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微生物资源的开发利用与农业可持续发展 总被引：23，自引：1，他引：23
对微生物资源在农业可持续发展中的作用及其合理开发利用进行了阐述和总结。认为微生物作为一种宝贵的资源，它与农业可持续发展的关系十分密切，它在土壤肥力的提高与保持、营养元素的转化、环境净化与生态系统的平衡等方面起着极其重要的作用。因此，加强以微生物肥料、微生物农药、微生物食品、微生物饲料、环境激素和环境工程微生物等为核心的农业清洁生产技术的研究与开发利用将具有广阔的应用前景。微生物农业即所谓的“白色农业”将成为未来农业可持续发展的重要方向之一。 相似文献
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随着农药在农业中的广泛应用,显著地增加了兽医工作在预防动物中毒,以及在饲料中和畜产品中检测农药残留的重要性。用农药直接处理或者植物从土壤中吸收农药,都会使饲料植物受到污染。因此,在利用含有残留农药的饲料时,在各种情况下都必须考虑农药允许的残留量。作者用倍硫磷,二嗪农和伏杀磷作了长 相似文献
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土壤学不应忽视对作物土传病原微生物的研究 总被引：14，自引：1，他引：13
随着集约化种植程度的提高,管理不善、单一作物连续种植、秸秆还田等因素导致的土传病害日益严重,使作物高产对农药的依赖程度不断提高,对我国农业可持续发展、环境和农产品安全构成了很大的威胁。但是,我国当前土壤学几乎忽视了这一土壤学范畴的研究领域。土传植物病原微生物功能明确,是研究土壤微生物区系和生物多样性与功能、土壤微生物与植物生长、土传病原微生物与拮抗微生物等关系的理想研究对象。土壤学在揭示土传病原微生物的生长规律、控制土传病原微生物数量、发挥拮抗微生物的作用、防治作物土传病害等方面具有独特的优势。深入认识土传病原微生物适宜生长的土壤环境是防控作物土传病原微生物生长,实现农药使用量零增长的基础。解决当前严重的作物土传病害不仅是土壤学的责任和义务,而且可以极大地推动土壤学的发展。 相似文献
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尽管我国从1983年就开始禁用有机氯农药，但环境中仍有大量残留存在。土壤中污染物的残留是吸附、降解和迁移等各种理化作用和生物作用的综合结果，其中降解是制约其残留量的关键过程。大量研究表明，影响土壤中农药降解的主要环境因素包括土壤有机质、土壤温度、土壤pH和土壤含水量等，因为这些因素显著影响着土壤微生物的数量和活性。微生物代谢所需的营养物质有一部分来自农药和土壤有机质，土壤中微生物对其降解起着重要作用。胡敏酸（HA）是土壤有机质的主要组分，因此以HA代表土壤有机质对农药降解的影响是合理的，也有很多关于HA对农药在土壤中吸附等环境行为影响的研究报道。 相似文献
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甲基对硫磷对红壤地区土壤微生物数量的影响 总被引：4，自引：0，他引：4
有机P农药是我国最重要一种农药类型,在农业生产上使用广泛。采用室内模拟方法,研究了甲基对硫磷对红壤地区不同类群土壤微生物数量的影响。研究结果表明,甲基对硫磷对土壤微生物数量的影响随甲基对硫磷添加的浓度、微生物类群和培养时间的不同而变化。添加100 mg/L和500 mg/L浓度甲基对硫磷能明显增加土壤细菌的数量,细菌数量的最大值出现在第10天左右;低浓度甲基对硫磷对土壤微生物数量影响不大。平板混合菌体培养实验证明,甲基对硫磷通过抑制或者杀灭某些种类土壤细菌,从而大大促进土壤生态系统中部分种类细菌数量的增殖。 相似文献
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有机磷农药污染土壤的微生物降解研究进展 总被引：4，自引：1，他引：3
有机磷农药是目前我国使用量最大的农药之一,严重污染环境和生态系统,并通过食物链在生物体内富集,进而危害人类健康。微生物降解技术具有降解效率高、代谢途径多、无二次污染的优势,是目前清除环境中有机磷农药的主要手段,能有效降低有机磷农药的危害。目前有机磷农药的降解微生物主要是通过实验室纯培养方法获得,与自然生态环境中存在的降解功能性微生物信息差异较大,而利用不可培养方法识别功能性微生物的技术具有广阔的应用前景。本文从有机磷农药的使用情况及引发的环境问题出发,概述了有机磷农药在土壤中的迁移转化途径,稳定同位素探测技术和磁性纳米材料等不可培养方法对有机磷农药降解功能性微生物的识别,微生物降解有机磷农药污染土壤的功能基因、降解途径及降解机理;探讨了植物–微生物联合修复在有机磷农药污染土壤修复中的作用,并分析了环境因子及农药自身性质对有机磷农药降解的影响;最后,讨论了微生物降解技术存在的问题及今后研究方向。 相似文献
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黄玉源 《广西农业生物科学》1990,(4)
对质地不同的叶片受 SO_2伤害后组织症状观察表明:(1)叶片厚度变化革质叶最小,纸质叶居中,肉质叶最大。(2)叶肉细胞色泽革质叶为褐色,纸质叶为黄绿色或黄褐色,肉质叶淡灰色。(3)细胞壁变形程度革质叶小,纸质叶居中,肉质叶最大。(4)胞间隙增大是纸质叶比革质叶大,肉质叶反而缩小。(5)质壁分离现象革质叶最明显,纸质叶和肉质叶相似,都不如革质叶明显。(6)叶绿体变形是革质叶最大,纸质叶、肉质叶次之。(7)革质叶的叶脉受害最轻、纸质叶次之,肉质叶最重。 相似文献
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首次在苏铁类植物中发现导管 总被引：10，自引：0，他引：10
