Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5770920 | Journal of Hydrology | 2017 | 8 Pages |
â¢The free TF is the major pathway of water in the SI and SII phases.â¢The SIII phase presented the highest rates of evaporation and SF on all rainfall events.â¢Evaporation from saturated canopy is the main loss for all storms.â¢IL in sugarcane is higher than maize, coffee, banana and citrus and smaller than soybean.â¢The Gash model reached good performance to simulate IL in sugarcane.
The expansion of sugarcane plantations in Brazil has raised concerns regarding its hydrological impacts. One of these impacts is related to rainfall interception, which can be expected to vary in response to substantial changes in canopy structure throughout the cropping cycle. We collected field measurements to determine interception losses and interpreted the observations using an adapted Gash model during different stages of a sugarcane ratoon cropping cycle. Cumulative gross rainfall (PG), throughfall (TF) and stemflow (SF) were measured biweekly, along with vegetation structure measurements of leaf area index (LAI) and plant height. For the first 300Â days after the first harvest, the cumulative PG of 1095Â mm was partitioned into 635Â mm TF (58%) and 263Â mm SF (24%). The inferred interception loss (IL) was 263Â mm (24%). There was a gradual and clear increase in IL from 3% to 46% while partitioning between TF and SF also changed during ratoon regrowth. After model parameter optimisation, observed IL was simulated satisfactorily. Model estimates suggested that evaporation from the saturated canopy is the main IL pathway, followed by evaporation after storms. Plant architecture, LAI and meteorological conditions during the cropping cycle appeared the main factors determining IL.