C.P. Blacker' demographic transition model

There many demographer and have difference perspective on transition stages. C.P. Blacker has presented five stages of transition phase. These are as follow:

1. High stationary population: This stage is similar to Thomson and Notestein's high potential growth. In a very underdeveloped economy and traditional social system, the difference in the birth and death rates is negligible and therefore the population is almost stationary with irregular fluctuations. Famine and epidemic regularly take heavy tolls on life. He said that 22 percent of world population was at this stage till 1930.
2. Early expansion stage: fulfillment of food supply brought by higher yields in agriculture and better transportation prevent death due to starvation. Frequent famine and epidemic were under some control, medical facilities were extended to common man, preventive medicines put some check on infections diseases, death rate started to fall slowly but birth rate however continues to stay almost at the biological limit. As a result, the population starts to growth. C.P. estimated that 40 percent of world population was at this stage in 1930.

Optimistic view of population

According to follower of these view the inter-dependent of population growth and resources take positive relation and different problem of human society can be solved by using science and technology. Human are not only weight for earth without skill and technology but also can increase capacity and productivity of available sources by using their own knowledge, forethought and skill. People can fulfill their need using multidimensional environmental resources. They believe science and technology is involuntary sources not alternative of natural sources and human society has got many facilities in difference way from science and technological sources. So, it is also called technological optimists thought. Supporter of technological development, believe that human able to solve any problem that is created by human activities. Geologist Martin Lewis expresses his thought on world as one of abundance and opportunity. Follower of these view focuses on only human’ wining on natural resources and pleasure by taking positive development of science and technology’ good events. Progress of technology blindly believe on bringing happiness and prosperous to human society and they do not measure environmental crisis that brings common and publicly from science and technology.

Optimistic view of population

According to follower of these view the inter-dependent of population growth and resources take positive relation and different problem of human society can be solved by using science and technology. Human are not only weight for earth without skill and technology but also can increase capacity and productivity of available sources by using their own knowledge, forethought and skill. People can fulfill their need using multidimensional environmental resources. They believe science and technology is involuntary sources not alternative of natural sources and human society has got many facilities in difference way from science and technological sources. So, it is also called technological optimists thought. Supporter of technological development, believe that human able to solve any problem that is created by human activities. Geologist Martin Lewis expresses his thought on world as one of abundance and opportunity. Follower of these view focuses on only human’ wining on natural resources and pleasure by taking positive development of science and technology’ good events. Progress of technology blindly believe on bringing happiness and prosperous to human society and they do not measure environmental crisis that brings common and publicly from science and technology.

Under Population Region

The term under population refers the less population, weak manpower and weak technology for extreme use of natural resources and services where available natural resources is strong than human manpower. There are more possibilities to increase the life standard and prosperity of community by using adequate available natural resources. But there is no acceptable manpower as natural resources. So there natural resources and services is getting loss without any reason.  Southern world’ evergreen forest of Brazil, Amazon, Congo lays such region. Such world region where could not bring utilization of resources and experience lack of required population for complete utilize of sources. There is found, these types of region distribute and using their own sources from combination, business and support system of over population region. But, there may increase external interference and exploitation so rapidly degrading the natural resources there can be found many result from deforestation and vicious cycle of poverty in Africa and southern America’ countries. Whereas developed countries using their technology for their benefit. There has more or less utility condition of natural resources by the cause of uses of polar region of earth, oceanic region and space for residence because of materialized civilization and human selfish nature.

Over Population Region

The term over population refers the imbalance condition of population and environmental resources where Population is more than environmental resources and services. It is fact that, human need clean and adequate natural resources and service for live. But there is inequality distribution system of population in the world. Somewhere extremely over population has been concentration and uses of resources steps the threshold. Changing population has brought great challenge and decline the life standard.

Pessimistic view of population

Supporter of this view believes environment crisis is brought by growing human’ wasteful uses and highly exploitation of natural resources while fulfilling their need. Many people fight and struggle for few resources to get lower service and need in their life when the world reaches in critical stage because population growth rate increase in geometrical ratio and food in arithmetical ratio. Food is

Balance population and Resources

It has long relation between human and environment. Our living natural and social environment is directly impact by development of technology and progress of science of human activities. So, present pattern of world development, social value, economical system and dynamic demography is moving on from inter-dependent of environment and human population. There are different views about changing sequence occurring on earth by adding mode of social economical development and interrelation between uses of resources, distribution character and changing size of population.

