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1.
石灰组配土壤改良剂抑制污染农田水稻镉吸收 总被引：5，自引：2，他引：3
为达有效地调控污染稻田水稻糙米对Cd吸收,该研究选取湖南省长株潭地区的湘潭、醴陵和株洲3处不同Cd污染程度田块,研究石灰配施海泡石、钙镁磷肥、有机肥对水稻Cd吸收和累积的影响。结果表明,施用石灰及其组配改良剂均可明显提高土壤pH值,有效降低土壤中酸提取态Cd含量和水稻中Cd含量。与不施用改良剂相比,石灰配施海泡石或有机肥、配施海泡石和有机肥,Cd污染稻田土壤pH值平均升高1.08,0.96和0.93个单位,酸提取态Cd质量分数分别平均降低20.6%,15.6%和21.2%。石灰配施海泡石、有机肥或钙镁磷肥处理下在轻度Cd污染田块中糙米Cd含量较对照分别显著降低了48.3%,46.7%和34.2%,石灰配施有机肥、钙镁磷肥或钙镁磷肥和有机肥处理下在中度Cd污染田块中糙米Cd含量较对照分别显著降低了52.8%,47.8%和37.5%,石灰配施钙镁磷肥和有机肥、有机肥或海泡石处理下在重度Cd污染田块中糙米Cd含量较对照分别显著降低了51.2%,44.6%和42.5%,均低于食品安全国家标准中糙米限量值0.2 mg/kg(GB2762-2017)。相关分析表明,土壤中酸提取态Cd含量与水稻根、茎叶和糙米中Cd含量呈显著正相关关系(P0.05),说明土壤酸提取态Cd含量是影响糙米对Cd吸收的关键因素之一。上述结果说明,石灰配施海泡石、有机肥或钙镁磷肥+有机肥可有效调控污染稻田土壤中Cd进入水稻,实现水稻安全生产。 相似文献
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有机无机肥配施锌肥和石灰对双季稻产量及土壤养分特性的影响 总被引：1，自引：0，他引：1
在南方典型双季稻种植区,通过2年试验综合评价在有机无机肥配施基础上施用锌肥和石灰对双季稻产量与土壤养分特性的影响,以期提出培肥土壤和提高水稻产量的理想施肥模式。设置有机肥+无机肥(T1)、锌+有机肥+无机肥(T2)、石灰+有机肥+无机肥(T3)、锌+石灰+有机肥+无机肥(T4)4个处理,测定了土壤有效锌、碱解氮、有效锌含量和pH,分析了水稻产量和土壤综合肥力。结果表明:(1)相比T1处理,T2处理显著提高了早晚稻千粒重和结实率,显著增产8.7%,而T3处理不利于水稻稳产,显著降低了千粒重,并在第2年减产(5.6%)显著;T4处理表现出来的产量规律与T3处理类似,均于第2年表现减产。(2)施用锌肥、石灰均有利于提高土壤有效磷和碱解氮含量,石灰显著提高土壤pH,但T3、T4处理土壤有效锌含量显著下降,较T1处理分别下降39.0%和31.9%,而连年施用锌肥有利于有效锌的提高,T2较T1处理土壤有效锌含量提高22.2%。(3)土壤综合肥力表现为T2T4T1T3,施用锌肥相比石灰更有利于提高土壤肥力。综上所述,施用锌肥能显著提高土壤速效养分含量,增产显著,而连年施用石灰显著降低了土壤中有效锌含量。因此,在缺锌土壤中需慎施石灰,而长期施用石灰的土壤,应追施锌肥。综合土壤养分含量和水稻产量评价,有机+无机+锌肥的施肥模式为理想施肥模式。 相似文献
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南方红壤区磷肥当季利用率仅为10%～25%,提高磷肥利用率是亟待解决的问题。通过两年田间试验,分析了不同磷肥品种（过磷酸钙、猪粪、钙镁磷肥、磷酸一铵、磷酸二铵）、磷肥梯度（常规施磷、减磷20%、减磷30%）以及调控措施（石灰、钙镁磷肥配施磷酸二铵、钙镁磷肥配施秸秆）对红壤磷素有效性和作物生长的影响,探索提高磷肥利用率的途径。结果表明,各磷肥品种间,以猪粪处理土壤有效磷、地上部生物量、磷肥累积利用率等指标最高,土壤有效磷较不施磷处理两年分别提高了32%和241%,地上部生物量较不施磷处理两年分别提高了73%和510%,两年的磷肥累积利用率分别为16.4%和26.5%;伴随磷肥用量的减少,土壤有效磷含量显著降低,而对油菜生长、磷肥利用率及磷肥农学效率无显著影响;与单施钙镁磷肥相比,钙镁磷肥配施磷酸二铵能显著提高油菜籽粒产量、土壤有效磷含量、磷肥累积利用率、磷肥农学效率、土壤磷素盈余量等指标。添加石灰可提高作物产量及土壤有效磷含量。油菜产量与土壤有效磷呈极显著正相关关系。上述结果表明,猪粪替代化学磷肥可达到减施增效、促进作物生长的目的,且以减磷30%为宜;钙镁磷肥配施磷酸二铵可推荐为磷肥调控... 相似文献
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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
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氮锌配施对不同冬小麦品种产量及锌营养的影响 总被引：13，自引：2，他引：11
