Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Holocene phototrophic community and anoxia dynamics in meromictic Lake Jaczno (NE Poland) using high-resolution hyperspectral imaging and HPLC data |
| Abstract | Global spread of hypoxia and less frequent mixing in lakes is a major growing environmental concern. Climate change and human impact are expected to increasingly deteriorate aquatic ecosystems. The study of processes and drivers of such changes in the past provides a great asset for prevention and remediation in the future. We used a multiproxy approach combining high-resolution bulk pigment data measured by hyperspectral imaging (HSI) with lower-resolution specific chlorophyll types and carotenoids measured by HPLC to examine Holocene trophic state changes and anoxia evolution in the meromictic Lake Jaczno, NE Poland. A redundancy analysis (RDA) including pollen-inferred vegetation cover, temperature and human impacts provides insight into specific conditions and drivers of changing trophic and redox states in the lake. Anoxic and sulfidic conditions were established in Lake Jaczno after initial basin infilling 9500 years ago. Until 6700 cal BP, lake trophy was relatively low, water turbidity was high and green sulfur bacteria (GSB) were abundant within the phototrophic community, suggesting a deep oxic-anoxic boundary and weak stratification. The period between 6700-500 cal BP is characterized by constantly increasing lake production and a gradual shift from GSB to purple sulfur bacteria (PSB), suggesting a shallower oxic-anoxic boundary and pronounced stratification. Yet, the presence of spheroidene and speroidenone in the sediments indicates intermittent anoxia. After 500 cal BP, increasing human impact, deforestation and intensive agriculture promoted lake eutrophication, with a shift to PSB dominance and establishment of permanent anoxia and meromixis. Our study unambiguously documents the legacy of human impact on processes determining eutrophication and anoxia. |
| Source | Biogeosciences (Print) 18 (5), pp. 1839–1856 |
| Keywords | PaleolimnologyAnoxiaMeromixisVarved sedimentsNorth-East EuropeHoloceneHuman impactsedimentary pigment |
| Journal | Biogeosciences (Print) |
| Editor | Copernicus Publ., Göttingen, Germania |
| Year | 2021 |
| Type | Articolo in rivista |
| DOI | 10.5194/bg-18-1839-2021 |
| Authors | Makri, Stamatina; Lami, Andrea; Tu, Luyao; Tylmann, Wojciech; Vogel, Hendrik; Grosjean, Martin |
| Text | 454290 2021 10.5194/bg 18 1839 2021 Scopus 2 s2.0 85102823588 Paleolimnology Anoxia Meromixis Varved sediments North East Europe Holocene Human impact sedimentary pigment Holocene phototrophic community and anoxia dynamics in meromictic Lake Jaczno NE Poland using high resolution hyperspectral imaging and HPLC data Makri, Stamatina; Lami, Andrea; Tu, Luyao; Tylmann, Wojciech; Vogel, Hendrik; Grosjean, Martin Uniwersytet Gdanski; Consiglio Nazionale delle Ricerche; University of Bern Global spread of hypoxia and less frequent mixing in lakes is a major growing environmental concern. Climate change and human impact are expected to increasingly deteriorate aquatic ecosystems. The study of processes and drivers of such changes in the past provides a great asset for prevention and remediation in the future. We used a multiproxy approach combining high resolution bulk pigment data measured by hyperspectral imaging HSI with lower resolution specific chlorophyll types and carotenoids measured by HPLC to examine Holocene trophic state changes and anoxia evolution in the meromictic Lake Jaczno, NE Poland. A redundancy analysis RDA including pollen inferred vegetation cover, temperature and human impacts provides insight into specific conditions and drivers of changing trophic and redox states in the lake. Anoxic and sulfidic conditions were established in Lake Jaczno after initial basin infilling 9500 years ago. Until 6700 cal BP, lake trophy was relatively low, water turbidity was high and green sulfur bacteria GSB were abundant within the phototrophic community, suggesting a deep oxic anoxic boundary and weak stratification. The period between 6700 500 cal BP is characterized by constantly increasing lake production and a gradual shift from GSB to purple sulfur bacteria PSB , suggesting a shallower oxic anoxic boundary and pronounced stratification. Yet, the presence of spheroidene and speroidenone in the sediments indicates intermittent anoxia. After 500 cal BP, increasing human impact, deforestation and intensive agriculture promoted lake eutrophication, with a shift to PSB dominance and establishment of permanent anoxia and meromixis. Our study unambiguously documents the legacy of human impact on processes determining eutrophication and anoxia. 18 Published version http //www.scopus.com/record/display.url eid=2 s2.0 85102823588 origin=inward Makri et al. 2020 Holocene phototrophic community and anoxia dynamic.pdf versione pdf Makri et al. 2020 Holocene phototrophic community and anoxia dynamic.pdf Articolo in rivista Copernicus Publ. 1726 4170 Biogeosciences Print Biogeosciences Print Biogeosciences Print Biogeosciences. Print BG Print Print andrea.lami LAMI ANDREA |