Our environment has been providing us with a variety of goods and services necessary for our day to day lives since our existence. A resource is something that humans need and value. It can be things such as land, air, and water. Resources are characterized as renewable or non-renewable; a renewable resource can replenish itself at the rate it is used, while a non-renewable resource has a limited supply. Renewable resources include timber, wind, and solar while non-renewable resources include coal and natural gas. These natural resources available in the environment include air, water, soil, minerals, along with the climate and solar energy, which form the non-living or ‘abiotic’ part of nature. The ‘biotic’ or living parts of nature are comprised of plants and animals, including microbes. Plants and animals can only survive as groups of different organisms, who are all closely linked to each other in their habitat. Thus, forests, grasslands, deserts, mountains, rivers, lakes, and the marine environment all form habitats for specialized groups of plants and animals to live in. Interactions between the abiotic aspects of nature and some specific living organisms together form ecosystems of various types. Many of these living organisms are used as our food resources. Others are linked to our food in a less direct way, such as pollinators and dispersers of plants, animals in the soil like worms, which recycle nutrients for the growth of plants, and fungi and termites that break up dead plant material so that micro-organisms can act on them to reform soil nutrients.
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Biotic and abiotic aspects of nature
History of our global environment: About ten thousand years ago, when mankind changed from a hunter-gatherer, living in wilderness areas such as forests and grasslands, into an agriculturalist and pastoralist, we started to change the environment for our requirements. As our ability to grow food and use domestic animals improved, the existing ‘natural’ ecosystems were developed into agricultural lands. Most traditional agriculturists depended largely on rain, streams, and rivers for water supply. Later on, the use of wells to tap underground water sources and to utilize water began. The land was irrigated by building dams. Recently, we began to use fertilizers and pesticides to further increase the production of food from the same land. However, we now realize that all this has led to several undesirable changes in our environment. Mankind has been overusing and depleting natural resources. The extensive usage of land has been found as a reason for exhausting the capability of the ecosystem to support the growing demands of more and more people. Industrial growth, urbanization, population growth, and the enormous increase in the use of consumer goods, have all put further stresses on the environment. They create great quantities of solid waste. Pollution of air, water, and soil has begun to seriously affect human health.
- Non-Renewable resources
Non-renewable resources consist of fossil fuels such as oil and coal, which if extracted at the present rate, will soon be consumed. The end products of fossil fuels are in the form of heat and mechanical energy and chemical compounds, which cannot be reconstituted as a resource. Non-renewable resources, once used, remain on earth in a different form and, unless recycled, become waste material.
- Renewable resources
Even though water and biological living resources might be considered renewable, they are, in fact, renewable only within certain limits. They are linked to natural cycles such as the water cycle. Freshwater is evaporated by the sun’s energy which forms water vapor and is reformed into clouds which later fall on earth as rain. However, water sources can be overused or wasted to such an extent that they locally run dry. Water sources can be so heavily polluted by sewage and toxic substances that it becomes impossible to use the water. Forests once destroyed take thousands of years to regrow into fully developed natural ecosystems with their full complement of species. Forests can, thus, be said to behave like non-renewable resources if they are overused. Fish are today being over-harvested until the catch has become a fraction of the original resource and the fish are incapable of breeding successfully to replenish the population. The output of agricultural land if mismanaged drops drastically. When the population of a species of plant or animal is reduced by human activities, until it cannot reproduce fast enough to maintain a viable number, the species becomes extinct. Many species are probably becoming extinct without us even knowing about their existence and other linked species are also affected by their loss.
Key Takeaways:
1) Resources are essential for the survival of humans.
2) Resources can be classified as renewable and non-renewable.
3) Mankind has caused undesirable changes in the environment by overusing the resources causing their depletion.
Resources can be divided into various groups such as:
a) Forest resources
b) Water resources
c) Mineral resources
d) Food resources
e) Energy resources
f) Land resources
We will study each of these resources in brief.
The resources on which mankind is dependent are provided by various sources or ‘Spheres’. The Atmosphere provides oxygen for human respiration (metabolic requirements), oxygen for wild fauna in natural ecosystems and domestic animals used by man as food, oxygen as a part of carbon dioxide, used for the growth of plants. The atmosphere forms a sort of protective shield over the earth.
The stratosphere is 50 kilometres thick and contains a layer of sulphates which is important for the formation of rain. It contains a layer of ozone that absorbs ultra-violet light known to cause cancer. Without the ozone layer, no life could exist on earth. The sun does not warm the atmosphere uniformly. This leads to air flows and variations in climate, temperature, and rainfall in different parts of the earth. It is a complex dynamic system. If its nature is disrupted it affects all
The Hydrosphere provides clean water for drinking (a metabolic requirement for living processes), water for washing and cooking, water used in agriculture and industry, food resources from the sea, including fish, crustacea, seaweed, etc., food from freshwater sources, including fish and aquatic plants, water flowing down from mountain ranges harnessed to generate electricity in hydroelectric projects. The hydrosphere covers three-quarters of the earth’s surface. A major part of the hydrosphere is the marine ecosystem in the ocean, while only a small part occurs in freshwater.
