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1.
湖南省柑橘园土壤硫素及施硫效应研究 总被引：1，自引：0，他引：1
为了探明湖南省柑橘园土壤硫素含量丰缺程度和柑橘施硫效应,2000～2004年开展了柑橘园土壤硫素含量调查与田间试验研究。结果表明,湖南省柑橘园020cm土层有效硫含量平均为47.7.mg/kg,低于临界值的占9.9%、潜在缺硫的占17.3%。随着土层加深,有效硫含量逐渐增加、全硫含量依次减少。土壤有效硫的地区分布,020.cm土层,81.3%的调查县中有10.0%～75.0%的柑橘园存在缺硫和潜在缺硫。柑橘叶片全硫含量平均为2.32.g/kg,有27.2%的柑橘园低于临界值。在有效硫含量不同的土壤中,柑橘连续4～5年施硫肥平均增产5.3%～30.0%,4个基点平均增产10.7%。连续施硫肥明显提高了柑橘叶片硫和氮含量,柑橘果皮中硫含量提高、氮含量降低,有利于果实品质的改善。施硫肥的增产优质效应表现为有效硫含量缺乏的土壤潜在缺乏土壤中等和丰富土壤;较长树龄较短树龄。随着施硫肥年数延长,施硫增产优质效应更加明显。 相似文献
2.
安徽省土壤有效硫现状及时空分布 总被引：1，自引：1，他引：1
3.
施氮量和土壤含水量对黑麦草还田红壤氮素矿化的影响 总被引：4，自引：0，他引：4
4.
土壤磷素对作物产量及供磷能力的影响 总被引：10，自引：0，他引：10
多年多点试验研究表明 ,河西走廊地区主要耕地 0～ 2 0cm耕层有效P平均含量 9 9mg/kg ,10mg/kg以下的农田占 5 6 4% ,大于 15mg/kg的占 19 5 % ,90 %的农田施P增产 15 0 %～ 2 6 0 %。作物对土壤磷依存率在氮肥激发条件下为 68 1%～ 85 9% ;无肥条件下 46 1～ 75 8% ,供磷力与土壤磷呈正相关。作物吸收的磷素 14 1%～ 3 1 9%由当季施肥供给 ,磷肥的当季利用率平均为 9 9%～ 17 6%。 相似文献
5.
冬小麦?夏玉米体系磷效率对塿土磷素肥力的响应 总被引：2，自引：2，他引：0
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7.
镉污染中性土壤伴矿景天修复的硫强化及其微生物效应 总被引：2，自引：1，他引：2
田间微区试验研究了施硫(S)处理对中性镉污染农田上伴矿景天镉吸取修复效率、土壤pH、有效态镉(Cd)、有效态硫以及微生物群落变化的影响。结果发现,土壤pH值随时间和硫用量的增加而显著下降,有效态镉和有效态硫随时间和硫用量的增加而显著增加。在360 g/m2硫处理下,伴矿景天地上部镉浓度为70.9 mg/kg,较不施硫对照(38.3 mg/kg)增加85%,耕层土壤全量镉去除率为19.4%,是对照(10.5%)的1.85倍。施硫处理150天后,土壤Thiomonas和Rhodanobacter细菌相对丰度显著高于试验前土壤和对照处理。本试验结果表明,中性土壤施加适量硫磺不仅可显著提高污染土壤中镉的生物有效性,也可通过调节与硫代谢相关的功能微生物,显著增强镉的植物吸取修复效率。 相似文献
8.
施氮及灌溉方式对玉米地土壤硝化潜势及微生物量碳的影响 总被引：2，自引：0，他引：2
研究了不同施氮量及灌溉方式下玉米地土壤的微生物量碳及硝化潜势.结果表明:未施氮肥条件下,喷灌比漫灌土壤平均硝化潜势低0.57～4.77 mg/(kg·d);不同时期喷灌施肥土壤平均硝化潜势变化量为2.18～4.77 mg/(kg·d),幅度较小;而漫灌施肥土壤硝化潜势的变化量为-0.57～28.4 mg/(kg·d),幅度较大.土壤微生物量碳的变化受施肥与灌溉方式的影响,9月份土壤微生物量碳均低于7月份,未施氮肥条件下,喷灌下降9.05 mg/kg,变化幅度较小;而漫灌下降176.52 mg/kg,变化幅度较大.施氮肥均降低土壤微生物碳量;不同时期漫灌施肥与漫灌未施肥、喷灌施肥与喷灌未施肥相比分别降低土壤平均微生物量碳108.78～0.57 mg/kg,58.82～86.71 mg/kg. 相似文献
9.
