PLSCS 2600 - 33 - Practical Soil Nutrient Management II

Estimated read time: 1:20

Summary

The lecture on Practical Soil Nutrient Management II, focused on various dynamics of nutrient management, fertilizers, and their environmental impact. The professor announced a change in the lecture schedule and content delivery, emphasizing the importance of understanding nutrient cycling and management techniques. Key concepts included nutrient availability, the role of soil tests and plant response in nutrient assessment, and how different factors like climate, texture, and mineralogy affect nutrient dynamics. The discussion also covered nutrient loss through erosion, leaching, and plant uptake, and the significance of healthy plant growth in optimizing nutrient use. Fertilizer sources, from natural to manufactured, and their role in soil fertility were also highlighted, with attention to energy costs associated with nitrogen fixation processes.

Highlights

No class next Wednesday morning due to Thanksgiving break, but changes in lecture content will be introduced after.🦃
Nutrient management entails considering factors like mineralogy, texture, climate, and more.🌍
High fertility soils can lose more nutrients during erosion due to higher nutrient content. 🌊
Healthy plants capture more nutrients, reducing losses through erosion and leaching. 🌿
Understanding soil and plant specifics is crucial for effective nutrient management and fertilizer application. 📊

Key Takeaways

Nutrient management involves understanding the cycling and loss of nutrients in soil ecosystems. 🌱
Healthy crops optimize nutrient use, reducing environmental losses.🌾
Both natural and manufactured fertilizers contribute to soil fertility but have different implications on sustainability and management. 💧
Soil testing and understanding plant response are vital in determining nutrient availability.🔍
Effective fertilizer management is about concentration and the movement of nutrient pools.🔄

Overview

In today’s lecture, the professor primarily dealt with the complex dynamic of soil nutrient management. The discussion began with administrative announcements, such as cancelling next week’s Wednesday class, and shifted towards explaining upcoming changes in lecture content presentation. This set the stage for a deep dive into nutrient cycling, nutrient management strategies, and their environmental impacts.

The professor covered significant topics like nutrient availability, emphasizing how soil characteristics such as mineralogy, texture, and climate impact these dynamics. Erosion, leaching, and plant uptake were discussed as primary pathways of nutrient loss, connecting to the critical role healthy crops play in nutrient management by efficiently using available nutrients and reducing environmental losses.

Further, the class explored the origin and role of different fertilizers, from natural organic sources to synthetically manufactured ones, highlighting the energy-intensive processes involved in nitrogen fixation. The emphasis was on appreciating the ways these fertilizer sources affect soil fertility and nutrient management strategies. Overall, the lecture was rich with information about managing nutrient dynamics in varied soil contexts.

Chapters

00:00 - 01:30: Introduction and Announcements The chapter introduces some initial announcements before the lecture. The first announcement is regarding a class schedule during the Thanksgiving break. Officially, vacation starts at noon on Wednesday, and the speaker confirms that they will not be teaching on Wednesday morning even though students are welcome to attend. They mention having conducted classes in the past with minimal attendance.
01:30 - 02:00: Changes to Lecture Schedule The chapter discusses changes to the lecture schedule. The instructor decides to repeat a lecture following a break, which is not typically allowed, but is deemed necessary. Significant changes to the upcoming lectures are planned, and students will be instructed on necessary preparations. The current calendar should not be strictly followed during this period.
02:00 - 06:00: Nutrient Management Overview The chapter titled 'Nutrient Management Overview' discusses an upcoming reorganization and modification of content related to nutrient management. The presenter plans to introduce changes in the material sequence and add new components to the content. The focus will remain on completing the current segment on nutrient management, fertilizers, and their impact on environmental dynamics and quality. The title suggests that future discussions will continue along these themes.
06:00 - 09:00: Nutrient Availability This chapter introduces the concept of nutrient availability, which will be explored from multiple perspectives throughout the semester. These perspectives include pollution, remediation, management, and measurement. The lecturer advises students not to strictly follow the calendar as the upcoming seven lectures will deviate from the planned schedule.
09:00 - 15:00: Soil Tests and Plant Responses This chapter discusses nutrient management in relation to soil tests and plant responses. It highlights the importance of considering nutrient cycling, management of nutrient loss and gain, mineralogy, parent material, and soil texture.
15:00 - 22:00: Nutrient Cycles and Losses The chapter 'Nutrient Cycles and Losses' delves into the intricate roles of texture and parent material in influencing soil's cation exchange capacity (CEC) and anion exchange capacity (AAC). Beyond the physical components, the text explores how climatic conditions impact nutrient processes predominantly governed by biological systems. It elaborates on how water availability and temperature are critical in determining the distribution and activity of organisms, while also emphasizing the interconnectedness of climate and water in these ecological processes.
22:00 - 39:00: Managing Nutrient Sources The chapter titled 'Managing Nutrient Sources' discusses the factors affecting nutrient movement in water systems. It highlights the role of temperature in chemical reactions, both with and without biological interaction. Biological factors, closely linked to climate, also play a crucial role in nutrient solubility and movement, with the type of organic matter present significantly influencing these processes. Additionally, the chapter touches on the importance of pH in determining the solubility of nutrients.
39:00 - 48:00: Questions and Closing Remarks The chapter discusses how solubility and pH levels affect nutrient exchange complexes, retention, and movement through a system. The focus is on defining and understanding nutrient availability, which is described as a vague term but crucial for the topic at hand.

