共查询到20条相似文献，搜索用时 0 毫秒
1.
长期定位施肥对土壤氮素矿化与作物产量的影响 总被引：2，自引：0，他引：2
揭示长期施用有机肥及配施氮肥对非石灰性潮土氮素矿化特性的影响,探索其与作物产量间的关系。以始于_1978年的莱阳长期定位施肥试验为基础,采用田间原位-离子交换树脂法(ISC-IERB)研究了长期定位施肥对土壤氮素矿化特性的影响,并对其与产量进行了相关分析。结果表明:长期施用有机肥及其配施氮肥可显著提高非石灰性潮土全氮、矿质氮、净氮矿化量、冬小麦或夏玉米吸氮量和产量,且在同一有机肥(氮肥)水平下,均随氮肥(有机肥)投入量的增加呈增加趋势,其中高量有机肥配施高量氮肥(M_2N_2)处理的增加幅度最高,冬小麦、夏玉米产量分别为6 803,_1_1 935 kg/hm_2;长期施肥使夏玉米季土壤氮净矿化量、净氮矿化率明显大于冬小麦季,施肥处理(M_1、M_1N_1、M_1N_2、M_2、M_2N_1、M_2N_2)的增幅分别为7.1%-2.7%,16.2%-76.0%;相关分析表明,冬小麦-夏玉米产量与当季冬小麦、夏玉米播前土壤全氮、矿质氮含量、氮净矿化量均存在极显著相关性,但与氮素表观淋失量相关不显著。研究表明,施用有机肥、氮肥是提高土壤供氮潜力、作物产量的有效手段,作物与季节是影响土壤氮素矿化的重要因素。 相似文献
2.
长期施肥对不同热量带土壤供氮能力的影响 总被引：9，自引：0，他引：9
研究利用中国科学院海伦、栾城、鹰潭农业生态试验站长期定位试验,结合温室盆栽,研究了长期施肥对不同热量带土壤供氮能力的影响.为我国不同热量带下农田土壤的生产潜力,平衡施肥等提供理论依据.结果表明:长期不同施肥土壤全氮、碱解氮和矿质态氮含量的高低顺序均表现为:化肥+有机肥 > 化肥 > 无肥.长期施肥对红壤供氮能力的增加幅度最高,其次为潮褐土,最低为黑土,且长期施肥对土壤供氮能力的增加幅度与土壤所处热量带的有效积温呈显著正相关(P<0.05).在长期不同施肥的土壤上种植小麦后,施肥土壤的作物生物量显著高于不施肥土壤(P< 0.05),且作物生物量的变化规律与土壤氮素含量的变化规律大体一致,说明通过生物试验所得的生物量可作为评价土壤氮素肥力的生物学指标. 相似文献
3.
Integrated crop–livestock systems can help achieve greater environmental quality from disparate crop and livestock systems by recycling nutrients and taking advantage of synergies between systems. We investigated crop and animal production responses in integrated crop–livestock systems with two types of winter cover cropping (legume-derived N and inorganic fertilizer N), two types of tillage [conventional disk (CT) and no tillage (NT)], and whether cover crops were grazed by cow/calf pairs or not. The 13-ha field study was a modification of a previous factorial experiment with four replications on Ultisols in Georgia, USA. Recurring summer drought severely limited corn and soybean production during all three years. Type of cover crop had little influence and grazing of cover crops had minor influence on crop production characteristics. Cattle gain from grazing of winter cover crops added a stable component to production. No-tillage management had large positive effects on corn grain (95 vs. 252 g m−2 under CT and NT, respectively) and stover (305 vs. 385 g m−2) production, as well as on soybean grain (147 vs. 219 g m−2) and stover (253 vs. 375 g m−2) production, but little overall effect on winter wheat grain (292 g m−2) and stover (401 g m−2) production. Our results suggest that robust, diversified crop–livestock systems can be developed for impoverished soils of the southeastern USA, especially when managed under no tillage to control environmental quality and improve resistance of crops to drought. 相似文献
4.
比较了平作和垄作下不同保护性耕作方式对土壤水分、温度和作物生长发育和产量的影响。结果表明,几种耕作方式中平作的平均产量都要高于垄作,其增产率在11.38%￣15.20%之间。在相同的垄作或平作方式下,不同的保护性耕作方式的增产幅度不同,其中秸秆还田增产幅度最大。平作方式的出苗率、叶面积指数、根干重和干物重都高于垄作,但不同的保护性耕作方式其各项指标变化有所不同。平作下保护性耕作方式的土壤含水量高于垄作;垄作方式有一定的增温效应,尤其在苗期的土壤表层。 相似文献
5.
