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1.
Forms and Uptake of Manganese in Relation to Soil Taxonomic Orders in Alluvial Soils of Punjab,India
B. D. Sharma O. P. Choudhary J. K. Chanay P. K. Singh 《Communications in Soil Science and Plant Analysis》2016,47(3):313-327
Different forms of manganese (Mn) were investigated, including total, diethylenetriamine penta-acetic acid (DTPA) extractable, soil solution plus exchangeable (Mn), Mn adsorbed onto inorganic sites, Mn bound by organic sites, and Mn adsorbed onto oxide surfaces, from four soil taxonomic orders in northwestern India. The total Mn content was 200–950 mg kg?1, DTPA-extractable Mn content was 0.60–5.80 mg kg?1, soil solution plus exchangeable Mn content was 0.02–0.80 mg kg?1, Mn adsorbed onto inorganic sites was 2.46–90 mg kg?1, and Mc adsorbed onto oxide surfaces was 6.0–225.0 mg kg?1. Irrespective of the different fractions of Mn their content was generally greater in the fine-textured Alfisols and Inceptisols than in coarse-textured Entisols and Aridisols. The proportion of the Mn fractions extracted from the soil was in the order as follows: Adsorbed onto oxide surfaces > adsorbed onto inorganic site > organically bound > DTPA > soil solution + exchangeable. Based on coefficient of correlation, the soil solution plus exchangeable Mn, held onto organic site and oxide surface (amorphous) and DTPA-extractable Mn, increased with increase in organic carbon of the soil. The two forms, adsorbed onto inorganic site (crystalline) and DTPA extractable, along with organic carbon, increased with increase in clay content of the soil. DTPA-Mn and Mn adsorbed onto oxide surfaces and held on organic site decreased with increased with an increase in calcium carbonate and pH. Total Mn was strongly correlated with organic carbon and clay content of soil. Among the forms, Mn held on the organic site, water soluble + exchangeable and adsorbed onto oxide surface were positively correlated with DTPA-extractable Mn. DTPA-extractable Mn seems to be a good index of Mn availability in soils and this form is helpful for correction of Mn deficiency in the soils of the region. The uptake of Mn was greater in fine-textured Inceptisols and Alfisols than in coarse-textured Entisols and Aridisols. Among the different forms only DTPA-extractable Mn was positively correlated with total uptake of Mn. Among soil properties Mn uptake was only significantly affected by pH of the soil. 相似文献
2.
《Communications in Soil Science and Plant Analysis》2012,43(19-20):2857-2874
Abstract Profiles of semi‐arid–zone soils in Punjab, northwest India, were investigated for different forms of zinc (Zn), including total, diethylenetriamine penta‐acetic acid (DTPA)-extractable, soil solution plus exchangeable (Zn), Zn adsorbed onto inorganic sites, Zn bound by organic sites, and Zn adsorbed onto oxide surfaces. Irrespective of the different fractions of Zn present, its content was higher in fine‐textured Alfisols and Inceptisols than in coarse‐textured Entisols. In general, the higher content of Zn was observed in the surface horizon and then decreased in the subsurface horizons. However, none of the forms of Zn exhibited any consistent pattern of distribution. Organic matter and size fractions (clay and silt) had a strong influence on the distribution of different forms of Zn. Based upon the linear coefficient of correlation, the soil solution plus exchangeable Zn, adsorbed onto inorganic sites, and DTPA‐Zn increased with increase in organic carbon but decreased with increase in pH and calcium carbonate content. Total Zn increased with increase in clay and silt content. Among the different forms, Zn bound by organic sites, water soluble plus exchangeable Zn and Zn adsorb onto oxide (amorphous surfaces) were all correlated with DTPA extractable Zn. The uptake of Zn was more in recent floodplain Entisols than very fine textured Alfisols and Inceptisols. Among the different forms soil solution +exchangeable and DTPA‐extractable Zn was positively correlated with total uptake of Zn. 相似文献
3.
