Andrea Lami - Academia.edu (original) (raw)

Papers by Andrea Lami

Research paper thumbnail of Environmental changes in the Rila Mountains, Southwestern Bulgaria, as recorded by the sediments of a remote lake

Advances in Limnology, 2009

ABSTRACT Abstract: Chemical and biological sedimentary records of the high alpine lake “Bubreka”,... more ABSTRACT Abstract: Chemical and biological sedimentary records of the high alpine lake “Bubreka”, Rila Mountains, Bulgaria, were used to reconstruct palaeoecological conditions and to determine the phases in the ontogeny of the lake. Sediment cores taken in 2000 were dated by 210Pb and 137Cs and analysed for percentage of dry weight (%DW), loss-on-ignition (LOI), pigments, diatoms, chrysophyte stomatocysts, cladocerans, chironomids and spheroidal carbonaceous particles (SCPs). The studies on Lake Bubreka show that high mountain lakes are good sites for the study of the evolution and effects of the long range transport of atmospheric pollutants from the industrial lowlands to mountain regions. Four distinct successional phases can be described in the lake history during the last ~ 250 years, revealing complex interactions between anthropogenic impact and climate. Phase 1 (c. AD 1762-1834) is characterised by stable oligotrophical conditions. During Phase 2 (c. AD 1834 -1928) there is a change from oligotrophic to mesotrophic conditions. Phase 3 (c. AD 1928 - 1994 ± 2) shows an increase in LOI due to the high proportion of organic material. The shorter ice cover period in the lake may have created conditions more suitable for the growth of phyto- and zooplankton and changed the overall primary production from benthos to plankton. In Phase 4 (c. AD 1994 ± 2 - 2000) there is increased LOI, increasing percentages of periphytic diatoms, less favorable conditions for cladocerans, and rheophilic chironomid assemblages which indicate rapid input of nutrients causing mesotrophication. The SCP record and comparisons with other European mountain lakes suggest there is a moderate impact from atmospheric deposition compared with similar lakes elsewhere in Europe.

Research paper thumbnail of Sub-fossil pigments as a guide to the phytoplankton history of the acidified Lake Orta (N. Italy)

SIL Proceedings, 1922-2010, 1988

Research paper thumbnail of A Comparison of Constitutive and Inducible Non-Endogenous Keto-Carotenoids Biosynthesis in Synechocystis sp. PCC 6803

Microorganisms, 2019

The model cyanobacterium Synechocystis sp. PCC 6803 has gained significant attention as an altern... more The model cyanobacterium Synechocystis sp. PCC 6803 has gained significant attention as an alternative and sustainable source for biomass, biofuels and added-value compounds. The latter category includes keto-carotenoids, which are molecules largely employed in a wide spectrum of industrial applications in the food, feed, nutraceutical, cosmetic and pharmaceutical sectors. Keto-carotenoids are not naturally synthesized by Synechocystis, at least in any significant amounts, but their accumulation can be induced by metabolic engineering of the endogenous carotenoid biosynthetic pathway. In this study, the accumulation of the keto-carotenoids astaxanthin and canthaxanthin, resulting from the constitutive or temperature-inducible expression of the CrtW and CrtZ genes from Brevundimonas, is compared. The benefits and drawbacks of the two engineering approaches are discussed.

Research paper thumbnail of Preliminary results on palaeolimnology of the crater Lake Albano (Latium, Italy)

SIL Proceedings, 1922-2010, 1993

Research paper thumbnail of A multi-proxy analysis of climate impacts on the recent development of subarctic Lake Saanajärvi in Finnish Lapland

Journal of Paleolimnology, 2002

Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern... more Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern Finnish Lapland are studied by comparison of various biological and sedimentological proxies with the 200-year long climate record, specifically reconstructed for the site using a data-set of European-wide meteorological data. The multi-proxy evidence of simultaneously changing diatom, Cladocera, and chrysophyte assemblages along with the increased rates

Research paper thumbnail of Evidence for short-lived oscillations in the biological records from the sediments of Lago Albano (Central Italy) spanning the period ca. 28 to 17 k yr BP

