Managing Manure Nitrogen - Calculation Answers
Charles Shapiro
Author
07/06/2018
Added
54
Plays
Description
answers to calculation during nitrogen dynamics lesson
Searchable Transcript
Toggle between list and paragraph view.
- [00:00:00.336]Okay, your calculations, hopefully you're done.
- [00:00:04.020]You've had some help if you've needed it
- [00:00:07.310]and now we'll go through what the answers are.
- [00:00:10.540]So, what is the value
- [00:00:11.920]for that first year without incorporation?
- [00:00:15.340]We need to calculate both the ammonia and the organic.
- [00:00:17.940]We do that separately
- [00:00:19.510]and this is a very easy one
- [00:00:21.340]'cause you have to multiply it by zero.
- [00:00:23.330]If you don't incorporate, you lose all that ammonia,
- [00:00:26.080]it goes up in the air.
- [00:00:28.140]So, we really need to only be concerned
- [00:00:30.250]with the organic N
- [00:00:31.430]and here we had 16.4 pounds
- [00:00:34.480]and we had availability factor of .25,
- [00:00:38.060]so that works out to 82 pounds.
- [00:00:41.130]Since there's no ammonia N,
- [00:00:42.870]the total available this year is 82 pounds.
- [00:00:46.950]Now, if we incorporated immediately,
- [00:00:48.640]we have a different situation.
- [00:00:50.600]We have almost 100% of that is conserved, 95%,
- [00:00:55.290]so we get 91 more pounds
- [00:00:58.360]by incorporating right away.
- [00:01:00.790]The organic N is the same.
- [00:01:02.610]We get the same 82 pounds
- [00:01:04.650]regardless of whether it's incorporated or not.
- [00:01:07.970]So, if you add those together,
- [00:01:10.290]these two examples, there's 90 pounds difference
- [00:01:13.995]at 50 cents a pound of nitrogen,
- [00:01:16.720]that's a $45 per acre difference in value
- [00:01:19.960]of that manure.
- [00:01:21.000]So, if you can incorporate it,
- [00:01:23.277]it saves you some money.
- [00:01:25.270]Now, if you're in a highly erodible situation
- [00:01:27.500]and you can't do the tillage,
- [00:01:29.042]you have to take that into account.
- [00:01:33.660]So, what's the answer to the following year?
- [00:01:39.770]The first part of the question might be
- [00:01:41.840]if we don't incorporate it in the first year
- [00:01:44.430]and again, it doesn't really matter
- [00:01:46.540]in the second year, all the ammonia is gone,
- [00:01:49.150]so it doesn't matter whether we incorporate or not
- [00:01:51.220]in the first year
- [00:01:52.370]and so, we use that .15 figure
- [00:01:55.836]and we come up with 49 pounds available,
- [00:02:00.490]almost 50 pounds.
- [00:02:01.610]Again, if you don't take this into account,
- [00:02:04.040]at 50 cents a pound of nitrogen,
- [00:02:05.780]you're losing $25 an acre in lost nitrogen.
- [00:02:12.310]It's still there
- [00:02:13.150]but you're probably putting on fertilizer and nitrogen
- [00:02:15.890]that you didn't need.
- [00:02:17.520]If you incorporated it the first year,
- [00:02:20.670]you get the same exact answer
- [00:02:22.340]'cause again, ammonia N doesn't make any difference
- [00:02:26.470]going into the second year.
- [00:02:28.620]Now, before we finish this section,
- [00:02:31.180]we just want to make one little warning
- [00:02:34.500]or a couple of warnings about his.
- [00:02:37.240]When we do the calculations pre-season,
- [00:02:40.010]it's just an estimate, we're guessing.
- [00:02:42.720]We could be off in either direction.
- [00:02:45.200]We think that our availability factors are conservative.
- [00:02:49.910]In other words, we are saying that the availability is lower
- [00:02:54.510]than what it actually is, so if we say 25%,
- [00:02:57.710]it's probably 30 or 35%.
- [00:03:00.070]So, you don't have to build in anything for safety
- [00:03:03.200]because our figures already have that in.
- [00:03:05.460]It depends on the moisture and the temperature
- [00:03:08.020]during the season.
- [00:03:09.220]During hot, dry years,
- [00:03:10.950]you probably not gonna get as much
- [00:03:12.630]as during years where the temperatures are normal
- [00:03:15.760]and we get good rainfall once a week
- [00:03:18.790]or something like that.
- [00:03:20.640]The best way to handle this
- [00:03:22.580]is to do some kind of in-season testing
- [00:03:25.320]with a chloroform eater or a sensor
- [00:03:28.720]or some way to assess
- [00:03:31.350]if the crop needs more nitrogen or not.
The screen size you are trying to search captions on is too small!
You can always jump over to MediaHub and check it out there.
Log in to post comments
Embed
Copy the following code into your page
HTML
<div style="padding-top: 56.25%; overflow: hidden; position:relative; -webkit-box-flex: 1; flex-grow: 1;">
<iframe
style="bottom: 0; left: 0; position: absolute; right: 0; top: 0; border: 0; height: 100%; width: 100%;"
src="https://mediahub.unl.edu/media/9716?format=iframe&autoplay=0"
title="Video Player: Managing Manure Nitrogen - Calculation Answers"
allowfullscreen
></iframe>
</div>
Comments
0 Comments