Study on fertility characteristics of central urban park soils in Shanghai

Surface(0~30 cm) and profile(0~90 cm) soil samples of the central urban parks were collected in Shanghai city,pH,EC,organic matter,N,P,K content were analyzed,furthermore,the integrated soil fertility was evaluated by Nemoro index.Results indicated that the soil pH was dominated by slightly alkaline(pH 7.5~8.5)and alkaline(pH8.5),and the soil pH over 7.5 account for 98.74%; But soil EC were relatively low,mainly in 0.03～0.74 mS·cm-1,averaged in 0.13 mS·cm-1;Soil organic matter was dominated by medium level;Soil total N total P and alkali-hydrolyzable N were medium to low level,and most park soils were lack in available P,but total K and available K were relatively rich.The distribution pattern in soil profile were different,soil pH was strong alkaline in the while profile,and had no significant difference;Soil EC was increased along with the increasing of soil layers;The content of organic matter,total nitrogen,alkali-hydrolyzable N,available P,available K were decreased along with the increasing of soil layers,and the content in surface soil were significantly higher than the subsurface and substrate(p0.05).The total P content in surface were higher than the substrata,but had no significant difference.Results by the Nemoro index showed that the integrated soil fertility in central urban park was very low,53.52% soil was in 0.9～1.8,44.65% soil was below 0.9,which means medium to very low fertility level,and need improvement in the future maintaining.