Journal of Paleolimnology, 2000

We report the results of analyses of pigments (derived from algae and photosynthetic bacteria), d... more We report the results of analyses of pigments (derived from algae and photosynthetic bacteria), diatoms and invertebrate fossil remains (ostracods, cladocerans, chironomids) in two late Pleistocene sediment cores from Lago Albano, a crater lake in Central Italy. The record contains evidence for oscillations in lake biota throughout the period ca. 28 to 17 k yr BP. The earliest of these

Research paper thumbnail of Lacustrine organic matter and the Holocene paleoenvironmental record of Lake Albano (central Italy)

Journal of Paleolimnology, 2001

A combined bulk and detailed geochemical study of the sedimentary organic matter in Lake Albano, ... more A combined bulk and detailed geochemical study of the sedimentary organic matter in Lake Albano, central Italy, provides critical data to track the response of this aquatic system to the environmental changes of variable amplitude that occurred during the Holocene. Rock-Eval pyrolysis of this predominantly laminated, organic carbon-rich sedimentary sequence shows changes in hydrogen and oxygen indices that are related

Research paper thumbnail of Lake Redó ecosystem response to an increasing warming in the Pyrenees during the twentieth century

Journal of Paleolimnology, 2002

The ecosystem response of Lake Redó (Central Pyrenees) to fluctuations in seasonal air temperatur... more The ecosystem response of Lake Redó (Central Pyrenees) to fluctuations in seasonal air temperature during the last two centuries was investigated by comparison of reconstructed air temperatures with the sediment record. Fine slicing allowed a resolution of 3-6 years according to the 210 Pb dating, although it was still difficult to easily investigate the response to air temperature forcing, since extreme fluctuations in temperature occur on interannual timescales. However, the resolution was sufficient to show responses on decadal and century scales. An overall tendency to warming in mean annual temperature in the Central Pyrenees has been caused by summer and in particular by autumn increases. Many of the measured sediment variables apparently responded to these long term trends, but the significance of the relationships was highly conditioned by the structure of the data. The variables responding most on the finer time scales were the microfossils. For diatoms, chironomids and chrysophytes the main variability correlated to summer and to autumn temperatures. For two planktonic species, Fragilaria nanana and Cyclotella pseudostelligera, we found a link of their variability with temperature fluctuations in their growing months (September and October, respectively). This relationship appeared at a certain point during a general warming trend, indicating a threshold in the response. On the other hand, no significant changes in the dominant species could be linked to temperature, nor in any significant subgroup of the 180 diatom species present in the core. In contrast, for most chironomids (particularly Paratanytarsus austriacus, Heterotrissocladius marcidus and Micropsectra radialis) a negative relationship with summer temperature extended throughout the studied period. This response of the whole group gives chironomids a more robust role as indicators for recording temperature changes on long timescales (e.g., through the Holocene) and for lake signal inter-comparison. Finally, our results indicated that, in all cases, there was a significant resilience to high frequency changes and hysteresis despite extreme fluctuations. Although we were dealing with organisms with one or many generations per year, their populations seemed to follow the decadal trends in air temperature. Mountain Lake Research MOLAR This is the ninth of 11 papers published in this special issue on the palaeolimnology of remote mountain lakes in Europe resulting from the MOLAR project funded by the European Union. The guest editor was Richard W. Battarbee.

Research paper thumbnail of The environmental history of a mountain lake (Lago Paione Superiore, Central Alps, Italy) for the last c. 100 years: a multidisciplinary, palaeolimnological study

Journal of Paleolimnology, 1996

... main objectives of the AL:PE programme (Acidifica-tion of Mountain lakes: Palaeolimnology and... more ... main objectives of the AL:PE programme (Acidifica-tion of Mountain lakes: Palaeolimnology and Ecology, a project supported by the Commission of the European Community; Wathne & Patrick, 1994), of which the present study is one part. ...