安康耕地土壤速效钾现状与钾肥效应 总被引：6，自引：0，他引：6
土壤普查14年后,安康川道和中高山区作物出现缺钾症面积不断增大.对此,我们对全市不同区域耕地土壤进行了调查分析,结果表明:土壤速效钾与土查时相比,平均下降37.06mg/kg,水稻土下降32.27mg/kg,旱地土壤下降34.5mg/kg;速效钾<100mg/kg的水田占60.68%,旱地占59.59%,川道占78%,中高山(镇坪、平利)占96.43%;土壤钾素下降趋势是中高山>川道>丘陵.钾肥试验表明:施1kgK2O,水稻、小麦、玉米、薯类、油菜分别平均增产13.83,8.1,26 相似文献
10.
《植物营养与肥料学报》2018,(6)
【目的】研究鴥土区冬小麦-夏玉米轮作体系磷肥利用效率(PUE)和土壤肥力(磷素)的关系,可以界定土壤磷素的最佳管理范围及合理施磷量,为实现作物高产和减少磷素损失提供理论依据。【方法】采取鴥土长期定位试验5个不同磷素水平的土壤,有效磷含量依次为3.90 (F1)、15.00 (F2)、23.60 (F3)、35.70 (F4)和50.00(F5) mg/kg进行盆栽试验,供试作物为小麦‘小偃22’和玉米‘郑单958’。每个磷素水平土壤上设置5个施磷量(P2O5 0、30、60、90、120 kg/hm~2)。作物成熟后,收获地上部所有植株,晒干、脱粒后测定地上部生物量、籽粒产量,籽粒和秸秆样品粉碎后测定其含磷量。作物收获后均匀采集盆内土样约50 g/盆,风干并混匀后分别过1 mm和0.15 mm筛,测定土壤速效磷和全磷含量。计算冬小麦-夏玉米种植体系磷肥利用效率与土壤磷素水平的关系。【结果】F1土壤增施磷肥可显著提高小麦和玉米的籽粒产量,与P0相比,所有施磷处理小麦增产52.2%～119.7%、玉米增产94.7%～212.7%;F2、F3、F4和F5土壤磷肥增产效果不显著。经过两季作物种植,与P0相比,F2土壤施磷60 kg/hm~2、120 kg/hm~2和F5土壤施磷120 kg/hm~2显著提高了全磷含量,其他磷水平土壤全磷含量无显著变化;F1、F2、F3、F4和F5土壤施磷处理的土壤速效磷含量分别增加了-4.08%～434.69%、26.49%～112.77%、6.74%～48.24%、4.07%～43.65%和-4.84%～28.29%。冬小麦磷肥利用效率(PUE)与土壤Olsen-P之间呈显著的正相关关系(P 0.05),P30、P60、P90和P120线性关系决定系数分别达到0.996、0.899、0.760和0.820。夏玉米PUE在P30下随土壤磷素水平的提高呈二次抛物线形式增加,据此可得出在Olsen-P为12.32 mg/kg时PUE达到100%,当土壤速效磷为33.63 mg/kg时PUE达到最大值155.24%;在P60、P90和P120时,PUE随土壤Olsen-P含量上升而直线增加,Olsen-P分别达到12.22 mg/kg、16.64 mg/kg和14.39 mg/kg后维持在一个水平。整个冬小麦-夏玉米体系PUE随土壤速效磷的变化趋势和夏玉米类似,冬小麦(P30)和夏玉米(P30)总施磷量为P2O5 60 kg/hm~2时,可算出土壤速效磷为17.97 mg/kg时PUE达到100%;当速效磷达到40.11 mg/kg时,PUE达到最大值131.51%。在同一磷素水平土壤上,随施磷量增加,小麦和玉米PUE均显著降低,尤其是施磷量高于60 kg/hm~2后。【结论】关中鴥土区冬小麦-夏玉米体系,小麦季土壤速效磷应大致控制在17～40 mg/kg范围内,玉米季土壤速效磷控制在13～34 mg/kg范围内进行管理;整个冬小麦-夏玉米体系将土壤速效磷大概控制在17～40 mg/kg范围内,总推荐施磷量为P2O5 60～120 kg/hm~2为宜。 相似文献
11.
