Objective  Considering the problems of high salinity, large spatial difference of soil nutrients, extensive management and low benefit in the reclamation area of abandoned salt pan on the South Bank of Laizhou Bay, the precise delineation method of management zones is performed, so as to facilitate the differential fertilization management of farmers and improve the improvement level of saline soil.

  Method  The typical plot of reclamation area of abandoned salt pan was taken as the research region. Site-specific management zones were identified based upon the traditional statistics, principal component analysis and fuzzy c-means classification, and the appropriateness and availability of management zones were evaluated.

  Result  The average soil salt content in the study area reached 1.73 g kg⁻¹, which was at the level of mild salinization. The contents of soil organic matter, total nitrogen, alkali hydrolysable nitrogen, available potassium and available phosphorus were at a low level. Total phosphorus and cation exchange capacity were at a moderate level. Total potassium and pH value reached a high level. The coefficient of variation of total potassium and pH value was less than 0.1, which was a weak variation. The other soil properties belonged to medium variation. The results of principal component analysis showed that the 10 soil attributes could be divided into three principal components. There were great differences in the spatial distribution of soil attributes. The cluster analysis results showed that the study area can be divided into two management zones, and significant differences in soil salt content, organic matter, soil nutrients and other attributes were observed in these two management zones.

  Conclusion  The management zones of farmland in the reclaimed area of abandoned salt pan can be determined by fuzzy c-means classification using different soil attributes. The research results can provide scientific basis and theoretical guidance for the field management of the reclamation area of abandoned salt pan on the southern coast of Laizhou Bay.