Freshwater Biome Essay

The Freshwater Biome By Lauren Finnis The freshwater biome is a complex biome that can be found all over the world. There are two major types of freshwater biomes. The first type is lotic or running which include rivers and streams. Lentic or standing is the second type; those include lakes and ponds. Since this biome is found worldwide, the species that reside in it can vary extensively, but usually it contains several species of fish, plants, and insects. Predation is a way of life in the freshwater biome. It is the main way food and energy are obtained by most of the organisms. The plankton, algae, and weeds that produce their own food through photosynthesis are eaten by the smaller fish like the minnows. Then larger fish like bass, trout, and pike eat these smaller fish. Finally birds, large mammals, and humans catch the large fish. In the freshwater biome, there are several examples of symbiosis. The relationship between the freshwater sponge and spongillafly is an example of paratism. The spongillafly lays its eggs on the sponge, and then they hatch and feed off the sponge. Another parasite is the flatworm. It resides in organisms such as the snail and can infect them with deadly diseases. There are also examples of commensalism in this biome. First is the relationship between small fish and the pond weeds; the fish hide between these weeds from larger fish. Another relationship of this type is the one between oysters and the mangrove trees. The oyster anchor and protect themselves with the roots of the tree. Finally there are also examples of mutaulistic relationships. For example some small fish enter clean the mouths of larger fish, and in exchange, they may eat whatever they clean out. There are several limiting factors in the freshwater biome. One of the most important is the availability of sunlight. In areas with little sunlight, photosynthesis can not occur; therefore, most plants can not live. Since  plants are the base of the food chain the whole ecosystem falls apart. Salinity is also a limiting factor. In freshwater areas, there must be a salinity of .05% or less for most organisms to survive. Humans are actually limiting factors also. We destroy and pollute habitats and eat the animals and plants in the biome. Population density in the freshwater biome varies greatly. In rivers or streams, density is usually lower in the faster moving biomes because organisms must fight the current. In lakes and ponds, the topmost areas usually are more dense because there is an ample supply of light for photosynthesis. The highest densities will probably be found in the more temperate areas that organisms can adapt to more easily. The carrying capacity of the freshwater biome depends on the size, location, and availability off light. Biotic potentials in the biome are most likely extremely large. This is because the main organisms are fish, which lay eggs in numerous amounts. Of course the carry and the biotic potential are rarely met because there are natural enemies and predator. There are also billions of one of the most deadly predator to the biome, humans.