茶园土壤硫素状况及对硫的吸附特性

Sulphur Status and Its Adsorbing Characteristic in Soils of Tea Garden

对江浙皖三省茶园土壤硫含量及其影响因子,土壤对硫的吸附固定特性等的研究表明,茶园土镶有效硫含量在5.4—250.7mg/kg之间,平均为54.1mg/kg,以浙江最高,江苏次之,安徽最低;土壤全硫量在24-453 mg/kg之间,平均为190.5 mg/kg;土壤有效硫占全硫的比例在1.38％-69.1％之间,平均为17.2％。土壤有效硫含量与全硫含量呈极显著正相关,与土壤有机质含量、pH值、成土母质和茶叶产量等均有明显的关系。茶园土壤有效硫含量在过去十年中有较大幅度的降低,平均降幅达32.8％;缺硫土壤的比例也相应由31.2％提高到了46.1％。土壤对硫的吸附固定能力因施硫量和成土母质不同而异,随着施硫量的增加,土壤对SO_4^(2-)的吸附能力逐渐减弱;成土母质间比较表现为第四纪红土>鞍山斑岩>溪流冲积物>红砂岩,加入到土壤中的硫素养分平均有29.9％被吸附固定。

The S contents in tea soils sampled from Zhejiang, Anhui and Jiangsu provinces, its influencing factors and adsorbing characteristics were investigated. The results showed that the available S content in tea soils ranged from 5.4 to 250.7 mg/kg with the average of 54.1 mg/kg. Among the three provinces studied, Zhejiang was the highest and Anhui the lowest. The whole S content was 24-453 mg/kg with 190.5 mg/kg on average. The ratio of available S to whole S was between 1.38% and 69.1% with average of 17.2%. The available S content was of significantly positive correlation to the whole S content, and also closely related with organic matter, pH, parental material and tea productivity, etc. The content of available S decreased by 32.8% in the last decade, resulting in the number of soil with available S content less than 40 mg/kg increased from 31.2% to 46.1%. The capacity of soil adsorption to SO42- varied with the quantities of S applied and its parental materials. The more the S fertilizer added to soils, the less proportion of added S adsorbed. The quaternary red clay showed the highest capacity to adsorb SO42-, about 53.8% of S added was adsorbed, followed by soils derived from slate and rivulet sediment, almost no adsorption to SO42- was observed in red sand soil derived from tertiary red sandstone.