Concept and Classification of Biomes

A biome, also called bioclimatic landscape or biotic areas is a particular part of the planet that shares climate, flora and fauna. A biome is the set of characteristic ecosystems of a biogeographic region that is defined from vegetation and animal species predominate. It is the expression of the ecological conditions in the regional or continental level: the climate and soil determine the ecological conditions that respond communities of plants and animals of the biome in question.

Depending on the latitude, temperature, rainfall and altitude, you can divide the land into areas with similar characteristics; in each of these areas vegetation and fauna that develops when linked define a biome, comprising the notions of community and interaction between soil, plants and animals.

There are different biome classification systems, which generally tend to divide the land into two large groups terrestrial biomes and aquatic biomes.

• Terrestrial ecosystem: are those in which the flora and fauna develop in the soil or subsoil. Depend on humidity, temperature, altitude and latitude, so that the most biologically rich and diverse ecosystems is higher humidity, higher temperature, lower altitudes and lower latitudes.

Ecosystems can be classified according to the type of vegetation, finding the greatest biodiversity in forests, and this decreases in the bush, grasslands, into the wilderness. Depending on the density of the dominant vegetation, can be open or closed.

Among the major terrestrial ecosystems are:

1- Forests: forest ecosystems, forests form the largest mass of terrestrial biosphere. May be:

*Hardwood forest or broadleaf forests: mostly formed by trees bloom.

- Jungles: ecosystems with the greatest biological density, higher rainfall and evergreen vegetation. The climate determines different types: According latitude and temperature can be tropical or subtropical rainforest, according to seasonality and moisture is rainy or monsoon forest and according to altitude mountain jungle or basement. They are complex, the canopy and understory are considered markedly different subecosystems. The most extensive and diversified forest is the equatorial forest, which is basal-rainy-tropical type.

- Dry forest: tropical and subtropical forests with a long dry season and a short rainy, so abundant desert vegetation and deciduous.

- Temperate deciduous forest: in less humid Mediterranean forest and deciduous forest develops; in wetter regions is the laurifolio forest or temperate forest.

*Conifer forest or forest leaf acicular: composed primarily of gymnosperms such as conifers. 

- Taiga or Boreal Forest: forest of greater length but less biodiversity. It has about 4 months favorable season. The soil lichens and moss.

- Temperate coniferous forest: pine, cedar, fir and redwood, among others, which are among the highest in the world.

- Tropical and subtropical coniferous forests: subhumid forests, mainly pine.

2- Bushes: the bush or scrub ecosystems are those shortest plants such as shrubs and bushes. May be:

- Shrub: Depending on the region and type of bushes received various names such as chaparral, Mediterranean scrub, heathland, jaral and fynbos.

- Xeric: The desert scrub consists mainly of thorns as cacti and bromeliads in semi-desert regions.

- Alpine Tundra: has mountain brush, whose bushes are often called frailejones. They are wet ecosystems of high altitude and latitude equatorial own America, Africa and New Guinea.

3- Grasslands: arable or grassland ecosystems are those predominance of herbs and media often seasonally semiarid climate. May be:

- Meadow: temperate climate and green most of the year dominance of the wet season. They are easily transformed into agricultural land.

- Steppe: from warm to cold weather and yellowing most of the year dominance of continental arid climate.

- Savanna: tropical and subtropical climate, usually limited to the jungle. Seasonality leads to the migratory habits of wildlife. The absence or presence of irregular shrubs or trees leads to grassy savanna ecosystems, shrub savanna and forest or wooded savannah.

- Alpine meadow: also called mountain meadow, alpine tundra or mountain grassland. They are of high altitude ecosystems. In the Andes stand tall grasslands. It is also found in the Alps, Tibet and others.

4- Tundra: consists of mosses, lichens, grasses and small shrubs, so it really is a wetland ecosystem defined by the absence of trees and having the frozen subsoil. They are among the taiga and perpetual snow. The Arctic tundra has great extent in the Antarctic are small areas and alpine tundra is best defined as mountain meadow.