Population Growth and Eco-system

There was ecology stability and warm, nearest and harmonious relation between human and environment for long time with out negative carrying effect of human on environment carrying capacity. But population growth took rapid motion and seriously impact on using ecological services and also some services are ruined that was coming from yore period. Difference environmental

Concept of Eco-system

Generally, Eco-system is called the system of ecology. There is created different unit, organization or spatial on earth interrelation of biological community and their environment that process helps for moving biotic living cycle  continuous in ecology. The level of power and material flows from low to high level in environment. Eco-system refers the functional and structural unit of biological

Concept of Ecology

Ecology is functional structure of natural environment. The word ecology uses as science and providing knowledge about how the biological elements function with natural environment and adopt their structure. Simply, ecology should be understood as study area of why and how cycle taking place between biotic and abiotic element and material in our surrounding environment. Ecology is the

Population Change

There was very slow motion in population growth before 1650 AD in the history of population change. There was estimated about 250 million total population in the world in 1 AD. It took 1650 years to reach 500 million populations in the world. World population reached 1 billion in 1820. In 1930 and in 1975 the world population reached 3 & 4 billion. Population growth rate has seen rapid way so world population can be seen 5 billion in 1987. There are more than 7 billion populations in present world.

Greenhouse effect

Sun light keeps warm atmosphere and earth surface. The worming process is growing day to day by sun light on atmosphere. Greenhouse effect is called the process of warming atmosphere and earth surface by causes of human productive carbon dioxide and Methane gases. Generally, sun light coming process on earth and reflection towards space as radiation move on naturally that makes constant temperature on atmosphere and being warm on earth. But, difference causes product carbon dioxide and Methane gases on atmosphere as green gases these gases block the infrared ray of sun from reflection towards space. That’s way radiation sum as heat atom so greenhouse impact. It is also called global warming.

Sources of Greenhouse Gases

1. carbon dioxide gas is origin from natural gas, oil, coal, as biological flue industrial activities, heating power center and suing vehicle.
2. Chloroform carbon (CFCS) gas is origin from refrigerator, air conditioner, plastic form factory.
3. Methane gas is origin from domestic dirt and garbage.
4. Nitrite oxide gas is origin from increasing and decreasing process of nitrogen atom, forest and grass land conflagration and fire of biological flue.

Global Environment Status

Present global environmental status is moving dynamical process from complex interconnection of difference causes and effects. Rapid population growth, lack of living support goods and resources, raring of flue power, water and air pollution, deterioration of habitation, depletion of natural resources and environment situation is in serious challenge for the present world. Human life style has reached crisis situation. The entire world is in problematic stage from lack of living sources and goods, environment pollution and degradation of natural

Biological Environment

It is moving on action and reaction between biological factors on the surface if earth and made biological layer is called biological environment. Small, big, one cell and multi-cell, aquatic, land and amphibian and million numbers of plants and animals fall in biological environment. Biological world is built from the

Physical Environment

The condition of physical power, natural organic, inorganic and combination of nonliving things is called physical environment. The origin of cause, factor, power and process are also known as physical environment. Solar power, topography-shape, elements, mountain, hill, atmosphere, structure, water cycle, river is known as aspect of physical environment factor. All available elements on earths are aspect of physical environment which helps to create physical and biotic matter. Solar system, radiation, evaporation and sedimentation are the main process of physical environment. Solar power, gravity force and spring changing power build cloud, water, landslide and hill. Above process and factors are known as environmental process. Light, temperature, wind, water, pressure, heat, humidity, topography, slope, land, soil, grow of soil, composition of soil, water cycle, ocean, river are aspect of physical environment.

Water cycle, gases cycle and sedimentation cycle change physical factor into physical and nonphysical factor. These processes develop and manage nutrient store system as result there origin creature.

In perspective of social group, scientific rule and process, natural environment is the strong control power over human activities. Human as well biotic objects can adopt natural environment as their biodiversity capacity and circumstantial condition. Creatures can’t adopt environment, they loss their existence from environment.

