METHODS FOR MEASUREMENT AND VISUALIZATION OF CHANGES IN BIODIVERSITY

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1 Proceedngs of ECOpole Vol. 5, No. 20 Marola CHOMCZYŃSKA, Grzegorz ŁAGÓD, Agneszka MONTUSIEWICZ and Jacek MALICKI METHODS FOR MEASUREMENT AND VISUALIZATION OF CHANGES IN BIODIVERSITY METODY POMIARU I WIZUALIZACJI ZMIAN BIORÓŻNORODNOŚCI Abstract: Bodversty can be evaluated basng on the speces numbers or numbers of chosen taxa (S). The bodversty assessment s also enabled usng the Shannon ndex (H) that ncludes numbers of taxa and ther relatve abundances (or relatve bomass lkely relatve degrees of coverng). The proper descrpton of bologcal or statstcally sgnfcant dfferences (or ther absence) between the compared taxocenoss of dentcal or subjectvely dfferent values of S and H, s not possble by use of both methods mentoned. Thus, the am of our work was to present the manners for solvng these problems basng on the example of three hypothetcal organsm communtes. Two of the communtes mentoned were characterzed by the same values of S (taxon rchness) and dfferent values of H (the Shannon ndex) and two ones had smlar H values and dfferent values of S. To obtan the complete descrpton of bologcal dfferences between compared communtes the followng ndces were calculated: H max (a maxmum value of Shannon ndex for the rchness of taxa represented by the same number of ndvduals), V d (a percentage value of coverng structural capacty of communty, evenness defcency ), E (MacArthur ndex - a taxon number (S) n a communty for whch the observed value of H equals H max) and P s (taxon rchness shortage n percents). Moreover, graphcal method of β, profles was used for comparng communty dverstes. Instead, to obtan nformaton about statstcally sgnfcant dfferences n bodversty between analyzed communtes, the rarefacton curves were appled. The curves are based on the zero models and the Monte Carlo method. Keywords: bodversty, Shannon ndex, rarefacton curves, profle method Whle undertakng the strategy of protecton and ratonal usage of bologcal dversty [], an deal soluton would be the formaton of condtons enablng the control of strategy to be realzed, where the montorng, e systematc measurements, would be performed, therefore the results of the measurements relably compared. Bodversty (bologcal dversty α, β, and γ) may be evaluated based on the rchness of speces S, or taxa selected at own preference [2]. It may also be assessed wth consderaton of the number of taxa and ther relatve abundance (or relatve bomass, or relatve coverage degree) by calculatng Shannon s ndex of dversty H. Whle applyng both methods, t s not possble to determne correctly the bologcal or statstcally sgnfcant dfferences (or the lack of such dfferences) between the compared taxocenoses of dentcal or subjectvely dfferent S and H values. Hence, the objectve of the presented study s to demonstrate methods of solvng ths problem, whch can possbly be adopted. Materals and methods The materal used for the study were three hypothetcal communtes, two of whch had the same values S (speces rchness), but dffered wth respect to the H values (Shannon s ndex), and two possessed smlar H values but dffered by S values; for better llustraton of the problem - they had the same number of ndvduals N = 20 (Tab. ). Faculty of Envronmental Engneerng, Lubln Unversty of Technology, ul. Nadbystrzycka 40B, Lubln, phone , emal: M.Chomczynska@ws.pol.lubln.pl

2 30 Marola Chomczyńska, Grzegorz Łagód, Agneszka Montusewcz and Jacek Malck Taxonomc-bocenotc characterstcs of three hypothetcal communtes A, B and C Taxa Communty A B C s n n n a b 4 6 c d e Table The below-mentoned formulas were appled to perform measurements and comparsons of bologcal dversty of the communtes (objects) charactersed [3-5]: s S = () = S = s N = (2) n n = (3) N Π S H' = Π lg Π (4) = 2 H' = max lg2s (5) H' Vd = 00 H' (6) max H' E = 2 (7) E P s = 00 (8) S where: S - speces rchness, number of taxa; s - dstngushed taxon; N - total number of ndvduals n the sample (total number of ndvduals n taxocenoss); n - number of ndvduals of th taxon; Π - relatve abundance of the th taxon; H - Shannon s ndex of bodversty; H max - maxmum H value for a gven rchness S, whch would occur f all taxa were equally abundant; V d - a percentage value of mplementaton of communty capacty (evenness defcency), E - speces rchness of communty, for whch the observed H s H max value; P s - expressed n percent speces shortage. Moreover, n order to compare the bodversty of communtes, a graphc profle method of β was appled [4]. The β profles were plotted based on the ponts on the coordnate axes (β, β ), where β > and β s descrbed by the followng formula: S β+ Π S β Π = β = Π = (9) β β =

