采用短期（46 d）室内好气培养方法，研究不同茶枝生物质炭添加量对茶园红壤、黄壤 pH 和氮素净转化速率的影响。生物质炭用量设5个水平：H0（0 t·hm－2）、H1（8 t·hm－2）、H2（16 t·hm－2）、H3（32 t·hm－2）、H4（64 t·hm－2），生物质炭来源为茶树枝条。结果表明：培养结束时，与不添加生物质炭处理相比（H0），添加生物质炭处理均可提高2种茶园土壤 pH 值，红壤增加0．24～1．20个单位，黄壤增加0．26～1．34个单位，pH 提高幅度与生物质炭用量呈正相关。添加生物质炭后显著降低了茶园土壤氮矿化量、净氮矿化速率和净硝化速率（P ＜0．05），特别是 NO－3-N 含量，抑制茶园土壤硝化作用，抑制程度随生物质炭添加量增加而增强。红壤茶园土壤矿质态氮含量、净氮矿化速率及净硝化速率要高于黄壤，黄壤茶园土壤矿质态氮表现为净固持；相同添加量的生物质炭对红壤氮素转化的影响大于黄壤。综上所述，短期培养条件下，生物质炭能显著降低茶园土壤矿质态含量，抑制土壤硝化作用，其抑制效果因生物质炭用量和土壤类型而异。%Effect of biochar addition on pH and nitrogen transformation in the acidic red and yellow soils at tea plantations was studied by an aerobic incubation experiment in the lab. Biochar made from clipped tea branches was added to the soils at a rate of H0(0t·hm-2 ),H1(8 t·hm-2 ),H2(16 t·hm-2 ),H3(32 t·hm-2 ),or H4(64 t· hm-2 ). The results showed that,the pH of the red soil raised 0.24 to 1.20 units and that of the yellow soil raised 0.26 to 1.34 units with the biochar. On the other hand,the nitrogen mineralization,net nitrogen mineralization rate,and net mineralization rate,especially the NO-3 -N content,of the soils were significantly reduced. The nitrification in soil was inhibited by the additions,and the effect was greater with increasing biochar. Since the nitrogen mineralization,and the rates of mineralization of the red soil were higher than those of the yellow soil, which showed a negative net reduction with the biochar additions,it indicated that a same biochar application would result in much greater effection the nitrogen transformation in the red than the yellow soil. It appeared that, depending upon the application rate and the soil type,by incorporating biochar varying degrees of the inhibitory effect on the nitrogen mineralization and nitrification in the plantation soils could be achieved.
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