If you are interested in plant biology then maybe a dissertation on plants and nature could be the best way to go! There are plenty of avenues to explore so if your interests lie within this topic, maybe these examples will help:
Community structure in Australian Ecklonia kelp forests
Physical disturbances such as those initiated by man or by weather such as storms can a long-term effect on community structures in kelp forests. For example, kelp dislodged as a result of severe water turbulence during a cyclone can culminate in the denuding of canopies. Accordingly, sub-species at lower levels can thrive, which in turn may change the nature of the community structure of the forest as a whole. This study not only examines the existing literature on this topic but undertakes an experiment in an Ecklonia radiata kelp forest off the coast of New South Wales. Limited clearing of the canopy was effected and the results observed over a period of time.
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