《Communications in Soil Science and Plant Analysis》2012,43(17-18):2550-2567
Profiles of arid and semi‐arid zones soils of Punjab, northwestern India, were investigated for different forms of iron (Fe): total Fe, diethylenetriamine penta‐acetic acid (DTPA)–extractable Fe, soil solution plus exchangeable Fe, Fe adsorbed onto inorganic sites and oxide surfaces, and Fe bound by organic sites. Irrespective of the different fractions of Fe present, its content was higher in the fine‐textured Alfisols and Inceptisols than in the coarse‐textured Entisols and Aridisols. Lower content of total Fe was observed in the surface horizon and then increased in the subsurface horizons, whereas no set pattern was observed in Entisols. Also, irrespective of the soil orders, the contents of different forms of Fe were higher in the surface horizon and then decreased by depth. None of the forms of Fe exhibited any consistent pattern of distribution. Organic matter and the content of clay and silt fractions had a strong bearing on the distribution of forms of Fe. Based on a linear coefficient of correlation, the soil solution plus exchangeable Fe adsorbed onto inorganic sites and DTPA‐extractable Fe increased with increase in soil organic carbon but decreased with increase in soil pH and calcium carbonate content. Total Fe increased with increase in cation exchange capacity (CEC) and clay and silt content. The results also revealed that there was equilibrium in different fractions of this element. Among the different Fe forms, Fe bound by organic sites, water‐soluble plus exchangeable Fe, and Fe adsorbed onto oxides (amorphous surfaces) were positively correlated with the DTPA‐extractable Fe. Though some forms are interrelated, none of the forms had any relationship with the total Fe. 相似文献
4.
Javid Ahmad Bhat Biswapati Mandal Gora Chand Hazra 《Communications in Soil Science and Plant Analysis》2017,48(4):395-404
Twenty acid soils of West Bengal, India, representing Alfisols, Entisols and Inceptisols orders, were studied to characterize their acidity in relation to physicochemical properties. Total potential acidity (TPA), pH-dependent acidity (PDA), total acidity (TA), hydrolytic acidity (HA) and exchange acidity (EA) ranged from 2.02–6.90, 1.75–6.05, 1.18–2.75, 0.98–1.90 and 0.06–0.85 cmol(p+) kg?1, respectively. Relative order for all forms of acidity was: Entisols>Alfisols>Inceptisols. Average contribution of EA to TPA and TA was 9.7% and 19.7%, respectively, and that of PDA to TPA was 90.1%. Contribution of electrostatically bound H+ to EA was highest for Inceptisols followed by Entisols>Alfisols, and reverse was true for electrostatically bound aluminum (Al3+). All forms of acidity showed significant positive correlations with organic carbon (C) forms of Al but negative correlations with pH of soil. They also showed significant correlations with each other. Soil pH, organic C and exchangeable Al caused most of the variations in different forms of soil acidity. 相似文献
5.
B. D. Sharma Raj Kumar Bijay Singh M. Sethi 《Archives of Agronomy and Soil Science》2013,59(4):367-377
Salt-affected soils in arid and semi-arid tracts of the Indian Punjab are prone to deficiency of micronutrients. Nine profiles from alluvial terraces, sand dunes and palaeochannels in the southwestern Punjab were investigated for total and diethylenetriamine-penta-acetic acid (DTPA) extractable Zn, Cu, Mn and Fe. Soil physiography exerted significant influence on the spatial distribution of micronutrients. Total contents varied from 20–78 for Zn, 8–32 for Cu, and 88–466 mg kg?1 for Mn and 0.82–2.53% for Fe. DTPA-extractable contents varied from 0.10–0.98 for Zn, 0.14–1.02 for Cu, 0.54–13.02 for Fe and 0.82–9.4 mg kg?1 for Mn. Total contents were higher in fine-textured soil than in coarse-textured soils. Concentration of micronutrients in the surface layer was low and there occurred more accumulation in the Cambic horizon. Organic carbon, pH, clay, silt and calcium carbonate exerted strong influence on the distribution of micronutrients. DTPA extractable Zn, Cu, Mn and Fe increased with increasing organic carbon but decreased with increase in pH and calcium carbonate content. Total micronutrient contents increased with increase in clay, silt and calcium carbonate contents and decreased with increase in sand content. 相似文献
6.
