论文部分内容阅读
我校实验农场土壤发育于钱塘江河口冲积体上,为河口海陆过渡相母质,1米深土层内已无石灰性反应,旱地为潮土类、潮土亚类、黄松土属、粗粉质黄松土种:水田为水稻土类、潴育型水稻土亚类、黄松田土属、粗粉质黄松田土种。 农场土壤有机质含量多在1.5～2.5％之间:全氮量和速效氮含量均属中等,分别为0.158％和10～20ppml有效磷含量大于15ppm者占全场耕地的90％;速效钾含量低于75ppm者占70％;比五十年代的土壤养分含量已有全面提高。土壤酸碱度已从三十年前以中性和微碱性为主,转变为以酸性为主,甚至出现强酸性±壤(pH低至5.2)。
The soil of experimental farm in our school was developed on the alluvial deposits of Qiantang estuary, which is the transitional parent material of sea-land transition in estuaries. There was no lime reaction in the 1-m deep soil layer. The dry land was composed of alluvial soil, alluvial soil, Pinus tabulaeformis: Paddy soil is paddy soil type, the type of paddy soil subsoil, yellow pine soil, coarse silty pine soil. Soil organic matter content in farms ranged from 1.5% to 2.5%. Total nitrogen content and available nitrogen content were moderate, 0.158% and 10 ~ 20ppml, respectively, accounting for 90% of the total cultivated land; available potassium content was low Accounting for 70% at 75ppm; the soil nutrient content in the 1950s has been fully improved. Soil pH has been dominated by neutral and slightly alkaline three decades ago, changing mainly to acidity and even to strongly acidic pH (pH as low as 5.2).