PLSCS 2600 - 33 - Practical Soil Nutrient Management II Transcription

00:00 - 00:30 i got a couple pieces of news and then we're going to get going on the lecture um the first piece and i'll say this again on friday and on monday um just because um next wednesday uh vacation officially star vacation thanksgiving break officially starts at noon but i will not be teaching the that well i won't you guys can come but i'm not going to be here uh wednesday morning i used to do it in the past but there was like 10 people in the classroom and basically i just had to
00:30 - 01:00 teach the same lecture again on the monday after break so we don't do it anymore um it's not we're not supposed to do that but it's just it's not worth it um the second thing is that after this lecture um we still i'm going to be changing up the lectures significantly i'll give you guys a heads up on what thing to download if you're bringing in notes and things like that but don't follow the calendar uh directly
01:00 - 01:30 content-wise it's all going to be the same i'm going to be adding some stuff but i want to present it a little bit differently in a different sequence with different materials okay so just be aware that's coming down the pike okay all right so what i like to do is finish off this component of nutrient management nutrient management and fertilizers and this dynamic environmental dynamics and quality i think this actually might be a good title for what's going to happen for the
01:30 - 02:00 rest of the semester we're going to be talking about this in a lot of from a lot of different perspectives from some sort from pollution's perspective from a remediation perspective from a management perspective from a measurement perspective um so i think when i say don't follow the calendar as i as to the lecturers for the next i guess for seven lectures seven lectures left something like that don't follow it but this is basically
02:00 - 02:30 what the content's gonna be all right questions you're good to go all right so we're going to be talking about nutrient management and we've talked about nutrient management these are the things that you have to keep in mind when you're thinking about how nutrient cycling is working how you're going to be managing issues of nutrient loss nutrient gain you're going to have to be thinking about the mineralogy the parent material okay you're also in relationship to that parent material you're going to have to be thinking about texture
02:30 - 03:00 now texture obviously has this issue with surface area when we start talking about texture and parent material together we're starting to talk about cec and aac so exchange complexes okay we also have to think about the climate the climate is going to control specifically for nutrient processes that are controlled by biological systems certainly is going to control water the amount of water and the temperature is going to control the distribution and activity of organisms but water and climate also have to do
03:00 - 03:30 with our temperature water and temperature also have to do with the sort of the chemical reactions with or without biological mediation okay biology obviously related to climate but the type of organic matter in the biota and what's going on there is certainly also going to affect how these nutrients are moving through the system ph solubility of nutrients
03:30 - 04:00 the solubility of these elements is really dependent upon the ph and then in turn this ph has a huge effect on exchange complexes so the retention of those nutrients and how those nutrients move through the system and then finally the nutrients themselves okay so today we're going to talk about availability nutrient availability okay what is it it's a it is a vague term okay what is
04:00 - 04:30 it though okay well when we talk about nutrient availability we sort of talk about three things but most people think well how much of it is going to get to the plant okay well how much of it's going to get to a plant has a lot to do on what is the concentration of that nutrient in the solution right it makes sense okay then once that nutrients gone what's the speed of replenishment of that nutrient back into that nutrient solution and then finally
04:30 - 05:00 when it's in the solution how fast is it going to be moving through that system okay last lecture we talked about the issue of mass flow versus sort of concentration gradients okay that has a huge impact on this mobility and the mobility of the or the solubility of those nutrients or those ions in turn have a huge effect on the mobility sort of they're playing back to each other
05:00 - 05:30 okay the definition is the ability of a soil to maintain high concentrations it's not really the ability to maintain high concentrations but a fertile soil in a in essence is its ability to hide maintain high concentrations in solution and in the vicinity of the root if the nutrients are in high concentration and they're not near the roots they're not going to do a lot of good for the plant right okay now
05:30 - 06:00 another definition we should talk about is this definition of what fertilizer is generally people when you say fertilizer most people think of it's an inorganic material that you buy at agway or something like that okay a fertilizer is a material natural natural or synthetic inorganic organic that provides a useful notice that it's underlying useful quantities of plant nutrient in a form that become can become soluble in the soil and it and in fact can it it can be
06:00 - 06:30 soluble already or can become soluble okay it's dependent upon errors its invaluability is basically dependent on three factors and those factors are the ones we talked about already these factors okay and the fertilizer in essence also builds up the reserves to provide useful quantities okay the definition is really this component
06:30 - 07:00 of it now that availability can vary from time to time and from soil to soil from condition to condition okay availability may vary from soul to soil even when that same amount of nutrient is present in each one of those soils now why well it depends on those three factors again the concentration of those nutrients in