The Lithosphere is responsible for soil, which is the basis for agriculture to provide us with food. It also includes stone, sand, and gravel, used for construction, micronutrients in the soil which are essential for plant growth, microscopic flora, small soil fauna and fungi in the soil, important living organisms that break down plant litter as well as animal wastes to provide nutrients for plants. It is comprised of a large number of minerals on which our industries are based such as oil, coal, and gas, extracted from underground sources. It provides power for vehicles, agricultural machinery, industry, and our homes.
The Biosphere is responsible for the food from crops and domestic animals, providing human metabolic requirements. Along with food, it fulfills the energy needs by providing biomass fuelwood collected from forests and plantations, other forms of organic matter used as a source of energy, Timber, and other construction materials. This is the thin layer on the earth in which life can exist and thrive. Within it, the air, water, rocks, and soil, and the living creatures, form structural and functional ecological units, which together can be considered as one giant global living system, that of our Earth itself
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Spheres of earth
a) Forest resources
Use and overexploitation: Scientists estimate that India should ideally have 33 percent of its land under forests. Today we have only about 12 percent. Thus, there is not only the need to protect existing forests but also to increase our forest cover. People who live in forests or nearby, know the value of forest resources because their lives and livelihoods depend directly on these readily available resources. However, the rest of the people also derive great benefits from forests which we might not be aware of. The water we use depends on the existence of forests and the watersheds around river valleys. Our homes, furniture, and paper are made from wood from the forest. We make use of many medicines that are based on forest produces. And we depend on the oxygen that plants give out and also on the removal of carbon dioxide we breathe out in the air. People have used forests in our country for thousands of years. As agriculture spread, the forests were cleared or left in patches that were controlled mostly by the tribal people. They hunted animals and gathered plants and lived entirely on forest resources. Deforestation became a major concern when a large amount of timber was extracted for building ships. This led to a great loss in the forest cover and gradual degradation of forests.
Forest functions.
Watershed protection:
• Reduce the rate of surface run-off of water.
• Prevent flash floods and soil erosion.
• Produces prolonged gradual run-off and thus prevents effects of drought. Atmospheric regulation:
• Absorption of solar heat during evapotranspiration.
• Maintaining carbon dioxide levels for plant growth.
• Maintaining the local climatic conditions.
Erosion control:
• Holding soil (by preventing rain from directly washing soil away).
Landbank:
• Maintenance of soil nutrients and structure.
Local use - Consumption of forest produce by local people who collect it for subsistence – (Consumptive use)
• Food - gathering plants, fishing, hunting from the forest.
• Fodder - for cattle.
• Fuelwood and charcoal for cooking, heating.
• Poles - building homes especially in rural and wilderness areas.
• Timber – household articles and construction.
• Fibre – the weaving of baskets, ropes, nets, string, etc.
• Sericulture – for silk.
• Apiculture – production of bees for honey, forest bees also pollinate crops.
• Medicinal plants - traditionally used medicines, investigating them as a potential source for new modern drugs.
Market use - (Productive use)
• Most of the products used for consumptive purposes are also sold as they serve as a source of income for supporting the livelihoods of forest-dwelling people.
• Minor forest produce - (non-wood products): Fuelwood, fruit, gum, fiber, etc. which are collected and sold in local markets as a source of income for forest dwellers.
• Major timber extraction - construction, industrial uses, paper pulp, etc. Timber extraction is done in India by the Forest Department, but illegal logging continues in many of the forests of India and the world.
Deforestation is the practice of permanent removal of trees to make room for something besides the forest. This can include clearing the land for agriculture or grazing or using the timber for fuel, construction, or manufacturing. The places where civilizations have looked after their forests by using forest resources cautiously, they have prospered; whereas the places where the forests were destroyed, the people gradually impoverished. Today, logging and mining are serious causes of the loss of forests. Dams that were built for hydroelectric power or irrigation submerged the forests and have now displaced the tribal people whose lives depended on the forests.
Forests cover more than 30% of the Earth's land surface, according to the World Wildlife Fund. These areas can be the source of provision of food, medicine, and fuel for more than a billion people. Today, most deforestation takes place in the tropics. Areas, where access couldn’t be gained in the past, are now within reach as new roads are constructed through dense forests.
Often, deforestation occurs when a forested area is cut and cleared to make way for agriculture or grazing. Deforestation in tropical regions can affect the way water vapor is produced over the canopy, which causes reduced rainfall. A study published in the journal of Ecohydrology in 2019 showed that some parts of the Amazon rainforest were converted to agricultural land. These parts had higher soil and air temperatures, which can intensify drought conditions. In comparison, forested land had rates of evapotranspiration that were almost three times higher, which helped in adding more water vapor to the air.
Trees absorb carbon dioxide, thus removing greenhouse gas emissions produced by human activity. Deforestation, along with removing vegetation that is important for the removal of carbon dioxide from the air, also produces greenhouse gas emissions themselves. Deforestation accounts for nearly 20% of greenhouse gas emissions.
