1 .Sand soil • Has course/ large particles • they are larger than those of clay • Loses water quickly • Has less organic matter • Has good aeration • Allows good root penetration • Leaching of nutrients is more in sand soil. • Does not stick when wet 2. Clay soil • Has very fine particles which are closely packed • The soil is sticky when wet and can be moulded into any shape • It holds more water than sand and loam • It has poor drainage • It cracks when dry • It has poor aeration • It does not allow good root penetration 2 .Loam soil • Is a mixture of sand and clay particles • It half clay half sand • It can be easily moulded into a shape but easily crumbles • Holds water for a longer time than sand • It sticks on the hands when wet • It has good drainage • It has good aeration • It allows good root penetration • Loam is the best soil Soil Fertility • When soil has enough plant nutrients it is fertile • Soil fertility is the presence of nutrients in the soil • A farmer can add nutrients to the soil to make it fertile • This is done by applying fertilizers and compost.  • A fertiliser is a substance that is added to the soil to increase fertility • Nutrients found in the soil include Nitrogen, Phosphorus and Potassium ( NPK ) • They are called major nutrients or macro nutrients because they are needed in large quantities   Minor nutrients • Minor nutrients are needed in smaller quantities • Minor nutrients are also called micro nutrients or trace elements • Examples of minor nutrients are boron, iron, zinc, manganese, magnesium and molybdenum Soil erosion • Is the washing away of top soil by agents such as Water Wind Animals Humans 1. Water: • Water washes away soil when it rains. • Loose soil is washed away into dams and rivers. • Steep slopes also lead to soil erosion. • Ploughing 2 . Wind • The blowing away of soil by wind causes soil erosion. • When people cut down trees wind erosion easily takes place. • Type of soil also leads to wind erosion. Which soil type is easily eroded by wind? 3 . Animals • Animal cause soil erosion by overgrazing. • Overgrazing is when animals eat plant or vegetation leaving the ground surface bare. • Animals walking on the same pathway for a long time make the soil loose. • Animals that live underground also burrow loosening the soil. • This makes soil break easily and get washed away. WATER WATER CONSERVATION Water • Water is important in agriculture • It is used to: Clean farm tools Mould bricks Wash milking equipment Cool machines Provide homes(habitat) for fish Give animals drinking and bathing water Sources of Water Natural sources 1. Natural rains: • rain water from the clouds is a primary source of water. • It is used to water crops such as maize, millet, sorghum and so on during the rainy season. • Rain water that collects into the rivers and dams is used by animals and people for drinking. 2 . Rivers : • Rivers are some of the major sources of water for different activities such as fishing, boat cruising and irrigation. 3 . Streams : • A stream is a small river. • Streams supply water for irrigating garden crops especially in rural areas. • They are also a source of water for animals to drink and bath. Sources of Water 4 . Springs : • Springs are usually found on hilly areas. • They result from pressure of underground streams. • The pressure forces water underground to form a channel to the surface of the soil and flow above the ground. Sources of Water Man made sources Man discovered that water for agriculture was not enough during the rain and cool dry seasons. They decided to make structures which would harvest or collect and store water for future use. 1.Protected well: • Wells are dug in the ground by hand. • They are often lined with bricks and concrete so that they do not cave in. • Protected wells are covered, therefore are safe to drink from. 2 . borehole : • They are deep holes made by drilling machines. • Drilling can be done up to 70 metres deep. • Water is pumped using an electric pump or hand pump. Sources of Water 3 . Dams : • A dam is a large wall or barrier built to hold water to save it for future use. 4 . Weir : • A weir is made by construction a cement brick wall or concrete wall across a river to trap water and eroded soil. • water flows over the wall when the river is inflood. 5 .Water tank : • Is a temporary manmade water source. • Water from a water tank is usually harvested from roof tops or it works along a borehole or protected well as temporary storage. • Water is pumped from the borehole or protected well into the water tank. 6 . reservoir : • A large natural or manmade lake used as a source of water. PLANTS Uses of plants • Fibre for making clothes • Oil for cooking, making paint and chemicals • Sugar for tea • Wood for timber • Refreshing drinks and alcohol • Food for people and animals • Protect the soil from erosion • Plants supply us with fresh oxygen for breathing. • Some plant parts are used as medicine.