengbu Sluice, one of the most important in-stream facilities in the Huai River catchment area, regulated not only the transport of P in sediments upstream and downstream of the sluice, but also the distribution of P fractions in the river–lake system. Therefore, it was confirmed that nutrient loadings could be prevented from reaching the watershed, as well as improved ecological diversity by integrating sluice operation.

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Effect of cumulative fertilizer dressings on the phosphorus status of mineral soils I Changes in inorganic phosphorus fractions

Agricultural and Food Science ◽

10.23986/afsci.72352 ◽

1989 ◽

Vol 61 (2) ◽

pp. 55-59 ◽

Cited By ~ 1

Author(s):

Helinä Hartikainen

Keyword(s):

Inorganic Phosphorus ◽

Soluble Form ◽

P Fertilization ◽

P Fractions ◽

Inorganic P ◽

Extractable P ◽

Inorganic P Fractions ◽

Phosphorus Status ◽

Mineral Soils ◽

Inorganic Phosphorus Fractions

Surface soil samples were collected from 16 P fertilization trials before onset of the experiments and after seven years of cultivation. The changes in the inorganic P fractions were investigated in plots amended annually with 0, 30 or 60 kg of P ha-1. In the clay soils, cultivation without P fertilization depleted the NH4F-extractable and NaOH-extractable P reserves by 22—69 kg ha-1 ; in the coarser soils, the respective depletion was 8—140 kg ha-1. H2S04-soluble P decreased in seven soils by 16—34 kg ha-1. In the plots amended totally with 210 or 420 kg of P ha-1, on the other hand, these P fractions increased by 24—174 and 46—368 kg ha-1, respectively. The higher the P dressing was, the more the added P tended to accumulate in the fluoride-soluble form as compared to the alkali-soluble form.

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The chemical characteristics of soil which determine phosphorus partitioning in highly calcareous soils

Journal of the Serbian Chemical Society ◽

10.2298/jsc0611219t ◽

2006 ◽

Vol 71 (11) ◽

pp. 1219-1236 ◽

Cited By ~ 4

Author(s):

Ana Topalovic ◽

Lidija Pfendt ◽

Natalija Perovic ◽

Dragana Djordjevic ◽

Snezana Trifunovic ◽

...

Keyword(s):

Calcareous Soils ◽

Principal Component ◽

Chemical Characteristics ◽

P Fractions ◽

Related Factors ◽

Oxide Hydroxide ◽

The Status ◽

P Fraction ◽

Definition Of ◽

Total P

Phosphorus fractions from three highly calcareous soils (average, 24.9 ? 4.8 %CO3 2-) from sampling sites with a Mediterranean climate were isolated by sequential extraction. In order to provide a more reliable basis for the definition of the obtained P-fractions, principal component analysis was applied and from the chemical characteristics of the 14 investigated soils, those characteristics which define the content and association features of the P-fractions were assessed. The soils are characterized by a relatively high pH (8.0 - 8.2) and by significantly differing contents of organic mater, acid-soluble Mg and total P. These differences affected the various association features of the P-fraction with the soil constituents. The NH4F-P fraction (isolated with 0.5 M NH4F, pH 8.2) is defined by the contents of the main metals of the oxide-hydroxide- clay associations (Al, Fe,Mn) or by the the redox potential (Eh) of Mn. The accumulation of NaOH-phosphorus (extractable with 0.1M NaOH) depended on the constituents of the oxide-hydroxide-clay association, the humic substances and Eh-related factors. In those soils in which NaOH-Pis defined by the oxide-hydroxide-clay association, the participation of Fe as a bridge-forming metal is proposed. The main part of total P, i.e., ?P = TP - (NH 4F-P + NaOH-P) is defined by the status of Mn- and Fe-humic complexes or by the concentration of hydroxyl-ions.

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The influences of historic lake trophy and mixing regime changes on long-term phosphorus fraction retention in sediments of deep eutrophic lakes: a case study from Lake Burgäschi, Switzerland

Biogeosciences ◽

10.5194/bg-17-2715-2020 ◽

2020 ◽

Vol 17 (10) ◽

pp. 2715-2729 ◽

Cited By ~ 2

Author(s):

Luyao Tu ◽

Paul Zander ◽

Sönke Szidat ◽

Ronald Lloren ◽

Martin Grosjean

Keyword(s):