为比较石灰性土壤氮锌配施对不同小麦品种生长及锌营养的影响,选10种本地主要种植小麦品种,进行连续两年的田间试验,测定小麦产量及锌含量。结果表明,在石灰性土壤上单施锌肥和氮锌配施对小麦产量、籽粒锌含量的影响因品种而异。单施锌肥及氮锌配施处理可显著增加土壤有效锌含量,但单施锌肥处理仅增加"西杂1号"、"武农148"、"郑麦9023"籽粒锌含量;氮锌配施增加除"小偃22"外其余9种供试小麦品种籽粒锌含量,增幅为7.3%～54.7%。单施锌肥对小麦锌累积量增加的效果不明显;氮锌配施可显著增加小麦地上部锌累积量,两季分别增加6.5%、29.8%。单施氮肥可显著增加小麦锌吸收,但其主要累积在小麦茎叶部。在石灰性土壤上,单施锌肥虽显著增加了土壤有效锌含量,但对小麦产量及籽粒Zn含量增加有限,氮锌肥配施可取得较好效果。 相似文献
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不同措施改良反酸田及水稻产量效果 总被引：4，自引：0，他引：4
【目的】针对反酸田土壤酸性强、有效磷含量极低、活性铝铁毒性重及结构性差等特征,研究不同措施改良反酸田土壤理化性质,提高水稻产量的效果,为施用合理的改良剂消减各种障碍因素、提高土壤肥力、恢复土壤生产力提供理论依据。【方法】通过三年田间定位试验,设置不施肥(CK1)、专用肥(NPK,CK2)、NK+钙镁磷肥、NK+磷矿粉、专用肥+石灰、专用肥+粉煤灰、专用肥+生物有机肥7个处理,研究不同改良措施对华南稻区反酸田水稻产量、土壤酸度、养分状况、团聚体及腐殖质组分的影响。【结果】连续3年添加改良剂钙镁磷肥、磷矿粉、石灰、粉煤灰和生物有机肥的处理早、晚稻平均产量较CK1处理均显著增加,其增幅分别为38.78%~75.00%和38.31%~56.75%;与CK2处理相比,添加改良剂的处理三季早稻和两季晚稻平均产量均有所增加,其增幅分别为9.15%~26.10%和5.71%~13.33%,且添加石灰、粉煤灰和生物有机肥的处理水稻增产率大于钙镁磷肥和磷矿粉处理。添加改良剂的处理土壤p H、有效磷和速效钾含量较CK1和CK2处理均有所增加,而交换性H+、交换性Al3+、有效硫含量则显著降低。与CK1和CK2处理相比,各添加改良剂处理5 mm粒级水稳性团聚体占团聚体比例均显著提高,而2~1 mm、1~0.5 mm以及0.5~0.25 mm粒级团聚体所占比例均有所下降。添加粉煤灰和生物有机肥处理有利于提高0.25 mm水稳性团聚体数量及稳定性,其团聚体破坏率分别降低至14.11%和16.99%。与CK1处理相比,添加石灰处理土壤有机碳含量略有下降,而其他施肥处理均有增加;各施肥处理土壤胡敏酸碳和胡敏素碳含量较CK1处理均有增加,而富里酸碳含量均呈下降趋势。与CK2处理相比,连续3年添加钙镁磷肥和生物有机肥的处理显著提高了土壤总有机碳含量,添加粉煤灰和生物有机肥处理显著提高了土壤水溶性碳和胡敏酸碳含量。施肥处理HA/FA比值较CK1处理均有所提高,其增幅为16.44%~47.69%;与CK2处理相比,添加粉煤灰、生物有机肥处理其值增幅最大,分别提高26.83%和24.53%。【结论】添加粉煤灰或生物有机肥处理对反酸田土壤的改良效果最佳。 相似文献
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麦秆还田对作物产量影响以及秸秆还田如何施肥是农业生产者极为关注的问题,为了明确豆麦轮作麦秆长期还田对作物产量及对土壤化学性质的影响,该文依托黑河市长期定位实验站,采用裂区试验方法,主处理为秸秆还田与不还田处理,副处理为低、中、高不同施肥水平,试验于1980年开始,轮作模式先后为麦-豆-麦和麦-豆轮作模式,通过连续38 a(1980—2018年)调查,探明麦豆轮作条件下麦秸还田及不同施肥水平对作物产量影响。结果得出:麦秸还田后种植大豆、小麦,多年产量与不还田比差异不显著(P0.05);连续施肥效果,大豆中肥区比低肥区增产7.42%～10.81%,达到差异显著水平,小麦高肥区比低肥区增产14.52%～19.33%,差异极显著(P 0.01);麦秸还田大豆增产效果,还田前期(1～6季)大豆平均产量比不还田增产5.91%,后期(7～16季)平均增产7.52%,麦秸还田小麦增产效果,还田前期(1～5季)和后期(6～16季)平均增产0.31%、0.22%,后期增产频率高;麦秆隔年还田显著增加速效钾含量,施肥可以有效增加土壤碳、氮、磷含量,但长期高肥易导致土壤酸化。 相似文献
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为探寻有效的芒果园酸性土壤改良措施,采用田间试验的方法研究了酸性土壤单施石灰、单施有机肥、混施石灰+有机肥对土壤生物和化学特性及芒果生长与品质的影响。结果表明:单施有机肥或单施石灰可显著增加土壤阳离子交换量和交换性盐基离子总量,其中单施有机肥可显著提高土壤有机质、碱解氮和有效磷含量,但对土壤酸度无显著影响,而单施石灰可显著降低土壤酸度,但对土壤养分无显著影响,石灰和有机肥混施土壤水解性酸和交换性酸含量降低,土壤pH上升0.38个单位,土壤有机质、碱解氮和有效磷含量增加62.01%～78.38%,且可增加土壤阳离子交换量和交换性盐基离子总量,其盐基饱和度提高13.37个百分点。单施石灰或石灰与有机肥混施可使土壤脲酶、蔗糖酶和过氧化氢酶活性提高7.63%～54.20%,但酸性磷酸酶活性降低12.34%～27.06%,而单施有机肥则可使此4种土壤酶活性提高4.55%～58.75%;单施石灰、单施有机肥或有机肥与石灰混施均可提高土壤微生物活性、叶片叶绿素含量、比叶重、芒果单果重、果实品质和产量,单施有机肥果树叶片质量、果实产量及果实可溶性固形物高于单施石灰,但果实糖酸比低于单施石灰,综合来看,石灰与有机肥混施效果最佳,其微生物量碳含量提高163.85%,微生物熵提高48.73%,单果重、糖酸比和产量分别提高20.88%、64.00%、54.70%。综上,单施石灰或单施有机肥均可一定程度地改良芒果园酸性土壤,但两者混施效果最佳,因此,石灰+有机肥混施是一种有效的可持续的芒果园酸性土壤改良方法。 相似文献
