氮磷钾肥料在土壤中转化过程的交互作用 Ⅱ.硫酸铵在水稻土中的转化

通过室内培养实验,研究了Ca(H2PO4)2和KCl对(NH4)2SO4在土壤中转化的影响。结果表明,Ca(H2PO4)2对(NH4)2SO4转化的影响较小。Ca(H2PO4)2对未施氮土壤中硝化作用的正效应,以及对施氮培养前期土壤中硝化作用的负效应可能与土壤pH的变化有关。施用KCl显著影响供试水稻土中(NH4)2SO4的转化,主要表现为:(1)施钾导致培养初期土壤中水溶性铵的增加与交换态铵的减少,与铵钾的代换作用有关,培养后期这两种形态铵的共同增加则与钾抑制硝化作用有关。(2)施钾既显著地抑制了氯化钠提取过程中土壤铵的释放,也抑制了培养过程中土壤固定态铵的释放。施钾对风干土样水溶性铵的影响与鲜样中不同,也与施钾抑制土壤风干过程中铵的释放有关。(3)钾铵同时施用,施钾促进了铵的固定。(4)施钾显著抑制了硝化作用,本文实验条件下,其直接作用机制可能并不是钾抑制了土壤中固定态铵的释放。单施钾肥会显著降低未施氮土壤中无机氮的有效性。由以上结果推测,氮钾肥配施将不仅有利于减少硝态氮的淋洗和反硝化脱氮作用,而且可增强土壤中铵的缓冲能力。这也表明土壤中钾对铵态氮肥转化的影响,可能是生产实践中氮钾肥配合施用可提高氮肥利用率的原因之一。     

土壤pH与烤烟钾素营养关系的研究

选择代表性的贵州植烟土壤,施石灰提高ｐＨ,施硫酸亚铁和硫磺粉降低ｐＨ,通过两年烤烟盆栽试验,研究了土壤ｐＨ对烤烟钾营养状况的影响。结果表明：土壤ｐＨ平均为５．３３和６．１时烟叶产量较高;超出此ｐＨ范围,产量有下降趋势;ｐＨ低于５．０产量急剧下降．烟叶吸钾状况及施钾效果均以土壤平均ｐＨ５．３３的最高;ｐＨ低于５．０及高于６．１对烟株的钾素营养都有不同程度的影响,以低ｐＨ对钾吸收的抑制作用最大。初步提     

华北旱地土壤硫施用量指标

Fifteen upland soils collected from the major arable areas in North China were used to assess the availability of soil sulfur (S) to plants in a pot experiment. Soils were extracted with various reagents and the extractable S was determined using turbidimetric method or inductively coupled plasma atomic emission spectrometry (ICP-AES), respectively. In addition, mineralizable organic S, organic S, N/S ratio, sulfur availability index (SAI) and available sulfur correction value (ASC) in soils were also determined. The S amount extracted by 1.5 g L^-1 CaCl₂ was nearly equivalent to that by 0.25 mol L^-1 KCl (40 ℃), and both of them were slightly smaller than that by 0.01 mol L^-1 Ca(H₂PO₄)₂ solution, as measured by turbidimetric method or ICP-AES. The extractable S measured by turbidimetric method was consistently smaller than that by ICP-AES. All methods tested except that for organic S and N/S ratio produced satisfactory results in the regression analyses of the relationships between the amounts of S extracted and plant dry matter weight and S uptake in the pot experiment. In general, 0.01 mol L^-1 Ca(H₂PO₄)₂-extracted S determined by ICP-AES or turbidimetric method and 0.25 mol L^-1 KCl (40 ℃)-extracted S determined by ICP-AES appeared to be the best indicators for evaluation of soil available S.     

