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1.
Abstract

Long‐term no‐tillage has profound effects on soil properties which can affect the availability of plant nutrient elements. The objectives were to study the effects of tillage and lime treatments on soil pH and extractable soil micronutrients where poultry litter was used as a nitrogen (N) source. Surface soil samples were taken in the spring and fall for two years from a long‐term tillage experiment that had been in place for nine years. There were two tillage treatments [conventional (CT) and no‐tillage (NT)] and six lime/ gypsum treatments (control, 8,960 kg gypsum ha‐1 every fourth year, 4,480 kg lime ha‐1 every fourth year, and three treatments of 8,960 kg lime ha‐1 in a four‐year period divided by application times into 1, 2, and 4 treatments per year). Poultry litter was applied each year of the two‐year experiment at a rate of 8.96 Mg ha‐1 on a dry weight basis. The crop was corn (Zea maize L.). Soil samples were analyzed for pH and Mehlich‐1 zinc (Zn), manganese (Mn), and copper (Cu). Soil pH was higher for NT than CT and was higher in the spring than in the fall. Lime rates resulted in soil pH increases, but showed less difference for CT than NT. The three 8,960 kg ha‐1 per four yr treatments caused an interaction in that for CT the pH increased more for 2,240 kg ha‐1each year than for 8,960 kg ha‐1 every fourth year and the opposite was true for NT. Extractable Zn, Mn, and Cu all responded to this interaction being lower for the higher pH plots. Extractable Zn was higher for NT possibly due to high Zn from the poultry litter and non‐incorporation for NT. Extractable Cu was lower for NT as expected from the soil pH, whereas extractable Mn was not affected by tillage. Extractable Zn and Cu both increased over time due to inputs from the poultry litter. Neither extractable Zn nor Mn responded to increasing lime rates, however Cu decreased with increasing lime rate. Extractable Cu was influenced mainly by soil pH differences due to tillage and lime. Extractable Zn was influenced much more by tillage and from inputs by the poultry litter and not as much by pH differences. Extractable Mn was the least responsive to tillage and lime treatments of the three micronutrients studied.  相似文献   

2.
长期施用猪粪对红壤酸度的改良效应   总被引：10，自引：1，他引：9  
龙光强  蒋瑀霁  孙波 《土壤》2012,44(5):727-734
土壤酸化严重限制了我国南方红壤区土壤的农业利用。本研究应用江西鹰潭红壤生态实验站长期猪粪养分淋失试验,分析了不同施肥处理（对照处理：N 0 kg/hm2;低量有机肥：N 150 kg/hm2;高量有机肥：N 600 kg/hm2;高量有机肥+石灰处理：有机肥N 600 kg/hm2 ＋石灰3 000 kg/(hm2·3a)）长期施用对红壤酸度的改良效应。研究结果表明,9年高量有机肥施用中土壤pH值平均每年上升0.085个单位,而低量有机肥施用对土壤pH没有显著影响。有机肥长期施用增加了土壤盐基离子浓度,其中Ca、Mg增加幅度较大,使得长期施肥后土壤盐基以Ca为主,其次是Mg,而K、Na比例较低。长期有机肥施用有效降低了红壤旱地表层土壤交换性酸含量,尤其是对交换性铝含量的降低程度较大,且随施肥量的增加而增大,在施肥4年后可基本消除铝毒。高量施肥基础上的石灰添加进一步提高了土壤pH值,加快了土壤酸度改良。红壤旱地猪粪施用显著提高了玉米产量,达到酸度改良效果的最低猪粪用量为Ca 162 kg/hm2。在施肥初期添加一次石灰,将土壤pH值迅速提高,然后通过有机肥对pH的稳定作用保持和逐步提高土壤pH,可在最短时间、用最少投入消除土壤酸害。  相似文献   