5- Desert: are divided into two:

- Desert itself: they have very little flora and fauna. They are typical of subtropical climates, 

but can also be found in tropical, temperate and cold areas in the mountains.

- Ice cap: the ice or polar desert. The ecosystem has more development on the coast or ice edge.

6- Human Ecosystem: natural ecosystem is not controlled or human intervention.

- Urban environment.

- Media rural farm and crop fields, breeding, mining, logging, etc.

- Artificial and semi-natural ecosystems: the creation of forests, ponds, introduction of new species, abandonment of farmland, desertification, etc.

• Aquatic ecosystem: include the waters of the oceans and inland waters sweet or savory. Each of these bodies of water has particular structures and physical properties with respect to light, temperature, waves, currents and chemical composition as well as different types of environmental organizations and distribution of organisms.

1- Marine ecosystem: oceanography is the study of these ecosystems. Can be of two types depending on receiving sunlight:

- Photic: when receiving enough light for photosynthesis, which happens to 200 m depth. Examples of such ecosystems are the beach or seaside, the continental shelf, open ocean, coral reef atoll lagoon, river mouth, etc.

- Aphotic: where sufficient light for photosynthesis fails. As in the shallow sea, deep, abyssal, sea ocean trench and most of the seabed.

2- Freshwater ecosystem: limnology is the study of ecosystems of rivers and lakes. This group not only considered running water ecosystems (lotic means) and still water (lentic media) but also watery habitats springs, hollow trees and even pockets of plants where water collects and environments groundwater.

Food and Non Food Relations

Every ecosystem consists of a large set of relationships. Some relationships are easier to determine than others, and some effects are evident whereas others are unseen. Although most ecological relationships occur when there is some sort of interaction between two species, there are some instances in which a relationship is built on nothing at all except being in the same area.

-Mutualism: is an ecological relationship that occurs between two species that both benefit from the partnership. The things gained by each party are usually different. These partnerships can be based around food, such as cases in which one species gains a meal and the other gains a health boost. Wild birds in grasslands often follow herds of hoofed animals such as zebras and antelope, then feed off the pests carried in their fur. The birds get a meal, and the larger animals get protection from mites and fleas. 

-Predator and Prey: the relationship between a predator and its prey is perhaps one of the most evident and clearly visible in the natural world. Predators can be at the top of the food chain or in the middle, and not all predators are animals or feed on other animals; the relationship simply means that one life form consumes another.

Traditional examples of a predator and prey relationship include a fox and a rabbit or an owl and a mouse. This type of ecological relationship can also be applied to situations wherein the deer is the predator and the grass is the prey or the pitcher plant is the predator and the fly is the prey.

-Parasitic: a parasitic relationship is one in which two species live in close contact with each other and one benefits whereas the other is harmed. In most cases the host is not killed, as they are more valuable to the parasite when they are alive.

Insects are some of the most common parasites. Fleas and ticks infest both wild and domestic animals, feeding off their blood while causing bites, sores, scabs and itching. Other parasitic relationships involve creatures like tapeworms living inside a host and stealing nutrients. Parasites attack plants as well as humans and animals, sucking out juices and water from leaves and stems.

-Neutralism: is a type of ecological relationship that occurs when two species live in the same area and neither has a positive or negative effect on the other.

For example, two species of birds can share the same tree; one species builds nests and eats mainly seeds whereas the other lives in the hollows of the tree and eats mainly insects. There is no competition for food or for shelter, and neither bird relies on the other for any kind of support.

-Commensalism: is a symbiotic relationship in which one party has a definite benefit from its relationship with another species while that other species is not harmed or helped by the partnership. This often occurs when one species is providing protection, a home or transportation to another without gaining anything in return. A tree provides a home for birds with no return benefit, much as sharks provide a place for barnacles to adhere to. 

