我们何时需要施用硫肥

本文综合介绍了国内外对硫肥的研究应用善并对四川省土壤有效硫作初步分析,但结合田间试验,即使土壤耕层有效硫处于缺乏范围,增施硫肥对玉米、小犍产量无明显增加。在四川省的空气污染未得到有效控制之前,只要普钙仍为我省主要灰肥品种,四川盆地主要农耕区不会发生大面积土壤 素缺乏问题。』     

耕作方式对紫色水稻土全硫及有效硫的影响

以位于西南大学农业部重庆紫色土生态环境重点野外科学观测试验站 1990 年设立的长期免耕试验田为研究对象,通过采集 0 ~ 60 cm 土壤,应用等质量计算方法,探讨了冬水田平作（DP）、水旱轮作（SH）、垄作免耕（LM）和垄作翻耕（LF）等不同耕作方式对土壤全硫和有效硫的影响。结果表明,在 0 ~ 60 cm 深度内,土壤全硫和有效硫含量呈现出明显的垂直递减规律,即随着土壤深度的增加,含量逐渐降低;不同耕作方式下,土壤全硫含量及储量为 LM＞SH＞DP＞LF,有效硫含量及储量为 LM＞DP＞LF＞SH。长期垄作免耕提高了土壤全硫及有效硫的含量和储量,与对照 DP 处理相比,LM 处理全硫与有效硫含量分别增加了 20.80% 和 1.31%,储量分别增加了 19.54% 和 5.36%。耕作层（0 ~ 20 cm）,DP、SH、LM、LF 处理土壤有效硫平均含量分别为 27.15、13.45、31.43 和 24.01 mg/kg,DP、LF 以及 LM 处理为硫不缺或硫丰足,而 SH 处理为缺硫土壤（土壤有效硫含量＜16 mg/kg）。对缺硫土壤,应重视硫肥的施用,以促进农作物产量和品质的提高。     

安徽省土壤有效硫现状及时空分布

【目的】 土壤有效硫是作物硫素营养的主要来源,在获取省域范围耕地土壤有效硫基础数据和硫肥试验研究结果的基础上,以地统计学特征分析和新的土壤有效硫分级指标统计为手段,研究全省土壤有效硫时空变化特点和区域性分布现状,掌握全省耕地土壤硫养分丰缺状况及供给水平,为科学施肥提供依据。 【方法】 选择安徽省砂姜黑土、潮土、黄褐土、水稻土等11个土类,采集农田0—20 cm耕层土样34.5万个。通过大样本数据的统计分析,利用ArcGIS进行Kriging插值的地统计学分析,按照本省耕地土壤有效硫新的丰缺分级标准,即极缺 (< 10.0 mg/kg)、缺乏 (10 ～16 mg/kg)、较缺乏 (16～22 mg/kg)、中等 (22～34 mg/kg) 和丰富 (> 34 mg/kg) 五级,结合第二次土壤普查分级指标对应分析,进行省域耕地土壤有效硫丰缺现状和时空分布研究。 【结果】 1) 全省耕地土壤有效硫含量范围在0.10 ～101.90 mg/kg之间,平均值为24.99 mg/kg,中位数为21.00 mg/kg。2) 全省耕地土壤缺硫概率较大。有效硫含量处于极缺 (< 10 mg/kg)、缺乏 (10 ～16 mg/kg) 与较缺乏 (16 ～22 mg/kg) 水平的分别占总样本数的13.76%、20.91%和18.43%。3) 省域总体缺硫状况由东向西递增、南北向中间趋减。按不同农业区域比较,淮北平原的宿州、亳州和阜阳市缺硫最严重,其次是皖南山区,又以黄山市、铜陵市土壤缺硫较严重。4) 土壤类型和时空变化上,以棕壤、黄潮土、粗骨土、红壤、黄壤、紫色土和砂浆黑土等缺硫最为严重。与20年前研究分析比较,沿江平原、江淮丘陵和皖西农区缺硫趋势减弱,而皖南山区土壤缺硫状况明显加重。目前,棕壤、砂姜黑土和黄棕壤缺硫频率和风险增大,而黄潮土、黄褐土和灰潮土缺硫频率降低。 【结论】 省域耕地缺硫 (< 22 mg/kg) 面积约311.19 × 104 hm2,占全省耕地总面积的53.10%。针对棕壤、砂浆黑土、黄潮土、红壤等九类土壤缺硫比率高 (39.67% ～56.89%之间) 的现状,应推荐含硫化肥或补施硫肥,降低作物缺硫风险。      

