Question

1. What are the limits of the biosphere? What factors would limit the distribution of plants? What factors would limit the distribution of animals?

2. What are the components of an ecosystem? Detail the flow of energy in a food chain.

3. How do the concepts of habitat and niche overlap? How do they differ? Give examples.

4. It is clear that the greenhouse effect caused by rising levels of CO2 will have many dire consequences in agriculture. Would there be any benefits to plants from higher CO2 levels in the atmosphere?

5. List examples of primary and secondary succession and trace the transitional stages in each type of succession.

6. List and describe the major biomes found on the North American continent. Climbing up a mountain, the vegetational zones encountered are similar to the biomes passed on a journey north. Why? What is the altitudinal effect on temperature and precipitation?

7. Make a list of rain forest products obtained by extractive reserves available in local stores.

Answer 1

The sum of all ecosystems of a region where all kinds of life forms exist is known as biosphere. Ecosystem supports all life forms since it contains the three basic component necessary for survival of any organism i.e; land(lithosphere), water(hydrosphere) and air(atmosphere) are found in right amount.

the biosphere, and the living conditions of all organisms are

closely related to natural aqueous solutions. The matter of

organisms is formed principally of aqueous salt solutions: Pro-

toplasm may be considered an aqueous suspension in which

coagulations and colloidal changes occur. The phenomena of

ionization are ubiquitous. Because of continuous, reciprocal

action between the internal liquids of the organisms and the

surrounding aqueous solutions, the relative ionizations of the

two media are of great importance. Subtle methods of recording

exact changes in ionization provide an excellent way to study

the principal medium of life.

Sea water contains about 10-9% (H+); it is thus slightlyalka-

line, and is continuously maintained so, in the presence of

numerous ongoing chemical processes.

This degree of ionization is very favorable for the life of

marine organisms; the slightest variations always have repercus-

sions in living nature, positive or negative, depending on the

organism.

It is clear that life can exist only within limits of ionization

between 10-6 and 10-1°% (H + ).249

110 The physical state of the medium is extremely important for

life processes. Life in latent form can be preserved in solid, liq-

uid, or gaseous states, and in a vacuum. Seeds can be preserved

for a certain time, without gaseous exchange, in all states of mat-

ter. But the fully-functioning living organism requires gaseous

exchange (respiration), and stable conditions for the colloidal

systems that form its body. In solid media, living organisms are

found only in porous bodies where there is access to gaseous

exchange. Due to the very small dimensions of many organisms,

fairly compact media can be inhabited; but a liquid solution or

colloid cannot maintain life if it lacks gas.

We once again encounter the exceptional importance of the

gaseous state of matter, a point frequently made in this essay.

The Limits of Life in the Biosphere

111 Thus far, we have seen that the biosphere, by structure, com-

position, and physical makeup, is completely enclosed by the

domain of life, which has so adapted itself to biospheric condi-

tions that there is no place in which it is unable to manifest itself

in one way or another.

This statement does not hold true under temporary, abnormal

circumstances, such as would prevail during times of eruptingvolcanoes and lava flows. Toxic volcanic exhalations

(hydrochloric and hydrofluoric acids, for example), and hot

springs which accompany volcanic action, are examples of such

temporary phenomena; the absence of life caused by them is

also temporary. Analogous phenomena of longer duration, such

as permanent thermal sources with temperatures of about 90°

C, are inhabited by organisms adapted to these conditions.

Natural saline solutions with concentrations more than 5%

may not be permanently inanimate; we simply do not know

whether they are or not. The Dead Sea in Palestine is regarded as

the largest saltwater basin of its kind. There is proof, however,

that certain naturally acidic waters (containing hydrochloric

and sulfuric acid), whose ionization is at least 10-11% (H+), must

be inanimate250 (§109). The extent of such dead zone is, howev-

er, insignificant when compared to the planet as a whole.

112 The terrestrial envelope occupied by living matter, which

can be regarded as the entire field of existence of life, is a con-

tinuous envelope, and should be differentiated from discontin-

uous envelopes such as the hydrosphere.