Developing alternatives to deforestation can help decrease the need for tree clearing. For example, the desire to expand the amount of land used for agriculture is an attractive reason to deforest an area. But if people tried adopting sustainable farming practices or implemented new farming technologies on crops, the need for more land might be diminished. Forests can also be restored, through replanting trees in cleared areas or simply allowing the forest ecosystem to regenerate over time. The goal of restoration is to return the forest to its original state, before it was cleared, the sooner a cleared area is reforested, the quicker the ecosystem can start to repair itself. Gradually, wildlife may return, water systems might get re-established, carbon will be sequestered and soils will be replenished.
Key takeaways:
1) Resources can be classified into various types such as forest resources, water resources, food resources, mineral resources, energy, and land resources.
2) Some of the major benefits that we enjoy are derived from forest resources such as the provision of oxygen, water, furniture, fuelwood, gum, fruits, and fodder, etc
3) Forest cover has reduced tremendously over years due to deforestation. Carbon dioxide absorption by trees gets affected due to deforestation. Deforestation is the cause of almost 20% of the greenhouse gas emissions.
b) Water resources
The water cycle, through evaporation and precipitation, maintains hydrological systems that form rivers and lakes and support a variety of aquatic ecosystems. Wetlands are intermediate forms between the land and aquatic ecosystems and they consist of species of plants and animals that are highly dependent on moisture. All aquatic ecosystems are utilized by a large number of people for their daily activities such as drinking water, washing, cooking, watering animals, and irrigating fields. The world depends on a limited quantity of freshwater. Water covers 70% of the earth’s surface but only 3% of this is freshwater. One of the greatest challenges faced by the world in this century is the need to manage water resources. The world population has passed the 6 billion mark. Based on the number of young people in developing countries, the population will continue to increase significantly during the next few decades. This places enormous demands on the world’s limited fresh water supply. The total annual freshwater withdrawals today are estimated at 3800 cubic kilometres, twice as much as just 50 years ago (World Commission on Dams, 2000). Studies suggest that a normal person needs a minimum of 20 to 40 liters of water per day for drinking and sanitation. More than one billion people worldwide have no access to clean water, and to many more, supplies are unreliable. Examples are Ethiopia, which is upstream on the Nile, and Egypt, which is downstream and highly dependent on the Nile. International accords that will look at a fair distribution of water in such areas will become critical to world peace. India and Bangladesh have made a negotiation agreement on the water use of the Ganges.
Overutilization and pollution of surface and groundwater: With the growth of the human population there is an increasing need for larger amounts of water to fulfil a variety of basic needs. At this point, in many areas of the world, this requirement cannot be met. Overutilization of water occurs at various levels. Most people use more water than they need. Most of us waste a lot of water during a bath by using a shower or during washing of clothes. Many agriculturists use more water than necessary to grow crops. There are ways in which farmers can try to use less water without reducing yields like using the drip irrigation technique. Agriculture also pollutes surface water and underground water stores by the excessive use of chemical fertilizers and pesticides. Methods such as the use of biomass as a fertilizer and non-toxic pesticides such as neem products and using integrated pest management systems reduce the agricultural pollution of surface and groundwater. The industry tends to maximize short-term economic gains by not bothering about its liquid waste and releasing it into streams, rivers, and the sea. In the longer term, as people become more conscious of using ‘green products’ made by eco-sensitive industries, the polluter’s products may not be used. The industry causing pollution which does not care for the environment and pays off bribes to get away from the cost needed to use effluent treatment plants may eventually be caught, punished, and even closed down. Public awareness may increasingly put pressure on the industry to produce only eco-friendly products which are already gaining in popularity. As people begin to learn about the serious health hazards caused by pesticides in their food, public awareness can begin putting pressure on farmers to reduce the use of chemicals that are injurious to health.
Global climate change: Changes in climate at a global level caused by increasing air pollution have now begun to affect our climate. In some regions across the world, global warming has created unprecedented effects. In other areas, it has led to long droughts. Everywhere the ‘greenhouse effect’ due to atmospheric pollution is leading to increasingly erratic and unpredictable climatic effects. This has seriously affected regional hydrological conditions.
Drought: In most arid regions of the world the rains cannot be predicted. This leads to periods when there is a serious scarcity of water to drink, use in farms, or provide for urban and industrial use. Drought prone areas are thus faced with irregular periods of famine. Agriculturists have no income in the years of scarcity, and as they have no steady income, they have a constant fear of droughts. While it is not entirely possible to prevent the failure of the monsoon, good environmental management can reduce its ill effects. The scarcity of water during drought years affects households, agriculture, and industry. It also leads to food shortages and malnutrition which especially affects children largely. Several measures can be taken to minimize the serious impacts of drought. However, this must be done as a preventive measure so that if the monsoons fail its impact on local people’s lives is minimized. In the time when the monsoon is adequate, we use up the ample supply of water without trying to conserve it and use the water judiciously. Thus, during a year when the rains are scarce, there is no water even for drinking in the drought area. Deforestation is one of the factors that worsen the effect of drought. Once hill slopes are cleared of forest cover, the rainwater rushes down the rivers and is lost. Forest cover permits water to percolate in the area permitting it to seep into the ground. This increases the underground stores of water level in natural aquifers. This can be used in the time when drought hits if the stores have been filled during a good monsoon. If water from the underground storage is overused, the level of water table reduces and vegetation suffers. Soil and water management and afforestation are long-term measures that reduce the impact of droughts.