07:00 - 07:30 the solution the speed of the nutrient replacement and finally the mobility of that nutrient in the soil sorry i skipped back i know you guys hate it when i do that okay keep those three things in mind some of the nutrients can be replenished by organic decomposition if i have organic matter in my soil that's going to replenish the availability of those nutrients okay
07:30 - 08:00 it's going to depend on the kind of organic matter it's going to depend on the soil water content and temperature climate again nutrients some nutrients can be retained more tightly in the soil because of higher capacities of that soil to hold onto certain things the classic example here is the phosphorus one what happens when the systems go the ph of the system goes low
08:00 - 08:30 how does the phosphorus bind in those systems aluminum and iron okay as the systems become at a higher ph phosphorus are bound to calcium maximum availability of phosphorus tends to be around 6.5 because you're minimizing calcium and aluminum and iron okay so that's a property of retention that's a property of the soul that has re that's a retention property of the
08:30 - 09:00 soil that holds on to that in this case phosphorus does that make sense to everybody yeah ish kind of so how do we in fact figure out what availability is and there's basically two methods one is a soil test okay and there's three factors that control this availability and then a plant response
09:00 - 09:30 so let's start with the soil tests what are the factors that can control that soil test now if i'm doing a soil test and i take a soil and i measure the nutrient availability and there's a lot of different types of tests that we use okay most of the tests that we use basically are mimicking the ability of a plant to extract nutrients it's not taking it's not a test and we talked about this in la and lab okay it's not a test that's going to
09:30 - 10:00 take a soil and basically completely digest it and tell me exactly what everything is in the soil what it's going to do is it's going to be a test that can extract or mimic the ability of a plant to extract this is not a total disillusionment of the soil okay this is basically a wash of the soil it's washing at a concentration that basically the plants would be able to wash it off does that make sense okay so we need to have an understanding of what the concentration of the nutrients are
10:00 - 10:30 in the solution not in the total volume okay we need to have an understanding if this this test if it's going to be effective needs to have an understanding about the speed of the replacement of that concentration in the soil okay now it may in fact not be the test but it may be interpretations based on the test now when we did the submissions for dillman hill part of that submission test was
10:30 - 11:00 we want to know what these nutrients are and we this is the type of plant that we have but we also gave a lot of information about the soil type and its location well why did we do that a lot of that had to do with this i wanted to know what type of soil it is so that i have some sort of idea about i so so i have some sort of idea about cec and the ability of that system to
11:00 - 11:30 exchange these nutrients on exchange complexes right if i just give you a measurement of this i'm not going to have any idea about the measurement of replacement and then finally depending upon what kind of nutrient it is and in what kind of soil it is i have an understanding of the mobility of that nutrient in that particular soil does that make sense to everybody questions
11:30 - 12:00 should i restate that yes okay so let's think about this if i need to have a test that tells me about nutrient availability for my plants or for whatever i need to have a test that will mimic the plant's ability to extract that material does that make sense okay and that's why i want to have sort of the concentration of the nutrients that are in the soil solution but i also
12:00 - 12:30 want to have an understanding about the speed of replacement okay because if the plants can only extract a little bit there's not going to be a lot of replacement on the other hand if the plant's going to extract a lot there's going to be a lot of replacement because of the cation exchange capacity does that make sense also potentially weathering reactions does that make sense now for me to be able to give you that type of information i can't strictly depend upon a test alone
12:30 - 13:00 i need to have some sort of understanding about what kind of plants you're growing because i need to know what their lifestyle is but also their ability to extract stuff but i also need to know stuff about the soil that they're growing in okay if i just have the liquid of the soil that they're growing in it doesn't tell me anything about the surface areas of the soil that they're growing in the solid part right that's why we ask questions about the soil
13:00 - 13:30 does that make sense cool all right the second way we can basically figure out what's going on or a sort of an assessment of nutrient availability is basically the plant response okay i can put a plant in the soil okay i can give it various amount of nutrients and i can look at its response to that soil and the amount of nutrients that i add these are field trials we do this all
13:30 - 14:00 the time and this is we and this is basically the basis for many of our interpretations of these soil tests what we do is we go out in the field we plant these things we give it a variety of different nutrients in a variety of different soils we see what this response is so that when we get your soils from or anybody's soils we have a number of what where that nutrient is in the system i.e how much has been added to the system and we have a measurement of what kind
14:00 - 14:30 of soil it is and we know what kind of plant is growing so we just basically correlate the soil test with the response curve and we can give you an idea about how much you have to add to get to this point does that make sense yes is it i'm definitely going to start a coffee business in here all right and again it's based on these three