Research paper thumbnail of Stratigraphy of specific algal and bacterial carotenoids in the sediments of Lake Varese (N. Italy)

Hydrobiologia, 1986

A study on the succession of some phytoplankton populations in the very eutrophic Lake Varese ove... more A study on the succession of some phytoplankton populations in the very eutrophic Lake Varese over the past 80–100 years, was based on thin-layer chromatography of four group-specific carotenoids (echinenone, lutein, myxoxanthophyll and oscillaxanthin). The development of diatoms was traced by microscope counts of their frustules. In addition, the carotenoid okenone, peculiar to some Chromatium species, was identified and related

Research paper thumbnail of The late Pleistocene ostracod record of the crater lake sediments from Lago di Albano (Central Italy): changes in trophic status, water level and climate

Journal of Paleolimnology, 1999

Four cores (ranging between ca. 9 and ca. 14 m in length) from Lago di Albano in Central Italy we... more Four cores (ranging between ca. 9 and ca. 14 m in length) from Lago di Albano in Central Italy were studied for their ostracod content, as well as algal and bacterial pigments, CaCO3 and concentration of organic matter. Cores PALB 94 1E and PALB 94 1C from Site 1, located at the bottom of a steep slope at 70 m

Research paper thumbnail of Late Pleistocene and early Holocene ecological response of Lake El Trébol (Patagonia, Argentina) to environmental changes

Journal of Paleolimnology, 1999

Stratigraphy of Lake El Trébol (41°S 71°W, 758 m a.s.l.) described from an 11 m long sediment cor... more Stratigraphy of Lake El Trébol (41°S 71°W, 758 m a.s.l.) described from an 11 m long sediment core provided a continuous record of patecenvironmental changes occurred during the last 14,000 years in southern South America east of the Andes. Located in an ecotonal area within a strong humidity gradient, this lake offers a unique opportunity to develop paleolimnological studies. Using

Research paper thumbnail of Interactions of temperature and nutrient changes: effects on phytoplankton in the Piburger See (Tyrol, Austria)

Freshwater Biology, 2011

... H. THIES*, M. TOLOTTI†, U. NICKUS‡, A. LAMI§ , S. MUSAZZI§ , P. GUILIZZONI§ , NL ROSE– AND H.... more ... H. THIES*, M. TOLOTTI†, U. NICKUS‡, A. LAMI§ , S. MUSAZZI§ , P. GUILIZZONI§ , NL ROSE– AND H. YANG– *Institute of Ecology, University of Innsbruck, Innsbruck, Austria †IASMA Research and Innovation Centre, E. Mach Foundation, San Michele all'Adige, Italy ‡Institute ...

Research paper thumbnail of Ecology of high altitude aquatic systems in the Alps

Research paper thumbnail of Limnology of high altitude lakes in the Mt Everest Region (Himalayas, Nepal)

... The chemistry of 31 lakes at altitudes between 4530 and 5480 m asl in the Khumbu and ImjaKola... more ... The chemistry of 31 lakes at altitudes between 4530 and 5480 m asl in the Khumbu and ImjaKola valleys is ... Khumbu Valley (Nepalese Himalayas) Marina MANCA, Delio RUGGIU, Pierisa PANZANI, Alessandra ASIOLI 1) , Graziella MURA 2) and Anna Maria NOCENTINI CNR ...

Research paper thumbnail of Paleolimnology and ecosystem dynamics at remote European Alpine lakes: MOuntain LAkes Research programme, MOLAR

Research paper thumbnail of Ricostruzione paleolimnologica degli ultimi 400 anni del Lago di Tovel (Dolomiti di Brenta)

Research paper thumbnail of The sediment core analyses in high altitude lakes of Central Alps: Comparison of three inferring-pH techniques and effect of temperature on lake acidification

Research paper thumbnail of Indagini paleolimnologiche sul lago di Tovel (Trentino)

Research paper thumbnail of Lakes Albano and Nemi (central Italy): an overview

... Ist. ital. Idrobiol., 55: 17-22, 1996 Lakes Albano and Nemi (central Italy): an overview Chri... more ... Ist. ital. Idrobiol., 55: 17-22, 1996 Lakes Albano and Nemi (central Italy): an overview Christina CHONDROGIANNI1, Daniel ARIZTEGUI1, Piero GUILIZZONI2 and Andrea LAMI2 ... 1993), Martignano (Kelly & Huntley 1991), Valle di Castiglione (Follieri et al. ...

