Land
• land is a very important natural resource. It covers 30% of total area of earth’s surface, and all areas are not habitable.
• land is utilised for a variety of areas like agriculture, forestry, mining .
• use of land is based on physical features of land such as topography, soil, climate, minerals & availability of water.
• 90% of world population occupies only 30% of land area and remaining seventy percent of land is either sparsely populated or uninhabited.
• Land is classified on basis of ownership – private land and community land.
• Private land is owned by private individuals whereas, community land is owned by community for common uses.
• Community lands are known as common property resources.
• Limited land and unlimited demand is reason why land conservation is extremely important.
• Afforestation, reclaiming land and minimum use of chemical pesticide and fertilisers are essential to save resource.
• Plains and river valleys offer suitable land for agriculture so these are usually densely populated areas of world.
• Landslides: This is defined as mass movement of rock, debris or soil down a slope. Landslides usually take place in conjunction with earthquakes, floods & volcanoes.
• Mitigation techniques for landslides are:
(1) Mapping of areas prone to landslides.
(2) Increasing vegetation cover to encounter landslides.
(3) Construction of retention wall to stop land from slipping.
Soil
• Soil is thin layer of stuff that covers surface of Earth. shape of land determines type of soil. Only one centimetre of soil is made every hundred years. This is made up of organic matter, minerals, and rocks that have been broken down by weather, and right mix of minerals and organic matter makes it fertile.
• Weathering is defined as breaking up and decay of exposed rocks, by temperature change, frost action, plants, animals & human activity.
• Factors responsible for Soil Formation:
(1) Nature of parent rock
(2) Climatic conditions
(3) Topography
(4) Time
(5) Organic material
Soil Degradation: Major Threats & Factors
• Major Reasons of soil degradation are:
(1) Deforestation
(2) Overgrazing
(3) Excessive use of chemical fertilisers or pesticides
(4) Landslides
(5) Rainwash
(6) Floods
Method to conserve soil
• Mulching: Covering bare ground between plants with a layer of organic matter like straw. Mulching provides moisture to soil.
• Contour barriers: Stones, grass, & soil are used as barrier. Also, trenches are made near barriers to collect water.
• Rock dam: Rocks are placed to slow down flow of water.
• Contour ploughing: Parallel ploughing is done on a hill slope to form a natural barrier for water to flow down slope.
• Terrace farming: Terraces are made on steep slopes to grow crops. It reduces surface runoff and soil erosion.
• Intercropping: Different types of crops are grown in alternate rows and are sown at different times to protect soil from rain water erosion.
• Shelter belts: Generally in coastal and dry regions, rows of trees are planted to check wind movement to protect soil cover.
Water
• Earth is known as water planet and water is one of most important resource.
• Three-fourths of Earth’s surface is covered with water.
• oceans cover two-thirds of Earth’s surface.
• Ocean water is saline and not fit for human consumption.
• Fresh water accounts for only about 2.7% out of which 70% of this occurs as ice sheets and glaciers in Antarctica, Greenland & mountain regions.
• Only 1% of freshwater is available and fit for human use which is found as ground water, or as surface water in rivers and lakes and as water vapour in atmosphere.
• Fresh water is most precious substance on Earth.
• Water can neither be added nor subtracted from Earth. Its total volume remains constant.
Usage
• This is used for agriculture, industries, electricity generation .
• ever increasing population, urbanisation and more demand are a few of main factors that lead to water scarcity.
Problem
• Water shortage is due to variation in seasonal or annual precipitation or scarcity is caused by overexploitation and contamination of water sources.
• Amreli city in Saurashtra region is completely dependent on purchasing water from nearby talukas.
Conservation
• Water harvesting
• Reducing water seepage
• Use of Sprinklers
• Alternative irrigation methods
Natural Vegetation and Wildlife
• Natural vegetation and wildlife exist only in narrow zone of contact between lithosphere, hydrosphere and atmosphere. This narrow zone is called biosphere.
• In biosphere, living beings are inter-related and interdependent on each other for their survival. This life supporting system is known as an ecosystem.
• Wildlife consists of animals, birds, insects . They give us products like milk, meat, wool . Wildlife helps balance ecosystem of Earth.
Distribution of Natural Vegetation
• vegetation growth is mainly due to temperature and moisture.
• major vegetation types are categorised as:
(1) Forests, (2) Grasslands, (3) Scrubs
(4) Tundra
• In heavy rainfall areas, tall trees thrives. In medium rainfall areas, short trees and grasses grow while in low rainfall areas, thorny shrubs are dominant.
Conservation
• National parks
• Wildlife sanctuaries
• Biosphere reserves
• Creeks, lakes & wetlands conservation
• Conducting awareness programmes like social forestry and Vanamohatasava
• National Park: A natural area designated to protect ecological integrity of one or more ecosystems for present and future generations is called a national park.
• Biosphere reserves are a series of protected areas linked through a global network, intended to demonstrate relationship between conservation and development.
Cites
• Convention on International Trade in Endangered Species of Wild Fauna and Flora is an intergovernmental agreement and its purpose is to ensure that international trade of wild animals and plants does not make their survival vulnerable.
• Vultures in Indian subcontinent were dying of kidney failure shortly after scavenging livestock treated with diclofenac.