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Tolotti M, Brighenti S, Bruno MC, Cerasino L, Pindo M, Tirler W, Albanese D. Ecological "Windows of opportunity" influence biofilm prokaryotic diversity differently in glacial and non-glacial Alpine streams. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 944:173826. [PMID: 38866149 DOI: 10.1016/j.scitotenv.2024.173826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2024] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 06/14/2024]
Abstract
In glacier-fed streams, the Windows of Opportunity (WOs) are periods of mild environmental conditions supporting the seasonal development of benthic microorganisms. WOs have been defined based on changes in biofilm biomass, but the responses of microbial diversity to WOs in Alpine streams have been overlooked. A two year (2017-2018) metabarcoding of epilithic and epipsammic biofilm prokaryotes was conducted in Alpine streams fed by glaciers (kryal), rock glaciers (rock glacial), or groundwater/precipitation (krenal) in two catchments of the Central-Eastern European Alps (Italy), aiming at testing the hypothesis that: 1) environmental WOs enhance not only the biomass but also the α-diversity of the prokaryotic biofilm in all stream types, 2) diversity and phenology of prokaryotic biofilm are mainly influenced by the physical habitat in glacial streams, and by water chemistry in the other two stream types. The study confirmed kryal and krenal streams as endmembers of epilithic and sediment prokaryotic α- and β-diversity, with rock glacial streams sharing a large proportion of taxa with the two other stream types. Alpha-diversity appeared to respond to ecological WOs, but, contrary to expectations, seasonality was less pronounced in the turbid kryal than in the clear streams. This was attributed to the small size of the glaciers feeding the studied kryal streams, whose discharge dynamics were those typical of the late phase of deglaciation. Prokaryotic α-diversity of non-glacial streams tended to be higher in early summer than in early autumn. Our findings, while confirming that high altitude streams are heavily threatened by climate change, underscore the still neglected role of rock glacier runoffs as climate refugia for the most stenothermic benthic aquatic microorganism. This advocates the need to define and test strategies for protecting these ecosystems for preserving, restoring, and connecting cold Alpine aquatic biodiversity in the context of the progressing global warming.
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Affiliation(s)
- Monica Tolotti
- Research and Innovation Centre, Fondazione Edmund Mach, S. Michele all'Adige, Italy; National Biodiversity Future Center (NBFC), Università di Palermo, Palermo, Italy.
| | - Stefano Brighenti
- Competence Centre for Mountain Innovation Ecosystems, Free University of Bolzano, Bolzano/Bozen, Italy
| | - Maria Cristina Bruno
- Research and Innovation Centre, Fondazione Edmund Mach, S. Michele all'Adige, Italy; National Biodiversity Future Center (NBFC), Università di Palermo, Palermo, Italy
| | - Leonardo Cerasino
- Research and Innovation Centre, Fondazione Edmund Mach, S. Michele all'Adige, Italy
| | - Massimo Pindo
- Research and Innovation Centre, Fondazione Edmund Mach, S. Michele all'Adige, Italy
| | | | - Davide Albanese
- Research and Innovation Centre, Fondazione Edmund Mach, S. Michele all'Adige, Italy
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Wade AJ, Yapiyev V, Shahgedanova M, Saidaliyeva Z, Madibekov A, Kapitsa V, Kasatkin N, Ismukhanova L, Kulbekova R, Sultanbekova B, Severskiy I, Esenaman M, Kalashnikova O, Usubaliev R, Akbarov F, Umirzakov G, Petrov M, Rakhimov I, Kayumova D, Kayumov A. Cryosphere and land cover influence on stream water quality in Central Asia's glacierized catchments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 939:173525. [PMID: 38810747 DOI: 10.1016/j.scitotenv.2024.173525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 05/21/2024] [Accepted: 05/24/2024] [Indexed: 05/31/2024]
Abstract
This work helps address recent calls for systematic water quality assessment in Central Asia and considers how nutrient and salinity sources, and transport, affect water quality along the continuum from the cryosphere to the lowland plains. Spatial and, for the first time, temporal variations in stream water pH, temperature, electrical conductivity, and nitrate and phosphate concentrations are presented for four catchments (485-13,500 km2), all with glaciers and major urban areas. The catchments studied were: Kaskelen (Kazakhstan), Ala-Archa (Kyrgyzstan), Chirchik (Uzbekistan) and the Kofarnihon (Tajikistan). Measurements were made in cryosphere, stream water, groundwater, reservoir and lake samples over a 22-month period at fortnightly intervals from 35 sites. The results highlight that glacier, permafrost and rock glacier outflows were primary and secondary nitrate sources (>1 mg N L-1) to the headwaters, and there were major increases in salinity and nitrate concentrations where rivers receive inputs from agriculture and settlements. Overall, the water quality complied with national and World Health Organization standards, however there were pollution hot-spots with shallow urban groundwaters contaminated with nitrate (>11 mg N L-1) and stream electrical conductivity above 800 μS cm-1 in some agricultural areas indicative of high salinity. Phosphate concentrations were generally low (<0.06 mg P L-1) throughout the catchments, though elevated (>0.2 mg P L-1) in urban areas due to effluent contamination. A melt water dilution effect along the main river channels was discernible, in the electrical conductivity and nitrate concentration seasonal dynamics, 100 s of km from the headwaters. Thus, the input of relatively clean water from the cryosphere is an important regulator of main channel water quality in the urban and farmed lowland plains adjacent to the Tien Shan and Pamir. Improved sewage treatment is needed in urban areas.