Sustainable water management: ‘Save water’ campaigns are very important to make people aware of the dangers of water scarcity. Several measures need to be taken for the better management of the world’s water resources. These include measures such as:
• Building numerous small reservoirs instead of few mega projects.
• Develop small catchment dams and protect wetlands.
• Soil management, micro catchment development, and afforestation permits the recharging of underground aquifers thus reducing the need for large dams.
• Treating and recycling municipal wastewater for agricultural use.
• Preventing leakages from dams and canals.
• Preventing loss in Municipal pipes.
• Effective rainwater harvesting in urban environments.
• Water conservation measures in agriculture such as using drip irrigation.
• Pricing water at its real value makes people use it more responsibly and efficiently and reduces the wastage of water.
In deforested areas where land has been degraded, soil management by bunding along the hill slopes and making ‘Nala’ plugs, can help retain moisture and make it possible to re-vegetate degraded areas. Managing a river system is best done by leaving its course as undisturbed as possible. Dams and canals lead to major floods in the monsoon and the drainage of wetlands seriously affects areas that get flooded when there is high rainfall.
Dams: As of today, there are more than 45,000 large dams around the world, which play a very important role in communities and economies that harness these water resources for their economic development. The world’s two most populous countries – China and India – have built around 57% of the world’s large dams.
Dams problems
• Fragmentation and physical transformation of rivers.
• Serious impacts on riverine ecosystems.
• The social consequences of large dams caused due to displacement of people.
• Waterlogging and salinization of surrounding lands.
• Dislodging animal populations, damaging their habitat, and cutting off their migration routes.
• Fishing and travel by boat disrupted.
• The emission of green-house gases from reservoirs which occur due to rotting vegetation and carbon inflows from the catchment is a recently identified impact.
Large dams have had serious impacts on the lives, livelihoods, cultures, and the existence of indigenous and tribal peoples. They have suffered disproportionately from the negative impacts of dams and have often been excluded from sharing the benefits. Conflicts over dams have heightened in the last two decades because of their social and environmental impacts and failure to achieve targets for sticking to their costs as well as achieving promised benefits. Recent examples show how failure to provide a transparent process that includes effective participation of local people has prevented affected people from playing an active role in debating the pros and cons of the project and its alternatives. The loss of traditional, local controls over equitable distribution remains a major source of conflict.
Key Takeaways:
1) Many species of plants and animals are dependent on the aquatic ecosystem. Humans need water for the purpose such as drinking, washing, agriculture, etc.
2) Overutilization and pollution of water resources have resulted in the depletion of surface and groundwater. The use of pesticides and fertilizers can pollute water resources.
3) Global warming and the greenhouse effect have resulted in droughts and floods.
4) Dams are used to harness water resources for our utility. Large dams have given rise to problems like Fragmentation of rivers, waterlogging, dislodging of animals and humans, disruption in fishing, etc.
c) Mineral Resources
A mineral can be defined as a naturally occurring substance of definite chemical composition and identifiable physical properties. An ore is a mineral or combination of minerals from which a useful substance, such as a metal, can be extracted and used to manufacture a useful product. Minerals were formed for millions of years in the earth’s crust. Iron, aluminium, zinc, manganese, and copper are important raw materials for industrial use. Important non-metal resources include coal, salt, clay, cement, and silica. The stone which is used for building material, such as granite, marble, limestone, constitute another category of minerals. Minerals with special properties that man values for their aesthetic and ornamental value are gems such as diamonds, emeralds, rubies. The lustre of gold, silver, and platinum is used for ornaments. Minerals in the form of oil, gas, and coal were formed when ancient plants and animals were converted into underground fossil fuels. Minerals and their ores need to be extracted from the earth’s interior so that they can be used. This process is known as mining. Mining operations generally go through four stages:
(1) Prospecting: Searching for minerals.
(2) Exploration: Assessment of the size, shape, location, and economic value of the deposit.
(3) Development: The task of preparing access to the deposit so that the minerals can be extracted from the site.
(4) Exploitation: Extracting the minerals from the mines. In the past, mineral deposits were discovered by prospectors in areas where mineral deposits the exposure on the surface in minute forms
Today, however, the prospecting and exploration process are done by teams of geologists, mining engineers, geophysicists, and geochemists who work together to discover new deposits. Modern prospecting methods include the use of sophisticated instruments like GIS to survey and study the geology of the area. The technique to being adopted for mining has to be determined depending on whether the ore or mineral deposit is near to the surface or deep within the earth. The topography of the region and the physical nature of the ore deposit is deeply studied. Mines are of two types – surface (open cut or strip mines) or deep or shaft mines. Coal, metals, and non-metalliferous minerals are all mined using different methods depending on various criteria. The method to be chosen for mining will ultimately depend on how the maximum yield may be obtained under existing conditions by incurring a minimum cost and with the least danger to the mining personnel. Most minerals require processing before they become usable. Thus ‘technology’ is dependent on both the presence of resources and the energy necessary to make them ‘usable’.
