Bio- and landscape diversity Theme 2 Theme

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Bio- and landscape diversity: Theme # 2 Theme 2: What is Biodiversity • Definition of biodiversity • Levels of biodiversity • Geographical distribution of biodiversity • Evolution and biodiversity • Human impact on bio- and landscape diversity

Bio- and landscape diversity: Theme # 2 Definition of biodiversity "Biological diversity" or "biodiversity" has many interpretations. The term “biological diversity” was first used in 1968 by wildlife scientist and conservationist Raymond F. Dasmann in his book titled “A Different Kind of Country” advocating nature conservation. However the word was not widely used until 1980 -s. Thomas E. Lovejoy in late 1970 -s introduced the word “biological diversity” to the wider conservation and science communities using it not just as a word but as a scientific concept. In 1985 W. G. Rosen, used the term's contracted form “biodiversity”: biodiversity=biological diversity Bruce A. Wilcox in 1982 in the World National Parks Conference in Bali defined the biological diversity as the variety of life forms. . . at all levels of biological systems (i. e. , molecular, organismic, population, species and ecosystem). . . “ The 1992 United Nations Earth Summit in Rio de Janeiro defined biological diversity as "the variability among living organisms from all sources, including, 'inter alia', terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems". ecosystems This definition of biodiversity is legally accepted, since it is the definition adopted by the United Nations Convention on Biological Diversity. Biodiversity has been seen as the total (and irreducible) complexity of all life, including not only the great variety of organisms but also their varying behavior and interactions.

Bio- and landscape diversity: Theme # 2 Biodiversity and Diversity While speaking about the biodiversity (not the diversity itself) we mean first of all the ability of organisms (populations, communities, ecosystems) to survive in future, to contribute to life, to maintain life in our planet. The diversity itself (with no connection to biology and life) measures how different, numerous, complex the collection of certain objects or events are. Imagine the island where only male (or only women) are living. They could be very different – tall and small, white and black, young and old, clever and stupid. BUT all of them are men. They never produce a spring (new generation, born children). Such population will extinct (die) very quickly. The same is true for most biological populations. It could be diverse in many respects but if its gender structure is simple and unbalanced, the population will never survive. Or if the age structure of population would be simple – all individuals are in their old age and are not able to reproduce new generation – the population would extinct (die) very soon. Gender structure of a population is important. Age structure of population is important too. If the population consists of old individuals only it will not survive because would hardly produce spring (children, new generation) Geographic (spatial) pattern of species and communities is important as well. To survive species need to occupy the area of a particular size. If this size of the area populated by the species is too small individuals will became close relatives (the effect of inbreeding). They would hardly produce vital generation and will extinct quickly. Biodiversity is not simply the diversity of organisms or their features. It is the diversity of life.

Bio- and landscape diversity: Theme # 2 Levels of biodiversity When studying or protecting the biodiversity one could ask: diversity of what? What biological objects are considered while studying and protecting the biodiversity? Are they various organs of an organism, organism itself, or their ensembles? Biologists agree that there at least five levels at which biological variety is identified: – genetic diversity – species (population) diversity – community diversity – ecosystem diversity – landscape diversity These are traditional levels of biodiversity. However one could identify some other levels. For example, professor Anthony Campbell at Cardiff University, UK has defined the level of molecular diversity. Many biogeographers compare the biodiversity of various ecological regions, continents, river basins and other regions and say about the regional biodiversity. One may say also about the diversity of life and landscapes on a global level. It is especially useful while comparing the state and structure of biosphere of different geological epochs. Therefore the global biodiversity also could be discussed.