14:30 - 15:00 characteristics of availability sure number two i mean how understanding the context in which the soils are in how would you express that in terms of are you would you would that be reflective quantity of nutrients or all right so the question let me restate the question the question is um in in reference to
15:00 - 15:30 how would we how would we communicate this issue of speed for replenishment what does that actually mean how fast something is is that in essence you're asking yeah so if if the plant starts sucking nutrients out of the soil solution how fast is that response it's a good thing i can return the answer because i'm i feel like i'm really good cornell student i can i can
15:30 - 16:00 spit back the question for you but i don't necessarily know the answer on that one because it's going to be really dependent upon the different types of nutrients some of them are going to be very quick potassium bang okay but on the other hand potassium can also bind fairly well with things um calcium is going to be something that's really not calcium phosphorus is going to be something that's really slow and i think the speed has less to do with the actual time and more to do with the plant
16:00 - 16:30 if a plant so if you think about the replenishment certain plants certain plants all plants they have certain stages of their life that they need to have certain nutrients now in general they have that we all have sort of base requirements but when they go into fluorescence or they seed set or something like that during those periods of time they have some sort of like peak need for certain nutrients and that's really more about what we're trying to it's not like base numbers
16:30 - 17:00 that we're trying to give them we're trying to give them the amount of nutrients they need at their stage of life so it's more a timing thing so right so classic fertilized fertilizer inorganic fertilizer amendments it's you don't put all the fertilizer at the beginning of the season you go in there at certain times of the year and you side dress okay and you give the fertilizer when the plant needs it and this is a this is a really good example of when you really
17:00 - 17:30 want to do sort of this is sort of middle of the road type of fertilizer but you really want to have some base level fertilizer in the soil and this is classic organic sources you know if i put organic material in there because organic matter decomposes slowly i'm going to always have this baseline of nutrient availability and then i got a certain crop in there that goes at one point it really needs a high demand well my organic fertilizer is not going to hack it because it's just not releasing
17:30 - 18:00 amount the amount of nutrients that that plant needs at that particular time and the argument there is that well then we go in there with some sort of quick release fertilizer now that's an argument that you know that there's a lot of room to argue about whether that's the way or not but the reality is plants need to have some sort of base level but then they also have to have these peak peak points in their plant in their lifestyle and their nutrient demands okay and that's where you sort of think about what this is
18:00 - 18:30 there is not any hard and fast rule that says nitrogen is going to be off with this potassium is going to be at this calcium is going to get this it really has to do with the type of soils that you're that you have in the system and what's actually in the concentration of the soil solution because it's exchanged between these two okay does that make sense to everybody all right so let's take the next step if we're thinking about this availability we need to start thinking about how the nutrients are getting into the
18:30 - 19:00 system and how they're being lost from the system okay and this is where we get back to nutrient cycles and their losses okay nutrient cycles and soils tend to be leaky especially in highly fertile soils now think about that term for a second we'll talk we'll come back to that why are they especially leaky in highly fertile soils okay nutrient losses basically depend on four things one is soil erosion if i'm taking the soil away i'm going to be taking the nutrients away certainly if i have crops that are taking nutrients up
19:00 - 19:30 when i harvest that crop and take it someplace else the nutrients are going to be going with it i also have volatilization of gases and leaching these two you guys are fairly familiar with okay now let's go back to this idea about uh highly fertile soils tend to be more leaky okay it's not that they are inherently losing more stuff because they're highly fertile it has to do with the fact that if you think about where the pools of nutrients are okay if the pool of nutrient is in the
19:30 - 20:00 soil and the soil has a lot of fertility in it versus a soil that doesn't have a lot of fertility given the same amount of erosion from each one of those soils which one's going to be losing more nutrients the one that has more fertility right if i lose a pound of soil from an acre of a highly so highly fertile soil versus a poorly poor a low fertility soil i take a pound of soil off of each one
20:00 - 20:30 of them there's going to be more nutrients in the high fertility soil and the low fertility soil therefore it is more leaky okay the percentage of the entire system may not be any different i may be losing 10 percent in both cases but the absolute amount is going to be different does that make sense i'm not even seam yes yeah okay all right so let's talk a little bit
20:30 - 21:00 about each one of those erosion basically removes the phosphorus and the nitrogen in the solids materials okay but we're also going to see more erosion when we have enhanced it's going to be enhanced when we have bare soil okay if i don't have something that's holding the soil in place i'm going to have more erosion okay if i'm more erosion i'm going to have more nutrient loss okay because of the nutrients where where this solid material is going it's basically going down into streams and into lakes this basically causes eutrophication downstream so i see i see
