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Land Reclamation and Rehabilitation - Geography Form 4




Objectives

By the end of the session, you should be able to:
a) Identify different methods of land reclamation
b) Describe the methods of land reclamation

Land reclamation and rehabilitation

Land reclamation is the process by which wasteland such as a desert is converted into useful land fit for cultivation and other economic activities. Land rehabilitation is a process of restoring land to its former productive state.




Video clip of an area where the forests have been cleared and then a planted forest

Methods of land reclamation in Kenya


Irrigation

Irrigation is the artificial supply of water to plants to enhance their growth. it is thus practiced in areas where there is little rainfall.

    Water lifting methods

    The water is scooped from water source like a canal or a well by buckets and splashed onto the crops. This method is used on a small scale such as in kitchen gardens or to water crops that are grown adjacent to water sources.


    Flood irrigation

    It is also called basin irrigation. Basin irrigation heavily depends on the annual flooding of a river. During floods, the flood waters are allowed to move into ditches and spread out over the flood plains through the force of gravity. In Kenya it is used in Mwea Tebere Irrigation scheme and Ahero Irrigation Scheme and Lower Nyakach.

    Sprinkler or Overhead irrigation:

    This is where water under pressure from a central water supply line through a pipeline is supplied to the plants from above.


    Canal irrigation

    Canal irrigation is where canals are dug. Furrows are cut to lead water from the rivers and storage reservoirs into the farms. In Kenya this method is practiced in Mwea irrigation scheme.


    Trickle irrigation.

    This is where water is applied to individual plants through well laid plastic pipes with holes at specific intervals through which water trickles to the base of the plants.

    Drip irrigation

    In drip irrigation bottles filled with water are inverted into the roots of plants. The plant slowly saps the water from the bottles. This method is commonly used in low rainfall areas to grow trees, fruits and flowers.

    Drainage of swamps

    This is a method of reclaiming land by removing excess water from an area that is waterlogged. This can be done by constructing ditches, canals and dykes.

    Control of tsetse flies

    A tsetse fly is an insect similar to a house fly. It is a carrier of sleeping sickness in human beings and Nagana (Trypanosomiasis) in cattle which may be fatal. The fly has caused large stretches of fertile land to be abandoned. The control measures applied include bush clearing, insecticide application, sterilization of male tsetse flies and traps.

    Afforestation

    This is the process of planting trees in an area where there has never been trees. Forests help to improve the productivity of the land in the following ways.

    • Protecting the soil by controlling soil erosion that is caused by running water and wind.
    • Protecting water catchment areas.
    • Improving the climatic environment.

    Planting of drought resistant crops.

    Drought resistant crops consist of plants that require little moisture to grow and are able to withstand conditions of prolonged high temperatures. These crops are therefore grown in marginal lands of Kenya which experience semi arid conditions, but have a high potential for agriculture . They include areas like Kitui, Machakos, Tharaka, Kilifi and Taita Taveta to mention but a few.

    Rehabillitation

    Various methods are used to restore the affected portions of land into their former productive states.The methods include

    • Afforestation and reafforestation.
    • Bush fallowing
    • Planting grass strips and cover crops
    • Mulching
    • Bunding
    • Manuring

    Let us now discuss each of these methods


    Afforestation and reafforestation.

    Afforestation is the practice of planting forests or trees in areas where none existed. Reafforestation is when the trees are replaced after being cut. Trees play an important role in the conservation of soil and water in the environment.

    Bush fallowing

    Bush fallowing involves cultivating a field for a period of two to three years after which it is left fallow while the farmers moves on to another piece of land.During the fallow period the soil is able to recover its fertility. It is practised in areas that are sparsely populated like Voi and Mariakani.

    Planting grass strips and cover crops

    Grass strips or cover crops spread on the ground to cover it, therefore the land is protected from erosion and more water percolates through the soil.

