Study the plant population density by quadrate method

Experiment No.                                 Date:

Aim of the experiment: To study the plant population density by quadrate method in Namrup College campus

Principle: The number of individuals of a species present per unit area of a given time is called population density. It is the ratio between the total number of individuals of a certain species and the total number of quadrates studied. Quadrat represents field area of appropriate size (50cm x 50cm, 1m x 1m for herbaceous vegetation).

Population density (D) is calculated by counting total number of individuals of the species present at a given time in a given area divided by the number of units of area (quadrat)

Population density = Total number of individuals of a species in all the quadrats studied (N)/Total number of quadrats studied (B)

Requirements: Square of 50cm x 50cm or 100cm x 100cm size, paper, pencil, preserving materials (hard board with papers fit)

Procedure: A 50 cm × 50 cm quadrat was placed randomly within the herbaceous vegetated area of the Namrup College campus. The plants of each species found in each quadrat were counted and recorded. In total, ten quadrats of identical size were laid at random in the study area, and the plant species present in them were identified. Unknown herbaceous species were collected and preserved for later identification with the guidance of the teacher. The total count of each species from all quadrats was then recorded separately.

Observation and calculation:

After the field observation, data are tabulated as follows and calculated the density as per the formula.

Sl. Nos.	Name of the plant species	Quadrate wise number of species recorded during the study										Total nos. of a individual species in all the quadrats studied (N)	Total nos. of quadrats studied (B)	Population density D=N/B
		Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Q9	Q10
1	A	2	3	-	-	2	-	-	-	-	3	10	10	1.0
2	B	4	-	3	4	1	-	2	3	-	-	17	10	1.7
3	C	-	-	5	3	-	2	2	3	-	2	17	10	1.7
4	D	-	-	-	4	-	1	3	1	-	-	9	10	0.9
5	E	-	-	-	-	6	-	-	3	1	-	10	10	1
6	F	-	-	-	-	-	5	4	1	2	-	12	10	1.2
7	G	-	-	-	-	-	-	3	1	2	1	7	10	0.7
8	H	-	-	-	-	-	-	-	5	5	4	14	10	1.4
9	I	-	-	-	-	-	-	-	-	5	2	7	10	0.7
10	J	-	-	-	-	-	-	-	-	-	2	2	10	0.2

Result: From the field study, a total of 10 species of herbaceous plants were collected from the Namrup College campus. The names of the species are, A, B, C, D, E, F, G, H, I and J

Inference: From the present study it is found that density of species B and C is highest, whereas, density of species J is lowest in the college campus.

Precautions:

1. Pre-determined quadrat size or area should be measured appropriately,

2. Quadrats laid down or marked area in one field should not be very far from each other,

3. Quadrat should not overlap each other,

4. Number of plant species should be carefully counted,

5. Attention should be taken that all species encountered inside the quadrat must be recorded,

6. Proper safety measure should taken from leech, snake or other wild animals

 [Students must write actual species name and number in place of species given in the table]