In some cases, such as the example with the shark and barnacle, the benefit to one species can be twofold. Not only do barnacles have a place to adhere to that keeps them safe from predators, but they can also feed off the shark's leftovers.

Categories of Organisms

1- System Two kingdoms: the first organization kingdoms is due to Aristotle who distinguished all living entities of nature into two kingdoms: plants and animals. The first characterized by having "vegetative soul" which gives reproduction, growth and nutrition; the second additionally has "sensitive soul" which gives addition to the above perception, desire and movement.

Linnaeus also distinguished these two kingdoms of living things and also treated minerals, placing them in a third kingdom, Lapides. It also introduced the binomial nomenclature to refer to species and kingdoms divided into classes, classes into orders, orders into families, families into genera and species genera.

2- System Three Kingdoms: in 1858 R. Owen noted the difficulty of classifying microbial plant and animal beings, he suggested creating the kingdom Protozoa and defined as tiny beings mostly formed by nucleated cells.

In 1860 the English biologist John Hogg, posits the third kingdom, called "Regnium primigenium" or Protoctista for protozoa, protófitos and simple shapes. Hogg actually spoke of four kingdoms: animal, vegetable, and mineral primal.

In 1866 Ernst Haeckel called the third kingdom Protista and defined it as the "primordial" the kingdom of early and intermediate forms between Animal and Plantae kingdoms. Acknowledged the problem of classification by the presence of animal characters, and mixed vegetables, but necessary for systematic purposes. He was the first to distinguish between unicellular organisms (protists) and multicellular (plants and animals).

3- System Four kingdoms: the concept of the third kingdom was questioned by Otto Bütschli in the 1880s, as it was considered to Protista as polyphyletic, especially the inclusion of bacteria.

Herbert Copeland in its publications separates nucleated protists bacteria in the system enucleated following four kingdoms: Plantae (or Metaphyta), Animalia (or Metazoa), Protoctista (or Protista) and Mychota (or Monera) for bacteria and viruses.

4- System Five Kingdoms: Robert Whittaker recognized an additional kingdom of fungi (Fungi). The result was the system of the 5 kingdoms, proposed in 1969. It is based mainly on differences in nutrition: Plantae are mostly multicellular autotrophs, heterotrophs Animalia and Fungi multicellular multicellular saprophytes. The other two kingdoms, Protista and Monera (prokaryotes) include unicellular or colonial organisms.

5- System Six Kingdoms: Carl Woese and Fox G. divided in 1977 moneras prokaryotes or two super-kingdoms Eubacteria and Archaea. In 1990, Woese renamed the new groups so ran the system consists of three domains Bacteria, Archaea and Eucarya.

These two prokaryotic groups Archaea (or Archaebacteria) and Bacteria (or Eubacteria), are considered kingdoms along with plants, animals, fungi and protists, which is the system of six realms, a system that has become standard.

The kingdoms have the following characteristics:

-Bacteria: are the most abundant creatures on the planet, with a variety of habitats and metabolisms. found in all terrestrial and aquatic habitats; grow up in the most extreme and hot springs and acidic waters, radioactive waste and in the depths of both the sea and the earth's crust.

-Archaea: are a group of unicellular prokaryotic microorganisms morphology (coreless or internal membranous organs).

-Protista: are the simplest eukaryotes, form a group consisting of protozoans, algae and slime molds.

-Plantae: photosynthetic beings are living without locomotor ability and whose cell walls are composed mainly of cellulose; is comprised of land plants and algae that relate to them.

-Fungi: is a group of eukaryotic organisms among which are the molds, yeasts and mushrooms.

-Animalia: are a major group of eukaryotic organisms, heterotrophic, multicellular tissue. They are characterized by their capacity for locomotion, the absence of chlorophyll and wall in their cells, and embryonic development, passing through a blastula stage and determines a fixed body plan.

Structure of an Ecosystem

Trophic levels are categories in which living things are classified according to their way of obtaining materials and energy; Moreover, the trophic level of an organism is its position in the food chain.

