February 10, 2012

Ecological Communities, Ecological Habitat and Ecological Niche

Ecological Community

-An ecological community is defined as a group of actually or potentially interacting species living in the same place.


Ecological Niche

-The Ecological Niche of an organism describes how that particular individual "fits" into its ecosystem. Within its habitat, it must make use of available resources, withstand abitoic and biotic factors, with the help of adaptations. In other words, a niche is the role that the individual organism plays in its nonliving and living environment. 

Ecological Habitat

-Technically, a habitat is where a specific species lives, and describes the location in physical terms (ocean, salt marsh, sandy beach). A "biome" is a type of habitat unassociated with a species. For example, you will find the "boreal forest" biome in two continents, but only one of them is habitat for the north American Snowy Owl.

11 Characteristics of Living Things

Defining "life" is a very difficult task, and scientists don’t all agree on a common list of the characteristics of life. Some of the other characteristics that the students may discover in their research, and which are often listed in textbooks, include those listed below. Many of these traits are not limited to living things. For example, fire uses energy, grows, and can reproduce, but it is not considered alive in part because it cannot evolve; its traits are necessary, but not sufficient, for life. NASA scientist Bruce Jakosky, in his book The Search for Life on Other Planets, provides a generally accepted definition of something being “alive” if it 1) utilizes energy from some source to drive chemical reactions, 2) is capable of reproduction, and 3) can undergo evolution.

Characteristics of Living Things
  • All organisms use energy (metabolism).
  • All organisms maintain a stable internal environment (homeostasis).
  • All organisms detect and respond to select external stimuli.
  • All organisms can engage in movement (which may occur internally, or even at the cellular level).
  • All organisms show growth and development; that is, specialization of cells or structures. (Even unicellular organisms show a tiny amount of growth, and single cells repair and use materials from the environment to replace internal structures as needed.)
  • All organisms reproduce. (Even if an individual can’t reproduce, its species can.) In addition, an individual’s cells are constantly reproducing themselves.
  • All organisms have nucleic acid as the hereditary molecule.
  • All organisms show adaptation, which occurs at the individual level and is tightly related to homeostasis.
  • All organisms are made of one or more cells.
  • All organisms exhibit complex organization, grouping molecules together to form cells; at a higher level, cells are organized into tissues, organs, and organ systems.
  • All organisms exhibit evolution over time due to mutation and natural selection (which operates at the species level).

Components of Ecosystem

There are two components: ABIOTIC AND BIOTIC COMPONENTS

ABIOTIC COMPONENTS:
Sunlight
Temperature
Precipitation
Water or Moisture
Soil or water chemistry

BIOTIC COMPONENTS:
Primary Producers
Herbivores
Carnivores
Omnivores

However these are some other abiotic and biotic components:

OTHER ABIOTIC COMPONENTS

Abiotic components are such physical and chemical factors of an ecosystem as light, temperature, atmosphere gases(nitrogen, oxygen, carbon dioxide are the most important), water, wind, soil. These specific abiotic factors represent the geological, geographical, hydrological and climatological features of a particular ecosystem. Separately:

* Water, which is at the same time an essential element to life and a milieu
* Air, which provides oxygen, nitrogen, and carbon dioxide to living species and allows the dissemination of pollen and spores
* Soil, at the same time source of nutriment and physical support. The salinity, nitrogen and phosphorus content, ability to retain water, and density are all influential.
* Temperature, which should not exceed certain extremes, even if tolerance to heat is significant for some species
* Light, which provides energy to the ecosystem through photosynthesis
* Natural disasters can also be considered abiotic. According to the intermediate disturbance hypothesis, a moderate amount of disturbance does good to increase the biodiversity.


OTHER BIOTIC COMPONENTS

The living organisms are the biotic components of an ecosystem. In ecosystems, living things are classified after the way they get their food.

Biotic Components include the following:

Autotrophs produce their own organic nutrients for themselves and other members of the community; therefore, they are called the producers. There are basically two kinds of autotrophs, "chemoautotrophs and photoautogrophs. "

Chemautotrophs are bacteria that obtain energy by oxidizing inorganic compounds such as ammonia, nitrites, and sulfides , and they use this energy to synthesize carbohydrates.

Photoautotrophs are photosynthesizers such as algae and green plants that produce most of the organic nutrients for the biosphere.

Heterotrophs, as consumers that are unable to produce, are constantly looking for source of organic nutrients from elsewhere. Herbivores like giraffe are animals that graze directly on plants or algae. Carnivores as wolf feed on other animals; birds that feed on insects are carnivores, and so are hawks that feed on birds. Omnivores are animals that feed both on plants and animals, as human.

Detritivores - organisms that rely on detritus, the decomposing particles of organic matter, for food. Earthworms and some beetles, termites, and maggots are all terrestrial detritivores.

Nonphotosynthetic bacteria and fungi, including mushrooms, are decomposers that carry out decomposition, the breakdown of dead organic matter, including animal waste. Decomposers perform a very valuable service by releasing inorganic substances that are taken up by plants once more.