21:00 - 21:30 algal growth farther down in the system or in lakes in essence okay crop removal this is necessary if we're cropping something we're going to have to harvest okay and if we harvest we're basically taking with us the n and k are basically removed the most from this system um but we can minimize some of this loss by returning crop residues to the soil if we're just taking the seed and leaving the rest behind that rest the biomass of
21:30 - 22:00 the rest is going to have npk in it as well and that's going to go back into the soil as that material decomposes okay gaseous losses has to do with the nitrogen cycle predominantly okay but it can also have to do with sulfur okay basically when you're looking at the ammonification once that amine group from the crop residue or the organic matter decomposes and put into an ammonia ammonia is a gas so it can literally volatilize from the system okay certainly when you burn stuff you're gonna have volatilization as well
22:00 - 22:30 okay and also potentially when i start go the system starts going anaerobic okay if i start having something like denitrification okay i'm taking it from nitrate and putting into n2 the nitrate is an available form yes it can be leached but as it is converted into n2 gas it becomes volatile which means it can be lost from the system make sense okay leeching is the next one basically this is loss this is possible loss for
22:30 - 23:00 all soluble nutrients if it is soluble it will move from the water if the water is moving out of the soil system where the crop is growing it's going to be taking those nutrients with them makes sense okay it's most significant when we're talking about things like nitrogen sulfate and potassium phosphorus can also be lost but again you have to think about this phosphorus it binds very tightly depending upon the ph with aluminum and iron at the low phs calcium at the high phs and actually organic
23:00 - 23:30 matter in the mid-ranges okay we can minimize this loss actually we can minimize most of these losses by doing the right thing management wise but when we're talking about leaching we can minimize this loss by fertilizing at the right time and in the right amount why am i going to put excess nitrogen on the system when most of that's going to be leached away now the reason i'm putting nitrogen on the system is for my plants so i want to put it in a form that the plants can
23:30 - 24:00 optimize getting and minimize its loss okay classic example there would be that slide that i showed you about rice okay putting in the different types of nitrogen ammonium versus nitrate into different parts of the system to minimize its loss from the system right keeping the nitrate in the aerobic zone keeping the ammonia in the anaerobic zone yes they're going to migrate but it gives it one more step of the nitrogen cycle and the ability of one
24:00 - 24:30 more or slows down its loss and maximizes the plant's ability to capture before it's lost does that make sense is that you guys remember that slide yeah okay this is all premised on one hypothesis well maybe not premise but one hypothesis sort of holds a lot of these things together and this hypotheses that healthy crops use nutrients better now let's think about this why do we think i mean if we're trying to
24:30 - 25:00 if we're trying to minimize lots from the system we want to really maximize one of the things that we want to do is maximize the nutrient uptake into the plants right because the more the plants are taking up the less is leaving the system now granted we're going to harvest but potentially we're putting the residue back okay so why would healthy crops healthy plants use those nutrients better or prevent or
25:00 - 25:30 reduce the amount of loss from the system with the exception of the harvest think about it why would plants that are healthy versus unhealthy plants go well exactly so if they're healthy they're going to be producing more biomass and if are producing more biomass they are going to be harvesting more
25:30 - 26:00 nutrients they're harvesting more nutrients there's less of it to be lost through volatilization and leaching more biomass is also going to anchor more of the soil so i'm going to lose less of my soil through erosion i'm going to capture most of it in biomass which means some of it's going to be lost through crop harvesting but if i put that residue back in the system i'm basically putting it into that organic matter pool it's going to go
26:00 - 26:30 right back into the soil does that make sense questions a close i understand the question of the closed system i wouldn't actually call potted plants a closed system but yeah i understand the question there so if we're having a sort of a greenhouse operation or potted plant system how would we reduce
26:30 - 27:00 some of this well certainly a potted plant system you'd have a lot less erosion because you have a capture field okay but potentially material can be going out the bottom of the hole now that bottom of the hole is where you're going to see a lot of the leaching now how would you minimize that well you could have better control of how much water is going into the system or what more importantly the nutrients that are in that okay now those nutrients can be coming in as soluble fertilizer but those nutrients can also be being solubilized in that soil media and being
27:00 - 27:30 lost from the system so a lot of control is right there how you're delivering that water and in what amount i'm sure most of you guys if we think about these from pots since how in the house pots people that are growing house plants and things like that versus greenhouse plants in many greenhouse systems you're basically we just sort of excess water and let them come out the bottom because we have sort of the the you know the saucer is really the base of the of the greenhouse the pad okay but
