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1.
以磷高效型小麦洛夫林和磷低效型小麦中国春为试材设计三室根箱试验,通过测定两品种小麦生物量、吸磷量、pH值和酸性磷酸酶活性,对比它们在两种磷水平(P 0 mg/kg、P 100 mg/kg)及两种土壤(石灰性黑垆土、酸性红壤)上的根际特征差异。结果表明,黑垆土上增施磷肥,洛夫林和中国春的总生物量分别增加了30.14%和17.75%,总吸磷量分别增加了139.24%和71.72%;红壤上增施磷肥,两小麦总生物量并没有显著增加。根际pH方面,黑垆土上,不施磷条件下,洛夫林和中国春的根际pH值分别降低0.30和0.12个单位,但在红壤上两小麦根际pH值变化不大。酸性磷酸酶方面,PO条件下,黑垆土上两小麦根际酸性磷酸酶活性差异不显著,但红壤上洛夫林酸性磷酸酶活性显著高于中国春。P100条件下,黑垆土上洛夫林酸性磷酸酶活性显著高于中国春,而红壤上两小麦酸性磷酸酶活性差异不大。试验结果表明,在黑垆土和红壤上,两种磷效率小麦根际特征存在差异。  相似文献   

2.
以磷高效型小麦小偃54和磷低效型小麦京411为研究对象设计三室根箱试验,通过测定生物量、吸磷量、pH和酸性磷酸酶,对比两种小麦在不同磷水平(P0 mg/kg土、100 mg/kg土)及两种不同土壤上(石灰性黑垆土、酸性红壤)根际特征的差异。试验结果表明,黑垆土上,增施磷肥使小偃54的总生物量增加了14.99%,京411增加了26.53%,总吸磷量二者分别增加了99.29%和83.70%;红壤的速效磷含量高,施肥仅提高了磷低效型小麦京411的生物量。黑垆土上磷胁迫并未造成小偃54与京411各部分生物量和吸磷量的显著性差异,但小偃54的根际pH降低值和酸性磷酸酶的活性却已显著高于京411;P0处理时,红壤上小偃54的地上部和总生物量显著高于京411,虽然红壤的速效磷含量高于黑垆土,但在P0处理时两种小麦在两种土壤上的生物量和吸磷量并无显著性差异。就根际分泌物而言,石灰性黑垆土上,小偃54的根系在低磷胁迫下通过降低pH和分泌酸性磷酸酶来活化土壤中难溶态的磷,而在红壤上小偃54的pH和酸性磷酸酶的活性保持稳定。酸性红壤中两种小麦酸性磷酸酶活性显著高于石灰性黑垆土。由此可见,两种磷效率小麦在两种不同性质土壤上活化机理存在差异。  相似文献   