Trophic State ◽

Surface Sediments ◽

P Fractions ◽

Deep Lakes ◽

Eutrophic Lakes ◽

P Fraction ◽

Labile P ◽

Total P ◽

P Retention

Abstract. Hypolimnetic anoxia in eutrophic lakes can delay lake recovery to lower trophic states via the release of sediment phosphorus (P) to surface waters on short timescales in shallow lakes. However, the long-term effects of hypolimnetic redox conditions and trophic state on sedimentary P fraction retention in deep lakes are not clear yet. Hypolimnetic withdrawal of P-rich water is predicted to diminish sedimentary P and seasonal P recycling from the lake hypolimnion. Nevertheless, there is a lack of evidence from well-dated sediment cores, in particular from deep lakes, about the long-term impact of hypolimnetic withdrawal on sedimentary P retention. In this study, long-term sedimentary P fraction data since the early 1900s from Lake Burgäschi provide information on benthic P retention under the influence of increasing lake primary productivity (sedimentary green-pigment proxy), variable hypolimnion oxygenation regimes (Fe∕Mn ratio proxy), and hypolimnetic withdrawal since 1977. Results show that before hypolimnetic withdrawal (during the early 1900s to 1977), the redox-sensitive Fe∕Mn-P fraction comprised ∼50 % of total P (TP) in the sediment profile. Meanwhile, long-term retention of total P and labile P fractions in sediments was predominantly affected by past hypolimnetic redox conditions, and P retention increased in sedimentary Fe- and Mn-enriched layers when the sediment-overlaying water was seasonally oxic. However, from 1977 to 2017, due to eutrophication-induced persistent anoxic conditions in the hypolimnion and to hypolimnetic water withdrawal increasing the P export out of the lake, net burial rates of total and labile P fractions decreased considerably in surface sediments. By contrast, refractory Ca–P fraction retention was primarily related to lake primary production. Due to lake restoration since 1977, the Ca–P fraction became the primary P fraction in sediments (representing ∼39 % of total P), indicating a lower P bioavailability of surface sediments. Our study implies that in seasonally stratified eutrophic deep lakes (like Lake Burgäschi), hypolimnetic withdrawal can effectively reduce P retention in sediments and potential for sediment P release (internal P loads). However, after more than 40 years of hypolimnetic syphoning, the lake trophic state has not improved nor has lake productivity decreased. Furthermore, this restoration has not enhanced water column mixing and oxygenation in hypolimnetic waters. The findings of this study are relevant regarding the management of deep eutrophic lakes with mixing regimes typical for temperate zones.

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Bottom sediments as a potential source of phosphorus in the riverine-lacustrine system of the Kośna River (Northeastern Poland)

Limnological Review ◽

10.2478/v10194-011-0051-7 ◽

2012 ◽

Vol 12 (3) ◽

pp. 115-124 ◽

Cited By ~ 3

Author(s):

Izabela Bigaj ◽

Michał Łopata ◽

Julita Dunalska ◽

Daniel Szymański ◽

Rafał Zieliński

Keyword(s):

Rank Order ◽

Inorganic Phosphorus ◽

P Fractions ◽

Iron Compounds ◽

Inorganic P ◽

Potential Source ◽

Northeastern Poland ◽

P Fraction ◽

Labile P ◽

P Budget

AbstractSediments from hypereutrophic Lake Łajskie localized in northeastern Poland were examined on the basis of P-fraction. The sediments were collected at five sampling sites. In the investigated lake, the rank order of P-fractions was HCl-P > BD-P > NH4Cl-P > NaOH - nrP. The loosely sorbed phosphorus NH4Cl-P represented < 3% of the sedimentary inorganic phosphorus, while the reductant phosphorus (BD-P) ranged from 2 to 10%. The calcium bound phosphorus (HCl-P) showed considerable contribution (59-74%) to the sedimentary inorganic P-loads. BDP was the most reactive fraction in Lake Łajskie. Iron compounds and organic matter seem to play a significant role in regulating this labile P-budget.

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Hydrogeochemical evolution processes and evaluation of groundwater suitability for domestic and agricultural utility in Southern Punjab, Pakistan

10.21203/rs.3.rs-536324/v1 ◽

2021 ◽

Author(s):

Javed Iqbal ◽

Chunli Su

Keyword(s):

