Evaluation:
Published: 29.11.2003.
Language: English
Level: Secondary school
Literature: n/a
References: Not used
  • Summaries, Notes 'Investigating the Distribution of Streams Invertebrates ', 1.
  • Summaries, Notes 'Investigating the Distribution of Streams Invertebrates ', 2.
  • Summaries, Notes 'Investigating the Distribution of Streams Invertebrates ', 3.
  • Summaries, Notes 'Investigating the Distribution of Streams Invertebrates ', 4.
  • Summaries, Notes 'Investigating the Distribution of Streams Invertebrates ', 5.
Extract

Conclusion
After statistically analysing the critical value of ÷2 (chi- square) that I obtained, which was 113.78, I got to the conclusion that it was much higher than the critical value (3.84). I used 1 degree of freedom to measure the value obtained (÷2 = 113.78) and also the confidence level.
By analysing the value of 1 degree of freedom I became 95% to 99.9% certain that the null hypothesis was incorrect and accepted the alternative hypothesis, which says that there are a higher distribution of chironomus is sandy substrate than in stony substrate, e.g. the number of chironomus per m2 in the sandy region was 97.1 while there was only 5.7 chironomus per m2 in the stony region.
Interpretation
In our investigation I studied Benthic invertebrates, particularly chironomus in the Nant Iago stream in South Wales.
A stream is formed due to gravitational forces that cause an overland flow of water. Many invertebrates live in the streambed creating a Benthic community. …

Atlants