    Mulching

    Mulching takes place when vegetable remains, plant litter and dry grass or polythene sheets are used to cover the soil. The mulch helps to:-

    • retain of moisture to
    • reduce evaporation
    • reduce soil erosion especially splash erosion
    • increase water infiltration in the soil
    • soil nutrient and organic matter are obtained as the mulch decompose

    Bunds

    These are ridges of soil piled across a slope on which plants can be grown. They help to check surface runoff and increase infiltration

    Manuring

    Manuring is done through constant application of animal or vegetation manure and chemical fertilizers which improve the fertility of the soil directly.

    Irrigation schemes in Kenya

    Objectives

    By the end of the session you should be able to identify various irrigation schemes in Kenya

    Irrigation schemes in Kenya

    There are many irrigation schemes in Kenya growing a variety of crops as shown by the map below.

    Mwea irrigation scheme

    Mwea irrigation scheme is located in Kirinyaga county at the foot hills of Mount Kenya.


    Factors that favoured the location of the scheme

    Physical factors

    The presence of black cotton soils which suitable for rice cultivation due to high water retention capacity.

    The gently sloping land allows the water to flow to the field by gravity. This undulating land also allows for mechanization.


    The presence of rivers Thiba and Nyamidi which provide regular and abundant water for irrigation throughout the year.

    The area receives low and unreliable rainfall which cannot sustain crop production thus necessitating the use of irrigation.

    Availability of extensive land with sparse population made the project viable since there was room for future expansion.

     

    Human factors

    • The area was sparsely populated due to its semi- arid conditions, therefore displacement of people was minimal.
    • The colonial government needed a project to occupy the political detainees during the state of emergency in 1952.
    • The availability of labour by the former detainees and from the surrounding areas with high population
    • Large market for the rice available from the nearby urban centers like Embu, Nyeri, Kerugoya and Nairobi.

    Organization of the scheme

    There should be a visit to the scheme to get the most recent organization of the scheme covering cultivation, marketing and management.

    Significance of Mwea irrigation scheme

    • It saves the country's foreign exchange which could have been used to purchase ricefrom other countries.
    • The scheme has provided settlement for many people.In Reference to 2009 Kenya population census report.
    • Annual floods have been corrected in the reservoirs created for irrigation.
    • There is enhanced food security
    • Alleviation of poverty among the people since they are engaged in cultivation and selling of rice.
    • The scheme has led to the effective use of land which was originally barren
    • The farmers also grow other crops like peas, tomatoes, beans and maize for their livelihood.
    • Infrastructure has been improved since roads have been built to transport the rice from the field to the market.
    • Social amenities such as schools and hospitals have been provided and this has improved the living standards of the local people.
    • The scheme offer employment to many people thus have raised the living stardards.

    Physical problems

    Stagnant water in the scheme encourages the breeding of snails and mosquitoes which cause diseases like bilharzia and malaria respectively.


    Siltation and the growth of weeds

    Siltation and the growing of weeds in the canals interfere with the flow of water into the field.


    Pests

    Pests such as case worm, stock eyed fly, leaf minor and quelea birds attack the crop lowering the yields.


    Diseases

    Diseases such as leaf streak, leaf grain rot, rice blast downing meldew affect the rice grain.


    Solutions of the named problems

    • The problem of unplanned irrigation expansion can be solved by building more reservoirs.
    • Farmers are being trained to participate in managing the irrigation water through water users association.
    • Improve on the marketing strategy in order to get better prices to enable them to hire labour.
    • The national cereals and produce board to market rice on behalf of the farmers for prompt payment.
    • To empower the cooperative societies and have them supply inputs and extend credit facilities to the farmers.
    • The government should facilitate the expansion of the scheme.
    • The government should look into ways of expanding the scheme. The local people should also be encouraged to use population control methods.
    • The National Cereals and Produce Board should help farmers In marketing their produce while the national Irrigation board provides them with high quality seeds.
    • The farmers should deliver their rice to Mwea rice stores so that they will fetch better prices.
    • Research by  National Irrigation Board to develop high quality seeds should be done in order to ensure the Basmati variety has its characteristic aroma. The National Cereals and Produce Board will ensure the supply of quality rice.

    Human Problems

    Unplanned irrigation expansion has led to increased demand for irrigation water which the three rivers cannot sustain. Some water has also been diverted to horticultural farming.

    Shortage of labour experienced during the planting and harvesting season.