3.
【目的】研究适宜施氮条件下磷富集植物粗齿冷水花的磷积累能力,可为有效利用该植物提取土壤中过剩的磷、减少磷的面源污染提供理论依据。【方法】以两种生态型粗齿冷水花 (Pilea sinofasciata) 为研究对象,进行土培盆栽试验,供试土壤为灰潮土,每盆 (8 L) 装土8 kg。分别施磷0、400、600、800 mg/kg,陈化8周。幼苗种植前,每盆施入140 mg/kg尿素。移栽9周后收获,测定植株生物量、磷含量,分析了土壤速效磷含量。【结果】1) 在供试施磷量范围内,两种生态型粗齿冷水花地上部、地下部生物量在施磷600 mg/kg时达最大,此时矿山生态型地上部、地下部生物量分别是其不施磷对照的2.37和3.69倍,非矿山生态型地上部、地下部生物量是其不施磷对照的4.63和7.36倍,矿山与非矿山生态型地上部生物量最大值分别可达28.6 g/株和31.9 g/株。矿山生态型生物量在不施磷和施磷400 mg/kg时显著大于非矿山生态型,在施磷600、800 mg/kg时两生态型间无明显差异。2) 随施磷量增加,两种生态型粗齿冷水花地上部磷含量和矿山生态型地下部磷含量均表现为先升高后降低,在施磷800 mg/kg时显著降低,而非矿山生态型地下部磷含量随施磷量增加而增加,在施磷800 mg/kg时达最高。各磷处理下,矿山生态型地上部磷含量均显著高于非矿山生态型,而地下部磷含量低于非矿山生态型。3) 高磷处理显著增加了两种生态型粗齿冷水花地上部、地下部磷积累量,且在施磷600 mg/kg时植株磷积累量最大,矿山生态型与非矿山生态型地上部磷积累量最高分别可达195 mg/株和182 mg/株。在不施磷和施磷400 mg/kg时,矿山生态型地上部磷积累量显著高于非矿山生态型,在施磷600、800 mg/kg时两生态型间无明显差异。4) 不同磷处理下,两种生态型磷富集系数远大于1,磷转移率大于80%;矿山生态型的磷提取率和移除量在不施磷和施磷400 mg/kg时均大于非矿山生态型,在施磷600、800 mg/kg时两生态型间无明显差异。【结论】适宜施氮条件下,粗齿冷水花在施磷600 mg/kg时表现出较强的磷富集能力。与非矿山生态型相比,矿山生态型在不施磷和施磷400 mg/kg时对磷的积累能力和富磷潜力更强;在施磷600、800 mg/kg时两生态型植株对土壤磷的富集能力无明显差异。  相似文献   

4.
采用盆栽试验的方法,研究不同磷添加量(0,20,80 mg/kg)和土霉素添加量(0,40,160 mg/kg)对小麦和紫花苜蓿幼苗生物量及根系发育的影响。结果表明:所有水平土霉素处理中,20,80 mg/kg磷处理的小麦地上部生物量均比不加磷时高,分别高22.7%～34.1%,10.0%～30.0%和9.1%～18.3%。除160 mg/kg土霉素加80 mg/kg磷的处理外,所有处理的苜蓿根生物量均小于不加磷和土霉素的对照。小麦的根长和根表面积随着土霉素添加量的增加总体上呈减少的趋势。总体来看,施磷显著促进了小麦幼苗地上部的生长,但对苜蓿幼苗生长的影响不显著。土霉素对苜蓿幼苗的根系发育有抑制作用。研究结果可为评价土壤中土霉素残留对作物早期生长的影响和指导合理施用磷肥提供理论依据。  相似文献   

5.
通过盆栽和模拟实验探讨了水分状况和施磷量对红壤有效磷的影响。结果表明,水分状况和施磷量均显著地影响红壤有效磷含量,二者的交互作用达极显著水平;同时也均显著地影响水稻生物量和对磷的吸收量,二者的交互作用达显著和极显著水平。红壤有效磷含量基本上随红壤水分含量和施磷量的增加而提高,随水稻生长时间的延长而降低;水稻的生物量和对磷的吸收量均随施磷量的增加和水稻生长时间的延长而增加,但以中水条件下最高。在保证80%的饱和持水量和常规氮、钾等养分投入条件下,施磷量为67.5 kg hm-2就可以满足水稻旱作的生长需求。  相似文献   