中国南方农业中的硫

本文介绍中国南方土壤缺硫情况。根据土壤硫的收、支和硫肥对作物的效应估计,中国南方在最近的将来不会出现大面积土壤缺硫。在某些特殊情况下,冷浸田或砂土可能缺硫。预言随着化肥工业发展,将减少含硫肥料的使用。     

作物施硫生态效应研究

通过田间试验和盆栽试验研究了小白菜和油菜在不同的土壤类型、肥料品种和不同施肥量条件下的生态效应 ,结果表明施用硫肥能促进作物生长、提高其干重生物量和含硫量 ,但施用石膏效果更佳 ,并随施肥量增加 ,效果也增强。盆栽试验中 ,同一处理油菜干重生物量和含硫量都表现为黄棕壤 >红壤 >灰潮土。施用单质硫能提高土壤中的有效硫 ,有利于改变土壤缺硫状况。缺硫土壤中油菜表现出花期延迟、花粉粒发育不全等。     

江西省农田土壤有效硫现状研究

采集了江西 1 6个县市 9种主要母质的 6 0 9个农田耕层土样进行了土壤有效硫含量测定 .统计结果表明 :平均值为 2 6 7mg/kg ,缺硫和潜在缺硫样点占 39 1 % .按地区分 ,以赣南、赣东北山区缺硫最严重 ,有效硫小于 1 2mg/kg的样点占 2 6 6 %～ 4 4 7% ,其次是丘陵地区 ,有效硫小于 1 2mg/kg的样点占1 0 0 %～ 1 9 0 % .按母质分 ,以石英岩、花岗岩发育的土壤最缺 ,约占 50 %～ 6 0 % ,其次是红砂岩、泥质岩 ,缺硫为 30 %～ 4 0 % ,这些是江西省急需施用硫肥的土壤 .水稻土以黄砂泥田、麻砂泥田、红砂泥田、鳝泥田等土属有效硫缺乏面积最大 ,全省水稻土有效硫缺乏的面积约为 1 0 3 8万hm2 ,约占水稻土面积的 34 % .     

湖南省柑橘园土壤硫素及施硫效应研究

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。     

四川省土壤硫素状况的初步分析

根据全省８３４个土样有效硫分析结果，初步划出我省低硫土壤区域和土壤类型，通过讨论，旨在普及硫肥知识，提高对硫肥的认识，防患缺硫于未然。     

我国南方部分地区农业中硫的状况及硫肥的效果

我国南方热带和亚热带地区，有相当面积的作物其生态环境缺硫，缺硫受气候因素中水热条件的影响较大，年均温愈高或降雨最愈大的地区，土壤愈容易发生缺硫；缺硫还容易出现地下水位低的中低肥力田或硫肥用量不足的高产田；由花岗岩、玄武岩，砂页岩发育的土壤或质地较轻的土壤也容易发生缺硫，１９７８年以来，累计在南方几省１７８００ｈｍ＾２的耕地上试验，示范、推广磷石膏，石膏，硫磺等含硫肥料，经济，社会，生态效益均较显著     

硫对油菜产量和抗逆性的影响

通过田间小区试验 ,研究了施用硫肥对油菜的生长、产量构成因素和抗逆性的影响。结果表明 ,苏北建湖和大丰的潮土尽管土壤有效硫测定值超过临界值 ,但是 ,施用硫肥显著促进油菜的生长发育 ,提高油菜的株高、叶面积、绿叶数等生物学参数和产量。与对照相比 ,施用硫肥处理的分枝数、每株角果数、每角粒数均显著增加 ,但千粒重无显著差异。施用硫肥后植株对冻害和菌核病的抵抗力增强。本研究结果表明 ,对油菜这类需硫量大的作物 ,现有的土壤有效硫临界值不能准确反映其对硫肥的需要 ,其缺硫指标要进一步研究     

