Biodiversity. University of Debrecen, Faculty of Science and Technology István Bácsi PhD

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1 Biodiversity University of Debrecen, Faculty of Science and Technology István Bácsi PhD

2 Biodiversity is the variety of different types of life found on Earth and the variations within species. It is a measure of the variety of organisms present in different ecosystems. This can refer to genetic variation, ecosystem variation, or species variation (number of species) within an area, biome, or the whole planet.

3 1. Measuring of diversity A diversity index is a quantitative measure that reflects how many different types (such as species) there are in a dataset, and simultaneously takes into account how evenly the basic entities (such as individuals) are distributed among those types. The value of a diversity index increases both when the number of types increases and when evenness increases. For a given number of types, the value of a diversity index is maximized when all types are equally abundant. - Diversity at species level - All kind of indices try to characterise the correlation of S : N (species number : number of individuals) Shannon-Wiener index (H) One of the most often used indices. Sobs i 1 where: p i log e p i p i relative abundance (proportion) of the species belonging to the ith type.

4 Simpson-Yule index (D) or quadratic diversity It describes what is the probability that the second sampled individual belongs to the same species as the first. C S obs i p 2 i where p 2 i N N i T 2 and the index itself: D 1 C N i number of individuals belonging to the ith species N T total individual number of the sample

5 Berger-Parker dominancy index It compares the proportion of the dominant species to the total number of individuals. d N max N T N max individual number of the dominant species Evenness - Diversity is maximal, when all species of a community are equally abundant. Evenness can express the similarity between the observed diversity and the possible maximal diversity at the given species number. - A modified version of the index also takes into accont the possible maximum (D max ) and minimum (D min ) values of diversity.

6 E H D D max D D min min For example, if we use Shannon-Wiener index: D min = 0, D max = log(s), where log(s) is to total number of taxa, so: E H H log S

7 The Convention on Biological Diversity has been signed on 13th june, 1992 in Rio de Janeiro at the conference of Environment and Progression of UN. The first biodiversity day has been held on 22nd may, 2006 in Hungary. Natural forest Planted forest

8 2. Factors leading to biodiversity loss (or alter biodiversity) 2.1. Extinction Number of species on Earth

9 Great extinctions in the history of Earth

10 Nature transforming and destructive activities of mankind are increasing. Unfortunately, extinction rate of species also accelerated. The most accurate data on the rate of species extinction are for the birds and mammals (the number of extinct mammals is 85, birds 113 from the 1600s to present day). A quarter of terrestrial species, 28% of marine species and 29% of freshwater species extinct from 1970 to 2005 according to the WWF (World Wide Fund for Nature). Biodiversity decreased with a 35% on Earth in the previous 35 years. Species died out because of human activities (mainly hunting):

11 Dodo (Raphus cucullatus) Thylacine (Thylacinus cynocephalus) Giant alka (Pinguinus impennis) Quagga (Equus quagga quagga)

12 2.2. Habitat degradation and destruction Only 15% of lands remained in its original state in Europe. Surface coverage categories in Hungary. Artificial surface Field Meadow, pasture Grape Fruit trees Forest Reeds Other agricultural area Other half-natural area Surface water

13 2.3. Appearance of foreign (alien) species - plants Invading (invasive) species in a sandy grassland: Alianthus ( tree of heaven ) in front, milkweed behind them, and acacia in the background (location: Soltszentimre).

14 2.3. Appearance of foreign (alien) species animals (molluscs) Spanish slug (Arion lusitanicus) Eastern Asiatic Clam (Sinanodonta (Anodonta) woodiana) Zebra Clam (Dreissena polimorpha)

15 2.3. Appearance of foreign (alien) species animals (fishes) Black bullhead (Ameiurus melas) Amuri kagyló (Anodonta woodiana) Pumpkinseed (Lepomis gibbosus) Chinese sleeper or Amur sleeper (Perccottus glenii)

16 2.3. Appearance of foreign (alien) species animals (reptiles) Common snapping turtle (Chelydra serpentina) Pond slider (Trachemys scripta)

17 2.3. Appearance of foreign (alien) species animals (insects) Harlequin ladybird (Harmonia axyridis) First appearance in Hungary: February, 2008 Boxtreemoth(Cydalima perspectalis) First appearance in Hungary: 2011 Spotted-wing vinegar fly First appearance in Hungary: Autumn, 2012 (Drosophila suzukii)

18 2.4. Hunting and trade They have a role both in extinction of species and in settling and spreading of new species. Raccoon (Procyon lotor) Mouflon (Ovis aries orientalis)

19 2.5. Genetic manipulation During genetic engineering genes of one species are transferred to another species genome, thus genetically modified organisms are created. The method is most widespread in plant breeding.

20 Genetic modification or genetic engineering In general, with the example of pest-resistant maize

21 Genetically modified bacteria

22 Genetically modified plants Bacteria as vectors

23 Viruses as vectors

24 Possibility

25 3. Protection of biodiversity - Protection of species - Protection of habitats - Local scale (corridors, buffer zones are necessary) - Regional scale Old World swallowtail (Papilio machaon) Great bustard (Otis tarda) Scarce swallowtail (Iphiclides podalirius)

26 Nature reserves in Hungary:

27 Thank You for Your attention!