6.
  【目的】  基于关中平原冬小麦施磷量与小麦磷营养的关系,建立临界磷浓度稀释曲线,为当地冬小麦科学施磷提供理论依据。  【方法】  长期定位施磷田间试验始于2009年,供试小麦品种为‘西农979’。设置4个施磷水平(P2O5) 0、60、120、180 kg/hm2,分别记为P0、P60、P120和P180处理。于2018—2021年冬小麦拔节期、孕穗期、开花期、灌浆期和成熟期取样,分析冬小麦地上部生物量、植株磷浓度,记录小麦产量。利用2018—2020年冬小麦地上部生物量和植株磷含量建立临界磷浓度稀释模型,计算磷营养指数 (PNI)。依据2020—2021年冬小麦数据验证磷营养指数诊断的可靠性。  【结果】  1) 施用磷肥可显著增加冬小麦穗数和穗粒数,显著降低千粒重,2018—2021年3季冬小麦依次提高穗数50.7%～53.0%、23.1%～29.7%和17.5%～19.0%,穗粒数依次提高28.6%～34.2%、22.7%～24.1%和18.7%～19.6%,千粒重依次降低1.1%～2.9%、3.5%～7.0%和1.3%～4.9%,P60、P120和P180处理间穗数、穗粒数(2018—2019年除外)差异不显著。随着施磷量增加,冬小麦籽粒产量先持续增高而后降低,施磷处理下2018—2021年3季冬小麦依次增产104.3%～108.2%、39.8%～47.4%和27.6%～32.5%,在P120处理下产量达到最大值,2018—2021年3季依次为7100、6369和6714 kg/hm2。2) 冬小麦地上部生物量随生育进程的推进逐渐增加,地上部磷浓度随生育进程推进逐渐降低。同一取样时期,施磷量增加,地上部生物量和磷浓度也随之增加。据此,本研究2019—2020年建立的临界磷浓度稀释曲线模型为Pc=6.00DM–0.43,模型RMSE值为0.09,n-RMSE值为3.45%,表明模型模拟值的可靠性和稳定性达到要求。3) 随着施磷量增加,磷营养指数 (PNI) 增大,磷营养指数 (PNI) 在P120处理下最接近1。各施磷量处理下,冬小麦磷营养指数 (PNI) 随生育期的变化较小。  【结论】  依据不同施磷量下冬小麦地上部生物量和磷浓度,建立的临界磷浓度稀释曲线模型与磷营养指数 (PNI) 模型能够准确诊断关中平原冬小麦不同生育阶段的磷素盈亏状况,可用来指导关中平原冬小麦植株各生育期磷素含量评估和磷肥施用。  相似文献   

7.
适量施磷有效提高苋菜对镉污染土壤的修复能力   总被引：1，自引：0，他引：1  
  【目的】  土壤性质和化肥施用均影响作物对重金属污染土壤的修复效果。探究不同磷肥施用量对苋菜镉 (Cd) 吸收和累积的影响,为通过养分管理减少作物对重金属的积累提供依据。  【方法】  以苋菜 (Amaranshus mangostanus L.) 为供试作物,以黄棕壤和赤红壤为供试土壤进行盆栽试验。在两个供试土壤中,加入分析纯CdCl2?2.5H2O (Cd 15 mg/kg土), 平衡一个月后,用于苋菜栽培。设置5个磷肥（P）施用水平:0 (CK)、50、100、200、400 mg/kg土,以磷酸二氢铵 (分析纯) 加入。苋菜生长45天后收获,调查地上部和根部生物量,分析其磷、镉含量,并测定土壤中DTPA提取的有效态Cd含量。  【结果】  施用磷肥能提高苋菜的生物量,随着施磷量的增加,苋菜生物量也随之增加,且各处理均与CK处理差异显著。在黄棕壤上,苋菜地上部生物量增幅为9.2%～39.0%,根部为4.0%～15.0%;在赤红壤上,苋菜地上部增幅为7.7%～46.0%,根部为10.0%～100.0%。苋菜Cd含量与CK处理相比均显著降低,在黄棕壤上,苋菜地上部和根部Cd含量的降幅分别为7.4%～50.2%和7.9%～58.8%;在赤红壤上,降幅分别为9.9%～55.8%和21.7%～66.0%。苋菜Cd累积量与CK处理相比均呈上升趋势,黄棕壤上苋菜地上部和根部Cd累积量的增幅分别为36.2%～54.3%和7.4%～38.9%;在赤红壤上,增幅分别为34.3%～62.8%和5.4%～55.4%。当施磷量为P 50 mg/kg土时,苋菜地上部、根部在黄棕壤和赤红壤上的Cd累积量均最大。施磷降低了土壤中镉的生物有效性。随着施磷量的增加,土壤有效态Cd含量显著降低,黄棕壤上的降幅为0.9%～7.2%,赤红壤上的降幅为1.2%～7.9%。植株体内Cd含量与磷含量之间存在一定的负相关性。  【结论】  施用磷肥显著提高苋菜的生物量,同时降低土壤中有效态镉的含量。虽然施磷肥显著降低了苋菜地上部和根部的Cd含量,但显著提高的生物量有效增加了苋菜对土壤Cd的总吸收和累积量,提高了其对镉污染土壤的植物修复效率。盆栽结果表明,在镉浓度为15 mg/kg 土的黄棕壤和赤红壤上,磷肥施用量为50 mg/kg土时修复效果最佳。  相似文献   