冲积潮土镁的释放特征及相对植物有效性

Experiments including two in laboratory and one in greenhouse were carried out to study non-exchangeable magnesium release from fluvo-aquic soils sampled from Daxing and Changping counties located in the suburbs of Beijing and Mg relative availability of the two soils to plants.In a batch experiment in labortory the soils were incubated under wet conditions and alternation of dry and wet conditions and determined for amount of Mg relesed at the 4th,8th and 12th week,respectively,after extraction of exchangeable Mg with 1molL^-1 NH4Ac.The amount of Mg released from the soil of Daxing was higher than from the soil of Changping,which was in accordance with the fact that the soil of Daxing had higher contents of all forms of Mg than that of Changping.There was little difference in Mg release from soils between wet conditions and alternation of dry and wet conditions.About 1%-2% of the total non-exchangeable Mg might be released within 12 weeks of incubation.restoring about 30%-35% of the original soil exchangeable Mg.Results of the experiment on kinetics of Mg release from the soils through continuous extractions with 0.5molL^-1 NH4Ac(pH7.0) on a continuous flow apparatus in laboratory showed that Mg released rapidly in the beginning,decreased sharply with time and kept stable at 60 and 240 min for the soile of Changping and Daxing,respectively,Among the five mathematical models used to describe the kinetics of Mg release,the parabolic diffusion equation best fitted the cumulative Mg release,indicating that diffusion of Mg out of the soils might be the controlling processa.The experiment of exhaustive cropping with 1 crop of tomato(Lycopersicon esculentum Mill.) followed by six crops of corn(Zea mays L.)in greenhouse showed that soil exchangeable Mg decreased remarkably with cropping .After three crops,the percentage of the total plant Mg uptake that came from soil non-exchangeable Mg was 29.5% for the soil from Changping and 35% for the soil from Daxing,About 50% of the total Mg uptake by plants in the six crops was believed to come from the soil non-exchangeable Mg form.     

pH和磷的交互作用对稳定化土壤砷释放的影响

以3种含Fe材料稳定化土壤(FeSO_4、FeS和Fe~0稳定化土壤)为研究对象,研究了不同pH和P的交互作用对As释放量的影响及其作用机理。结果表明,在pH=3条件下,随着时间的延长能够促进释放的As重新趋于稳定化,而pH=11时3种稳定化土壤中As的释放量显著增加,144 h后分别约为pH=3时的10.5、16和10倍。添加P时,在3种pH条件下都促进了稳定化土壤中As的释放,尤其在酸性条件下,相对于无P体系As的释放量增加最为明显。FeSO_4稳定化土壤中As的释放特征能用Elovich方程较好地描述,而双常数方程拟合FeS和Fe~0稳定化土壤效果更优。在pH=3条件下,3种稳定化土壤中As的释放量与Ca、Mg、Mn的溶出量呈(极)显著相关,而pH=11时FeSO_4和FeS稳定化土壤中As的释放量与SO_4~(2–)的溶出量呈(极)显著相关,表明在酸性条件下,稳定化土壤As的释放主要受Ca、Mg、Mn氧化物结合态As溶解的影响,而碱性条件下,FeSO_4和FeS稳定化土壤中As的释放可能与硫化物的溶解有关。     

中国江西红黄壤地区湿地松幼苗(pinus elliottii engelm.)对氮磷钾肥的生长反应

During 1991-1995,the growth responses of young slash pine to N,P and K fertilizers and rational rate and ration of fertilizer in yellow-red soil at Fengshushan Forest Farm Jiangxi Province were studied.N fertilizer decreased the growth of slash pine,while P no only significanlty improved the increment of bottom diameter,height and crown diameter,but also caused earlier canopy closure of the stand.It also had a sustainable effect in the next two years.Slash pine had the most significant response to the treatment of 200 kg P2O5 ha^-1 ,in which tree height,bottom diameter and crown diameter(EW and SN) were increased by 22%,35%,20% and 18% i 1994,21%,25%,10% and 10% in 1995,respectively,compared to the control.Although there was no remarkable response to K fertilizer,good growth response to the application of 100 kg P2O5 plus 100 kg K2O ha^-1 existed and tree hieght ,bottom diameter and rown diameter(EW and SN ) were increased by 31%,14%,23% and 21%,respectively,in 1993 ,compared to the control.     

土壤酶活性影响因子的研究——Ⅰ.有机肥料对土壤中酶活性及氮磷转化的影响

本文研究了黄淮海平原广泛应用的秸秆肥、牲畜粪、堆肥和其他有机肥料的酶活性。在供试材料中,秸秆肥的蔗糖酶和淀粉酶活性较其他有机肥料的强:蔗糖酶活性在500毫克葡萄糖/克以上,淀粉酶活性15毫克麦芽糖/克以上。除个别例外,牲畜粪的脲酶活性较其他有机肥料的强,酶活性在18毫克NH₃-N/克以上;其蛋白酶活性也比其他有机肥料的强。大豆秸肥是供试材料中酶活性状况最好的有机肥料。塘泥的酶活性较其他有机肥料的低。蚯蚓排泄物不仅具有较强的蔗糖酶和磷酸酶活性,而且也有一定的淀粉酶、脲酶和蛋白酶活性。在实验室条件下,用秸秆粉和牲畜粪处理土壤,能不同程度的增强其蔗糖酶、磷酸酶和脲酶话性。田间试验表明,施高量麦秸肥的潮土脲酶和磷酸酶活性较强,施低量的则较弱。有机肥料不仅能增强土壤酶活性,而且对土壤有效氮、磷的转化起重要作用。     