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Affiliation(s)
- Andrew J Wade
- Department of Geography and Environmental Science, University of Reading, Reading RG6 6DW, UK.
| | - Vadim Yapiyev
- Department of Geography and Environmental Science, University of Reading, Reading RG6 6DW, UK; School of Mining and Geosciences, Nazarbayev University, Astana, Kazakhstan
| | - Maria Shahgedanova
- Department of Geography and Environmental Science, University of Reading, Reading RG6 6DW, UK
| | - Zarina Saidaliyeva
- Department of Geography and Environmental Science, University of Reading, Reading RG6 6DW, UK
| | | | - Vassiliy Kapitsa
- Institute of Geography and Water Security, Almaty, Kazakhstan; Central Asia Regional Glaciological Centre under the Auspices of UNESCO, Almaty, Kazakhstan
| | - Nikolay Kasatkin
- Institute of Geography and Water Security, Almaty, Kazakhstan; Central Asia Regional Glaciological Centre under the Auspices of UNESCO, Almaty, Kazakhstan
| | | | - Roza Kulbekova
- Institute of Geography and Water Security, Almaty, Kazakhstan
| | | | - Igor Severskiy
- Institute of Geography and Water Security, Almaty, Kazakhstan; Central Asia Regional Glaciological Centre under the Auspices of UNESCO, Almaty, Kazakhstan
| | | | - Olga Kalashnikova
- Central-Asian Institute for Applied Geosciences, Bishkek, Kyrgyzstan
| | - Ryskul Usubaliev
- Central-Asian Institute for Applied Geosciences, Bishkek, Kyrgyzstan
| | - Fakhriddin Akbarov
- Centre of Glacial Geology, Institute of Geology and Geophysics named after. H.M. Abdullaev at the University of Geological Sciences under the Ministry of Geology and Mining of the Republic of Uzbekistan, Tashkent, Uzbekistan
| | - Gulomjon Umirzakov
- National University of Uzbekistan, Tashkent, Uzbekistan; Hydrometeorological Research Institute, Tashkent, Uzbekistan
| | - Maksim Petrov
- Centre of Glacial Geology, Institute of Geology and Geophysics named after. H.M. Abdullaev at the University of Geological Sciences under the Ministry of Geology and Mining of the Republic of Uzbekistan, Tashkent, Uzbekistan
| | | | - Dilorom Kayumova
- State Scientific Institution 'Center for Research of Glaciers of the Academy of Sciences of the Republic of Tajikistan', Dushanbe, Tajikistan
| | - Abdulhamid Kayumov
- State Scientific Institution 'Center for Research of Glaciers of the Academy of Sciences of the Republic of Tajikistan', Dushanbe, Tajikistan
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Mingyue L, Xuejun S, Shengnan L, Jie W, Zijian L, Qianggong Z. Hydrochemistry dynamics in a glacierized headwater catchment of Lhasa River, Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170810. [PMID: 38336076 DOI: 10.1016/j.scitotenv.2024.170810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/26/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Mountain glaciers are essential for supplying water resources that sustain downstream communities and livelihoods, yet the hydrogeochemical dynamics at glacier terminals and the impact of glacier retreat on downstream water chemistry are not fully understood. This study addresses this by conducting comprehensive observations and analysis of water chemistry at refined spatial and temporal resolutions in the Lhasa River Valley Glacier No. 1 (LRVG-1) catchment, a vital source of drinking and irrigation water for the local population on the Tibetan Plateau. Our findings reveal a weakly alkaline water environment within this glacierized basin, with HCO3- and Ca2+ as the dominant anions and cations, respectively, resulting in a hydrochemical pattern classified as HCO3--Ca2+ type. Solute concentrations increase along the glacier meltwater pathway, influenced by water-rock interaction, dilution, and diverse sources. The cations are predominantly from carbonate weathering, constituting 72.86 % of the total cations, followed by sulfide oxidation (11.08 %), glacier meltwater inputs (8.13 %), and silicate weathering (7.93 %). The contribution of cations from glacier meltwater diminishes as they travel along the glacier meltwater flow pathway. Our study indicates the localized yet significant impact of glacier meltwater on hydrochemistry, particularly in the vicinity of the glacier terminus. We recommend considering glacial meltwater and the entire glacier watershed as a continuum, essential for understanding the cumulative effects of glacier melt and human activities on water quality. This perspective is crucial for predicting future river chemistry trajectories in high-mountain basins and informing policy-making for water quality conservation across the Tibetan Plateau.
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Affiliation(s)
- Li Mingyue
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Sun Xuejun
- School of Environmental and Resource Sciences, Shanxi University, Taiyuan 030006, China
| | - Li Shengnan
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wang Jie
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lu Zijian
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhang Qianggong
- State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Lhasa Earth System Multi-Dimension Observatory Network (LEMON), Lhasa 850000, China.
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4
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Bearzot F, Colombo N, Cremonese E, di Cella UM, Drigo E, Caschetto M, Basiricò S, Crosta GB, Frattini P, Freppaz M, Pogliotti P, Salerno F, Brunier A, Rossini M. Hydrological, thermal and chemical influence of an intact rock glacier discharge on mountain stream water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162777. [PMID: 36906009 DOI: 10.1016/j.scitotenv.2023.162777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/06/2023] [Accepted: 03/06/2023] [Indexed: 06/18/2023]
Abstract
Rock glaciers are the most prominent permafrost-related mountain landforms. This study investigates the effects of the discharge from an intact rock glacier on the hydrological, thermal and chemical dynamics of a high-elevation stream in the NW Italian Alps. Despite draining only 39 % of the watershed area, the rock glacier sourced a disproportionately large amount of discharge to the stream, with the highest relative contribution to the catchment streamflow occurring in late summer - early autumn (up to 63 %). However, ice melt was estimated to be only a minor component to the discharge of the rock glacier, due to its insulating coarse debris mantle. The sedimentological characteristics and internal hydrological system of the rock glacier played a major role in its capability to store and transmit relevant amounts of groundwater, especially during the baseflow periods. Besides the hydrological influence, the cold and solute-enriched discharge from the rock glacier significantly lowered the stream water temperature (especially during warm atmospheric periods) as well as increased the concentrations of most solutes in the stream. Furthermore, in the two lobes forming the rock glacier, different internal hydrological systems and flowpaths, likely driven by different permafrost and ice content, caused contrasting hydrological and chemical behaviours. Indeed, higher hydrological contributions and significant seasonal trends in solute concentrations were found in the lobe with higher permafrost and ice content. Our results highlight the relevance of rock glaciers as water resources, despite the minor ice melt contribution, also suggesting their potential, increasing hydrological importance in the light of climate warming.
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Affiliation(s)
- F Bearzot
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy; Faculty of Science and Technology, Free University of Bozen-Bolzano, Bozen, Italy.
