Professor, University of Waterloo. Linking hydrologic and biogeochemical processes in agricultural systems and wetlands with climate & management. Knitter.

Joined March 2011
414 Photos and videos
Pinned Tweet
See what we do in the Biogeochemistry Lab! youtube.com/watch?v=9Z5_QGxv… (Thank you @JaninaH2O for putting this amazing video together!)

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H! The UTRCA is also working with controlled drainage, as is ABCA. We also have some results! DM me and we can connect!
16 Nov 2025
Replying to @Shawridgefarm
Shawn, I just read your post asking for controlled drainage and sub-irrigation data. Dr. Merrin Macrae @merrinm was involved in a collaboration in ON and QC about a decade ago. Here's a report, although Merrin will likely have others to share: ouranos.ca/en/projects-publi…
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Dr. Merrin Macrae retweeted
Finding Balance Through Agricultural Water Futures, Merrin Macrae is working together with farmers, government, and industry to navigate the challenges of feeding the world while protecting freshwater ecosystems. Read more: bit.ly/4bqUVKw
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Dr. Merrin Macrae retweeted
How do our unique perspectives and backgrounds shape our understanding of catchment hydrology? How do your study catchment size and climate region affect your knowledge? Contribute to mapping the knowledge landscape of early-career researchers! #CatchmentHydrology
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A poem From @MelLuymes 😂 Beneath the earth, it stands so still, Measuring the water's will. A quiet gauge, a subtle eye, Tracking the levels, low or high. In wells it peers, in soil it sees, The hidden flow, the groundwater's keys. A piezometer whispers truths with ease.
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Potential phosphorus mobilization from riparian vegetation following freezing - New article here! doi.org/10.1016/j.jenvman.20… @Alex_Koiter @JaninaH2O @UWaterloo @OMAFRAinnovates @uofg @GWFutures @AWF_Research

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Climate Change will change flowpaths in Ag, increasing subsurface runoff and dissolved nutrient losses - New paper doi.org/10.1016/j.jglr.2024.… @AWF_Research @GWFutures @Lake_Futures @nanditabasu2 @UWaterloo

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Dr. Merrin Macrae retweeted
Managing #phosphorus in agricultural fields is important for maintaining #WaterQuality Here are some ways that Dr. Merrin Macrae suggests ensuring phos stays in the soil, where it’s needed: 🌾Apply Phos at the right rate & draw down soil levels of phos in areas where they are noted to be elevated 🌾Apply fertilizers containing phos using subsurface application methods & gently incorporate manures instead of broadcasting 🌾It’s best to apply phos at the time of seeding & never on frozen ground To learn more about targeting #BestManagementPractices that will have the greatest impact on water quality, check out this webinar from Dr. Merrin Macrae and Dr. Catherine Febria. youtube.com/watch?v=mCFp93fS…
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Dr. Merrin Macrae retweeted
16 Sep 2024
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Dr. Merrin Macrae retweeted
Great time working with great #phosphorus people at #IPW10. Good job 👍 🙏@JamesHuttonInst @H2oHutton @CarriProject 🏴󠁧󠁢󠁳󠁣󠁴󠁿
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Dr. Merrin Macrae retweeted
Post wheat cover crops are starting to green up! UTRCA has funding for cover crops at $30/ac. Contact us to apply!
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Dr. Merrin Macrae retweeted
Wayne Rouse was a driving force on my committee during my MSc and PhD. He cared deeply about Canada’s north, climate change, and everyone he met. Much of his work was ‘pre internet’ and now overlooked. Looking back, Wayne was far ahead of the curve in every way. Remember him.
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Dr. Merrin Macrae retweeted
We are hiring an Agricultural Stewardship Specialist to support our team in the delivery of projects that reduce erosion, improve water quality, increase soil health and/or create habitat.
We're #hiring a new position with our @UTRCAsoilwater team! The Agricultural Stewardship Specialist will work with landowners, farmers, and partners, providing agronomic expertise and supporting agricultural research. 🌿 Learn more and apply by July 21: thamesriver.on.ca/about-us/c…
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Dr. Merrin Macrae retweeted
Simulating hydrological behaviour of tile drains to understand the impacts of climate or land management change on agricultural surface and subsurface runoff: lessons from Ontario hess.copernicus.org/articles… #CRHM @GWF_pubs @AWF_Research @merrinm
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Field tour selfie! @UTRCAsoilwater @LTVCA
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Dr. Merrin Macrae retweeted
CRAZY wind and hail in the core of this near Shelburne #onwx #onstorm @StormhunterTWN @alluringstorms
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Dr. Merrin Macrae retweeted
27 Feb 2024
#Struvite application to #corn decreases the risk of environmental #phosphorus loss while maintaining crop yields relative to readily soluble #fertilizers. Our new open access article... #runoff #soil #agronomy #OntAg #waterquality sciencedirect.com/science/ar…
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Dr. Merrin Macrae retweeted
Apply NOW for cost-share funding to start cover cropping, improve N management or expand rotational grazing on your farm. Visit ontariosoilcrop.org #OntAg #ONFarmClimateActionFund
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Dr. Merrin Macrae retweeted
Inside #WaterResearch Issue 18 | Learn more about spatial economic optimization of best management practices to reduce Phosphorous loadings into #LakeErie. An insightful analysis considering both public programming costs and private farm-level costs. bit.ly/42MEpQI
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