Effect of rainfall and swath density on dry matter and composition change during drying of switchgrass and corn stover

Abstract

During field drying, crops can be subjected to rainfall losses due to leaching, respiration and mechanical treatments. The objective of this study was to measure the impact of rainfall amount (8 to 75 mm) and crop density (0.8 to 2.6 (corn stover), 1 to 3.2 (switchgrass) kg [DM] m-2) on dry matter and composition change of corn stover (CS) and switchgrass. CS and switchgrass lost 0.3 to 4.7% and 0.2 to 2.8% as leaching loss from 8 to 75 mm of rainfall, respectively. After the incubation period of 48 h, the dry matter loss increased to 7.2 to 9.8% (CS) and 2.6 to 6.1% (switchgrass) from 8 to 75 mm of rainfall, respectively. Water soluble portion of CS and switchgrass was more severely affected than the fibre portion. Corn stover, being more exposed to rainfall in low density (LD) swaths, lost 56.7% ash content, compared to 19% in high density (HD) swaths. In CS, a significant decrease of K (10.2 to 63.8%) and Mg (5.6 to 41.7%) was observed with greater reductions in LD swaths compared to HD swaths. Similarly, a significant decrease in K (6.2 to 23.0%) and Mg (5.1 to 17%) content was observed in switchgrass but it was less prominent than CS.

Modelling the influence of crop density and weather conditions on field drying characteristics of switchgrass and maize stover using random forest

“…Dedicated machines such as tedders are also used to spread the crop evenly on the field which helps to capture maximum solar radiation for rapid drying. However, spreading the crop also exposes it to unfavourable events such as rainfall, which can prolong the field drying period and reduce dry matter and quality of the crop (Khanchi & Birrell, 2017b).…”

Development of the IBSAL-SimMOpt Method for the Optimization of Quality in a Corn Stover Supply Chain

“…Dry matter loss during field drying (variable "DMLOSS") (decimal): Linear regression was performed on the data provided by Khanchi and Birrel [39]. The resulting equation is used to compute the percentage of dry matter lost during the field drying period.…”

“…Windrow density (variable "WindrowDensity") (kg/m 2 ): Khanchi and Birrel [39] evaluate the effect of rainfall and swath density on dry matter, and the composition change during the drying of corn stover. They assume three possible densities 0.8, 1.3, and 2.6 kg/m 2 (low density-LD, medium density-MD, and high density-HD, respectively).…”