Characteristics of Temporal-Spatial Variability of Soil Fertility in City Greenbelt Soil of Coastal Saline Soil

Urbanization not only makes land and geographical space a change, but also soil fertility has been a fundamental change. We calculated the membership and weight by using the fuzzy math method, principal component analysis and AHP method. This author analyzed the temporal-spatial variability of soil total salt, pH, nutrient and the soil fertility index in the year of 1998 and 2008 in autumn in TEDA. We found that after 10 years of the soil survey in TEDA the soil total salt decreased markedly; soil available nitrogen, available phosphorus and organic matter increased remarkably; pH decreased slightly, available potassium rised slightly; the soil fertility complex index increased significantly. The main reason for time-varying of soil fertility may be shallow dense type of underground pipe salt drainage engineering and artificial fertilization of scientific manner; the main reason for spatial variation of soil fertility was related to different sources of new soil and filling the zone in different time when the zone was construction built.