The effect of elemental sulphur (S) and S containing waste applications on soil pH treated with 0–2,000 kg ha‐l elemental S, and 0–100 tons ha‐1 of waste was determined in the field and the pots. Sorghum (Sorghum bicolor L.) was grown in a Lithic Xerorthent soil which was taken from where the field experiment was conducted in pots receiving 5 kg soil. Plants were harvested 20 weeks after planting or 30 weeks after the applications for determination of dry matter yield and phosphorus (P), iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) uptake by shoots. EC, NaHCO3‐extractable P, and DTPA‐extractable Fe, Zn, Mn, Cu also were measured in pot soil at the 5th, 10th, and 30th weeks. All treatments led to a decrease in soil pH though pH tended to increase again during course of time in both field and pot experiments. The both elemental S and waste applications in pot experiment caused an increase in dry matter yield and P, Fe, zinc (Zn), Mn and Cu uptake (mg pot‐1) by shoots in sorghum plant. There was also an increase in EC of soil due to both applications of S. The concentration of available P extracted by NaHCO3 in the pot soil, though not significantly different, was slightly higher compared with the control. Waste applications increased DTPA‐extractable Fe content of the soil, DTPA‐extractable Mn and DTPA‐extractable Cu. DTPA‐extractable Zn content, however, was reduced by the same applications. 相似文献
12.
The critical S concentration and S requirement of the soil microbial biomass of a granitic regosol was examined. S was applied
at the rate of 0, 5, 10, 20, 30 and 50 μg S as MgSO4·7H2O, together with either 3000 μg glucose-C or 3333 μg cellulose-C, 400 μg N, and 200 μg P g –1 soil and 200 μg K g–1 soil. Microbial biomass, inorganic SO4
2–-S, and CO2 emission were monitored over 30 days during incubation at 25 °C. Both glucose and cellulose decomposition rates responded
positively to the S made available for microbial cell synthesis. The amounts of microbial biomass C and S increased with the
level of applied S up to 10 μg S g–1 soil and 30 μg S g–1 soil in the glucose- and cellulose-amended soil, respectively, and then declined. Incorporated S was found to be concentrated
within the microbial biomass or partially transformed into soil organic matter. The concentration of S in the microbial biomass
was higher in the cellulose- (4.8–14.2 mg g–1) than in the glucose-amended soil (3.7–10.9 mg g–1). The microbial biomass C:S ratio was higher in the glucose- (46–142 : 1) than in the cellulose-amended soil (36–115 : 1).
The critical S concentration in the microbial biomass (defined as that required to achieve 80% of the maximum synthesis of
microbial biomass C) was estimated to be 5.1 mg g–1 in the glucose- and 10.9 mg g–1 in the cellulose-amended soil. The minimum requirement of SO4
2–-S for microbial biomass formation was estimated to be 11 μg S g–1 soil and 21 μg S g–1 soil for glucose- and cellulose-amended soil, respectively. The highest levels of activity of the microbial biomass were
observed at the SO4
2–-S concentrations of 14 μg S g–1 soil and 17 μg S g–1 soil, for the glucose and cellulose amendments, respectively, and were approximately 31–54% higher during glucose than cellulose
decomposition.
Received: 20 October 1999 相似文献
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14.
《Soil biology & biochemistry》1986,18(2):131-140
In anaerobic peat, SO42− is reduced to H2S, some of which is recovered in this form during refluxing under N2 (steam-volatile H2S), while the remainder is incorporated into the organic matrix. Inhibition of SO42− metabolism by SeO42− and MoO42−, and stimulation by H2, suggest that the reduction is caused by dissimilatory sulphate-reducing bacteria. The abundance of Fe in the profile, together with the instability of FeS to heat, indicate that this compound may represent the dominant component of the steam-volatile H2S pool, although some H2S from heat-labile organic S may also be released. Humic substances which were soluble in 0.5 M NaOH accounted for > 40% of 35S incorporated into organic matter from H235S. H235S reacted by non-biological processes with isolated humic acid suspended in acetate buffer solution (pH 4.5) and resulted in extensive labelling of humic material of mol. wt > 104. 相似文献
15.