本研究通过对鳞秕泽光铁的羽片进行离析观察和电镜观察,发现其木质部中具有导管,导管类型有６种,其中环纹、螺地管为单穿孔板、梯纹、孔纹、网纹等导管为复穿孔板。这是首次在苏铁类植物中发现导管,对于植物学多门学科领域具有极为重要的意义。 相似文献
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以苏北盐城弶港镇滩涂围垦土壤为研究对象,进行了重金属Cr、Pb、As、Cd、Hg的测定及其风险评价,为我国沿海滩涂种植业的发展提供依据,并为其他国家和地区相关研究提供参考。结果表明,该区域土壤中5种重金属含量均未超过《国家土壤环境质量标准》（GB15618—1995）一级标准限制,农田土壤Cr、As、Cd含量较高,郊区菜地土壤Pb、Hg含量较高;重金属Cr、Pb、As、Cd含量在不同土地利用类型间存在显著性差异;Hg含量差异不显著。采用地积累指数法进行评估可知,土壤没有受到单项重金属污染。依据内梅罗综合指数法评估可知,潮间带沉积物、工业区土壤、滩涂围垦熟化的土壤没有受到重金属污染;郊区菜地与农田土壤的污染等级已达到警戒线,污染水平属于＂尚清洁＂。Hakanson潜在生态风险评价结果表明,区域内土壤重金属处于无风险等级,尚不具有潜在生态风险。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(17-18):1753-1767
Abstract Individual peach [Prunus persica (L.) Batsch] trees were monitored prior to the development of peach tree short life (PTSL) to determine if nutrient deficiencies and/or imbalances were causative factors in PTSL development. Twig concentrations of Al, Ca, Fe, K, Mg, Mn, P, and Zn were determined in March and December of each year. In the final year of the study, elemental concentrations were also determined in April after visual symptoms of PTSL were evident. Elemental concentrations in healthy trees were compared to concentrations in trees which eventually died due to PTSL. Significant differences in P and K concentrations between PTSL and healthy trees were found in 1986 and 1987 but no consistent trends were apparent. The greatest differences between PTSL and healthy trees were found after visual symptoms of PTSL appeared. In most cases, elemental concentrations were greater in trees exhibiting PTSL symptoms than in healthy trees. The data indicate that differences were symptoms of the PTSL complex and not a cause in the development of the disease. 相似文献
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农田飞虱种类及其灯下群落结构的初步研究 总被引：1，自引：0，他引：1
张永强 《广西农业生物科学》1989,(4)
本文报道了广西农田飞虱科种类30属56种(同翅目),其中29种广西尚未记载。稻田区的主要种群是褐稻虱(Nilaparvata lugens),白背飞虱(Soga-tella furcifera),灰飞虱(Laodelphax striatellus)和稗飞虱(Sogatella longi-furcifera),蔗田区的主要种群是甘蔗扁飞虱(Eoeurysa flavocapitata)和中华扁飞虱(Perkinsiella sinensis),灯下飞虱群落结构成分主要由褐稻虱和白背飞虱种群组成,次为稗飞虱、褐背飞虱(Opiconsiva nigra),黑边黄脊飞虱(Toya pro-pinqua neopropinqua),拟褐飞虱(Nilaparvata bakeri)和伪褐飞虱(Nilapa-rvata nuiri)。灯下飞虱群落多样性指数以 9月份最高,数量以 7月份最大,群落的多样性与均匀度是极显著正相关,与优势集中性指标是显著或极显著的负相关 相似文献
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T. G. Dobrovol’skaya A. V. Golovchenko O. S. Kukharenko A. V. Yakushev T. A. Semenova L. A. Inisheva 《Eurasian Soil Science》2012,45(3):273-281
The number, structure, and physical state of the microbial communities in high-moor and low-moor peat bogs were compared.
