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Irrigation Pumping in the Central Sands of Wisconsin, Nocco, WI


Hi, my name is Molly [Conoco], and I received a sare grant for my graduate research I’m working on a Phd at the University of Wisconsin-Madison and My degree program is through the [nelson] institute for environmental studies and the actual program is an environment and resources so I we are standing in the Wisconsin central sands and here’s my mouth of Wisconsin and it’s in the center of the state and it is a a region that is characterized by the Sandy soils in the sandy soils were caused by the Movement of the Glacier the Glaciers and like a catastrophic draining event of the Glacial Lake, Wisconsin and Because of that the soils they don’t hold a lot of water. They don’t hold a lot of nutrients And this is the prime region in Wisconsin where irrigated agriculture. [ohs] is taking place and This is a potato field towards the end of its life It’ll actually be killed in about a week from now. So you can see it’s already started to siness on its own and potatoes are one of the main irrigated crops in this region and What I’m currently doing is looking at how Irrigation at this scale because it is it is a large a relatively large scale in a concentrated region. It’s about fun It’s a it’s thousands of High-capacity Wells in this area and There have been in the past ten years or so some surface water stress of the the streams and the lakes in this region, and there’s a lot of you [know] high quality trout streams so basically there’s a conservation community Dilemma here people are upset and people are upset about water, so The positive part of that is people are interested in managing water So really I have I would say a few main goals of my phd one is to just try to understand and characterize the water budget from these irrigated agriculture That and what the Sarah grant has helped me to do is install This which it’s not it’s not super impressive because you cannot see what’s underground, but it’s a passive capillary wick life scimitar So you just have to believe me That right in this region About eight feet underground. There’s an instrument that measures drainage vertical drainage and that is a very challenging thing to measure and As you can imagine it was a very challenging thing to install and it has about a 10-inch diameter, and they’re 25 of them in different crop in six different cropping systems on this farm and So that is capturing drainage, and then we have several Meteorological stations that are capturing met variables, I don’t think you can’t see it any of the full met stations right now and we have Stratified soil moisture and temperature probes all the way up so basically we’re measuring everything we can including precipitation and irrigation to back into evapotranspiration Which is the main issue at hand is the hypothesis is irrigated agriculture is Increasing consumptive groundwater use because we are irrigating the plants until they don’t need any more water So they can transpire at the highest rates possible And it’s just a challenge to measure evapotranspiration. So that’s kind of step one and I’m basically trying to the lysimeters or one of three ways that I’m trying to characterize you back with transpiration and then the Drainage is considered potential groundwater recharge, so that’s the other part that I’m working on you can kind of see if you look across There are these white? These white sensors on a post do you kind of see the line of them? So this that’s like a it’s a temperature and relative humidity Transect across this field and it kind of gets at the second area that I’m focusing my work on which is what is the relationship between irrigated agriculture and regional climate We know from Data and studies out west where it is very arid that these? Concentrated regions of irrigated agriculture can actually shift climate patterns on through irrigated cooling So you can have warmer nights and cooler days in these regions, so we’re curious everyone’s always said It’s too humid for that to happen in the midwest, so we’re testing that hypothesis Both at the local scale so what this transect is measuring is when the actual center pivot goes over it? What is the temperature decline and the relative humidity rises so she ated with that and that’s one of those things that if we can? understand that effect we can build better models I also have a similar transect that is at a larger regional scale so every two kilometers through the the Fattest portion of the Central sands that’s irrigated [I] have one of these sensors to look at how this is Manifesting at you know that regional scale so like this is more of a mechanistic understanding and that’s just to see are you you know more of a Proof of concept Desta if we’re seeing this in the region, so that’s that’s the other part major part of my work. So really I’m trying to measure what I can measure and then Bill better models that that’s that’s really the next the next step so that’s what I’m working on And I thank you [all] for for your funding and I really appreciate it and hopefully I will have some very you know interesting results to report So there’s a reservoir that sits at about eight feet below the surface And that that collects the drainage water and because the soil is so sandy we make an assumption that all of the flow is vertical that’s a physicist maybe know that that is a huge assumption to make Because you know any soil scientists will tell you that there’s lateral flow that happens in the soil But but the soil in this case is so sandy that it’s fairly safe to make that assumption however the point at which We are collecting drainage it basically has this Fiberglass wick material that maintains like a constant soil water tension or potential that Keeps it so that that spot is equivalent to about field capacity for a sand So you’re collecting drainage at about field capacity so I’m going [to] pump out the drainage hopefully we’ve got some all right There it is you

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