      

   

Temperature

Temperature is an important abiotic factor of environment. It is called changing heat (flue) of light. It is constant in differently every objects & animal feature. It is measured Celsius unit. Temperature is changeable factor of environment. So that, its impact fall more on biosphere. Temperature plays an important role for living food, habitation, migration, distribution, fertility, growth, development, coloration and existence of bio-world. Temperature is need according to deference of species’ age and ecological condition. Temperature is important for definite distribution biosphere. Evaporation and elimination process is rapid in high temperature some animal can die in low temperature,

Some of them migrate and some hibernation. Specific structure prepare for plant and animal to live in very low temperature. Such as, leaf falls in winter but plant is alive. Snake, lizard, toad and salamander hide under the land in winter season. Beer, deer and some birds migrate cold to hot place and return their previous inhabit place arrival of spring season.   

Metabolism, reproduction, growth, development, sex ratio, coloration and morphology of plants and animals are determinate by temperature. Temperature impact on sex ratio for example Daphnia small insect give birth only female species in low temperature and both male and female gives birth equally in high temperature. Temperature is an important aspect to exist the environment in own condition.

The wasteful activities of human the level of temperature is growing every year. Deforestation is main cause to increase temperature. When deforestation take place absorb capacity of carbon dioxide is decreased. As result, many problems are seeing on atmosphere, biosphere and other aspects.

 

                                                                                                        

Environmental degradation

Generally, environmental degradation means depletion of quality of environmental factors. Entire biological factors are facing the negative impact of environmental degradation on their daily activities human beings involve depletion activity. Human is main agents for depletion of quality of environmental. They use available environment haphazardly.

In broad meaning, environmental degradation means the negative impact on eco-system or deviation on ecological system. Environmental degradation, environmental depletion, environmental deterioration, environmental damage or environmental pollution is known as the synonym words use for describe depletion of environmental quality. Thus, the negative changing impact on ecological situation and quality is called environmental degradation.

Environmental degradation is overall lowering of environmental qualities and adverse changes brought our buy man in natural resources such and land degradation, deforestation, water quality depletion, air and water pollution and deteriorating quality of human beings. Social problem of ecology is known as the crisis of natural and environmental problem which is origin from human activities. Environmental hazards are those extreme events caused by natural process and human activities that make adjustment difficult property losses and lives.

Environmental degradation process is created by human beings. After that, environmental depletion creates deterioration of human beings and ecological system.

Human in environment

Economic and physical development take place rapid way from initial period of scientific technology develop in 19^th century by the concept of quality life standard. Increasing use of new discovery technology and chemical was developing from 1950 decade. The world’s development activity is being main cause to destroy environment in world widely. Directly or indirectly facing environment problem by human in present world which is created by owns self.

There is green house effect, acid rain, ozone layer depletion, desertification, climate change appearing unreal on biosphere by increasing of uncontrolled urbanization, expansion of dirt and pollution. As well as, rapid forest destruction, soil erosion, flood, land slide, storm, and hazard-able events are increasing and expansion in the present world. Chemical pollution and nuclear pollution is growing dangerously along with rapid development of industries as result entire world’s people commonly facing environment problem which is growing in world. It should understand human also apart organ of environment. Human can’t save their existence beyond natural environment because human also gift of nature. Therefore, human should be conscious while using natural resources and daily livelihood environmental activities.

Own food store cycle is secure when secure while other creatures and plants food cycle secure. No less authority to secure for biosphere creatures and plants on earth. To live equally authority is known as environmental authority.

Human mostly depend on environment so we use natural resources in proper way to mange and use it to save for new coming generation is today’s main duties of world population.

Poverty and environment degradation

Generally, poverty is known as the condition of unable to attempt on access need economics. According to world development report 2010, decreasing of poverty and management of climate change is standing as great challenge for world society. According to latest world population statistical data sheet, there are 2.8 billion people in extreme level of poverty in the world. The report shows the income is less $ 2.  The World Bank present on own report, in south continent countries about 50 percent people are living low standard life.

World Band (2010) there is still 1.2 billion very poor people in developing countries with an annual in come of less than $ 370. Many new babies are born in poor family and struggle to live in poor environment. Poverty is more than lack of income it result from lack of access to health care, education, productive assets and secure livelihood. There are several linkages between poverty and environment. The poor of the world mostly live in the ecologically fragile or sensitive area. They have become both the victims and the agents of environmental degradation.

Thus, the cycle of poverty illness, scarcity and limited opportunities can become a self sustaining process that passes from survival needs and few options, these unfortunate poor people often have no choice to over harvest natural and environmental resources. In doing so, they diminish their own opportunities and also those of future generations.

The demand of food, flue, inhabit place, fulfill services are increased of population growth it all activities directly damage on environment pressure of increasing population create degradation and depletion of natural resources.