Biodiversity: Theme # 2 Levels of biodiversity: genetic diversity Genetic diversity is the degree of variability of the genetic material of an organisms of the same species. High genetic diversity within the population (between the individuals of the same species) indicates populations that can more easily adapt to changing situations and environments, and also a greater assortment of materials that can be found, increasing the chances of finding a useful compound. Low genetic diversity is dangerous for populations mainly because of two facts: 1 - the individuals could not produce viable spring (new generation) and will quickly extinct due to the inbreeding (all individuals of the population are in fact close relatives and they could born a child of a decreased fitness (not healthy) or could not produce any child at all; 2 – population with low genetic diversity could hardly adopt to new environments and will extinct if the natural conditions will change (for example due to climatic changes) Assessment of genetic diversity is both time-consuming and expensive, requiring modern laboratories and expensive chemicals. Inbreeding is a genetic term that refers to reproduction as a result of the mating of two animals which are genetically related to each other. If the relationship is a close, inbreeding can increase the chances of offspring being affected by recessive or deleterious traits. This generally leads to a decreased fitness of a population, which is called inbreeding depression.

Biodiversity: Theme # 2 Levels of biodiversity: species diversity Species diversity is determined by the number and percentage distribution of species within the community. The bigger the number of species is the higher species diversity would be. The distribution of species is also important factor contributing to high species diversity of the community. The number of species Two species – low diversity. Six species – high (rich) diversity. The distribution of species Two species: one is dominant, another is represented with one or few individuals – low diversity. Two species both having relatively equal proportion of the number of individuals in the community– high (rich) diversity.

Biodiversity: Theme # 2 Levels of biodiversity: higher taxon diversity In case of some groups of organisms the numbers of species is so large that it is not practical to identify them all. For example, fully half of the 1. 5 million identified organisms are insects. Furthermore, species of many microorganisms have not yet been identified or named. Only identification to higher taxonomic groups may be possible. In cases where the species could hardly be identified and if the species within the higher taxonomic groups live in similar habitats, have similar lifestyles etc the biodiversity is determined not for species but for higher taxonomic groups – most often for the genus or family level,

Biodiversity: Theme # 2 Levels of biodiversity: community diversity A biological community is an association or assemblage of populations of organisms whose composition, dynamics and other features are determined by the properties of the environment and by the relations of the organisms to each other. In simpler words, a community is an assemblage of populations living within one area or habitat. The difference between population and community: a population is an assemblage of individuals all belonging to one species, while a community is an assemblage of few populations Biological population = assemblage of organisms of one species Biological community = assemblage of populations Ecosystem = biological community with its environment Community diversity relates to a composition of species within a community. It depends on number of species in a community and on a proportion (relative representation) of species in a community. The number of species in a community is called species richness and the relative representation of species is called abundance. Species richness and abundance are two basic components of a community diversity. Community diversity = function of species richness and abundance

Biodiversity: Theme # 2 Levels of biodiversity: ecosystem diversity An ecosystem is a biological community of interdependent organisms together with the environment that they inhabit and with which they interact. Central to the concept of ecosystem is the idea that living organisms (plants, animals, and microorganisms) interact with every other element in their local environment. Ecosystem is a complex composed with the biotic communities, soils, climate, waters, air. They all are closely related and are depended on each other. The diversity of ecosystem is the variety and complexity of the relations between its elements. Normally simple ecosystems are not stable while ecosystems having high diversity has higher stability both to changes in the natural environment and to human influences. The concept of ecosystem The diversity of ecosystem is the variety and complexity of the relations between the elements composing the ecosystem. . The diversity of an ecosystem is dependent on: Ш physical characteristics of the environment, the Ш diversity of species in ecosystem the Ш interactions that the species have with each other and with the environment. the

