生物黑炭对酸化茶园土壤的改良效果

采用田间试验,研究施用生物黑炭0(CK)、8、16、32、64t.hm-25个水平对酸化茶园土壤的改良效果。结果表明,施用不同用量的生物黑炭处理与CK处理相比,0～20cm土层土壤pH值提高0.19～1.72个单位,土壤交换性酸降低0.79～3.96cmol.kg-1,土壤盐基饱和度提高20.98%～173.67%,土壤阳离子交换量增加0.80～2.46cmol.kg-1;20～40cm土层土壤pH提高0.05～0.61个单位,土壤交换性酸降低0.20～2.14cmol.kg-1,土壤盐基饱和度提高27.72%～56.51%,土壤阳离子交换量增加0.57～1.12cmol.kg-1。土壤改良效果随生物黑炭施用量的增加而增大,且对0～20cm土层土壤的改良效果大于20～40cm土层土壤。施用生物黑炭各处理春茶鲜叶产量分别为CK的106.61%、105.62%、99.89%和99.23%,各处理及与CK间差异均不显著(P>0.05)。

Ameliorating Effect of Biochar on Acidity of Tea Garden Soil

Ameliorating effect of biochar in varying concentrations(i.e.,0,8,16,32 and 64 t hm-2) on acidity of tea garden soils were studied in field trials.The results showed that,as compared with CK(no added biochar),the soil pH increased by 0.19-1.72,the soil exchangeable acid decreased by 0.79-3.96 cmol·kg-1,the soil base saturation increased by 20.98-173.67%,and the soil cation exchange capacity(CEC) increased by 0.80-2.46 cmol·kg-1 on the 0-20 cm layer of the soils.On the other hand,in the 20-40 cm layer of the soils,the pH of the treatment samples increased by 0.05-0.61,the soil exchangeable acid decreased by 0.20-2.14 cmol·kg-1,the soil base saturation increased by 27.72-56.51%,and the soil CEC increased by 0.57-1.12 cmol·kg-1.It appeared that the soil ameliorating effect increased with increasing biochar addition.The increase was particularly significant in the 0-20 cm than the 20-40 cm layer of the soils.The yield of the fresh tea leaves was changed 6.61%,5.62%,-0.11% and-0.77% by the addition of biochar at the rates of 8,16,32 and 64 t·hm-2,respectively.However,no significant differences(P>0.05) on tea yields between the treatments and control was found.