Mine safety: Mining is a very hazardous occupation, and the safety of mine workers is an important environmental consideration of the industry. Surface mining is less hazardous as compared to underground mining. Metal mining is less hazardous than coal mining. In underground mines, falling of rocks and roof, flooding, and inadequate ventilation are the greatest hazards. Large explosions have occurred in coal mines, killing many miners. Many miners suffer from disasters due to the use of explosives in metal mines. Mining poses several long-term occupational hazards to the miners. Dust produced during mining operations is injurious to health and causes a lung disease known as black lung or pneumoconiosis. Fumes generated by incomplete dynamite explosions are extremely poisonous. Methane gas, emitted from coal strata, is a health hazard although not poisonous in the concentrations usually encountered in mine air. Radiation is a hazard in uranium mines.
Key Takeaways:
1) Minerals in the form of oil, gas, and coal were formed when ancient plants and animals were converted into underground fossil fuels.
2) Important non-metal resources include coal, salt, clay, cement, and silica. The stone which is used for building material, such as granite, marble, limestone, constitute another category of minerals.
3) Mining of resources takes place in four stages namely, prospecting, exploration, development, exploitation.
4) Mining is a very hazardous occupation and can cause many diseases or may result in death. Mining has also resulted in the degradation of the lithosphere, hence, harming the environment.
d) Food resources
Today our food is sourced almost entirely from agriculture, animal husbandry, and fishing. Although India is self-sufficient in food production, it is only because of modern patterns of agriculture that are unsustainable and which pollute our environment with excessive use of fertilizers and pesticides. The Food and Agriculture Organisation (FAO) defines sustainable agriculture as that which conserves land, water, and plant and animal genetic resources does not degrade the environment and is economically viable and socially acceptable. Most of the large farms grow single crops (monoculture). If this crop is hit by a pest, the entire crop can be devastated, leaving the farmer with no income during the year. On the other hand, if the farmer uses traditional varieties and grows several different crops, the chance of complete failure is lowered considerably. Many studies have shown that one can use alternatives to inorganic fertilizers and pesticides. This is known as Integrated Crop Management.
• Our fertile soils are being exploited faster than they can recuperate.
• Forests, grasslands, and wetlands have been converted to agricultural use, which has led to serious ecological questions.
• Our fish resources, both marine, and inland, show evidence of exhaustion.
• There are great disparities in the availability of nutritious food. Some communities such as tribal people still face serious food problems leading to malnutrition, especially among women and children.
These issues bring in new questions as to how demands will be met in the future even with a slowing of population growth. Today the world is seeing a changing trend in dietary habits. As living standards keep on improving, people are eating more non-vegetarian food. As people shift from eating grain to meat, the world’s demand for feed for livestock based on agriculture increases as well. This requires more land per unit of food produced and this results in the world’s poor not getting enough to eat.
Women play a very vital role in food production as well as cooking the meal and in feeding children. In most rural communities they have the least exposure to technical training and health workers trained in teaching/learning on issues related to nutritional aspects. Women and girls frequently receive less food than men. These disparities need to be corrected.
In India, there is a shortage of cultivable productive land. Thus, farm sizes are too small to support a family on farm produce alone. With each generation, farms are being subdivided further Poor environmental agricultural practices such as slash and burn, shifting cultivation, or ‘rabi’ (wood-ash) cultivation degrade forests.
Globally 5 to 7 million hectares of farmland are degraded each year. Loss of nutrients due to overuse of agricultural chemicals are major factors in land degradation. Water scarcity is an important aspect of poor agricultural outputs. Salinization and waterlogging have affected a large amount of agricultural land worldwide.
Loss of genetic diversity in crop plants is another issue that is leading to a fall in agricultural production. Rice, wheat, and corn are the staple foods of almost two-thirds of the world’s population. As wild relatives of crop plants in the world’s grasslands, wetlands, and other natural habitats are being lost, the ability to enhance traits that are resistant to diseases, salinity, etc. is lost. Genetic engineering is an untried and risky alternative to traditional cross-breeding.
Food Security: It has been estimated that almost 18 million people worldwide, most of whom are children, die every year due to starvation or malnutrition, and many others suffer from a variety of dietary deficiencies.
The earth can only supply a limited amount of food. If the world’s carrying capacity to produce food cannot meet the needs of a growing population, anarchy and conflict will follow. Thus, food security is closely linked with population control through the family welfare program. It is also linked to the availability of water for farming. Food security is only possible if food is equally distributed to all. Many of us waste a large amount of food. This eventually places great stress on our environmental resources. A major concern is the support that is needed for small farmers so that they remain farmers. If not, they have to shift to urban centres as unskilled industrial workers. International trade policies concerning an improved flow of food across national borders from those who have surplus to those who have a deficit in the developing world is an issue that is of great concern for planners who deal with international trade concerns.
