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微生物肥料及其生产应用中的问题 总被引:14,自引:0,他引:14
微生物肥料和微生物制剂是新世纪实行绿色农业的重要技术保障,关键是因其中含有大量的有效微生物的生命活动产生特定的肥效或其他生理功能,导致增产,微生物肥料包括根瘤菌肥,解磷菌肥、解钾菌肥、5406菌肥,植物根际促生菌,VA菌根等等,有机肥料堆制剂中含有多种降解农业有机废料的菌种,可缩短堆肥周期,提高养份利用率,由于微生物本身的特殊性,相关市场监督机制不健全,微生物肥料的生产,应用领域存在很多问题,甚至出现明显的伪科学,科研、生产、行政各有关部门应加强基础研究,提高全民科普水平,健全市场监督机制,依靠专家设计严格试验,优选可靠技术,保证良好的经济效益和社会效益。 相似文献
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化感作用在生产中的应用 总被引:16,自引:0,他引:16
讨论了化感理论在生产实践中的应用。应用化感理论指导建立合理的栽培、耕作制度。进行田间杂草的生物控制和防治;开发新一代无公害农药;指导森林更新和建植;培育抗化感品种等。 相似文献
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心电、头皮脑电、表面肌电等传统无创生物电检测方法可为相关疾病诊断提供电学依据。由于生物电信号是机体细胞群共同放电的混叠集合结果,上述生物电检测方法空间分辨率相对有限。近些年兴起的声电成像利用无创聚焦超声空间编码生物电流,靶向获得精确聚焦位置的电信号,可实现毫米级空间分辨率、毫秒级时间分辨率的无创生物电信号检测,有望成为精准检测生命体深层电活动的新型成像技术。本文首先简述声电成像原理与声电信号特征,进而从声电耦合机理、声电成像方法、声电脑成像及声电心脏成像等方面详细介绍声电成像的典型研究,最后围绕声电成像关键技术环节所面临的挑战,对未来研究方向进行探讨,以期为建立完善的声电成像技术体系和实现其临床转化提供依据与启发。 相似文献
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随着土地资源日益短缺及人们对生态环境的关注,以天然土壤微生物为主要成分的微生物肥料应用在盐碱农业中越来越受到重视。本文综述了国内外微生物肥料的发展历史和现状,微生物肥料对盐碱土壤产生的影响,帮助植物抵抗盐胁迫的机制,以及对盐碱土壤中微生物群落产生的影响;本文也提出了两种能够有效保藏菌种的固定化方法,这两类方法能有效地解决菌种易失活问题且延长其在土壤中的作用时间;最后提出了目前微生物肥料作用于盐碱地存在的问题与展望,旨在为缓解土地资源、提高农业安全生产做出贡献。 相似文献
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组织氧合作用和光敏剂应用在疾病诊治中都有着重要的作用,因此其实时在体无损检测很有意义。光动力疗法涉及光敏剂、光和氧分子三大要素,其疗效受组织氧合作用影响。本文对光声成像(PAI)、光声寿命成像(PALI)和多光谱光声层析成像(MSOT)等光声成像技术在光动力疗法的研究和应用中的使用现状进行了综述。对相关设备系统在检测光敏剂、组织氧分压和微血管损伤等方面的应用原理和技术分别进行了介绍,并总结了这些技术的应用前景。 相似文献
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初中物理教学是自然学科中相对比较重要的学科,尤其是初中物理的知识奠定了在高中以及大学的学习基础。初中物理课程重点需要给予学生们对于物理学科的一些启蒙知识,此外还要教给学生们物理思维以及学习物理的兴趣。随着计算机技术的不断发展,信息技术在初中物理中的应用越来越深入,采用信息技术与物理教学的结合,加强了物理教学的效率,也在一定程度上提高了学生们学习的兴趣。本文重点解析,信息技术在初中物理教学中的应用。 相似文献
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Kai-Uwe Katroschan Gon?alo Teixeira Katrin Kahlen Hartmut Stützel 《Plant and Soil》2012,353(1-2):59-71
Aims
We investigated the response of the perennial grass Molinia caerulea (L.) Moench to combined effects of fertilization (N, P) and drought events. We hypothesized that N fertilization increases, and drought decreases productivity, but that N addition strengthens negative effects caused by drought.Methods
Within a full-factorial 2-year greenhouse experiment we measured biomass productivity and allocation, tissue nutrient concentrations and nitrogen allocation patterns using 15N as a tracer.Results
N fertilization caused a strong increase in productivity, but effects of drought were almost insignificant. However, we found strongly interrelated, non-additive effects of fertilization and drought, expressed by a strong increase of necrotic tissue. Dead aboveground biomass showed the highest values for N and 15N.Conclusions
Accelerated productivity of aboveground tissue under N fertilization resulted in increased evaporative demands and thus higher drought susceptibility. In addition 15N allocation patterns showed that fertilization-drought treatments disenabled plants’ control of their N allocation. Molinia was unable to withdraw leaf N during the dieback of aboveground tissue. Due to the lack of an adaptive strategy to the combined effects of fertilization and drought, increasing summer drought may weaken the competitive performance of species with traits comparable to those of Molinia in N-fertilized environments. 相似文献12.
