The document describes two methods for studying plant population density: the quadrant method and the mark-recapture method. The quadrant method involves dividing a study site into 1m x 1m quadrants and counting the number of individuals of different plant species in each quadrant. The density is then calculated as the total number of individuals divided by the total number of quadrants. The mark-recapture method involves trapping and marking a sample of animals, releasing them, trapping again and counting marked and unmarked individuals to estimate the total population size using the Peterson-Lincoln estimator.

1. HAFIZ M WASEEM
LAHORE
PRACTICAL
Study the Plant Population Density by different method (Quadrant and mark
Method)
Aim
Study the plantpopulationdensitybythe quadrantmethod.
Materials Required:
1. Thread
2. Hammer
3. Nails

2. Procedure:
1. Selectasite for the studyand hammerthe nailsonthe site withoutharmingthe vegetation.
2. Fix fournailsinthe form of a square.
3. Each endof the nail istiedwiththe helpof a threadmakinga 1m*1m quadrant.
4. Nine more similarquadrantsare made atthe site of the study.
5. The numberof individualsof the speciesA presentinthe firstquadrantare countedandthe
data isrecordedinthe table.
6. The numberof individualsof speciesA inotherquadrantsis alsocountedandthe data is
recordedinthe table.
7. Similarly,countthe numberof individualsof speciesBandC presentinall the quadrantsand
record the data inthe table.
The densityof the plantpopulationisthencalculatedbythe followingequation:
Density=Total numberof individualsofthe speciesinall samplingunits (S)/Total number of sampling
units studied(Q).
Conclusion
The population density is the highest for species A and the lowest for species C. The density value is
expressed as the number of individuals per unit area.
Mark recaptures method:
Procedure:
1. This technique is used to simulate a population estimated by a wildlife biologist in the
field.
2. The first step is to trap a random sample of animal of the species being studied.
3. These animals are then marked in some manner appropriate to the species and released.
4. In next step do another trapping.
5. Some animals capture d may have been marked from the first sample.
6. Using a simple ratio, a quick population estimate

3. 7. Petersen-lincoln estimator of population size can be made as follows:
N=population estimate
M=number of individuals capture in 1st sample and marked
N=number of individuals captured in second sample.
M=number of n that were already marked
Assuming that marked proportion in the sample is equal to the marked proportion in the
population suggest that
N/M=n/m
To solve for N we rearrange the formula
N=nM/m