8.
不同土壤水分条件下施磷量对小麦旗叶衰老及产量的影响   总被引：1，自引：0，他引：1  
在防雨旱棚池栽条件下研究了水分胁迫(W1)和水分适宜(W2)条件下不同施磷量对小麦旗叶衰老及产量的影响.结果表明,小麦开花后,W1水平下,施磷150 kg/hm~2处理的超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)下降幅度及丙二醛(MDA)上升幅度较其他处理小;W2水平下,随施磷量的增加,SOD、POD和CAT活性增加、MDA降低,可见水分胁迫下适宜的施磷量以及适宜的水分条件下增加施磷量均可以改善小麦体内的保护酶,增加小麦叶面积指数和旗叶叶绿素含量,提高光合速率,进而延缓衰老,提高产量.本试验条件下,虽然75%土壤田间持水量与施磷量150 kg/hm~2的处理组合达到了最高产量,但与55%土壤田间持水量与施磷量150 kg/hm~2的处理组合的产量差异不显著,综合观之,后者是最佳水肥处理组合.  相似文献   

9.
以玉米为试验材料,采用分根装置(设置A、B根室),研究了不同锌水平下局部施磷或整体施磷对玉米生长以及锌、磷含量的影响。试验设置3个磷水平(0、100、200 mg/kg,分别记为P0、P100、P200),两个锌水平(0、5 mg/kg,分别记为Zn0、Zn5)。玉米生长40 d后收获,测定其地上部与地下部生物量、磷、锌元素含量。结果显示,无锌供应条件下,所有处理地上部和地下部的生物量随施磷水平的提高而显著增加,供锌处理后,生物量变化也有相同的趋势。局部施磷导致施磷一侧地下部生物量显著增加。玉米植株磷含量会随施磷水平的提高而增加,而锌含量呈相反的变化趋势。供锌条件下,供磷(P100、P200)一侧(B室)相对未供磷(P0)一侧(A室)锌含量分别显著降低了16.7%和16.1%;不供锌条件下,锌含量分别降低了13.1%和19.9%。玉米植株锌吸收量与根部生物量(B室)的比值随施磷水平的增加呈下降趋势,且相对于均匀施磷,局部施磷条件导致B室的这一比值显著降低。局部施磷方式加剧了磷对锌的拮抗作用,抑制了根对锌的吸收,同时磷水平的提高抑制锌由地下部向地上部转运;磷、锌拮抗作用的发生是玉米植株的整体反应,而非只发生在局部。  相似文献   