Research paper thumbnail of Environmental changes in the Rila Mountains, Southwestern Bulgaria, as recorded by the sediments of a remote lake

Advances in Limnology, 2009

ABSTRACT Abstract: Chemical and biological sedimentary records of the high alpine lake “Bubreka”,... more ABSTRACT Abstract: Chemical and biological sedimentary records of the high alpine lake “Bubreka”, Rila Mountains, Bulgaria, were used to reconstruct palaeoecological conditions and to determine the phases in the ontogeny of the lake. Sediment cores taken in 2000 were dated by 210Pb and 137Cs and analysed for percentage of dry weight (%DW), loss-on-ignition (LOI), pigments, diatoms, chrysophyte stomatocysts, cladocerans, chironomids and spheroidal carbonaceous particles (SCPs). The studies on Lake Bubreka show that high mountain lakes are good sites for the study of the evolution and effects of the long range transport of atmospheric pollutants from the industrial lowlands to mountain regions. Four distinct successional phases can be described in the lake history during the last ~ 250 years, revealing complex interactions between anthropogenic impact and climate. Phase 1 (c. AD 1762-1834) is characterised by stable oligotrophical conditions. During Phase 2 (c. AD 1834 -1928) there is a change from oligotrophic to mesotrophic conditions. Phase 3 (c. AD 1928 - 1994 ± 2) shows an increase in LOI due to the high proportion of organic material. The shorter ice cover period in the lake may have created conditions more suitable for the growth of phyto- and zooplankton and changed the overall primary production from benthos to plankton. In Phase 4 (c. AD 1994 ± 2 - 2000) there is increased LOI, increasing percentages of periphytic diatoms, less favorable conditions for cladocerans, and rheophilic chironomid assemblages which indicate rapid input of nutrients causing mesotrophication. The SCP record and comparisons with other European mountain lakes suggest there is a moderate impact from atmospheric deposition compared with similar lakes elsewhere in Europe.

Research paper thumbnail of Sub-fossil pigments as a guide to the phytoplankton history of the acidified Lake Orta (N. Italy)

SIL Proceedings, 1922-2010, 1988

Research paper thumbnail of A Comparison of Constitutive and Inducible Non-Endogenous Keto-Carotenoids Biosynthesis in Synechocystis sp. PCC 6803

Microorganisms, 2019

The model cyanobacterium Synechocystis sp. PCC 6803 has gained significant attention as an altern... more The model cyanobacterium Synechocystis sp. PCC 6803 has gained significant attention as an alternative and sustainable source for biomass, biofuels and added-value compounds. The latter category includes keto-carotenoids, which are molecules largely employed in a wide spectrum of industrial applications in the food, feed, nutraceutical, cosmetic and pharmaceutical sectors. Keto-carotenoids are not naturally synthesized by Synechocystis, at least in any significant amounts, but their accumulation can be induced by metabolic engineering of the endogenous carotenoid biosynthetic pathway. In this study, the accumulation of the keto-carotenoids astaxanthin and canthaxanthin, resulting from the constitutive or temperature-inducible expression of the CrtW and CrtZ genes from Brevundimonas, is compared. The benefits and drawbacks of the two engineering approaches are discussed.

Research paper thumbnail of Preliminary results on palaeolimnology of the crater Lake Albano (Latium, Italy)

SIL Proceedings, 1922-2010, 1993

Research paper thumbnail of A multi-proxy analysis of climate impacts on the recent development of subarctic Lake Saanajärvi in Finnish Lapland

Journal of Paleolimnology, 2002

Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern... more Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern Finnish Lapland are studied by comparison of various biological and sedimentological proxies with the 200-year long climate record, specifically reconstructed for the site using a data-set of European-wide meteorological data. The multi-proxy evidence of simultaneously changing diatom, Cladocera, and chrysophyte assemblages along with the increased rates

Research paper thumbnail of Evidence for short-lived oscillations in the biological records from the sediments of Lago Albano (Central Italy) spanning the period ca. 28 to 17 k yr BP

