Spatial variability and relationships of rice leaf area index and yield

Spatial distributions and relationship between rice leaf area index and yield were analyzed using geostatistical methods. The results show that: (1) Leaf area index and yield are approximately normally distributed; (2) Under the discussing conditions, rice yield and leaf area index during most of developmental stages are spatially structured; (3)Yield and leaf area index during booting stage, heading stage and milk stage are positively correlated across up to 12 m or so and their correlations are considered significant across different distances depending on different developmental stages. The theory of indicator Kriging being used for reference, the method of the indicator value distribution which was proposed in the article was used to analyze the relationships between yield and combined leaf area index obtained from several developmental stages. The method is significant to perform precision farming and estimate rice yield and can be used for reference in studying spatial relationship between one variable and several variables or that between one variable and dynamic distributions of the other one.