10.
施磷对镉胁迫下黄瓜苗期光合作用及抗氧化酶系统的影响   总被引：1，自引：0，他引：1  
  目的  探究石灰性土壤中施磷对镉胁迫下黄瓜苗期光合作用及抗氧化酶系统的影响,为合理施用磷肥、缓解镉毒害提供依据。  方法  采用盆栽完全组合设计方案,研究了不同土壤镉添加水平（0、1、3和5 mg kg?1土）下施加不同浓度磷（0、50、100、150和200 mg P2O5 kg?1土）对黄瓜苗期生物量、叶片光合作用及抗氧化酶系统的影响。  结果  随着施Cd量的增加,黄瓜生物量先增后降,黄瓜叶片的净光合速率（Pn）、气孔导度（Gs）、蒸腾速率（Tr）显著降低,胞间CO2浓度（Ci）呈上升趋势。施加适量磷（≤ 150 mg P2O5 kg?1）能够显著提高黄瓜生物量、Pn、Gs、Tr、叶绿素总量和类胡萝卜素含量（Car）,降低叶片中Ci。对于抗氧化酶系统来说,随着施Cd量的增加黄瓜叶片中过氧化物酶（POD）、过氧化氢酶（CAT）活性显著降低,丙二醛（MDA）含量明显增加。施磷后,能够明显增强抗氧化酶系统。施Cd量为1 mg kg?1,施磷量为50和100 mg P2O5 kg?1时,CAT活性增加了1.9% ~ 9.6%。施Cd量为3和5 mg kg?1时,随着施磷量的增加,POD和CAT活性出现不同程度增加,与不施磷相比,POD活性分别增加了149.1% ~ 197.8%和150.4% ~ 252.0%,CAT活性分别增加了5.8% ~ 16.6%和0.55% ~ 19.4%,其中施磷量为100 mg P2O5 kg?1时黄瓜叶片POD和CAT活性达到最大。同时,施P能够降低叶片中MDA含量,且随着施磷量的增加而降低。  结论  在石灰性土壤中,施磷量为100和150 mg P2O5 kg?1时,能够明显缓解镉毒害,增强黄瓜叶片的光合作用及抗氧化酶系统,而施磷量达到200 mg P2O5 kg?1时则对黄瓜生长产生抑制作用。  相似文献   

11.
A two-year field trial was conducted at Al-Marj Research Center, northeast Libya, during the summers of 1996 and 1997 to examine the effect of nitrogen (N) fertilizers on corn (Zea mays L.) growth in a Libyan soil (fine mixed thermic, Typic Haploxerolls) amended with different calcium carbonate (CaCO3) levels. Two N fertilizer sources (urea and diammonium phosphate, or DAP) were used at three application rates (0, 80, and 160 kg N/ha). The CaCO3 treatments were 1%, 6%, and 12% based on the soil weight of a 15 cm furrow slice. A basal phosphorus (P) dose of 46 kg P2O5/ha as triple superphosphate was applied to all experimental plots before planting. The experimental plots were arranged in a randomized split-split plot design with three replications. The parameters measured included corn grain weight, plant dry-matter content, leaf contents of N, P, potassium (K), calcium (Ca), and magnesium (Mg). The plant dry matter and corn-grain yield were significantly decreased by CaCO3, but were significantly increased by N fertilizer rates. Average grain yield dropped from 8 to 3 Mg/ha at 1% and 12% soil CaCO3 content, respectively. Generally, the N source did not have a significant effect on dry matter or on grain yield. The negative effect of CaCO3 on yield was associated with concomitant significant reduction in leaf N, P, K, and Mg contents, and an increase in Ca content. However, the leaf levels of these nutrients were considered sufficient for corn growth. Therefore, the reduction of leaf-N by CaCO3 in fertilized soils might have been the major cause of corn dry-matter and grain-yield reductions.  相似文献   

12.
The variation in and relationships between aluminum and other major metals including Ca, Mg, Mn, and K in root‐zone soil solutions were studied by growing buckwheat (Fagopyrum esculentum Moench. cv. Jiangxi), an Al accumulator, in pots filled with an acid soil amended with CaCO3 and unamended controls with a preinstalled nondestructive soil‐solution sampler. Soil solutions were collected every 7 d with a syringe connected to the sampler. The results showed that pH of the soil solution was not the only factor controlling the concentration of Al. Significant positive linear correlations were found between Al and Ca as well as between Al and Mg in soil solutions from the controls. The ratio of base cations (BC, Ca+Mg) to Al might partly explain the high Al resistance of buckwheat. Oxalate secretion from roots significantly activated Al in acid soils, which may be important for changes of Al in soil solutions, but it also caused decreased concentrations of Ca, Mg, and Mn. It is concluded that the variation of metal concentrations including Al, Ca, Mg, and Mn is a holistic effect involving competition for exchange sites among Ca, Mg, H, and Al, the chelation by oxalate secreted from roots, and metal uptake by buckwheat.  相似文献   