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改良剂对重金属污染红壤的修复效果及评价 总被引：10，自引：0，他引：10
采用盆栽试验,研究了施用改良剂—石灰、有机肥、海泡石对红壤上小油菜生物产量、镉锌吸收量、pH、吸收系数的影响。结果表明,施用改良剂,连续种植3季小油菜 (Brassia campestris L.) 的生物产量都显著提高,石灰、有机肥和海泡石配施的产量是对照的15倍。改良剂能不同程度提高红壤的pH,以石灰的效果最好,土壤pH平均升高了2个单位;而且小油菜对镉锌的吸收也较低。小油菜对镉的吸收系数大于对锌的吸收系数,说明镉容易在土壤-植物体系中迁移,施用改良剂后吸收系数降低。施石灰的小油菜中锌含量达到食品卫生标准。改良剂对提高土壤pH的后效逐渐减弱,对抑制小油菜吸收锌的后效不如抑制镉的后效好。 相似文献
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Mariane Wolf Dilmar Baretta Valter A. Becegato Vitor de C. Almeida Alexandre T. Paulino 《Water, air, and soil pollution》2017,228(4):152
Copper/zinc bioaccumulation and the effect of phytotoxicity on the growth of lettuce (Lactuca sativa L.) were studied in plastic vessels containing (i) non-contaminated soil, (ii) copper-contaminated soils at concentrations of 75.0 and 125.0 mg kg?1, (iii) zinc-contaminated soils at concentrations of 1200 and 2400 mg kg?1, and (iv) soil enriched with swine manure. Copper and zinc concentrations in lettuce leaves were determined by flame atomic absorption spectrometry during 42 days of growth. Copper concentrations from 0.92 to 13.06 mg kg?1 were found in lettuce leaves grown in copper-contaminated soils and zinc concentrations from 58.13 to 177.85 mg kg?1 were found in lettuce leaves grown in zinc-contaminated soils. Copper and zinc concentrations in lettuce leaves grown in swine manure-enriched soils ranged from 0.82 to 8.33 and 0.68 to 13.27 mg kg?1, respectively. Copper and zinc bioaccumulation caused a decrease in lettuce growth in metal-contaminated soils and an increase in phytotoxicity effects when compared to growth in non-contaminated and manure-enriched soils. These findings were confirmed by measuring leaf areas and biomasses. Copper was less toxic to lettuce than zinc due to the different concentrations in the soil. Lettuce growth and development was better in the swine manure-enriched soil than non-contaminated soil, which indicates that swine manure is a safe agricultural biofertilizer when used in appropriate amounts to avoid metal bioaccumulation in soil and plants. 相似文献
