The Rapid Improvement Effect of Deep Tillage Combined with Organic Fertilizer on Fertility Quality of Tobacco Planting Soil in Baoshan

The effect of tillage depth combined with the application of organic fertilizer on the rapid improvement of tobacco soil fertility was studied in 2020. Three tillage depths (S1: tillage depth at 10 cm; S2: tillage depth at 20 cm; S3: tillage depth at 30 cm) and two types of organic fertilizers (OF: commercial organic fertilizer, FM: farmyard manure) were set in a field experiment. Effects of different treatments on soil physical structure, nutrient content and soil enzyme activities were explored in a single growth season. The results showed: (1) Tillage depth combined with the application of organic fertilizer had no significant effect on soil physical structure. The interaction effects of tillage depth×organic fertilizer type can benefit soil organic matter content in the 0-20 cm and 20-40 cm soil layers. S3FM can significantly increase the content of soil organic matter, total nitrogen and nitrate nitrogen in the 0-20 cm soil layer, and the content of soil organic matter in the 20-40 cm soil layer. (2) The interaction effects of tillage depth×organic fertilizer had significant effects on urease activity in the 0~20 cm and 20-40 cm soil layers. Compared with S1OF, S1FM treatment significantly increased the sucrase activity in 0-20 and 20-40 cm soil layers by 41.75% and 14.29%. When the type of farmyard manure was fixed, compared with other treatments, the activity of urease reached the highest significance level at the depth of 30 cm, and the increase was as high as 57.89%. (3) The comprehensive evaluation of soil fertility quality showed that S3FM had the highest soil quality scores in 0-20 cm (0.58) and 20-40 cm (0.74) soil layers, respectively. Therefore, tillage depth at 30 cm combined with organic fertilizer could achieve the purpose of improving tobacco planting soil fertility of Baoshan in a single growing season.