土壤调理剂对土壤养分含量及微生物功能多样性的影响

以湖南典型红土为供试土壤,以烤烟品种K326为材料,通过小区试验,探究了土壤调理剂对土壤养分含量及微生物功能多样性的影响。结果表明,土壤调理剂改变了土壤养分,土壤p H、有机质含量、速效钾含量、有效磷含量均显著提高,而碱解氮含量无显著性差异;适量添加土壤调理剂可显著提高土壤微生物平均吸光值,过量添加反而降低,土壤微生物平均吸光值高低依次为T2T1T3CK;添加0.2%土壤调理剂可以显著提高微生物功能多样性丰富度指数和均一性指数,较对照分别提高了5.1%、88.4%;主成分分析结果显示,添加土壤调理剂使土壤微生物群落对碳源的代谢特征产生了差异。综合而言,添加适量的土壤调理剂能增加土壤养分含量,提高土壤微生物群落功能多样性,以0.2%的添加量最佳。

Effects of Soil Conditioner on Soil Nutrient Content and Microbia Functional Diversity

Taking the typical laterite in Hunan Provice and tobacco variety “K326” as experimental material, this paper explored the effects of soil conditioner on soil nutrient content and microbia functional diversity through a plot experiment. The results showed that soil conditioner could change the soil nutrient, soil pH, and significantly increase the contents of organic matter, available phosphorus, and available potassium. While there was no significant difference in alkaline nitrogen content. It was found that the AWCD (average well color development) value was remarkably increased when adding the soil conditioner at a proper weight percent. However, the AWCD value could decline when too much soil conditioner was applied. The order of soil microbial AWCD values was T2＞T1＞T3＞CK. The activities of species richness and McIntosh index were increased significantly at the application rate of 0.2%, the enzyme activities were increased by 55.1%, 88.4% than that of the CK, respectively. The result of principal component analysis showed that the diversities and the carbon utilization ability of soil microbial community had a lot of discrepancies by using soil conditioner. All in all, proper addition of soil conditioner could increase soil nutrient content, and improve the soil microbial functional diversity. The most appropriate application rate was 0.2%.