Friday, March 29, 2019
Room 1528 - 1100 North University Building Map
Two of our prominent challenges for the 21st Century are meeting water resource needs (domestically and agriculturally) while also providing a sufficient food supply in the face of a growing population and a changing climate. On a global basis, groundwater is increasingly being used to meet water needs, and managed groundwater storage is an emerging focus for water agencies. Missed within management plans, however, is an account of water contaminants that may threaten the viability of precious groundwater resources. Owing to the high particle surface area to water volume ratio, which generally runs in near opposition to surface water reservoirs, native contaminants can be particularly problematic. Within the Indo-Gangetic Plain, for example, which supplies water to over a billion people throughout India, Pakistan, Nepal, and Bangladesh, groundwater levels are largely being maintained but more than 55% of the shallow (less than 200 m) aquifer is contaminated with native salt (25%) or arsenic (28%). In nearly every subsurface environment, a naturally occurring metal residing within the soil/sediment may jeopardize water quality if a dissolution/desorption process is stimulated. Recognizing processes by which native contaminants may be released to groundwater and avoiding such reaction conditions is critical for sustaining viable water supplies. Unfortunately, groundwater supplies are not alone in being threatened by native contaminations. Often correlating with groundwater contamination is a second major threat from naturally occurring contaminants, and particularly arsenic: Food production. Of the major cereal crops, rice is uniquely susceptible to reductions in yield and grain quality resulting from soil-borne arsenic. Further exacerbating the impacts of arsenic on rice production are temperature increases that both induce plant stresses and enhance soil microbial activity. The combined impacts of projected temperatures for the year 2100 coupled with soil arsenic endemic to the major rice growing regions of Asia lead to a yield reduction exceeding 40% compared to current conditions. Further, at any soil arsenic concentrations, inorganic grain arsenic levels double for every 5 C change in temperature. In order to sustain future grain production, rice varieties and soil management practices will need to evolve rapidly to minimize the arsenic-temperature impacts.
|Building:||1100 North University Building|
|Event Type:||Lecture / Discussion|
|Source:||Happening @ Michigan from Earth and Environmental Sciences|