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991.
测土配方施肥应用软件研究与开发 总被引:1,自引:0,他引:1
在实施国家级测土配方施肥项目的实践基础上,将专业知识和电脑编程技术完美结合起来,研发出了一款非常适用的作物测土配方施肥专家。该软件集测土配方施肥数据库建立与维护、测土配方公式自定义与测试、精准配方施肥计算、施肥建议卡和土样测定评价表定制与填充、采样地块信息归类汇总统计、批量作业等功能于一体。阐述了该软件产生的背景、目的和意义、软件特点、主要特色功能以及主要功能模块应用。 相似文献
992.
实施精准农业是促进农业可持续发展的有效途径,而变量施肥是精准农业的核心.介绍了一种基于养分平衡法的变量施肥决策支持系统的功能及其组成,并将气候条件考虑到参数的确定中,初次利用气候条件确定其中一个参数-"目标产量",从而使施肥量更加合理.系统综合考虑了气候条件对目标产量的影响,比传统的以地定产法更贴近实际;以ASP.NE... 相似文献
993.
The aim of this study was to determine the effects of different long‐term management options on re‐establishment of traditional species‐rich grassland in a Lolio‐Cynosuretum grassland. The experiment was set up in 1987 in a low‐fertilized mown pasture in the Eifel Mountains (Germany). Two and four cuts per year each with three levels of nitrogen fertilizer application were compared to no application of P and K fertilizer. Biomass production increased as a result of N application, whereas crude protein content and digestibility of organic matter improved in the four‐cut treatments. During a 20‐year period, we found a significant shift in dominant grass species without any significant effect on species richness. Lolium perenne and Elytrigia repens were replaced by Holcus lanatus and Alopecurus pratensis, especially in the two‐cut treatments with N application. In the unfertilized plots, several individuals of Platanthera bifolia appeared when swards were cut only twice per year, probably as a result of nutrient depletion together with low cutting frequency. An increase in number of cuts mainly supported plant species well adapted to intensive management, even under low N application and relatively low plant‐available P content in the soil. Therefore, we conclude that cutting frequency was a key driver on plant species composition in this experiment. The re‐establishment of traditional species‐rich grassland from intensively managed Lolio‐Cynosuretum was not achieved within 20 years of cutting management combined with absence of P and K application. 相似文献
994.
施肥对湿地松中龄林生长及土壤的影响 总被引:3,自引:0,他引:3
为了促进湿地松中龄林的生长,以湘北9年生湿地松为研究对象,研究了配方肥不同施肥量对湿地松生长、土壤的影响及成本效益。施肥后3年的结果表明:不同施肥处理的胸径、树高、单株材积、林分蓄积生长量及施肥效益均不同程度高于对照,以700 g/株对湿地松生长的促进作用最大;施肥后2年的土壤养分比施肥前有所改善,不同土层土壤pH值降低,有机质、速效K含量均有所提高,速效N含量大幅提高,上层增加量高于下层,速效P不同程度减小,上层减少量低于下层;适量施肥可促进豆马勃菌的生长,施肥后7个月,豆马勃子实体个数在100~800 g/株范围内总体随施肥量的增加而增加。对湿地松中龄林进行1次追肥,能提高单位面积产量和效益,以N、P、K配方肥700 g/株最佳。 相似文献
995.
为探究配方施肥对香蕉植株生物量、各器官养分积累量及养分积累规律,对巴西蕉施肥后,彻底刨根、分解取样研究,得出香蕉生物量及各元素含量。结果表明:配方肥处理各元素吸收大小规律为K>Si>N>Ca>Mn>Mg>P>Fe>Zn>B>Cu。与常规施肥相比,配方施肥可增加香蕉生物量约69.47%,平均每株可增加N、P、K、Ca、Mg、Mn、Fe、Cu、Zn、B、Si约75.98%、63.71%、5.07%、49.39%、82.85%、26.60%、76.24%、44.49%、152.50%、162.22%、81.18%。配方施肥能有效促进植株生长,提高果实和叶片养分积累,为科学制定香蕉养分综合管理技术提供参考。 相似文献
996.
Laxmi Raja Vara Prasad 《Communications in Soil Science and Plant Analysis》2018,49(12):1401-1417
Temporal variation of rice growth and nitrogen (N) uptake generally follow a sigmoid curve and may respond positively to the N-fertilizer application at critical growth stages. In this study, it was hypothesized that the amount of N-fertilizer applied at critical growth stages possibly follows a geometric pattern such as line, parabola, and sinusoidal to attain maximum yield and nitrogen use efficiency. To test and identify the best pattern, short-term modeling-field testing-long-term modeling strategy was followed. The patterns with the highest simulated yield and nitrogen use efficiency from short-term modeling were tested in the field. Finally, long-term evaluation of N-fertilization patterns was performed using 25 years of historical weather data, resulting in the line pattern with 14% more yield and 25% less NO3? leaching in comparison to the conventional N-Fertilization pattern. Therefore, line pattern may be adopted to enhance the yield and nitrogen use efficiency in rice. 相似文献
997.
998.
999.
Ewa Błońska Marek Pająk Stanisław Małek Kazimierz Januszek 《Communications in Soil Science and Plant Analysis》2017,48(6):692-704
The aim of the present research was to study the long-term effect of serpentinite fertilization with additional nitrogen, phosphorous, and potassium fertilizers on some physicochemical properties and the enzyme activity of acidic soils and needle chemistry in stands of Norway spruce (Picea abies (L.) Karst.). Experimental plots were located in spruce stands in the middle forest zone (900–950 m) on two nappes of the Carpathian flysch: Magura and Silesian. Serpentinite was introduced in autumn 2008 on all plots while the other fertilizers in spring 2009. The effect of fertilization was visible mainly in the humus horizon. No significant changes were found in the deeper mineral soil. The acidity and Al toxicity in the surface horizon were ameliorated through serpentinite fertilization. Five years after fertilization, no significant difference in the fertilization treatments was noted in the chemistry of the spruce needles. 相似文献
1000.
【目的】探究有机、无机肥配施对黄梁木Neolamarckia cadamba幼林生长的影响。【方法】采用林地现场小区试验法,对黄梁木幼林进行猪粪、鸡粪、过磷酸钙和氯化钾配施正交试验。【结果】有机、无机肥配施能显著促进黄梁木幼林树高和地径生长,造林半年后,与未施肥相比,施肥处理树高和地径分别增加23.53%~109.41%和37.99%~149.06%;多因素方差分析显示,猪粪和过磷酸钙对黄梁木树高和地径生长有显著影响,其不同水平间差异显著,而鸡粪和氯化钾主效应不显著;综合考虑黄梁木生长状况和肥料成本,选择猪粪14 kg·株-1+过磷酸钙1.5 kg·株-1作为黄梁木幼林施肥方案;回归分析得出,猪粪(x1)和过磷酸钙(x2)施用量与黄梁木树高(yH)和地径(yD)之间的回归方程分别为:yH=1.016+0.031x1+0.221x2(R2=0.835,P=0.000),yD=26.193+0.991x1+6.052x2(R2=0.83,P=0.000)。【结论】有机、无机肥配施能显著促进黄梁木幼林树高和地径生长,当黄梁木施用猪粪14 kg·株-1+过磷酸钙1.5 kg·株-1时,促进作用最为明显。 相似文献