Investigating the relationships between soil and sugarcane attributes under different row spacing configurations and crop cycles using the state-space approach

The adoption of different row spacing configurations has been advocated as a possible solution to mitigate the problems related to soil compaction in sugarcane areas due to the frequent use of heavy agricultural machines. This study aimed to (i) identify factors that influence the relationships of biometric attributes of sugarcane and attributes of an Oxisol soil under different scenarios in Southern Brazil and (ii) describe the distribution of the biometric attributes of sugarcane through state-space analysis under all the evaluated scenarios. Sugarcane was planted using conventional planting systems. The total experimental area of 200 m x 20 m consisted of three row spacing configurations: (i) single-row spacing; (ii) double-row spacing; and (iii) triple-row spacing. In each row spacing configuration, a transect was established, and fifty soil sampling points were distributed at equal distances. At each point and transect, disturbed and undisturbed soil samples were collected in the 0.00-0.10 m soil layer to determine soil bulk density, total porosity, macro- and - microporosity, soil penetration resistance and water content at field capacity in three sugarcane crop cycles. At the end of each crop cycle and each transect, stalk height, number of stalks per square meter, stalk mass and tons of stalks per hectare were determined at each sampling point. All the data sets were analyzed using descriptive statistics and ANOVA. In addition, using the Tukey test, the mean values of each attribute were compared to assess the effects of each row spacing configuration and sugarcane crop cycle on all the soil and crop attributes. Spatial relationships of the biometric attributes of sugarcane and co-regionalized soil attributes under each row spacing and crop cycle were evaluated using the auto- and cross-correlation functions and the state-space approach. There were no statistically significant differences between the crop and soil attributes measured under the single- and double-row spacing configurations. In addition, it is expected that with the advance in the age of the sugarcane crop, a superiority of the performance of the double-row spacing, compared with the single-row spacing, will be observed, due to the possibility of monitoring the traffic control under the double-row spacing configuration. On the other hand, the adoption of the triple-row spacing configuration caused negative effects on all the crop and soil attributes, compared with the other two row spacing configurations. Future studies of sugarcane crop and soil attributes should be developed to validate the state-space approach in other environmental conditions.

Automated summary

The study found no significant differences in crop and soil attributes under single and double row spacing configurations, but with the advancement in age of sugarcane crop, a potential superiority in performance of the double row spacing over single row spacing was observed. Adoption of the triple row spacing configuration caused negative effects on all crop and soil attributes.