ADSORÇÃO DE FÓSFORO EM SOLOS DE REGIÕES TROPICAIS

O fósforo (P) é o nutriente mais limitante ao cultivo nos solos tropicais, que, geralmente, apresentam alta capacidade de adsorção de P. Alguns atributos químicos e físicos do solo como o teor de argila, pH, CTC efetiva e matéria orgânica influenciam na dinâmica de adsorção. O objetivo deste estudo foi avaliar o processo de adsorção do fósforo em um Latossolo Vermelho Amarelo (LVA) e um Neossolo Quartzarênico (RQ) da região de transição Cerrado-Amazônia, e avaliar os atributos dos solos que influenciam na dinâmica de adsorção do P. Os ensaios de sorção foram realizados pelo método “Batch” ou em batelada e à partir dos dados obtidos foram construídas curvas obtendo a equação linearizada de Langmuir, com as quais foram determinados os valores de capacidade máxima de adsorção de P (CMAP), a constante relacionada com a energia de ligação (KL) e o fator capacidade de P máximo (FCPmáx). Houve diferença na CMAP, KL e FCPmáx dos solos estudados, sendo que os maiores valores foram encontrados no LVA, devido principalmente ao maior teor de argila em relação ao RQ. A matéria orgânica foi um dos poucos atributos que tiveram correlação negativa com os atributos de adsorção, ressaltando sua importância no manejo para aumentar a eficiência da adubação fosfatada. Palavras-chave: Latossolo Vermelho Amarelo; Neossolo Quartzarênico; Isotermas de adsorção. Phosphorus adsorption in soils of tropical regions ABSTRACT: Phosphorus (P) is the most limiting nutrient for cultivation in tropical soils, as they generally have high P adsorption capacity. Some chemical and physical attributes of soil such as clay content, pH, effective cation exchange capacity (ECEC) and organic matter influence the adsorption dynamics. The objective of this study was to evaluate the behaviour of the phosphorus adsorption process in a Red-Yellow Latosol and a Quartzarenic Neosol from the Cerrado-Amazon transition region, and to evaluate the soil attributes that influence the adsorption dynamics of the soil of the phosphorus. Sorption tests were performed using the “Bach” method, from the Langmuir linearized equation, the maximum P adsorption capacity (MPAC), the constant with the binding energy (KB) and the maximum capacity factor (PCFmax) were selected. There was a difference in MPAC, KB and PCFmax of the studied soils, and the highest values were found in the Red-Yellow Oxisol, mainly due to the higher clay content in relation to theTypic Quartzipisamment. Organic matter was one of the few attributes that had a negative correlation with the adsorption attributes, highlighting (emphasizing) it’s importance in (soil) management to increase the efficiency of phosphate fertilization. Keywords: Red-Yellow Latosol; Quartzarenic Neosol; adsorption isotherms.

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Linking phosphorus sorption and magnetic susceptibility in clays and tropical soils

Soil Research ◽

10.1071/sr20099 ◽

2020 ◽

Vol 58 (5) ◽

pp. 430 ◽

Cited By ~ 1

Author(s):

G. C. Poggere ◽

V. Barrón ◽

A. V. Inda ◽

J. Z. Barbosa ◽

A. D. B. Brito ◽

...

Keyword(s):