13.
Abstract

The large amounts of coal combustion by‐products (CCBs) generated by coal burning power plants must be utilized or discarded, and beneficial use of these materials are desired. One beneficial use of CCBs could be application to agricultural land. Information about the use of one kind of CCB (flue gas desulfurization by‐product, FGD‐BP) on soil is limited. Maize (Zea mays L.) was grown (greenhouse) on an acid soil [Umbric Dystrochrept, pHCa (1:1, soil: 10 mM CaCl2) 4.2] amended with two high CaSO4 FGD‐BPs (5 and 15 g#lbkg‐1 soil) and CaCQ3 (2.5 and 5.0 g#lbkg‐1 soil) at varied calcium/magnesium (Ca/Mg) equivalency ratios (0/0, 1/0, 1/0.01, 1/0.05, 1/0.1, and 1/0.5) to determine treatment effects on growth traits [shoot and root dry matter (DM) and total and specific root length (RL)], mineral concentrations in leaves, and soil pH and electrical conductivity [(EC) 1:1, soil:water]. Magnesium deficiency symptoms were induced on leaves of plants grown with and without low Mg, and the Mg to Ca ratio in each amendment needed to be about 1 to 20 to alleviate Mg deficiency. Shoot and root DM and total RL of plants grown with FGD‐BPs became higher as Mg increased. Specific RL (total RL/root DM, root fineness) was not affected by FGD‐BP and only slightly by Ca/Mg ratio. Shoot concentrations of Mg increased; Ca, phosphorus (P), and manganese (Mn) decreased; and potassium (K), sulfur (S), iron (Fe), zinc (Zn), and copper (Cu) remained relatively constant as amendment and Mg increased. On unamended soil, aluminum (A1) and Mn concentrations in shoots were above normal. Enhancement of growth was closely related to increased soil pH compared to added Mg for CaCO3 amended soil and to increased Mg compared to increased soil pH for FGD‐BP amended soil. Except at the highest level of Mg where soil pH increased, added FGD‐BPs and Mg had only limited effect on increasing soil pH. Soil EC increased from added FGD‐BPs but not from added Mg, and EC was not sufficiently high to be detrimental to plants. Maize grown on this acid soil amended with FGD‐BPs received benefits when caution was used to alleviate mineral deficiencies/toxicities inherent in the soil.  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.
在云南省玉溪市华宁南盘江低热河谷区、华宁山地丘陵区、元江干热河谷区和新平山地丘陵区4个柑桔主产区,选取一个月内未施肥的101个代表性柑桔园采集土壤进行分析。结果表明,玉溪柑桔园土壤pH值变幅在3.98～8.07之间,52.48%土壤pH基本适宜柑桔生长,14.85%土壤pH适宜柑桔生长;土壤有机质匮乏,59.40%土壤低于15g/kg;土壤碱解N,有效P、K、Ca、Mg、Fe、Mn、Zn、Cu、B的平均含量分别为78.64 mg/kg、53.95mg/kg、273.15 mg/kg、3240.37mg/kg、233.39 mg/kg、23.21 mg/kg、43.82 mg/kg、5.67mg/kg、2.89mg/kg、0.50mg/kg。总体上,土壤碱解N和有效B含量不足(低量或缺乏),不足比例分别为78.22%和66.34%;有效K、Ca、Mn和Cu含量超标(高量或过量)居多,超标比例分别为64.36%、51.48%、56.44%和83.17%;有效P、Fe、Zn含量丰富(适宜、高量或过量)为主,丰富比例分别为67.31%、75.24%和88.12%;有效Mg不足、适宜和超标果园则各占约1/3。桔园土壤养分状况的区域特征方面,华宁优于新平,新平优于元江。土壤pH与土壤有效Ca、Mg的正相关性极显著,与有效Mn、Cu的负相关性极显著,土壤有机质与土壤大部分养分正相关且达到显著水平。玉溪柑桔生产上应注意调节土壤pH值,增施有机肥和N、B肥,适度少施K、P肥,注意Ca、Mn和Cu肥的控制。  相似文献   

