基于室内模拟培养试验,研究改良剂(生物质炭、过氧化钙)对旱地红壤微生物量碳、氮及可溶性有机碳、氮的影响。试验设置4个处理,即CK、Ca(过氧化钙,1.72g/kg)、C(生物质炭,21.46g/kg)、C+Ca。结果表明:各处理土壤微生物量碳、氮以及可溶性有机碳具有相同的变化趋势,即前期(3d内)都增加较快,在第3天达到最大值,随试验进行有所下降,配施效果优于单施。各处理可溶性有机氮在21d内缓慢增加;第21天时,C+Ca、Ca、C相比CK分别显著增加了62.1%,55.5%,40.9%;35d以后,配施(C+Ca)与单施过氧化钙(Ca)的效果显著优于单施生物质炭(C)和对照(CK)。120d培养期内,配施(C+Ca)处理能够明显提高微生物量碳、氮以及可溶性有机碳、氮的平均含量;微生物量碳的平均含量大小顺序为C+Ca〉C〉CK〉Ca,微生物量氮的平均含量C+Ca处理显著高于其他处理;可溶性有机碳的平均含量大小顺序为C+Ca〉Ca〉C〉CK,可溶性有机氮的平均含量C+Ca、Ca处理显著高于CK、C处理。微生物量碳、氮以及可溶性有机碳之间互为极显著正相关(P〈0.01),而微生物量碳与可溶性有机氮之间呈极显著负相关。因此,生物质炭和过氧化钙能有效提高旱地红壤微生物量碳、氮及可溶性有机碳、氮,且生物质炭与过氧化钙配合施用更有助于土壤改良。
Based on the indoor simulation experiment,the effects of amendment(biochar and calcium peroxide)on microbial biomass carbon,nitrogen and dissolved organic carbon and nitrogen in upl and red soil were studied.The experiment included 4 treatments,namely CK,Ca(calcium peroxide,1.72g/kg),C(biochar,21.46g/kg), and C+Ca.The results showed that soil microbial biomass carbon,nitrogen and dissolved organic carbon had the same change tendency,which increased rapidly within 3 days, and reached the maximum on the third day, and then decreased with the time.Additionally,the effect of combined application of the two amendments was better than that of single application.The dissolved organic nitrogen increased slowly within 21 days;compared with CK,dissolved organic nitrogen under C+Ca,Ca,C treatments significantly increased by 62.1% ,55.5% , and 40.9% on twenty-first days,respectively;after 35 days,the effects of C+Ca and Ca was significantly better than those of C and CK.During the 120 days incubation period,C+Ca treatment could significantly improve the average content of microbial biomass carbon,nitrogen and dissolved organic carbon and nitrogen;the ranking of average content of microbial biomass carbon from high to low was:C+Ca〉C〉CK〉CCa, and the average content of microbial biomass nitrogen in C+Ca treat-ment was significantly higher than those of other treatments.the ranking of average content of soluble organic carbon was C+CaCaCCK, and they were significantly higher in C+Ca and Ca than those of CK and C.There was a significant positive correlation between microbial biomass carbon,nitrogen and dissolved organic carbon(P〈0.01),but there was a significant negative correlation between microbial biomass carbon and dissolved organic nitrogen.Therefore,biochar and calcium peroxide can effectively improve soil microbial biomass carbon,nitrogen and dissolved carbon and nitrogen in upl and red soil, and the combination of biochar and calcium peroxide is more beneficial to soil improvement