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1.
Abstract

Quantifying the effects of soil acidity on plant growth remains a challenging research topic as numerous soil and plant growth factors are influenced by pH and lime. In the field, annual ryegrass (Lolium multiflorum Lam. ‘Marshall') responded positively to the application of 3.8 Mg lime/ha on a strongly acid (pH 4.7) Lilbert loamy fine sand (loamy, siliceous, thermic, arenic Plinthic Paleudult) over three growing seasons. Dry matter yield in some cuttings, however, was better correlated with soil Al, P, Ca, Mg, and K than with pH. A greenhouse study was undertaken to quantitatively determine the effects of these five minerals plus Mo on ryegrass yield in limed and unlimed Lilbert soil material. Three ryegrass cuttings were obtained from unlimed (pH 4.8) or limed (1000 mg CaCO3/kg) Lilbert soil which was also amended with five rates of Ca, K, Mg, Al, P, and Mo in combinations stipulated by central composite design methodology. Response surface models that fit yield to the applied treatments and soil test data were complex because all factors and many interactions were significant. Furthermore, the models were transformed as the plants matured and element availability changed due to mineral uptake. Most yield improvement derived from liming occurred as a result of the elimination of exchangeable Al with a concomitant increase in P efficiency. Applied Ca did not alleviate Al toxicity in unlimed soil. Chlorotic plants developed in all pots where Mg was excluded. Yield was increased by applied Mg and Mo in unlimed soil, but not in limed soil. Applied K improved yield only in limed soil. Although regression accounted for a large portion of the yield variability (R2 values ranged from 0.75 to 0.95), these models were unable to accurately predict yield in control treatments.  相似文献   

2.
Abstract

This field study was conducted to evaluate nutrient availability and Coastal bermudagrass [Cynodon dactylon (L.) Pers.] yield response to factorial combinations of applied limestone and P in a strongly acid (pH 4.7), infertile soil. Limestone was applied at rates of 0, 672, and 3808 kg ha‐1 to a Lilbert loamy fine sand (loamy, siliceous, thermic, arenic Plinthic Paleudult). Phosphorus was applied at rates of 0, 30, 60, 90, 120, 240, and 480 kg P ha‐1. Soil pH in the surface 15 cm initially increased to 6.2 in response to the high limestone rate, but subsequently declined due to N fertilization. Lime increased soil test P, Ca, and Mg and decreased K and Al. The efficiency of increasing soil test P with fertilizer P was low, but improved as a consequence of liming. Coastal bermudagrass yield increased by as much as 37 percent from P application. Maximum yield coincided with 10 to 15 mg kg‐1 or greater soil test P and tissue P concentrations that ranged from 1.6 to 2.2 g kg‐1. Lime Increased tissue Ca and Mg, but had no effect on plant P concentrations. Yield was unaffected by lime despite its positive effect on soil P and an apparent K‐Mg antagonism. Plant nutrients obtained from deep rooting of the bermudagrass into an argiilic horizon may have precluded any positive effect of lime on Coastal bermudagrass yield.  相似文献   

3.
Abstract

Tall fescue (Festuca arundinacea) is assuming increasing importance as a pasture species in South Africa. Many of the soils on which fescue is grown are inherently high in exchangeable Al and are characterized by high P‐immobilization capacities. The responses of fescue to dolomitic lime and P were examined in a factorial field trial on a red clay (Kandiustalfic Eustrustox) having a pH(KCl) and acid saturation [100(Al+H)/(Al+H+Ca+Mg+K)] in the unlimed state of 4.1 and 48%, respectively. A significant, though very limited, dry‐matter yield response to lime was evident (yields in the absence of lime were approximately 80% of the yields obtained at high lime levels). This pattern in the response to lime remained consistent over the three seasons of experimentation, despite soil acidity levels being substantially increased through the periodic use of ammonium sulphate as the N source in the trial. A significant response to P was evident at the first harvest after establishment; thereafter, P treatments had no effect on yield. The lime and P response data obtained in this investigation indicate that tall fescue is much more tolerant of soil acidity and has substantially lower soil P requirements than other important crop and pasture species in this country, such as maize (Zea mays) and Italian ryegrass (Lolium multiflorum). Lime significantly increased herbage Mg levels yet, in general, did not influence Ca levels in the herbage. Concentrations of Mg in the herbage exceeded Ca concentrations at all lime rates. Luxury uptake of K resulted in the K/(Ca+Mg) equivalents ratio in the herbage frequently exceeding the tetany hazard threshold of 2.2.  相似文献   

