施用生物炭提高酸性红壤茶园土壤的微生物特征及酶活性

Improved soil microbial characteristics and enzyme activities with wheat straw biochar addition to an acid tea plantation in red soil

通过福建安溪茶园的田间试验定位研究不同小麦秸秆生物炭施入量(0、10、20、40 t/hm^2)对红壤茶园土壤性质、土壤微生物和酶活性的影响,阐明生物炭对酸性茶园土壤的改良效应。结果表明,与不施用生物炭相比,40 t/hm^2生物炭施用量处理显著降低茶园土壤容重达0.23 g/cm^3,土壤碱解氮含量下降29.2%,但土壤有机质、有效磷和速效钾分别增加了62.1%、153.9%和173.6%,同时提高土壤p H值0.88个单位。随着生物炭施用量的增加,茶园土壤中细菌、放线菌、真菌、解钾细菌以及解无机磷细菌的数量分别提高了28.5%～104.4%、27.2%～123.4%、17.0%～35.9%、109.2%～208.2%和150.0%～337.3%,β-葡萄糖苷酶、脲酶和碱性磷酸酶活性也显著增加了45.5%～114.7%、8.6%～21.5%和26.7%～186.6%,而土壤酸性磷酸活性却降低了4.0%～15.6%。相关分析表明土壤有效磷含量与解无机磷细菌、碱性磷酸酶活性存在显著正相关关系,速效钾含量与解钾细菌亦存在显著正相关关系,施用生物炭改善酸性红壤茶园土壤的酸碱环境和微生物活性,有利于促进土壤养分转化。

Biochar have been applied as soil ameliorant to improve soil quality and microbial activity.However,the effect of biochar on soil characteristics and microbial activities in acidified tea plantation in red soil is still not well understood.Therefore,a field experiment was carried out to study the effects of wheat straw biochar application(0,10,20,40 t/hm^2)on soil chemical characters,microbial properties and enzyme activities of tea plantation in Anxi,Fujian.The results showed as follows:Compared with the control,application of 40 t/hm^2 biochar significantly decreased the soil bulk density by 0.23 g/cm^3 and soil alkaline hygdrolyzable nitrogen content by 29.2%,while significantly increased the soil organic matter,available phosphorus,and available potassium content by 62.1%,153.9%and 173.6%,respectively.Likewise,soil pH increased by 0.88 units.As the amount of biochar amendment increasing,the numbers of bacteria,actinomycetes,fungi,potassium dissolving bacteria and phosphate-solubilizing bacteria significantly increased by 28.5%~104.4%,27.2%~123.4%,17.0%~35.9%,109.2%~208.2%and 150.0%~337.3%in the tea plantation,respectively.Meanwhile,application of biochar significantly increased the activities ofβ-Glucosidases,urease and soil alkaline phosphatase by 45.5%~114.7%,8.6%~21.5%and 26.7%~186.6%,respectively,but decreased the activity of acid phosphatase by 4.0%~15.6%.Therefore,biochar is an effective amendment to improve soil properties and soil nutrients condition in acid tea plantation soil in red soil.