黄土母质生土当年施肥对谷类作物生产力与根际土壤营养及生物活性的影响

连续3年试验研究了黄土母质生土当年施肥对谷类作物生产力与根际土壤营养及生物活性的影响。结果表明:黄土母质生土当年施肥促进了作物根系生长、生产力增加,强大的根土系统又促进了微生物的繁衍、酶活性及土壤营养的提高。黄土母质生土的熟化利用过程需用地养地相结合,重视生物改土。本研究表明,高粱、玉米均可作为生土改良沃化的先锋作物,高粱根系强壮,入土深,生物量大;而玉米虽根重、最大根长、一级节根数低于高粱,但根际土壤微生物数量多,酶活性高。而黍子根系柔弱,根际土壤生物活性较低,与高粱、玉米相比,不宜作为生土改良的先锋谷类作物。黄土母质生土对外源的辅助能(当年施肥)反应十分敏感,施肥的增产效应与土壤培肥都十分显著。黄土母质生土熟化沃化过程既是一个生土培肥改良过程,也是一个物质能量(营养)投入转化过程,并经植物物质生产过程、土壤微生物分解矿化过程及土壤生物化学酶系统促进过程三者互动,共同构成根土苗微生物物质能量转化的生态系统。     

新修梯田改良土壤物理性状对培肥地力建立高产稳产田的作用——旱地梯田“丰产沟”耕作法研究

在丘陵沟垥区,红土新修梯田上采用"丰产沟"耕作法,既改良了土壤物理性状,加速土壤熟化,培肥土壤,又夺得当年粮食高产。     

黄土母质生土当年施肥对混作根际土壤生物活性及土壤营养的影响

以黄土母质生土为供试土壤,采用盆栽试验,探讨了黄土母质生土当年施肥对小麦与豆科牧草、十字花科油菜混作根际土壤生物活性、土壤营养以及小麦根苗生长的影响。结果表明:黄土母质生土当年施肥促进了混作根际土壤微生物的繁衍、酶活性及土壤营养的提高。4种混作处理研究还表明,豌/麦、苜/麦根际土壤综合效应最好,可作为生土改良沃化的先锋混播作物。黄土母质生土对外源的辅助能(当年施肥)反应十分敏感,施肥促进小麦根苗生长效应与土壤培肥效应十分显著。黄土母质生土熟化过程既是一个生土培肥改良过程,也是一个物质能量(营养)投入转化过程,并经作物的光合生产过程、土壤微生物分解矿化过程及土壤酶系统活化过程,共同构成根土苗微生物互动的生态系统。该研究为混作复合群体应用于黄土母质生土地的改良提供了理论参考。     

有机生物活性肥料对冬小麦生长及土壤活性质量影响的试验研究

试验结果表明,在无机营养水平相当条件下,冬小麦应用腐殖酸生物活性肥料表现群体发育动态平稳,明显改善植株性状及产量构成因素,增强抗逆性能,增产6.6%～15.2%,产量差异达到0.01显著水平;同时能够促进土壤有益微生物繁衍并延缓衰减速率,提高土壤酶活性,从而可以培肥土壤,提高土壤肥力,达到增产增收的目的。     

不同施肥措施对棉田土壤微生物量及其活性的影响

通过测定不同施肥措施下棉田土壤微生物量及微生物活性的动态变化,探讨了不同施肥措施对棉田土壤的培肥效应,结果表明,有机肥合理配施N、P、K化肥,可以促进土壤微生物量显著增长,土壤呼吸强度、纤维素分解强度等微生物活性指标明显提高,增强了土壤养分容量及供应强度,有利于培肥土壤。     

不同培肥处理对采煤塌陷地复垦不同年限土壤熟化的影响

利用不同培肥处理对晋城煤矿采煤塌陷区复垦土壤熟化效果进行研究,结果表明:每个培肥处理施入土壤中氮(N)、磷(P2O5)养分相同时,经过玉米、小麦的轮作后,各培肥处理对复垦土壤(不同年限)熟化有不同的效果。其中,各处理的土壤全氮、全磷、过氧化氢酶、磷酸酶变化差异不显著;土壤速效N、P、有机质、微生物量碳、氮以及转化酶、脲酶增加较为明显。与对照相比,化肥+有机肥+菌肥处理的培肥效果最为显著,速效氮、磷增加了21.8%,25.5%,有机质增加了14.2%,微生物量碳、氮增加了17.2%,14.8%,转化酶、磷酸酶和脲酶的增量分别达到了10.2%,16.0%,25.0%,其余培肥处理的效果为:化肥+有机肥有机肥化肥对照。     