27:30 - 28:00 often you see in with people that have house plants we see the salts actually build up in those pots over time that's when you start seeing the white coatings everywhere that's the salts building up the reason that that we're not seeing the leeching that system is we are actually seeing leaching what's happening is the water is going down and sitting in the pot and then as the plant respires it's bringing that water back up into the system so in essence we're creating it's not truly an arid system but we're
28:00 - 28:30 looking at evapotranspiration bringing that water back up now the transpiration isn't going to get rid of the salts and so in that scenario we're actually seeing a buildup okay it's not truly a closed system but really a lot of that has to do with how we're adding the water and what's in that water and how that water's interacting with the soil media does that make sense okay any other questions about that we feel good about this one no yeah okay
28:30 - 29:00 so this actually sort of segues right back into that pop the pot experiment but um managing these plant nutrients you sort of have to think about well where are we getting these nutrients okay certainly we can get them from organic sources but we also can get them from inorganic sources and we can get them from manufacture sources versus natural sources okay fertilizer manufacture and use does not necess doesn't does not create nutrients okay they're basically harvesting and
29:00 - 29:30 concentrating okay now when you say manufacturing here most of us think of sort of the petrochemical industry but you can certainly imagine this from sort of our organic waste management system as well vermicompost is a really good example of this composting in general is a really good example of this when we went out to the waste facility waste compost waste facility you guys remember the size of those windrows when the stuff came in they were rather large you know within six months they were rather small well what's going on
29:30 - 30:00 we're blowing all off a lot a lot of co2 is being blown off in essence we're concentrating material now granted there's ammonia and there's other things that are being blown off as well but in general we're looking at a concentration okay we then take that concentrated material and then put it back on our fields the same thing is happening with the petrochemical system you know the industry you know we're looking at basically taking some material and concentrating it and then transferring it and putting it on our
30:00 - 30:30 fields okay animal manure green manure compost they contain nutrients that are taken from the soil inorganic fertilizer are basically mining in rich deposits it's all about concentration of those nutrients okay therefore fertilizer in essence is a non-renewable resource in a sense because we're in all cases we're basically mining now there is one exception but in a sense this is also a non-renewable resource and that has to do with nitrogen with nitrogen fixation basically we're going
30:30 - 31:00 to be taking nitrogen from gas and using biological chemical fixation we basically take that nitrogen and convert it into ammonium or ammonia or n2 nh2 some variant of that okay but in all of those cases there is a large energy cost whether it's heat or whether it's atp question green manure is basically a cover crop or something like that that
31:00 - 31:30 i'm cutting and throwing into the system it's not literally green manure yeah okay okay questions no okay so let's talk a little bit about where these nutrients come from okay the first one is nitrogen and we always start not always generally we start with nitrogen because it's usually the one that's most extensively needed or used it's usually the smallest slat in the barrel
31:30 - 32:00 okay um it's also the one besides carbon hydrogen water that is used in most abundance okay nitrogen deficiency nitrogen deficiency is normal okay it's common and it's normal and plants are used to this okay few soils few soils can sustain multiple harvesting without some sort of nitrogen amendment the crops are just sucking it up too much and taking too much of it out okay phosphorus deficiencies are pretty
32:00 - 32:30 common there as well in fact uh i'm not sure if this this is correct at this point but 70 percent about 70 of agricultural soils not in new york state but about 70 percent of agricultural soils are deficit and phosphorus for plant uptake for some period of time okay questions on that one i thought i saw a hand no potassium sulfur zinc deficiencies are common but they are probably even with these deficiencies they're probably not the limiting nutrient usually it has to
32:30 - 33:00 it's usually nitrogen and in some cases phosphorus okay well i thought i didn't know the slide here oh i do i skipped a sorry i put the slide in the wrong spot other nutrients ironborn molybdenum manganese copper manganese magnesium and manganese deficiencies are less common but they are out there okay chlorine cobalt and sodium these are really
33:00 - 33:30 rare deficiencies but they do happen as well and then calcium its deficiency is rare but calcium is kind of interesting uh when calcium is in excess calcium can actually suppress other problems obviously acidity i mean you start throwing calcium in the system you're going to be raising the city it's basically a limiting reaction but you're also can potentially be dealing with reducing issues of sodicity and salinity this is where my slide was supposed to
33:30 - 34:00 be uh we're skip over the transition here was basically okay well we know what these nutrients are how do we in fact make decisions about fertility okay well let's take a look at our a number of different crops okay and this is a wheat an alfalfa and a tomatoes sort of a a variety of different crops here the take home story in a sense is from a farmer's perspective is how much yield are they going to be taking off that farm now this is probably a low yield for grain at this time but just imagine
