The percentage equitability of richness Essay

The ‘D’ calculated is influenced y two criterion – the percentage equitability of each species and richness. For a certain species richness, the ‘D’ value will lessen as the percentage of the type of organism becomes more equitable. The intertribal zone, as Dry. Gray Williams said, is a very narrow habitat but it is very dynamic,” home to predominantly marine elite where predators include starting, crustaceans and mollusks, and the dynamism is evident in the results collated.

At the high shore, where the surface is dry and hot, and although there is a lower variance of species, the species more abundant at the Geiger shore are evidently suited to dry conditions and many want to avoid the predators that come with the waves. Species distribution on the rocky shores are classified by the species that are strongly influenced by the vertical gradient caused by tides and the horizontal gradient caused by wave action. Species are usually distributed within the tidal range and have upper and lower distribution limits. Space is a limiting resource in the location, sessile species take up much of free rock space.

Certain species, such as Conspiratorial trochees, contrasted significantly tit these findings, and this may be attributed to the features of this species of thin- shelled sea snail; it can breathe air and is therefore found in more abundance on and above the high tide line. The species Plantains calculus, on the other hand, are more often spread in the intertribal zones as indicated by the profusion of such gastropods in the mid-shore area. In the mid-shore zone, there are ten different species present, where in the high-shore there were only seven. This could be due to the nature of the differing species.

This clavier is mostly found in intertribal zones, and we see an habitation anomaly occurring in the Capitulate material, a stalked barnacle generally found in the crevices of lower littoral zones where they can feed on zooplankton, is recorded in abundance in the high-shore. To sum up, although the margin of these diversity indexes is small, there is still evidence to suggest that overall abundance and distribution was higher along the mid-shore transect. This could be due to the aforementioned characteristics of of the intertribal zone and high shore zone along tit the contrasting biotic factors at each shore.

Evaluation There are certain flaws in the design and data collection of this experiment that has led me to determine the following limitations. First and foremost, misidentification of was a major contributor to incongruities in the results. Because of the indistinguishably of certain organisms, whether or not our results are an apt and reliable picture of the diversity of each zone, cannot be comprehended. Another issue with this experiment was human error. The placing of the quadrate in any cases were not consistent and therefore may have skewed the results.

At the high shore the terrain was extremely rocky and crevices and was therefore a more challenging site to count and record the different organisms present. Miscounting of organisms is another aspect of human error that must be addressed. Because many of the species were quite similar in appearance, recounting the same organism was a major issue. In addition, the nature of where the organisms were situated within the quadrate made it extremely difficult to document. Rock crevices at the high shore held many organisms and this limited the accuracy of our results.

To address these limitations, the design and method tot this experiment could b altered in a number of ways. Firstly, increasing the length of the measuring tape to mm or Mm would allow for more results that could be processed in order to come to a more error-free diversity index. Secondly, further training for identifying and distinguishing species prior to the experiment could have aided, for example, key textures, colour and habits of the organisms listed on the table in which we recorded our results could have enabled us to have a better understanding of the organisms and be therefore more likely to correctly record them.

To combat human error, a more careful placement of the quadrate, with another researcher to hold the quadrate in place allowing more concentration on the actual counting and documenting of each type of organism. To avoid recounting the same organism, it can be suggested that organisms that had been counted be moved to a particular area in the quadrate, however this cannot apply for moss and other organisms that cannot be moved.