The field vital stability is, of course, far from completely occu-

pied by living matter; we can see that a slow penetration of life

into new regions has occurred during geological time.

Two regions of the field of vital stability must be distin-

guished: 1. the region of temporary penetration, where organ-

isms are not subject to sudden annihilation; and 2. the region of

stable existence of life, where multiplication can occur.

The extreme limits of life in the biosphere probably represent

absolute conditions for all organisms. These limits are reached

when anyone of these conditions, which can be expressed as

independent variables of equilibrium, becomes insurmountable

for living matter; it might be temperature, chemical composi-

tion, ionization of the medium, or the wavelength of radiations.

Definitions of this kind are not absolute, since adaptation

gives organisms immense ability to protect themselves against

harmful environmental conditions. The limits of adaptation are

unknown, but are increasing with time on a planetary scale.

Establishing such limits on the basis of known adaptations of

life requires guesswork, always a hazardous and uncertain

undertaking. Man, in particular, being endowed with under-

standing and the ability to direct his will, can reach places that

are inaccessible to any other living organisms.251

Given the indissoluble unity of all living beings, an insight

A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources. Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource. For example, if there are not enough prey animals in a forest to feed a large population of predators, then food becomes a limiting factor. Likewise, if there is not enough space in a pond for a large number of fish, then space becomes a limiting factor. There can be many different limiting factors at work in a single habitat, and the same limiting factors can affect the populations of both plant and animal species. Ultimately, limiting factors determine a habitat's carrying capacity, which is the maximum size of the population it can support.

Limiting Factors

That's the Limit

In the natural world, limiting factors like the availability of food, water, shelter and space can change animal and plant populations. Other limiting factors, like competition for resources, predation and disease can also impact populations. If any of the limiting factors change, animal and plant populations change, too.

Some changes may cause a population to increase. If there are more plants than usual in an area, populations of animals that eat that plant may increase. If one animal's population increases, the population of animals that eats that animal might also increase.

Increases in population aren't always good. Sometimes a population will grow too large for the environment to support. Other changes in limiting factors will cause a population to decrease. If a population becomes diseased, the population may decrease and the population of animals that eat the diseased animals will also decrease.

In nature, populations usually balance themselves. Sometimes when man impacts populations, they can't always reestablish a natural balance.

Human Factors

Humans can impact animal and plant populations. When humans develop land for houses and buildings, they cut down trees and change animal and plant habitats. Some animals like the raccoon and the skunk can adapt, but other animals can't adapt and their populations are affected.

The common loon nests on land near large lakes. Some loon nesting places have been taken over by human development and the loon population has decreased. Pollution can also hurt animal and plant populations. Sometimes hunting can impact animal populations. Whale populations have been lowered because of overhunting.

Natural Balance

Predator/prey relationships play a big role in animal populations. If the balance between predator and prey is changed, populations are changed. The white-tailed deer population in some areas has grown too large because there are no natural predators. Mountain lions and wolves are the natural predators of the white-tailed deer. Wolf and mountain lion populations have been lowered due to overhunting and habitat loss. This loss of a natural predator for the white-tailed deer, along with other factors, has led to overpopulation of the white-tailed deer in some areas.

Components of Ecosystem

There are two main components of an ecosystem which are in constant communication with each other. They are the biotic components and the abiotic components.

Biotic Components of Ecosystem

The living components of an ecosystem are called the biotic components. Some of these factors include plants, animals, as well as fungi and bacteria. These biotic components can be further classified, based on the energy requirement source. Producers, consumers, and decomposers are the three broad categories of biotic components.

Producers are the plants in the ecosystem, which can generate their own energy requirement through photosynthesis, in the presence of sunlight and chlorophyll. All other living beings are dependent on plants for their energy requirement of food as well as oxygen.

Consumers include herbivores, carnivores, and omnivores. The herbivores are the living organisms that feed on plants. Carnivores eat other living organisms. Omnivores are animals that can eat both plant and animal tissue.

Decomposers are the fungi and bacteria, which are the saprophytes. They feed on the decaying organic matter and convert this matter into nitrogen and carbon dioxide. The saprophytes play a vital role in recycling the nutrients so that the producers i.e. plants can use them once again.