34:00 - 34:30 that these are the numbers okay now from a fertility management sense what do these numbers actually mean well when i harvest this 6 tons or this 20 tons or this 20 tons i'm going to be taking nutrients with me okay now if i'm taking a wheat i got 6 tons i'm basically taking kilograms per hectare 120 kilograms of nitrogen 30 and phosphorous 30 potassium 25 calcium 15 magnesium and 5 sulfur so in essence
34:30 - 35:00 this is removal this is loss of nutrients for my system so you have to think about what you're growing to give you an idea about the yield and that yield what does that yield actually reflect okay now from a farmer's perspective think about the application rates now these are not the exact same and they're sort of out of order here okay so field crop we can think of as a wheat grain vegetables we can think of as tomato and alfalfa is
35:00 - 35:30 alfalfa okay this is the yield this is what's i'm losing now from a farmer's perspective i need to make that up somehow a grower's perspective well depending upon my crops this is what i'm going to apply again kilograms per hectare field crops about 100 kilograms of nitrogen seven phosphorus for potassium
35:30 - 36:00 that seems to be less why some of the residues staying but these numbers reflect what's leaving it's not the entire it's it's not just the it's not the entire plan it's just what's leaving the the rate that field need to propagands you have to add some to supplement
36:00 - 36:30 what's coming in in many cases that's going to be the answer so the answer was you know those nutrients are still in the soil but they're not necessarily at the rates that are available are they're not necessarily at the rates the plants need is that basically what you said okay and part of that is correct but part of that also has to do will what other type of organisms are in this system and how is this material getting into the system okay if there's organic matter in the system
36:30 - 37:00 there's still stuff there if there's minerals in the system there's still nutrients there there's still stuff there okay but i need to be able to re supply the nutrients based on the lifestyle of my plant okay and a good example of that one is actually looking at alfalfa if we look at alfalfa nitrogen and application rates alfalfa leaving the system look how much nitrogen is leaving the system yet me as a farmer
37:00 - 37:30 am i applying any nitrogen to my alfalfa crop now that has to do with my crop what is my crop it's alfalfa what has alfalfa the ability to do or not necessarily alfalfa but something that's in a symbiotic relationship with alfalfa nitrogen fixation put alpha into the system i don't have to add any more nitrogen if there's no nitrogen there it's not a big deal because they can do nitrogen
37:30 - 38:00 fixation alfalfa will go into my plant and i don't have to worry about it does that make sense so thinking about what your crop is what you're harvesting and what's leaving the system basically is telling the farmers what i need to put in the system based upon what crop i'm using makes sense yeah okay so let's go back to these fertilizers again okay where do these fertilizers come from
38:00 - 38:30 okay there's natural sources as well as mag as metals manufactured sources natural sources can be both organic as well as inorganic organic sources are often what we think of as biomass type of amendments manures mulches composts that type of thing but we can also have inorganic sources that are also natural example here is rock phosphate it's not like we're man we're manufacturing rock phosphate this is a geological material okay now we mine it and we can process
38:30 - 39:00 it to make it more concentrated as we talked about before but it's still a natural source it is inorganic though okay we also have what's going on here um we also can have manufactured materials and nitrogen is the classic one exit of this case and in soils plants animals ultimately comes from the atmosphere so when we're manufacturing it we're basically taking it from the atmosphere and this is the harbor process okay this harbor process for a manufacture sense
39:00 - 39:30 we're basically taking n2 gas with hydrogen we putting it over a catalyst under heat and we basically make ammonia okay the the heat and energy here basically comes from coal petroleum any kind of hydrocarbon type of thing anything to get energy okay we can then take this and under pressure with low temperature basically make ammonia okay and we can take this or say liquid anhydrous ammonia so we basically take this ammonia and concentrate it that's what we're making we this is making the ammonia this is
39:30 - 40:00 concentrating it okay worldwide nitrogen fixation about 50 of its biological about 50 of it is industrial other nitrogen fertilizers if we take that ammonia throw it under oxygen we can basically make nitrate turn it liquid okay a lot easier to transport than a gas okay if we wanted to concentrate it we can put it with ammonia we can put it with lime we can put it with calcium
40:00 - 40:30 make a urea we can actually put it with phosphate make an ammonium phosphate all different kinds of things the truth is all of these are basically easier to handle all right all of those are i don't what just that just happened did i totally miss something while you guys look at the screen and i was talking all right whatever uh luckily we only have five elections left um all of these basically can get concentrated and they're all generally easier to handle than ammonium okay
40:30 - 41:00 ammonius gas i.e that's the big issue there all right question so they actually make ammonia or they actually make you react from ammonia they just don't use they don't use the urine yeah they because it's easier it it from it i hesitate to say this i i can tell you the party line it's easier to handle and easier to to
41:00 - 41:30 deal with if you manufacture it rather than harvesting it from all these cows across the world or whatever sources i'm not necessarily sure i buy that argument but i do buy the argument the way the system is set up right now because of logistics and supply lines and things like that i do understand that argument but i mean we can get urea from natural sources um but right now the system's set up now we can all i can complain in fact i