4.
Liming and wood ash application are measures to decrease acidification of forests soils. The assessment of lime requirement can be based on that base saturation, which indicates a low risk of acid toxicity. Because of a wide spread Mg deficiency in Central European forests, Mg containing lime is normally applied. Ash from untreated wood is applied to decrease soil acidity as well as to improve K and P nutrition. In wood ash, K is the most soluble nutrient, follwed by Ca and Mg. The overall dissolution rate of lime applied to the forest floor is about 1t ha?1 a?1. After liming, soil solution alkalinity and Mg concentrations increase markedly, while changes of Ca, H ions and Al concentrations are less pronounced. After the application of wood ash, K concentrations increase due to the high K content and the high solubility of K in wood ash. After the application of a sufficiently high dosage of lime to the forest floor, the decrease of acidity in deeper soil layers may need decades because of the low solubility of lime. Nitrification and nitrate leaching induced by lime or wood ash may reduce their acid buffering efficiency.  相似文献   

5.
Soybean is one of the most important legume crops in the world. Two greenhouse experiments were conducted to determine the influence of liming and gypsum application on yield and yield components of soybean and changes in soil chemical properties of an Oxisol. Lime rates used were 0, 0.71, 1.42, 2.14, 2.85, and 4.28 g kg?1 soil. Gypsum rates applied were 0, 0.28, 0.57, 1.14, 1.71, and 2.28 g kg?1 soil. Lime as well as gypsum significantly increased grain yield in a quadratic fashion. Maximum grain yield was achieved with the application of 1.57 g lime per kg soil, whereas the gypsum requirement for maximum grain yield was 1.43 g per kg of soil. Lime significantly improved soil pH, exchangeable soil calcium (Ca) and magnesium (Mg) contents, base saturation, and effective cation exchange capacity (ECEC). However, lime application significantly decreased total acidity [hydrogen (H) + aluminum (Al)], zinc (Zn), and iron (Fe) contents of the soil. The decrease in these soil properties was associated with increase in soil pH. Gypsum application significantly increased exchangeable soil Ca, base saturation, and ECEC. However, gypsum did not change pH and total acidity (H + Al) significantly. Adequate soil acidity indices established for maximum grain yield with the application of lime were pH 5.5, Ca 1.8 cmolc kg?1, Mg 0.66 cmolc kg?1, base saturation 53%, Ca saturation 35%, and Mg saturation 13%. Soybean plants tolerated acidity (H + Al) up to 2.26 cmolc kg?1 soil. In the case of gypsum, maximum grain yield was obtained at exchangeable Ca content of 2.12 cmolc kg?1, base saturation of 56%, and Ca saturation of 41%.  相似文献   

6.
Abstract

Surface liming will prevent the formation of an ‘acid roof’ on the surface of soil cropped in no‐till corn (Zea mays L.). A study was begun in 1985 to determine the effectiveness of unincorporated liming in raising pH in no‐till soil which had developed significant acidity throughout the upper 15 cm. Lime was applied at 0, 3.36, 6.72 and 10.08 Mg ha‐1. All lime was applied on 26 April 1985 and was not incorporated. The pre‐liming pH at 0‐5 cm below the surface was 4.5; after two months the pH was raised to 5.6, 5.8, and 6.0 by 3.36, 6.72 and 10.08 Mg ha‐1 of lime, respectively. After 19 months soil‐pH was raised to 6.0, 6.4 and 6.6 by liming at 3.36, 6.72 and 10.08 Mg ha‐1 respectively. Soil‐pH below 5 cm was not affected by any rate of lime during the first 19 months after liming. Tissue analysis of corn ear leaves indicated that calcium uptake was increased significantly by lime in 1985, while manganese uptake was significantly reduced. In 1986, increases in calcium were greater than in 1985 and addtional significant reduction in manganese uptake was accompanied by significantly reduced zinc and copper uptake. In both 1985 and 1986, a trend toward lower average corn grain yield in unlimed plots than in limed plots was noted, but the yield increases due to lime were not statistically significant in either year. This study will be continued as a long term investigation of lime penetration into no‐till soil and response of corn to soil‐pH changes.  相似文献   

