TEMPORAL TRENDS OF HEAVY METAL CONCENTRATIONS IN BROWN MACROALGAE FROM COASTAL ENVIRONMENTS

García-Seoane, Rita; Aboal, Jesús Ramón; Pacín, Carme; Varela, Zulema; González, Aridane; Fernández, José Ángel

TEMPORAL TRENDS OF HEAVY METAL CONCENTRATIONS IN BROWN MACROALGAE FROM COASTAL ENVIRONMENTS

García-Seoane, Rita,Aboal, Jesús Ramón,Pacín, Carme,Varela, Zulema,González, Aridane,Fernández, José Ángel

Repository: digital.csic.es
Language: en

Abstract

Heavy metals are one of the major drivers of ecological changes in coastal ecosystems. Macroalgae are primary producers of great relevance for ecosystem structure and functioning in these environments, and play a key role in the trophic transfer of these contaminants in the food web. Here, we present the most extensive assessment until now (>3500 records) of heavy metal concentrations in brown macroalgae (Class Phaeophyceae) sampled between 1933 and 2020 worldwide. The study compiles this information from 420 peer reviewed articles to be used as a proxy of global long-term changes in metal concentrations. We report the first detailed multi-decadal time series of Cd, Co, Cr, Cu, Fe, Hg, Mn, Pb and Zn in algae using generalized additive models (GAMs), confirming a significant decrease in metal contamination in the world’s coastal environments since ca. the 1970s for Pb (84% reduction), Zn (79%), Cd (77%) and Cu (72%), since the 1980s for Mn (75%) and Hg (65%), and since the 1990s for Cr (66%), Fe (64%) and Co (60%). Important environmental consequences for the whole aquatic ecosystem, even for human health, may be expected from these changes. The present results provide a building block for the overall evaluation of the status and trends of marine metal contamination, and will help researchers and policy makers to promote new legal regulations and environmental goals against pollution.

Full text

TEMPORAL TRENDS OF HEAVY METAL CONCENTRATIONS IN BROWN MACROALGAE FROM COASTAL ENVIRONMENTS Ga cía-Seoane, R1, Aboal, JR2, Pacín, C2, Va ela, Z2, González, A3, Fe nández, JA2 1Cen o Oceanog á ico de A Co uña, Ins i u o Español de Oceanog a ía (IEO). 2CRETUS. Ecology Sec ion. Uni e sidade de San iago de Compos ela (USC). 3Ins i u o Uni e si a io de Oceanog a ía y Cambio Global (Iocag). Uni e sidad de Las Palmas de G an Cana ia. Con ac : [email p o ec ed]s / i aga ciaseoa[email p o ec ed] PSA 2021 Vi ual Mee ing INTRODUCTION Me allic con amina ion is one o he mos impo an d i e s o global change in ecosys ems wo ldwide. Especially since he indus ial e olu ion, hea y me als and me alloids ha e been in ensi ely discha ged o he ma ine en i onmen by human ac i i ies wi hou adequa e en i onmen al con ol. Mac oalgae a e p ima y p oduce s o g ea ele ance o ecosys em s uc u e and unc ioning in hese en i onmen s, and play a key ole in he ophic ans e o hese con aminan s ac oss he ood web. B own mac oalgae (Class Phaeophyceae) ha e been ex ensi ely used in mul i ude o esea ch s udies moni o ing hea y me als wo ldwide because hei abili y o in eg a e high le els o con aminan s om he en i onmen . Only ew li e a u e sou ces ha e epo ed empo al ends in me al concen a ions in b own mac oalgae. Al hough es ic ed o sho - e m egionally ci cumsc ibed se ies, some o hese s udies (i.e. Viana e al., 2010; Ga cía-Seoane e al., 2021) ha e obse ed a dec easing in me al concen a ions in mac oalgae since he beginning o he XXI cen u y in a small egion o he No h A lan ic Ocean coas . OBJECTIVE To de e mine whe he hese ends in he dec ease o hea y me als in b own mac oalgae a e es ic ed o ha small egion du ing he pas wo decades o sp ead o o he a eas o he plane and p e ious imes, while assessing he e ec i eness o en i onmen al policies implemen ed o e ime. METHODOLOGY The s udy compiles in o ma ion (>3500 eco ds, om 420 pee e iewed a icles) o hea y me al concen a ions in b own mac oalgae sampled be ween 1933 and 2020 wo ldwide. De ailed mul i-decadal ime se ies o Cd, Co, C , Cu, Fe, Hg, Mn, Pb and Zn in di e en b own algae amilies a e epo ed using gene alized addi i e models (GAMs) unned in R s a is ical so wa e. PRELIMINARY RESULTS CONCLUSIONS Table 1. Va ia ion in me al concen a ions p edic ed by GAMs models. Signi ican dec eases a e shown in bold ype. Fig. 1. Long- e m empo al changes in Pb concen a ions (log, µg g-1)in di e en b own mac oalgae amilies. Black solid line: GAM adjus . G ey a ea:95% con idence in e al in he GAM adjus . Do s: a eas wi h (pu ple) and wi hou (g een) an h opogenic p essu e. Maps co espond o he main a ea o dis ibu ion o each amily in he compiled da ase . These esul s con i m a widesp ead change in he le els o me als a ec ing a subs an ial pa o he coas al en i onmen s in he globe. I seems ha some ecosys ems a e esponding posi i ely o he en i onmen al policies implemen ed in ecen decades agains ma ine con amina ion. Impo an en i onmen al consequences o he whole aqua ic ecosys em, e en o human heal h, may be expec ed om hese changes. Acknowledgemen s: J.R. Aboal, C. Pacín, Z. Va ela and J.A. Fe nández belong o he Galician Compe i i e Resea ch G oup GRC/GPC2016-002. R. Ga cía-Seoane is suppo ed by he Juan de la Cie a-Fo mación p og am (Spanish Minis y o Science and Inno a ion; FJC2019-040921-I). Re e ences: - Viana e al. (2010). Wa e Res. 44 (6), 1713-1724. - Ga cía-Seoane e al. (2021). J. Haz. Ma . 412,125268. We obse e a signi ican dec ease in me al con amina ion in he wo ld’s coas al en i onmen s in he ange o -44.9 o -95.9%, s a ing in he la e 1960s and ea ly 1970s o Cd, Cu, Pb and Zn, and la e 1980s and ea ly 1990s o Co, C , Fe, Hg and Mn,and con inuing o e he las 50 yea s. See Pb in Fig. 1 as an example. Annual a es o dec ease (ca. -2%), we e ai ly consis en ac oss elemen s and amilies, al hough Dyc io aceae eached he highes a es ( om o e -3 o -6%). See Table 1 o mo e de ails.