南京市中心城区道路绿地土壤肥力调查与评价

采集了南京市中心城区部分主干道路0~20 cm和20~40 cm的绿地土壤,研究其容重、土壤孔隙度、pH、有机质、有效养分含量等理化性质,以了解道路绿地土壤的基本性状。结果表明:南京城市道路绿地表层土壤(0~20 cm)容重大,孔隙度小;pH在7.21~9.00之间,较自然土壤明显偏高,以偏碱性为主;0~20 cm和20~40 cm土壤中,土壤有机质平均值分别为23.6、17.7 g/kg,碱解氮平均值分别为50.493、2.39 mg/kg,基本处于中偏低水平;速效磷平均值分别为24.21、5.1 mg/kg,处于中偏高水平。土壤脲酶活性、碱性磷酸酶活性与土壤有机质和碱解氮含量显著相关(P<0.01),可以作为表征城市绿地土壤肥力的生物指标。

Study on Fertility Characters of Road Greenbelt Soil in Nanjing City

Soil samples with 0～20 cm and 20～40 cm depths of road greenbelt were collected at central district in Nanjing City.Their bulk density,soil porosity,pH,organic matter,available nutrients were studied in this paper.The results showed that surface soil(0～20 cm) had a high bulk density,low porosity.The pH values of soil were 7.21～9.00,dominated by alkaline.In 0～20 cm and 20～40 cm layer,the average contents of soil organic matter were 23.6,17.7 g/kg,and alkali-hydrolyzable N were 50.49,32.39 mg/kg respectively,being in the low level.Whereas available P were 24.2,15.1 mg/kg,being in the high level.Urease and alkaline phosphatase activity had significant relation with soil organic matter and alkali-hydrolysable N,and were biological indicators for fertility of road greenbelt soil.