Fisheries: Fish is an important protein food in many parts of the world. This includes marine and freshwater fish. While the supply of food from fisheries increased phenomenally between 1950 and 1990, in several parts of the world fish catch has since dropped due to overfishing. Modern fishing technologies use mechanized trawlers and small meshed nets which lead directly to overexploitation, which is not at all sustainable. It is quite evident that fish have to breed successfully and need to have time to grow if the yield has to be used sustainably. The small traditional fishermen are the worst -hit who are no match for organized trawlers.
Loss of Genetic diversity: There are 50,000 known edible plants documented worldwide. Of these, only 15 varieties produce 90% of the world’s food. Modern agricultural practices have resulted in a grave loss of the genetic variety of crops. A cereal that has multiple varieties growing in different locations does not permit the rapid spread of disease.
The most effective method to introduce desirable traits into crops is by using characteristics found in the wild relatives of crop plants. As the wilderness shrinks, these varieties are rapidly disappearing. Once they are lost, their desirable characteristics cannot be introduced when found necessary in the future. To ensure long-term food security, conserving wild relatives of crop plants in National Parks and Wildlife Sanctuaries is required.
If plant genetic losses worldwide are not slowed down, some estimates show that as many as 60,000 plant species, which accounts for 25% of the world’s total, will be lost by the year 2025. The most economical and effective way to prevent this is by expanding the network and coverage of our protected Areas. Collections in germplasm, seed banks, and tissue culture facilities, are other possible ways to prevent extinction but are extremely expensive.
Scientists believe that the world will soon need a second green revolution to meet our future demands of food which should be based on a new ethic of land and water management that includes environmental sensitivity, equity, biodiversity conservation of cultivars, and in-situ preservation of wild relatives of crop plants. This might not only be able to provide food for all but also work out in favor of more equitable distribution of both food and water, reduce agricultural dependence on the use of fertilizers and pesticides (which have long term ill effects on human wellbeing), and provide increased support for preserving wild relatives of crop plants in Protected Areas. Pollution of water sources, land degradation, and desertification must be rapidly reversed. Adopting soil conservation measures, using appropriate farming techniques, especially on hill slopes, enhancing the soil with organic matter, rotating crops, and managing watersheds at the micro-level are a key to agricultural production to meet future needs. Most importantly, food supply is closely linked to the effectiveness of population control programs worldwide. The world needs better and sustainable methods of food production which is an important aspect of land use management.
Key Takeaways:
1) Food is mainly sourced through agriculture, animal husbandry, and fishing.
2) However, due to increased demand, fertile soils are exploited, forests are converted into agricultural land and fish resources show exhaustion. The shift from grain to meat has also resulted in increased demand for life-stock.
3) Food security is closely linked to population control. Equal distribution of food is necessary to prevent conflict, anarchy, and starvation.
4) Plant genetic losses need to be slowed down. A new ethic of land that is based on environmental sensibility, equity, biodiversity conservation, and preservation of wild relatives of farm crops is to be adopted.
e) Energy Resources
The sun is the primary energy source in our lives almost everywhere in the world. We use it directly for its warmth and through various natural processes that provide us with food, water, fuel, and shelter. The sun’s rays are responsible for the growth of plants, which form our food material, provide oxygen which we breathe in, and take up carbon dioxide that we breathe out. Energy from the sun evaporates water from oceans, rivers, and lakes, to form clouds that turn into rain. Today’s fossil fuels were once the forests that grew in prehistoric times due to the energy of the sun.
Chemical energy, contained in chemical compounds is released when they are broken down by animals in the presence of oxygen. In India, manual labor is still extensively used to get work done in agricultural systems, and domestic animals used to pull carts and plows. Electrical energy can be produced in several ways. The energy can come from hydel power based on the water cycle that is powered by the sun’s energy that supports evaporation, or from thermal power stations powered by fossil fuels. Nuclear energy is held in the nucleus of an atom and is now harnessed to develop electrical energy.
We use energy for household use, agriculture, production of industrial goods, and for running transport. Modern agriculture uses chemical fertilizers, which consumes large amounts of energy during their manufacture. Industry uses energy to power manufacturing units and the urban complexes that support it. Energy-demanding roads and railway lines are built to transport products from place to place and to reach raw materials in mines and forests.
No energy-related technology is completely ‘risk-free’ and unlimited demands on energy increase this risk factor many folds. Using any type of energy creates heat and contributes to increasing atmospheric temperature. Many forms of energy release carbon dioxide which leads to global warming. Nuclear energy plants cause enormous losses to the environment due to the leakage of nuclear material. The inability to effectively manage and safely dispose of nuclear waste is a serious global concern.
At present, almost 2 billion people worldwide have no access to electricity at all. While more people will require electrical energy, those who do have access to it continue to increase their requirements. Also, a large proportion of energy from electricity is wasted during transmission as well as at the user level. It is broadly accepted that long-term trends in energy use should be towards a cleaner global energy system that is less carbon-intensive and less reliant on finite non-renewable energy sources. It is estimated that the currently used methods of using renewable energy and non-renewable fossil fuel sources together will be insufficient to meet foreseeable global demands for power generation beyond the next 50 to 100 years.
Thus, when we use energy wastefully, we are contributing to a major environmental disaster for our earth. We all need to become responsible energy users.