新修梯田覆膜种玉米培肥试验

<正> 针对新修梯田土壤结构不良,土性阴冷,土壤肥力低,微生物活性差等特点,我们于1988～1990年开展了新修水平梯田覆盖地膜种玉米培肥试验,试图通过高投入(增施有机肥、化肥)和保墒增温措施,加速培肥土壤,实现新修水平梯田早期丰产,取得较好的增产效果。     

风化煤玉米秸配施熟化土壤的生物学效应研究

以黄土母质生土为材料,通过盆钵试验,研究了腐殖酸类物质风化煤与玉米秸配施在土壤熟化培肥过程中对土壤微生物量及生物活性的综合影响。结果表明,施用风化煤,特别是与玉米秸配施,对土壤生物量C和土壤呼吸强度、纤维分解强度等表征土壤生物学性状的指标均有不同程度的促进作用,互作激发效应较明显,有较好的实际应用价值。经统计优选,在本试验条件下,对土壤微生物及其活性具有较佳效应的方案为风化煤施用量24150～32400kg/hm2,同时配施玉米秸35550～41550kg/hm2,尿素1080～1290kg/hm2。     

不同培肥管理措施对土壤微生物生态特征的影响

本文研究了厩肥区、秸杆区、化肥区和无肥对照区四种不同培肥管理措施对土壤微生物生态特征的影响,结果表明,施入厩肥、化肥或秸杆还田均能明显增加土壤微生物生物量及呼吸量;土壤微生物生物质量、土壤呼吸及代谢商等微生物指标均与土壤有机质的变化呈相同的变化趋势;BIOLOG生态盘测试亦揭示了培肥管理措施能明显影响土壤微生物的群落结构。     

攀西地区新垦地土壤沙化特征与防治措施的研究

对比分析攀地区第三系昔格达组质发育的土壤在不同土地利用条件下颗粒组成,团聚状况,有机质含量及其它营养特性,并采用4种处理措施对同一母质新垦地土壤进行了3年培肥,结果表明,该母质在当地气候条件下的土壤沙粒含量偏高,粘粒易流失,热熟化度情况下存在明显沙化倾向,＜0.01mm物理粘粒的团聚度与有机质呈极显著正相关,因此,防止占攀西地区60％以上新垦地的昔格达终发育的土壤冲刷和沙化的关键是尽快熟化土壤,提高有机质含量,4个处理中,以“聚土成畦（垄）,稿秆深埋还田,带状培肥“效果最好,经3年培肥后土壤冲刷和沙化的关键是心快熟化土壤,提高有机质含量,4个处理中,以“聚土成硅（垄）,稿秆深埋还用,带状培肥“效果最好,经3年培肥后土壤有机质可达11．7g/kg,增长率达166％,其次是水旱轮作和平作＋有机肥。     

Microbial diversity and multidimensional interactions in the rice ecosystem

The sustainability of rice production systems globally is intricately related to the chemistry, physics and biology of rice soils – with basic properties differing considerably in wet/dry land soils, tropical/temperate areas or even with the soil surface or rhizosphere niche of the field. Rice fields represent unique aqua-terrestrial ecosystems in which the tremendous diversity of soil microbes, soil fauna and plants – ranging in function from nitrogen fixers, nitrifiers, methanogens, methane oxidizers, phosphate-dissolving microbes, sulfur oxidizers to catabolizers of pesticides is observed. This diversity is inclusive of bacteria, cyanobacteria, archaea, planctomycetes and β-proteobacteria, besides the increasing members of endophytes associated. The complexity and dynamic nature of this ecosystem requires in-depth investigations of the tripartite interactions among plants, microbes and the soil–water environment. This needs to be complemented with studies on the ecological compartmentalization due to diffusion gradients of nutrients and gases, which is of extreme significance in the current scenario of problems associated with greenhouse gas emissions from agricultural areas, especially rice paddies. This article provides an overview of the interactions between the microflora and crop, with emphasis on nutrient transformations in the rhizosphere, so as to develop effective and efficient environmentally sustainable strategies for this crop.     

Identifying management zones in agricultural fields using spatially constrained classification of soil and ancillary data

Site‐specific management requires accurate knowledge of the spatial variation in a range of soil properties within fields. This involves considerable sampling effort, which is costly. Ancillary data, such as crop yield, elevation and apparent electrical conductivity (EC_a) of the soil, can provide insight into the spatial variation of some soil properties. A multivariate classification with spatial constraint imposed by the variogram was used to classify data from two arable crop fields. The yield data comprised 5 years of crop yield, and the ancillary data 3 years of yield data, elevation and EC_a. Information on soil chemical and physical properties was provided by intensive surveys of the soil. Multivariate variograms computed from these data were used to constrain sites spatially within classes to increase their contiguity. The constrained classifications resulted in coherent classes, and those based on the ancillary data were similar to those from the soil properties. The ancillary data seemed to identify areas in the field where the soil is reasonably homogeneous. The results of targeted sampling showed that these classes could be used as a basis for management and to guide future sampling of the soil.     

