城区河岸带植被类型对土壤保持的影响研究

Effects of Urban Riparian Vegetation Types on the Retention of Soil Nutrients

采用调查采样与室内试验分析的方法,研究了城区不同河岸带植被类型对土壤养分保持能力的影响。结果表明:1)城区河岸带植被类型可以较为显著地影响土壤养分含量及其在河岸带0~30cm土层的分布特征。河岸带的结缕草草坪、虎尾草草坪与荒草地、杨树林、火炬树林相比,土壤的全氮、有效氮、全磷、有效磷和土壤有机质含量在0~5cm和5~10cm土层均有显著的降低,而在10~20cm和20~30cm土层的差异则不明显。2)在0~30cm的河岸土壤,河岸的结缕草坪和虎尾草坪的土壤养分平均含量都要小于河岸的荒草地和林地,但2个草坪类型的土壤容重则较大。河岸带5种植被类型的土壤养分保持能力依次为荒草地、杨树林地、火炬树林地、结缕草草坪和虎尾草草坪。

Through the method of sampling and laboratory analysis, this study analyzed the effects of different urban riparian vegetation systems on the retention of soil nutrients. The results showed that （1） ripari- an vegetation types had significant effects on the content of soil total nitrogen （TN）, available nitrogen （AN） ,total phosphorus （TP）,available phosphorus （AP） and soil organic matter （SOM）,and also the vertical distribution characteristics of the soil nutrients in the 0-30 cm soil profile. Compared with riparian abandoned grassland,Rhus typhina forestland and Populus simonii forestland, the content of soil TN, AN, TP, AP and SOM of Chloris virgata lawn and Zoysia japonica lawn significantly decreased in the 0-- 5 cm and 5--10 cm soil layer,but with little effect on the soil layer below 10 em. 2） In the 0--30 cm soil profile, the average content of soil TN, AN, TP, AP and SOM of abandoned grassland,R, typhina forestland and P. simonii forestland was higheer than C. virgata lawn and Z. japonica lawn,but the soil bulk density（BD） exhibited opposite trend. The capacity of soil nutrient retention was the highest under abandoned grass- land, followed by P. simonii forestland, and R. typhina forestland,Zoysia japonica lawn and Chloris virga ta lawn.