| Ten suburbs and two farms of Shanghai, Yangtse delta were choiced for the paper's research, which was 106.7 thousand hm2. Based on technologies of Geography Information System (GIS), Global Position System (GPS) and Geographical Statistical Method, 4087 soil samples were collected and tested, and the spatial differentiation Character of fourteen soil nutrients were studied, and thirty field examinations were completed, optimizing fertilization amount was recommended by means of regional management of specific soil nutrients, which was adopted from Agro Services International Inc (ASI). The conclusions were as follows.1. Based on the study of spatial differentiation character of fourteen soil nutrients in Shanghai, 14 spatial distribution maps of soil nutrients were drawed, which illustrated the influences of different factores (such as soul type, rock types, land use, farming planting system, fertilizer, environment, etc) on spatial differentiation of soil nutrients. Five grades were classified from 1 to 5 to identify the nutrients'criteria from infertile, hypo-infertile, middle, hypo-abundant to abundant. 1 grade expressed that soil nutrients were more infertile, 2 grade expressed that soil nutrients were hypo-infertile, and others were on the analogy of this.2. Soil analysis results indicated that: soil fertility was pertained to the middling level or on the low side mostly. Optimizing fertilization amounts of N,P,K was appropriate for trace elements Mn,Zn, and the pertinence for trace elements S,B was recommended, besides Ca,Mg,Cu,Fe needn't fertilized. Suburbs of Shanghai were compartmentalized to four parts such as the East, middle, west and the island, and fertilizer prescriptions were east(N:P:K:Zn=16:4:4:0.05), middle (N:P:K:Zn=16:6:7:0.05), west (N:P:K:Zn=16:4:5:0.05), and island (N:P:K:Zn=18:4:7:0.05) separately.3. The results of field experimentations were as follows: propositional fertilizer applications on N,P,K were proposed based on ASI. Its N optimum applying amount is 30-60 kg/hm2, and the rice yield was increased inapparently; but the rice yield was reduced apparently with decreasing 30-60 kg N/hm2 . The benefit of rice yield will be increased apparentaly with the increasing of phosphorus and potassium, and the benefit of decreasing the mount of P was less than the benefit of decreasing the mount of K. With the increasing amount of trace elements Mn, Zn, rice yield was increased apparently. The yield of rice which was fertilized by the proposal amount of OPT (9181.3kg/hm2) was 650.1kg/hm2 higher than by the customary amount (8531.2 kg/hm2), and the increasing rate and earning were 8.0% and 1043.6 yuan/hm2 separately. The application amount of recommendation fertilizer could not only increase the economic benefit of rice but also the efficiency of fertilizer use. Compared with the customary fertilization amount, the increased using efficiency were 11.71% (Nitrogen),9.78% (Pohosphorus) and 13.16% (Potassium) separately.4. Rice soil nutrient amount took on vertical distributing rule obviously. Nutrients(N,P,K,S,B,Cu,Fe,Zn)amount of cultivated laye(r0-20cm)were higher than sub-cultivated layer, other nutrients (pH,OM,Ca,Mg,Mn) were lower than that of the cultivated layer. Study on soil nutrient of different soil layers indicated that recommend fertilization amount was took into account mostly by nutrient amount of cultivated layer.It is a signality that the rice yield was increased and the fertilizer's cost was reduced,N,P,K utilization ratio was increased and farmland entironment was improved by means of area specific soil nutrient management, which gained marked economy benefit. This technique has obtained abroad popularizing and application spread all over Shanghai suburb.
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