pH变化条件下针铁矿表面吸附的磷酸盐联合态的转化

X-ray photoelectron spectroscopy(XPS) and automatic titrimeter were used to study the relation bewteen pH and the transformation of the coordinate forms of P on goethite surfaces.The results showed that for a given P concentration,increasing the pH of suspension could cause a fast transformation of monodentate complexes of phosphate ions on goethite surfaces to binuclear ones,When lowering the pH,additional adsorption of P occurred and the binuclear complexes reverted slowly to the monodentate ones,The dissociation and association of protons of the sorbed P caused by pH changes was considered to be a major reason leading to the transformation of the coordinate forms of P on the surfaces.The stability of binuclear surface complex of P was greater than that of monodentate omplex.The possible reactions on the interface of goethite and solutions with pH changes,and the reasons causing the different stabilities of the two coordinate P complexes are discussed in the paper.     

不同肥料配施对土壤主要养分含量及作物氮、磷、钾表观利用率的影响

四年的分析结果表明，氮磷钾化肥配施有机肥和秸秆可明显提高土壤有机质，全氮、碱解氮，速效磷和速效钾含量，氮磷钾三元素化肥配施可明显提高土壤氮、磷、钾的含量和供给能力，单一施氮和氮，磷、钾三元素中的两两配合施入，可较明显地提高该配合所含养分在土壤中的含量，四年的分析结果还表明，含氮磷钾三元素配施的各处理总体上利用率较高。     

土壤pH值和含水量对土壤硝化抑制剂效果的影响

硝化抑制剂如2-氯-6-三氯甲基吡nitrapyrin,通常与氮肥配施来抑制硝化作用提高农田中肥料的利用率,但是其抑制效果会受到土壤理化性质的影响。采用新工艺重新合成后的新型nitrapyrin纯度高达98%,由于杂质减少而具有更好的硝化抑制效果。为了研究土壤pH值和含水量对新型nitrapyrin抑制效果的影响,明确nitrapyrin适合施用的土壤条件,采用室内培养试验,研究了在不同的土壤pH值和含水量下nitrapyrin对无机氮含量动态变化和硝化作用强度的影响,以及其硝化抑制率的变化规律。结果表明:随着土壤pH值的升高,铵态氮含量降低,硝态氮含量和表观硝化率呈现上升的趋势,并且在所有pH值处理下氮肥配施nitrapyrin均显著地降低了矿质氮库铵态氮的转化量,均不同程度地抑制了硝化作用;在培养的第9天,nitrapyrin在pH值7.70处理下对硝化作用抑制效果最好,硝化抑制率达到91.53%,但硝化抑制率的降低速率在高pH值处理上更快;在培养的第45天,当pH值为4.66时,硝化抑制率为36.43%,显著高于其他处理;在整个培养过程中,施用nitrapyrin能显著抑制各处理的硝化作用,硝化抑制率在不同土壤含水量上的表现为:40%WHC60%WHC80%WHC。可见,nitrapyrin更加适合施用在酸性土壤以及旱地土壤上,该研究可以为新型硝化抑制剂nitrapyrin在农田中施用的最优条件提供理论依据。     

Effects of Carbofuran on Availability of Macronutrients and Growth of Tomato Plants in Natural Soils and Soils Amended with Inorganic Fertilizers and Vermicompost

The effects of lower field rate (LFR), field rate (FR), and higher field rate (HFR) applications of carbofuran on ammonium (NH₄)-nitrogen (N), nitrate (NO₃)-N, available phosphorus (P), and available potassium (K) contents in natural soils and those amended with inorganic fertilizers and vermicompost on the growth of tomato plants were studied. The NH₄-N, NO₃-N, available P, and available K contents increased up to FR but the most significant increase in was observed at LFR of carbofuran application. At HFR there was a significant reduction in nutrient availability. With passage of time all these parameters increase up to 30 days; thereafter, a decrease was observed up to the end of the experiment in both unamended and amended soils. The greater plant growth was observed at LFR of carbofuran application and at HFR the plants exhibited phytotoxicity in the form of marginal leaf scorching in both systems. The morphological growth parameters of tomato plants were positively correlated with nutrients availability.     

