Habitat & Niche
Organisms can be found living everywhere across the globe. From the searing heat of desserts like the Sahara to the icy cold of both
Antarctica and our own Canadian Arctic. Life is everywhere.
The place where living organisms survive and carry on from generation to generation is called their HABITAT.
The word habitat means the physical space where the species is found. A habitat describes the area and particular environment in which
the organism can and does survive. In any particular habitat many different species can coexist together.
A NICHE refers to the organism’s role or job in that community of habitat. A species roll in a community depends entirely upon
what habitat it is found in, NOT on what the species is. For example, take a snake. A snake living in a forest has a rather different role to
play than one living in the Arizona desert. They will eat different foods, hunt different prey, etc. Each creature in a habitat will have its own
roll or niche to play for the community to be a successful ecosystem; different species will consume different foods and have different needs.
Feeding Relations
Predator-Prey
A predator is a creature that hunts and kills its own food. Predators are secondary or higher consumers. Most animals are part
of this relationship: herbivores are often the prey of the hunter predator.
Parasite - Host
A parasite is another type of consumer, however a parasite main aim is not to kill its victim but to use the victim as a source of
food and a place on which to live. This so called victim is called a host. The parasite may, for example suck the blood out of its host victim,
but it doesn’t want to take all the blood. That would kill the parasite source of food. A victim usually dies from parasites when its body
becomes overwhelmed by sheer numbers of parasites or the parasite is vector for bacteria, germs or viruses. For example, a mosquito
bite in Algonquin Park is no big deal, however a mosquito bite in the tropics could lead to malaria.
Scavengers
A scavenger is an organism that eats dead or decaying plant and animal matter. Scavengers are considered to be the clean-up crew of an
ecosystem. Snails in an aquarium will eat dead fish, but they also eat algae and plants. As such they are also herbivoirs.
Ring-billed gulls act as scavengers when they eat dead fish washed up onto a beach.
Decomposers
When an organism dies, the nutrients that are part of it are not in a sueful form to the producer until they are chemically broken down or
decomposed . Organisms that carry out this function (their niche in an enevironment) are called decomposers.
Decomposers are organisms such as moulds and bacteria, that penetrate dead material and digest it. As they decompose the dead material
they return valuable nutrients to the soil. These nutrients can then be used again by plants (producers) to help them grow. In this way,
useful materials are being recycled in the community. A back yard composter facilitates this breakdown action.
Cycles Found in Nature
The first cycle mentions is a complete Food Web in which scavengers and decomposers convert all dead biotic material into
reusable materials. Such material is often referred to as fertilizer. Also dead material may become the food for other creatures especially
insects which will lay eggs in the decaying flesh so that the hatching young have a ready available supply of food. Bacteria and fungi will
continue the complete breakdown of the complex cellular structure of these once living cells.
This cycle is called the Nutrient Cycle.
In this cycle, material moves from the producer to the consumer and eventually some of this material is returned to the producers by
decomposers.
Three other important cycles found in nature are
- the water cycle
- the carbon cycle
- the nitrogen cycle.
In each of these cycles water, carbon (the building block of all life) and nitrogen (an essential component of amino acids)
are used then returned to the environment to be reused again and again.
Soil Notes
Nature of Soils from Stony Brook University of Long Island. This site gives a summary of soil types with some emphasis to Long Island soils but cna be applied to any area. Just
CLICK HERE