Bioenergy crops, such as switchgrass (front) and miscanthus (rear), have very dense foliage, thus having a different effect on hydrology than traditional agricultural crops. They transpire more water, thereby reducing both soil moisture and runoff. | Photo by Praveen Kumar “While we are looking for solutions for energy through bioenergy crops, dependence on water gets ignored, and water can be a significant limiting factor,” said Praveen Kumar, the Lovell Professor of civil and environmental engineering at the University of Illinois. “There are many countries around the world that are looking into biofuel energy, but if they are adopting these (large grasses) into their regular policy, then they need to take into account the considerations for the associated demand for water.”
Kumar led a study, published this week in the Proceedings of the National Academy of Science Early Edition, detailing effects to the hydrologic cycle of large-scale land conversion, both now and as growing conditions change in the future.
Miscanthus and switchgrass have a very different above-ground foliage structure from corn – more surface area and much denser growth. This is good for maximizing the amount of biomass that an acre of land can produce, but it also increases water use. Miscanthus and switchgrass intercept light and rain differently from corn, and lose more water through transpiration, causing them to pull more water from the soil. The result of large-scale adoption would be a reduction in soil moisture and runoff, but an increase in atmospheric humidity.
“All these together account for the changes in hydrology, just from land-use change,” said Kumar, who also is affiliated with the department of atmospheric sciences. “Then, if you impose further – higher carbon dioxide in the atmosphere, higher temperatures and changes in rainfall patterns – they add further modulation to the water use pattern.”
Kumar’s group used a sophisticated model it developed to study crops’ fine sensitivities to temperature and carbon dioxide changes in the atmosphere. The model incorporates the acclimation response of plants to changing climate.Using their predictive model, the researchers found that the net water use will increase further as a result of rising temperatures and carbon dioxide. Higher levels of carbon dioxide alone make the plants more water-efficient, since their pores are open less time to absorb carbon dioxide.
However, rising temperatures counteract this effect, as the plants will transpire more while their pores are open, losing more water than they save.
This additional water loss compounds the increase in water usage from land conversion. In the U.S. Midwest, rainfall should remain sufficient to meet water demand, according to Kumar. However, areas that rely on irrigation could find they have less water to meet higher demands, which could increase the net cost of large-scale land conversion and put pressure on already stressed water resources.
“If we’re going to solve energy problems through bioenergy crops, there are collateral issues that need to be considered,” Kumar said. “Water is a significant issue. It’s already a scarce resource across the globe, and the need for it is only going to increase. The cost of that should be factored in to the decision making.”
Graduate student Phong V.V. Le and former postdoctoral researcher Darren Drewry (now at the Max Planck Institute in Germany) were co-authors of the paper.
The National Science Foundation and the Vietnam Education Foundation supported this work.
Liz Ahlberg | University of Illinois
New insight into why Pierce's disease is so deadly to grapevines
11.06.2018 | University of California - Davis
Where are Europe’s last primary forests?
29.05.2018 | Humboldt-Universität zu Berlin
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
19.06.2018 | Physics and Astronomy
19.06.2018 | Life Sciences
19.06.2018 | Physics and Astronomy