Journal of Paleolimnology, 2000

We report the results of analyses of pigments (derived from algae and photosynthetic bacteria), d... more We report the results of analyses of pigments (derived from algae and photosynthetic bacteria), diatoms and invertebrate fossil remains (ostracods, cladocerans, chironomids) in two late Pleistocene sediment cores from Lago Albano, a crater lake in Central Italy. The record contains evidence for oscillations in lake biota throughout the period ca. 28 to 17 k yr BP. The earliest of these

Research paper thumbnail of Lacustrine organic matter and the Holocene paleoenvironmental record of Lake Albano (central Italy)

Journal of Paleolimnology, 2001

A combined bulk and detailed geochemical study of the sedimentary organic matter in Lake Albano, ... more A combined bulk and detailed geochemical study of the sedimentary organic matter in Lake Albano, central Italy, provides critical data to track the response of this aquatic system to the environmental changes of variable amplitude that occurred during the Holocene. Rock-Eval pyrolysis of this predominantly laminated, organic carbon-rich sedimentary sequence shows changes in hydrogen and oxygen indices that are related

Research paper thumbnail of Lake Redó ecosystem response to an increasing warming in the Pyrenees during the twentieth century

Journal of Paleolimnology, 2002

The ecosystem response of Lake Redó (Central Pyrenees) to fluctuations in seasonal air temperatur... more The ecosystem response of Lake Redó (Central Pyrenees) to fluctuations in seasonal air temperature during the last two centuries was investigated by comparison of reconstructed air temperatures with the sediment record. Fine slicing allowed a resolution of 3-6 years according to the 210 Pb dating, although it was still difficult to easily investigate the response to air temperature forcing, since extreme fluctuations in temperature occur on interannual timescales. However, the resolution was sufficient to show responses on decadal and century scales. An overall tendency to warming in mean annual temperature in the Central Pyrenees has been caused by summer and in particular by autumn increases. Many of the measured sediment variables apparently responded to these long term trends, but the significance of the relationships was highly conditioned by the structure of the data. The variables responding most on the finer time scales were the microfossils. For diatoms, chironomids and chrysophytes the main variability correlated to summer and to autumn temperatures. For two planktonic species, Fragilaria nanana and Cyclotella pseudostelligera, we found a link of their variability with temperature fluctuations in their growing months (September and October, respectively). This relationship appeared at a certain point during a general warming trend, indicating a threshold in the response. On the other hand, no significant changes in the dominant species could be linked to temperature, nor in any significant subgroup of the 180 diatom species present in the core. In contrast, for most chironomids (particularly Paratanytarsus austriacus, Heterotrissocladius marcidus and Micropsectra radialis) a negative relationship with summer temperature extended throughout the studied period. This response of the whole group gives chironomids a more robust role as indicators for recording temperature changes on long timescales (e.g., through the Holocene) and for lake signal inter-comparison. Finally, our results indicated that, in all cases, there was a significant resilience to high frequency changes and hysteresis despite extreme fluctuations. Although we were dealing with organisms with one or many generations per year, their populations seemed to follow the decadal trends in air temperature. Mountain Lake Research MOLAR This is the ninth of 11 papers published in this special issue on the palaeolimnology of remote mountain lakes in Europe resulting from the MOLAR project funded by the European Union. The guest editor was Richard W. Battarbee.

Research paper thumbnail of The environmental history of a mountain lake (Lago Paione Superiore, Central Alps, Italy) for the last c. 100 years: a multidisciplinary, palaeolimnological study

Journal of Paleolimnology, 1996

... main objectives of the AL:PE programme (Acidifica-tion of Mountain lakes: Palaeolimnology and... more ... main objectives of the AL:PE programme (Acidifica-tion of Mountain lakes: Palaeolimnology and Ecology, a project supported by the Commission of the European Community; Wathne & Patrick, 1994), of which the present study is one part. ...