         And that living things need energy to perform all vital functions, which is obtained from the sun and is captured by plants through photosynthesis which transform it into food. Then, at this point energy transfer is initiated, which passes from plants to herbivores and from herbivores to carnivores. And so a food relationship between the various bodies within the ecosystem is established.

         The different components that make up the structure of an ecosystem are based on their respective roles on the environment; the structure are divided into biotic and abiotic.

• Biotic: are living things in an ecosystem to survive, those with life. They may relate to the flora, fauna, humans from a particular place and their interactions. Individuals must have specific behavioral and physiological characteristics that allow their survival and reproduction in a defined environment. The condition of sharing an environment engenders competition among species, given for food, space, etc. It structure is based on: 

-Producers or Autotrophs: are organisms that are able to manufacture or synthesize their own food from inorganic substances such as carbon dioxide, water and mineral salts. Plants are autotrophs.

-Consumers or heterotrophs: they feed on organic substances already developed by other organisms, which feed on substances made by the producers or other consumers. Consumers also can be:

* Consumers Primary or First-Order (herbivores): are those that feed directly from plants, and this is the greatest advantage that energy reserved by the producers. Some primary consumers are rodents, insects, birds, lapwings, cow, sheep, among others.

* Consumers Secondary or First-Order Carnivora: those that eat primary consumers, but their diets are called carnivores. Within this group we find the zooplankton, some fish, opossums, snakes, frogs, among others.

*Consumers Secondary Tertiary or Carnivores: those that eat other carnivores such as raptors and cats. Within this group we find omnivores that eat both plants and animals.

-The Decomposers and Detritivores: when a plant or animal dies the bodies are disintegrated by other agencies, decomposers, which are represented by bacteria and fungi; and detritivores, which are represented by small worms, earthworms, protozoa, snails, slugs, millipedes, among others; within this group large scavengers, organisms that feed on carrion like vultures and crows are located.

         Also, the decomposition can be defined as the gradual disintegration of dead organic matter, in which complex energy-rich molecules are fragmented by decomposers and detritivores. It is for this reason that organisms belonging to this trophic level have a key role in the cycling of matter because "close" food chains in cycles, allowing organic matter is transformed into inorganic and can be captured by producers.

The other part of the structure of an ecosystem is the abiotic factor, which are the different components that determine the physical space in which living organisms; among the most important we find: water, temperature, light, pH, soil moisture, air and nutrients.

Specifically, are the factors lifeless.

What is an Ecosystem?

An ecosystem is a unit composed of interdependent organisms that share the same habitat. Ecosystems usually form a series of chains that show the interdependence of organisms within the system. It can also be defined as: "An ecosystem consists of the biological community of a place and the physical and chemical factors that constitute the abiotic environment."

An ecosystem includes all of the living things like plants, animals and organisms in a given area, interacting with each other, and also with their nonliving environments like weather, earth, sun, soil, climate, atmosphere.

Levels of organization in an ecosystem

-Individual: is any living thing or organism; individuals do not breed with individuals from other groups. Animals, unlike plants, tend to be very definite with this term because some plants can cross-breed with other fertile plants.

 -Population: a group of individuals of a given species that live in a specific geographic area at a given time.  Note that populations include individuals of the same species, but may have different genetic makeup such as hair/eye/skin colour and size between themselves and other populations.

-Ecosystem Community: this includes all the populations in a specific area at a given time. A community includes populations of organisms of different species; a great community usually includes biodiversity.

-Ecosystem:  ecosystems include more than a community of living organisms interacting with the environment. At this level they depend on other abiotic factors such as rocks, water, air and temperature.

-Ecosystem Biome: is a set of ecosystems sharing similar characteristics with their abiotic factors adapted to their environments.

-Ecosystem Biosphere: when we consider all the different biomes, each blending into the other, will all humans living in many different geographic areas, we form a huge community of humans, animals and plants, in their defined habitats. A biosphere is the sum of all the ecosystems established on Earth.