Determination of extractable sulfate and total sulfur from plant and soil material by an autoanalyzer

Abstract

The method has been modified from Sinclair^3,4 and tested for extractable sulfate and total sulfur on plant, soil, and water samples. Inorganic sulfur is extracted from plant and soil material by using dilute acidic extractants, and total sulfur is estimated from dry ashed or wet ashed material whereby various sulfur forms are oxidized to sulfate‐sulfur. The sulfate is precipitated in sample solutions as barium sulfate and determined turbidimetrically by AutoAnalyzer.

The method is rapid, precise, and sensitive enough to be used on a routine basis.     

Role of sulfur nutrition in plant and seed metabolism of Glycine max L.

The aim of present investigation has been to explore the effect of sulfur application on plant metabolism, seed yield and seed quality in soybean. The sulfur was supplied in different doses ranging as 1, 2, 4, 6 and 8 meq S L^?1. Plant supplied with 4 meq S L^?1 showed optimal growth. Plant growth and dry matter was reduced under sulfur deficiency (1 and 2 meq S L^?1) and toxicity (6 and 8 meq S L^?1). Application of sulfur increases the tissue sulfur and cysteine concentration in both leaves and seeds. The critical concentration for deficiency (CCD) and toxicity (CCT) of sulfur was observed 0.194 to 0.277% dry weight respectively. Pod yield and seed yield was also suppressed in sulfur deficiency and toxicity. In leaves sugar (reducing, non-reducing and total sugar) and starch was found to be accumulated while in seeds both were depleted under sulfur deficiency and toxicty. Seed storage proteins (albumins, globulins, glutelins and prolamins) were also reduced under sulfur stress. Thus, we conclude that sulfur deficiency and toxicity both affects the plant metabolism, yield and seed quality in terms of carbohydrates and storage proteins of soybean.     

黑龙江省主要耕地土壤硫素现状研究

本研究采集黑龙江省29个市、县,发育于5种母质的8种土壤类型143个耕层土样,分析测试其全硫、有效硫含量;结果表明黑龙江省土壤全硫含量平均值为511.90mg/kg,有效硫含量平均值为26.27mg/kg。缺硫和潜在缺硫(有效硫含量<16mg/kg)土壤以风砂土和盐碱土居多,其次是黑土、黑钙土,而草甸土硫素含量丰富。缺硫面积最大的是黑土。按母质划分,发育于砂质沉积物的土壤100%缺硫,其次是发育于河湖冲积物和沉积物土壤,缺硫达65%以上。     

Estimation of sulfur mineralization and relationships with nitrogen and carbon in soils

A 25-week laboratory study was carried out to determine sulfur, carbon, and nitrogen mineralization rates in soil samples obtained from representative soils in France. Their relationship with some of the soil properties was investigated to find a predictor of mineralized S in soils. At 20°C and 80% water-holding capacity, the S mineralization rate ranged from 0.02 to 0.16 mg kg⁻¹ day⁻¹. It was significantly positively related to soil organic C and N and to C and N mineralization rates. It was weakly related to total soil S. The results suggest that the S mineralization is predominantly driven by heterotrophic microbial activity. A predictive equation for S mineralization based on soil C content, soil pH, and clay content is proposed.     