Bio- and landscape diversity: Theme # 2 Levels of biodiversity: landscape diversity There exist two understandings of the landscape diversity: bioecological and geographical. Bioecological interpretation of landscape diversity: Most ecologists and biologists consider landscape diversity as a highest level of biodiversity defining it as the diversity of ecosystems composing the landscape. In such understanding the landscape diversity depends mostly on the number of ecosystems within the landscape, their spatial pattern and configuration. Few ecosystems – low landscape diversity. Geographical interpretation of landscape diversity is supported mainly be the scientists and experts with the geographical background. They believe that the landscape diversity is much more complex phenomenon than just a particular level of biodiversity and includes not only the diversity of living (biotic) elements but abiotic (physical) as well. Moreover they say that the landscape diversity is the basis for biodiversity on its various levels, as the diversity of landscape creates (or limits) the possibilities for flourishing the life. The concept of landscape diversity was well known to landscape ecologists since at least 1970 -es, but in the international legislative documents it was first defined in the Pan-European Biological and Landscape Diversity Strategy in 1995. Many ecosystems – high landscape diversity. The Pan-European Biological and Landscape Diversity Strategy is the adaptation of the Convention on Biological Diversity for Europe. It was adopted at the 3 rd Ministerial Conference "An Environment for Europe" held in October 1995 in Sofia, Bulgaria. The strategy differs from previous attempts to conserve biodiversity in at least two important ways: Ø it has a vast geographical scope, covering virtually the entire continent of Europe; Ø it stresses on the need for protection of environments (landscapes and ecosystems), rather than protecting only threatened species or a limited number of valuable sites. .

Bio- and landscape diversity: Theme # 2 Levels of biodiversity: landscape diversity Landscape diversity often becomes lower if the land is used improperly. In most cases it leads to the degradation of landscape and it could be used anymore for agriculture, forestry or for other human purposes.

Bio- and landscape diversity: Theme # 2 Values of biodiversity The issue about the values of biodiversity is in fact the issue why should we study and protect the biodiversity? Why is it really important? and for whom is it important? Arguments for protecting biodiversity fall into two categories of its values: intrinsic values and anthropocentric values. Intrinsic values of biodiversity – all the life forms in the Earth (plants, animals, microorganisms) are valuable themselves. They should be protected regardless of its value to humans. We are responsible for not our life only but for the life of any other living creatures. This argument focuses on the conservation of all species. Protection of biodiversity is needed for biodiversity Anthropocentric values of biodiversity – Biodiversity provides countless benefits (services) to humans. Some of these benefits include: Ш Economic benefits (forestry, agriculture etc) Ш Human health benefits (drugs and medicines made from plants, microorganisms etc; recreation in nature) Ш Aesthetic benefits Ш Scientific knowledge Ш Keeping environment suitable for human living Ш Insurance against the future Protection of biodiversity is needed for humans

Bio- and landscape diversity: Theme # 2 Geographical distribution of biodiversity Biodiversity is not distributed evenly on Earth. The diversity of flora and fauna, ecosystems and landscapes depends on climate, altitude, soils, the presence of other species, and on human activities. It is richer in the tropics while in polar regions we may find fewer species. Generally, the biodiversity declines from the equator to the poles in terrestrial regions. However, for oceans this tendency is not proven and there are several cases where diversity in high latitudes (closer to the poles) actually increases. Amazon tropical rainforest in Brazil Mammals diversity with distance from the Equator A biodiversity hotspot is a region with a high level of endemic species and rich biodiversity. For example, Brazil's Atlantic Forest is considered a hotspot of biodiversity and contains roughly 20, 000 plant species, 1350 vertebrates, and millions of insects, about half of which occur nowhere else in the world. Dense human habitation tends to occur near hotspots. Most hotspots are located in the tropics and most of them are forests.

Bio- and landscape diversity: Theme # 2 Geographical distribution of biodiversity Mapping of biodiversity (composing the maps of biodiversity) is important because it allows to find out the areas where the biodiversity is especially rich (needs to be protected) and the areas where it is low (needs to be restored and enriched)

Bio- and landscape diversity: Theme # 2 Evolution and biodiversity Biodiversity is the result of 3. 5 billion years of evolution. The history of biodiversity during the last 540 million years (Phanerozoic geological era) starts with rapid growth during the Cambrian explosion – a period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so global diversity showed l overall trend, but was marked by periodic, massive losses of diversity classified as mass extinction events. Most biologists agree that the period since the emergence of humans is part of a new mass species extinction, the Holocene extinction event. This event is caused primarily by the impact of humans on natural environment. The present rate of extinction is sufficient to eliminate most species on the planet Earth within 100 years