16.
The objective of this study was to determine whether or not Ca and P in soils from two forested sites at two different stages of acidification were limiting growth of red oak seedlings. The A and E horizons of a Berks soil from Watershed 4 at the Fernow Experimental Forest (cation exchange buffer range) and a Hazelton/Dekalb soil from Pea Vine Hill in Southwestern Pennsylvania (Al buffer range) were placed in pots and utilized as the growth medium for northern red oak seedlings in a greenhouse environment. Soil water NO3-N, Ca, Mg, and K concentrations were significantly higher (α≤0.05) on the Berks soil. Soil exchangeable P and soil solution TP (total phosphorus) were significantly higher (α≤0.10) on the Hazelton/Dekalb soil. Both soils were amended with bone meal (CaPO4) to determine the effects of Ca and P addition on the growth and nutrient uptake of the seedlings. Height growth of the control red oak seedlings was significantly (α≤0.05) greater on the Berks soil after 45 d, but amendment of Hazelton/Dekalb soil with bone meal eliminated this difference. Bone meal addition to the Hazelton/Dekalb soil resulted in significantly greater (α≤0.05) height growth of red oak seedlings when compared to red oak seedlings grown on unamended Hazelton/Dekalb soil, but did not have a similar effect for red oak seedlings grown on Berks soil. Bone meal addition to Hazelton/Dekalb soil resulted in greater (α≤0.05) concentrations of Ca and Mg in red oak leaves. Unfertilized Berks red oak seedling leaves had significantly higher (α≤0.05) concentrations of Ca and K than their Hazelton/Dekalb counterparts. Al/Ca molar ratios were significantly lower on the Berks soil. Red oak height growth was increased significantly by Ca addition to the Hazelton/Dekalb soil.  相似文献   

17.
  【目的】  长期施磷形成的高磷残留土壤,面临土壤酸化、钙镁离子淋失等问题。本研究采用肥料中常见的螯合剂乙二胺四乙酸 (EDTA) 和柠檬酸,研究其对不同磷含量的石灰性土壤中磷素的活化作用,以期为磷肥减施和土壤残留磷高效利用提供有效途径。  【方法】  供试低磷、高磷和白云石改良土壤取自北京市房山区的石灰性土壤,3种供试土壤的全磷含量依次为0.95、1.90和1.91 g/kg,有效磷含量依次为7.39、160和152 mg/kg。采用室内往复振荡浸提方法,两种浸提剂为EDTA和柠檬酸,低磷土壤浸提剂浓度为0.05 g/L,浸提时间为12 h,高磷土壤和改良土壤浸提剂浓度均为0.5 g/L,浸提时间分别为12 h和1 h。每个土壤样品采用相同方法连续浸提10次,同时以去离子水浸提作为对照。测定了浸提液中磷、钙、镁、铁、铝含量,计算各元素的单次浸提量和累积浸提量。全部浸提后,用蒋顾磷分组法测定了土壤中不同组分磷的含量。  【结果】  EDTA和柠檬酸在低磷土壤中单次磷素浸提量均较低,且累积浸提量之间差异不显著,连续浸提10次后磷素的累积浸提量不及土壤全磷的3%;而在高磷土壤和施入白云石的改良土壤中,柠檬酸和EDTA的单次磷素浸提量为低磷土壤的7～64倍,磷素累积浸提量超过土壤总磷的20%,且柠檬酸处理高于EDTA处理。在低磷土壤中,磷素的累积浸提量仅与铁和铝离子的累积浸提量显著相关,在高磷土壤中,磷素的累积浸提量与钙、镁、铁和铝离子的累积浸提量均显著正相关,且相关系数均在0.78以上,而在白云石改良土壤中,磷素的累积浸提量与铝离子的累积浸提量之间无显著相关关系。进一步分析浸提前后土壤磷素组分变化可知,在低磷土壤中,去离子水、EDTA和柠檬酸经10次浸提后土壤Ca2-P显著增加;在高磷土壤中,EDTA和柠檬酸处理浸提的土壤Ca2-P、Ca8-P较去离子水处理显著降低了16.1%、14.9%和37.1%、5.4%。此外,柠檬酸处理还降低了31.4%的土壤Al-P,EDTA和柠檬酸在改良土壤上对于各组分磷的浸提量与在高磷土壤上相似。  【结论】  在连续浸提的条件下,EDTA 和柠檬酸在低磷土壤上无明显活化磷素的效果,而在高磷土壤上和施入白云石的改良土壤上则可持续浸提出大于总磷量20%的磷素。高磷土壤和改良后土壤中被浸提磷素主要来自Ca2-P和Ca8-P,少部分来自Al-P和Fe-P。  相似文献   

