Merrin Macrae's guest appearances

Merrin Macrae

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Phosphorus is a key nutrient for crop production, and requires careful management to ensure there’s enough P to feed a growing crop, but not so much that the nutrient moves off the field in run-off or soil movement. For what makes phosphorus management different versus say, nitrogen, we go to experts Dr. Merrin Macrae, professor... Read More

Phosphorus is a key nutrient for crop production, and requires careful management to ensure there’s enough P to feed a growing crop, but not so much that the nutrient moves off the field in run-off or soil movement. For what makes phosphorus management different versus say, nitrogen, we go to experts Dr. Merrin Macrae, professor... <a href="https://www.realagriculture.com/2021/11/the-agronomists-ep-45-jeff-schoenau-and-merrin-macrae-on-managing-phosphorus-losses/" rel="nofollow" target="_blank">Read More</a>

The Agronomists, Ep 45: Jeff Schoenau and Merrin Macrae on managing phosphorus losses

“Winter Phosphorus Release from Cover Crops and Linkages with Runoff Chemistry” with Dr. Merrin Macrae Cover crops can offer a variety of ecosystem services, including reducing soil erosion. However, in colder climates, where cover crops can freeze and die over the winter, there is the possibility that the Phosphorus within cover crops can then leach into surface runoff. Dr. Merrin Macrae and her team decided to dive deep and discover whether or not this trade-off exists and, if so, to what extent. Listen to learn:  What do Nalgene bottles and ping pong balls have to do with research? What is it like to do field research in the winter? How can Twitter lead to working research relationships with farmers? Which factors contribute most to surface P runoff?  If you would like more information about this topic, this episode’s paper is available here: https://doi.org/10.2134/jeq2018.08.0307  This paper is always freely available. If you would like to find transcripts for this episode or sign up for our newsletter, please visit our website: http://fieldlabearth.libsyn.com/ Contact us at podcast@sciencesocieties.org or on Twitter @FieldLabEarth if you have comments, questions, or suggestions for show topics, and if you want more content like this don’t forget to subscribe. If you would like to reach out to Merrin, you can find her here: mmacrae@uwaterloo.ca Twitter: @merrinm Resources CEU Quiz: http://www.agronomy.org/education/classroom/classes/817  Intro to the Special Section from the Journal of Environmental Quality: Agricultural Water Quality in Cold Environments, “Agricultural Water Quality in Cold Climates: Processes, Drivers, Management Options, and Research Needs”: dx.doi.org/10.2134/jeq2019.05.0220 “Agricultural Water Quality in Cold Climates: Processes, Drivers, Management Options, and Research Needs”: dx.doi.org/10.2134/jeq2019.05.0220 Papers from Merrin’s Masters students James Cober and Tatianna Lozier: “Nutrient Release from Living and Terminated Cover Crops Under Variable Freeze–Thaw Cycles”: dx.doi.org/10.2134/agronj2017.08.0449  “Release of phosphorus from crop residue and cover crops over the non-growing season in a cool temperate region”:  https://www.sciencedirect.com/science/article/abs/pii/S0378377417301579 “Potential phosphorus mobilization from above-soil winter vegetation assessed from laboratory water extractions following freeze–thaw cycles”:  https://www.tandfonline.com/doi/abs/10.1080/07011784.2017.1331140 Other papers from this team: Agricultural Water Futures Project: https://uwaterloo.ca/agricultural-water-futures/ “Impacts of Cover Crops and Crop Residues on Phosphorus Losses in Cold Climates: A Review” review article from Jian Liu: dx.doi.org/10.2134/jeq2019.03.0119 Papers from Manitoba, Saskatchewan, and Environment Canada: “Evaluating the potential contribution of vegetation as a nutrient source in snowmelt runoff”:  https://www.nrcresearchpress.com/doi/full/10.4141/cjss2012-050#.Xd2KSehKhhF “Critical Factors Affecting Field-Scale Losses of Nitrogen and Phosphorus in Spring Snowmelt Runoff in the Canadian Prairies”: dx.doi.org/10.2134/jeq2012.0385 European and Nordic Papers: “Freezing–thawing effects on phosphorus leaching from catch crops”: https://link.springer.com/article/10.1007/s10705-014-9615-z “Freeze–Thaw Effects on Phosphorus Loss in Runoff from Manured and Catch-Cropped Soils”: dx.doi.org/10.2134/jeq2004.0415 Field, Lab, Earth is copyrighted to the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

