生物竹炭改良崇明滩涂盐渍化土壤的试验研究

采用小白菜温室盆栽试验方法,研究了生物竹炭对盐渍化土壤的修复和对小白菜生长及其品质的影响。试验共设4个处理:对照、有机肥、生物竹炭、有机肥+生物竹炭。结果表明:生物竹炭有效降低了土壤的电导率,有机肥显著提高了土壤的电导率,生物竹炭与有机肥配施对土壤电导率无影响;生物竹炭使土壤中的总碳、有机质提高,促进了有效磷、速效钾的释放,降低了土壤总可溶性氮的含量,尤其使铵态氮、硝态氮含量显著降低,但土壤酸碱性和含水率无明显变化;生物竹炭处理显著提高了小白菜的株高、生物量和可溶性糖含量,降低了可食用部分的硝酸盐含量。盆栽试验结果显示,生物竹炭具有改良盐渍化土壤、促进小白菜产量增加和品质提高的作用。

Effects of Bamboo Biochar on Coastal Saline Soils of Chongming Island, Shanghai

A greenhouse pot trial was conducted to evaluate the changes in salinity and other physicochemical properties of soil, and biomass and quality of pakchoi after bamboo biochar additions. Four treatments, bamboo biochar, organic fertilizer, organic fertilizer plus bamboo biochar and control(no fertilizer or biochar added), were employed. The electrical conductivity(EC) of soil was decreased significantly by bamboo biochar amendments, but increased by organic fertilizer. Organic fertilizer plus bamboo biochar did not significantly affect EC. Applying bamboo biochar significantly increased the total carbon content, organic matter, available phosphorus and available potassium in soil. On the contrary, biochar additions significantly decreased total soluble nitrogen, especially ammonium nitrogen and nitrate nitrogen. Soil pH and moisture did not vary among treatments. Bamboo biochar profoundly increased pakchoi height, biomass and soluble sugar contents, and improved its overall quality, but significantly decreased nitrate concentration in edible parts. These results show that applying bamboo biochar could improve coastal saline soil and in turn increase pakchoi yield and quality.