Anjorin Godwin Ajiboye Morolake Omolola Aduloju 《Archives of Agronomy and Soil Science》2013,59(10):1393-1408
Available iron, zinc, copper and manganese were determined in six pedons located in upper slope, middle slope and valley bottom soils derived from Abeokuta geological materials in Nigeria. The soils had an average of 639.8 g kg?1 sand, 241.8 g kg?1 clay and 118.4 g kg?1 silt. The fertility status of the soils was low–medium with a strongly acid–neutral reaction, 1.3–15.1 g kg?1 organic carbon contents, moderate–high exchangeable bases and 1.38 mg kg?1 available phosphorus. Both Fe (122.50 mg kg?1) and Mn (111.40 mg kg?1) occurred at toxic levels, whereas the mean Cu (1.27 mg kg?1) and Zn (2.56 mg kg?1) contents were found to be adequate for most crops grown in the region. There were significant positive correlations among the micronutrients and also between soil pH, organic carbon, particle size fractions and micronutrients. The high levels of Fe and Mn were probably due to the presence of oolitic ironstone in the parent material. 相似文献
7.
《Communications in Soil Science and Plant Analysis》2012,43(3-4):347-361
Abstract The accumulation of heavy metals in plants is related to concentrations andchemical fractions of the metals in soils. Understanding chemical fractions and availabilities of the metals in soils is necessary for management of the soils. In this study, the concentrations of copper (Cu), cadmium (Cd), lead (Pb), and zinc (Zn) in tea leaves were compared with the total and extractable contents of these heavy metals in 32 surface soil samples collected from different tea plantations in Zhejiang province, China. The five chemical fractions (exchangeable, carbonate‐bound, organic matter‐bound, oxides‐bound, and residual forms) of the metals in the soils were characterized. Five different extraction methods were also used to extract soil labile metals. Total heavy metal contents of the soils ranged from 17.0 to 84.0 mgCukg?1, 0.03 to 1.09 mg Cd kg?1, 3.43 to 31.2 mg Pb kg?1, and 31.0 to 132.0 mg Zn kg?1. The concentrations of exchangeable and carbonate‐bound fractions of the metals depended mainly on the pH, and those of organic matter‐bound, oxides‐bound, and residual forms of the metals were clearly controlled by their total concentrations in the soils. Extractable fractions may be preferable to total metal content as a predictor of bioconcentrations of the metals in both old and mature tea leaves. The metals in the tea leaves appeared to be mostly from the exchangeable fractions. The amount of available metals extracted by 0.01 mol L?1 CaCl2, NH4OAc, and DTPA‐TEA is appropriate extractants for the prediction of metals uptake into tea plants. The results indicate that long‐term plantation of tea can cause sol acidification and elevated concentrations of bioavailable heavy metals in the soil and, hence, aggravate the risk of heavy metals to tea plants. 相似文献
8.
《Communications in Soil Science and Plant Analysis》2012,43(22):2949-2958
Reports of sugarcane yield responses to silicon (Si), coupled with mounting evidence that elevated crop Si levels reduce both biotic and abiotic stresses, account for the interest in the Si nutrition of this crop. In terms of managing Si supplies to sugarcane in South Africa, uncertainties exist regarding, first, the reserves of plant-available Si in soils, and second, the reliability of soil-test methods for predicting Si availability. In this study, extractable Si was measured in 112 soils collected from sugarcane-producing fields in South Africa. Soils were selected on the basis of dominant soil types and included Inceptisols, Alfisols, Mollisols, Vertisols, Oxisols, Entisols, and Ultisols, varying widely in chemical properties, texture, and extent of weathering. Extractants employed were 0.01 M calcium chloride (CaCl2) and 0.02 N sulfuric acid (H2SO4). Silicon extracted with 0.02 N H2SO4 ranged from 2 to 293 mg kg?1, whereas with 0.01 M CaCl2 the range was 5 to 123 mg kg?1. With both extractants, extractable Si decreased significantly with decreasing pH, exchangeable calcium (Ca), and total cations. In soils with potassium chloride (KCl)–extractable Al+H levels of greater than 0.5 cmolcL?1, extractable Si levels were consistently low, suggesting that soluble Al is implicated in reducing plant-available Si levels. Extractable Si levels were not related to the Bache and Williams P-sorption indices of soils. In the second part of the investigation, sugarcane leaf Si concentrations from 28 sites were related to soil extractable Si levels. The CaCl2 soil test proved markedly superior to H2SO4 as a predictive test for leaf Si levels. 相似文献
9.
