Aim-Calculate population density/frequency percentage of plant species by quadrat method.

 Aim-Calculate population density/frequency percentage of ....plant species by quadrat method. 

XII     BIOLOGY  PRACTICAL-7

Q. 3 Calculate population density of ....plant species by quadrat method.

Observation table for density / frequency ……………………….. 2 Marks

Formula for density / frequency.1 Mark

Total -3 Marks

A) Aim:To study population density of plant population by quadrat method.

Requirements: Meter scale, string, nails, paper, pencil, etc.

Procedure:

(1) The population density can be determined by marking quadrats of suitable size. Qua is a square area of vegetation.

(2) With the help of nails and string prepare quadrats of suitable size randomly at a number places.

(3) Count the number of different plant species that are observed in the quadrat.'

(4) Record their numbers in different quadrats viz. Q1, Q2, Q3, Q4, Q5, etc. studied by you.

(5) Record the obtained data in the tabular form given below.

6) Calculate the population density and percentage frequency by the formula given below

Calculation:

Population Density = N/B = 10/5 = 2

Result:Population density of species is =2

B) Aim:To study population frequency percentage of plant population by quadrat method.

Requirements: Meter scale, string, nails, paper, pencil, etc.

Procedure:

(1) The population density can be determined by marking quadrats of suitable size. Qua is a square area of vegetation.

(2) With the help of nails and string prepare quadrats of suitable size randomly at a number places.

(3) Count the number of different plant species that are observed in the quadrat.'

(4) Record their numbers in different quadrats viz. Q1, Q2, Q3, Q4, Q5, etc. studied by you.

(5) Record the obtained data in the tabular form given below.

6) Calculate the population density and percentage frequency by the formula given below

Calculation:

Frequency Percentage = A/B x 100 = 4/5 x 100 = 80 Percentage                     

Result:Frequency Percentage of species  is 80 Percentage

(1) What do you mean by population?

Ans: Organisms of the same kind inhabiting the same geographical area constitute a population.

(2) What is population density? How it can be calculated?

Ans: Population density refers to the number of individuals present per unit spaceat a given time.     It is calculated using the formula -

Population Density =

 

(3) What is a quadrat?

Ans: A quadrat is a frame used in ecology and geography to isolate a standard unit of area to study the distribution of an organism over a large area. It is a sampling unit for study of vegetation.

(4) How is frequency percentage calculated?

Ans: Frequency percentage is calculated by the formula as follows:

(5) How to calculate obundance of plant species? Why should it be calulated in quadrat studies?

Ans: Species abudance is the number of individuals per species. It is expressed as percentage of the total number of species in a community.

 It is calutated by the formula –

(6) What is vegetation?

Ans: Vegetation is total numbers of plant species showing different life forms, structure, spatial extent or showing any other special characteristics, specific to a particular area.