• 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...

Introduction

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.

Middle

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.

Conclusion

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. 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.

  2. A Local Ecosystem, Patterns in Nature,Life on Earth,The Australian Biota ...

    Food webs often include decomposers. Food chains and food webs are useful for illustrating the trophic interactions that occur between organisms in an ecosystem, but they give no indication of the relative abundance or size of organisms. Food pyramids are models that can take account of how biomass (total mass taking up the organisms in a population)

  1. Yeast Population

    Constant Variable To ensure that the outcomes and occurred only because of the independent variables and not other factors, a set of variables were controlled and kept constant throughout the whole experiment. Amount of Water: It is known that it is important to keep the concentration of yeast and sugar

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

    Some examples of plants that have been proven to be allelopathic are Black Walnut, Tree-Of-Heaven, Broccoli, Eucalyptus and Sunflower plants. In this experiment, the allelopathic plant will be the sunflower plant and the non-allelopathic plant will be the bean plant. The bean plant will be the control in this experiment.

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

    N/A Clear Turbidity � 1 NTU ** 30.00 2.00 3.00 9.00 8.00 Oxygen Levels � 0.01 mg/l 6.45 7.87 7.02 7.00 7.29 pH Level � 0.01 5.50 4.93 6.18 5.27 5.22 ## Salinity � 1 0/00 0.00 0.00 0.00 0.00 0.00 ## Nitrites NO2 � 1 mg/l 0.00 0.00 0.00

  2. How does mowing or not mowing effect the petiole heights of white clover as ...

    The error bars were calculated to show one standard deviation either side of the mean, displaying where 68% of the data lay. My error bars are extremely large. Conclusion and Evaluation Conclusion In my experiment I investigated the effect of mowing on petiole heights of white clover, by sampling petiole heights in unmown and mown areas.

  1. Ecosystem Field Walk

    The bark felt very rough but the leaves were smooth and thin. 4. The tree did not smell very strongly of much but the leaves had a faint scent of campfire. 5. Although I did not notice any, the Eucalyptus tree reproduces through flowering.

  2. (IB) Ecology Observation Report. The tree that Ive chosen to observe from March ...

    This may be explained by the fact that ?X? is coniferous, since conifers maintain green leaves throughout the year. However, some minor changes in ?X? were also visible. I attempted to photograph ?X? from the angle and distance that was closest as possible to the original photograph taken in March (Figure 3).

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