A study was carried out at Mushaqqar Agricultural Experiment Station located in the Central Highlands of East Jordan. The objectives were to study and compare three crop rotations: Duck foot fallow–wheat; chemical fallow–wheat; and wheat–wheat, on soil moisture conservation and storage and on wheat yield.
Results indicated that, the storage efficiency for the duck foot fallow treatment was higher than that of chemical fallow (13.4 and 8.7% respectively). Also it was found that two duck foot or chemical fallow applications, for weed control, were needed before June.
Wheat yield was the highest after the duck foot fallow, followed by chemical fallow. Wheat yield had decreased from 3.34 Mg/ha to 1.08 Mg/ha, for continuous wheat. 相似文献
Results indicated that, the storage efficiency for the duck foot fallow treatment was higher than that of chemical fallow (13.4 and 8.7% respectively). Also it was found that two duck foot or chemical fallow applications, for weed control, were needed before June.
Wheat yield was the highest after the duck foot fallow, followed by chemical fallow. Wheat yield had decreased from 3.34 Mg/ha to 1.08 Mg/ha, for continuous wheat. 相似文献
6.
7.
8.
High rates of nitrogen (N) fertilizer may increase N leaching with drainage, especially when there is no further crop response. It is often discussed whether leaching is affected only at levels that no longer give an economic return, or whether reducing fertilization below the economic optimum could reduce leaching further. To study nitrate leaching with different fertilizer N rates (0–135 kg N ha−1) and grain yield responses, field experiments in spring oats were conducted in 2007, 2008 and 2009 on loamy sand in south-west Sweden. Nitrate leaching was determined from nitrate concentrations in soil water sampled with ceramic suction cups and measured discharge at a nearby measuring station. The results showed that nitrate leaching per kg grain produced had its minimum around the economic optimum, here defined as the fertilization level where each extra kg of fertilizer N resulted in a 10 kg increase in grain yield (85% DM). There were no statistically significant differences in leaching between treatments fertilized below this level. However, N leaching was significantly elevated in some of the treatments with higher fertilization rates and the increase in nitrate leaching from increased N fertilization could be described with an exponential function. According to this function, the increase was <0.04 kg kg−1 fertilizer N at and below the economic optimum. Above this fertilization level, the nitrate leaching response gradually increased as the yield response ceased and the increase amounted to 0.1 and 0.5 kg kg−1 when the economic optimum was exceeded by 35 and 100 kg N ha−1, respectively. The economic optimum fertilization level depends on the price relationship between grain and fertilizer, which in Sweden can vary between 5:1 and 15:1. In other words, precision fertilization that provides no more or no less than a 10 kg increase in grain yield per kg extra N fertilizer can be optimal for both crop profitability and the environment. To predict this level already at fertilization is a great challenge, and it could be argued that rates should be kept down further to ensure that they are not exceeded due to overestimation of the optimum rate. However, the development of precision agriculture with new tools for prediction may reduce this risk. 相似文献
9.
This work was aimed at providing a sustainable approach in the use of manure in irrigated maize crop under Mediterranean climatic conditions. To this end, the effect of continuous annual applications of dairy cattle manure, combined or not with mineral N fertilizer, on the following parameters was studied: grain yield, grain and plant N concentration, N uptake by plant, N use efficiency, and soil N and organic carbon. The experiment was conducted in a furrow-irrigated sandy soil under dry Mediterranean conditions during seven years. Three different rates of cattle manure (CM): 0, 30 and 60 Mg ha−1, were applied each year before sowing. These CM rates were combined with four mineral N rates (0, 100, 200 and 300 kg N ha−1) applied at sidedress.On average, the highest grain yields during the 7 years were obtained with the combination of CM at 30 Mg ha−1 and mineral fertilizer and with CM at 60 Mg ha−1 without mineral fertilizer. With CM at 30 Mg ha−1, mineral fertilizer increased yields during most of the growing seasons, meanwhile with CM at 60 Mg ha−1, there was not any significant effect of the joint application of mineral fertilizer on yields. Overall, best results were obtained exceeding maximum rates according to present legislation. The mean apparent nitrogen recovery (ANR) fraction during the 7 seasons was 29% for N exclusively applied as CM. Overall, increased N rates applied as CM resulted in decreased ANRs. However, ANR with CM at 30 and 60 Mg ha−1 increased during the first two seasons. This increased ANR ascribed to mineralization of residual organic N applied in previous seasons explained the increasing yields observed in the treatments along the study.The application of CM during 7 years increased the soil organic carbon in the first 30 cm by 5.7 and 9.9 Mg ha−1 with CM at 30 and 60 Mg ha−1, respectively, when compared to the initial stock. Thus, manure-based fertilization could be an alternative to mineral fertilizer in order to achieve high maize yields while improving soil quality under dry Mediterranean conditions. 相似文献
10.