41:30 - 42:00 i think this is wrong but that's the way the system's set up right now okay all right i'm not sure this is going to work right now so what i'd like to do is i was going to do this tomorrow or not on friday but maybe we'll do it right now we've got five minutes i'm not sure if i'm gonna be able to break these guys up into groups but i want you guys we've been talking about fertilizer
42:00 - 42:30 use your fertilizer and okay this are the three terms that i want to connect now there is no way we're gonna be able to do this in five minutes this is a lot of stuff okay there are a lot of connections here okay but what i'd like us to do for the next five minutes and i want you guys each to do this by yourselves we're not
42:30 - 43:00 going to break you guys up to the groom it's going to waste too much time think about it by yourselves pick one of these connections nutrients to fertilizer fertilizer to management management to nutrients pick one of them and i want you to come up with a list of the connections a list not an explanation a list because what we're going to do on friday at the tail end of this lecture that maybe we'll get or not at the tail end of it what we're
43:00 - 43:30 going to do is we're going to throw these three terms up again and we're going to put them on each one of these boards i'm going to come up with the complete list and then i'm going to break you guys up into groups and rather than five minutes i'm going to give you guys about 10 15 minutes you guys are going to be telling me a story okay so let's start right now let's make this list it will make friday a lot easier you're not turning this in okay you guys are not giving it to me you are hanging on to it and you're bringing it back on friday okay so pick
43:30 - 44:00 one of these pairs just one don't do all of them just pick one of these pairs make the connections go you got three minutes okay we got a list okay i want you guys to bring that in on friday okay i have two more slides that i want to hit before i let you guys go free um this was where we were the last sentence i basically said was because of this transformation from that ammonium we're basically making these
44:00 - 44:30 things much more easier to handle a liquid is a lot easier to handle than a gas okay and also it affects and in a sense it's not just sort of transportation but it also has a lot to do with how you actually apply it you have to have specialized equipment and we'll talk about this later i think friday tomorrow on friday you also have to have specialized equipment to to get gas in your soil it's not like you just spread gas and when i talk about gas i'm not talking like gasoline i'm talking like gas okay you can't just
44:30 - 45:00 sort of spread gas on your soil because it will just volatilize off okay so you actually have to have very specialized equipment to be able to use gaseous forms okay uh phosphorus fertilizer the main industrial source is rock phosphate which is basically appetite it's mostly like florida and things like that where we're literally mining rock okay they then process this to grinding which is what we basically see as a rock phosphate we don't get the rock itself they grind it up but we also can mix it with sulfuric acid make it
45:00 - 45:30 making super phosphate or we can put phosphoric acid in and basically turn it into triple super phosphate i can never barely say that but basically what you're looking at here is sort of a three percent phosphorus content this one says nine percent and this one you're looking at like 20 phosphorus content in that material okay so that would be an npk of uh potassium fertilizers these are another primarily a mined material we're
45:30 - 46:00 looking at sedimentary deposits sulfur we're basically looking at gypsum which is a mine material this is fairly abundant this is also mined from sedimentary material the other good thing about this is it's you're getting multiple nutrients on this one and it's fairly soluble okay elemental sulfur is another source this is fairly insoluble it's it's an oxide but in soil when you put it into with oxygen it basically turns into a sulfate now the problem with this is
46:00 - 46:30 that you potentially will get the hydrogen with it this is a lot of what you see with not the elemental sulfur but with the sulfides this is a lot of what you see with acid mine spoils as well as dredge material the sulfur comes up as a reduced sulfur gets in the presence of oxygen it becomes oxidized and basically turns into sulfuric acid okay that sulfuric acid will drop the ph of your soils pretty precipitously now this can actually be a management goal though if you have a really high ph soil you might in fact want
46:30 - 47:00 to use this sulfur not necessarily for the sulfur but for the protons to drop the ph of your soils to a more ideal zone for nutrient availability does that make sense yes kind of all right um then phosphorus we also have organic fertilizers this is the last slide before i'm going to set you guys free organic fertilizers basically are derived from plants ultimately they're derived from plants even if you're looking at a bone meal or a blood meal or something like that
47:00 - 47:30 because those animals are basically surviving off of plant life okay so unprocessed obviously things like leaves clippings things like that we also have animal process stuff where they're taking the plant material and we're looking at things like manure brown bone meal seaweed sludge all that kind of stuff and then we also have microbial process stuff where we're looking at composts okay vermicompost is sort of a blend between the two okay the vermicompost is an animal but
47:30 - 48:00 there's a microbial linkage there okay does this make sense okay the take home message from this slide and the some of the previous slides is fertilizer management and fertilizer manufacturing is really all about concentration and moving those different pools to where you want