3.
Lime (calcium oxide), animal manure and crop straw soil treatments have been shown to ameliorate soil acidity, yet their effectiveness at concurrently enhancing soil fertility status and improving crop yields is less well understood. In this study, an acidic nutrient deficient red soil (Ferralic Cambisol) received these treatments at various dosage rates (% of DW soil) in pot experiments with maize plants. Lime was applied at four dosage rates (0.05%, 0.10%, 0.15% and 0.20%), pig manure at three rates (0.50%, 1.00% and 1.50%), maize straw or milk vetch at two rates (0.50% and 1.00%) and combinations of lime (0.10% or 0.15%) with maize straw (0.50%) and/or pig manure (0.50%). Soils treated with and without chemical fertilizers were also included as controls. Measurements of soil pH, exchangeable acidity, plant available nutrients and maize shoot biomass were recorded. Maize shoot biomass increased by 4.7–7.6 times under pig manure treatments, 1.1–1.6 times under milk vetch, 0.4–1.5 times under lime and 1.1–6.2 times under combination treatments, compared with the control. Soil pH increased by 0.5–0.9 units under lime, by 0.2–0.4 units under pig manure and by 0.7 pH units under the combination treatment relative to the control. Variance partitioning analysis showed that on an individual basis, soil acidity amelioration (pH, exchangeable H+ and Al3+) or nutrient input (C, N, P, K, Ca, Mg, Zn) explained only 4.3% and 5.6% of improved maize growth, respectively. Whereas, their interaction explained 85.9% of the variation. We also report that the over-application of pig manure could lead to P saturation and negative impacts on aquatic systems in the wider environment. Therefore, we recommend a combination of lime, pig manure and straw provides an optimal solution for addressing soil acidity and limiting P saturation in acid soils.  相似文献   

4.
Abstract

Four liming and Mg materials were compared in a greenhouse experiment with soybeans for their ability to raise soil pH, supply Mg, and their effect on the availability of Mn, Cu, Fe, and Zn. Three materials were added at rates of 0, 1, and 2 times the lime requirement, calcitic lime, dolomitic lime, and Hydra‐Mag (an industrial by‐product containing 20% Mg). Sul‐Po‐Mag was the fourth material added as a plus Mg check at a rate based on an equivalent amount of Mg to that supplied by Hydra‐Mag. Plant growth, plant tissue element content and extractable soil elements were determined after growing the soybeans for 5 weeks. Plants in treatments where no lime/Mg materials were added were very small due possibly to Mg deficiency and Al toxicity. The 1 and 2 times rates of the materials gave about equal growth except that the high Sul‐Po‐Mag rate caused salt injury. Hydra‐Mag increased soil pH more than calcitic lime which increased soil pH more than dolomitic lime. Soil and plant Mg levels were increased more by Hydra‐Mag than dolomitic lime when applied at equivalent rates based on the lime requirement. Dolomitic lime gave very good plant growth indicating that it made adequate amounts of Mg available. Hydra‐Mag reduced plant and extractable soil Zn, Cu, and Fe but no more so than calcitic or dolomitic lime. Hydra‐Mag reduced plant Mn more than for the other limes.  相似文献   

5.
Abstract

Results from 2 pastoral field lime trials showed that liming reduced exchangeable Mg. This effect increased with increasing rate of lime and with time following lime application, and was greatest in the top 0–50 mm depth. Soil solutions, sampled 2 years after liming, showed that solution Mg increased in increasing rate of lime. This effect was greatest in the top 20 mm of soil.

Lime incubation studies indicated that Mg fixation did occur on some of the soil studied, at pH >6.2. However, this did not account for the size of the observed effects of liming on exchangeable Mg in the field or explain the observed effects of liming at pH <6.2.

It is suggested therefore, that the major mechanism by which liming reduces exchangeable Mg, on these soils, is through displacement of exchangeable Mg into solution by the added Ca in lime, and subsequent leaching.