3 Methods for measurement and vsualzaton of changes n bodversty 3 To obtan nformaton concernng the statstcally sgnfcant dfferences between the communtes analysed from the aspect of dversty of the taxa, null models were appled, whch are based on the Monte Carlo method [6, 7]. For the analysed communtes A, B and C calculatons were performed by means of the Eco Sm 7.0 software [6, 7], obtanng data necessary for plottng rarefacton curves. Results and dscusson Table 2 presents the results of calculatons performed accordng to the formulas ()-(4). Taxa rchness, total abundance and Shannon s ndex for communtes A, B, and C Table 2 Communty Index A B C S N H Based on the above-presented results, t s not possble to state unequvocally f the communtes compared, especally B and C, vary wth respect to the bologcal dfferences. However, based on the data contaned n Table 3, t may be presumed that n the bologcal sense communty C s poorer wth respect to bodversty than communty A, but rcher than communty B because t s charactersed by a lower evenness defcency V d and a lower speces shortage P s. Values of ndces H max, V d, E and P s for communtes A, B and C Table 3 Communty Index A B C H max V d 0.0% 7.2% 3.7% E P s 0.0% 24.2% 5% Fgure present the results of the applcaton of the profle method. It s worth explanng that β profles plotted for compared communtes show ther rankng accordng to three ndces: speces count S = S, Shannon s ndex and Smpson s ndex S s =. = Π 2 For the communtes consdered, based on the β profles t may be presumed that taxocenoss A s more dverse than taxocenoses B and C, whle the taxocenoses B and C cannot be compared due to the crossng courses of the profles (Fg. ).

4 32 Marola Chomczyńska, Grzegorz Łagód, Agneszka Montusewcz and Jacek Malck β Fg.. The β profles for communtes A, B and C Fg. 2. Rarefacton curves of Shannon s ndex H for communtes A, B and C

5 Methods for measurement and vsualzaton of changes n bodversty 33 The above-presented methods do not allow makng judgements concernng nether statstcal sgnfcance of the dfferences nor confdence ntervals - the latter, when they do not overlap, decde about the sgnfcance of the dfferences between the communtes compared. The problem dscussed may be solved based on the multple samplng methods. Usng these methods, the rarefacton curves were obtaned for the compared communtes A, B and C (Fg. 2). A low number of taxa and ndvduals causes a certan angularty of the graphs obtaned, whch should dsappear wth regard to more abundant samples N > 50. The H values obtaned wth the use of the EcoSm 7.0 software dffer from those lsted n Table 2, because the EcoSm software calculates Shannon s ndex usng a natural logarthm, whle the base-2 logarthm s commonly appled n the theory of computer scence. Hence, H (A) value s.6, and H (B) and H (C) obtans the value of.33. The present graphs were plotted wth the use of MS Excel 2007 software. The authors of the EcoSm software suggest the applcaton of the SgmaPlot or S-Plus software, whch enable more desred effects to be obtaned wth respect to the graphc llustraton of the calculatons performed [6-8]. The applcaton of Excel also provdes opportuntes of nterpretaton of the results; therefore, based on the results, t may be presumed that n the case of Shannon s speces dversty, taxocenoss A sgnfcantly dffers from taxocenoses B and C, whch do not dffer by the parameter dscussed. Summary and conclusons Analyss of the results allows for the followng conclusons: Bodversty may be expressed quanttatvely, and after performng ts measurements t s possble to compare taxocenoses and ther changes n tme functon wth respect to ths parameter. The rarefacton methods enable determnaton of the statstcal sgnfcance of the dfferences, or statstcal lack of the dfferences, between Shannon s ndex values for the compared communtes. Elaborate ndces - dervatves of the H ndex (especally V d and P s ) allow concludng about the sgnfcance of the bologcal dfferences, even when the values of the Shannon s H ndces are numercally smlar. The β profles servng the comparson of the values of speces rchness, Shannon s and Smpson s ndces n the nvestgated taxocenoses, have a basc shortcomng - the β values n the denomnator of the fracton have to pass by 0 value, whch from the pont of vew of arthmetc s nadmssble. Acknowledgement Ths work was supported by the Mnstry of Scence and Hgher Educaton of Poland, Grant No. 4949/B/T02/2008/34. References [] Andrzejewsk R. and Wegle A.: Bologcal dversty of Poland. Narodowy Fundusz Ochrony Środowska, Warszawa 2003 (n Polsh). [2] Whtaker R.H.: Evolutonal measurements of speces dversty. Taxonomy, 972, 2, [3] MacArthur R.H.: Patterns of dversty. Bol. Rev., 965, 40,