7.
Mineral element deficiencies and toxicities are common problems associated with sorghum [Sorghum bicolor (L.) Moench] production on acid soils. To better understand some of the mineral element problems and the analysis of plant tissue of sorghum plants grown on acid soils, four sorghum genotypes were grown on an acid Oxisol at Carimagua, Colombia limed with dolomite at 2 and 6 Mg ha‐1.

Samples for mineral element analyses were obtained from leaves at different positions on the four genotypes. Concentrations of P and Mg were highest in the flag leaf (Leaf No. 1) and decreased as the position on the plant declined from the top of the plant for plants grown at 2 Mg lime ha‐1. Similar decreases in P, Mg, K, and Zn concentrations occurred in plants grown with 6 Mg lime ha‐1. Concentrations of Ca, S, Si, Mn, Fe, Cu, and Al increased as leaf position declined from the flag leaf for plants grown at 2 and 6 Mg lime ha‐1. The higher lime supply enhanced Ca and reduced Mn and Fe concentrations in leaves. Differences in mineral element concentrations for the four genotypes used were fairly extensive. The elements to show the greatest range among genotypes were Al and Si and the elements to show the least range among genotypes were P, K, and S. Care should be used in collecting leaf samples for plant analysis and genotypic differences for accumulation of mineral elements should be considered in interpretation of results.  相似文献   

8.
Abstract

The cost and difficulty of applying lime on hilly pastures or small forage fields makes it appropriate to devote attention to efficiency of lime utilization. This study evaluated effects of calcitic and dolomitic lime on yield and mineral composition of 11 forage species grown on soil with a low base status of 0.46 cmolc as Ca and 0.18 cmolc as Mg kg‐1. Both lime types increased dry matter production, but only Lolium multiflorum responded more positively to dolomitic lime. The low Mg level in the soil was not a major factor limiting yield. Increase in yield was mainly attributed to the increase in pH with the concurrent decrease in Al level and to an increased Ca availability to plants. The species ranked as follows according to the magnitude of yield increase due to calcitic liming: Trifolium fragiferum > Trifolium pratense > Vicia sativa > Vicia villosa > Trifolium repens > Lolium perenne > Lolium multiflorum > Festuca arundinaceae = Lolium (multiflorum x perenne x perenne) > Trifolium subterraneum > Dactylis glomerata. The most responsive, Trifolium fragiferum, did not grow without lime. The least responsive, Dactylis glomerata, showed a yield increase of 36%. A similar ranking was obtained when all species were evaluated for Al tolerance using a 48 hour root elongation bioassay. In both unlimed soil and soil limed with calcitic lime, Mg concentrations of all species were relatively low. Although they were generally not low enough to have an effect on yield, they barely met the Mg nutritional requirement of cattle. By adding dolomitic lime, Mg content increased in grasses an average of 3.7 fold and in legumes by 2.4 fold. Grasses were similar in Ca, Mg, and K concentrations within a soil treatment. Legumes showed a greater range with the two vetches having the lowest Ca and Mg concentrations and red clover the highest.  相似文献   

9.
Soybean is an important crop for the Brazilian economy, and soil acidity is one of the main yield-limiting factors in Brazilian Oxisols. A field experiment was conducted during three consecutive years with the objective to determine soybean response to liming grown on Oxisols. Liming rates used were 0, 3, 6, 12, and 18 Mg ha?1. Liming significantly increased grain yield in a quadratic trend. Ninety percent maximum economic grain yield (2900 kg ha?1) was achieved with the application of about 6 Mg lime ha?1. Shoot dry weight, number of pods per plant, and 100-grain weight were also increased significantly in a quadratic fashion with increasing liming rate from 0 to 18 Mg ha?1. These growth and yield components had a significant positive association with grain yield. Maximum contribution in increasing grain yield was of number of pods per plant followed by grain harvest index and shoot dry weight. Uptake of nitrogen (N) was greatest and phosphorus (P) was least among macronutrients in soybean plant. Nutrient-use efficiency (kg grain per kg nutrient accumulation in grain) was maximum for magnesium (Mg) and lowest for N among macronutrients. Application of 3 Mg lime ha?1 neutralized all aluminum ions in soil solution. Optimal acidity indices for 90% of maximum yield were pH 6.0, calcium (Ca) 1.6 cmolc kg?1, Mg 0.9 cmolc kg?1, base saturation 51%, cation exchange capacity (CEC) 4.8 cmolc kg?1, Ca/Mg ratio 1.9, Ca?/?potassium (K) ratio 5.6, and Mg/K ratio 3.0.  相似文献   