酸性和中性水田土壤施用硅肥的效应研究 Ⅰ.对土壤pH、Eh及硅动态的影响

分别选取酸性和中性水田土壤进行盆栽试验,研究施用硅肥对水稻各生育期土壤溶液pH、Eh及硅浓度的影响。结果表明,淹水种稻后酸性土壤pH迅速升高,而中性土壤pH降低,然后均趋于中性;Eh的变化基本均呈近似＂W＂形;土壤溶液硅浓度则经历了一个先升高后下降并趋于稳定的变化过程。与对照相比,单施高炉渣或高炉渣与葡萄糖配施处理在提高土壤溶液pH和Eh、增加硅浓度方面的效果较为明显,尤其在酸性水田土壤上表现得更为突出;偏硅酸钠的施用效果只是在水稻生长的某一时期在中性水田土壤上表现得相对明显;单施葡萄糖会降低土壤Eh,提高生育前期土壤溶液中的硅浓度。在水稻全生育期内,高炉渣与葡萄糖配施处理的土壤溶液中硅浓度升高的幅度最大,在酸性水田土壤和中性水田土壤上分别是对照处理的1.40（最小倍数）~4.93（最大倍数）倍和1.19（最小倍数）~2.72倍（最大倍数）,说明施用高炉渣硅肥,可明显提高土壤硅素供应水平,对促进水稻生长、提高水稻产量有重要意义。     

土壤中可溶性氮和pH对有机肥和化肥的短期响应

通过温室盆栽试验,施用猪粪堆肥(PC)、污泥堆肥(SC)、菜籽饼肥(CM)和无机化肥(IF)后,对土壤pH值和不同形态氮素的短期响应进行研究,探讨土壤可溶性无机氮、有机氮及土壤pH值之间的相互关系。结果表明,CM,PC和IF处理的pH值都呈现先快速下降后缓慢回升的趋势,但PC处理下降幅度较小;而SC处理和不施肥对照(CK)处理的pH值基本不变;不同施肥处理均提高了土壤中氮素水平,3种有机肥中以CM处理最显著地提高了土壤中总可溶性氮(TDN)、NH4+-N、NO3--N和可溶性有机氮(DON)浓度,PC处理的次之,SC处理的最弱,而IF处理与CM处理提高幅度相似。不同施肥处理中土壤可溶性氮表现出不同的短期响应,IF处理和CM处理的TDN分别经过11,13d的稳定期后迅速上升到一个较高的水平,至31d开始下降;PC处理和SC处理未出现突然升高的现象,而是前20d较稳定在一定的范围内波动,之后缓慢下降,总体与对照趋势一致。不同处理土壤中NH4+-N均呈下降趋势;IF处理、CM处理的NO3--N呈增加趋势,PC处理的呈先增加后降低趋势,而SC处理的呈缓慢下降趋势,结果说明不同有机肥在土壤中的转化存在明显的差异。相关性分析显示,CM处理、IF处理的土壤pH值与NH4+-N呈极显著正相关,而与NO3--N呈极显著负相关;除PC处理外,其他处理的DON含量与TDN具有显著正相关性,而PC处理的DON同时与NH4+-N、NO3--N呈显著负相关。     

Response of corn to NPK fertilization grown in a Latosol in South Sulawesi,Indonesia

Abstract

Corn (Zea mays L.) is next to rice as an important food crop grown in South Sulawesi, Indonesia. However, yields obtained by farmers are rather low, around 0.6 to 1.0 ton/ha. Efforts to increase yield have been tried through the application of NPK fertilizers. A study was conducted to determine the effects of N, P and K application on corn yield and what soil constrains, in terms of nutrient elements in the corn plants, exist in the latsols found at Desa Tokka, Sinjai, and South Sulawesi. It was found that application of K significantly increased the growth and corn grain yields on the latosols at Sinjai. Without K, grain yield and the K content in the ear leaf were low. The correlation between grain yield and rate of K shows that an application of 72 kg K₂O/ha together with 90 kg N and 80 kg P₂O₅ per ha produce the best yield of 3.6 tons/ha. The K content in the ear leaf of 1.8% was related to this maximum yield.     

外源钾对三种不同土壤钾转化影响的研究

采用盆栽试验,在黄棕壤,砖红壤,黑土三种土壤上种植烟草,研究了外源钾对土壤中钾转化的影响,结果表明:在黄棕壤,黑土上,0.0-0.8 g kg-1施肥范围内,随着施钾量的增加,土壤中速效钾和缓效钾的总增量、作物的含钾量均在增加,尤其是在0.8 g kg-1施肥水平时,二者超出了施肥的增加量,说明施钾促进了其它钾的释放;三种土壤中粘土矿物含量为:黑土>黄棕壤>砖红壤。     