  

Population Growth & Environment Degradation

There are estimated about 3 million creatures and plants inhabited on earth. About 50 thousand insects, 2.50 thousand plants, 41 thousand vertebra and remaining invertebrate   creatures and micro species and plants are on earth. There are many plants and creatures are remaining to introduce. These creatures and plants contribute to keep balance between natural environment and eco-system internal and external interaction. Plant makes its food itself and making food other. Dead body of creature buried when it rotten and mix on soil it change into nutrition for plants. This system of interaction is conducting the food changing cycle between creature and plant. The more sue of natural resources increasing day to day population growth along with produce of luxurious goods. The sensible creature is known as human on earth but human only try to hold the environment in hand. Human rapidly use of natural resources’ raw material for industry’s system occurring deviation in natural eco-system. The pressure of artificial environment create dangerous situation towards. Entire creatures, plants and abiotic things’ exist is getting crisis by the irrational activities of human being. Their existence is getting danger by the cause of crisis of rare habitable place which live only depend on nature.

Generally, natural situation is changing in its rule. By this cause to appear new creature and destroy sequence is also moving itself. As result, there is probability to disappear one kind of creature during nine to twelve months. It is known as natural action in its rule. But, there are 48 kinds creatures and plants are raring per day from earth for all situation is moving.  According that raring cycle increasing in biodiversity in coming 3 decade 15 to 50 kinds of creatures are rare from earth for all. It is not natural cause increasing crisis on biodiversity; it is as result of human’s lack of rational behaviors on environment. As result we can’t help to say human existence in danger situation.

Population and Natural Resources

There is created a great problem by the rapid population growth and unequal distribution of population in the world. The relationship between natural resources is differ and province the effect of unequal distribution of world population. According to latest world population data sheet(2010), developed countries carrying below 20 percent world population but there total capacity to access on natural sources more than 80 percent using north developed countries only. The developing countries carrying 80 percent world population but their capacity to access on natural resources below 20 percent. Asian continent is only carrying more than 60 percent world population. But in Australia continent the carrying capacity population ratio is 0.5 percent only. Asian continent’s the high dense population countries China and India carrying 40 percent world population.

The world population growth rate, size and movement unbalance situation is occurring by the effect of war, fighting, division of world. By the all causes, in 1945, the great change came in population growth distribution direction in the history of world population. Israel was born in new country, such Pakistan, Bangladesh countries were divided. African countries took freedom way and moved ahead. Totally, in Asian continent countries create ecological imbalance by increasing dense pressure of population. Adding and increasing awful situation in south Asian continent countries. Such as, Nepal and other developing countries 60 percent people are obligation to live blew poverty line. The population pressure on earth is increasing unacceptably. Population growth directly effect on environment condition. Environment is known as the common house of biotic and abiotic objects. But, the sources of environment is only using sensible creature human in unfavorable way. So that, ecological condition, Eco-system and entire environment situation is getting worse day to day. The highly competition of development is creating worse situation for other important creature. Some of them are losing by unfavorable environment to them. As result, bad situation is occurring on environment.

It should be kept balance between population growth rate and environmental carrying capacity. If human do not do this it can’t say tomorrow human also disappear for all.

Relationship among Population and Environment

Process of human development population, environment and pattern of development process are interrelated each other. Entire social and economical activities of human society are depending on environment resources. World agricultural  production system, production of industry goods, types of human in-habitation, population, natural resources and environmental situation is interrelated each other. Population growth, environment situation and development process should understand reciprocal nature in each other.

Introduction

Introduction

Ecological human population is changing as other biological community. There are many qualitative new approaches and capacity has been developed by change of large size of population. To find out the problem and search new technological tools and using it in the field of solve the population related problems. It has taken great achievement of population growth and expansion. Entire human civilization history has been showing remaining to develop and use of complete human capacity and attitude. Population growth is main cause to adding human related problem, pressure on earth and malpractices. It is not only, the terrorizing condition is occurring by the expansion of rapid population growth but also the process of growth and develops of natural limit reach in sorrow able condition. Every second 3 babies are born and adding 5000 new face in the earth per day. Either these babies born in developed country America or born in developing country in Nepal the adding goods and need amounts are decreasing which is available on earth’s surface. Ecological service, natural source and carrying capacity of earth condition about lead the nature of world population growth. Extreme wrong condition will come on human society in future if the rapid growth rate and trends are checked and to balance between present population growth and environmental condition and natural resources.