西北农林科技大学：《植物营养学》课程教学资源（PPT课件讲稿，英文版）Chapter 15 Organic fertilizers

Chapter 15 Organic fertilizers

Chapter 15 Organic fertilizers

Concept of organic fertilizers Organic fertilizers-that are derived from the wastes and residues of plants or animals Such as manure, sewage sludge etc Some consist of unprocessed plant materials(such as tree leaves grass clipping, crop residues, and green manure crops Others have been processed, by industry(cannery wastes), by animals(manure, litter, blood, bone, offal+j, sewage sludge))or by microbes(leesYA* from fermentation, composts) Some organic materials, particularly composted manures and sludge, are sold as soil conditioners and do not have a nutrient quarantee stated on the package, although small amounts of nutrients are present

Organic fertilizers – that are derived from the wastes and residues of plants or animals. Such as manure, sewage sludge etc. Some consist of unprocessed plant materials (such as tree leaves, grass clipping, crop residues, and green manure crops) , Others have been processed, by industry (cannery wastes), by animals (manure, litter, blood, bone, offal废物, sewage sludge)) or by microbes (lees渣滓 from fermentation, composts) Some organic materials, particularly composted manures and sludge, are sold as soil conditioners and do not have a nutrient guarantee stated on the package, although small amounts of nutrients are present Concept of organic fertilizers

Characteristics of organic manure Compared to synthetic fertilizer formulations organic fertilizers contain 1. Relatively low concentrations of actual nutrients 2. They have some organic matter 3. The most of nutrient is slow releasing 4. they have more kinds nutrient than mineral fertilizers

Characteristics of organic manure ▪ Compared to synthetic fertilizer formulations, organic fertilizers contain ： ▪ 1. Relatively low concentrations of actual nutrients ▪ 2. They have some organic matter. ▪ 3. The most of nutrient is slow releasing. ▪ 4. they have more kinds nutrient than mineral fertilizers

Benefits of manure 1. The use of manure helps to maintain the organic matter content of the soil Which can improve soil structure and Water infiltration and allows more air to get to plant roots 2. Where organic sources are used for fertilizer, bacterial and fungal activity increases in the soil 3. Nutrient release by microbial activity, in general, occurs over a fairly long time period

Benefits of Manure ▪ 1.The use of manure helps to maintain the organic matter content of the soil which can improve soil structure and water infiltration and allows more air to get to plant roots. ▪ 2.Where organic sources are used for fertilizer, bacterial and fungal activity increases in the soil. ▪ 3.Nutrient release by microbial activity, in general, occurs over a fairly long time period

Possible Disadvantages 1. f there is an immediate need for nutrients, organic fertilizer cannot supply them in a hurry 2. Manure commonly contain 4 to 5% soluble salts(dry weight basis)and may run as high as 10%. To illustrate, an application of 5 tons of manure containing 5% salt would add 500 lbs of salt

Possible Disadvantages ▪ 1. If there is an immediate need for nutrients, organic fertilizer cannot supply them in a hurry. ▪ 2. Manure commonly contain 4 to 5% soluble salts (dry weight basis) and may run as high as 10%. To illustrate, an application of 5 tons of manure containing 5% salt would add 500 lbs. of salt

Possible Disadvantages 3. Weed seeds are common in some manure 4. One should avoid using pig, dog or cat feces because of the problems involved with internal parasitic worms as 生虫 which may be transferred to humans if not composted 5. The possibility of nitrogen depletion is another drawback of organic fertilizers

▪ 3. Weed seeds are common in some manure. ▪ 4.One should avoid using pig, dog or cat feces because of the problems involved with internal parasitic worms寄 生虫 which may be transferred to humans if not composted. ▪ 5. The possibility of nitrogen depletion is another drawback of organic fertilizers. Possible Disadvantages

Possible Disadvantages 6. An application which is too heavy or too close to the roots of the plants, especially immature manure may cause burning ( actually a process of desiccation千燥by the chemical salts in the fertilizer)生粪咬苗 7. The nutrient concentration of organic manure can vary widely, and information on the amount of nutrients and the exact elements in an organic fertilizer is not readily available to the farmers

▪ 6. An application which is too heavy or too close to the roots of the plants , especially immature manure may cause “burning” (actually a process of desiccation干燥 by the chemical salts in the fertilizer)生粪咬苗. ▪ 7. The nutrient concentration of organic manure can vary widely, and information on the amount of nutrients and the exact elements in an organic fertilizer is not readily available to the farmers. Possible Disadvantages

Farmyard manure(GFYM)厩肥 FYM is a mixture of partially decomposed straw containing faeces and urine The production of livestock slurries has thus increased The nutrient concentration of organic manure can vary widely depending much on their source and moisture

Farmyard manure (FYM)厩肥 ▪ FYM is a mixture of partially decomposed straw containing faeces and urine. ▪ The production of livestock slurries has thus increased. ▪ The nutrient concentration of organic manure can vary widely depending much on their source and moisture

Characteristics of farmyard manure Manure is an excellent fertilizer containing nitrogen, phosphorus potassium and other nutrients It also adds organic matter to the soil which may improve soil structure, aeration, soil moisture-holding capacity, and water infiltration

Characteristics of farmyard manure ▪ Manure is an excellent fertilizer containing nitrogen, phosphorus, potassium and other nutrients. ▪ It also adds organic matter to the soil which may improve soil structure, aeration, soil moisture-holding capacity, and water infiltration

Nutrient concentrations in organic manure K Ca Organic manure moisture mg/g fresh matter FYM 760 5.0 54 42 Cattle slurry 0.7 3.2 Pi 1g Slurry 2.0 1.0 2.0 Sewage sludge 550 8.3 2.2 0.4 0.7

Nutrient concentrations in organic manure1 N P K Ca Mg Organic manure moisture mg/g fresh matter FYM 760 5.0 1.1 5.4 4.2 1.1 Cattle slurry 930 3.1 0.7 3.2 1.1 0.4 Pig slurry 970 2.0 1.0 2.0 - - Sewage sludge 550 8.3 2.2 0.4 0.7 -