Richard Jones 《Folia Geobotanica》1968,3(4):355-362
An experiment, in which fertilizer was used for accelerating growth for studies on production processes, is described. In this Australian heathland—a community common on soils very deficient in phosphorus and other nutrients—responses to fertilizer consisted in increases in leaf area index and standing biomass above ground. Fertilizer had no effect on growth below ground. These results were derived in the second growing season after treatment; no statistically significant effect could be shown in the non-growing periods up to two years after treatment. Discussion is centred on the limitations to be expected of such natural communities used as experimental material on which fertilizer has been imposed as a major treatment. 相似文献
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不同时期开沟施氮对水稻物质生产及产量的影响 总被引:2,自引:1,他引:2
通过田间试验 ,研究了水稻不同生育时期开沟深施氮肥对水稻叶片、叶鞘和茎秆干重以及生物产量和籽粒产量的影响 .结果表明 ,孕穗期开沟深施氮肥处理比分蘖期开沟、穗分化始期开沟和不开沟处理的水稻叶片干重保持最大值 (2 .9g/穴 )时间长 ,叶面积指数达到最大值 (LAI =8.9)后保持缓慢下降 ;叶鞘干重 (2 .7g/穴 )变化小 ;处理以后茎秆干重 (4.3g/穴 )稳步增加 .孕穗期开沟施肥处理的水稻生物产量(0 .73g·d-1/穴 )递增速度快 ,籽粒产量 (10 4 34kg·hm-2 )高 .与不开沟施肥相比 ,孕穗期开沟施氮对产量增加作用最大 ,为水稻开沟深施氮肥的最佳时期 ;其次为穗分化始期 ,分蘖期开沟施氮效果较差 ,但仍有一定的增产作用 . 相似文献
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Summary The relationships between the nutrient contents in vine leaves and grape yield on the one hand and the nutrient contents in
the soil on the other are described on the basis of results from pot and field experiments conducted over several years. The
soils were analysed by means of conventional methods as well as by electro-ultrafiltration (EUF). The following results were
obtained:
The application of high K and P fertilizer amounts in pot experiments increased the availability of Mg, Mn and Fe. A marked
rise in the Mg, Mn and Fe contents was observed in the vine leaves. The exchange processes due to fertilizer addition were
well indicated by the EUF method, whereas the results obtained by extraction with ammonium lactate (AL) and CaCl2 were unsatisfactory.
Close and highly significant correlations were found between the EUF-P, EUF-K and EUF-Mg contents on the one hand and the
P, K and Mg contents in vine leaves on the other. A close correlation also exists (r=0.91***) between grape yield and EUF-K contents.
Grape yield increases with increasing EUF-K values up to 25 mg/100 g/30 min at 20°C in pot experiments (30 cm rooting depth)
and only up to 12 mg/100 g/30 min at 20°C in field experiments. The soil in this field experiment had, however, EUF-K values
of 12 mg/100 g in the topsoil as well as in the subsoil. When assessing the limit values, it is therefore important to consider
the depth of the horizon in which the nutrients are present.
After addition of very high amounts of P fertilizer the P contents in vine leaves markedly decrease after one year, as there
is a decline in the availability of phosphates. The EUF-P values measured immediately after the application of high doses
of P fertilizer can only characterize the P supply status of a soil for a period of one or two years.