Growing energy needs: Energy has always been closely linked to man’s economic growth and development. Present strategies for development that have focused on rapid economic growth have used energy utilization as an index of economic development. This index, however, does not take into account the long-term ill effects on society of excessive energy utilization. The world’s demand for electricity has doubled over the last 22 years. Electricity is at present the fastest growing form of end-use energy worldwide. Although coal continues to remain the major fuel for electricity generation, nuclear power has been increasingly used since the 1970s and 1980s and the use of natural gas has increased rapidly in the 80s and 90s.
Non-Renewable Energy Sources: These consist of the mineral-based hydrocarbon fuels coal, oil, and natural gas, that were formed from ancient prehistoric forests. They are known as ‘fossil fuels’ because they are formed after life is fossilized. At the present rate at which extraction is done, there is enough coal for a long time to come. Oil and gas resources however are likely to be used up within the next 50 years. When these fuels are burnt, they produce waste products that are released into the atmosphere as gases such as carbon dioxide, oxides of sulphur, nitrogen, and carbon monoxide, all causes of air pollution. These have led to lung problems in an enormous number of people all over the world and killed many forests and lakes due to acid rain. Many of these gases also act like a green-house letting sunlight in and trapping the heat inside. This is leading to global warming, a rise in global temperature, increased drought in some areas, floods in other regions, the melting of icecaps, and a rise in sea levels, which is slowly submerging coastal belts all over the world. Warming the seas also leads to the death of sensitive organisms such as coral.
Oil and its environmental impacts: Most of our natural gas is linked to oil and, because there is no distribution system, it is just burnt off. This wastes nearly 40% of available gas. The processes of oil and natural gas drilling, processing, transportation, and their utilization have serious environmental consequences. For Ex. leaks in which air and water are polluted and accidental fires that may go on burning for days or weeks before the fire can be controlled. During refining oil, solid waste such as salts and grease are produced which also damages the environment. Oil slicks are caused at sea from offshore oil wells, cleaning of oil tankers, and shipwrecks. The most well-known disaster occurred when Oil-powered vehicles emit carbon dioxide, sulfur dioxide, nitrous oxide, carbon monoxide, and particulate matter which is a major cause of air pollution especially in cities with heavy traffic density. Leaded petrol leads to neuro damage and reduces attention spans.
Coal and its environmental impacts: Coal is the world’s single largest contributor of greenhouse gases and is one of the most important causes of global warming. Many coal-based Power generation plants are not fitted with devices such as electrostatic precipitators which are to be used for the reduction of emissions of suspended particulate matter (SPM) which is a major contributor to air pollution. Burning coal also produces oxides of sulphur and nitrogen which when combined with water vapor may lead to ‘acid rain’. This results in the death of forest vegetation, and it also damages architectural heritage sites, pollutes water, and affects human health. Thermal power stations that use coal produce waste in the form of ‘fly ash’. Large dumps are required to dispose of this waste material. Some efforts have been made to use fly ash for making bricks. The transportation of large quantities of fly ash and its eventual dumping costs are the costs incurred which have to be included in calculating the cost-benefits of thermal power.
Renewable energy: Renewable energy systems use resources that are constantly replaced and are usually less polluting. Examples include hydropower, the solar, wind, and geothermal (energy from the heat inside the earth). We also get renewable energy from burning trees and garbage as fuel and processing other plants into biofuels. One day, all our homes may get their energy from the sun or the wind. Your car’s gas tank will use biofuel. Your garbage might contribute to your city’s energy supply. Renewable energy technologies will improve the efficiency and cost of energy systems. We may reach the point when we may no longer rely mostly on fossil fuel energy.
Some major sources of energy are:
- Hydro-electric power.
- Solar energy.
- Photovoltaic energy.
- Solar-Thermal electric power.
- Biomass energy.
- Biogas.
- Tidal and wave power.
- Geothermal energy.
- Nuclear energy.
Energy Conservation:
It is easy to waste energy but cheaper to save it than to generate it. We can conserve energy by preventing or reducing waste of energy and by using resources more efficiently. People waste energy because the government subsidizes it. If the real cost was levied, people would not be able to afford to waste it.
Key Takeaways:
1) Sun is our primary resource of energy. We use energy for household use, agriculture, production of industrial goods, and for running transport. No energy-related technology is completely ‘risk-free’ and unlimited demands on energy increase this risk factor many folds.
2) There are three main types of energy; non-renewable; renewable; and nuclear energy, which uses such small quantities of raw material (uranium) that supplies are to all effect, limitless.
3) Non-renewable resources consist of the mineral-based hydrocarbon fuels coal, oil, and natural gas, that were formed from ancient prehistoric forests. They are known as ‘fossil fuels’ because they are formed after life is fossilized such as coal. Coal is the world’s single largest contributor of greenhouse gases and is one of the most important causes of global warming.