Magnetic Susceptibility ◽

Adsorption Capacity ◽

Tropical Soils ◽

Maximum Adsorption Capacity ◽

Phosphorus Sorption ◽

P Adsorption ◽

Opposite Trend ◽

Adsorption Data ◽

The Relationship ◽

P Desorption

Maghemite (Mh) and magnetic susceptibility have been little studied in relation to phosphorus (P) sorption, despite the fact that tropical soils – particularly those derived from mafic rocks – may contain substantial amounts of this iron oxide. In this work, we investigated the relationship between P adsorption and magnetic susceptibility in tropical soils, and determined the maximum adsorption capacity of P (MACP) and P desorption in seven pedogenic clays from magnetic soils with contrasting parent materials and three synthetic Mh samples. Considering the heterogeneity of the soil dataset in this study, the exclusive adoption of magnetic susceptibility as an indicator of P adsorption potential in soil remains uncertain. The relationship between magnetic susceptibility and adsorbed P was more evident in the B horizon of red soils from basic igneous rocks. In this group, soils with magnetic susceptibility above 20 × 10−6 m3 kg−1 had high adsorbed P. Although the pedogenic clays exhibited lower MACP values (1353–2570 mg kg–1) than the synthetic Mh samples (3786–4321 mg kg–1), P desorption exhibited the opposite trend (~14% vs ~8%). The substantial P adsorption capacity of synthetic Mh confirmed the adsorption data for pedogenic clays, which were strongly influenced by magnetic susceptibility, Mh and gibbsite contents, and specific surface area.

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Adsorption of Fluometuron, Prometryne, Sencor, and 2,4-D by Soils

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v57i4.10726 ◽

1969 ◽

Vol 57 (4) ◽

pp. 286-293 ◽

Cited By ~ 2

Author(s):

L. C. Liu ◽

H. R. Cibes-Viadé

Keyword(s):

Organic Matter ◽

Cation Exchange ◽

Adsorption Capacity ◽

Cation Exchange Capacity ◽

Organic Matter Content ◽

Clay Content ◽

Exchange Capacity ◽

Matter Content ◽

The Mean ◽

Highly Correlated

The adsorption capacity of Fluometuron, Prometryne, Sencor, and 2,4-D by 48 local soils was determined spectrophotometrically. The mean adsorptivities of the four herbicides by these soils were as follows: Prometryne 37.0 percent, Sencor 23.0 percent, Fluometuron 22.6 percent, and 2,4-D 12.4 percent. The results indicated that organic matter content was the factor most highly correlated with adsorption of these herbicides by the 48 soils. Cation exchange capacity was found to correlate significantly with adsorption of Fluometuron, Prometryne, and Sencor. Such was not the case with 2,4-D. Correlation between clay content and adsorption of Fluometuron and Sencor was statistically significant. In contrast, no significant correlation was noted between clay content and adsorption of Prometryne and 2,4-D.

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Influence of soil pH on inorganic phosphorus sorption and desorption in a humid brazilian Ultisol

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832005000500004 ◽

2005 ◽

Vol 29 (5) ◽

pp. 685-694 ◽

Cited By ~ 38

Author(s):

Shinjiro Sato ◽

Nicholas Brian Comerford

Keyword(s):

Soil Ph ◽

Ph Value ◽

Tropical Soils ◽

Inorganic Phosphorus ◽

Phosphorus Sorption ◽

Tropical Regions ◽

P Sorption ◽

Phosphorus Desorption ◽

P Desorption ◽

P Bioavailability

Liming is a common practice to raise soil pH and increase phosphorus (P) bioavailability in tropical regions. However, reports on the effect of liming on P sorption and bioavailability are controversial. The process of phosphorus desorption is more important than P sorption for defining P bioavailability. However few studies on the relationship between soil pH and P desorption are available, and even fewer in the tropical soils. The effects of soil pH on P sorption and desorption in an Ultisol from Bahia, Brazil, were investigated in this study. Phosphorus sorption decreased by up to 21 and 34 % with pH increases from 4.7 to 5.9 and 7.0, respectively. Decreasing Langmuir K parameter and decreasing partition coefficients (Kd) with increasing pH supported this trend. Phosphorus desorption was positively affected by increased soil pH by both the total amount of P desorbed and the ratio of desorbed P to initially sorbed P. A decreased K parameter and increased Kd value, particularly at the highest pH value and highest P-addition level, endorsed this phenomenon. Liming the soil had the double effect of reducing P sorption (up to 4.5 kg ha-1 of remaining P in solution) and enhancing P desorption (up to 2.7 kg ha-1 of additionally released P into solution).