《Communications in Soil Science and Plant Analysis》2012,43(10):1320-1325
A laboratory incubation study was conducted to study the influence of liming on extractable boron (B) in acidic soil. Six soils, three each from the Inceptisols and Alfisols, were incubated for 30 days with combinations of lime and B. The soils were acutely deficient in plant-available B (0.09–0.21 mg kg?1). Only <50 percent of applied B was recovered from the soils in available form. Such recovery was lower in Alfisols than that in Inceptisols due to adsorption of a greater amount of added B with iron (Fe?) and aluminium (Al?) oxides in the former soil group. Required dose of lime showed an increase in availability of native soil B, particularly in Inceptisols (26 percent), and a net decrease in recovery of added B (32.5 percent) as compared to no lime control (41.6 percent). The results thus suggest that liming to acidic soils increases extractable B. 相似文献
10.
Aritra Saha Pabitra K. Mani Gora Chand Hazra Arup Dey Shubhadip Dasgupta 《Journal of plant nutrition》2013,36(16):2091-2102
AbstractCritical values of boron (B) for wheat nutrition in soil and plant were determined through a pot experiment with twenty-one surface soils of Alluvial flood plain and Red-latertic belt comprising three major soil orders (Entisols, Alfisols, Inceptisols) with four levels of boron. Application of boron significantly increased the dry matter yield as well as uptake of B by plants. Critical concentration of hot calcium chloride (CaCl2) extractable B in soil for wheat was found to be 0.53?mg?kg?1. The critical plant B concentration varied with growth stages and values were 7.4?mg?kg?1 at panicle initiation and 4.18?mg?kg?1 at maturity, respectively. The findings of this investigation also recommend the application of 2?kg?B?1?ha?1 for ensuring B sufficiency to wheat in Indo-gangetic alluvial and Red-Lateritic soils. 相似文献
11.
《Communications in Soil Science and Plant Analysis》2012,43(19):2391-2401
Copper (Cu) is an essential trace element for all living organisms; however, excess amounts in soil, plants, and food have negative impacts on the environment and human health. The aim of this study was to determine Cu levels in different chemical phases of soils and the relationship between Cu levels in soil phases and concentrations in plants. Soils and plants grown in these soils from an industrialized area in Turkey were analyzed using a selective and four-stage sequential extraction procedure. Copper levels in exchangeable fractions were found up to 658 mg kg?1 while total levels were in the range of 133–5609 mg kg?1. Copper concentrations in plant parts (roots and stem) were in the range of 2.6–240 mg kg?1. The exchangeable forms of Cu were in the range of 3–22% of total Cu concentrations. The relationships were observed between soil Cu and Rumex plant Cu, and soil Cu and root of Brassicasea plant Cu. 相似文献
12.
