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Alien species
A species occurring in an area outside of its historically known natural range as a result of intentional or accidental dispersal by human activities (also known as an exotic or introduced species).

Biodiversity—short for biological diversity—means the diversity of life in all its forms—the diversity of species, of genetic variations within one species, and of ecosystems. The importance of biological diversity to human society is hard to overstate. An estimated 40 per cent of the global economy is based on biologi­cal products and processes. Poor people, especially those living in areas of low agricultural productivity, depend especially heavily on the genetic diversity of the environment.

The management of human use of nature so that it may yield the greatest sustainable benefit to current generations while maintaining its potential to meet the needs and aspirations of future generations.

Conservation of Biodiversity
The management of human interactions with genes, species, and ecosystems so as to provide the maximum benefit to the present generation while maintaining their potential to meet the needs and aspirations of future generations; encompasses elements of saving, studying, and using biodiversity.

Cryptogenic species
In ecology, a cryptogenic species is one which may be either a native species or an introduced species, clear evidence for either origin being absent. An example is the Northern Pacific seastar (Asterias amurensis) in Alaska and Canada. (

A branch of science concerned with the interrelationship of organisms and their environment; the study of ecosystems.

Ecosystems are self-regulating communities of plants and animals interacting with each other and with their non-living environment—forests, wetlands, mountains, lakes, rivers, deserts and agricultural land­scapes. Ecosystems are vulnerable to interference as pressure on one component can upset the whole bal­ance. They are also very vulnerable to pollution. Many ecosystems have already been lost, and many others are at risk.

Eco Tourism
Travel undertaken to witness sites or regions of unique natural or ecologic quality, or the provision of serv­ices to facilitate such travel that have the least impact on biological diversity and the natural environment.

Ecological Impact Zone:
Ecological impact zone can be defined as an area a resource merging into a marine area ecologically influences. To illustrate, the ecological impact zone of Danube river flowing into the Black Sea is the whole Danube basin where this river is the receiving environment. The zone ecologically affecting this river has been broadly defined by the concept “basin”.  The marine zone the Danube river dominantly affects has been called as “Danube Delta” in the area where the Danube river flows into. However, it is widely known that the Danube river affects a large area extending to Istanbul Strait in the Black Sea, and even to The sea of Marmara. That is, although its ecological impact has been dominantly observed in the delta area, it has a substantial influence over a large area depending on both its capacity and the current systems in Black Sea in the area where the river ultimately pours.  In this respect, the ecological impact zone of Danube River extends to The sea of Marmara.
The Ecological Impact Zone of a source may alter depending on the size of the water source (flow rate for a river), size of the area it impacts on (basin for a river) and the current systems in the area where it merges into the sea.
The source concerned is not only limited to rivers. The ecological impact zone of any kind of source in different ecological characteristics merging into a marine area can be defined. For instance, the Red Sea influences the eastern Meditarennean through the Suez Canal. Likewise today the species coming from the Suez Canal spread over the Agean Sea even to the Sea of Marmara under the influence of the global climate change. With the effect of the changing environmental circumstances (global warming in the subject example), the ecological impact zone also changes. That’s to say, the range of theecological impact zone may vary along with the changing ecological circumstances. It can be alleged the bigger the difference between the ecological factors of the two different intermingling ecosystems, the smaller the ecological impact zone under the influence of one another. The ecological impact zone will enlarge as the ecological circumstances are closer to one another.
In conclusison, a source coming from a different ecosystem and mingling into any marine environment influences an area depending on its size, continuity, currents in the receiving environment and other mass water movement. This is called “ecological impact zone”. The size of this zone is not fixed and may vary depending on the changing circumstances.

Endangered species
A technical definition used for classification referring to a species that is in danger of extinction through­out all or a significant portion of its range. IUCN The World Conservation Union defines species as endan­gered if the factors causing their vulnerability or decline continue to operate.

The evolutionary termination of a species caused by the failure to reproduce and the death of all remaining members of the species; the natural failure to adapt to environmental change.

All of the animals found in a given area.

All of the plants found in a given area.

A place or type of site where an organism or population naturally occurs.