Environmental Changes ◽

Major Ions ◽

Anthropogenic Activities ◽

Human Life ◽

Principal Component ◽

Weathering Processes ◽

Groundwater Samples ◽

Groundwater Hydrochemistry ◽

And Cluster Analysis ◽

Major Factors

Abstract Groundwater is a vital resource for human life and economic growth. In the Khanewal district of Punjab, Pakistan, environmental changes, and anthropogenic activities have made groundwater extremely vulnerable in the past forty years. Sixty-eight groundwater samples were collected from the study area, major ions and trace elements were analyzed. The Principal Component Analysis and Cluster Analysis were used to identify the major factors influencing groundwater quality, as well as to assess its suitability for drinking and irrigation in southern Punjab. The aquifers are slightly acidic to alkaline, according to the pH (6.9–9.2) of groundwater. Significant cations are distributed as follows: Na+ > Ca2+ > Mg2+ > K+, while anions are distributed as HCO3− > SO42− > Cl−. The main hydrochemical facies are mixed Na·Ca-HCO3 and Na·Ca (Mg)-HCO3·SO4. Rock weathering processes, such as the dissolution of calcite, dolomite, and gypsum minerals, governed groundwater hydrochemistry. The water quality index (WQI) indicates that 17.64% of the water samples are unsuitable to drink. However, according to the Wilcox diagram, the USSL diagram, and some other agricultural indices, approximately 68% of the groundwater samples are suitable for irrigation.

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Influence of Application of Organic Residues of Different Biochemical Quality on Phosphorus Fractions in a Tropical Sandy Soil

Agronomy ◽

10.3390/agronomy11020248 ◽

2021 ◽

Vol 11 (2) ◽

pp. 248

Author(s):

Tanabhat-Sakorn Sukitprapanon ◽

Metawee Jantamenchai ◽

Duangsamorn Tulaphitak ◽

Nattaporn Prakongkep ◽

Robert John Gilkes ◽

...

Keyword(s):

Leaf Litter ◽

Sandy Soil ◽

Organic Residue ◽

Residue Quality ◽

Organic Residues ◽

P Fractions ◽

Residual P ◽

Extractable P ◽

P Fraction ◽

Labile P

Understanding phosphorus (P) dynamics in tropical sandy soil treated with organic residues of contrasting quality is crucial for P management using organic amendments. This research determined P fractions in a tropical sandy soil under the application of organic residues of different quality, including groundnut stover (GN), tamarind leaf litter (TM), dipterocarp leaf litter (DP), and rice straw (RS). The organic residues were applied at the rate of 10 t DM ha−1 year−1. The P fractions were examined by a sequential extraction procedure. Organic residue application, regardless of residue quality, resulted in P accumulation in soils. For unamended soil, 55% of total P was mainly associated with Al (hydr)oxides. Organic residue application, regardless of residue quality, diminished the NH4F-extractable P (Al-P) fraction, but it had a nonsignificant effect on NaOH-extractable P (Fe-P). The majority of Al-P and Fe-P fractions were associated with crystalline Al and Fe (hydr)oxides. NH4Cl-extractable P (labile P), NaHCO3-extractable P (exchangeable P and mineralizable organic P), HCl-extractable P (Ca-P), and residual P fractions in soil were significantly increased as a result of the incorporation of organic residues. The application of organic residues, particularly those high in ash alkalinity, increase soil pH, labile P, and Ca-P fractions. In contrast, applications of residues high in lignin and polyphenols increase residual P fraction, which is associated with organo-mineral complexes and clay mineral kaolinite.

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Predicting current and future background ion concentrations in German surface water under climate change

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2018.0004 ◽

2018 ◽

Vol 374 (1764) ◽

pp. 20180004 ◽

Cited By ~ 11

Author(s):

Trong Dieu Hien Le ◽

Mira Kattwinkel ◽

Klaus Schützenmeister ◽

John R. Olson ◽

Charles P. Hawkins ◽

...

Keyword(s):

Climate Change ◽

Surface Waters ◽

Anthropogenic Activities ◽

Global Environmental Change ◽

Running Water ◽

Ion Concentrations ◽

Freshwater Organisms ◽

Global Environmental Issue ◽

Global Environmental ◽

Major Factors

Salinization of surface waters is a global environmental issue that can pose a regional risk to freshwater organisms, potentially leading to high environmental and economic costs. Global environmental change including climate and land use change can increase the transport of ions into surface waters. We fit both multiple linear regression (LR) and random forest (RF) models on a large spatial dataset to predict Ca 2+ (266 sites), Mg 2+ (266 sites), and (357 sites) ion concentrations as well as electrical conductivity (EC—a proxy for total dissolved solids with 410 sites) in German running water bodies. Predictions in both types of models were driven by the major factors controlling salinity including geologic and soil properties, climate, vegetation and topography. The predictive power of the two types of models was very similar, with RF explaining 71–76% of the spatial variation in ion concentrations and LR explaining 70–75% of the variance. Mean squared errors for predictions were all smaller than 0.06. The factors most strongly associated with stream ion concentrations varied among models but rock chemistry and climate were the most dominant. The RF model was subsequently used to forecast the changes in EC that were likely to occur for the period of 2070 to 2100 in response to just climate change—i.e. no additional effects of other anthropogenic activities. The future forecasting shows approximately 10% and 15% increases in mean EC for representative concentration pathways 2.6 and 8.5 (RCP2.6 and RCP8.5) scenarios, respectively. This article is part of the theme issue ‘Salt in freshwaters: causes, ecological consequences and future prospects’.

