Effects Of Agricultural Activities On Ecological System

An ecosystem is defined as a community of plants, animals and decomposers that interact with one another and with the non-living components of the environment, the balance in ecosystem may be interrupted by man through various activities such as

1. BUSH CLEARING: is the act of clearing the bush by cutting down trees, clearing the shrubs and grasses for agricultural activities

EFFECT

– It exposes the soil to direct sunshine which may increase the temperature of the soil which may not favour the microorganism living within

– Removal of plants and trees exposes the soil to the threat of erosion

– Unprotected land or soil is subjected to leaching of nutrient by natural factor

– Extensive bush clearing may lead to desertification

– It may lead to migration or displacement of bush animals

– Bush clearing affects the existing ecosystem and set back succession of plants

– Bush clearing destroys conservation of plants species useful in other way.

2.BUSH BURNING: is defined as a deliberate or in deliberate act of setting the bush on fire either        with a purpose or not at all

EFFECTS

– It kills both animals and microorganism within the engulfed area

– It may lead to gradual loss of soil fertility

– The burnt ashes may give the soil a slight alkaline content

– It will exposes the soil to both wind and rain erosion

– It takes longer time for micro-organism to return to the burnt soil

– It may reduce the water-retaining capacity of the soil

– Some plant species destroyed by the fire may not regenerate again on the soil

– The balanced ecosystem is totally destroyed.

– During burning some of the nutrients vapourise from the soil

            Few Advantages

– It renews the growth of dried up grasses easily (succession_

– It promotes speedy emergency of long dormant seeds of some plants

– the charcoal and wood are used for cooking

3. TILLAGE

This is the activity of preparing the soil for use and growing of crops for consumption, storage and processing or Tillage is the practice of loosening the soil after clearing in preparation for growing. Hoes, spades and plough are used to break the soil

EFFECTS

– Ploughing loosens the soil and exposes it to erosion

– It brings about greater ecological changes of the soil

– Tillage encourages leaching of soil nutrients

– It damages structure and kill some of the micro-organisms

– Tillage increases the risk of fire and direct heat on the soil

              Advantages of Tillage

– It helps in loosening the soil and aid high crop yield

– it prevents appearance of different set of plants

– Tillage enhances proper aeration of the soil

4. FERTILIZER

This is a natural or chemical substance which if spread on the land make plant grow well.

TYPES

– Organic fertilizer is a natural component which may include manure; fish meal and compost which are biologically origin and contain organic material are biologically origin and contain organic material

– Chemical fertilizer are chemical substance that are artificial in nature, they are described by their content e.g. Nitrogen, Phosphorus and potassium (NPK)

   PESTICIDES AND HERBICIDES

A pesticide is a chemical compound used in agriculture to destroy organisms that can damage crops or stored food especially insect and rodent. Examples are insecticide and fungicide

A Herbicide is a chemical substance that kill plant or hamper their growth. It is known as weed-killer. It includes defoliants (contact herbicide) which kill only the parts they touch and selective herbicide which kill only certain plants and spare other.

Insecticides are chemical substance used to kill insects

EFFECTS

– It lead to loss of organic humus

– Chemical fertilizer when permeates can destroy the soil crumb structures

– Chemical such as herbicide and pesticide when washed down to the river can cause water pollution

– Extensive use of chemical fertilizer make soil dry and powdery and make it susceptible to wind erosion

– Chemical fertilizer can kill useful soil organisms when come in direct contact with them

EFFECTS OF DIFFERENT KIND OF FARMING ON ECOLOGICAL SYSTEM

CROP ROTATION

This is a method of farming system which accommodates the division of land into sections and on a different land, a different crop is planted on each section. The method reduces the risk of serious diseases infestations and soil depletion. Legumes are very important in crop rotation as it is believed to restores the nitrogen content of the soil or it adds nitrates to the soil. In crop rotation a surface feeder e.g. maize is planted along with deep feeder e.g. cassava. A surface feeder is a plant which grows near the surface and a deep feeder is a plant with firm root in the soil.

Benefit of crop rotation

– It allows the land to fallow

– It prevents erosion

– It increases the yield or crops

– It prevent disease infestation

– It adds nitrate to the soil

– Nutrients of the soil are not depleted

CROP ROTATION TABLE

	1st plot	2nd plot	3rd plot	4th plot	5th plot
1st Year	Maize	Cassava	Fallow	Groundnut	Yam
2nd Year	Cassava	Fallow	Groundnut	Yam	Maize
3rd Year	Fallow	Groundnut	Yam	Maize	Cassava
4th Year	Groundnut	Yam	Maize	Cassava	Fallow
5th Year	Yam	Maize	Cassava	Fallow	Groundnut

MIXED FARMING

This is the system of farming that integrate both animal production and crop production on same farm.

Benefits

– It allows the animals to convert plant products to high quality protein needed by man

– It allays the fear of single crop failure

– The system is economically viable as the farmer makes money from both crop and animals.

MIXED CROPPING

This is a system of farming whereby the former grows more than one type of crop on a piece of land at the same time.

ADVERSE FARMING METHOD

CONTINUOUS CROPPING

This is a system of farming where a piece of land is permanently put under cultivation of crops

EFFECT

– The system leads of exhaution of essential minerals in the soil

– Cost of clearing is reduced as only an area is prepared for production

– Low productivity may be recorded after some years of using the land.

– There may be possibility of crop failure

MONOCULTURE OR MONOCROPPING:

This is the system of farming that involves practice of growing the same crop on the same piece of land every year.

EFFECT

– It makes the environment unsuitable for many crops after few year

– The system encourages increased spread of both parasite and plant diseases

– The system can lead to crop failure which will affect the farmer financially

– The practices quickens the exhaustion and destruction of soil structure

SHIFT CULTIVATION

This is a system of farming where a piece of land is cultivated for either two or more years until the farmer notices low crop yield and abandons the farm land for another new piece of land.

EFFECT

– It leads to deforestation

– It leads to wastage of land

– it exposes the land to erosion

– It leads to migration of animals