Results from other field trials suggest that liming will decrease exchangeable Mg if the change in pH‐dependent CEC (?ECEC) per unit change in soil pH is <15 me 100 g‐1.  相似文献   

6.
Minimum tillage cropping systems and the use of animal manures on cropland are becoming more prevalent. An experiment was initiated to determine the effects of tillage and lime/gypsum variables on uptake of zinc (Zn), manganese (Mn), and copper (Cu) by corn (Zea mays L.) and to show correlations between plant uptake of these metals and soil pH and Mehlich 1‐extractable soil metals where poultry litter was used as a nitrogen (N) source. Surface soil samples were taken in the spring and fall for two years from a long‐term tillage experiment that had been in place for nine years. There were two tillage treatments [conventional (CT) and no‐tillage (NT)] and six lime/gypsum treatments (control, 8,960 kg gypsum ha‐1 every fourth year, 4,480 kg lime ha‐1 every fourth year, and three treatments of 8,960 kg lime ha‐1 in a four‐year period divided by application times into 1, 2, and 4 treatments). Poultry litter was applied each year of the two‐year experiment at a rate of 8.96 Mg ha‐1 on a dry weight basis. Soil samples were analyzed for pH and Mehlich 1‐extractable Zn, Mn, and Cu, and plant tissue (small plant, ear leaf, stalk, and grain) was analyzed for Zn, Mn, and Cu concentrations. Lime treatments resulted in lower Zn in the small plant and ear leaf for CT, but not for NT. Plant Mn was decreased by lime and gypsum rates for small plant, ear leaf, stalk and grain for both years for CT and NT. Correlations for plant Zn versus soil pH were generally non‐significant, except for one year for ear leaf Zn (R=‐0.413**). Correlations for soil pH and plant tissue Cu were all nonsignificant. Correlations for plant Mn and soil pH were strong with R values over 0.80. Plant Mn response to treatments was found at a pH range of 4.2 to 5.8 for ear leaf and pH 5.2 to 6.2 for stalks. Plant Mn and Zn versus Mehlich 1‐extractable soil Mn and Zn, respectively, were negative. This response was possibly due to oxidation‐reduction and non‐incorporation of the lime for Mn and non‐incorporation of the lime for Zn. Also, the poultry litter was high in Zn (447 mg kg‐1), which could have masked pH effects. It was concluded that soil sampling for plant micronutrients for NT, especially where a waste material high in micronutrients is applied, can give erratic and even erroneous results. However, lime and tillage treatments had a predictable effect on micronutrient uptake as related to soil pH.  相似文献   

7.
Lime in pelletized form is potentially more convenient for farmers than ground limestone, as it can be applied using conventional fertilizer‐spreading equipment. Pelletized lime is intended to maintain an optimum soil pH when applied annually at a rate of 350 kg lime/ha/yr. Interactions between lime and N fertilizer rate were examined by applying 0, 75, 150, 225 and 300 kg N/ha/yr (as calcium ammonium nitrate) in combination with 0, 175, 350 and 525 kg pelletized dolomitic lime/ha/yr over 3 yr to a permanent grassland sward used for silage production in County Down, Northern Ireland. Equal rates of ground lime, from the same source as the pelletized lime, were applied as a comparison. Effects on soil chemical properties, grass dry matter (DM) yield and herbage nutrient removal were examined. Lime maintained or slightly increased the soil pH, particularly in the top 2.5 cm of the profile, but there was no difference in the performance of pelletized lime compared to ground lime in any of the parameters measured. Lime had no significant effect on grass DM yield or grass quality; however, there was a significant (P < 0.05) reduction in yield at the first cut, particularly in year 2, when the highest lime rate (525 kg lime/ha/yr) was applied in the absence of N fertilizer. The dolomitic nature of the lime (11% Mg) resulted in significant (P < 0.001) increases in soil and herbage magnesium levels, and this could be beneficial for reducing the incidence of grass tetany in grazing animals. The P content of the herbage was also significantly higher in plots receiving lime, which suggests that lime may have enhanced the mineralization of P or stimulated root growth.  相似文献   