| | - N Colombo
- Water Research Institute, National Research Council of Italy, Rome, Italy; Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - E Cremonese
- Environmental Protection Agency of Valle d'Aosta, Climate Change Unit, Saint-Christophe, Italy
| | - U Morra di Cella
- Environmental Protection Agency of Valle d'Aosta, Climate Change Unit, Saint-Christophe, Italy
| | | | - M Caschetto
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy
| | - S Basiricò
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy
| | - G B Crosta
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy
| | - P Frattini
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy
| | - M Freppaz
- Department of Agricultural, Forest and Food Sciences, University of Turin, Grugliasco, Italy
| | - P Pogliotti
- Environmental Protection Agency of Valle d'Aosta, Climate Change Unit, Saint-Christophe, Italy
| | - F Salerno
- Institute of Polar Sciences, National Research Council of Italy, Milan, Italy
| | - A Brunier
- Environmental Protection Agency of Valle d'Aosta, Climate Change Unit, Saint-Christophe, Italy
| | - M Rossini
- Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milan, Italy
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Kaushik H, Soheb M, Biswal K, Ramanathan AL, Kumar O, Patel AK. Understanding the hydrochemical functioning of glacierized catchments of the Upper Indus Basin in Ladakh, Indian Himalayas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:20631-20649. [PMID: 36255575 DOI: 10.1007/s11356-022-23477-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 10/03/2022] [Indexed: 06/16/2023]
Abstract
Recent studies have endorsed that surface water chemical composition in the Himalayas is impacted by climate change-induced accelerated melting of glaciers. Chemical weathering dynamics in the Ladakh region is poorly understood, due to unavailability of in situ dataset. The aim of the present study is to investigate how the two distinct catchments (Lato and Stok) drive the meltwater chemistry of the Indus River and its tributary, in the Western Himalayas. Water samples were collected from two glaciated catchments (Lato and Stok), Chabe Nama (tributary) and the Indus River in Ladakh. The mildly alkaline pH (range 7.3-8.5) and fluctuating ionic trend of the meltwater samples reflected the distinct geology and weathering patterns of the Upper Indus Basin (UIB). Gibbs plot and mixing diagram revealed rock weathering outweighed evaporation and precipitation. The strong associations between Ca2+-HCO3-, Mg2+-HCO3-, Ca2+-Mg2+, Na+-HCO3-, and Mg2+-Na+ demonstrated carbonate rock weathering contributed to the major ion influx. Principal component analysis (PCA) marked carbonate and silicates as the most abundant minerals respectively. Chemical weathering patterns were predominantly controlled by percentage of glacierized area and basin runoff. Thus, Lato with the larger glacierized area (~ 25%) and higher runoff contributed low TDS, HCO3-, Ca2+, and Na+ and exhibited higher chemical weathering, whereas lower chemical weathering was evinced at Stok with the smaller glacierized area (~ 5%). In contrast, the carbonate weathering rate (CWR) of larger glacierized catchments (Lato) exhibits higher average value of 15.7 t/km2/year as compared to smaller glacierized catchment (Stok) with lower average value 6.69 t/km2/year. However, CWR is high in both the catchments compared to silicate weathering rate (SWR). For the first time, in situ datasets for stream water chemical characteristics have been generated for Lato and Stok glaciated catchments in Ladakh, to facilitate healthy ecosystems and livelihoods in the UIB.
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Affiliation(s)
- Himanshu Kaushik
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, 110067, India.
| | - Mohd Soheb
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Kalyan Biswal
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, 110067, India
| | - A L Ramanathan
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Om Kumar
- Department of Environmental Sciences, Lakshmibai College, University of Delhi, Delhi, 110052, India
| | - Arbind Kumar Patel
- School of Environmental Science, Jawaharlal Nehru University, New Delhi, 110067, India
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Zarroca M, Roqué C, Linares R, Salminci JG, Gutiérrez F. Natural acid rock drainage in alpine catchments: A side effect of climate warming. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 778:146070. [PMID: 33711593 DOI: 10.1016/j.scitotenv.2021.146070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/13/2021] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
A historical series of aerial photographs spanning more than 70 years (1945-2018) revealed that natural acid rock drainage (ARD) has experienced an intensification in the Noguera de Vallferrera alpine catchment (Central Pyrenees) due to climate change during the last decade. ARD manifests by the precipitation of whitish aluminum-compounds that strikingly cover the beds of some gullies and streams in high-mountain catchments. The total length of affected streams has increased from ca. 5 km (1945) to more than 35 km (2018). Up to 68 water samples were collected in three main areas to determine the spatial variation in acidity and concentration of dissolved metals, representative of surface and subsurface waters. Concentration of aluminum clearly correlates with acidity of waters. Aluminum precipitation occurs where acidic waters, enriched in metals due ARD related to the oxidation of sulfides, mix with non-acidic waters. In addition to aluminum, other potentially toxic trace metals are present at concentrations well above the quality standards for natural waters. Here, we show that climate warming and the severe droughts recorded in the last decade are the most plausible causes for the observed ARD intensification. This result is supported by a good correlation between the regional ascending rate of the periglacial limits (ca. 46 m-height/decade) and the rising rate of the maximum elevations at which ARD occurs (ca. 45 to 55 m-height/decade). In addition to climatic control, we also show that the local geomorphology is playing a major role. The distribution of periglacial deposits (rock glaciers, protalus ramparts, cones and talus slopes) and deep-seated gravitational slope deformations exert a strong control on the spatial patterns and hydrodynamics of ARD. A better understanding of the phenomenon and the monitoring of its evolution can provide clues on these side effects of climate warming, here and in many other alpine catchments worldwide.