11.
With the practice of conservation agriculture (CA) soil water and nutrient dynamics are modified by the presence of a mulch of crop residues and by reduced or no-tillage. These alterations may have impacts on crop yields. The crop growth model DSSAT (Decision Support Systems for Agrotechnology Transfer) has recently been modified and used to simulate these impacts on crop growth and yield. In this study, we applied DSSAT to a long-term experiment with maize (Zea mays L.) grown under contrasting tillage and residue management practices in Monze, Southern Province of Zambia. The aim was (1) to assess the capability of DSSAT in simulating crop responses to mulching and no-tillage, and (2) to understand the sensitivity of DSSAT model output to input parameters, with special attention to the determinants of the model response to the practice of CA. The model was first parameterized and calibrated for the tillage treatment (CP) of the experiment, and then run for the CA treatment by removing tillage and applying a mulch of crop residues in the model. In order to reproduce observed maize yields under the CP versus CA treatment, optimal root development in the model was restricted to the upper 22 cm soil layer in the CP treatment, while roots could optimally develop to 100 cm depth under CA. The normalized RMSE values between observed and simulated maize phenology and total above ground biomass and grain yield indicated that the CA treatment was equally well simulated as the CP treatment, for which the model was calibrated. A global sensitivity analysis using co-inertia analysis was performed to describe the DSSAT model response to 32 model input parameters and crop management factors. Phenological cultivar parameters were the most influential model parameters. This analysis also demonstrated that in DSSAT mulching primarily affects the surface soil organic carbon content and secondly the total soil moisture content, since it is negatively correlated with simulated soil water evaporation and run-off. The correlations between the input parameters or crop management factors and the output variables were stable over a wide range of seasonal rainfall conditions. A local sensitivity analysis of simulated maize yield to three key parameters for the simulation of the CA practice revealed that DSSAT responds to mulching particularly when rooting depth is restricted, i.e., when water is a critical limiting crop growth factor. The results of this study demonstrate that DSSAT can be used to simulate crop responses to CA, in particular through simulated mulching effects on the soil water balance, but other, often site-specific, factors that are not modeled by DSSAT, such as plough pan formation under CP or improved soil structure under CA, may need to be considered in the model parameterization to reproduce the observed crop yield effects of CA versus CP. 相似文献
12.
Under irrigated Mediterranean conditions, no-tillage permanent bed planting (PB) is a promising agriculture system for improving soil protection and for soil carbon sequestration. However, soil compaction may increase with time up to levels that reduce crop yield. The aim of this study was to evaluate the mid-term effects of PB on soil compaction, root growth, crop yield and carbon sequestration compared with conventionally tilled bed planting (CB) and with a variant of PB that had partial subsoiling (DPB) in a Typic Xerofluvents soil (Soil Survey Staff, 2010) in southern Spain. Traffic was controlled during the whole study and beds, and furrows with (F + T) and without traffic (F − T), were spatially distinguished during measurements. Comparisons were made during a crop sequence of maize (Zea mays L.)—cotton (Gossypium hirsutum L.)—maize, corresponding to years 4–6 since trial establishment. After six years, soil compaction was higher in PB than in CB, particularly under the bed (44 and 27% higher in top 0.3- and 0.6-m soil layers, respectively). Around this time, maize root density at early grain filling was 17% lower in PB than in CB in the top 0.6-m layer. In DPB, the subsoiling operation was not effective in increasing root density. Nevertheless, root density appeared to maintain above-ground growth and yield in both PB and DPB compared to CB. Furthermore, at the end of the study, more soil organic carbon was stocked in PB than in CB and the difference increased significantly with a depth down to 0.5 m (5.7 Mg ha−1 increment for the top 0.5-m soil layer). Residues tended to accumulate on furrows, and this resulted in spatial and temporal differences in superficial soil organic carbon concentration (SOC) in the permanent planting systems. In PB, SOC in the top 0.05-m layer increased with time faster in furrows than on beds, and reached higher stable values (1.67 vs. 1.09% values, respectively). In CB, tillage homogenized the soil and reduced SOC in the top 0.05-m layer (average stable value of 0.96% on average for beds and furrows). 相似文献
13.
