-
This is default featured slide 1 title
Go to Blogger edit html and find these sentences.Now replace these sentences with your own descriptions.This theme is Bloggerized by Lasantha Bandara - Premiumbloggertemplates.com.
-
This is default featured slide 2 title
Go to Blogger edit html and find these sentences.Now replace these sentences with your own descriptions.This theme is Bloggerized by Lasantha Bandara - Premiumbloggertemplates.com.
-
This is default featured slide 3 title
Go to Blogger edit html and find these sentences.Now replace these sentences with your own descriptions.This theme is Bloggerized by Lasantha Bandara - Premiumbloggertemplates.com.
-
This is default featured slide 4 title
Go to Blogger edit html and find these sentences.Now replace these sentences with your own descriptions.This theme is Bloggerized by Lasantha Bandara - Premiumbloggertemplates.com.
-
This is default featured slide 5 title
Go to Blogger edit html and find these sentences.Now replace these sentences with your own descriptions.This theme is Bloggerized by Lasantha Bandara - Premiumbloggertemplates.com.
37 corps members escape death in Ogun accident
Ways by which soil looses it fertilization
Ways by which soil looses it fertilization
* Bush burning : This kills many soil microorganisms such as bacteria and worms which are involved with nutrients production.
* Harvesting : When crops are harvested, the nutrients they contain are lost from the soil.
* Soil erosion : This is the loss of top soil and as such loss of soil nutrients.
* Continuous cropping : Planting of crops from year to year on the same portion of land which leads to loss of nutrient.
* Leaching : When the soil does not retain water well, percolating water carries nutrients beyond the reach of plant roots.
Different types of erosion
Erosion of land can occur in a variety of different ways which includes
1. Water erosion : The beating action of rain falling on wet soil destroys surface aggregate and also reduce the amount of infiltration of water. Once the infiltration rate is exceeded by rainfall, surface run off takes place down the slope.
The longer and steeper the slope, the greater the erosive power of the run off. As it flows down slope, water takes into suspension first the clay and silt and as it picks up speed, it takes up progressively coarse materials.
2. Wind erosion : Wind erosion starts with a process Known as saltation; which is a sort of jumping motion of the smallest ,most erodible particles or aggregate of soil.
Particles which becomes airborne in gusts of wind fall gradually back to the ground after covering a distance of three or four meters. The impact of these particles hitting the ground moves other particles of similar and larger size.
The larger particles slide and roll along the surface until stooped by ditches while the finer materials are projected higher into the air to form dust clouds.
3. Glacier erosion : Glacier are giant bodies of ice that pick up huge pieces of rock, some even as big as houses. A combination of the water, ice and picked up sediments creates a powerful eroding machine. As more sediment is picked up, the force of erosion becomes greater.
The erosion can smooth out areas that were once rugged and rocky. Glaciers are such a powerful force that they can carve out valleys or create land forms such as deltas.
4. Soil erosion : Flooding, wind etc, can carry the top soil away and make the soil fertile. When forest are cleared for timber or to make room for agriculture, the rate of soil erosion can increase dramatically because trees are no longer there to hold the soil in place. Increased erosion can cause streams and rivers to become clogged with silt, which harms or kill aquatic animals.
Also overgrazing by herbivores can lead to soil erosion because grasses are very efficient in holding down and stabilizing soil..
Measures to check soil erosion
* Reforestation is the restocking of existing forests and woodlands that have been depleted. The tree roots serve to anchor the soil and prevent erosion.
* Contour plowing is the farming practice of plowing across a slope following its elevation contour lines. The rows formed slows water run-off during rainstorms to prevent soil erosion.
* planting of perennial plants which have deep, extensive root systems can help hold soil in order to prevent erosion.
* Terracing is used in farming to cultivate sloped land. Terraced fields decrease erosion and surface run off and are effective for growing crops requiring much water such as rice.
Ways to conserve soil fertility
* proper soil management involving an adequate soil conservation program.
* Adding of green manure
* Inclusion of leguminous plants to provide free nitrogen
Maize cultivation
Maize cultivation
Maize is only known in the cultivated state and is believed to have originated in Mexico in prehistoric times. It currently has world wide distribution and is grown where summer ate reasonably warm.
Africa, Asia, and America are the most likely countries of origin. Processed corn is consumed as a snack or cereal by man and may also be used as silage to feed livestock.
Soil types preferred by maize
Some of the major soil types preferred by corn include alfisols, entisols and inceptisols. The soil PH in maize fields range from 5.8 to 6.5 in the alfisol and 6.2 to 8.1 on vertisols.
These soils are characterized by low organic carbon contents, weak soil profile development, coarse or medium textured upper layers of soil and low microbial load attributable to the low organic carbon.