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Affiliation(s)
- Mario Zarroca
- Geology Department, Universitat Autònoma de Barcelona, E-08193-Bellaterra, Barcelona, Spain.
| | - Carles Roqué
- Àrea de Geodinàmica Externa i Geomorfologia, Universitat de Girona, E-17071 Girona, Spain
| | - Rogelio Linares
- Geology Department, Universitat Autònoma de Barcelona, E-08193-Bellaterra, Barcelona, Spain
| | - José G Salminci
- Geology Department, Universitat Autònoma de Barcelona, E-08193-Bellaterra, Barcelona, Spain; Geology and Environment Department, Instituto Nacional de Tecnología Industrial (INTI), Avenida General Paz 5445, Buenos Aires, Argentina
| | - Francisco Gutiérrez
- Earth Sciences Department, Universidad de Zaragoza, C/. Pedro Cerbuna 12, E-50009 Zaragoza, Spain
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Brahney J, Bothwell ML, Capito L, Gray CA, Null SE, Menounos B, Curtis PJ. Glacier recession alters stream water quality characteristics facilitating bloom formation in the benthic diatom Didymosphenia geminata. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 764:142856. [PMID: 33092829 DOI: 10.1016/j.scitotenv.2020.142856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/17/2020] [Accepted: 10/02/2020] [Indexed: 06/11/2023]
Abstract
Glaciers provide cold, turbid runoff to many mountain streams in the late summer and buffer against years with low snowfall. The input of glacial meltwater to streams maintains unique habitats and support a diversity of stream flora and fauna. In western Canada, glaciers are anticipated to retreat by 60-80% by the end of the century, and this retreat will invoke widespread changes in mountain ecosystems. We used a space-for-time substitution along a gradient of glacierization in western Canada to develop insights into changes that may occur in glaciated regions over the coming decades. Here we report on observed changes in physical (temperature, turbidity), and chemical (dissolved and total nutrients) characteristics of mountain streams and the associated shifts in their diatom communities during de-glacierization. Shifts in habitat characteristics across gradients include changes in nutrient concentrations, light penetration, temperatures, and flow, all of which have led to distinct changes in diatom community composition. Importantly, glacial-fed rivers were 3-5 °C cooler than rivers without glacial contributions. Declines in glacial meltwater contribution to streams resulted in shifts in the timing of nutrient fluxes and lower concentrations of total phosphorus (TP), soluble reactive phosphorus (SRP), and higher dissolved inorganic nitrogen (DIN) and light penetration. The above set of conditions were linked to the overgrowth of the benthic diatom Didymosphenia geminata. These changes in stream condition and D. geminata colony development primarily occurred in streams with marginal (2-5%) to no glacier cover. Our data support a hypothesis that climate-induced changes in river hydrochemistry and physical condition lead to a phenological mismatch that favors D. geminata bloom development.
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Affiliation(s)
- J Brahney
- Department of Watershed Sciences, Utah State University, Logan, UT 84322, United States of America.