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采用外源加入重金属铜锌硝酸盐的方法,制成铜、锌单一及复合污染的三级污染红壤和黄泥土（Cu 200mg/kg、Zn 400 mg/kg）,稳定一个月,施入低（0.50 g/kg）、中（1.50 g/kg）和高（2.50 g/kg）3种不同用量的石灰,稳定两个月后测定土壤有效态铜、锌含量和pH值,以阐明石灰用量对不同污染土壤中重金属有效态含量的影响。结果表明,随石灰用量的增加,复合污染红壤中有效态铜含量较对照依次降低31%、76%和87%;而石灰用量对黄泥土中有效态铜影响的差异不显著;两种土壤中有效态锌含量均随石灰用量的增加而显著减少;复合污染较单一污染相比,有效态铜及有效态锌的含量差异不显著。在复合污染下,低、中量石灰使黄泥土中有效态铜含量较红壤减少89%和63%,有效态锌减少27%和65%。但加入高量石灰,两种土壤差异不显著。石灰能够降低单一与复合污染铜、锌有效态的含量,但其效果因土壤类型而异,在红壤上选择施用高量石灰而在黄泥土上则适宜施用低中量石灰,以取得最佳的修复效果和效益。 相似文献
13.
石灰与磷肥可以降低华南5种常见蔬菜对镉的吸收量 总被引：7，自引：0，他引：7
A pot experiment was conducted in artificially Cd-contaminated (5 mg Cd kg-1) soils to investigate the feasibility of using lime (3 g kg-1) or phosphate (80 mg P kg-1) to mitigate uptake of Cd by vegetables.Five common vegetables in South China,including lettuce (Lactuca sativa L.var.ramosa Hort.),Chinese cabbage [Brassica rapa L.subsp.Chinensis (L.) var.parachinensis (L.H.Bailey) Hanect],Chinese broccoli (Brassica oleracea L.var.albiflora Kuntze),white amaranth (Amaranthus tricolor L.) and purslane (Amaranthus viridis L.),were grown in the soils and harvested after 60 d.The results showed that liming significantly reduced Cd uptake by most vegetables by 40%-50% (or a maximum of 70%),mainly due to immobilization of soil Cd.Increased availability of Ca in the soil might also contribute to the Cd uptake reduction as a result of absorption competition between Ca and Cd.Liming caused biomass reduction in white amaranth and purslane,but did not influence growth of the other vegetables.Phosphate decreased Cd uptake by vegetables by 12%-23%.Compared with lime,phosphate decreased,to a smaller extent,the bioavailability of Cd in most cases.Phosphate markedly promoted growth of vegetables.Changes in soil chemistry by adding lime or phosphate did not markedly influence nutrient uptake of vegetables except that lime increased Ca content and phosphate increased P content in shoots of the vegetables.The results suggested that a proper application of lime could be effective in reducing Cd uptake of vegetables,and phosphate could promote growth of the vegetables as well as alleviate the toxicity of Cd. 相似文献
14.
