Fertilizer applied to fields today will pollute water for decades
by Victoria Van Cappellen.
A new University of Waterloo study shows that fertilizer applied today will continue to pollute water for decades, creating health risks like “blue baby syndrome” and environmental dead zones in rivers and oceans.
The study, published this week in a special issue of the journal Environmental Research Letters by Waterloo Professor Nandita Basu and doctoral student Kim Van Meter, presents the first direct evidence of a large-scale nitrogen legacy across the United States’ Mississippi River Basin.
“A large portion of the nitrogen applied as fertilizer has remained unaccounted for the last several decades,” said Basu, a professor jointly appointed to the Faculties of Science and Engineering. “The fact that nitrogen is being stored in the soil means it can still be a source of elevated nitrate levels long after fertilizers are no longer being applied.”
Similar to phosphorus, nitrogen is a nutrient for plants and when applied as fertilizer helps increase crop yields. But to maximize these yields, an excess of fertilizer is often applied, leaving large amounts of nitrogen remaining in soil.
Since the 1970s, farmers and policymakers alike have worked hard to reduce the amount of fertilizer leaching from agricultural fields to groundwater and nearby lakes and streams. Yet in some rural areas, nitrate levels in groundwater have been found to be more than ten times the drinking water standard.
Basu and her group analyzed long-term data from over two thousand soil samples throughout the Mississippi River Basin and found a systematic accumulation of nitrogen 25 to 100 centimetres beneath the soil surface. They calculated this accumulation accounts for as much as 50 per cent of net nitrogen inputs.
“We hypothesize that this accumulation occurred not only because of the increased use of fertilizers, but also increases in soybean cultivation and changes in tillage practices over the past 80 years,” says Van Meter.
Their modeling results suggest that this nitrogen legacy could still be leaching into waterways more than three decades after nitrogen is no longer being applied to fields.
“The presence of this legacy nitrogen means it will take even longer for best management practices to have a measurable benefit,” says Basu, also a member of the Water Institute. “If we’re going to set policy goals, it’s critical we quantify nitrogen legacies and time lags in human impacted landscapes.”
Basu and other researchers at the University of Waterloo are currently exploring nitrogen legacies in the Grand River Watershed in Southern Ontario, as well as across North America and at a global scale.
#AskAPharmacist: Managing fevers and colds
This is the latest in a series of posts from the School of Pharmacy celebrating Pharmacist Awareness Month.
Fevers can be unpleasant, especially for parents of young children. Pharmacist Nardine Nahkla shares some guidelines for fever management.
Does vitamin C really help you fight colds? Dr. Kelly Grindrod answers at the #AskAPharmacist playlist.
More pharmacy questions and answers are coming next Thursday.
Gender Equity Dialogue event set for Thursday
This Thursday at 5:00 p.m. in St. Paul's University College's Alumni Hall a community-powered forum will meet to discuss key issues around gender equity.
According to organizers, the Gender Equity Dialogue is the first event as part of The Dialogue Xchange in the spirit of tackling the lack of engaged dialogue in the region.
The event brings together Waterloo thought leaders, change-makers, pioneers, students, professors and community members among many others (a diverse demographic of participants!) to discuss all things Gender Equity in the community; from LGBTQ perspectives, rape culture, equity in the workplace and in media to equity across cultures, parenting and family.
The event is being held in support of the HeforShe movement at the University of Waterloo, as part as the HeforShe 10x10x10 initiative.
Velocity Foundry changes and other notes
The Velocity Foundry, an incubation space opened in 2014, is gone, but its spirit will live on, according to a recent Velocity blog post:
"The emergence of Velocity hardware companies like Pebble, MappedIn and BufferBox was part of the driving force behind the opening of the Foundry, just down the street from the existing Velocity Garage," says the Velocity announcement. "It housed a number of successful companies like TritonWear, Smarter Alloys, and Avidbots, amongst others. When Google moved out of the Tannery, we recognized an opportunity to build a better community by expanding the Velocity Garage, and closing the Foundry. Over the last few weeks, Foundry companies made the block-long migration to their new desks, within the 36,711 square feet of space that makes up the expanded Velocity Garage, North America’s largest free startup incubator. In addition to a new wet lab, assembly space, fitness room, and gym, there will be room for up to 120 startups to work."
Researchers from the Faculty of Arts will participate in a panel discussion tonight that will cover Canada’s history of refugee reception, refugees in limbo abroad, and local settlement challenges and opportunities.
Speaking will be:
- Marlene Epp, professor of history and peace & conflict studies
- Suzan Ilcan, professor of sociology and global governance
- Lamees Al Ethari, professor of English
The Government of Canada recently reached its initial goal to bring 25,000 Syrian refugees to this country, and have just announced a target of 55,800 refugees in Canada by the end of 2016. This panel will offer insight and understanding of the humanitarian and personal issues associated with these commitments.
Moderating the discussion will be Douglas Peers, dean of the Faculty of Arts.
The event takes place at 7:00 p.m. in the Kitchener Public Library Auditorium.
The Velocity Fund 5K qualifier events take place this week, as students with innovative ideas make their pitches to qualify for the the Velocity Fund Finals on March 31. The pitch competitions take place Wednesday and Thursday from 7:00 p.m. to 10:00 p.m. in QNC 0101.
Here's today's Nutrition Month "Myth vs. Fact" supplied by Health Services Nutritionist Sandra Ace:
Myth: Some sugars are better for you than others.
Fact: All sugars contain similar amounts of energy, about 50 to 60 calories per tablespoon/15mL. While natural sweeteners like honey and maple syrup may be tastier and more aesthetically pleasing, the small amounts allowed as part of healthy diet recommendations don’t make a significant nutrient contribution. Since excess added sugar is linked to many conditions, including obesity, heart disease, diabetes, elevated cholesterol, cancer and tooth decay, limit your intake regardless of the sweetener you choose.
The Canadian Heart and Stroke Foundation recommends limiting added sugars from any source to no more than 10 per cent of your total caloric intake. For a 2000 calorie diet, this would be a limit of 12 teaspoons of sugar or other sweetener per day. The World Health Organization takes this a step further and recommends that limiting added sugar to less than 5 per cent of daily total calories may have additional health benefits. This would be 6 teaspoons based on a 2000 calorie intake. If you are checking a label for sugar, 4 grams is equal to about one teaspoon.