Predicting plant sulfur deficiency in soils: results from Ohio

We developed a model for plant available sulfur (S) in Ohio soils to predict potential crop plant S deficiency. The model includes inputs of plant available S due to atmospheric deposition and mineralization of soil organic S and output due to leaching. A leaching index was computed using data on annual precipitation; soil pH and clay content that influence sulfate adsorption; and pore water velocity based upon percent sand, silt, and clay. There are five categories of S status ranging from highly deficient to highly sufficient, and the categories are defined based on whether the crop S requirement was 15 or 30kg S ha⁻¹ year⁻¹. The final database derived from the model includes 1,473 soil samples representing 443 of the 475 soil series in Ohio. For a crop requiring 15kg S ha⁻¹ year⁻¹, most soils (68.6%) were classified as variably deficient, which implies that the response to S fertilization will be variable but often positive depending on specific crop conditions. For a crop requiring 30kg S ha⁻¹ year⁻¹, 43.2% of soils were classified as variably deficient, but 49.7% were classified as moderately or highly deficient, implying that a response to S fertilization will usually or always occur. The model predicts crop S status for a single state in the USA, but with proper inputs, it should be applicable to other areas.     

Effects of previous elemental sulfur applications on oxidation of additional applied elemental sulfur in soils

Oxidation of elemental sulfur (S⁰) in 20 Chinese agricultural soils was tested and the effects of previous S⁰ applications on the oxidation of additional applied S⁰ in selected soils were investigated using laboratory, greenhouse, and field experiments. Results showed that sulfur oxidative capacities presented great variability among 20 tested soils, with a coefficient of variation of 92.4%. There were no significant relationships between S⁰ oxidation and physical and chemical properties of the selected soil. Previous S⁰ amendment significantly increased the oxidation rate of additional applied S⁰. These stimulatory effects after the first applications of S⁰ were greater than those after two applications. The percent increase in S⁰ oxidation rate due to S⁰ pretreatment was negatively correlated with the oxidation capacities of soils before S⁰ pretreatments. The significant reduction of sulfur oxidation in autoclaved soils and significant increase in S⁰ oxidation after inoculation with S⁰-treated soil suspension demonstrated that microbial oxidation was mainly responsible for the enhancement of soil oxidation ability after previous S⁰ amendments.     

福建耕地土壤硫肥效应及其临界指标研究

硫是作物生长发育所需的营养元素。根据多年多点田间试验和土壤有效硫测定,研究福建主要粮经作物的硫肥效应、土壤有效硫临界指标和耕地土壤硫肥力状况。64个田间试验表明,福建主要农作物施用硫肥平均增产10.5%,增产幅度是旱作物>水稻>香蕉;水田土壤和旱地土壤有效硫临界指标分别为23mgkg-1和25mgkg-1。根据全省372个耕层土样有效硫测定结果,土壤有效硫含量平均为27.6mgkg-1,低于土壤有效硫临界值的样品数占57.0%,其中,闽东南地区耕地土壤有效硫缺乏程度比闽西北地区高;在土地不同利用类型中,旱地土壤有效硫总体比水田匮乏,旱地土壤有效硫平均含量是茶果园>菜园>农地,其中,农地土壤有效硫低于临界指标的样品占75.3%;水田中不同土种的土壤有效硫含量以埭田最高,灰沙泥田为最低,旱地则以灰赤土最高而风沙土最低。     

河北省土壤硫含量、形态与分布

对河北省主要土壤类型耕层硫含量进行了分析测定。结果表明 ,河北省土壤全硫平均含量为 250.1mg/kg(50～940mg/kg)。土壤全硫平均含量以沼泽土最高 ,灰色森林土最低 ;土壤有效硫平均含量为 46.1mg/kg ,以沼泽土最高 ,红粘土和栗褐土最低。土壤硫主要以有机态存在 ,占全硫含量的 81.6% ;无机态硫占 18.4%。按土类划分土壤无机硫含量最高的是沼泽土 ,灰色森林土最低 ;土壤有机硫含量也以沼泽土最高 ,灰色森林土最低。土壤全硫含量主要受土壤有机质含量、阳离子代换量和土壤碳酸钙含量的影响。根据土壤硫供应水平计算 ,全省约有20.4%的土壤缺硫 ,北部缺硫面积较大 ,南部缺硫面积较小。根据土壤有效硫含量多寡 ,可把全省土壤硫含量划分为极缺乏区、缺乏区、中等区、丰富区及极丰富区 5类