The afisols are prone to high phosphorus fixation. Corn prefers deep, naturally rich, easily tilled soil. The soil should be free from restrictive layers (hard pan) and soils with PH lower than 4.5 should be avoided or corrected by the application of lime.
The most suitable soil type for maize is a soil with good effective depth, favourable physical properties (texture and structure), good drainage, optimal moisture regime and sufficient and balanced quantities of plant nutrients.
Method of cultivation
Maize is propagated from seeds. A deep, firm seedbed, free of clods and surface irregularities should be prepared preferably on moderately heavy to heavy soil. Soil should be worked and dialed about 3-4 weeks before planting, thus allowing for partial decomposition of organic materials.
Planting depth varies from 5-10cm, depending on the soil type. Planting should be shallower in heavier soils than in Sandy soils.
Weed control during the first 6-8 weeks after planting is crucial, as weeds compete vigorously with the crop for nutrients and water during this period.
The presence of weeds during harvest may hinder the process and transmit odors to grain which incurs additional cost for removal.
The visible sign of the maturing maize plant is senescence, dying back of leaves starting from the lower leaves and continuing upwards.
This is the period of grain drying which can progressively be monitored through the kernel milk line. The disappearance of the milk line denotes that the grain has reached physiological maturity. The appearance of the black layer at the tip of the kernel (detachment of kernel from cob) denotes harvestible maturity.
Major disease of maize
Some fungal diseases of maize include gray leaf spot (cercospora zeamaydis), anthracnose leaf spot (colletotrichum graminicola), common corn rust (puccinia sorghi).
Solution to diseases
The above fungal diseases can be managed by treating the seed with fungicides, planting when soil conditions are warmer and drier, use of proper planting depth, use of resistant hybrids and crop rotation.
Library and information
The Library
* National library
* Public library
* Academic library
* Special library
* School library
* Digital library
National library
The national library is the library of other libraries. It Is established and maintain by the federal government.
The national library has the responsibility of carrying out bibliographic control. In the national library you read and review but not permitted to carryout.
Public library
Public libraries are libraries established and maintained by public funds, There is no discrimination and restriction to public library.
Academic library
The academic library are attached at the higher level or institution .
Academic library are information centers established in support of the mission of their parent institutions to generate knowledge, and equip people with knowledge in order to serve the society and advance the well being of mankind.
Special library
Special library refers to those libraries that are established to serve the needs of a special group of people with similar interests, examples are medical libraries, law libraries etc.
School library
A school library identifies, collects,processes,organizes,stores,preserves and disseminated information relevant to the needs of the teachers and pupils.
The library is attached to the primary and secondary school modern to develop the culture and the reading habit of pupils and students.
Digital library
A digital library is a library in which collections are stored in formats as opposed to print and other media's which are accessible by computers . The contents may be stored locally or accessed remotely.
The digital library provides more choices, enhances flexibility and often provides the learners with instant feedback.
The system of government
The systems of government
Federal system
Confederate system
Unitary system
Presidential system
Parliamentary system
Federalism/federal system of government
This is a system of government that involves the constitutional sharing of power from the central or federal government to its component units.
The units of the federal government are;
(a) The exclusive list: This is where the federal government have the absolute power to legislate. (Eg) defense, printing of currency, custom.
(b) The concurrent list: This is where the federal or state government legislate on but If there is a clash of interest the federal government takes control.
(c) The residual list: This is where the state government has absolute power on (Eg) markets
.m; primary health care
Characteristics of federalism /federal system
* There is constitutional sharing of power between the central government and it's components units.
* The federal government is stronger than the component units.
* They have rigid constitution
Confederal system of government
This is a system of government whereby the component units are stronger than the central units.
Characteristics of Confederal system of government
* The component units are stronger than the federal government
* It could lead to sensuality or break away
* It has rigid constitution
Unitary system of government
This is a system of government whereby the ultimate power of the state is in the hands of a person or group of persons for administrative convenient.
Characteristics of unitary system of government
* There is no constitutional sharing of power
* The constitution is flexible
* It has autocratic system of government
The presidential system of government
This is a system of government whereby an individual is both the head of state and also the head of government. He the sole executive and commander in chief of arm forces.
Characteristics of presidential system of government
* The sole executive
* There is separation of power
* The president performs both ceremonial and executive functions
The parliamentary system of government
System development life cycle (SDLC)
System development life cycle (SDLC)
what is system development life cycle?
The system development life cycle (SDLC) is the traditional system development method that firms use for huge scale IT projects.
The SDLC is a structured framework that consists of sequential processes by which an information system is developed.
