生物质灰渣等对红壤性状的影响

Influence of biomass ash as a kind of soil amendment on acidity and fertility of red earth

为评估生物质灰渣等改良剂对红壤酸度的改良效果,通过土壤培养实验研究了生物质灰渣、磷灰石和石灰3种改良剂对红壤酸度的改良效应。结果表明,3种改良剂均能提高土壤p H和降低土壤交换性Al3+含量,其中,生物质灰渣在培养前期表现差异明显,随着培养时间延长,实验设定的生物质灰渣用量对土壤p H的影响差异不明显;石灰和磷灰石用量对土壤p H和土壤交换性Al3+含量影响显著。培养期间,添加改良剂后土壤p H保持上升趋势,且p H增幅随改良剂用量增加而增加。3种改良剂的施用均可提高土壤CEC和土壤交换性钙含量,用量为4500 kg·hm-2时达到最大值,生物质灰渣处理土壤CEC提高0.90 cmol·kg-1,土壤交换性钙提高1.11 cmol·kg-1;磷灰石处理土壤CEC提高2.17 cmol·kg-1,土壤交换性钙提高0.78 cmol·kg-1;石灰处理土壤CEC提高1.85 cmol·kg-1,土壤交换性钙提高3.47cmol·kg-1。生物质灰渣施用提高土壤速效磷和速效钾含量显著,4500 kg·hm-2用量时达到最大值,分别为19.49和225.00mg·kg-1;磷灰石施用提高土壤速效磷含量且随磷灰石用量增加而增加;石灰施用提高土壤速效磷和碱解氮含量。

In order to investigate the influence of soil amendments on the acidity and fertility of red earth soil, soil incubation experiments were conduted using three soil amendments, apatite, biomass ash, and lime. The results indicated that all the three amendments increased soil p H and decreased exchangeable Al3＋ in the order of lime 〉 apatite 〉 biomass ash, with biomass ash only having these effects at the eraly stage of culture. The application rates of lime and apatitie significantly changed soil p H and exchangeable Al3＋ contents. There was a significantly positive relationship between soil p H and the application rates of soil amendments, except for biomass ash, whereas a significantly negative correlation between the application rates of soil amendments and exchangeable Al3＋ was observed. All the three amendments increased cation exchnage capacity（CEC） and soil exchangeable Ca2＋, with the maximum effect reached at the application rate of 4500 kg/hm2. At this optimal rate, compared with the control the application of biomass ash, apatite, and line increased CEC and soil exchangeable Ca2＋ by 0.9 and 1.11 cmol/kg, 2.17 and 0.78 cmol/kg, and 1.85 and 3.47 cmol/kg, respectively. The application of biomass ash increased soil available phosphorus and available potassium, with their maxima 19.49 and 225.00 mg·kg-1, respectively, obtained at the application rate of 4500 kg·hm-2. Apatite increased soil available phosphorus and a positive relationship was observed between the application rate of apatite and soil available phosphorus. Finlly, lime increased alkali-hydrolyzable nitrogen and soil vailable phosphorus.