    Delayed payment

    Delayed payment lowers the morale of the farmers making them abardon rice for other crops.

    The co-operation societies which replaced the NIB failed to supply inputs and credit to the farmers. This led to practice of leasing out all or part of their farms.

    Shortage of extension officers makes it difficult for the farmers to get technical advice

    The scheme has become overpopulated. This has created pressure on the existing facilities including water for irrigation.


    Political interference has alienated the management with the farmers. This has created land ownership conflict making ,management difficult.

    The liberalized marketing of rice led to overexploitation by middle men.

    The use of uncertified seeds has lowered the quality of rice produced for example the basmati rice lacks the original aroma.

    Possible solutions

    • Spraying the stagnant water with insecticides to reduce the breeding rate of the snails and mosquitoes.
    • Weeds can be controlled by herbicides sprayed on them.
    • Dredging is done to remove the silt from the canals.
    • Use of certified seeds which are free from pests and diseases.
    • There is quelea control unit which monitor the movement of the birds in order to control them. Various methods such as poisoning and use of explosives for scaring the birds are applied.





    Land reclamation and rehabilitation

    Objective

    By the end of the session you should be able to compare methods of land reclamation in Kenya and  Netherlands.

    Land reclamation in Netherlands

    The Netherlands , also called Holland, is one of the countries in western European. Most of the coastal land in the country has been reclaimed from the sea.



    The following stages were used in the reclamation of land from the sea.

    Stage 1: construction of protective dykes or walls to enclose the part of the sea to be reclaimed and protect the area from getting flooded during high tides.
    Stage 2:Ring canals were constructed to carry water from the area to be reclaimed back to the sea.
    Stage 3:pumping stations were installed to pump out water from the sea enclosed by the dyke.
    Stage 4:water was pumped out of the area enclosed by the dyke.
    Stage 5:Reeds were sown to prevent weed from growing. They were also meant to use up the excess water and reduce salinity.
    Stage 6:drainage ditches were cut in the land and drainage pipes laid. More pumping stations were put up on the land being reclaimed. These were used to drain water from the water table.
    Stage 7:The area was divided into rectangular portions using inner dykes and ring canals.
    Stage 8:The soil was treated with chemicals to lower the salinity.
    Stage 9:The drained land was flushed with fresh water to remove salt from its soil.
    Stage 10:pumping out of the water from the polders was a continuous process. This was to prevent the water from accumulating in the reclaimed land.

    Animate each and every stage to show the various changes taking place.

    Two projects that were successful in reclaiming land from the sea in the Netherlands are the Zuider Zee to the North and Delta plan in the south western region.We now look at the benefits of the Zuider Zee project. The following are some of the benefits of the Zuide Zee project.

    • A large water lake Ijssel was created. It supplied water to the surrounding area for domestic, industrial and irrigation.
    • The floods in the area were controlled through the canals, ditches and pumping stations.
    • Land reclaimed has increased arable land for crop cultivation and dairy farming.
    • The road distance between north and south Holland has been shortened.
    • Soil salinity l has been reduced because of the fresh water from the lake this has lead to an increase in crop and livestock production.

    Benefits

    The following are the additional benefits of delta plan region.
    1. The salination of inland fresh water was controlled by damming the inlets.
    2. The formerly isolated islands of Zeeland were connected to the mainland.
    3. Recreation facilities and tourist attractions increased in the area.

    Land reclamation in Kenya and Netherlands can be compared in the following ways.

    • In Kenya it is done on a small scale while in the Netherlands it is done on a large scale.
    • In Kenya it is both on dry and swampy land while in the Netherlands it is from land flooded by sea water.
    • The methods of land reclamation in Kenya includes draining of swamps by digging ditches, channels and diversion canals, irrigating arid and semiarid areas clearing of jungles and bushes and afforestation while in the Netherlands the methods involved construction of dykes, ring canals, drainage ditches and planting reeds after pumping sea water from the land.

