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Form 1 Agriculture Notes on Soil Fertility
Grade/Class: Form 1
Term: Select Term
Document Type: PDF
SOIL FERTILITY (ORGANIC MANURES)
SOIL FERTILITY: ORGANIC MANURES
In the previous lesson you learnt about the supply of water to plants as nutrient.
If one nutrient needed is in low supply, plant growth is limited and crop yield are reduced.
A soil which is able to supply the plant with their nutritional requirements adequately is said to be fertile. Soil fertility is therefore ability of the soil to support and sustain crop growth in order to get maximum yields in a farming system.
Compost manure is made from a mixture of different types of decayed organic wastes
Materials used to make the compost.
Preparation of compost manure in a compost pit
Soil fertility: – ability of the soil to support and sustain crop growth in order to get maximum yields indefinitely
Leaching:- carrying down of soluble minerals from the top soil by infiltrating water beyond reach by plant roots
Soil erosion:-carrying away of top fertile soil
Mono-cropping:– practice of growing one type of crop on a piece of land over a long time
Crop rotation:- practice of growing different crops on same field in an orderly sequence.
Sequence of crop rotation
Maize 1st season
Beans 2nd season
Potatoes 3rd season
Grass 4th season
Inorganic fertilizers:-chemical compounds that are manufactured to supply specific plant nutrients.
Organic manures:- these are fully decomposed organic substances from plant and animal remains added to the soil to provide one or more nutrients
Humus:- end product of decomposition which is mostly dark in color.
Green manure:-type of manure made of green plants when fully decayed.
Farmyard manure: - is a mixture of fully decomposed animal waste (urine and dung) and crop residues
used as animal bedding in animal houses.
Compost manure: - manure prepared from compost (heaped) organic materials.
AIM: To determine how the following affect the quality of farm yard manure.
i.) Type of litter used
ii.) Age of manure
iii.) Age of animal
iv.) Type of feed
Apparatus and materials
- Different types of legumes, grass
- Different types of beddings, straw, legume remains, grass, wood shavings
- Animals of different ages
- Housing-zero grazing unit
Place your animals into four categories as shown below
1 - Mature cow feed it exclusively on grass. place litter of wood savings
2 - Mature cow-feed it on grass and legumes .place litter of wood savings
3 - A calf- feed it on grass and wood shaving on the floo
4 - A calf feed it on grass and legumes
- Remove the beddings after 4 weeks
- Deposit the beddings in a well prepared and shaded place separately
- Replace the bedding in the animal house with a new layer
- Give the manure adequate time to decompose in three or four groups
- Use some of the manure to grow vegetables
Record all the changes that happened to manure and beddings
Record differences noticed between plots grown with different manures
Write a comprehensive report on your project
Tips to teacher on the marking scheme for project
1.The manure changed colour from green to black colour
- The component of the manure are completely decomposed
From the experiment it was noticed that the following affect the quality of farm yard manure
i.)-Type of food eaten
-manure from animals feed on both grass and legumes show better performance compared to that from animals fed on grass only
ii.)-Type of litter used
Where remains from legumes were used the manure gave better results compared to saw dust
iii.)-Age of animals
The calves gave manure of high quality compared to the older cows
iv.)-Method of storage
Manure that was stored in the open lost most of its nutrients by leaching and volatilization. the manure stored under a shed gave higher performance
v.)-Age of farm yard manure
Well rotten manure is rich in nutrients and it is easy to handle and mix with the soil.
Fixation of nutrients.
Ways of loosing and maintaining fertility
Use of manure
Control of soil PH
Use of inorganic fertilizer
Change of soil PH
By the end of the lesson, you should be able to:-
* define soil fertility
* distinguish between organic matter and manure
* explain how soil fertility can be maintained
* explain how soil looses fertility
* explain the importance of organic matter in the soil
* describe the different organic manure well
* prepare compost manure.
* prepare compost manure.
* Characteristic of fertile soil
* Problems of manures
* Importance of manures
* Importance of organic matter
* Ways in which soil loose/gain fertility
* Green manure
* Farm yard manure
* Compost manure
What is soil fertility ?
Ability of the soil to support and sustain crop growth in order to get maximum yields indefinitely Maintaining soil fertility What is crop rotation? Crop rotation is practice of growing different crops on same field in an orderly sequence over given period of time. This is one way of maintaining soil fertility
Characteristics of a fertile soil
Good depth:-Deep soil gives plant roots greater volume to obtain plant nutrients and provide strong anchorage
A well drained soil is properly aerated promoting healthy root development. Well aerated soils allow root respiration and reduce the build up of carbon dioxide to toxic levels.
Good water holding capacity:-
This ensures that enough water is retained for plant use.
Adequate nutrient supply:-
It should supply the nutrients needed by plants in the correct amount and in form that is available to the crop
Correct soil pH:-
Different crops have different soil pH requirements. Certain plant nutrients are only available at a specific soil pH.
Pests and diseases:-
Free from excessive infestation of soil borne pests and diseases
Deep soil gives plant roots greater volume to obtain
Ways of maintaining soil fertility
* Crop rotation
* Proper drainage
* Weed control
* Use of manure
* Mixed cropping
* Control of soil PH
* Use of inorganic fertilizer
Ways of loosing soil fertility
* Soil erosion
* Salt accumulation
* Change of soil PH
* Burning vegetation
Characteristics of organic manure
Soil fertility is usually improved by use organic manure.
Humus- end product of decomposition which is mostly dark in colour.
These are fully decomposed organic substances from plant and animal remains added to the soil to provide one or more nutrients.
Advantages and disadvantages of organic manures.
Are readily available and cheap
Add plant nutrients to the soil
Do not pollute the soil
Improve water holding capacity of the soil
Prevent soil from being overheated
Support life of tiny animals living in the soil.
Manures are bulky to handle
Some crop diseases, pests and weeds may be spread through manures
A lot of labour is required to apply manure onto a farm
Types of organic manure
There are three types of organic manure namely:
* Farm yard manure
* Green manure
Farm yard manure
Farm yard manure is made up of animal wastes and bedding from animal houses
Factors which affect the quality of farm yard manure are :-
* Type of litter used
* Age of manure
* Age of animal
Harvesting materials for green manure
Factors which affect the quality of green manure
* Type plant material
* Age plant growth
* Fertility of the area where material were grown
Type of litter used
Age of manure
Age of animal