(Source: Encyclopedia-Britannica)

Abiotic Components of Ecosystem

Abiotic components are the physical and/or the chemical factors that act on the living organisms at any part of their life. These are also called as the ecological factors. The physical and chemical factors are characteristic of the environment. Light, air, soil, and nutrients, etc. form the abiotic components of an ecosystem.

The abiotic factors vary from ecosystem to ecosystem. In an aquatic ecosystem, the abiotic factors may include water pH, sunlight, turbidity, water depth, salinity, available nutrients and dissolved oxygen. Similarly, abiotic factors in terrestrial ecosystems can include soil, soil types, temperature, rain, altitude, wind, nutrients, sunlight etc.

Here, the sun is the energy source. Producers/plants use this energy to synthesize food in the presence of carbon dioxide and chlorophyll. The energy from the sun, through several chemical reactions, turns into chemical energy.Difference Between Habitat and Niche

May 20, 2017 By Rachna C 1 Comment

Habitat is a set of the place of environmental conditions in which particular organism lives and adapt the situation accordingly. A niche is nothing but an idea or role played by organisms that how they can live in an environment including their diet, shelter, etc. Mainly niche is concerned with the factor of gaining energy by organisms and supplying it to other, in the ecosystem.

A habitat defines the interaction of organisms with the other factors, which can be living or non-living, while niche describes how that specific organism is linked with its physical and biological environment.

Habitat is the part of the ecosystem, while niche plays an important role in the formation of an ecosystem. Both the words describe the living habits of the organisms of all kinds of species, how they interact with each other, what do they eat, their shelter, etc. Each organism plays their particular role in its ecosystem and also have their own defined niche in the ecosystem.

Ecology is the study of all the living beings and their interactions with the environment, whether a plant or an animal or other organisms. It also includes non-living things such as temperature, soil, water, rocks, climate, etc.

The above-described terms are the part of ecosystem only, and they are very closely related, having a thin layer of difference, which is mark full though. In the given content we will discuss the general and the key difference between both of them.

Content: Habitat Vs Niche

Comparison Chart

Definition

Key Differences

Conclusion

Comparison Chart

BASIS FOR COMPARISON HABITAT NICHE

Meaning A habitat is an area, where a species lives and interact with the other factors. A niche is an ideology, of how an organisms lives or survive in the provided environmental conditions.

Consist of Habitat consist of numerous niches. Niches does not contains such components.

It includes Affect of temperature, rainfall and other abiotic factors. Flow of energy from one organisms to other through ecosystem.

Examples Desrets, oceans, forest, rivers, mountains, etc. are examples of habitat. It is a part of habitat only, where shelter for living being can be furnished.

Supports Habitat supports numerous species at a time. Niche supports a single species at a time.

What it is Superset Subset

Nature Habitat is a physical place. Niche is an activity performed by organisms.

Specificity Habitat is not species specific. Niche is species specific.

Definition of Habitat

Place or area where a particular species lives is its habitat. A habitat is a part and is considered as the real place of an ecosystem. Factors like the sunlight, average rainfall, annual temperatures, type of soil present and other abiotic factors may affect the presence of organisms and traits in that environment. These factors help in determining the presence of the particular type of species suited for that environment.

We can say that habitat is a nutrient or energy providing area for all types of organisms, irrespective of the kinds of species. Habitat defines as a field where all living organisms live in the natural environment and reflect their way of living.

Pond, river, ocean is the best example of habitat as many organisms are found in the same place or habitat. These habitats can be arboreal, terrestrial, aerial, aquatic, etc.

Definition of Niche

The term niche was first time used by ‘Grinnell’ in 1971. The term ecological niche is still not well understood and is sometimes even misused. Niche is nothing but an idea of the distributional unit, where organisms are kept within their constitutional and instigative boundations.

Niche can be further described as appearance and post of a species in the environment; like what they do for their survival, how they fulfill their needs of shelter, food, etc. So it is used to describe as where an organism lives. In short, we can say that niche is not a place but it is