Distinct differences in these characteristics were revealed. The microbial biomass in the high-moor peat exceeded that in
the low-moor peat by 2–9 times. Fungi predominated in the high-moor peat, whereas bacteria were the dominant microorganisms
in the low-moor peat. The micromycetal complexes of the high-moor peat were characterized by a high portion of dark-colored
representatives; the complexes of the low-moor peat were dominated by fast-growing fungi. The species of the Penicillum genus were dominant in the high-moor peat; the species of Trichoderma were abundant in the low-moor peat. In the former, the bacteria were distinguished as minor components; in the latter, they
predominated in the saprotrophic bacterial complex. In the high-moor peat, the microorganisms were represented by bacilli,
while, in the low-moor peat, by cytophages, myxobacteria, and actinobacteria. The different physiological states of the bacteria
in the studied objects reflecting the duration of the lag phase and the readiness of the metabolic system to consume different
substrates were demonstrated for the first time. The relationships between the trophic characteristics of bacterial habitats
and the capacity of the bacteria to consume substrates were established. 相似文献
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Alison W. Watts Thomas P. Ballestero Kevin H. Gardner 《Water, air, and soil pollution》2008,189(1-4):253-263
Polycyclic aromatic hydrocarbons (PAHs) were measured in two wetland plant species grown outdoors in pots of sediment contaminated with up to 730,000 μg/kg total PAHs. After approximately 3 months, the plants were harvested, cleaned, and analyzed for an expanded suite of PAHs which included both the 16 priority PAHs and 22 alkyl PAH homologs. Sediment and air samples were also collected and analyzed. PAH compounds were detected in all of the samples, with the highest concentrations in the contaminated sediment. The root sample concentrations were generally about one order of magnitude lower than that of the sediment, and were strongly correlated with the concentration in the sediment in which they were grown. The concentrations in foliage were much lower and did not correlate with sediment concentration. Concentrations of low molecular weight PAH compounds detected in the foliage were not significantly lower in plants grown in control sediments, suggesting that the sediment is not the primary source of these PAHs. Several high molecular weight PAHs were detected only in plants grown in contaminated sediment. Plants of both species grown in control sediment were larger than plants grown in contaminated sediment. 相似文献
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黑龙江省海伦市农田土壤重金属分布特征及污染评价 总被引：12，自引：4，他引：8
海伦市是以农业为主导产业的黑龙江省县级市,为了解该市土壤重金属时空分布特征及其污染现状,对农田耕层及亚耕层土壤中Cd、Cr、Cu、Ni、Pb、Zn、Hg和As等重金属全量进行了分析,并采用单因子污染指数法和Nemerow综合污染指数法分别对土壤的重金属污染状况进行了评价。结果表明,该地区土壤重金属含量较低,总体表现为西南和西北含量较高、西部含量高于东部的空间分布特征。以松嫩平原土壤元素背景值为标准进行评价,已出现一定程度的污染。以GB15618-1995土壤环境质量标准二级标准进行评价,综合污染指数为0.504,所有样点土壤重金属均未达到污染水平。与耕层土壤相比,亚耕层土壤Hg和Cd含量显著下降,其他元素含量及分布特征则与耕层相似。从1980年到2008年,随着时间的变化,该区域土壤重金属含量增加趋势不明显,近期土壤出现重金属污染风险较小。 相似文献
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Adult white suckers were collected from four lakes in Maine that ranged in pH from 7.0 to 5.4. The gastrointestinal tract and remainder of the carcass of fishes of similar age and size from each lake, and gills from additional fishes of similar size, were analyzed for Al, Cd, Pb, and Zn. Carcasses were also analyzed for Hg. Concentrations of Al, Cd, and Pb were highest in the gastrointestinal tract and lowest in the carcass; Zn concentration was highest in the gill. For carcass, all metals except Al differed significantly among lakes, for gill tissue Cd and Pb differed, and for gastrointestinal tract, only Cd differed among lakes. Where differences were significant, patterns among lakes were similar in each tissue analyzed. Concentrations of Cd, Hg, and Pb were negatively correlated with lake water pH, acid neutralizing capacity (ANC), Ca, and lake:watershed area, and positively correlated with lake water SO4, indicating that concentrations were higher in fish from more acidic lakes. Zinc concentrations in gills were unrelated to lake acidity, and carcass concentrations were higher in the less acidic lakes, which is the opposite of the pattern for the other metals studied. Zinc in gastrointestinal tract did not differ among lakes. Although the lakes we studied were located in undisturbed watersheds and did not receive any point source discharges, fish metal concentrations were comparable to or higher than those reported from waters receiving industrial discharges. 相似文献
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江苏省如皋市土壤中量元素含量有效性评价 总被引：2，自引：1，他引：1
为平衡施肥提供依据,本文应用GPS定位技术采集了江苏省如皋市290个代表性土样,并对土样中钙、镁、硫、硅4种中量元素有效态含量进行了检测和评价。结果显示,全市土壤交换性钙、交换性镁、有效硫和有效硅平均含量分别为4 570、403、26和144 mg/kg。如皋市土壤交换性钙、镁含量丰富,但在各土系土壤间分布不均。有效硫和有效硅同时存在缺乏和过高现象。整体来看,有近1%的土壤缺硅,约14%的土壤缺硫。土壤交换性镁和有效硅的含量为中等变异,交换性钙和有效硫的含量属于高度变异。相关分析显示,4种中量元素有效性与土壤pH、有机质、全氮、有效磷和速效钾含量存在不同程度的相关性。如皋市土壤中量元素有效性不仅与成土母质关系密切,同时受土壤理化性状以及肥料施用的重要影响。今后中量元素肥料的施用应考虑多种因素,以实现平衡施肥。 相似文献