6 34 Marola Chomczyńska, Grzegorz Łagód, Agneszka Montusewcz and Jacek Malck [4] Gove I.H., Patl G.P., Swndel B.F. and Talle C.: Ecologcal dversty and forest management. [In:] Handbook of Statstc 2, Eds. G.P. Patl and C.R. Rao. Elsever Scence B.V., Amsterdam, London, New York, Tokyo 994, [5] Łagód G., Malck J., Chomczyńska M. and Montusewcz A.: Interpretaton of the results of wastewater qualty bomontorng usng saprobes. Envron. Eng. Sc., 2007, 24(7), [6] Błędzk L.A.: Method for comparng speces rchness and speces dversty. Part I. Boskop, 2007,, 8-22, (n Polsh). [7] Błędzk L.A.: Method for comparng speces rchness and speces dversty. Part II. Boskop, 2007, 2, 20-23, (n Polsh). [8] Gotell N.J. and Entsmnger G.L.: EcoSm: Null models software for ecology. Verson 7.0, Jercho: Ackuret Intellgence Inc. and Kesey-Bear, USA, METODY POMIARU I WIZUALIZACJI ZMIAN BIORÓŻNORODNOŚCI Wydzał Inżyner Środowska, Poltechnka Lubelska Abstrakt: Boróżnorodność można ocenać na podstawe lczby gatunków lub lczby dowolne wybranych taksonów (S). Ocenę boróżnorodnośc można równeż przeprowadzć za pomocą ndeksu Shannona (H), do oblczeń którego wykorzystuje sę lczbę taksonów oraz ch względne lczebnośc (lub względne bomasy ewentualne relatywne stopne pokryca). Przy użycu obu wymenonych metod ne można poprawne określć statystyczne stotnych czy też bologcznych różnc (lub ch braku) pomędzy porównywanym taksocenozam o dentycznych lub subektywne różnych wartoścach S H. Stąd celem prezentowanej pracy było przedstawene sposobów rozwązana tego problemu na przykładze trzech hpotetycznych zborowsk żywych organzmów. Wśród tych taksocenoz dwe charakteryzowały sę takm samym wartoścam S (bogactwa taksonów) różnym wartoścam H (ndeksu Shannona), a dwe mały zblżone wartośc H, a różne wartośc S. Dla pełnego określena różnc bologcznych pomędzy porównywanym zborowskam oblczono wskaźnk: H max (maksymalna wartość ndeksu Shannona dla danego bogactwa taksonów charakteryzujących sę takm samym lczebnoścam), V d (wyrażona w % wartość wypełnena strukturalnych możlwośc zborowska; nedostatek równomernośc ), E (ndeks MacArthura, czyl lczba taksonów S w zborowsku, dla którego dany ndeks H przyjąłby wartość maksymalną) oraz P s (wyrażony w % nedostatek bogactwa taksonów). Dodatkowo, dla porównana boróżnorodnośc zborowsk użyto grafcznej metody profl β. W celu uzyskana nformacj o statystyczne stotnych różncach mędzy analzowanym zborowskam pod względem boróżnorodnośc wykreślono krzywe rarefakcj, bazujące na modelach zerowych metodze Monte Carlo. Słowa kluczowe: boróżnorodność, ndeks Shannona, krzywe rarefakcj, metoda profl