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Susilawati Kasim Osumanu Haruna Ahmed Nik Muhamad Ab. Majid Mohd Khanif Yusop Mohamadu Boyie Jalloh 王艳群 孙志梅 《腐植酸》2011,(2):30-34
腐殖质中的腐植酸和黄腐酸可以提高土壤中可交换性铵(NH4+)的回收率。这两种酸固定和保持NH4+的能力已经在许多研究中得到了证实,二者通过提高植株的光合作用速率、促进根系发育影响植物的生长和养分吸收。因此,本研究调查了这两种酸(液态)对玉米干物质产量、土壤铵态氮和硝态氮(NO3-)含量的影响。根据液态有机氮肥的组成,采用标准方法分离提纯腐植酸。有机氮肥在玉米种植后第10天、第28天分别施入盆栽土壤,然后在种植后第54天或孕穗期采集植株和土壤样品。土壤样品分析PH、铵态氮和硝态氮含量,植株样品测定干物质产量。结果表明,在酸性条件下,液态有机氮肥(黄腐酸、腐植酸或二者同时施用)的施用可以提高土壤中NH4+的累积量。随土壤活性碳储量的增加,腐植酸分子上羧基官能团对土壤NH4+的吸附能力增强。然而,酸含量较低时对干物质产量的影响明显减小。各处理间硝态氮的有效性没有达到统计上的差异显著水平。较低的PH值能抑制土壤硝化作用进程,同时降低土壤NO3-含量。这表明液态腐植酸和/或黄腐酸在提高尿素利用效率方面发挥着重要作用。然而,与腐植酸分子特性有关的作用机理还需要进一步详细研究。本研究为液态和叶面有机肥料的发展提供一定的依据。 相似文献
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为推广缓控释肥在玉米上的应用,进行了控释尿素和普通尿素不同掺混比例的复混肥对玉米肥效的试验。结果表明,玉米施用控释氮比例为40%的控释氮肥时,玉米产量及其构成因素、叶面积、种植效益较高。 相似文献
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为明确不同氮肥类型在玉米上的施用效果,采用大田试验,研究了尿素、多元素长效碳铵颗粒肥等生产上常用氮肥对玉米产量、光合速率、叶面积指数和氮肥效率等的影响.结果表明:不同氮肥类型增产达2418.5~3639.4 kg/hm2,其中,施用尿素增产最大;但施用多元素长效碳铵颗粒肥的相对纯收入最高,每公顷达4352.9元.尿素和多元素长效碳铵颗粒肥处理的玉米叶片硝酸还原酶、叶片SPAD、叶面积指数、光合速率和氮素积累均高于其他氮肥类型;尿素和多元素长效碳铵颗粒的氮肥利用率、氮肥农学利用率和氮肥偏生产力也显著高于其它氮肥类型.综上所述,考虑到提高玉米产量,缓解土壤酸化现象以及增加农民相对纯收入等因素,推荐多元素长效碳铵颗粒肥作为研究区域氮肥品种更为适宜. 相似文献
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J.M. Kimetu D.N. Mugendi C.A. Palm P.K. Mutuo C.N. Gachengo A. Bationo S. Nandwa J.B. Kungu 《Nutrient Cycling in Agroecosystems》2004,68(2):127-135
Decline in crop yields is a major problem facing smallholder farmers in Kenya and the entire Sub-Saharan region. This is attributed mainly to the mining of major nutrients due to continuous cropping without addition of adequate external nutrients. In most cases inorganic fertilizers are expensive, hence unaffordable to most smallholder farmers. Although organic nutrient sources are available, information about their potential use is scanty. A field experiment was set up in the sub-humid highlands of Kenya to establish the chemical fertilizer equivalency values of different organic materials based on their quality. The experiment consisted of maize plots to which freshly collected leaves of Tithonia diversifolia (tithonia), Senna spectabilis (senna) and Calliandra calothyrsus (calliandra) (all with %N>3) obtained from hedgerows grown ex situ (biomass transfer) and urea (inorganic nitrogen source) were applied. Results obtained for the cumulative above ground biomass yield for three seasons indicated that a combination of both organic and inorganic nutrient source gave higher maize biomass yield than when each was applied separately. Above ground biomass yield production in maize (t ha–1) from organic and inorganic fertilization was in the order of senna+urea (31.2), tithonia+urea (29.4), calliandra+urea (29.3), tithonia (28.6), senna (27.9), urea (27.4), calliandra (25.9), and control (22.5) for three cumulative seasons. On average, the three organic materials (calliandra, senna and tithonia) gave fertilizer equivalency values for the nitrogen contained in them of 50, 87 and 118%, respectively. It is therefore recommended that tithonia biomass be used in place of mineral fertilizer as a source of nitrogen. The high equivalency values can be attributed to the synergetic effects of nutrient supply, and improved moisture and soil physical conditions of the mulch. However, for sustainable agricultural production, combination with mineral fertilizer would be the best option. 相似文献