8.
Soil properties were evaluated after 10 years of continuous non-tilled and conventionally tilled corn (Zea mays L.) production on a Maury silt loam (Typic Paleudalfs) soil, which had been in bluegrass (Poa pratensis L.) for 50 years. On limed and nonlimed plots soil samples from 0, 84, 168 and 336 kg/ha N treatments were taken in the 0–5, 5–15 and 15–30 cm layers for determination of organic C and N, soil pH, and exchangeable Al, Mn, Ca, Mg, K.Tillage treatments had no effect on soil bulk density in the 0–15 cm layer. In the 0–5 cm surface layer, organic C and N were approximately twice as high with no-tillage as with conventional tillage; N fertilizer induced a high level of both organic C and organic N. No-tillage decreased soil pH for unlimed plots as compared to conventional tillage, especially at high N-rates, which produced an increase in exchangeable Al and Mn and a decrease in exchangeable Ca down to the 30 cm depth. When lime was applied, the pH of the surface soil was slightly higher under no-tillage. On treatments receiving lime, exchangeable Al and Mn levels were very low with no significant difference in tillage systems. At low rates of N fertilization the 10-year average corn yield was higher for conventional tillage than for no-tillage, but at high rates of N fertilization it was equal or higher for no-tillage treatments receiving lime. Unlimed no-tillage treatments produced lower yields at all N levels during 1975–1979. Deterioration of soil physical properties was not observed.  相似文献   

9.
白浆土是我国东北地区主要低产土壤之一,土体中白浆层通气透水能力极差,生物酶活性很低,导致土壤表旱表涝严重,旱田作物根系有效土层一般只有20 cm左右。为研究白浆土增施有机肥及石灰对大豆土壤酶活性及大豆产量的影响,设置了4个处理。结果表明3种酶活性均为:常规施肥+有机肥常规施肥+石灰+有机肥常规施肥常规施肥+石灰,说明有机肥的施用增加了土壤酶活性,石灰的施用降低了土壤酶活性;有机肥施用增加了土壤有机质,石灰施用增加土壤pH值,与对照相比,常规施肥+石灰处理大豆增产23.76%;常规施肥+有机肥处理增产28.32%;常规施肥+石灰+有机肥处理增产13.07%。说明有机肥及石灰无论是单独施用或是组合施用均对大豆增产有效。  相似文献   

10.
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   

11.
Decreasing winter pasture productivity in unlimed Ultisols has been associated with increased soil acidity due to fertilizer N application. The susceptibility of cool season grasses to soil acidity and associated infertility factors that result in reduced forage yield are not well understood. This field study was undertaken to evaluate the effects of factorial combinations of limestone and P applications on annual ryegrass (Lolium multiflorum Lam. ‘Marshall') dry matter production and tissue mineral concentrations on a strongly acid (pH 4.7), sandy soil. Limestone was applied to a Lilbert loamy fine sand (loamy, siliceous, thermic, arenic Plinthic Paleudult) at rates of 0, 672, or 3808 kg ha‐1. Phosphorus was applied to split plots at rates of 0, 30, 60, 90, 120, 240, or 480 kg P ha‐1. Over three harvest years, ryegrass yields increased 90 to 750% and 25 to 80% at the highest lime and P rates, respectively. In the second year, yield response to applied P was significantly less at the high lime rate which indicated that liming made soil P more plant available. Lime and applied P increased plant tissue P, Ca, and Mg concentrations. Yield was positively correlated with soil pH, P, Ca, and Mg and negatively related to soil K and Al. Clear relationships between individual soil test levels and leaf mineral concentrations with yield fluctuations could not be established because these variables were inextricably related to the lime and P rates. Nevertheless, excessive soil Al, coupled with inadequate P, Ca, and Mg availability, were indicated as important nutritional factors limiting annual ryegrass growth in unlimed soil.  相似文献   

12.
Abstract

We studied the effects of liming on dry matter production, nutrient composition, and grain yields of wheat in field experiments conducted on two soil types at three locations during the 1976–77 and 1977–78 growing seasons. Lime sources were commercial agricultural lime, finely divided stack dust, and dolomitic limestone (which contained 10.6% Mg). Lime applied at 2,800 kg/ha in the 1976–77 and 10,750 kg/ha in the 1977–78 experiments provided Mg from the dolomite at rates of 300 and 1,140 kg/ha, respectively.