G. Egiarte G. Corti M. Pinto J. Arostegui F. Macías E. Ruíz-Romero M. Camps Arbestain 《Water, air, and soil pollution》2009,198(1-4):133-148
The objective of this study was to investigate the changes in the chemical partitioning of Cu, Pb, Cr and Zn within a column of soil incubated with an anaerobic sewage sludge (ANSS) for 2.5 months. The soil was irrigated during the incubation period. A sequential extraction method was used to fractionate these metals into exchangeable, weakly adsorbed, organic, Al oxide, Fe–Mn oxide, and residual, respectively. ANSS was applied at a loading rate of 69 Mg ha?1. The soil is a Dystric Cambisol with low pH (<3.8), low CEC [<10 cmol(+) kg?1 below the first 4 cm depth], and low base saturation (<7%). The addition of the ANSS caused a decrease in concentrations of Cu, Pb, and Cr in the A1 horizon, and an increase in the concentrations with depth. Below the A1 horizon, concentrations of Cu increased uniformly (~1 mg cm?1), and the greatest increases were observed in the residual, Fe–Mn oxides, and weakly adsorbed fractions. Maximum increases in Pb occurred at 4–9 cm of depth (1.6 mg cm?1), and mainly affected the weakly adsorbed fraction. Chromium essentially accumulated at the limit between the A2 and the Bw horizons (1.1–1.5 mg cm?1) as residual and organic bound forms, probably through particulate transport. Zinc mainly accumulated in the A1 horizon (2.9 mg cm?1) as exchangeable Zn. At depth, Zn increments were predominantly observed in the residual fraction. The results of this study thus demonstrate the redistribution of contaminants into different chemical pools and soil layers after sludge amendment. 相似文献
13.
Anjorin Godwin Ajiboye Adeleke Joseph Ogunwale 《Archives of Agronomy and Soil Science》2013,59(2):247-258
The potassium status of soils developed over talc overburden in a southern Guinea savanna of Nigeria was evaluated using exchangeable, acid extractable, total and residual potassium values in particle-size fractions. Soil samples collected from genetic horizons of six profile pits at Kampe Forest Reserve were separated into sand, silt and clay fractions. Exchangeable K, acid-extractable K, total K and residual K were determined in these fractions. Reserved K values were similar to those of mobile K, but lower than total and residual K, whereas exchangeable K showed the lowest values. Total K was >25 cmol kg?1 in all the profiles; reserved K ranged from 9.26 to 24.45 cmol kg?1 and mobile K ranged from 5.12 to 29.57 cmol kg?1. Exchangeable K accounted for <1% of total K and ranged from 0.20 to 0.50 cmol kg?1. In most cases, the clay fraction of the soils had the highest values for all potassium forms, followed by the silt fraction, while the sand fraction had the lowest values for these forms of potassium. 相似文献
14.
《Communications in Soil Science and Plant Analysis》2012,43(9-10):1221-1242
Abstract Soils collected from 15 locations from SE Nigeria at the 0‐ to 20‐cm depth were studied for the nutrient elements of fine fractions and their role in the stability of the soils. The objective was to understand the role of these elements in the stability of the aggregates. The fine fractions were clay and silt, and elements measured in the fine fractions were exchangeable sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), exchangeable acidity (EA), cation exchange capacity (CEC), and available phosphorus (P). The aggregate stability was measured at the microlevel with clay dispersible indices and water‐stable aggregate (WSA) <0.25 mm, and at macrolevel with other WSA indices and mean‐weight diameter (MWD). Soils varied from loamy sand to sandy clay. There were more exchangeable cations, CEC, EA, and available P in clay than in the silt fraction. Whereas EA values ranged from 2.8 to 10.4 cmol kg?1, they were between 1.6 and 9.2 cmol kg?1 in silt. The CEC in the clay fraction was from 7.4 to 70 cmol kg?1 and between 4.0 and 32.8 cmol kg?1 in the silt fraction. The WDC were from 50 to 310 g kg?1 while the average dispersion ratio (DR) was generally higher than the corresponding clay‐dispersion ratio (CDR), and the MWD ranged from 0.45 to 2.68 mm. Soils with WSA skewed mostly to higher WSA (>2–1.00 mm) had a higher MWD. Exchangeable Ca2+ in clay correlated significantly with CDR and WSA sizes 1.0–0.5 mm and 0.5–0.25 mm (r=0.45,* 0.51,* and 0.60*), respectively, but negatively correlated with clay flocculation index (CFI) (r=?0.45*). Also, available P in clay correlated respectively with CDR and CFI (r=0.45*, ?0.45*), whereas K+ in silt correlated significantly with WDSi (r=0.64*), CFI (r=0.62*), and CDR (r=?0.65*). Principal component analysis revealed that elemental contents in the silt fraction can play very significant roles in the microaggregate stability. 相似文献
15.