10.
Abstract

Since ryegrass (Lolium sp.) is a widely grown cool‐season forage grass, its magnesium concentration is of special interest to ruminant livestock producers. This study was conducted to investigate the effect of calcitic or dolomitic lime addition on dry matter yield and mineral composition of hybrid ryegrass, Lolium (multiflorum x perenne x perenne) grown in eight acidic soils. Each soil received two levels of calcitic or dolomitic lime, L(C1) and L(C2) or L(D1) and L(D2), which raised pH to approximately 5.3, and 6.0. Dry matter yield response was obtained only in soils having an initial % Al saturation ≥59, % Mg saturation ≤10 and % Ca saturation ≤21. Only in one soil, which had an initial exchangeable Mg level of 0.05 cmolc/kg of soil, was response to dolomitic lime higher than that obtained with calcitic lime. Magnesium concentration in dry matter was increased by both levels of dolomitic lime with the increase dependent on the rate used and on the initial level of exchangeable Mg. The average Mg concentration increased from 0.8 to 3.9 g/kg, from 1.6 to 3.6 g/kg, and from 2.6 to 3.9 g/kg, when ryegrass was grown in soils having low, medium, and high initial exchangeable Mg levels, respectively. Mg concentration in the ryegrass tended to be lower in the unlimed soils than when calcitic lime was used, 1.1 vs. 1.4 g/kg, when the soils had low to medium exchangeable Mg levels. The results suggest that if ryegrass is to be grown in acidic soils containing low to medium levels of exchangeable Mg, the use of dolomitic lime is desirable, even if no yield response to applied Mg is expected, to decrease the probability of the Mg deficiency disease, hypomagnesemia, in ruminant animals.  相似文献   

11.
ABSTRACT

The potential for phosphorus (P) movement from poultry-litter amended soils into surface waters heightens the need to manage elevated P concentrations. Amending high P soils with aluminum (Al) rich drinking water treatment residue in a greenhouse study reduced water extractable P levels and induced P deficiency in container grown wheat. Objectives of the current investigation were to determine the effect of water treatment residue on grain yield, leaf and grain mineral nutrient concentrations in corn (Zea mays L.) grown under field conditions and to examine pH, water and Mehlich 3-extractable P, and 0.01 M calcium chloride extractable Al in the amended soils at two sites. Poultry litter was amended with 0, 5.6, and 11.2 Mg ha? 1 of water treatment residual and applied to two sites prior to planting with corn in 1998. Additional rates (16.8 and 33.6 Mg ha? 1) of water treatment residue were applied directly to half of each plot on site I in 1999. Results indicated that water treatment residue application did not adversely affect corn grain yields or alter concentrations of mineral nutrients in leaves and grain. Water and Mehlich 3-extractable P and calcium chloride extractable Al concentrations were unchanged with water treatment residue applications in both years on both sites. Further studies are needed concerning optimal annual dosages and long term loading rates for direct soil application of water treatment residue to reduce soluble phosphorus.  相似文献   