Soil pH was significantly increased by liming, but Mg saturation percentages were significantly greater only at the 1,140 kg/ha rate. Forage dry matter and grain yields were not increased by lime applied at the lower rate, but significant increases were found in dry‐matter production in the late fall and spring samplings of the 1977–78 experiment. Those increases in plant growth and dry matter production were probably due to reductions in the soluble Mn and Al concentrations in the soil. Forage N and P concentrations were generally not influenced by liming. Potassium concentrations in forage from the limed plots were usually equal to or greater than those in forage from unlimed plots. Calcitic limestone sources generally increased forage Ca concentrations, but liming with dolomite more often than not depressed Ca concentrations below levels found in the check plots. Dolomite, when applied at the 1,140 kg/ha rate, effectively increased the forage Mg concentration, although the concentration exceeded 0.2% only during the early growth stages. Liming generally showed no significant reduction in the tetany potential of the wheat forage as predicted by the equivalent ratio K/(Ca + Mg).  相似文献   

13.
Abstract

Six legume species and several varieties within the species were grown in a greenhouse pot experiment using the Bt horizon of a Lily (Typic Hapludult) soil. Lime treatments were 0 and 2.2 g Ca(OH)2/kg soil. Liming increased the soil pH from 4.6 to 6.2. The species and varieties responded differentially to lime. Both shoot and root growth of legumes showed a significant species and lime interaction effect. Based on tolerance index groups for shoot growth, alfalfa varieties were classified as very sensitive, red clovers and white clovers as sensitive and Essex soybean and Carroll birdsfoot trefoil as tolerant to the acid soil. The remaining legumes were grouped as moderately tolerant to the acid soil. Liming increased shoot concentrations of Ca in all the legumes and reduced concentration of Mg, K, and Zn. Species and varieties within species differed significantly in concentrations of all mineral elements studied except Mg. Further significant differences in elemental composition were observed due to both lime and lime species interactions. In the limed soil, the Ca concentration of the shoots increased as the tolerance index decreased.  相似文献   

14.
Abstract

Whether a tropical soil should be limed or not for a particular crop is strongly dependent on the levels of soil aluminum (Al) which can be determined with soil tests. Soil pH is used to predict whether lime is needed in less‐weathered soils, although some evidence indicates a soil Al test would be more accurate. The objectives of this study were to determine and to compare the accuracies of four soil tests to separate soils requiring lime from those that do not, and to determine the cause of acid‐soil injury to soybean [Glycine max (L.) Merr.]. Soybean was grown in the greenhouse on four surface soils representing the major land resource areas of Louisiana and were amended with eight rates of lime, yields determined, and soils analyzed for soil pH, extractable Al, CaCl2‐extractable Al, CaCl2‐extractable manganese (Mn), and Al saturation. Acid‐soil injury in soybean grown on the Litro clay and Stough fsl was probably caused by soil‐Al effects while low soil calcium (Ca) and high soil Mn was likely responsible for lower yields from the Mahan fsl. Leaf Ca from the limed Mahan‐soil treatment was 5‐fold greater and leaf‐Mn 7‐fold less than control levels. Regression analyses’ R2 values were similar for all soil tests except for CaCl2‐extractable Mn, which was lower. Soil tests were compared across soil type by selecting treatments that had the same 85% relative yield. Using this data subset, there was no difference in the soil pH among the four soils, while there were significant differences among soils for all other soil test measurements indicating the superiority of soil pH for identifying acid‐soil injury. Critical test values were 5.1 soil pH, 30 mg kg‐1 extractable Al, 7% Al saturation, 0.7 mg‐kg‐1 CaCl2‐extractable Al, and 9 mg‐kg‐1 CaCl2‐extractable Mn.  相似文献   