《Communications in Soil Science and Plant Analysis》2012,43(16):1986-2003
We assessed cadmium (Cd) and zinc (Zn) availability when applying reactive phosphate rock (RPR) in combination with lime and chicken manure on Indonesian acidic upland soils. Maize plants were grown on unamended soil and soils treated with several combinations of 2 tons dolomite ha–1, 2 tons of chicken manure ha–1, 1 ton ha–1 of RPRL (reactive phosphate rock containing 4 mg Cd kg–1 and 224 mg Zn kg–1), and 1 ton ha–1 of RPRH (RPR containing 69 mg Cd kg–1 and 745 mg Zn kg–1). In addition to its positive effect on plant yield, application of RPR in combination with chicken manure did not result in toxic Cd concentrations. Although liming is effective to reduce plant Cd concentrations, it results in more soil Cd accumulation and more plant Zn deficiency. Cadmium and Zn concentrations in shoots and grains can be predicted well from amounts extracted from the soil by 0.5 M ammonium (NH4) acetate + 0.02 M ethylenediaminetetraacetic acid (EDTA) at pH 4.65. 相似文献
15.
猪粪对红壤铝毒的缓解效应 总被引：15，自引：4，他引：15
利用盆栽实验研究了施用猪粪和石灰对红壤铝毒的缓解效应。结果表明 ,在对照土壤 (pH 4.2)上生长的小麦遭受铝毒害明显 ,出苗后 36d全部枯死 ,施用石灰和猪粪能不同程度地缓解铝毒害。施用猪粪和石灰都可以提高土壤pH ,降低交换性铝含量。与单施石灰相比 ,石灰猪粪混施可以提高土壤 pH ,降低交换性铝含量 ,增加小麦叶绿素含量、光合速率和地上部干物重。与单施猪粪相比 ,石灰猪粪混施使小麦地上部K、Mg和P含量减少。 相似文献
16.
Tapas Kumarpandit Sushanta Kumarnaik Prasenjit Kumar Patra Nilanjan Dey Dilip Kumar Das 《Communications in Soil Science and Plant Analysis》2017,48(4):357-369
Spinach grown in cadmium (Cd)-contaminated soils accumulates Cd compounds in toxic concentration contaminating the food chain leading to the chronic toxic effects on human and animal health. A study was conducted in a Cd-contaminated soil to examine the ameliorative effect of lime and organic manure on the mobility of Cd and its uptake in spinach. Application of lime or organic manure or both decreased the Cd concentration in soil and shoots and increased chlorophyll content of leaves. As compared to the control treatment, combined application of lime and organic manure decreased the level of Cd in soil by 54.7%, in spinach shoot by 61.3%, and the transfer factor of Cd by 35.0% and increased in leaf chlorophyll content by 29.4%. Combined application of lime and organic manure emerged as a viable option in reducing the mobility of Cd in contaminated soil for growing spinach. 相似文献
17.
活化磷矿粉对重金属污染土壤上莴苣生长与品质的影响 总被引：2，自引：0，他引：2
用0.5 mol/L草酸与南漳和保康两地的两种低品位磷矿粉在一定条件下混合培养后,施于重金属污染的土壤,通过盆栽试验,研究草酸活化磷矿粉对重金属污染土壤上莴苣生长和品质的影响。结果表明,盆栽试验中,与对照相比,施加磷矿粉和活化磷矿粉后,莴苣的株高、 叶片叶绿素SPAD值、 叶片和茎的维生素C含量都有不同程度的提高,其效果为活化磷矿粉＞磷矿粉＞对照,而叶和茎的硝酸盐含量则降低。同时,施加磷矿粉和活化磷矿粉可以提高土壤有效磷、 交换性钙、 镁含量,降低交换态重金属含量,进而降低莴苣各部分对重金属元素的吸收,如施加活化磷矿粉后莴苣根中Cd、 Cu的含量比对照最高可降低55.1%、 55.24%,地上部分中Cd、 Cu的含量比对照最高可降低59.3%、 53.4%,降低重金属含量的效果依次为活化磷矿粉＞磷矿粉＞对照。 相似文献
18.