Hoang Huu Chien Maho Tokuda Dang Van Minh Yumei Kang Kozo Iwasaki Sota Tanaka 《Soil Science and Plant Nutrition》2019,65(1):73-81
This study investigated general physicochemical properties of tea garden soils at the alluvial plain of Cong River in Tan Cuong commune, Vietnam. Four gardens were selected as study sites on three transect lines established perpendicularly to the river. Soil samples were collected from the surface (0–10 cm) and subsurface (20–30 cm). Soil texture classes varied from sandy loam to light clay, which was affected by different terrains along the transect lines as well as severe disturbance such as terracing and earth excavation. The levels of total C and total N were correlated with increasing garden age, suggesting the replenishment of soil organic matter pool by the addition of plant residue and manure. Meanwhile, the soils showed strongly acidic nature with the average pH(H2O) of 3.7 at the surface and 3.9 at the subsurface. The effective cation exchange capacity (ECEC) was low at 4.7 and 4.9 cmolc kg?1, respectively, and dominated by exchangeable Al3+. Soil acidification was exacerbated with increasing garden age. However, a relatively large saturation of exchangeable calcium (Ca2+), potassium (K+), and magnesium (Mg2+) on the ECEC was found in the surface soils. The levels of available P were high, occasionally exceeding 1000 and 500 mg kg?1 at the surface and subsurface, respectively. In spite of strongly acidic condition, ammonium (NH4-N) applied as fertilizer was converted to nitrate (NO3-N) to move down to deeper layers. The levels of the bases, P, and mineral N seem to be principally determined by management practices. Significant portion of these nutrients was likely to exist in water soluble forms without adsorption onto soils. It should be required to develop proper schemes and to educate the owners for adequate fertilizer managements. 相似文献
16.
ABSTRACT Orchard efficiency (OE) is one of the indices of evaluating the sustainability in production behavior of citrus orchards. A wide range of soil properties broadly categorized into particle size distribution, water soluble and exchangeable cations, and soil available nutrients were investigated in relation to efficiency of Nagpur mandarin (Citrus reticulata Blanco) orchards established on smectite rich three soil orders (Entisols, Inceptisols, and Vertisols) representing 18 locations of central India. The soil properties, viz., free calcium carbonate (CaCO3), clay content, water soluble- and exchangeable-calcium (Ca2 +), available nitrogen (N), phosphorus (P), and zinc (Zn) contributed significantly towards variation in OE. The threshold limit of these limiting soil properties was further established using multivariate quadratic regression models as: 132.1 g kg? 1 free CaCO3, 418.1 g kg? 1 clay, 149.9 mg L? 1 water soluble Ca2 +, 25.9 cmol(p+) kg? 1 exchangeable Ca2 +, 114.6 mg kg? 1 available N, 12.8 mg kg? 1 available P, and 0.96 mg kg? 1 available Zn in relation to optimum OE of 82.1%. These reference values were very close to those obtained from best fit models, and could be effectively utilized in addressing soil related production constraints for precision-aided citriculture. 相似文献
17.
《Communications in Soil Science and Plant Analysis》2012,43(13-14):1963-1978
Abstract: The fraction distributions of heavy metals have attracted more attention because of the relationship between the toxicity and their speciation. Heavy‐metal fraction distributions in soil contaminated with mine tailings (soil A) and in soil irrigated with mine wastewater (soil B), before and after treatment with disodium ethylenediaminetetraacetic acid (EDTA), were analyzed with Tessier's sequential extraction procedures. The total contents of lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) exceeded the maximum permissible levels by 5.1, 33.3, 3.1, and 8.0 times in soil A and by 2.6, 12.0, 0.2, and 1.9 times in soil B, respectively. The results showed that both soils had high levels of heavy‐metal pollution. Although the fractions were found in different distribution before extraction, the residual fraction was found to be the predominant fraction of the four heavy metals. There was a small amount of exchangeable fraction of heavy metals in both contaminated soils. Furthermore, in this study, the extraction efficiencies of Pb, Cd, and Cu were higher than those of Zn. After extraction, the concentrations of exchangeable Pb, Cd, Cu, and Zn increased 84.7 mg·kg?1, 0.3 mg·kg?1, 4.1 mg·kg?1, and 39.9 mg·kg?1 in soil A and 48.7 mg·kg?1, 0.6 mg·kg?1, 2.7 mg·kg?1, and 44.1 mg·kg?1 in soil B, respectively. The concentrations of carbonate, iron and manganese oxides, organic matter, and residue of heavy metals decreased. This implies that EDTA increased metal mobility and bioavailability and may lead to groundwater contamination. 相似文献
18.