12.
ABSTRACT

A field study was conducted with the objective of determining response of dry bean (Phaseolus vulgaris L.) to liming and copper (Cu) fertilization applied to an Oxisol. The lime rates used were 0, 12, and 24 Mg ha?1 and Cu rates were 0, 2.5, 5, 10, 20, and 40 kg Cu ha?1. Liming significantly increased common bean grain yield. Liming also significantly influenced soil chemical properties in the top (0–10 cm) as well as in the sub (10–20 cm) soil layer in favor of higher bean yield. Application of Cu did not influence yield of bean significantly. Average soil chemical properties across two soil layers (0–10 and 10–20 cm) for maximum bean yield were pH 6.4, calcium (Ca), 4.2 cmolc kg?1, magnesium (Mg) 1.0 cmolc kg?1, H+Al 3.2 cmolc kg?1, acidity saturation 40.4%, cation exchange capacity (CEC) 8.9 cmolc kg?1, base saturation 63.1%, Ca saturation 45.7%, Mg saturation 18.0%, and Potassium (K) saturation 2.9.  相似文献   

13.
The use of alkaline residues from cellulose industry can increase soil fertility and crop productivity, but some of these residues, such as dregs, can also reduce soil physical quality. This study aimed to evaluate the effects of the dregs compared to lime as corrective for soil acidity applied on the surface under no-tillage. The treatments applied, half in 2004 and half in 2006, were: without corrective; dregs rates of 3.25, 6.5 and 13 Mg ha?1 and dolomitic lime rates of 5.25 and 10.5 Mg ha?1. After 5.5 years since the first application, soil chemical and physical attributes were determined, as well as soybean yield in 2010 and bean yield in 2011. Positive effects were observed on the soil chemical attributes with the application of dregs or lime, such as increased pH, calcium content, cation exchange capacity, and base saturation, and decreased the aluminum saturation. However, it was observed increase in sodium content and calcium/magnesium ratio with the application of dregs, however without impairing the soil physical quality. The soybean and bean yield increased in a similar way using dregs or lime. These results indicate the possibility of using dregs as corrective of soil acidity.  相似文献   

14.
In a ten‐year study of potassium (K) and lime application to a Kalmia sandy loam (fine‐loamy, siliceous, thermic Typic Hapludult), a soil high in nonexchangeable K, corn (Zea mays L.) and soybean [Glycine max (L.) Herr.] have not responded to applied K. The objectives of this study were to determine if a high K‐requiring crop such as tomato (Lycocersicon esculentum Mill. cv. Redpak) would respond to KCl fertilizer rate or lime type (dolomitic, calcitic, and mixed) and rate on such a soil. Potassium was applied at 0, 56, and 112 kg K/ha every year for ten years. Lime was applied at 0, 2, and 9 Mg/ha in calcitic, mixed, and dolomitic forms twice in ten years (1970 and 1973). In 1980, the tenth year of the study, tomato fruit was harvested by hand once‐over to simulate machine harvest and divided into four maturity groups by color. Soil pH was higher with dolomitic than calcitic lime. Soil K saturation was not influenced by lime rate or type. Fruit yield and leaf phosphorus (P), calcium (Ca), and magnesium (Mg) concentrations increased with increasing lime rates. Leaf K, manganese (Mn), iron (Fe), boron (B), copper (Cu), zinc (Zn), barium (Ba), strontium (Sr), and aluminum (Al) concentrations decreased with increasing lime rate. Leaf Mn, Ba, and Sr concentrations were lower with dolomitic than with calcitic lime. Lime type had no effect on tomato yield. Wide ranges in basic cation saturation ratios had little effect on yield. Soil K saturation and leaf K, Zn, and Ba concentrations increased with increasing K rate. Soil Ca and leaf Ca, Mg, and Al concentrations decreased with increasing K rate. Applied K had no effect on total yield but onceover marketable yield increased linearly with increasing K rate. Marketable yield increased 14% with an increase in K rate from 0 to 56 kg/ha. Thus, fruit maturity was apparently hastened by K fertilization.  相似文献   

15.
An on-farm field experiment was conducted on an acidic soil to investigate the effects of combined use of lime and deficient nutrients on herbage yield of alfalfa (Medicago sativa L.). Omitting lime and limiting nutrients led to elevated concentrations of aluminium (Al), iron (Fe), and manganese (Mn) in alfalfa leaves and stems and caused severe reductions in herbage yield of alfalfa. Combined use of lime (2 t ha?1) and nutrients [phosphorus (P): 20 kg ha?1, sulfur (S): 20 kg ha?1, zinc (Zn): 4 kg ha?1, and boron (B): 2 kg ha?1] had the maximum increase in groundcover, root biomass, nodulation, leaf retention, leaf-to-stem ratio, herbage yield, crude protein, and nutrient composition of alfalfa. These beneficial effects were due to raised soil pH; improved calcium (Ca), P, S, Zn, and B nutrition; and reduced Al, Mn, and Fe toxicity. Aluminium and all the nutrients except copper (Cu) were more concentrated in alfalfa leaves than stems.