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Relationship of soil properties to fractionation, bioavailability and mobility of lead and zinc in soil

Plant Soil and Environment ◽

10.17221/2201-pse ◽

2008 ◽

Vol 53 (No. 5) ◽

pp. 225-238 ◽

Cited By ~ 28

Author(s):

N. Finžgar ◽

P. Tlustoš ◽

D. Leštan

Keyword(s):

Organic Matter ◽

Regression Analysis ◽

Soil Organic Matter ◽

Soil Properties ◽

Multiple Regression ◽

Contaminated Soils ◽

Organic Matter Content ◽

Clay Content ◽

Exchange Capacity ◽

Matter Content

Sequential extractions, metal uptake by Taraxacum officinale, Ruby’s physiologically based extraction test (PBET) and toxicity characteristic leaching procedure (TCLP), were used to assess the risk of Pb and Zn in contaminated soils, and to determine relationships among soil characteristics, heavy metals soil fractionation, bioavailability and leachability. Regression analysis using linear and 2nd order polynomial models indicated relationships between Pb and Zn contamination and soil properties, although of small significance (P < 0.05). Statistically highly significant correlations (P < 0.001) were obtained using multiple regression analysis. A correlation between soil cation exchange capacity (CEC) and soil organic matter and clay content was expected. The proportion of Pb in the PBET intestinal phase correlated with total soil Pb and Pb bound to soil oxides and the organic matter fraction. The leachable Pb, extracted with TCLP, correlated with the Pb bound to carbonates and soil organic matter content (R2 = 69%). No highly significant correlations (P < 0.001) for Zn with soil properties or Zn fractionation were obtained using multiple regression.

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Influence of brick manufacturing on phosphorus and sulfur in different agro-ecological soils of Bangladesh

Bangladesh Journal of Scientific Research ◽

10.3329/bjsr.v29i2.32329 ◽

2017 ◽

Vol 29 (2) ◽

pp. 123-131

Author(s):

Reshma Akter ◽

Md Jamal Uddin ◽

Md Faruque Hossain ◽

Zakia Parveen

Keyword(s):

Organic Matter ◽

Cation Exchange ◽

Soil Ph ◽

Cation Exchange Capacity ◽

Clay Content ◽

Exchange Capacity ◽

Soil Samples ◽

Maximum Accumulation ◽

Brick Kilns ◽

Total P

A study was carried out to evaluate the effects of brick manufacturing on phosphorus (P) and sulfur (S) concentrations in soil and plant collected from different distances of brick kilns in four AEZs of Bangladesh. Forty eight composite soil samples (0 - 15 cm depth) were collected from 48 points in 12 different sites at 0 m, 300 m, 800 m and 1500 m from brick kilns, where most (site 2, site 3, site 5, site 6, site 7, site 9 and site 10) of the brick kilns used coal for brick burning purposes. Plant samples (rice straw and different vegetables) were also collected from the respective fields except 0 m distances. Significantly (p ? 0.05) lower organic matter, cation exchange capacity, clay content and soil pH were found at 0 m distances compared to other distances. Highest concentration of total P in soil were recorded at 0 m distances and these concentrations decreased with increasing distances from the brick kilns in most of the sites; whereas available P is significantly lower at 0 m distances than that of other distances. Total and available concentration of S in soil followed the trend 0 m>300 m>800 m>1500 m. Maximum accumulation of P (69.15 mg kg-1) and S (0.14%) in plant was found at 800 m away from the brick kiln.Bangladesh J. Sci. Res. 29(2): 123-131, December-2016

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Pronamide Phytotoxicity in Ten Wisconsin Soils

Weed Science ◽

10.1017/s0043174500055600 ◽

1980 ◽

Vol 28 (4) ◽

pp. 429-432 ◽

Cited By ~ 5

Author(s):

T. E. Dutt ◽

R. G. Harvey

Keyword(s):

Organic Matter ◽

Chemical Properties ◽

Clay Content ◽

Exchange Capacity ◽

Fresh Weight ◽

Relationship Of ◽

Physical And Chemical ◽

Mg Content ◽

The Relationship ◽

And Chemical Properties

Pronamide [3,5-dichloro-(N-1, 1-dimethyl-2-propynyl) benzamide] phytotoxicity was compared in 10 Wisconsin soils and the relationship of activity to soil physical and chemical properties appraised. Twelve soil properties were measured and correlated with pronamide I50(50% fresh weight inhibition) values using oats (Avena sativaL. ‘Portal’) as the indicator plant in bioassays conducted under greenhouse conditions. Organic matter was the soil variable most inversely correlated with pronamide phytotoxicity. Cation exchange capacity, field moisture capacity, and Mg content were also inversely correlated with pronamide phytotoxicity, but probably reflect changes in soil organic matter levels. Clay content did not significantly affect pronamide phytotoxicity.