以保护性耕作长期定位试验为研究对象,比较分析了华北平原保护性耕作与传统耕作冬小麦田土壤水分的动态变化、作物耗水量、水分利用效率及作物产量。结果表明：免耕冬小麦田0-180 cm土壤含水量高于翻耕,随土层深度的加深含水量之间差异减少。土体0-30 cm贮水量呈波浪状变化,其中免耕具有很好的蓄水保墒作用;耕作处理之间0-180 cm的土体贮水量虽无显著差异,但免耕处理土体贮水量高于翻耕,秸秆还田高于无秸秆处理。秸秆直立免耕（ZT1）处理作物耗水量最少,分别比翻耕（CT）,翻耕＋秸秆还田（CTR）,旋耕＋秸秆还田（RTR）,秸秆粉碎免耕（ZT2）少消耗3.8,39.6,55.8,61.8 mm的水分;ZT1处理的产量为5 139.7 kg/hm^2,比CT（7 314.8 kg/hm^2）减产29.7%;ZT1处理水分利用效率为13.9 kg/（mm.hm^2）比CT减少32.4%。 相似文献
14.
渭北旱塬免耕/深松轮耕麦田产量和土壤水分对施肥的响应模拟 总被引：1，自引：0，他引：1
为探索不同肥力水平对渭北旱塬连作冬小麦田在长周期免耕/深松轮耕措施下土壤蓄水保墒和作物增产效应的影响,在模拟精度验证基础上,应用Win EPIC模型长周期定量模拟研究了1980–2009年渭北旱塬免耕/深松轮耕连作麦田5个不同施肥水平下(T1,N 75 kg hm–2+P2O5 60 kg hm–2;T2,N 120 kg hm–2+P2O5 90 kg hm–2;T3,N 150 kg hm–2+P2O5 120 kg hm–2;T4,N 180 kg hm–2+P2O5 150 kg hm–2;T5,N 255 kg hm–2+P2O5 90 kg hm–2)冬小麦产量和土壤水分效应。在30年模拟期间,各处理的冬小麦产量、年度耗水量和水分利用效率均呈波动下降趋势,下降幅度表现为T5T4T3T2T1。0~5 m土层土壤有效含水量呈季节性波动降低趋势,且随施肥水平的升高而降低,5个处理的麦田平均干燥化速率依次为每年13.5、17.1、17.4、20.1和23.9 mm。0~1.5 m土层土壤湿度随季节降水波动;各处理在不同深度形成稳定的土壤干层,其中T1在1.5~2.0 m,T2和T3在1.5~3.0 m,T4和T5在1.5~4.0 m。上述结果表明,随着肥力水平的增加,旱作冬小麦产量和耗水量也增加,土壤干层加厚。综合考虑认为,在渭北旱塬免耕/深松轮耕长期连作小麦田适宜的施肥量为纯氮150 kg hm–2+P2O5 120 kg hm–2。 相似文献
15.
保护性耕作采用少、免耕技术,地表有覆盖物,肥料一般不能通过翻耕、旋耕等方式与土壤混合,传统施肥模式不适用于保护性耕作。为解决保护性耕作推广过程中存在的施肥量不足、施肥模式单一、秸秆覆盖量少等问题,利用平衡施肥技术确定施肥量,采用裂区试验设计,主处理为耕作方式,包括翻耕、留茬免耕、整秆覆盖免耕,副处理为施肥模式,P、K肥随播种一次完成,尿素追施,一次追施、二次追施为副处理,进行保护性耕作不同施肥模式下春玉米产量与经济效益分析。结果表明,在施肥量一定的情况下,目标产量实现与耕作覆盖方式、施肥模式有密切关系。耕作方式与施肥方法最优组合为—A3B2(整秆覆盖免耕2次追肥),经济效益最高,对春玉米保护性耕作施肥管理要点进行了总结 相似文献
16.
