Abstract:

To explore the restoration effect of fallowing on the soil quality of degraded vegetable fields, a three-year positioning experiment was carried out on eight fallowing measures which included direct fallowing without removing the greenhouse, direct fallowing after removing the greenhouse, rotary tillage fallowing after removing the greenhouse, deep ploughing fallowing after removing the greenhouse, deep ploughing fallowing with rice husk after removing the greenhouse, deep ploughing and covering fallowing after removing the greenhouse, deep ploughing and planting green manure fallowing after removing the greenhouse and deep ploughing with lime after removing the greenhouse. The changes in soil quality indicators during different fallowing processes were dynamically observed. The results showed that all the above eight fallowing measures could reduce the contents of water-soluble salts, exchangeable acids, available phosphorus and available potassium in the soil to varying degrees, and increase soil organic carbon, water-stable aggregates, microbial biomass carbon, alkali-hydrolyzable nitrogen, pH value and cation exchange capacity. Except for the direct fallowing without removing the greenhouse, all other fallowing measures could reduce soil bulk density, but all fallowing measures had a relatively small impact on total nitrogen, total phosphorus and slow-release potassium in the soil. Research suggested that the most suitable fallowing measures for restoring the soil quality of degraded vegetable fields included deep ploughing after removing the greenhouse and planting green manure, deep ploughing with rice husks after removing the greenhouse, and deep ploughing with lime after removing the greenhouse. Deep ploughing after removing the greenhouse and covering, as well as deep ploughing after removing the greenhouse, also had good effects. The effects of rotary tillage after the greenhouse was removed and direct fallowing after the greenhouse was removed were relatively small.

Key words: degraded vegetable fields, fallowing measures, remove the shed, deeply ploughing, cover, apply rice husks, green manure, lime