    Conservation
    The conservation measures undertaken include

    • establishment of game reserves, National parks and game sanctuaries
    • Establishment of anti- poaching unit.
    • Ban on game hunting and trading in game products
    • Establishment of game ranches
    • Fencing of forests and national parks
    • Nongovernmental organizations initiatives
    • Gazettment of forests
    • Eco- tourism and pollution control
    • Rehabilitation if land damaged by mining and soil erosion
    • Research

    We shall now discuss these conservation measures.     

    • Establishment of game reserves, national parks and game sanctuaries.

    Land has been set aside for the above and gazetted to enjoy government protection against destruction by people. For example Kenya has 23 National parks, 4 marine parks 6 marine reserves, 28 national reserves and 5 national sanctuaries occupying a total of 47,674km2.

    • Establishment of anti poaching units

    The government has set aside anti poaching units which are manned by well trained paramilitary personnel with the responsibility of tracking down and arresting poachers.
    Provide a video clip of Solio ranch and galena ranches, Kikopei game ranch at Gilgil.

    • Ban on game hunting and trading in game products.

    In east Africa the hunting of wild game is prohibited so as to allow for their population increase. In 1978 trade of all wildlife products was banned in Kenya. Example of such products are the rhinoceros horns , hippopotamus teeth, elephant  tusks, crocodiles, leopard, lion and zebra skins. This was to reduce poaching. The east African countries are signatories of international convention that prohibits game products.

    • Establishment of game ranches.

    Game ranching refers to protected large tract of land, together with the necessary personnel, buildings and equipment for rearing a specific kind of wild animals.
    These ranches have been established to exploit wildlife for meat and other products while at the same time conserving. For example Galana game ranching research on the boundary of the Tsavo East National park in which eland , Oryx and buffalo are raised, Solio ranch in Laikipia and Nyeri county.

    • Fencing of forests and National parks.

    Forests reserves , National parks and sanctuaries are fenced off so as to limit human interference.

    • Non-governmental organizations initiatives

    The organizations have played key roles in the conservation of wildlife in the East African region. For example the world wildlife fund (WWF) which has given support to the lake Nakuru National Park in Kenya.
    Other organizations are ;  National save the rhino project
    Kenya rhino rescue project and conservation strategy and management plan for the black rhinoceros. The youth for conservation is also an NGO which conducts regular desnaring in major National parks in Kenya, besides conducting public awareness programmes.

    • Conservation of forests

    Forests are homes of many wild animals and birds. There are also many species of trees.
    Forestry and wildlife conservation in these areas go hand in hand and if properly managed may increase the income from tourism. For example Kakamega forest, Meru forest and Karura forest.
    Insert a photo of Karura forest.

    • Eco tourism and pollution control

    Eco-tourism in an environment friendly tourism where by a tourist enjoys watching what nature has provided for enjoyment while at the same time protects what nature has provided.
    Eco-tourism enhances conservation of the wildlife through reduced construction of facilities such as lodges, roads and airstrips into parks.
    Through eco-tourism proceeds from tourism are shared with local communities hence encouraging them to conserve wildlife for example the Mwaluganje elephant sanctuary in Kwale.
    Provide a documentary interviewing the local community benefiting from Mwalangaje elephant sanctuary
    Do a documentary of Kenya range land ecological monitoring unit (KREMU) head quarters is in Nairobi.

    • Rehabilitation of land damaged by mining and soil erosion.

    The rehabilitation of land after severe soil erosion and mining has been put into economic use especially where suitable wildlife has been introduced for example bamburi cement company has rehabilitated waste land after mining of limestone to create Hallers park.
    Provide a video clip of Hallers Park at Bamburi

    • Research

    Some research centers have been established to research on wildlife feeding habits diseases reproduction rates, lifespan and conditions needed for their habitation. For example there is a unit established by the government called Kenya Rangeland Monitoring Unit (KREMU)

    Exploitation of natural resources.

    Availability of transport and communication opens up remote areas for economic activities such as mining, fishing, tourism and trading.
    Provide a video clip of the area around Magadi and the industry.

    The concluding remarks on transport and communication will high light the problems facing transport and communication.

    Government policy:

    large scale development projects by the government may necessitate compensation and relocation of people to create room for the project. For example the mining of titanium in Kwale has already displaced many people.

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