Reduced root water uptake of summer maize grown in water-repellent soils simulated by HYDRUS-1D
Soil water repellency (SWR) is an ubiquitous soil property, that has major effects on surface and subsurface water flow, soil erosion, and therefore also affects plant growth and development. Soil water repellency has been recently observed to decrease summer maize growth, especially when the initial persistence of soil water repellency was high. However, mechanics implicated in maize biomass limitations are still unclear due to limited field observations and measurements of plant water use. This research aims to explain the possible mechanisms that impede the growth of summer maize in water repellent soils by examining soil water content, soil water evaporation and root water uptake (RWU) and comparing the measurements to simulations using HYDRUS-1D. Data from five increasing levels of SWR (CK, WR1, WR2, WR3 and WR4) from a two-year experiment were used. The soil hydraulic parameters described with the van-Genuchten model were calibrated inversely based on the observed volumetric soil water content at 26, 47 and 68 days after sowing (DAS) in 2016 and validated by water content values on 33, 62 and 91 DAS in 2017. The results showed the daily and cumulative RWU values ranked in an order of CK > WR1 > WR2 > WR3 > WR4. The RWU rates and cumulative RWU decreased with an increase of initial water droplet penetration time (persistence), which indicated weaker RWU ability of summer maize in the water repellent treatments. Thirty days after sowing, higher evaporation was observed in water repellent soils compared to CK. Weak RWU of summer maize grown in the water repellent soils and strong soil water evaporation were found. This research demonstrates the possible mechanisms that impede summer maize growth in water repellent soils could include weak RWU and high evaporation.... [Show full abstract]
Keywordssoil water repellency; root water uptake; HYDRUS-1D; volumetric soil water content; Agronomy & Agriculture
Fields of Research0503 Soil Sciences; 0703 Crop and Pasture Production; 05 Environmental Sciences; 06 Biological Sciences; 07 Agricultural and Veterinary Sciences
- Metadata-only (no full-text) 
© 2021 Elsevier B.V. All rights reserved.
Showing items related by title, author, creator and subject.
Rennie, Hamish; Lomax, Adrienne J.The interface of traditional town planning and the “new” environmental planning is potentially problematic and this is especially apparent in the integrated and sustainable use of water resources in Canterbury. It is easy ...
Modelling water allocation in community irrigation using multi-agent system : A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University Chiewchan, Kitti (Lincoln University, 2021)Insufficient water for irrigation is a common problem in New Zealand, particularly in the Canterbury region, where the use and demand have been steadily increasing over the past 20 years (PCE, 2004; The Parliamentary ...
Heiler, Terence David (Lincoln College, University of Canterbury, 1981)For large areas of New Zealand that suffer from agricultural drought, the only practicable way of providing irrigation is through the use of water harvesting schemes that divert winter flood water in nearby streams into ...