聚合物包膜控释肥料膜壳累积、降解及对土壤质量影响的研究进展

聚合物包膜控释肥料是实现化肥提质增效的新型肥料之一,其控释效果依赖于包膜材料。控释肥料养分释放后的残留膜壳是农业土地上微塑料的重要来源,膜壳及其降解产物是否对土壤质量安全造成影响尚不清楚。本文综合了国内外膜壳残留及其降解的研究进展,从聚合物包膜控释肥料残留膜壳在农田中的累积现状、降解性能研究及其对土壤物理–化学–生物学效应等土壤质量参数的影响进行了阐述,包括:1)现有文献指出,控释肥料膜壳在农田中的累积量与施用量基本相同,其在不同类型农田土壤及不同土层中的赋存、分布和累积现状不同;2)不同类型控释肥料膜壳在土壤中的降解过程主要与聚合物材质相关,降解率可通过聚合物材料改性来提高,其降解过程、产物及机制值得探索;3)控释肥料膜壳降解产物对土壤物理、化学、生物学性状及作物生长的影响程度取决于聚合物材料类型、累积量及土壤类型。短期内低浓度的膜壳累积对土壤理化性质、土壤生物及作物生长无不良影响,长期累积或高浓度下膜壳影响土壤质量变化的阈值亟需明确。据此,进一步提出,1)应广泛开展不同种类控释肥料膜壳在农田中的赋存、分布和累积的现场监测评估工作;2)开发控释肥料膜壳及其次级降解物分离提取、鉴定和定量表征的分析技术和方法,建立健全标准化方法;3)了解控释肥料膜壳及其降解产物在土壤中的去向和迁移过程及其对不同类型土壤及不同作物品种的影响,探寻膜壳残留量与效应之间的关系及其影响机制;4)研制开发天然、生物及可降解控释肥料膜材,研究膜壳降解与养分释放之间的相互关系,构建新型可生物降解控释肥料膜壳降解与养分释放关系数据模型,以期为聚合物包膜控释肥料的应用、开发及标准的制定提供科学依据。     

水稻连续免耕抛栽对土壤理化和生物学性状的影响

于2005~2007年在双季稻田以翻耕处理为对照,研究了水稻连续免耕抛栽对土壤理化和生物学性质的影响。结果表明,稻田免耕1年(2季),有利于土壤物理性状的改善,随着免耕时间(3年6季)的延长,土壤物理性质变差。但免耕2年后,采用紫云英和稻草还田能降低免耕稻田的土壤容重,提高总孔隙度和非毛管孔隙度。免耕有利于土壤养分在表层土壤富集。土壤中三大类微生物总量免耕处理小于翻耕处理,免耕土壤细菌的数量增加,而放线菌和真菌的数量减少。土壤中脲酶活性增加,而过氧化氢酶和过氧化物酶的活性均降低。脲酶、过氧化氢酶和多酚氧化酶的活性均与土壤有机质、全氮含量呈极显著相关,而过氧化物酶活性则与土壤全氮和速效钾含量呈极显著相关。该结果有水稻免耕抛秧栽培技术的推广应用的参考意义。     

Changes in the physical status of the typical and leached chernozems of Kursk oblast within 40 years

The changes in the physical properties of the chernozems in the Central Russian province of the forest-steppe zone (Kursk oblast) that took place from 1964 to 2002 are analyzed in relation to the corresponding changes in the agrotechnology, agroeconomy, and agroecology. Three periods of the soil transformation are distinguished. The first period was characterized by the use of machines with relatively small pressure on the soil and by the dynamic equilibrium between the physical state of the soils and the processes of the humification-mineralization of the soil organic matter. The use of power-intensive machines in the next period resulted in greater soil compaction with negative changes in the soil physical properties. At the same time, the physical properties of the chernozems remained close to optimum on the fields where heavy machines were not used. The third period was characterized by the use of heavy machines and by the decrease in the rates of the organic and mineral fertilizers and certain disturbances in the crop rotation systems because of the economic difficulties. The negative tendencies of the changes in the soil physical properties observed during the preceding period continued.     