Habitat degradation
The diminishment of habitat quality, which results in a reduced ability to support flora and fauna species. Human activities leading to habitat degradation include polluting activities and the introduction of inva­sive species. Adverse effects can become immediately noticeable, but can also have a cumulative nature. Biodiversity will eventually be lost if habitats become degraded to an extent that species can no longer survive.



Habitat fragmentation
Fragmentation of habitats occur when a continuous has become divided into separate, often isolated small patches interspersed with other habitats. Small fragments of habitats can only support small populations of fauna and these are more vulnerable to extinction. The patches may not even be habitable by species occupying the original undivided habitat. The fragmentation also frequently obstructs species from immi­grating between populations. Habitat fragmentation stems from geological processes that slowly alter the lay out of the physical environment or human activities such as land clearing, housing, urban development and construction of roads or other infrastructure. Adverse effects sometimes are not immediately notice­ able and sufficient habitats may ostensibly be maintained. However inbreeding, lack of territories and food shortage are some of the problems small populations can encounter. Fragmentation of habitats is therefore expected to lead to losses of species diversity in the longer term.

Habitat loss
The outcome of a process of land use change in which a ‘natural’; habitat-type is removed and replaced by another habitat-type, such as converting natural areas to production sites. In such process, flora and fauna species that previously used the site are displaced or destroyed. Generally this results in a reduction of biodiversity.

Indicator species
A species whose status provides information on the overall condition of the ecosystem and of other species in that ecosystem.

Invasive species
Invasive species are those that are introduced—intentionally or unintentionally—to an ecosystem in which they do not naturally appear and which threaten habitats, ecosystems, or native species. These species become invasive due to their high reproduction rates and by competing with and displacing native spe­cies, that naturally appear in that ecosystem. Unintentional introduction can be the result of accidents (e.g. when species escape from a zoo), transport (e.g. in the ballast water of a ship); intentional introduction can be the result of e.g. importing animals or plants or the genetic modification of organisms.

Marine Protected Area
An area of sea (or coast) especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means.

Native species
Flora and fauna species that occur naturally in a given area or region. Also referred to as indigenous species.

Population: A population in the biological sense is a reproductive community of individuals of a species that is more or less separated from other populations. For example, populations of trout found in different lakes.

Protected Areas
An area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means. A protected area can be under either public or private ownership.

Red List
The IUCN Red List of Threatened Species provides taxonomic, conservation status and distribution infor­mation on taxa that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those taxa that are facing a higher risk of global extinction (i.e. those listed as Critically Endangered, Endangered and Vulnerable). The IUCN Red List also includes information on taxa that are categorized as Extinct or Extinct in the Wild; on taxa that cannot be evaluated because of insufficient information (i.e. are Data Deficient); and on taxa that are either close to meeting the threatened thresholds or that would be threatened were it not for an ongoing taxon-specific conservation programme (i.e. are Near Threatened).

The recovery of specific ecosystem services in a degraded ecosystem or habitat.

The return of an ecosystem or habitat to its original community structure, natural complement of species, and natural functions.

A group of organisms capable of interbreeding freely with each other but not with members of other species.

Species diversity
The number and variety of species found in a given area in a region.

Sustainable use
The use of components of biological diversity in a way and at a rate that does not lead to the long-term decline of biological diversity, thereby maintaining its potential to meet the needs and aspirations of present and future generations.

The classification of animals and plants based upon natural relationships.

Threatened species
A technical classification referring to a species that is likely to become endangered within the foresee­able future, throughout all or a significant portion of its range. 12,259 species are known by IUCN, the World Conservation Union, to be threatened with extinction. IUCN keeps the world’s inventory of the conservation status of animals and plants, compiling data from thousands of scientists and conservation­ists worldwide. However, the 12,259 threatened species are only the tip of the iceberg. Nobody knows how many species there are on Earth, let alone how they are doing. The total number of recorded living species is around 1.75 million. But more than two thirds are insects and other invertebrates, which are extremely difficult to monitor. An estimate of the real number of species on Earth is 14 million. For its 2003 “Red List of Threatened Species”, IUCN was able to evaluate the conservation status of 2% of 1.53 million species for which it has descriptions. The only two well-monitored groups are birds and mammals, so IUCN was able to evaluate 100% of birds and 99% of mammals for threatened status.