关键词: 重度盐碱地改良, 土壤特征, 植物光和, 植物生长

Abstract: Though studying the ameliorated influence of Saline-alkali soil’s soil properties, photosynthesis and growth of different plants, we found that, after Saline-alkali ameliorations, soil properties significantly changed. The soil total porosity was 5% to 20% higher than control (bare land); field capacity was increased by 3%~13%; soil bulk density from the control of 1.2~1.4 g·cm^-3 down to 0.7~1.0 g·cm^-3; soil compaction in control 2 000~2 500 kPa reduced to 500~1 000 kPa; soil capillary rise height and soil permeability rate were also higher than control; soil conductivity reduced by an average 1 288 μs·cm^-1; soil pH value averagely decreased 1.5; shallow groove and deep groove treatments respectively improved nitrogen by 50% and 100%; shallow groove and deep-groove treatments improved soil CO₂ concentrations 2 500~3 500 μL·L^-1 and 3 000~3 500 μL·L^-1; Deep-groove treatment dropped the soil oxygen concentration to about 17%. The photosynthetic capacity of plants had been increased; Glycyrrhiza uralensis, Zea mays and Sabina chinensis var. sargentu in the deep-groove treatment were increased by 2.5~12 μmol·m^-2·s^-1. There were obviously improvements in biomass, including Z.mays, Brassica oleracea, Raphanus sativus and S.chinensis var. sargentu, etc. The deep groove treatment was much higher than the others. It was proved the requirement of these plants to high soil organic matter. The biomass differences of Medicago sativa, G.uralensis, Beta vulgaris var. saccharifera and Iva xanthifolia in different ameliorations were not obvious. Our finding indicted the ideal plants for large-scale Saline-alkali soil amelioration should fully consider soil condition and plant adaptability.

Key words: Saline-alkali soil amelioration, soil characteristics, photosynthesis of plants, growth of plants