Exploring the spatial relations between cereal yield and soil chemical properties and the implications for sampling

Abstract. In general, agricultural management has focused on differences between fields or on the gross differences within them. Recent developments in agricultural technology, yield mapping, Global Positioning Systems and variable rate applications, have made it possible to consider managing the considerable variation in soil and other properties within fields. This system is known as precision agriculture. More precise management of fields depends on a better understanding of the factors that affect crop input decisions. This paper examines the spatial variation in crop yield, soil nutrient status and soil pH within two agricultural fields using geostatistics. The observed properties vary considerably within each field. The relation between yield and the measured soil properties appears to be weak in general. However, the range of spatial correlation for yield, shown by the variogram, is similar to that of the soil chemical properties. In addition the latter changed little over two years. This suggests that information on the scale of variation of soil chemical properties can be derived from yield maps, which can also be used as a guide to a suitable sampling interval for soil properties.     

Using selected soil physical properties of seedbeds to predict crop establishment

Seedbed preparation can involve a wide range of tillage methods from intensive to reduced cultivation systems. The state or quality of the soil to which these tillage methods are applied for cereal crop management is not easily determined and excessive cultivations are often used. Seedbed preparation is crucial for crop establishment, growth and ultimately yield. A key aspect of the soil condition is the soil physical environment under which germination, growth and establishment occur. Crucially this affects factors such as temperature, water content, oxygen availability, soil strength and ultimately the performance of a seedbed. The dynamics of soil physical properties of a range of seedbeds and how they relate to crop establishment are considered in this paper. Significant interactions between cultivation techniques, physical properties of the seedbed in terms of penetration resistance, shear strength, volumetric water content and bulk density and the interaction with crop establishment were identified. A soil quality of establishment (SQE) model was developed for the prediction of crop establishment based upon soil bulk density and cultivation practices. The SQE significantly accounted for ca. 50% of the variation occurring and successfully predicted crop establishment to a standard error of around 20 plants per m⁻² across contrasting soil types and environmental conditions.     

作物土传病害防控的健康微生物群落构建原理与实践

植物-土壤反馈效应及农田生产特点决定了农田土壤生产力的不可持续性,因而必须采用适当的措施方可保持地力常新。施用化肥解决了农田土壤的养分贫化问题,极大地提高了作物产量,但激发了土传病原生物的活性,作物土传病频发成为制约集约化农业可持续发展的瓶颈问题。现有的研究成果表明,地上生物多样性与土壤微生物多样性紧密联系,植物提供的有机物质是连接二者的物质基础。单一作物种植的集约化农业提供给土壤微生物可利用的有机物质来源单一,导致土壤微生物多样性下降,削弱对土传病原生物致病性的抑制作用。本文提出,在作物生长过程中添加土壤有益微生物偏好利用的有机物质,激活土壤有益微生物,可能是维持集约化农业土壤生物健康,抑制作物土传病的有效途径。为此,有必要开展各种土壤微生物偏好利用的有机物质以及作物生长过程中如何施用有机物质的方法。     

Tillage and soil physical properties in semi-arid West Africa

In the semi-arid zone of West Africa, the growth of annual crops is severely constrained by soil and climatic conditions. Soil physical properties, specifically low porosity resulting from the particle-size distribution and predominantly low-activity clay, restricts root system development and crop growth. Using intensive mechanical tillage is an effective method in enhancing soil porosity and physical properties.

This paper summarizes the results of tillage experiments conducted for about 30 years in West Africa. Tillage methods evaluated involved deep plowing with motorized equipment or animal powered tools using tined equipment and ridgers for earthing up. Soil properties and plant characteristics evaluated were porosity, root development, microbial life, soil-water reserves, and crop yields. Results of no-tillage and minimum-tillage studies are also discussed. Application of reduced tillage techniques did not produce satisfactory results. Several mulch farming systems, using dead or living vegetative covers, were also tested in regions where annual rainfall exceeds 1000 mm.

The results obtained support the conclusion that soil tillage is an excellent means of improving soil physical properties and crop yields in the semi-arid regions of West Africa. However, adaptation of this technique by resource-poor small farmers poses several technical and logistical problems.     

漳河灌区农田地表排水中磷素流失特征分析

:为了揭示农田面源污染的机理及其成因,该文选取湖北省漳河灌区的典型试验田作为试验对象,在田间试验结果进行分析的基础上,研究了水稻和玉米2种作物在不同处理方式下农田排水磷素流失的影响因子及其规律。试验结果表明,降雨强度、作物类型、农业耕作管理方式（包括灌溉施肥方式等）是农田磷素流失的主要影响因素;另外,土壤物理化学特性和地形地势等也在一定程度上影响农田磷素的流失。