Marine Ecosystem

Oceanography courses often require research papers on marine ecosystems. Paper Masters will custom write research on any aspect of marine ecosystems you need explored.

The manner in which plants defend themselves reflects the nature of the threats which they face and the defense systems of plants native to fresh water differ in a number of ways from those found in marine plants. Whilst external deterrents such as thorns may be effective to a limited degree, this marine ecosystem research paper will concentrate on the chemical defenses evolved in order to defeat the efforts of herbivore attackers. Within a marine ecosystem, the individual plants have a range of molecules which are able to evolve, over many generations, a range of biochemical weapons to prevent predation. This is not, however, always as effective as the anti-predation measures taken by terrestrial plants.

The portieria hornamannii or red alga, can, like all sea-dwelling algae, produce metabolites to prevent herbivore predation, but these have only a limited effect against fish and, in the case of some predators, notably the Aplysia Parvula or sea hare, the production of the metabolite ochtodene may be seen to have the opposite effect to the desired deterrent, with the sea hare having evolved a system of incorporating the metabolite into its system and thriving. The sea hare is known to graze on the red alga and the metabolite is thought to actually stimulate feeding in the sea hare. This arrangement appears to work only with this host/ predator pairing, and the metabolites are more effective against other prey, but, as the red alga provides not only important nutrients but also physical protection for the sea hare, it can be seen that it has somehow evolved a method of rendering safe the otherwise toxic metabolites, in order to continue its association with the alga. There is some benefit in this pairing for the alga too, as the attentions of the sea hare seem to limit feeding on the alga by other predators.

The concept of the ecosystem, a biological community together with the abiotic environment in which it lives, forms the foundation for a specific branch of ecology termed ecosystems ecology. More than just a mere study of the ways in which environmental changes affect our personal and global systems, this particular branch delves into the ways in which organisms interact with the biotic and abiotic components of their surroundings and the ways energy is transferred among each one. While the most basic of its roots lie in the work completed by botanists several hundred years ago, in more recent years five men have made significant contributions to this field. Through their work, a variety of physiological processes and ideas were identified, such as the transfer of energy among producers, consumers, and decomposers as proposed by Lindeman and based upon groundbreaking work conducted by Tansley; Clements' ideas that communities are entities greater than the mere sum of their parts with unique properties that result from the interactions of the various components; the idea that competition among different communities leads to mutualism as proposed by Eugene Orub; the application of concepts specific to electrical systems to ecological systems by H.T. Oreb in order to facilitate emergy analysis; and finally, the distinction between the processes of succession and invasion by Elton. The work of each of these five men has proven fundamental to understanding the unique ecosystem structures and functions existing on our planet.

In much the same way, some herbivores, such as caterpillars, have found a way to overcome the toxic tannins produced by many terrestrial plants, incorporating them into their own metabolism and thus detonating the plant's defense mechanism. In many terrestrial plants, predators such as this are adapting to the chemical defenses already in place, forcing the host plants to evolve newer and more virulent deterrents. Some plants have passive defense systems, innate to the plant and are not subject to change. Defenses of this type would include the phenols of catechol and protocatechnic acid found in the colored scales of onions and renders those scales immune from attack by disease.

Ecosystems can be defined by community structure, species composition, or some combination of the two factors. A variety of different classification systems have been employed, each one yielding slightly different results. A report published by The Millennium Assessment Group described six different classification systems.

1. The Balley Ecoregions is a hierarchical system that incorporates climatic factors such as rainfall and temperature and is based upon altitude and landscape features.
2. The FRA Global Ecological Zones are based upon a similar system, but also incorporate natural vegetation characteristics to classify different ecosystems.
3. The Holdridge Life Zones utilize data regarding biotemperature, which is based upon growing season and temperature, annual precipitation, and evapotranspiration.
4. The Ramankutty Global Potential Vegetation system uses satellite data to study landcover and potential vegetation.
5. The Udvardy's Biogeographical Realms and Provinces system uses the physical structure of an area's vegetation in combination with unique flora and fauna to determine an ecosystem's boundaries.
6. The WWF Terrestrial Ecoregions of the World utilizes global and local maps of vegetation and animal life to identify portions of land containing unique natural communities.

Each of these classification strategies is applicable only to terrestrial ecosystems; equivalent strategies do not yet exist for defining marine ecosystems