为探讨在冀中南山前平原小麦-玉米两熟区发展保护性耕作技术的可行性,于2003—2004年度,在藁城廉州镇,就免耕、深松耕、旋耕3种不同的耕作方式对冬小麦作物产量和田间土壤水分变化状况的关系进行了试验研究。通过对不同耕作方式下,小麦生育期田间苗情和成熟期产量性状调查结合定期的土壤水分测定分析,探明了不同耕作方式对小麦产量和水分利用状况的影响。结果表明,免耕和深松耕的耕作方式,有利于改善土体结构,增加土壤蓄水保墒性能,提高水分利用效率,节水、节本、增产增效明显,发展前景广阔。 相似文献
17.
B. Basso D. Cammarano D. Chen G. Cafiero M. Amato G. Bitella R. Rossi & F. Basso 《Journal of Agronomy and Crop Science》2009,195(4):301-312
Wheat yield and protein content are spatially variable because of inherent spatial variability of factors affecting the yield at field scale. In Mediterranean environments, yield variability is often caused by the irregular weather pattern, particularly rainfall and by position on the landscape. The objective of this study was to determine the effects of landscape position and rainfall on spatial variability of wheat yield and protein in a rolling terrain field of Southern Italy, and to propose stable management areas through simulation modelling and georesistivity imaging in rolling landscape. The study was carried out in Southern Italy, during 2 years of wheat monoculture; extensive soil properties and in-season plant measurements were measured. This study showed that soil water content was the main factor affecting spatial variation of yield for both years. The interactions between rainfall, topography and soil attributes increase the chances to observe yield variability among years. The principal component analysis demonstrated that for both years, soil water content explained most of the variability. The crop simulation model provided excellent results when compared with measured data with root mean square error of 0.2 t ha−1 . The simulated cumulative probability function showed that the model was able to confirm the yield temporal stability of three different zones. 相似文献
18.
N. Brisson C. Gary E. Justes R. Roche B. Mary D. Ripoche D. Zimmer J. Sierra P. Bertuzzi P. Burger F. Bussire Y. M. Cabidoche P. Cellier P. Debaeke J. P. Gaudillre C. Hnault F. Maraux B. Seguin H. Sinoquet 《European Journal of Agronomy》2003,18(3-4):309
is a model that has been developed at INRA (France) since 1996. It simulates crop growth as well as soil water and nitrogen balances driven by daily climatic data. It calculates both agricultural variables (yield, input consumption) and environmental variables (water and nitrogen losses). From a conceptual point of view,
relies essentially on well-known relationships or on simplifications of existing models. One of the key elements of
is its adaptability to various crops. This is achieved by the use of generic parameters relevant for most crops and on options in the model formalisations concerning both physiology and management, that have to be chosen for each crop. All the users of the model form a group that participates in making the model and the software evolve, because
is not a fixed model but rather an interactive modelling platform. This article presents version 5.0 by giving details on the model formalisations concerning shoot ecophysiology, soil functioning in interaction with roots, and relationships between crop management and the soil–crop system. The data required to run the model relate to climate, soil (water and nitrogen initial profiles and permanent soil features) and crop management. The species and varietal parameters are provided by the specialists of each species. The data required to validate the model relate to the agronomic or environmental outputs at the end of the cropping season. Some examples of validation and application are given, demonstrating the generality of the
model and its ability to adapt to a wide range of agro-environmental issues. Finally, the conceptual limits of the model are discussed. 相似文献
19.
20.
摘要：将福建省划分为三个水稻种植区,选取19个样点,采用近5年（2000-2004年）中逢单年份的产量进行CERES-Rice模型参数的调试,逢双年份的产量用于检验模型在研究区域的适用性;利用GISS GCM Transient Run 的输出值生成了每个样点2030及2050年的气候变化情景;在各情景文件下运行CERES-Rice模型,并将模拟结果与当前气候情景(BASE情景)下的模拟值进行比较,再结合蒸散比（β）、产量波动系数(F)等指标,定量评价了未来气候渐变过程对福建省水稻生产的影响;在此基础上提出了适应气候渐变的若干可能对策。研究结果表明：在未来气候变化过程中,（1）研究区域水稻生长季的土壤水分条件将变得不如目前湿润;（2）研究区域早稻及单季稻生育期都将不同程度的缩短,后季稻2050情景下有所延长;（3）闽东南及闽西北双季稻区产量在未来两种气候情景下均表现为减产,且减产幅度随温度升高而加大。闽西北山地气候的单季稻区表现为增产;（4）当前闽东南水稻的稳产性最差,闽西北双季稻区的稳产性较好。未来气候变化中水稻稳产性将变差;（5）未来两种气候情景下福建省水稻总产将随着温度的升高而减少。 相似文献