It occupies nearly 20 percent of the earth surface. It covers around 13000 million hectares of the area. The houses, roads and factories occupy nearly one third of the land. The forests occupy another one third of the land. The rest of land is used for ploughing and for meadows and pastures.
The soil forms the surface layer of land which covers more than the 80 percent of land. The soil is defined as a natural body which keeps on changing and allows the plants to grow. The soil is defined as a natural body which keeps on changing and allows the plants to grow. The branch of science which deals with the formation and distribution of soil in the different parts of the world is referred as a pedology.
Land is used for different purposes like agriculture, forestry, mining, building houses, roads and setting up of industries. Land use is the human use of land. Land use involves the management and modification of natural environment or wilderness into built environment such as fields, pastures, and settlements
Land use practices vary considerably across the world. It has also been defined as the arrangements, activities and inputs people undertake in a certain land cover type to produce, change or maintain it. This is known as land use.
By educating, informing and sensitizing all landholders about various aspects of this precious resources and their sustainable use. Contour ploughing is another measure to conserve our land. By this method, the fields are ploughed, harrowed and sown along the natural contour of the hills. By terracing method: A series of wide steps are made along the slop following the contours. This method is very common in rice growing regions.
Under the afforestation and reforestation programmes, planting of trees, bushes and grass help to check the soil erosion. Strict actions are taken to check reckless felling of trees and overgrazing. Shelter belts (rows of trees) are planted on the margins of desert areas to check the fury of wind. Construction of dams and gully-trap inculcate the water-harvesting.
Soil is a natural body consisting of layers (soil horizons) of primarily mineral constituents, which differ from their parent materials in their texture, structure, consistency, color, chemical, biological and other physical characteristics. Soil is composed of particles of broken rock that have been altered by chemical and mechanical processes that include weathering, erosion and precipitation.
Soil forms a structure that is filled with pore spaces, and can be thought of as a mixture of solids, water and air (gas). On a volume basis a good quality soil is one that is 45% minerals (sand, silt, clay), 25% water, 25% air, and 5% organic material, both live and dead. Little of the soil of planet Earth is older than the Tertiary and most no older than the Pleistocene.
Factors responsible for soil formation are :-1. Parent material2. Climate3. Living organisms4. Topography5. Time
The relative influence of each factor varies from place to place, but the combination of all five factors normally determines the kind of soil developing in any given place. We used a model of soil organic matter (SOM) quantity and composition to simulate steady- state organic matter levels for 24 grassland locations in the Great Plains.
Soil degradation is when soil deteriorates because of human activity and loses its quality and productivity. Soil degradation is when soil deteriorates because of human activity and loses its quality and productivity. It also happens when the soil structure breaks down, or if the soil becomes toxic from pollution.
The primary cause of soil degradation is erosion, but compaction, salinization, and depletion by nutrient demanding crops may also cause degradation. Soil degradation is which the movement of soil particles from one place to another by wind or water, is considered to be a major environmental problem.
Certain conservation measures can reduce soil erosion.1. Agronomic: such as plant / soil cover, conservation farming methods, contour farming.2. Vegetative: such as planting barriers (vegetative strips), live fences, windbreaks.3. Structural: such as Fanya Juus, terraces, banks , bunds, cut off drains, barriers.4. Overall management: such as area closures, selective clearing.
Soil management practices such as tillage and cropping practices, directly affect the overall soil erosion problem and solutions on a farm. When crop rotations or changing tillage practices are not enough to control erosion on a field, a combination of measures might be necessary.
Mulching:- The bare ground between plants is covered with a layer of organic matter like straw. Contour barriers:- Stone, grass, soil are used to build barriers to collect water along contours. Trenches are made in front of the barriers to collect water. Rock clam:- Rocks are piled up to slow down the flow of water. This prevents gullies and further soil loss.
Terrace farming:- Board flat steps or terraces are made on the steep slopes so that flat surfaces are available to grow crops. Intercropping:- Different crops are grown in alternate rows and are sown at different times to protect the soil from rain wash.
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state.
