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本文就嘉定区南翔、方泰、马陆及嘉定四镇的大棚、水田、果园及露地土壤的理化性质进行了初步调查与研究。研究表明:嘉定区土壤为粉(砂)壤质,除果园土壤为微酸性外大多呈中性及弱碱性。土壤酸度为果园>水田>露地>大棚,且表层<底层。大棚土壤碱性最强,且电导率较高,碱化度接近5%,有盐碱化的倾向。各处土壤阳离子交换量都处于10～20cmol(+)kg-1之间,属于保肥力中等的土壤,且果园>水田>大棚>露地。该区土壤的含氮量不高,除水田外均低于上海市农田平均水平,而磷和钾含量较高,除露地土壤外均高于市平均水平。总的来说,养分含量为水田>果园>大棚>露地。这些结果都说明:嘉定区农业土壤中,果园和水田土壤理化性状较好,养分含量高。大棚土壤养分含量也十分丰富,但土壤含盐量过高,需引起重视,防止次生盐渍化问题的产生。露地土壤养分含量最低,可以通过施有机肥,实行水旱轮作等措施进行改良。
In this paper, Nanxiang, Fangtai, Malu and Jiading four greenhouses, paddy fields, orchards and open-field soil physical and chemical properties were initially investigated and studied. The results showed that: the soil in Jiading District was silt (sandy) loam, mostly neutral or weakly alkaline unless the orchard soil was slightly acidic. Soil acidity orchard> paddy field> open field> greenhouses, and the surface paddy field> greenhouse> field. The soil nitrogen content in this area is not high, except in paddy fields are lower than the average level of farmland in Shanghai, while the phosphorus and potassium content is higher, except the open field soil were higher than the city average. In general, the nutrient content of paddy field> orchard> greenhouse> open field. These results show that: Jiading District, agricultural soil, orchard and paddy soil better physical and chemical properties, high nutrient content. Greenhouse soil nutrient content is also very rich, but the soil salinity is too high, need to pay attention to prevent secondary salinization problems. Open field soil nutrient content is the lowest, can through the application of organic fertilizer, implementation of measures such as drought and drought rotation to be improved.