It has the following stages;
* System Investigation /planning
* System Analysis
* System Design
* System Implementation
* System Evaluation
* System Maintenance
Once a development project has the necessary approval from all participants, the systems analysis stage begins.
System analysis is the examination of the business problem that an organization plans to solve with an information system.
The main purpose of the systems analysis stage is to gather information about the existing system in order to determine the requirements for an enhanced system or a new system.
When the system developers have accumulated the user requirements for the new system, they proceed to the system design stage.
The system development life cycle (SDLC) is also a term used in system engineering, information systems and software engineering to explain a process of planning, creating, testing, and deploying an information system.
The systems development life cycle concept applies to a range of hardware and software configurations, as a system can be composed of hardware only, software only, or a combination of both.
SDLC can be used during the development of an IT project, it describes the different stages involved in the project from the drawing board, through the completion of the project.
A system development life cycle is composed of a number of clearly described and distinct work phases which are used by system engineers and system developers to plan for design, build, test, and deliver information systems.
Like for instance like anything that is manufactured on an assembly line, an SDLC aims at producing high-quality systems that meet or exceed customers expectations, based on customer requirements, by delivering systems which move through each clearly defined phase, within the scheduled time frames and cost estimation.
Phylum hemichordata
![]() |
| Phylum hemichordata : |
![]() |
| Acorn worm(saccoglossu) |
Class pterobranchia : They exhibit a dorsal extension of the pharynx,forming an anterior stimichord just like the enteropneusta, which serves to support the surrounding tissues. However, they differ from the enteropneusts by possessing ciliated, anterior tentacles and a U shaped gut. Although, most members of this group have rigid tubes that they secretes e. g. Cephalodiscus.
Phylum echinodermata
![]() |
| Phylum echinodermata: |
Preservation of animal species
![]() |
| Preservation of animal species |
Preservation can be defined as the use of chemical, physical or other Processes to prevent microbial
and physical damages to biological specimens with a view of retaining their original form and prolonging their storage life.
The procedure for preservation of animal specimens varies greatly from one animal group to another.
In most cases, the animal must first be killed or narcotised in a suitable way so as to leave the tissues in a state ,which is proper for display.
The specimen is then fixed in this condition and finally preserved. This final preservation is normally made either in a solution of ethanol or methanal (formalin).
Techniques in fixing and preserving animal materials
Fixation is a chemical process, which stops autolysis and stabilizes protein components of tissues so that in
subsequent processing the tissue retains as fully possible the form they had in life.
Preservation allows materials to be stored indefinitely by destroying any microbial action, which could degrade the specimen.
The choice of fixation will depend upon the animal material to be fixed and the purpose for which it is being fixed.
Narcotisation :This is also known as relaxation and is an interim technique for animals since many are highly contractile and assume grossly distorted postures if placed straight into fixative.
Hardening: Some chemical like ethanol is particularly liable to cause tissues to harden on prolonged exposure to high concentration.
Shrinkage :Certain fixatives such as ethanol and mercuric chloride cause tissues to shrink thus distorting the specimen significantly.
* A 5-10%v/v aqueous solution of formalin(=40% v tv aqueous formaldehyde neutralized with calcium carbonate to prevent any acidity in the solution resulting in the slow dissolution of calcareous structures.)
*50-70% ethanol : Ethanol is inflammable, highly volatile and tends to cause shrinkage and decolorization in soft bodied animals. Pass them slowly through a graded series of concentrations to minimize this problem.
Dry preservation
This form of preservation is used mainly for vertebrate taxidermy and for arthropods and other invertebrate species. The hard exoskeleton of arthropods are easily preserved in dry state since the skeleton prevents collapse and loss of form upon drying.
Taxidermy : it is a type of dry mounting where the vertebrate is carefully skinned to remove the body and then replace with false body made of polystyrene, foam or cork etc.
Storage : Careful maintenance of specimen after fixation /preservation process is very important. The storage conditions for materials preserved either in wet or dry state.
Labelling : labelling must be comprehensive and contain information on the fixative and preservation processes as well as ecologically and taxonomic details.
*it prevents the attack of micro–organisms like bacteria and fungi that causes spoilage.
* it helps in the preservation of large quantities of specimen needed for laboratory studies.
*extinct animals specimens can be preserved for future study.
fractional distillation of crude oil
![]() |
| fractional distillation of crude oil |
Reaction of ethanoic acid
![]() |
| Reaction of ethanoic acid |
idioms
![]() |
| Idiomatic expression |
figures of speech
parts of speech
petroleum
Study skills
![]() |
| Study skills |


