改良剂对镉污染酸性水稻土的修复效应与机理研究 总被引：29，自引：0，他引：29
为探明田间条件下施用石灰、钙镁磷肥、海泡石和腐殖酸等改良剂对Cd污染酸性水稻土的修复效应和作用机理, 通过在Cd污染区建立田间小区试验, 研究了改良剂单施和与石灰配施对Cd污染酸性水稻土中Cd作物有效性的影响。结果表明, 施用改良剂有效地改变了土壤中Cd的存在形态, 除腐殖酸外, 其他改良剂均使土壤酸提取态Cd不同程度地转化为可还原态Cd和残渣态Cd; 施用改良剂可使0.1 mol·L-1 NaNO3和 0.01 mol·L-1CaCl2提取态Cd 降低26%~97%, 降低效果为石灰+海泡石>海泡石>石灰+钙镁磷肥>钙镁磷肥>石灰>石灰+腐殖酸>腐殖酸; 改良剂使水稻地上部分的Cd吸收量降低6%~49%。试验结果还显示, 施用改良剂提高土壤pH是引起土壤中Cd作物有效性降低的主要原因之一。根据田间试验的结果, 海泡石可推荐作为Cd污染酸性水稻土的改良剂, 而腐殖酸则不宜使用。 相似文献
19.
《Journal of plant nutrition》2013,36(7):967-977
Animal manures contain significant amounts of plant-available nutrients which could increase crop yields. They also contain heavy metals which may be exported outside soil systems by plants, animal and surface and underground water following application to soils. The effect of some animal manures on rice yield and extractability of iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) were determined in fours soils with different properties. The manures were applied at the rate of 100Mg ha?1, and rice was grown for two consecutive seasons. In the second of the two seasons, rice yield and yield components were determined. Immediately after the second season rice harvest, soils were sampled and analyzed for DTPA extractable Fe, Zn, Mn, and Cu. Averaged across the soils, the level of extractable Fe increased by between 5% in chicken manure (PM) and 71% in cattle manure (CM); Zn by between 312% in CM and 871% in swine manure (SM); Mn by between 61% in PM and 172% in SM and Cu by between 327% in PM and 978% in SM. Mixing these manures before application reduced the level of extractable trace elements. Although there was increased yield following application, the results of this study indicated a possible risk of trace element export to the environment within a year, if high levels of the manures are applied. 相似文献
20.
《Communications in Soil Science and Plant Analysis》2012,43(5-6):755-762
Abstract Highly weathered tropical soils are characterized by having a predominantly variable charge. Many management practices commonly used in the exploitation of these soils (e.g., liming, phosphate application, and manuring) are known to modify their electrical charge and the sorption/desorption behavior of cations and anions. This process is, at least, partially governed by the charges existing in the soil system. Available information on this subject comes mainly from short‐term laboratory and greenhouse experiments. There is a lack of data regarding the cumulative and long‐term effects of those practices used at farm‐scale levels and on the dynamics and availability of nutrients to the plants under field conditions. In the present work, changes in some electrochemical attributes of a variable charge soil (Oxisol) were studied, as influenced by treatments with phosphate + green manure (Cajanus cajan), phosphate + lime, and phosphate + lime + green manure, applied during a six‐year period. In this period, rice, bean, wheat, or corn, were grown in seventeen successive crops. Phosphate (total 334 ppm P) and phosphate + lime (total 5.5 t ha‐1) were shown to increase net electric charge and soil cation exchange capacity (CEC) at the field pH, and not to affect zero point of charge (ZPC), CEC at pH 7.0, or anion exchange capacity (AEC) of the soil at the field pH. The effects of phosphate + lime were more pronounced than those of phosphate alone. Green manure (total 16 t ha‐1 dry matter), associated to crop residues and phosphate or phosphate + lime, did not influence electrochemical properties. 相似文献