Research paper thumbnail of Stratigraphy of specific algal and bacterial carotenoids in the sediments of Lake Varese (N. Italy)

Hydrobiologia, 1986

A study on the succession of some phytoplankton populations in the very eutrophic Lake Varese ove... more A study on the succession of some phytoplankton populations in the very eutrophic Lake Varese over the past 80–100 years, was based on thin-layer chromatography of four group-specific carotenoids (echinenone, lutein, myxoxanthophyll and oscillaxanthin). The development of diatoms was traced by microscope counts of their frustules. In addition, the carotenoid okenone, peculiar to some Chromatium species, was identified and related

Research paper thumbnail of The late Pleistocene ostracod record of the crater lake sediments from Lago di Albano (Central Italy): changes in trophic status, water level and climate

Journal of Paleolimnology, 1999

Four cores (ranging between ca. 9 and ca. 14 m in length) from Lago di Albano in Central Italy we... more Four cores (ranging between ca. 9 and ca. 14 m in length) from Lago di Albano in Central Italy were studied for their ostracod content, as well as algal and bacterial pigments, CaCO3 and concentration of organic matter. Cores PALB 94 1E and PALB 94 1C from Site 1, located at the bottom of a steep slope at 70 m

Research paper thumbnail of Late Pleistocene and early Holocene ecological response of Lake El Trébol (Patagonia, Argentina) to environmental changes

Journal of Paleolimnology, 1999

Stratigraphy of Lake El Trébol (41°S 71°W, 758 m a.s.l.) described from an 11 m long sediment cor... more Stratigraphy of Lake El Trébol (41°S 71°W, 758 m a.s.l.) described from an 11 m long sediment core provided a continuous record of patecenvironmental changes occurred during the last 14,000 years in southern South America east of the Andes. Located in an ecotonal area within a strong humidity gradient, this lake offers a unique opportunity to develop paleolimnological studies. Using

Research paper thumbnail of Interactions of temperature and nutrient changes: effects on phytoplankton in the Piburger See (Tyrol, Austria)

Freshwater Biology, 2011

... H. THIES*, M. TOLOTTI†, U. NICKUS‡, A. LAMI§ , S. MUSAZZI§ , P. GUILIZZONI§ , NL ROSE– AND H.... more ... H. THIES*, M. TOLOTTI†, U. NICKUS‡, A. LAMI§ , S. MUSAZZI§ , P. GUILIZZONI§ , NL ROSE– AND H. YANG– *Institute of Ecology, University of Innsbruck, Innsbruck, Austria †IASMA Research and Innovation Centre, E. Mach Foundation, San Michele all'Adige, Italy ‡Institute ...

Research paper thumbnail of Ecology of high altitude aquatic systems in the Alps

Research paper thumbnail of Limnology of high altitude lakes in the Mt Everest Region (Himalayas, Nepal)

... The chemistry of 31 lakes at altitudes between 4530 and 5480 m asl in the Khumbu and ImjaKola... more ... The chemistry of 31 lakes at altitudes between 4530 and 5480 m asl in the Khumbu and ImjaKola valleys is ... Khumbu Valley (Nepalese Himalayas) Marina MANCA, Delio RUGGIU, Pierisa PANZANI, Alessandra ASIOLI 1) , Graziella MURA 2) and Anna Maria NOCENTINI CNR ...

Research paper thumbnail of Paleolimnology and ecosystem dynamics at remote European Alpine lakes: MOuntain LAkes Research programme, MOLAR

Research paper thumbnail of Ricostruzione paleolimnologica degli ultimi 400 anni del Lago di Tovel (Dolomiti di Brenta)

Research paper thumbnail of The sediment core analyses in high altitude lakes of Central Alps: Comparison of three inferring-pH techniques and effect of temperature on lake acidification

Research paper thumbnail of Indagini paleolimnologiche sul lago di Tovel (Trentino)

Research paper thumbnail of Lakes Albano and Nemi (central Italy): an overview

... Ist. ital. Idrobiol., 55: 17-22, 1996 Lakes Albano and Nemi (central Italy): an overview Chri... more ... Ist. ital. Idrobiol., 55: 17-22, 1996 Lakes Albano and Nemi (central Italy): an overview Christina CHONDROGIANNI1, Daniel ARIZTEGUI1, Piero GUILIZZONI2 and Andrea LAMI2 ... 1993), Martignano (Kelly & Huntley 1991), Valle di Castiglione (Follieri et al. ...