《Communications in Soil Science and Plant Analysis》2012,43(16):2079-2094
A pot experiment was conducted to study the influence of liming on changes in different forms of acidity in relation to soil properties. Thirty-six surface (0–15 cm deep) soil samples were collected from different soil orders, namely Entisols, Inceptisols, Alfisols, and Entisols of coastal saline zone of West Bengal, India, and incubated for 21 days with three doses of lime [i.e., no lime (L0), half lime (L1/2), and full lime (L1)]. Results of analysis of soil showed that there were significant increases in pH in water (pHw) and pH in 0.02 M calcium chloride (CaCl2) (pHCa) (1.3 and 1.5 units) and decrease in total acidity, hydrolytic acidity, exchange acidity, electrostatically bound aluminium (EBAl3+), and electrostatically bound hydrogen (EBH+) upon liming being from 1.53 to 0.57, 1.40 to 0.54, 0.13 to 0.03, 0.08 to 0.01, and 0.06 to 0.02 cmol (p+) kg?1, respectively. The decrease in values of all the forms of acidity was greater in L1 than in L1/2 treatment under Entisols of the terai zone, followed by Entisols of coastal saline zone, Inceptisols, and Alfisols. The forms of acidity showed significant positive correlation with each other but negative correlation with pHw and pHCa, except for EBH+. 相似文献
19.
《Communications in Soil Science and Plant Analysis》2012,43(3):277-289
Sulfur (S) availability in soils of agriculturally cultivated locations in the intermediate midhill zone of the Jammu region of India is a major concern. The total S content ranged between 193 and 774 mg kg?1. The organic S and nonsulfate S were relatively higher and contributed on average 49.05 and 46.71% of total S, respectively. Inorganic sulfate S contributed least to the total S (0.93 to 11.98%), water‐soluble S from 2.21 to 14.82%, and adsorbed S from 7.15 to 50.26%. All the forms of S except adsorbed S correlated positively and significantly with organic carbon content of soils. The multiple regression analysis revealed that the organic carbon content had greater impact on different S forms followed by clay content. Among different forms of S, total S was correlated positively and significantly with organic S (r = 0.983??) and nonsulfate S (r = 0.980??). 相似文献
20.
《Communications in Soil Science and Plant Analysis》2012,43(7-8):1031-1042
Abstract Copper (Cu) is an important heavy metal to be considered in soil contamination, because high concentrations of copper in soil produce toxic effects and may accumulate in plant tissues. In Australia's oldest sewage irrigation farm, located in Werribee, Victoria, soil in the land filtration area is contaminated by Cu. However, Cu content in herbage tissues is in the normal range and has been trending downward since 1979. Therefore, studies on the sorption capacity and sequential extraction of Cu in soil at the Werribee Farm is of significance, not only for better understanding the mechanism of transport, chemical processes, and plant uptake of Cu, but also in providing information for the practical management of sewage farm soils. Methods of combining sorption isotherms with sequential extraction procedures were adopted, and the results showed that the soil in the land filtration area at Werribee Farm has a high sorption capacity for Cu, and distribution coefficients, Kf of Cu, were 629 L kg?1 in surface soils (0–20 cm) and 335 L kg?1 in subsurface soils (20–40 cm). The sequential extraction fractions demonstrate that exchangeable and carbonate fractions are very low, only comprising 3.49 to 5.49% of total copper. The other fractions are also discussed. This characteristic of Cu in soil is related to the low concentration of Cu in plant tissues. 相似文献