Applying geostatistics to determine the soil quality improvement by Jerusalem artichoke in coastal saline zone

The plant growth characteristics are spatially variable due to inherent variability in soil properties and other parameters of the landscape. In the study, the plot size in the field was 670 m in length (south-north direction), and 70 m in width. The stem height and diameter were measured in October, and tuber yield was evaluated in December 2012. The salt content of 0-5, 5-10 and 10-20 cm depth of soil was measured. The morphological characteristics and normal distribution test were analyzed by descriptive statistics using Matlab. The collaborative kriging interpolation and the distribution of spatial heterogeneity of related parameters were analyzed using GS+ software. Soil salt content increased with increasing soil depth. At the same soil depth, the salt content was higher in the north than the south part. The root fresh weights, tuber number, stem height and diameter of Jerusalem artichoke were relatively larger in the north than the south. The distributions of tuber fresh weight and tuber number in space were similar. The Pearson correlation coefficient between tuber fresh weight and tuber number was up to 0.70. Jerusalem artichoke's morphological characteristics were directly related to soil salt content. Inherent variability of position and soil properties could strongly influence the morphological characteristics of Jerusalem artichoke.