• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Population Ecology - Dandelions

Extracts from this document...


Estimating the size of a dandelion (Taraxacum Officinale) population using quadrat analysis Ashneet Singh 493629 Partners: Harsimar Virdi, Mohak Malik Mr. Crawford September 18, 2009 Purpose To estimate the population of dandelions on the school's football field. Introduction Succession is the process of the development of a sequence of communities over a period of time. There are many methods that are used in ecology to measure the population of a species. Collection of data in the case of immobile (stationary) species, such as the population of plants being studied for this investigation, was collected using line transects. These are analysis methods across a representative part of the habitat, along which quadrats are laid to cover a certain area for collecting population data. The dandelion population being studied is located in the school's soccer field, where some plants have been tempered with, due to mowing and excrements left by another species. Also, human impact (students that play in the fields) has also affected the growth of the population in various places. Variables Controlled - The size of the circular quadrat, meaning the hula-hoop, the day for the experiment, and the distance between each quadrat. Independent - The initial positioning of the quadrat from the base line (first quadrat) ...read more.


The locations with this entity had plants that were smaller than the locations without this entity. Data Processing and Calculations Calculations involving individual data: (Using Table 1) Average Number of Dandelion Plants = = = 20 � 1 dandelion plants/quadrat Area of Quadrat Uncertainty Area of hula-hoop = = ?(0.45 � 0.01m)2 = 0.6362 � 0.0283m2 = (*0.6362 = 0.0283m2 Area of Transect (Football field) Uncertainty = length * width = 75m � 1m * 50m � 1m = 3750 � 125m2 = (*3750 = 125m2 Average Population Density Uncertainty = = = 31.44 2.97 dandelion plants/m2 = (*31 = 2.97 dandelion plants/m2 Estimation of dandelion plant population in the transect Uncertainty = average population density * area of transect = 31.44 2.97 * 3750 125m2 = 117900 15068 dandelion plants/transect = (*117900 = 15068 dandelion plants/transect Calculaitons involving class data (Using Table 2): Table 3: Calculated values for data collected from the class Group number Average Population Density (Dandelion plants/m2) 1 38 3 2 36 3 3 33 3 4 19 2 5 31 3 6 28 3 7 33 3 Estimation of dandelion plant population in the transect (class data) Average Population Density of Class Total Population Size = = = 31.14 2.86 dandelion plants/m2 = Average Population Density of Class * area of transect = 31.14 2.86 * 3750 125 = 116775 14618 ...read more.


Also, since this data was shared within the group, the counting of the population by different members may have created the chance of a differing bias, thus keeping the data inconsistent. The counting of the plant can be difficult due to the way the plant grows in the field, overlapping other dandelion plants. This may also have been the reason to the fluctuations shown in Graph 1, not only due to the excrement and student footsteps in various parts of the field. If this investigation were to be performed again, the steps taken between each successive quadrat should be thoroughly measured with a ruler or tape measure, and then placed, rather than walking 5 steps, which leaves room for huge error. If one wants better representation of data, this is mandatory. When moving towards the fence and away from the base line, one should either look straight ahead and walk in order to stay in the same line transect. Alternatively, the fields could have been marked with lines representing the transects and even the positions of the quadrats, which would have drastically boosted the accuracy and precision of the investigation. Also, if the data is to be shared within the group, then in order to stay consistent, there should be one counter for all the quadrats, removing any discrepancies. These are various ways that the data collection method proves to be very weak and inconsistent. ?? ?? ?? ?? ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. Ecology Open Investigation Does the geographic location affect the biotic and abiotic ...

    Lack of vegetation means less organic detritus. Less vegetation can also be a cause of increase temperature over the years which have affected plant growth. Graph 2.0 also shows immense increase of temperature over the years. In year 2009 the temperature significantly increased compared to the previous years.

  2. Environmental Factors affecting plant growth

    Phosphorus provides the energy required by all organic processes. RNA and DNA are the two nucleic acids components of the genetic information. Most seeds are high in phosphorus; meaning that they already contains phosphorus which helps the plants spend the first few days of its growth period without depending on the soil that it grows in.

  1. Transpiration Investigation

    1156 530 98.3 94.7 96.5 1328 997 1162 540 98.3 94.7 96.5 1338 997 1167 550 98.3 94.6 96.4 1348 979 1164 560 98.2 94.5 96.4 1346 973 1160 570 98.2 94.5 96.3 1339 973 1156 580 98.2 94.4 96.3 1317 959 1138 590 98.1 94.3 96.2 1339 973 1156

  2. Biology Extended Essay 2009

    Due to the lower level of pH of orange juice, makes it more efficient for enzyme inactivation to take place in a shorter time strain. Pasteurized juice normally has a shelf life of 25-40 days.13 Through examining its characteristics, at this stage it is able to be consumed as a substitute to the fresh orange juice.

  1. Allelopathy. Open Investigation Will increasing the number of allelopathic sunflower plants effect the ...

    Factors such as height of plant (mm), size of leaves, number of leaves, colour of leaves and the time it takes the seeds to germinate will be observed and recorded. To and prevent avoid any damage to the plant, daily inspection of bugs and pest will occur.

  2. Biology independent investigation, Ecology

    Many cities and councils in Australia have recently adopted a system in which Na-F will be added into water supplies as it will aid in dental hygiene. This Na-F is existent in trace amount and is very safe for human consumption.

  1. Yeast Population

    the same, as they are the two main factors in this experiment. We will have different results if we did not have constant amounts of water for each. So especially when I was dealing with those two main factors I kept the amount the same, and we used distilled water

  2. Ecosystem Field Walk

    The bee?s scientific name is Apis mellifera. The lady bug?s scientific name is Coccinella magnifica. Keeping in mind that we were in a campus, I felt like there was not a lot of variation or diversity in the plants. There were a lot of trees, mostly eucalyptus.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work