15.
Abstract

A pot experiment was performed during the 1992 growing season on an acid, sandy topsoil taken from a Swedish liming experiment. A central composite experimental design was used in order to study the effects of supply of phosphorus (P) and micronutrients at different liming levels on yield of barley (Hordeum vulgare L. c.v. Golf), mineral content in plant, straw, and grain, and level of soil extractable nutrients. The results showed no increase of yield due to liming despite the fact that lime increased the yield significantly in the field experiment. The soil appeared initially to have a good balance between the nutrients included in the experimental design with the exception of P. An excessive supply of manganese (Mn) decreased the yield. The contents of calcium (Ca) and aluminum (Al) in the plant were hardly affected by the treatments, while the contents of P, Mn, copper (Cu), and zinc (Zn) more than doubled compared to no supply. The contents of P, Cu, and Zn were mainly influenced by the supply of the actual element, while the content of Mn was more closely related to the supply of lime. Soil pH(H20) and CaCl2‐extractable P, Mn, Cu, and Zn were highly related to the supplies of lime, P, Mn, Cu and Zn, respectively. Only a few interactions were observed.  相似文献   

16.
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   

17.
Abstract

Lime induced depression of exchangeable Mg had been observed previously and it was postulated that yield decreases, which frequently occur at high pH levels may in some instances be due to Mg deficiency. This study was conducted to evaluate the influence of pH on exchangeable Mg in a wide range of acid soils and to determine the effects on recovery of Mg by corn (Zea mays L.) in the greenhouse. Treatments consisted of five pH levels, three P levels, and three Mg levels. Soil Mg was extracted with two neutral salt solutions and double acid. Salt extractable Mg decreased markedly at near neutral pH values, but double acid extractable Mg remained essentially unchanged. In several of the soils where yields were depressed at the highest pH levels, plant Mg content was also significantly lower. However, yield depressions were not ameliorated by Mg applications and could not be ascribed to induced Mg deficiency. Decreased plant uptake of Mg at both low and high pH levels was considered to have resulted from competitive effects between Mg and Al. The evidence suggested that salt extractable Mg did not accurately reflect plant availability.

Because soil reaction has profound effects on the availability of aluminum and many elements essential to plants, liming should be practiced primarily to optimize the utilization of the nutrient resources of soil. While pH values near neutrality are regarded as optimal in many areas of the world, particularly where legumes have traditionally been part of the rotational system, yield depressions have sometimes been reported at such pH levels on highly weathered acid soils of tropical and subtropical origin.  相似文献   

18.
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   

19.
Abstract

Fluidized bed material (FBM), a dry, high Ca, alkaline waste product which results from combining coal and limestone, was used as a Ca or S source or lime substitute in an established apple orchard (Malus domestica Borkh., cv. ‘York Imperial') over a four year period. Treatment comparisons were made between FBM applied at one or two times (1x or 2x) the soil lime requirement and CaCO, applied at the lime requirement (lx). Additionally, FBM lx was compared to a combination treatment consisting of CaCO3 plus gypsum to apply similar amounts of Ca and S. All treatments were also compared to an untreated control.

No significant treatment comparisons were noted on leaf Ca levels however leaf Mg significantly decreased when FBM applied at the 1x or 2x level compared to CaCO3 1x. When FBM was compared with CaCO. plus gypsum there was a significant decrease in leaf Ca with FBM but no difference in leaf Mg. These effects were probably due to either a solubility difference between nutrients or to actual amount of Mg applied by the different sources. Leaf S levels were unaffected by treatments. Yields, fresh fruit weight and the incidence of cork spot were little affected by treatments.

Soil extractable Mg, 1N NH4Ac, was not a good prediction of leaf Mg content or Mg added to the soil. Only soil Al was significantly reduced, compared to the control, by the treatments among the metals studied (Zn, Mn, Cu, Cd, Pb and Al). FBM applied at twice the lime requirement (wt. basis) resulted in similar soil pH to CaCO3 applied at the lime requirement.  相似文献   

20.
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   

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