Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil...
-
Upload
rudolf-rice -
Category
Documents
-
view
214 -
download
0
Transcript of Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil...
![Page 1: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/1.jpg)
NitrogenNitrogen
![Page 2: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/2.jpg)
The most limiting essential element in the environment
Nitrogen and Soil Nitrogen and Soil
Surface soil range: 0.02 to 0.5%
0.15% is representative
1 hectare = 3.3 Mg
Atmosphere = 300,000 Mg as N2
![Page 3: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/3.jpg)
Biological/Plant NitrogenBiological/Plant Nitrogen
Amino acidsProteinsEnzymesNucleic acids (DNA)Chlorophyll
Component of living systems
Strongly limiting in the Environment
![Page 4: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/4.jpg)
DeficiencyDeficiency
Chlorosis – pale, yellow-green appearance primarily in older tissues.
![Page 5: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/5.jpg)
ExcessExcess
Enhanced vegetative growth – lodgingOver production of foliage high in N Delayed maturityDegraded fruit quality
![Page 6: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/6.jpg)
Distribution/CyclingDistribution/Cycling
Atmosphere Soil / soil O.M. Plants, animals
N2, NO, N2O
NH4+, NO3
-, R – NH2
Proteins, amino acids
Organic Nitrogen (plant tissue, Soil Organic Matter): R – NH2
During organic decomposition, R – NH2 is usually broken down to NH4+
NH4+ is converted to NO3
- by soil microorganisms
![Page 7: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/7.jpg)
Mineralization: Decomposition of organic forms releasing nitrogen into the soil, generally as NH4
+
Immobilization: Plant uptake of mineral nitrogen, removing it from the soil and incorporating into plant
tissue.
Forms: mineral and organic
Organic: plant/tissue N R-NH2
Mineral: soil N NH4+, NO3
-
Cycling in the Environment
![Page 8: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/8.jpg)
AmmoniumAmmonium
NH4+R – NH2
organic mineral
Mineralization
Immobilization
NH4+ or NO3
- R – NH2
![Page 9: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/9.jpg)
Organic and Mineral NitrogenOrganic and Mineral Nitrogen
Organic R – NH2
Mineral NH4+ , NO3
-
mineralization immobilization}
Available toplants
1-2% generally available
NH4+
![Page 10: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/10.jpg)
Nitrogen in the SoilNitrogen in the Soil
Leaching
Adsorption/Fixation Nitrification
Plant uptake
NH4+
Volatilization
NO3-
![Page 11: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/11.jpg)
Adsorption and FixationAdsorption and Fixation
NH4+
ExchangeClay Colloid
OrOrganic matter
NH4+
NH4+
NH4+
NH4+Fixation
![Page 12: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/12.jpg)
NitrificationNitrification
NH4+ NO3
-NO2-Nitrosomonas nitrobacter
Aerobic (oxygen)
Anaerobic (low oxygen)
![Page 13: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/13.jpg)
NitrateNitrate
NO3-
NH4+ NO3
-NO2-Nitrosomonas nitrobacter
Loss of productivityEnvironmental hazard
Leaching to groundwater, surface water
(to plants)
![Page 14: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/14.jpg)
Environmental ImpactEnvironmental Impact
Methemoglobinemia – reduction by bacteria in ruminants and infants
NO2-NO3
-
Eutrophication – stimulation of algal growth, depletion of oxygen
![Page 15: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/15.jpg)
EutrophicationNitrogen
Photosynthetic life
bacteria
O2
![Page 16: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/16.jpg)
N-impacted
Unimpacted
![Page 17: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/17.jpg)
Control Control
Split applicationsNitrification inhibitors
Slow release fertilizersCover crops
Encourage natural N fixation
NH4+ NO3
-NO2-Nitrosomonas nitrobacter
![Page 18: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/18.jpg)
The most limiting essential element in the environment
Nitrogen and Soil Nitrogen and Soil
Surface soil range: 0.02 to 0.5%
0.15% is representative
1 hectare = 3.3 Mg
Atmosphere = 300,000 Mg as N2
![Page 19: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/19.jpg)
Symbiotic Biological Nitrogen Fixation
![Page 20: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/20.jpg)
Rhizobium
Symbiotic Biological Nitrogen Fixation
Symbiosis between plant roots and rhizobium bacteria
![Page 21: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/21.jpg)
Atmospheric Nitrogen FixationAtmospheric Nitrogen Fixation
NN22 + 6H + 6H22 2NH 2NH33
Fixing NFixing N22 is “expensive” is “expensive”
NN NN Triple bondTriple bond– Must use energy to break these bondsMust use energy to break these bonds
Haber - Bosch ProcessHaber - Bosch Process - Artificial Fixation of Nitrogen Gas: - Artificial Fixation of Nitrogen Gas:– 200 atm200 atm– 400-500 400-500 ooCC– no oxygenno oxygen
yield of 10-20%
Produces 500 million tons of artificial N fertilizer per year. 1% of the world's energy supply is used for it Sustains roughly 40% of the population
![Page 22: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/22.jpg)
Plant roots send out signals inviting rhizobia to colonize the root
Rhizobia signal plants to produce an area in which they can colonize
The root produces the area and the avenue to colonize
Area to colonize = meristem
Avenue of colonization = infection thread
Initialization
NN22 + 6H + 6H22 2NH 2NH33
Symbiotic Biological Nitrogen Fixation
![Page 23: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/23.jpg)
Legume root hairs.Chemical signals sent from Root hairs to bacteria: invitation to infect
![Page 24: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/24.jpg)
Root hair
RhizobiumBeginning of infection
Infection thread penetrates root cortex
![Page 25: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/25.jpg)
Root hair curls:Traps bacteria
![Page 26: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/26.jpg)
Nodules on legumes
Packed with N2-fixingbacteria
![Page 27: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/27.jpg)
Bacteroids in nodules
Bacteroids: Rhizobium inNodules
Cells are Fixing atmospheric Nitrogen
![Page 28: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/28.jpg)
Residue from legume crops is usually high in N when compared with residue from other crops and can be a major source of N for crops that follow legumes in rotation.
Most of the N contained in crop residue is not available to plants until microbes decompose the plant material.
Residues from legume crops have low carbon to N (C:N) ratios and are easily decomposed by soil microbes. Residues from non-legume crops have a higher C:N ratio and are slower to decompose
alfalfa range from 100 to 150 lbN/acre
Soybeans range from 20-40 lb/acre
N Contributions
![Page 29: Nitrogen. The most limiting essential element in the environment Nitrogen and Soil Surface soil range: 0.02 to 0.5% 0.15% is representative 1 hectare.](https://reader035.fdocuments.us/reader035/viewer/2022062804/56649f0d5503460f94c21e7e/html5/thumbnails/29.jpg)