Ecosystem

Ecosystem is a complex system made up of the numerous relations between its biotic and its abiotic components and the environment.

Animals and plants are the biotic components, whereas the light, the water, the ground, the rain, the climate are the abiotic  elements of the ecosystem.

Biotic elements have different roles in the ecosystem:

PRODUCTORS (green plants, algae and some bacteria) use solar energy to convert inorganic molecules like hydrogen into organic compounds. Productors use these compounds to live and  to grow up.

CONSUMERS  - Herbivorous beings can't produce their nourishment so they eat productors.

                         -Carnivorous beings eat herbivorous beings to live and grow up.

DECOMPOSERS (funguses and bacteria) eat the tissues of dead consumers.

The biomass of an ecosystem is the weight of his dry organic matter (pro unit of measure).

As you can see, there's a close relation between all these living beings, indeed they are part of a complex food chain, where energy is continuously transferred from an organism to another one. Because of "the second thermodynamic principle", there are some energy losses disguised as heat during all these transfers. Indeed plants receive more energy than herbivorous and herbivorous receive more energy than carnivorous.

There are two kinds of food chain:

•-          pasture chain, from green plants to carnivorous beings

•-          debris chain, where dead organic matter is decomposed.

These two chains are interconnected each other, that's why you speak about trophic chain and trophic levels.

In an ecosystem, abiotic matters can be split into 2 groups:

Macronourishing elements  ( like oxygen, nitrogen, hydrogen, carbon and calcium). Living beings need these elements in big quantities.

Micronourishing elements (like iron and magnesium). Living beings need these elements but in small quantities.

Some years ago, farmers started to use exceedingly  in their fields some pesticides which are dangerous for men and other organisms.

Take DDT for example: when the molecule reaches the sea, it slows down the photosynthetic activity of seaweeds, birds' eggs are frail and break easily during the hatching because they are poor in calcium, decreases the number of individuals population and humans relate to damage organs and systems.

In Borneo, for example,  people used DDT  to kill some bugs who are malaria holders. But this chemical compound killed many other bugs too (and of course all the organism who eat bugs and mice died). As a consequence, mice survived and caused numerous infectious diseases between the population of Borneo.

Ecosystems are fundamental  for human beings. Indeed they purify the water and the air and offer outstanding chances to develop economy and tourism around the world.

A wood, a lake, a beach, a river or the whole world can be thought like an ecosystem with its own features. Ecosystems that are close and have similar abiotic elements form a biome.

All these biomes are not stable: for example the extinction of a species, or human interventions change the ecosystem.

There are different kinds of natural Ecosystems:

Plant ecosystems are divided into:
- deserts
- savannah
- steppe
- temperate forests
- tropical forests
- boreal forests

Aquatic ecosystems are divided into:
- freshwater ecosystems: lakes and ponds, rivers and streams, swamps and marshes
- sea ecosystems: coral reefs, oceans, continental shelves, areas of slope of nutrients, estuaries.

On Earth, however, there are not only natural ecosystems, but also artificial ecosystem created by humans  to organize their lifestyle and their activities. These artificial ecosystems are fields, metropolises and villages.

The ecological succession is the "story" of an ecosystem. Indeed, during the march of time, pioneers (simple living beings that first managed to live in a particular "inhospitable" environment),change some of the environment's characters to make it comfortable for more complex living beings.                                 After numerous levels of evolution of these living beings, an ecosystem becomes stable.

A field is different from a natural ecosystem because:

•-          farmers delete all the vegetal and animal species that could endanger his plantation.

•-          farmers bring energy to the fields with pesticides and machineries

•-          harvest (biomass) is taken away from the field, that needs chemical fertilizers and pesticides to produce plants again. Many of these products contain substances like DDT that  very often endanger ecosystems and cause different problems to their species.

This is a great problem because unchanged ecosystems are fundamental  for human beings.

A wood is an ecosystem altered by human beings made up of woody beings. There are lots of woods of beech trees, birches and pine forests in FVG.

The most important woods' functions are:

•-          PRODUCTIVE

•-          PROTECTIVE

•-          TOURIST - RECREATIONAL

•-          NATURLISTIC and ENVIRONMENTAL

•-          HYGIENIC - SANITARY

A forest is the result of the interaction between different ecosystems in a wide area made up of woods. In a forest you can find pastures, freshwater systems and clearings.

Forestry consists in all the possible human interventions to benefit from forests but also to rescue them. Indeed human beings are rarely aware that their behavior (that sometimes isn't good) affects ecosystems very much and endangers them.

Man needs to compare and study different kinds of animals and plants, that's why he gives a specific name to every natural range.