4) Renewable energy systems use resources that are constantly replaced and are usually less polluting. Examples include hydropower, the solar, wind, and geothermal (energy from the heat inside the earth). We also get renewable energy from burning trees and garbage as fuel and processing other plants into biofuels.
f) Land resources:
Land on earth is as finite as any of our other natural resources. While mankind has learned to adapt his lifestyle to various ecosystems the world over, he cannot live comfortably for instance on polar ice caps, under the sea, or in space in the foreseeable future.
Man needs land for building homes, cultivating food, maintaining pastures for domestic animals, developing industries to provide goods, and supporting the industry by creating towns and cities. Equally importantly, man needs to protect wilderness areas in forests, grasslands, wetlands, mountains, coasts, etc. to protect our vitally valuable biodiversity. Thus, rational use of land needs careful planning.
Land Degradation: Farmland is under threat due to extensive utilization. Every year, between 5 to 7 million hectares of land worldwide is added to the existing degraded farmland. When soil is used by farming extensively, it is eroded more rapidly by wind and rain. Over irrigating farmland leads to salinization, as evaporation of water brings the salts to the surface of the soil on which crops cannot grow. Over irrigation also creates waterlogging of the topsoil so that crop roots are affected and the crop deteriorates. The use of more and more chemical fertilizers poisons the soil so that eventually the land becomes unproductive.
Soil erosion: The characteristics of natural ecosystems such as forests and grasslands depend on the type of soil. Soils of various types support a wide variety of crops. The misuse of an ecosystem leads to the loss of valuable soil through erosion by the monsoon rains and, to a smaller extent, by the wind. The roots of the trees in the forest hold the soil. Deforestation thus leads to rapid soil erosion. Soil is washed into streams and is transported into rivers and finally lost to the sea. The process is more evident in areas where deforestation has led to erosion on steep hill slopes as in the Himalayas and in the Western Ghats. These areas are called ‘ecologically sensitive areas’ or ESAs. To prevent the loss of millions of tons of valuable soil every year, it is essential to preserve what remains of our natural forest cover. It is equally important to reforest denuded areas. The linkage between the existence of forests and the presence of soil is greater than the forest’s physical soil binding.
Key Takeaways:
1) Landforms such as hills, valleys, plains, river basins, and wetlands include different resource generating areas that the people living in them are dependent on.
2) The land is also converted into a non-renewable resource when highly toxic industrial and nuclear wastes are dumped on it.
3) Farmland is under threat due to extensive utilization. As urban centers grow and industrial expansion occurs, the agricultural land and forests shrink.
4) The misuse of an ecosystem leads to the loss of valuable soil through erosion by the monsoon rains and, to a smaller extent, by the wind. To prevent the loss of millions of tons of valuable soil every year, it is essential to preserve what remains of our natural forest cover.
Until fairly recently mankind acted as if he could go on forever exploiting the ecosystems and natural resources such as soil, water, forests, and grasslands on the Earth’s surface and extracting minerals and fossil fuels from underground. But, in the last few decades, it has become increasingly evident that the global ecosystem can sustain only a limited level of utilization. Biological systems cannot go on replenishing resources if they are overused or misused. At a critical point, increasing pressure destabilizes their natural balance. Even biological resources traditionally classified as ‘renewable’ - such as those from our oceans, forests, grasslands, and wetlands, are being degraded by overuse and may be permanently destroyed. And no natural resource is limitless. ‘Non-renewable’ resources will be rapidly exhausted if we continue to use them as intensively as at present.
The two most damaging factors leading to the current rapid depletion of all forms of natural resources are increasing ‘consumerism’ on the part of the affluent sections of society, and rapid population growth. Both factors are the results of the choices we make as individuals. As individuals we need to decide;
• What will we leave to our children? (Are we thinking of short-term or long-term gain?)
• Is my material gain someone else’s loss?
Greed for material goods has become a way of life for a majority of people in the developed world. Population growth and the resulting shortage of resources most severely affects people in developing countries. In nations such as ours, which are both developing rapidly, and suffering from a population explosion, both factors are responsible for environmental degradation. We must ask ourselves if perhaps reached a critical flashpoint, at which economic ‘development’ affects the lives of people more adversely than the benefits it provides.
What can you do to save electricity?
• Turn off lights and fans as soon as you leave the room.
• Use tube lights and energy-efficient bulbs that save energy rather than bulbs. A 40 W tube light gives as much light as a 100 W bulb.
• Keep the bulbs and tubes clean. Dust on tubes and bulbs decreases lighting levels by 20 to 30 percent.
• Switch off the television or radio as soon as the program of interest is over.
• A pressure cooker can save up to 75 percent of the energy required for cooking. It is also faster.
• Keeping the vessel covered with a lid during cooking, helps to cook faster, thus saving energy.
References :
- Textbook Of Environmental Science By Deeksha Dave And E.Sai Baba Reddy, Cengage
- Publications.
- Text Book Of Environmental Sciences And Technology By M.Anji Reddy, Bs Publication.
- Comprehensive Environmental Studies By J.P.Sharma, Laxmi Publications.
- Environmental Sciences And Engineering – J. Glynn Henry And Gary W. Heinke – Prentice Hall Of
- India Private Limited.
- A Text Book Of Environmental Studies By G.R.Chatwal, Himalaya Publishing House