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Development of a composite soil degradation assessment index for cocoa agroecosystems in southwestern Nigeria

Solid Earth ◽

10.5194/se-8-827-2017 ◽

2017 ◽

Vol 8 (4) ◽

pp. 827-843 ◽

Cited By ~ 3

Author(s):

Sunday Adenrele Adeniyi ◽

Willem Petrus de Clercq ◽

Adriaan van Niekerk

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Properties ◽

Cation Exchange ◽

Cation Exchange Capacity ◽

Soil Degradation ◽

Clay Content ◽

Exchange Capacity ◽

Southwestern Nigeria ◽

Assessment Index

Abstract. Cocoa agroecosystems are a major land-use type in the tropical rainforest belt of West Africa, reportedly associated with several ecological changes, including soil degradation. This study aims to develop a composite soil degradation assessment index (CSDI) for determining the degradation level of cocoa soils under smallholder agroecosystems of southwestern Nigeria. Plots where natural forests have been converted to cocoa agroecosystems of ages 1–10, 11–40, and 41–80 years, respectively representing young cocoa plantations (YCPs), mature cocoa plantations (MCPs), and senescent cocoa plantations (SCPs), were identified to represent the biological cycle of the cocoa tree. Soil samples were collected at a depth of 0 to 20 cm in each plot and analysed in terms of their physical, chemical, and biological properties. Factor analysis of soil data revealed four major interacting soil degradation processes: decline in soil nutrients, loss of soil organic matter, increase in soil acidity, and the breakdown of soil textural characteristics over time. These processes were represented by eight soil properties (extractable zinc, silt, soil organic matter (SOM), cation exchange capacity (CEC), available phosphorus, total porosity, pH, and clay content). These soil properties were subjected to forward stepwise discriminant analysis (STEPDA), and the result showed that four soil properties (extractable zinc, cation exchange capacity, SOM, and clay content) are the most useful in separating the studied soils into YCP, MCP, and SCP. In this way, we have sufficiently eliminated redundancy in the final selection of soil degradation indicators. Based on these four soil parameters, a CSDI was developed and used to classify selected cocoa soils into three different classes of degradation. The results revealed that 65 % of the selected cocoa farms are moderately degraded, while 18 % have a high degradation status. The numerical value of the CSDI as an objective index of soil degradation under cocoa agroecosystems was statistically validated. The results of this study reveal that soil management should promote activities that help to increase organic matter and reduce Zn deficiency over the cocoa growth cycle. Finally, the newly developed CSDI can provide an early warning of soil degradation processes and help farmers and extension officers to implement rehabilitation practices on degraded cocoa soils.

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Phosphorus sorption on tropical soils with relevance to Earth system model needs

Soil Research ◽

10.1071/sr18197 ◽

2019 ◽

Vol 57 (1) ◽

pp. 17 ◽

Cited By ~ 2

Author(s):

Julia Brenner ◽

Wesley Porter ◽

Jana R. Phillips ◽

Joanne Childs ◽

Xiaojuan Yang ◽

...

Keyword(s):

