sana Archive

NITROGEN CYCLE

The process by which limited amount of nitrogen is circulated and re-circulated throughout the world of living organisms is known as the nitrogen cycle. The chief reservoir of nitrogen is the atmosphere. Nitrogen makes up 78 percent of the gases in atmosphere. Most living

Biogeochemical Cycles

The cyclic exchange of different chemical elements between the living and non-living component of the biosphere is called biogeochemical cycle. Bio means organisms and geo means earth. Movement of chemical elements takes place in back and forth direction in a circular path between organisms

ECOLOGICAL ENERGETIC

The flow of energy through an ecosystem is called ecological energetic. Energy is the ability to do some work. The sun emits light and other types of radiation. Some of these radiations fall on the earth. The light radiation falls on some object. The

ECOSYSTEM

A community with its non-king environment is called ecosystem. Odum, E.P. ( 1959) defines ecosystem as an area of nature, that includes living organism and nonliving substances, interacting to produce an exchange of materials between the living and nonliving parts. Non-living environment provides energy

OBJECTIVE FOR COMMUNITY ECOLOGY

Multiple Choice Questions (MCQS) The plants occurring together with a similar ecology in definite strata are called: (a) Periodicity               (b) stratification(c) Floristic     (d) Vitality The rhythmic phenomena related to seasonal changes is called periodicity. (a) Periodicity               (b) stratification(c) Floristic     (d) Vitality The capacity of

Subjective And Short Questions for Community Ecology

MODEL SUBJECTIVE QUESTION: Give attributes of plant communities. Give physiognomic characteristics. Describe different sampling methods. What is succession? Give its types. Describe different stages of Xerosere. Describe different stages of Hydrosere. Describe different theories of climax. Write note on productivity. Describe local vegetation of

DEFINITIONS AND KEY POINTS FOR COMMUNITY ECOLOGY

TERMS DEFINITIONS   Community The populations of different species living in the same habitat is called community.   Analytic characteristics The   characteristics which  can   be analyzed by Quantitative or   qualitative  methods  are  called analytic characteristics.   Qualitative characteristics The   disruptive  characteristics which  cannot   be

LOCAL VEGETATION OF PAKISTAN

The vegetation in Pakistan is divided into five categories on the basis of climate, altitude and plant types. These are: Dry tropical forest vegetation Dry sub-tropical sub-mountainous vegetation Dry Temperate forests vegetation Moist temperature forest vegetation Sub –Alpine and Alpine vegetation Dry Tropical Forest

CONCEPT OF PRODUCTIVITY

The rate at which food is manufactured by the producers in unit area in unit time is called productivity. There are following types of productivity: Primary Productivity The rate at which solar energy is converted into organic energy by green plants or total food

THEORIES OF SUCCESSION

There are three theories of succession about climax communities: Monoclimax theory This theory was put forward by an American ecologist Frederick Clements in 1916. According to this theory there is only one climax community in a climatic or geographical region. But topographic differences and