江西省雨水、灌溉水及渗漏水中的硫对土壤硫的影响 总被引：1，自引：0，他引：1
Ten rainfall and irrigation water-collecting posts were set up in different ecotype districts of Jiangxi Province,China,to quarterly measure S content in rainfall and irrgation water.A rasinwater chemical composition-collecting device was used to collect the sulphur in rainfall,and the amount of sulphur adsorbed on the resin column in the device was determined.The soil percolating water was gathered using 6 lysimeters built up according to the profile sequence of the red soil derived from red sandstone and the red soil derived from Quaternary red clay,separately.On the lysimeters peanuts,soybean and radish were grown in rotation.Two treatments were designed:without S addition and with S additin at a rate of 14kg S ha^-1,The SO4^2- contents in rainfall,irrigation water and soil percolating water were determined by the turbidimetry.The results in 1997 showed that the average annual S content in rainwater ws 28.13kg S ha^-1.the average S content in irrigation water was 1.7mg S L^-1,and the average content of SO4^2- in soil percolation water was 2.30kg Sha^-1 year^-1 and 4.70 kg Sha^-1 year^-1 in treatments without and with sulphur application,respectively,In Jiangxi Province,apart from the losses by runoff and leaching,the sulphur in rainfall avaliable to crops is 7.3kg S ha^-1 year^-1 and additional S application is required.When rice is grown.however,irrigation water can suply 6.9kg S ha^-1,which,along with the sulphur in rainfall,cal almost meet the S requirement of one cropping of rice. 相似文献
16.
F. J. Zhao P. E. Bilsborrow E. J. Evans S. P. McGrath 《Journal of plant nutrition》2013,36(4-5):549-558
This study investigated the variation of nitrogen to sulphur ratios in rapeseed (N/S)t and in rapeseed protein (N/S). Under S‐sufficient conditions the (N/ S)t ratios varied considerably between different varieties, with low glucosinolate varieties having higher ratios than high glucosinolate varieties. In contrast, (N/S)p remained relatively constant at about 11.5 for all varieties tested, though significant effects of N and S nutrition on the (N/S) ratio were present. The ratio increased in the S‐deficient samples. Results of yield responses to S fertilizer and (N/S)(from six field experiments were used to see if (N/S)t could indicate the S status of the crop. Although yield losses due to S shortage tended to occur when (N/S)t was greater than 10, the relationship was not sufficiently reliable for use in diagnosis. 相似文献
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18.
《Communications in Soil Science and Plant Analysis》2012,43(9-10):1315-1328
Abstract Upland pastures on coarse‐textured sulphur (S)‐deficient soils in moderate to high rainfall areas may benefit from S fertilization using elemental S to avoid leaching losses. Two grades of elemental S, 120 and 300 mesh, were assessed as a source of S for grass and clover. In laboratory incubations using an upland soil at 7 and 14°C, oxidation of the 120 mesh S was very slow while 65% of the 300 mesh S was oxidized after 48 days at 14°C. In pot trials of ryegrass in a lowland soil and of ryegrass and clover in the upland soil both elemental S grades gave satisfactory yield increases which were not significantly different from applying potassium sulphate. High ambient temperatures during the pot experiment probably ensured an adequate oxidation rate of both elemental S grades. High application rates of the potassium sulphate gave rise to luxury consumption while very high rates of elemental S (equivalent to 200 kg S ha‐1) showed some toxicity. Application of a previously‐described model of S oxidation confirmed the importance of soil temperature in controlling S oxidation rates. 相似文献
19.
The significance of microbial biomass sulphur in soil 总被引：2，自引：0，他引：2
The soil microbial biomass S fraction of total organic S in soil is considered to be relatively labile and the most active S pool for S turnover in soil. Its significance has been demonstrated in studies of S deficiency in agronomic situations and in those of S pollution from high atmospheric inputs. The utility of the CHCl3 fumigation-extraction technique for the measurement of microbial S has been proved for a range of soils and conditions. The various methodologies currently available are discussed, including the need for determination of the conversion (K
s) factor. Microbial S values, summarized from the available literature, ranged from 3 to 300 g S g-1 dry weight soil. They were generally greater in grassland than in arable systems, though the greatest values were obtained in the few examples from forest and peatland soil systems. Microbial S values showed direct relationships with both microbial C and with total soil organic S. Again, there were significant differences between arable and grassland systems. The effect of factors such as organic and inorganic inputs as well as soil physical conditions on microbial S are described. Microbial S turnover rates were estimated from seasonal, 35S-labelling and modelling studies. These rates varied between an approximately annual turnover rate in undisturbed soils up to 80 year-1 following the addition of readily available substrates. Prospective future research areas are also outlined. 相似文献