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在25℃静水释放试验条件下,对2种控释BB肥的控释性能进行了研究。结果表明:2种控释BB肥对养分均有一定的控释性能,对氮素的控释效果最好,磷、钾控释效果较差。两种控释BB肥相比,控释BB肥1对氮的控释效果优于控释BB肥2,而控释BB肥2对磷、钾的控释效果优于控释BB肥1。 相似文献
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再论“人口·粮食·环境·肥料” 总被引:5,自引:0,他引:5
依据我国经济高速增长、社会进步及饮食结构变化,讨论了我们人口与粮食的关系,饮食结构对国家粮食安全以及畜禽业发展与施肥对环境的影响.介绍了我国农田生态系统N、P2O5、K2O、S、Ca和Mg的养分平衡.在S、Ca、Mg养分平衡中,过磷酸钙、钙镁磷肥起到了重要作用.在小麦基肥和玉米追肥中,碳铵、硝铵均优于尿素.探讨了缓释、控释肥用于超级玉米、超级水稻种植的可能性. 相似文献
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对最近几年我国氮肥主要品种、尿素产量、进出口及表观消费量进行了分析 ,指出 2 0 0 0年氮肥供大于求的格局不会有大的改变。通过对影响化肥价格因素的探讨 ,分析了 2 0 0 0年化肥市场启动的有利因素和不利条件 ,结论是 2 0 0 0年化肥市场启动难度大 ,但在有利因素促使下 ,化肥市场有可能好于去年 相似文献
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Liming Yang Jake C. Fountain Hui Wang Xinzhi Ni Pingsheng Ji Robert D. Lee Robert C. Kemerait Brian T. Scully Baozhu Guo 《International journal of molecular sciences》2015,16(10):24791-24819
Drought stress decreases crop growth, yield, and can further exacerbate pre-harvest aflatoxin contamination. Tolerance and adaptation to drought stress is an important trait of agricultural crops like maize. However, maize genotypes with contrasting drought tolerances have been shown to possess both common and genotype-specific adaptations to cope with drought stress. In this research, the physiological and metabolic response patterns in the leaves of maize seedlings subjected to drought stress were investigated using six maize genotypes including: A638, B73, Grace-E5, Lo964, Lo1016, and Va35. During drought treatments, drought-sensitive maize seedlings displayed more severe symptoms such as chlorosis and wilting, exhibited significant decreases in photosynthetic parameters, and accumulated significantly more reactive oxygen species (ROS) and reactive nitrogen species (RNS) than tolerant genotypes. Sensitive genotypes also showed rapid increases in enzyme activities involved in ROS and RNS metabolism. However, the measured antioxidant enzyme activities were higher in the tolerant genotypes than in the sensitive genotypes in which increased rapidly following drought stress. The results suggest that drought stress causes differential responses to oxidative and nitrosative stress in maize genotypes with tolerant genotypes with slower reaction and less ROS and RNS production than sensitive ones. These differential patterns may be utilized as potential biological markers for use in marker assisted breeding. 相似文献
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固化菌藻系统处理养殖废水中氨氮的研究 总被引:1,自引:0,他引:1
采用海藻酸钠-氯化钙固定法固化硝化细菌和硝化细菌与小球藻的混合物,来处理养殖废水中的氨氮污染,考察了处理时间、温度、p H和氨氮/固化小球用量比对氨氮去除效果的影响。实验结果显示,固化硝化细菌小球和固化菌藻小球均能有效去除废水中的氨氮,但固化菌藻小球的去除效果更佳。在28℃、p H=8、氨氮起始质量浓度为50 mg/L、氨氮/固化菌藻小球用量比为1∶40的实验条件下,24 h内能去除废水中96.51%的氨氮。实验结果证实,硝化细菌和小球藻具有一定的共生关系,在去除氨氮时有协同效应,固化菌藻小球在养殖废水脱氮中具有一定的应用前景。 相似文献