Water covers 70.9% of the Earths surface, and is vital for all known forms of life. On Earth, 96.5% of the planets water is found in oceans, 1.7% in groundwater, 1.7% in glaciers and the ice caps of Antarctica and Greenland, a small fraction in other large water bodies, and 0.001% in the air as vapor, clouds and precipitation. Only 2.5% of the Earths water is freshwater, and 98.8% of that water is in ice and groundwater. Less than 0.3% of all freshwater is in rivers, lakes, and the atmosphere, and an even smaller amount of the Earths freshwater (0.003%) is contained within biological bodies and manufactured products
There is a scarcity of water in many regions of the world. Most of Africa, West Asia, South Asia, parts of Western USA, north-west Mexico, parts of South America and entire Australia are facing shortages in fresh water supply. Countries located in climatic zones most susceptible to droughts face great problems of water scarcity.
Water conservation refers to reducing the usage of water and recycling of waste water for different purposes such as cleaning, manufacturing, and agricultural irrigation. Water should be conserved to meet our daily needs and future use.
Methods for conserving water resources :-1. By using water properly and giving it time to get renewed.2. By using sprinkler system.3. By using drip irrigation system.4. By creating awareness.
Natural vegetation and animal life depend on climate, relief and soil. The diversity of India’s climate and relief have made natural vegetation and animal life interdependent on each other and they form a single ecosystem. This ecosystem has evolved through thousands of years.
India has a wide variety of natural vegetation ranging from tropical evergreen forests to desert vegetation. The natural vegetation of India can be divided into six main types. They are : -1. Tropical evergreen forests.2. Tropical deciduous forests or Monsoon forests.3. Tropical thorn and shrub forests.4. Desert vegetation.5. Mangrove forests.6. Himalayan vegetation.
TROPICAL EVERGREEN FORESTS This type of vegetation is found in areas where rainfall is above 250 cms and temperature ranges between 250C and 270C. Since the trees are always green they are called evergreen forests. The heavy rainfall, high temperature and humidity are responsible for the growth of these dense forests. The trees grow about 60 mts. Ebony, mahogany, rose-wood and rubber are the important trees. Bamboo bushes are also found.
These forests are also called monsoon forests. They cover a greater part of India. They are found in regions where the rainfall is between 75cms and 250 cms. These forests are found on the eastern slopes of the Western Ghats, Jammu, West Bengal, Chhattisgarh, Orissa, Bihar and Jharkhand. In these forests, the trees are fewer and shorter. The important trees of these forests are teak, sal and sandal- wood. The deciduous forests of Karnataka have sandal-wood trees. Wherever these forests are cut down or burnt, bushes and grass have taken their place.
These forests are found in the central parts of the Deccan Plateau, southern parts of Maharashtra, Bellary of Karnataka, Cuddapha and Kurnool of Andhra Pradesh, where the annual rainfall is between 60 and 75 cms. These forests have short stemmed trees like Babul and Kasavi trees and coarse grass. Palms and kikar trees are also found here.
This type of vegetation is found in regions where the annual rainfall is less than 50 cms. Rajasthans Thar desert, the borders of Punjab, Haryana and Gujarat have this type of vegetation. The trees, which grow here have deep roots, thick leaves and thorns. Date palms are common near oasis. Babul, palms, wild dates and cactus are the important trees. Babul tree yields gum and its bark yields tanning material.
These forests are formed due to tides. They are found along the deltas and estuaries of rivers that are subjected to tides. Pendent roots (like those of Banyan tree) are the characteristics of mangrove forests. The deltas of rivers Ganges, Godavari, Mahanadi and Krishna have these forests. In the Ganges delta, there are plenty of Sundari trees and the forests are known as ‘Sunderbans’. These trees are used for making furniture and boats. Canes, palms and "Kendale" trees are also found here.
Different types of vegetation are found in the Himalayan mountains. The vegetation changes with altitude and rainfall. The lower regions of the Himalayas have tropical evergreen forests up to 1,500 mts. Teak, sal and rose-wood are the important trees. They are also called coniferous forests.