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Person - job fi t and the work commitment of IT Personnel

Journal of Human Growth and Development ◽

10.7322/jhgd.119277 ◽

2016 ◽

Vol 26 (2) ◽

pp. 218 ◽

Cited By ~ 2

Author(s):

Therasa C. ◽

C. Vijayabanu

Keyword(s):

Regression Analysis ◽

Principal Component ◽

Attrition Rate ◽

P Value ◽

Work Commitment ◽

Key Factors ◽

Coeffi Cients ◽

Work Autonomy ◽

Major Factors ◽

The Impact

Introduction: There have been given a much higher importance to employee commitment and retention since India is experiencing the highest attrition rate globally Economic Times, 2015. Hence, considering the factors of Person-job fi t to interpret the impact towards work commitment is very well essential, especially in the current scenario. Work Commitment is a vital element in any organization which has outstanding impact on productivity and functioning and hence it is very much vital to have a committed workforce which is necessary in this competitive environment and tight labour market. In the same way, there is considerable amount of evidence that if P-J fi t is high then it will have a direct impact on organization commitment also. Person-job fi t is the compatibility between person’s competency and abilities and the requirements of the job Zheng et al.2. If there exists a mismatch between person-job fi t then the consequences might result in poor work commitment, low job satisfaction and extremely lower involvement in the job. Objective: This study analyzed the key factors that contribute to Person- job compatibility among IT workers and also analyzed the relationship and impact of Person- job compatibility towards work commitment. Methods: Exploratory Factor Analysis (EFA) was used to fi lter the key factors initially, followed by a linear regression technique to determine the impact of Person- job compatibility factors in work commitment on a sample of 300 employees. EFA used Principal Component analysis for extraction and Promax for rotation. Finally regression analysis was carried out to predict the work commitment through statistically significant person-job compatibility variables. Results: The impact of person-job compatibility on work commitment was studied through regression analysis and it imply that for every unit increase in HR Policy, a 0.52 (unstandardised coeffi cients) increase in work commitment is predicted and it has been turned out as a most impacting variable to predict work commitment. The coeffi cients for Relationship (B =.330, sig =.000), HR Policies (B =.519, sig =.000), Pay and Benefi ts (B =.386, sig =.000) and Employee Growth (B =.290, sig =.001) were statistically significant, since its p-value is .000 which is smaller than .05. The coeffi cients for Work Autonomy (B =.154, sig = .081) was not statistically signifi cant, since its p-value is 0.081 which is greater than.05. Conclusion: The major factors responsible for creating work commitment among IT employees are Relationship, HR Policies and strategies, Pay and benefi ts, Work autonomy and Employee growth. The most contributing regressors which accounts for creating work commitment are HR policies, Pay and benefi ts, Employee growth and work autonomy.

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Geochemical and statistical evaluation of groundwater in the Thamirabarani river basin, south India

10.21203/rs.3.rs-163816/v1 ◽

2021 ◽

Author(s):

Gajendran Chellaiah ◽

Basker ◽

Hima Pravin ◽

Suneel Kumar Joshi ◽

Sneha Gautam

Keyword(s):

River Basin ◽

Tamil Nadu ◽

Statistical Evaluation ◽

Anthropogenic Activities ◽

Monsoon Season ◽

Principal Component ◽

Chloride Ion ◽

Temporal Analysis ◽

Point Sources ◽

International Standards

Abstract In the present study, an attempt has been made to develop the dictate metrics using a multi-proxy approach, i.e., spatial-temporal analysis, statistical evaluation, and hydrogeochemical analysis for 45 water samples located in the Thamirabarani river basin in Tamil Nadu, India. In order to evaluate the aptness of developed metrics for agriculture and domestic needs, eleven years dataset was analyzed and compared with national and international standards. Monitoring and analysis results revealed that the concentration of calcium and chloride ion was on the higher side in all the selected locations. These higher values may be attributed to the regional point sources such as untreated water disposal and off-peak sources such as agriculture practices. The principal component analysis resulted in 84.2% of the total variance in the post-monsoon season dataset. The major analyzed cations and anions were observed in the following order: Na+> Ca2+> Mg2+> K+ and Cl−> HCO3−> SO42−> NO3−, respectively. Overall, this study revealed that the studied area's groundwater quality was significantly affected by the high salinity in the region, probably due to anthropogenic activities and unprotected river sites.

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