| | - M L Bothwell
- Department of Fisheries and Oceans, Pacific Biological Station, Nanaimo, BC V9T 6N7, Canada
| | - L Capito
- Department of Watershed Sciences, Utah State University, Logan, UT 84322, United States of America
| | - C A Gray
- Department of Wildland Resources, Utah State University, Logan, UT 84322, United States of America
| | - S E Null
- Department of Watershed Sciences, Utah State University, Logan, UT 84322, United States of America
| | - B Menounos
- Geography Program and Natural Resources and Environmental Studies Institute, University of Northern British Columbia, Prince George, BC V6T 1Z9, Canada
| | - P J Curtis
- Department of Earth, Environmental, and Geographic Sciences, University of British Columbia, Okanagan, BC V1V 1V7, Canada
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Modeling Surface Processes on Debris-Covered Glaciers: A Review with Reference to the High Mountain Asia. WATER 2021. [DOI: 10.3390/w13010101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Surface processes on debris-covered glaciers are governed by a variety of controlling factors including climate, debris load, water bodies, and topography. Currently, we have not achieved a general consensus on the role of supraglacial processes in regulating climate–glacier sensitivity in High Mountain Asia, which is mainly due to a lack of an integrated understanding of glacier surface dynamics as a function of debris properties, mass movement, and ponding. Therefore, further investigations on supraglacial processes is needed in order to provide more accurate assessments of the hydrological cycle, water resources, and natural hazards in the region. Given the scarcity of long-term in situ data and the difficulty of conducting fieldwork on these glaciers, many numerical models have been developed by recent studies. This review summarizes our current knowledge of surface processes on debris-covered glaciers with an emphasis on the related modeling efforts. We present an integrated view on how numerical modeling provide insights into glacier surface ablation, supraglacial debris transport, morphological variation, pond dynamics, and ice-cliff evolution. We also highlight the remote sensing approaches that facilitate modeling, and discuss the limitations of existing models regarding their capabilities to address coupled processes on debris-covered glaciers and suggest research directions.
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9
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Rogora M, Somaschini L, Marchetto A, Mosello R, Tartari GA, Paro L. Decadal trends in water chemistry of Alpine lakes in calcareous catchments driven by climate change. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 708:135180. [PMID: 31812417 DOI: 10.1016/j.scitotenv.2019.135180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/22/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
High mountain lakes are considered sensitive indicators of the effects of natural and anthropogenic drivers, including atmospheric deposition and climate change. In this study, we assess long-term trends in the chemistry of a group of high altitude lakes in the Western Alps, Italy, lying in bedrock with a relevant presence of basic, soluble rocks. An in-depth investigation was performed on two key-sites (Lakes Boden Inferiore and Superiore) for which continuous chemical data are available for a period of 30 years. A group of 10 additional lakes in the same area was also considered; these lakes were sampled at the end of the ice-free period during irregular surveys in the period 1980-2017. Water samples were analysed for the main chemical variables, including pH, electrical conductivity, major ions (Ca2+, Mg2+, Na+, K+, HCO3-, Cl-, SO42-, NO3-) and algal nutrients (phosphorus and nitrogen compounds, reactive silica). A steep increase in conductivity and ion concentrations was detected at the key-sites: conductivity increased from 40-45 to 60-70 µS cm-1 over the period 1984-2017; sulphate concentrations more than doubled over the same period (from 50-60 to 120-180 µeq L-1) and base cations increased from 400-500 to 600-750 µeq L-1. An increase in the solute content was also detected in the survey lakes (average conductivity from 39 ± 20 to 57 ± 23 µS cm-1). The analysis of meteorological data revealed a significant increase of air temperature (0.019 °C y-1 over the period 1950-2017), mainly in spring and summer (0.033 °C y-1), and a decrease of snow cover depth and duration. Meteo-climatic drivers were identified as the responsible for the chemical changes occurred in the lakes. Climate-driven effects on weathering rates were mainly indirect and occurred by affecting the flow paths of water at both surface and subsurface level. Cryosphere modification (reduced snow cover and permafrost thawing) also played a role.
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Affiliation(s)
- M Rogora
- CNR Water Research Institute, L.go Tonolli 50, I-28922 Verbania Pallanza, Italy.
