Ecosystem and Biodiversity

CoordinatorOIKONOMOUDIS IOANNIS

Ecosystem

All the components of the ecosystem are located in close relationship and in interdependence.

Ecosystem construction

Primary producersPrimary producers are the organisms in an ecosystem that produce biomass from inorganic compounds (autotrophs). In almost all cases these are photosynthetically active organisms (plants, cyanobacteria and a number of other unicellular organisms.

cyanobacteria algae

Plant species

Consumers are organisms of an ecological food chain that receive their energy by consuming other organisms. These organisms are formally referred to as heterotrophs, which include animals, bacteria and fungus. Such organisms may consume by various means, including predation, parasitization, and biodegradation.

Consumers

Decomposers or saprotrophs are organisms that break down dead or decaying organisms, and in doing so carry out the natural process of decomposition.

Decomposers

Food chains

Food web in a forest

The forest ecosystem

When upper kinds of plants (trees, bushes) dominate in the plant community of the ecosystem the forest ecosystem appears. Therefore, the forest is an ecosystem, in the plant community where the upper plants (trees, bushes) are dominant.

Forest There are all possible relationships in the biotic community of forest, from simple coexistence, incremental space competition, light, water and nutrients, to the mutual interdependence between its members. All those relationships create a dynamic balance, which constantly changes. So the forest isn't something which remains static, but it changes and develops continuously. The forest is born, goes to its adulthood, matures and grows older and eventually dies to be reborn. A forest distinguishes to virgin, natural and artificial forest.

• The forest ecosystems play an important role in the ecological balance of the planet and cover the 32% of the surface of earth. The production of oxygen, as the consumption of carbon dioxide with the operation of the photosynthesis from the plants is increased in forests.

Cornus mas - ΚρανιάCistus creticus - ΛαδανιάCorydalis integra Κορυδαλός

Plants we have found in Cholomontas forest - Greece

Crocus flavus - κρόκος Erica manipulifloraρείκι το μελισσοτροφικό

Fragaria vesca αγριοφραουλιά

Ranunculus ficariaΝεραγκούλα

Romulea bulbucodiumΡομούλεα

Scilla bifoliaΣκίλα η δίφυλλη

Helleborus cyclophyllus σκάρφι Helleborus cyclophyllus σκάρφι νεαρό φυτό Ilex cornuta αρκουδοπούρναρο

Tree species

fagus orientalis – οξιά quercus fraineto - δρυς

Juniperus oxycedrus - Κέδρος

Pinus nigra – Μαύρη πεύκη

Podarcis muralis – Lizard species

Mushrooms

Moss & Lichens

Lichens on fagus sylvatica

Moss on a rock

Biodiversity

Biodiversity embraces the variety of genes, species and ecosystems that constitute life on Earth. We are currently witnessing a steady loss of biodiversity, with profound consequences for the natural world and for human well-being. The main causes are changes in natural habitats.

Why Preserve Biodiversity? What happens if one member of an ecosystem no longer exists? For example, what might happen if a certain type of fish(marked with X) dies out of a lake ecosystem, leaving its predators without a food source and its prey without a predator?

The food chain might collapse with unpredictable consequences for the Ecosystem

Biodiversity and ecosystem services• Provisioning services which involve the production of

renewable resources (e.g.: food, wood, fresh water).• Regulating services which are those that lessen

environmental change (e.g.: climate regulation, pest/disease control).

• Cultural services represent human value and enjoyment (e.g.: landscape aesthetics, cultural heritage, outdoor recreation, and spiritual significance)

Services enhanced by biodiversity• Greater species diversity of plants increases fodder

yield, decreases disease prevalence on plants and increases resistance to plant invasion, soil nutrient remineralization and soil organic matter.

• Greater genetic diversity of plants (i.e.: diversity within a single species) increases overall crop yield.

• Greater species diversity of trees increases overall wood production.

• Greater species diversity of fish increases the stability of fisheries yield.

• Greater species diversity of natural pest enemies decreases herbivorous pest populations.

Some benefits from human point of view for preserving biodiversity

• Economic: "Biodiversity can help people make money or keep people from losing money."

• Recreational: "People love outdoor activities like fishing and backpacking, which would not be possible if ecosystems were destroyed."

• Human health: "Biodiversity can help people find better cures for illnesses."

• Human rights: "If biodiversity is protected, indigenous people can continue to live in their native lands."

• Spiritual/intrinsic value: "Biodiversity should be preserved for its own sake," "Animals and plants have a right to live," and "People rely on wild places and creatures for spiritual fulfillment."

The Meaning of Biodiversity

• Τhe number of organisms that live on the earth participate in almost all processes that occur.

• It’s the basis for many industrial products, as well as for the production of numerous medicines.

• The elimination of a certain plant or animal creates such a great loss that no natural or technological mechanism can recreate.

ExtinctionA species becomes extinct when the last existing member dies. Extinction therefore becomes a certainty when there are no surviving individuals that are able to reproduce and create a new generation. A species may become functionally extinct when only a handful of individuals survive, which cannot reproduce due to poor health, age, sparse distribution over a large range, a lack of individuals of both sexes (in sexually reproducing species), or other reasons.

Criteria evaluation of living organisms based on the probability of extinction- IUCN Red List

■ EXTINCT (ΕΧ):Species where all the members are dead

■ EXTINCT IN THE WILD (EW):Species that occur only in cultivations, away from their natural environment or being prisoned.

■ REGIONALLY EXTINCT (RE):Species that have extinct in national region.

What cause the extinction of animals and plants?

• People's consumption of plants and animals is much faster than their production.

• The animals cannot produce as much as they could because their habitats are being abused. For ex: the forest, and if their habitats are being abused, it will become hard for them to live.

• Destruction of habitat also aids in extinction.

■ CRITICALLY ENDANGERED (CR):Species where are in imminent danger of extinction in their natural environment.

■ ENDANGERED (ΕΝ):An endangered species are species of organisms facing a very high risk of extinction in the near future.

■ VULNERABLE (VU):Species which are not ranked in these categories but facing a risk of extinction in the future.

Endangered species • It has been estimated that over 40% of all living

species on Earth are at risk of going extinct. Internationally, 199 countries have signed an accord agreeing to create Biodiversity Action Plans to protect endangered and other threatened species.

• IUCN Red List refers to a specific category of threatened species, and may include critically endangered species.

■ NEAR THREATENED (NT):Species are not ranked in the above categoriesbut are close to be endangered in the future.

■ LEAST CONCERN (LC):Species are not in danger of extinction

■ DATA DEFICIENT (DD):Species where we need more research.

■ NOT EVALUATED (ΝΕ):Species we must evaluate the danger of extinction.

ΣΑΣ ΕΥΧΑΡΙΣΤΩ!THANK YOU!