18.
  目的  通过研究不同改土物料对苏打碱土中磷（P）素的吸附、解吸及P素形态的影响,为科学改良苏打碱土提供理论依据。  方法  以东北松嫩平原苏打碱土为研究对象,设置不添加改土物料（CK）和添加有机肥（M）、硫酸铝（Al）、石膏（Ca）、硫酸铝 + 有机肥（Al + M）、石膏 + 有机肥（Ca + M）六个处理,研究了不同改土物料对土壤P素的吸附解吸和P素形态的影响。  结果  有机肥处理会降低苏打碱土对P素的吸附,增加对P素的解吸,其它四个处理均会增加土壤对P素的吸附,降低对P素的解吸,其中以Al和Al + M处理差异较大。不同改土物料处理土壤无机P含量均有不同程度增加,其中M、Ca和Ca + M处理均显著提高了土壤中Ca2-P含量（P < 0.05）,以Ca + M处理增幅最大,达到21.43%;不同改土物料处理均可增加缓效态P（Ca8-P、Al-P和Fe-P）含量,增幅为1.00%-112.03%,其中Ca、Al、Ca + M和Al + M处理均可显著提高Al-P和Ca8-P含量,增幅为66.37% ~ 250.1%和18.06% ~ 74.36%。与Ca处理相比,Ca + M处理显著增加了Ca2-P含量（P < 0.05）,显著降低了Al-P和O-P含量（P < 0.05）。  结论  在苏打碱土中石膏和有机肥配施可减少土壤对P素的吸附,增加土壤有效态P含量,是提高苏打碱土P素有效性的最佳措施。  相似文献   

19.
Abstract

A glasshouse study was conducted to determine effects of lime and Mn applied to three Florida soils on plant Mn, growth, and chlorophyll concentration of ‘Tifway II’ bermudagrass (Cynodon dactylon x Cynodon transvaalensis). Four replications of three lime rates (0, 1000, and 2000 mg CaCO3/kg as dolomite and Ca(OH)2 for Astatula fine sand (Typic Quartzipsamment, hyperthermic, uncoated) and Pompano fine sand (Typic Psammaquent, siliceous, hyperthermic); 0, 2000, and 4000 mg CaCO3/kg as dolomite and Ca(OH)2 for Myakka fine sand (Aeric Haplaquod, sandy siliceous, hyperthermic) and three Mn applications (none, 10 mg Mn/kg as MnSO4, and 5 mg Mn/kg as MnEDTA) were used in a randomized, complete block, factorial design. A wide range of plant Mn concentrations existed across treatments for each soil. Differences in plant Mn concentration did not cause significant differences in growth or chlorophyll concentration. The critical plant Mn concentration was not reached, but it appeared to be below 20 mg Mn kg for bermudagrass. Models for prediction of plant Mn concentration using soil pH and extractable soil Mn (Mehlich I, Mehlich II, DTPA‐TEA) were obtained. The applications of MnSO, and MnEDTA each resulted in increased plant Mn under acidic soil conditions. Neither Mn application resulted in increased plant Mn concentration in grass grown on Pompano fine sand with soil pH values of 7.0 or above.  相似文献   

20.
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   

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