The P availability after application of different forms of phosphate fertilizers (superphosphate, hyperphosphate) is well
indicated by means of EUF, but not by means of the AL method.
When assessing the required K and Mg values in the soil (whatever the method) the vine variety has also to be taken into account,
whereas the utilization of soil phosphates depends less on the varietal differences. 相似文献
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F. W. Chichester 《Plant and Soil》1970,33(1-3):425-435
Summary Five crops of oats were grown over a 14-month period on a Chester silt loam soil fertilized with N15-labelled (NH4)2SO4. All plant material from the first four crops was returned to the soil. Following a fifth crop, oat tops and roots were harvested,
and the soil was subjected to repeated extractions by autoclaving in 0.01M CaCl2. The distribution of N15 and of indigenous soil N among chemical fractions of the extracts, and in the acid-soluble and acid-soluble and acid-insoluble
portions of the soil residues following 0.01M CaCl2 extraction, was remarkably similar. Since appreciable equilibrations between added N15 and the more resistant forms of soil organic N is unlikely, it is postulated that fertilizer N became incorporated in newly-formed
complexes, similar to those already present in the soil. This view is in harmony with the finding that percentage removals
of total and N15-labelled N remained almost the same, even with recovery of approximately 55 per cent of the amounts originally present. N
mineralization capacity of the soil was reduced appreciably as a result of extraction. 相似文献
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太湖地区黄泥土壤水稻氮素利用与经济生态适宜施氮量 总被引:22,自引:0,他引:22
通过田间试验对不同施肥水平下太湖地区黄泥土壤水稻的氮肥吸收规律和氮肥利用效率进行了研究,并应用^13N微区试验测定不同氮肥水平下氮肥损失数量。在此研究数据基础上,引入数学的微积分原理和环境经济学的Coase原理,对该地区水稻田氮肥施用的经济效益和环境效益进行评价,求得219-255kghm^-2为太湖地区黄泥土上目前生产条件下,兼顾生产、生态和经济三效益比较合理的水稻施肥量,相应的经济、生态适宜产量为8601—8662kg hm^-2。 相似文献
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Muhammad Yaseen Muhammad Zahir Aziz Abdul Aleem Jafar Muhammad Naveed 《International journal of phytoremediation》2016,18(5):502-508
A field experiment in collaboration with a private textile industry (Noor Fatima Fabrics Private (Ltd.), Faisalabad) was conducted to evaluate the effect of disposed water from bleaching unit, printing unit and end drain for improving growth and yield of wheat under saline sodic soil. Textile waste water along with canal water (control) was applied with and without liquid NPK fertilizer. The application of liquid NPK fertilizer with end drain waste water increased plant height, spike length, flag leaf length, root length, number of tillers (m?2), number of fertile tillers (m?2), 1000 grain weight, grain yield, straw yield and biological yield up to 21, 20, 20, 44, 17, 20, 14, 44, 40 and 41%, respectively compared to canal water (control). Similarly, the NPK uptake in grain was increased up to 15, 30 and 28%, respectively by liquid fertilizer treated end drain water as compare to canal water with liquid fertilizer. Moreover, concentration of different heavy metals particularly Cu, Cr, Pb and Cd was decreased in grains by application of waste water along with liquid NPK. The result may imply that waste water application along with liquid-NPK could be a novel approach for improving growth and yield of wheat in saline sodic soils. 相似文献
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Cobo F 《In vitro cellular & developmental biology. Animal》2007,43(10):371-378
Regenerative medicine therapies will allow in the future the transplant of cells of human origin in some diseases that until
now have been incurable. The assurance of the safety and quality, especially from a microbiological point of view, is very
important for these therapeutic products. Depending on the starting material, there are several sources of pathogen presence,
mainly human viruses. Also, the use of feeders of animal origin as layers in which the stem cells can grow may permit the
transmission of animal pathogens to these cells. However, cell sources are limited due to the low availability of spare in
vitro fecundation human embryos and the low rate of success in the derivation of human stem cell lines. Thus, in several cases,
it will be necessary to evaluate the possibility of removing or inactivating these microorganisms. In this paper, we summarize
the main methods of viral clearance and we have provided an overview of the main features taking into account in the viral
clearance techniques. 相似文献