Bio- and landscape diversity: Theme # 2 Evolution and biodiversity Jack Sepkoski and David Raup : "Big Five" mass extinctions: 1 - Ordovician-Silurian extinction event 440 -450 million years ago at the Ordovician-Silurian transition. Two events occurred that killed off 27% of all families and 57% of all genera. It is the second largest of the five major extinctions in Earth's history in terms of percentage of genera that went extinct. 2 - Late Devonian extinction event 360 -375 Ma near the Devonian-Carboniferous transition. At later parts of the Devonian Period, a prolonged series of extinctions eliminated about 19% of all families, 50% of all genera and 70% of all species. 3 - Permain-Triassic extinction event - 251 Ma is the Earth's largest extinction killed 57% of all families and 83% of all genera (53% of marine families, 84% of marine genera, about 96% of all marine species and an estimated 70% of land species) including vertebrates, insects and plants. The "Great Dying" had enormous evolutionary significance: on land, it ended the primacy of mammal-like reptiles. The recovery of vertebrates took 30 million years. 4 - Triassic-Jurassic extinction event - 205 Ma; about 23% of all families and 48% of all genera (20% of marine families and 55% of marine genera) went extinct. Most non-dinosaurian archsaurs, most therapsids, and most of the large amphibians were eliminated, leaving dinosaurus with little terrestrial competition. 5 – End Cretaceous-tertiary extinction event (K-T extinction) - 65 Ma ago; about 17% of all families, 50% of all genera and 75% of species went extinct. It ended the reign of dinosaurus and opened the way for mammals and birds to become the dominant land vertebrates. In the seas it reduced the percentage of sessile (fixed to a place) animals to about 33%.

Bio- and landscape diversity: Theme # 2 Human impact on biodiversity Most of the species extinctions from 1000 AD to 2000 AD are due to human activities, in particular destruction of plant and animal habitats. The rate of species loss is greater now than at any time in human history, with extinctions occurring at rates hundreds of times higher than background extinction rates. 30% of all natural species will be extinct by 2050. Of these, about one eighth of the known plant species are threatened with extinction. Some estimates put the loss at up to 140, 000 species per year. (based on Species-area theory) and subject to discussion. The decrease of the Living Planet Index (the measure of state of global biodiversity) Loss of old growth forest in the United States

Bio- and landscape diversity: Theme # 2 Human impact on biodiversity The factors that threaten biodiversity have been variously categorized. Edward O. Wilson introduced the acronym HIPPO, standing for Habitat destruction, Invasive species, Pollution, Human Over Population, and Overharvesting. The most authoritative is the IUCN’s Classification of Direct Threats adopted by most major international conservation organizations 1 Residential & Commercial Development Threats from human settlements or other non-agricultural land uses with a substantial footprint 2 Agriculture & Aquaculture 3 Energy Production & Mining Threats from production of non-biological resources 4 Transportation & Service Corridors Threats from long narrow transport corridors and the vehicles that use them including associated wildlife mortality 5 Biological Resource Use Threats from Hunting, Gathering Terrestrial Plants, Harvesting plants and other non-animal products for commercial, recreation, and other purposes. 6 Human Intrusions & Disturbance Threats from human activities that alter, destroy and disturb habitats and species (Recreational Activities, War & Military Exercises, Work & Other Activities 7 Natural System Modifications Threats from actions that convert or degrade habitat often to improve human welfare (Dams & Water Management, Fire Control etc) 8 Invasive Species and Introduced Genetic Material Threats from non-native and native plants, animals, pathogens/microbes, or genetic materials that have or are predicted to have harmful effects on biodiversity following their introduction, spread and/or increase in abundance 9 Pollution 10 Geological Events Threats from catastrophic geological events 11 Climate Change Threats from long-term climatic changes

Bio- and landscape diversity: Theme # 2 Next theme: Values and functions of biodiversity • Intrinsic values • Anthropocentric values • How to assess the values of biodiversity

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