Aluminum concentration was about three times greater in the lower leaves than in upper leaves. Lower leaves also had much greater concentrations of Ca, Mg, K, S, Fe, Mn, Cu, and B compared with upper leaves. In contrast, P and Zn concentrations were greater in the upper leaves than in lower leaves. Results suggest that the combined use of lime and all the limiting nutrients may realize potential beneficial effects of alfalfa on acidic soils where more than one essential nutrient is deficient. This may increase growth potential, nitrogen contributions, and groundcover by alfalfa and reduce soil erosion and runoff.  相似文献   

16.
Abstract

Soil acidity is one of the major yield constraints to crop production in various parts of the world. Quantifying optimum soil acidity indices is an important strategy for achieving maximum economic crop yields on acid soils. Five field experiments were conducted for three consecutive years using dry bean as a test crop on an Oxisol. The lime rates used were 0, 12, and 24 Mg ha?1 for creating a wide range of soil acidity indices in a no‐tillage cropping system. Grain yield of dry bean was significantly increased by improving soil pH, base saturation, calcium (Ca), magnesium (Mg), and potassium (K) saturation and reducing aluminum (Al) saturation. These soil acidity indices were higher in the 0‐ to 10‐cm soil layer than the 10‐ to 20‐cm soil layer for maximum grain yield. Across two soil depths, optimum values for maximum bean yield were pH 6.5, base saturation 67%, Ca saturation 48%, and Mg saturation 19%. Bean yield linearly increased with increasing K saturation in the range of 1.5 to 3% across two soil depths. There was a significant linear decrease in grain yield with increasing Al saturation in the range of 0 to 8% across two soil depths. Optimal values of soil indices for maximum bean yield can be used as a reference for liming and improving yield of bean crop on Oxisols in a no‐tillage cropping system. Yield components, such as pod number, grain per pod, and 100‐grain weight were significantly improved with liming, and bean yield was significantly associated with these yield components.  相似文献   

17.
Soil acidity is the principal limiting factor in crop production in Oxisols, and deficiency of micronutrients has increased in recent years because of intensive cropping. A field experiment was conducted over three consecutive years to assess response of common bean (Phaseolus vulgaris L.) to lime and iron (Fe) applications on an Oxisol in a no-tillage system. Changes in selected soil chemical properties in the soil profile (0- to 10- and 10- to 20-cm depths) with liming were also determined. Lime rates used were 0, 12, and 24 Mg ha–1, and Fe application rates were 0, 50, 100, 150 200, and 400 kg ha–1. Both lime and Fe were applied as broadcast and incorporated in the soil. Grain yields of common bean were significantly increased with the application of lime. Iron application, however, did not influence bean yield. There were significant changes in soil profile (0- to 10-cm and 10- to 20-cm depths) in pH, calcium (Ca2+), magnesium (Mg2+), hydrogen + aluminum (H+ + Al3+), base saturation, acidity saturation, cation exchange capacity (CEC), Ca2+ saturation, Mg2+ saturation, potassium (K+) saturation, and ratios of Ca/Mg, Ca/K, and Mg/K. These soil chemical properties had significant positive association with common bean grain yield. Averaged across two depths and three crops, common bean produced maximum grain yield at pHw 6.3, Ca2+ 3.8 cmolc kg–1, Mg2+ 1.1 cmolc kg–1, 3.5 H+ + Al3+ cmolc kg–1, acidity saturation 41.8%, CEC 7.5 cmolc kg–1, base saturation 57.4%, Ca saturation 45.2%, Mg saturation 14.2%, K saturation 9.1%, Ca/Mg ratio 3.1, Ca/K ratio 22.6, and Mg/K ratio 6.7.  相似文献   

