<p style="text-align:justify;"> <b><span>Background:</span></b><span> The objective of this study was to determine the short-term effect of urea fertiliser application on ...<p style="text-align:justify;"> <b><span>Background:</span></b><span> The objective of this study was to determine the short-term effect of urea fertiliser application on soil reactions in a Ferralsol, with particular thrust on P sorption. </span><b><span>Methods:</span></b><span> Two experiments were conducted for this purpose</span><span>:</span><span> </span><span>1</span><span>) a screenhouse pot experiment</span><span>;</span><span> and </span><span>2</span><span>) a laboratory P sorption component. The pot (10 litre capacity plastic pots) experiment was conducted at the Makerere University Agricultural Research, Kabanyolo in Uganda, using a Ferralsol. The study comprised of four urea N (46% N) fertiliser treatments, namely, 0, 40, 80 and 120 kg N·ha</span><sup><span style="vertical-align:super;">-1</span></sup><span>, equivalent to 0, 200, 400 and 600 mg N per pot. A completely randomised design was adopted with three replicates. Urea rates were applied in 50% split doses, one at planting and the other at 19 days after seedling emergence (to simulate farmer practice). This was followed by watering to field capacity using distilled water. Soil samples were taken at three daily intervals until day fourteen;thereafter, soil sampling was at an interval of seven days. The second urea split dose was applied at 21 days followed by soil sampling at </span><span>an </span><span>interval of three days till day fourteen. Thereafter, soil was sampled at seven day intervals until the end of experi</span><span>ment. Soil samples were analysed for exchangeable H</span><sup><span style="vertical-align:super;">+</span></sup><span>, Al</span><sup><span style="vertical-align:super;">3+</span></sup><span>, NH<sub>4</sub><sup style="margin-left:-9px;">+</sup></span><span>and</span><span> NO<sub>3</sub><sup style="margin-left:-9px;">-</sup> </span><span>ions. The reaction trends of the concentrations of these ions and Bray 1 P were used to structure different response curves representing the instantaneous reactions. As for the 展开更多
在城市生活垃圾进行工厂化堆肥过程中,加入难溶性磷矿粉,探讨堆肥对难溶性磷的转化能力及堆肥产品培肥后对土壤磷素吸附特性的影响。结果表明,加入磷矿粉可使堆肥中活性有机磷、中等活性有机磷、中稳性有机磷、高稳性有机磷及速效磷含...在城市生活垃圾进行工厂化堆肥过程中,加入难溶性磷矿粉,探讨堆肥对难溶性磷的转化能力及堆肥产品培肥后对土壤磷素吸附特性的影响。结果表明,加入磷矿粉可使堆肥中活性有机磷、中等活性有机磷、中稳性有机磷、高稳性有机磷及速效磷含量均有不同程度的提高,与对照相比分别增加212.69%、80.36%、61.21%、62.74%、157.89%。通过电镜观察表明,堆肥后磷矿粉典型的矿物特征消失,表面呈蜂窝状。将堆肥后的产品进行培肥试验表明,富磷垃圾肥处理可明显改善土壤磷素的吸附特性,与施化肥相比,最大吸附量(Qm)下降8.76%,最大缓冲容量(Qm.K)下降13.58%,而磷素的吸附饱和度(D P S)、零净吸附浓度磷(EP C0)则呈不同程度的增加,幅度依次为98.52%、7.13%。试验结果显示,通过堆肥生产富磷垃圾肥可为解决中国磷素资源缺乏、化学磷肥利用率低等问题提供一条生物学途径。展开更多
文摘<p style="text-align:justify;"> <b><span>Background:</span></b><span> The objective of this study was to determine the short-term effect of urea fertiliser application on soil reactions in a Ferralsol, with particular thrust on P sorption. </span><b><span>Methods:</span></b><span> Two experiments were conducted for this purpose</span><span>:</span><span> </span><span>1</span><span>) a screenhouse pot experiment</span><span>;</span><span> and </span><span>2</span><span>) a laboratory P sorption component. The pot (10 litre capacity plastic pots) experiment was conducted at the Makerere University Agricultural Research, Kabanyolo in Uganda, using a Ferralsol. The study comprised of four urea N (46% N) fertiliser treatments, namely, 0, 40, 80 and 120 kg N·ha</span><sup><span style="vertical-align:super;">-1</span></sup><span>, equivalent to 0, 200, 400 and 600 mg N per pot. A completely randomised design was adopted with three replicates. Urea rates were applied in 50% split doses, one at planting and the other at 19 days after seedling emergence (to simulate farmer practice). This was followed by watering to field capacity using distilled water. Soil samples were taken at three daily intervals until day fourteen;thereafter, soil sampling was at an interval of seven days. The second urea split dose was applied at 21 days followed by soil sampling at </span><span>an </span><span>interval of three days till day fourteen. Thereafter, soil was sampled at seven day intervals until the end of experi</span><span>ment. Soil samples were analysed for exchangeable H</span><sup><span style="vertical-align:super;">+</span></sup><span>, Al</span><sup><span style="vertical-align:super;">3+</span></sup><span>, NH<sub>4</sub><sup style="margin-left:-9px;">+</sup></span><span>and</span><span> NO<sub>3</sub><sup style="margin-left:-9px;">-</sup> </span><span>ions. The reaction trends of the concentrations of these ions and Bray 1 P were used to structure different response curves representing the instantaneous reactions. As for the
文摘在城市生活垃圾进行工厂化堆肥过程中,加入难溶性磷矿粉,探讨堆肥对难溶性磷的转化能力及堆肥产品培肥后对土壤磷素吸附特性的影响。结果表明,加入磷矿粉可使堆肥中活性有机磷、中等活性有机磷、中稳性有机磷、高稳性有机磷及速效磷含量均有不同程度的提高,与对照相比分别增加212.69%、80.36%、61.21%、62.74%、157.89%。通过电镜观察表明,堆肥后磷矿粉典型的矿物特征消失,表面呈蜂窝状。将堆肥后的产品进行培肥试验表明,富磷垃圾肥处理可明显改善土壤磷素的吸附特性,与施化肥相比,最大吸附量(Qm)下降8.76%,最大缓冲容量(Qm.K)下降13.58%,而磷素的吸附饱和度(D P S)、零净吸附浓度磷(EP C0)则呈不同程度的增加,幅度依次为98.52%、7.13%。试验结果显示,通过堆肥生产富磷垃圾肥可为解决中国磷素资源缺乏、化学磷肥利用率低等问题提供一条生物学途径。