“Winter Phosphorus Release from Cover Crops and Linkages with Runoff Chemistry” with Dr. Merrin Macrae Cover crops can offer a variety of ecosystem services, including reducing soil erosion. However, in colder climates, where cover crops can freeze and die over the winter, there is the possibility that the Phosphorus within cover crops can then leach into surface runoff. Dr. Merrin Macrae and her team decided to dive deep and discover whether or not this trade-off exists and, if so, to what extent. Listen to learn: <ul> <li>What do Nalgene bottles and ping pong balls have to do with research?</li> <li>What is it like to do field research in the winter?</li> <li>How can Twitter lead to working research relationships with farmers?</li> <li>Which factors contribute most to surface P runoff?</li> </ul> If you would like more information about this topic, this episode’s paper is available here: <a href="https://doi.org/10.2134/jeq2018.08.0307" rel="nofollow" target="_blank">https://doi.org/10.2134/jeq2018.08.0307</a> This paper is always freely available. If you would like to find transcripts for this episode or sign up for our newsletter, please visit our website: <a href="http://fieldlabearth.libsyn.com/" rel="nofollow" target="_blank">http://fieldlabearth.libsyn.com/</a> Contact us at <a href="mailto:podcast@sciencesocieties.org">podcast@sciencesocieties.org</a> or on Twitter @FieldLabEarth if you have comments, questions, or suggestions for show topics, and if you want more content like this don’t forget to subscribe. If you would like to reach out to Merrin, you can find her here: <a href="mailto:mmacrae@uwaterloo.ca">mmacrae@uwaterloo.ca</a> Twitter: @merrinm Resources CEU Quiz: <a href="http://www.agronomy.org/education/classroom/classes/817" rel="nofollow" target="_blank">http://www.agronomy.org/education/classroom/classes/817</a> Intro to the Special Section from the Journal of Environmental Quality: Agricultural Water Quality in Cold Environments, “Agricultural Water Quality in Cold Climates: Processes, Drivers, Management Options, and Research Needs”: <a href="http://dx.doi.org/10.2134/jeq2019.05.0220" rel="nofollow" target="_blank">dx.doi.org/10.2134/jeq2019.05.0220</a> “Agricultural Water Quality in Cold Climates: Processes, Drivers, Management Options, and Research Needs”: <a href="http://dx.doi.org/10.2134/jeq2019.05.0220" rel="nofollow" target="_blank">dx.doi.org/10.2134/jeq2019.05.0220</a> Papers from Merrin’s Masters students James Cober and Tatianna Lozier: “Nutrient Release from Living and Terminated Cover Crops Under Variable Freeze–Thaw Cycles”: <a href="http://dx.doi.org/10.2134/agronj2017.08.0449" rel="nofollow" target="_blank">dx.doi.org/10.2134/agronj2017.08.0449</a>  “Release of phosphorus from crop residue and cover crops over the non-growing season in a cool temperate region”: <a href="https://www.sciencedirect.com/science/article/abs/pii/S0378377417301579" rel="nofollow" target="_blank"> https://www.sciencedirect.com/science/article/abs/pii/S0378377417301579</a> “Potential phosphorus mobilization from above-soil winter vegetation assessed from laboratory water extractions following freeze–thaw cycles”: <a href="https://www.tandfonline.com/doi/abs/10.1080/07011784.2017.1331140" rel="nofollow" target="_blank"> https://www.tandfonline.com/doi/abs/10.1080/07011784.2017.1331140</a> Other papers from this team: Agricultural Water Futures Project: <a href="https://uwaterloo.ca/agricultural-water-futures/" rel="nofollow" target="_blank">https://uwaterloo.ca/agricultural-water-futures/</a> “Impacts of Cover Crops and Crop Residues on Phosphorus Losses in Cold Climates: A Review” review article from Jian Liu: <a href="http://dx.doi.org/10.2134/jeq2019.03.0119" rel="nofollow" target="_blank">dx.doi.org/10.2134/jeq2019.03.0119</a> Papers from Manitoba, Saskatchewan, and Environment Canada: “Evaluating the potential contribution of vegetation as a nutrient source in snowmelt runoff”: <a href="https://www.nrcresearchpress.com/doi/full/10.4141/cjss2012-050#.Xd2KSehKhhF" rel="nofollow" target="_blank"> https://www.nrcresearchpress.com/doi/full/10.4141/cjss2012-050#.Xd2KSehKhhF</a> “Critical Factors Affecting Field-Scale Losses of Nitrogen and Phosphorus in Spring Snowmelt Runoff in the Canadian Prairies”: <a href="http://dx.doi.org/10.2134/jeq2012.0385" rel="nofollow" target="_blank">dx.doi.org/10.2134/jeq2012.0385</a> European and Nordic Papers: “Freezing–thawing effects on phosphorus leaching from catch crops”: <a href="https://link.springer.com/article/10.1007/s10705-014-9615-z" rel="nofollow" target="_blank">https://link.springer.com/article/10.1007/s10705-014-9615-z</a> “Freeze–Thaw Effects on Phosphorus Loss in Runoff from Manured and Catch-Cropped Soils”: <a href="http://dx.doi.org/10.2134/jeq2004.0415" rel="nofollow" target="_blank">dx.doi.org/10.2134/jeq2004.0415</a> Field, Lab, Earth is copyrighted to the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

Winter Phosphorus Release in Cover Crops with Dr. Merrin Macrae