参与碳氮磷转化的水解酶对不同施肥响应的差异

本文旨在研究土壤水解酶对不同施肥的响应差异以及影响因素。通过在红壤中添加牛粪有机肥、化肥进行90d的室内土壤培养试验,采用微孔板荧光法动态分析5、30和90d参与碳氮磷转化的土壤水解酶(α-1,4-葡萄糖苷酶、β-1,4-葡萄糖苷酶、纤维素酶、木聚糖酶、亮氨酸氨基肽酶、β-1,4-N-乙酰氨基葡萄糖苷酶、磷酸酶)活性。与不施肥(对照)相比,在30 d后,化肥处理的总酶活性显著下降,对应的参与碳氮磷转化酶活性均有不同程度下降;而有机肥处理的总酶活性在培养期内均未发生显著变化,但是其α-1,4-葡萄糖苷酶显著增加,而磷酸酶活性显著降低。参与碳转化的4种水解酶中,只有α-1,4-葡萄糖苷酶活性对施肥的响应较强,且施加有机肥增加其活性而无机肥则降低其活性;对于参与氮转化的水解酶而言,化肥明显抑制了亮氨酸氨基肽酶活性,而有机肥增加了β-1,4-N-乙酰氨基葡萄糖苷酶活性;磷酸酶活性明显受到有机肥的抑制作用,而对化肥的响应总体不明显。不同水解酶对不同施肥的响应有明显差异,NMDS分析表明,α-1,4-葡萄糖苷酶和亮氨酸氨基肽酶响应最明显,其次为磷酸酶与木聚糖酶;相关和冗余分析显示,土壤p H、可溶...     

Nitrogen Mineralization and Nitrification in Two Soils with Different pH Levels

ABSTRACT

Soil pH is one of the properties that mostly influences nitrification rates, and can be used as a tool for controlling this process, seen that depending on its extent it may lead to nitrogen (N) losses and subsequent contaminations. The aims of this study were to evaluate mineralization and nitrification of two soils at different pH levels. The experimental design was factorial with two factors and three replicates, with the first factor referring to two samples of red latosols, one eutrophic (LV1) and the other dystrophic (LV2), and the second factor was soil’s pH, at six levels: 4.0, 4.5, 5.0, 5.5, 6.0, and 6.5. Samples were incubated for 70 days in laboratory conditions. Both nitrate (N-NO₃) and mineral N contents were determined and adjusted to growth models. The eutrophic soil presented higher mineral N and N-NO₃, and the increase of pH levels led to increases of both inorganic N and N-NO₃contents. Increases in pH levels caused N-NO₃levels to increase in both soils, however this occurrence happened because it increased the amount of mineralized N in the soil, seen that in all pH ranges in both soils practically all mineral N was in the form of N-NO₃.     

Application of Excess Nitrogen,Phosphorus, and Potassium Fertilizers Leads to Lowering of Grain Iron Content in High-Yielding Tropical Rice

Influences of nitrogen (N), phosphorus (P), and potassium (K) fertilizer doses were assessed on iron (Fe) accumulation in leaves and grains of three high-yielding rice cultivars differing in grain Fe concentration. Effects of these treatments were also measured on grain yield, leaf area, and plant biomass of the cultivars. Nitrogen, P, and K applications improved plant biomass and grain yield of all cultivars. Among the nutrients, N was most effective in increasing leaf Fe concentration, followed by P and K in all three rice cultivars. Sharbati accumulated the greatest concentration of leaf Fe followed by IR-64 and Lalat. However, greater doses of these nutrients adversely affected grain yield and Fe content of leaf and grain. Application of excess N, P, and K fertilizers may, thus, sometimes results in lowering of grain Fe content in rice. Judicious application of the elements is recommended for prevention of Fe-induced malnutrition.     

Long-Term Trends of Nitrogen and Phosphorus Use and Soil pH Change in Northern Idaho and Eastern Washington

Extension educates growers about using best management practices (BMPs) for nutrient management. However, it is important to understand grower management trends to prepare the best possible educational programs for growers. Three mail-based grower surveys conducted in 1981, 1996, and 2011 were used to document changing nitrogen (N) and phosphorus (P) fertilizer use and soil pH trends in the >450-mm precipitation zone of northern Idaho and eastern Washington, USA. The information collected in this paper spans a 40-year period. Nitrogen application rates have slightly increased, while P application rates on cereal crops have remained constant over the past 40 years. Average soil pH values have declined significantly over this time period; however, only about half of the surveyed growers were aware of this. This study is valuable because it (1) contains important information provided by growers on fertilization trends for the past 40 years (1971 to 2011), (2) quantifies the awareness of growers about soil pH decline in the region, and (3) provides baseline information, which can be used both in educational programming and to compare with future nutrient management.