Sorption Isotherms ◽

Clay Content ◽

Tropical Soils ◽

Soil Characteristics ◽

P Availability ◽

Earth System ◽

Phosphorus Sorption ◽

Soil P ◽

P Sorption ◽

Earth System Models

Phosphorus (P) availability critically limits the productivity of tropical forests growing on highly weathered, low-P soils. Although efforts to incorporate P into Earth system models (ESMs) provide an opportunity to better estimate tropical forest response to climate change, P sorption dynamics and controls on soil P availability are not well constrained. Here, we measured P and dissolved organic carbon (DOC) sorption isotherms on 23 soils from tropical Oxisol, Ultisol, Inceptisol, Andisol, and Aridisol soils using P concentrations from 10 to 500mg P L−1, and DOC concentrations from 10 to 100mg DOC L−1. Isotherms were fit to the Langmuir equation and parameters were related to soil characteristics. Maximum P sorption capacity (Qmax) was significantly correlated with clay content (ρ=0.658) and aluminium (Al)- or iron (Fe)-oxide concentrations (ρ=0.470 and 0.461 respectively), and the DOC Qmax was correlated with Fe oxides (ρ=0.491). Readily available soil characteristics could eventually be used to estimate Qmax values. Analysis of literature values demonstrated that the maximum initial P concentration added to soils had a significant impact on the resultant Qmax, suggesting that an insufficiently low initial P range could underestimate Qmax. This study improves methods for measuring P Qmax and estimating Qmax in the absence of isotherm analyses and provides key data for use in ESMs.

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Sorption and Desorption of Tembotrione and its Metabolite AE 1417268 in Soils with Different Attributes

Planta Daninha ◽

10.1590/s0100-83582019370100096 ◽

2019 ◽

Vol 37 ◽

Cited By ~ 2

Author(s):

A.T. FARIA ◽

C.A. FIALHO ◽

M.F. SOUZA ◽

N.M. FREITAS ◽

A.A. SILVA

Keyword(s):

Organic Matter ◽

High Performance ◽

Organic Matter Content ◽

Clay Content ◽

Tropical Soils ◽

Matter Content ◽

Direct Relation ◽

Carryover Effects ◽

Physical Attributes ◽

Low Levels

ABSTRACT: Tembotrione is registered in Brazil for maize and is used in large areas of the country in each harvest. In recent years, producers have reported carryover effects of this herbicide in succeeding crops to maize. This fact can be attributed to tembotrione recommendations without knowing their interactions with tropical soils colloids. In this study, using high-performance liquid chromatography, it was possible to evaluate the influence of chemical and physical attributes on the sorption and desorption of tembotrione, as well as its metabolite AE 1417268, on seven soils from different regions of Brazil. The coefficients referring to sorption and desorption, as well as the hysteresis index (Kf, 1/n and H) of tembotrione and its metabolite were influenced by pH, clay content and organic matter. In soil samples with low levels of clay and organic matter, values of sorption coefficients were reduced as pH increased. The desorption of tembotrione and its metabolite in all soils were low, mainly in the clayey ones and in soils with higher organic matter content. The sorption of tembotrione and its metabolites varies with the attributes of soil, presenting a direct relation with clay and organic matter contents and an inverse one with soil pH. The desorption of tembotrione and its metabolite decreased with the increase in clay and organic matter contents in the evaluated soils.

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Evaluation of the lime requirement of tropical soils in terms of other soil characteristics

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v36i2.12795 ◽

1969 ◽

Vol 36 (2) ◽

pp. 155-160

Author(s):

M. A. Lugo López ◽

F. Abruña ◽

J. Roldán

Keyword(s):

Cation Exchange ◽

Clay Mineral ◽

Cation Exchange Capacity ◽

Ph Value ◽

Organic Matter Content ◽

Clay Content ◽

Tropical Soils ◽

Exchange Capacity ◽

Matter Content ◽

Significant Regression

The quantity of limestone required to bring the pH of various acid Puerto Rican soils to 6.5 was investigated and found to vary from several hundred to several thousands pounds per acre. To investigate the relation of clay-mineral type, clay content, cation-exchange capacity, organic-matter content, and pH to lime requirement, these properties were determined for several soils. A highly significant regression of lime requirement on pH was obtained which can be expressed by the equation: Y = 18.39 — 3.196 X, where Y is the lime requirement and X is the pH value. Multiple regressions including other factors did not significantly increase the variability which could be explained on terms of the first regression. Further analysis were made by arranging the data according to the predominant clay mineral. For kaolinitic soils highly significant correlations were obtained between lime requirement and either pH or cation exchange capacity. The regressions were: (a) Y = 15.26 — 2.632 pH, and (b) Y = 3.048 + 0.5774 (cation-exchange capacity), where Y is the lime requirement. A regression of lime requirement on both factors did not significantly increase the variability explained by the second equation. No significant regressions were obtained for beidellitic soils.

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