18.
Surface application of agricultural lime and fertilizers in no-till (NT) systems can be inadequate because of the excess time required for slowly soluble lime to improve soil aggregation such that water and nutrients move more rapidly into and down the soil profile. This study used fluidized gas desulfurization (FGD) gypsum as an alternative to lime because of its greater solubility and calcium (Ca) and sulfur (S) contents. Gypsum was applied to NT cotton (Gossypium hirsutum L.) plots at rates of 0, 2.24, 4.48, and 6.72 Mg ha?1 for 3 years. After 1 year, Ca, S, and soil aggregation increased significantly (P ≤ 0.05) while exchangeable aluminum (Al) activities were reduced. These results indicate that FGD gypsum can increase NT cotton yields by increasing infiltration and soil water contents, reducing runoff, ameliorating exchangeable Al problems, and by providing a readily available source of S, a limiting nutrient in many cotton soils.  相似文献   

19.
Most tropical soils have high acidity and low natural fertility. The appropriate application of lime and cattle manure corrects acidity, improves physical and biological properties, increases soil fertility, and reduces the use of chemical and/or synthetic fertilizers by crops, such as soybean, the main agricultural export product of Brazil. This study aimed to assess the effects of the combination of the application of dolomite limestone (0, 5, and 10 Mg ha?1) and cattle manure (0, 40, and 80 Mg ha?1) on grain yield and the chemical properties of an Oxisol (Red Latosol) cultivated with soybean for two consecutive years. The maximum grain yield was obtained with the application of 10 Mg ha?1 of lime and 80 Mg ha?1 of cattle manure. Liming significantly increased pH index, the concentrations of calcium (Ca2+) and exchangeable magnesium (Mg2+), and cation exchange capacity (CEC) of soil and reduced potential acidity (H+ + Al3+), while the application of cattle manure increased pH level; the concentrations of potassium (K+), Ca2+, and exchangeable Mg2+; and CEC of the soil. During the 2 years of assessment, the greatest grain yields were obtained with saturation of K+, Ca2+, and Mg2+ in CEC at the 4.4, 40.4, and 17.5 levels, respectively. The results indicated that the ratios of soil exchangeable Ca/Mg, Ca/K, K/Mg, and K/(Ca+Mg) can be modified to increase the yield of soybean grains.  相似文献   

20.
Abstract

In Oxisols, acidity is the principal limiting factor for crop production. In recent years, because of intensive cropping on these soils, deficiency of micronutrients is increasing. A field experiment was conducted on an Oxisol during three consecutive years to assess the response of common bean (Phaseolus vulgaris L.) under a no‐tillage system to varying rates of lime (0, 12, and 24 Mg ha?1) and boron (0, 2, 4, 8, 12, 16, and 24 kg ha?1) application. Both time and boron (B) were applied as broadcast and incorporated into the soil at the beginning of the study. Changes in selected soil chemical properties in the soil profile (0- to 10‐ and 10- to 20‐cm depths) with liming were also determined. During all three years, gain yields increased significantly with the application of lime. However, B application significantly increased common bean yield in only the first crop. Only lime application significantly affected the soil chemical properties [pH; calcium (Ca2+); magnesium (Mg2+); hydrogen (H+)+ aluminum (Al3+); base saturation; acidity saturation; cation exchange capacity (CEC); percent saturation of Ca2+, Mg2+, and potassium (K+); and ratios of exchangeable Ca/Mg, Ca/K, and Mg/K] at both soil depths (0–10 cm and 10–20 cm). A positive significant association was observed between grain yield and soil chemical properties. Averaged across two depths and three crops, common bean produced maximum grain yield at soil pHw of 6.7, exchangeable (cmolc kg?1) of Ca2+ 4.9, Mg2+ 2.2, H++Al3+ 2.6, acidity saturation of 27.6%, CEC of 4.1 cmolc kg?1, base saturation of 72%, Ca saturation of 53.2%, Mg saturation of 17.6%, K saturation of 2.7%, Ca/Mg ratio of 2.8, Ca/K ratio of 25.7, and Mg/K ratio of 8.6. Soil organic matter did not change significantly with addition of lime.  相似文献   

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