| | - L Somaschini
- CNR Water Research Institute, L.go Tonolli 50, I-28922 Verbania Pallanza, Italy
| | - A Marchetto
- CNR Water Research Institute, L.go Tonolli 50, I-28922 Verbania Pallanza, Italy
| | - R Mosello
- CNR Water Research Institute, L.go Tonolli 50, I-28922 Verbania Pallanza, Italy
| | - G A Tartari
- CNR Water Research Institute, L.go Tonolli 50, I-28922 Verbania Pallanza, Italy
| | - L Paro
- Regional Agency for Environmental Protection of the Piedmont Region (ARPA Piemonte) - Dept. Natural and Environmental Risks - Geological Monitoring and Studies, Via Pio VII, 9, I-10135 Torino, Italy
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10
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Colombo N, Salerno F, Martin M, Malandrino M, Giardino M, Serra E, Godone D, Said-Pullicino D, Fratianni S, Paro L, Tartari G, Freppaz M. Influence of permafrost, rock and ice glaciers on chemistry of high-elevation ponds (NW Italian Alps). THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 685:886-901. [PMID: 31247436 DOI: 10.1016/j.scitotenv.2019.06.233] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 06/14/2019] [Accepted: 06/15/2019] [Indexed: 06/09/2023]
Abstract
Permafrost degradation, rock-glacier thawing, and glacier retreat are influencing surface water quality at high elevations. However, there is a lack of knowledge on the dominant geochemical reactions occurring in different cryospheric conditions and how these reactions change during the ice-free season. In the Col d'Olen area (LTER site, NW Italian Alps), four ponds with similar sizes, located in basins with different cryospheric features (glacier, permafrost, rock glacier, none of these), are present in a geographically limited area. All ponds were sampled weekly in 2015 and partially in 2014. Major ions, selected trace elements, and biotic parameters (dissolved organic carbon-DOC, fluorescence index-FI, and nitrate) are examined to evidence the effect of different cryospheric features on water characteristics. Where cryospheric conditions occur chemical weathering is more intensive, with strong seasonal increase of major ions. Sulphide oxidation dominates in glacier and permafrost lying on acid rocks, probably driven by enhanced weathering of freshly exposed rocks in subglacial environment and recently deglaciated areas, and active layer thickness increase. Differently, carbonation dominates for the rock glacier lying on ultramafic rocks. There, high Ni concentrations originate from dissolution of Mg-bearing rocks in the landform. In all settings, pH neutralisation occurs because of the presence of secondary carbonate lithology and ultramafic rocks. Nitrate highest concentrations and changes occur in cryospheric settings while DOC and FI do not show strong differences and seasonal variations. The establishment of more frequent monitoring for water quality in high-elevated surface waters is necessary to provide greater statistical power to detect changes on longer time scales.
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Affiliation(s)
- N Colombo
- University of Turin, Department of Agricultural, Forest and Food Sciences, Grugliasco, Italy
| | - F Salerno
- CNR-IRSA (National Research Council - Water Research Institute), Brugherio, Italy.
| | - M Martin
- University of Turin, Department of Agricultural, Forest and Food Sciences, Grugliasco, Italy
| | - M Malandrino
- University of Turin, Department of Chemistry, Turin, Italy
| | - M Giardino
- University of Turin, Department of Earth Sciences, Turin, Italy
| | - E Serra
- University of Bern, Institute of Geological Sciences, Bern, Switzerland
| | - D Godone
- CNR-IRPI (National Research Council - Research Institute for Geo-Hydrological Protection), Turin, Italy
| | - D Said-Pullicino
- University of Turin, Department of Agricultural, Forest and Food Sciences, Grugliasco, Italy
| | - S Fratianni
- University of Turin, Department of Earth Sciences, Turin, Italy
| | - L Paro
- Arpa Piemonte, Department of "Natural and Environmental Risks", Turin, Italy
| | - G Tartari
- CNR-IRSA (National Research Council - Water Research Institute), Brugherio, Italy
| | - M Freppaz
- University of Turin, Department of Agricultural, Forest and Food Sciences, Grugliasco, Italy
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11
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Ren Z, Martyniuk N, Oleksy IA, Swain A, Hotaling S. Ecological Stoichiometry of the Mountain Cryosphere. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00360] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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12
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Zhang F, Qaiser FUR, Zeng C, Pant RR, Wang G, Zhang H, Chen D. Meltwater hydrochemistry at four glacial catchments in the headwater of Indus River. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:23645-23660. [PMID: 31203542 DOI: 10.1007/s11356-019-05422-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 05/06/2019] [Accepted: 05/08/2019] [Indexed: 06/09/2023]
Abstract
Glacier runoff shows significant change under global warming in the headwater region of the Indus River with great impact on its highly populated downstream area, but the hydrochemistry characteristics of meltwater and the changing mechanism remain unclear in this region. In this study, runoff water samples were collected during May and June, 2015, from four glacial catchments in the Upper Indus Basin to investigate general characteristics and daytime dynamics of meltwater runoff together with sediment and chemical contents. Results showed that glacier runoff in the studied area had an alkaline pH and much higher sediment yields than the local average of the non-glacier areas. The carbonate-dominated geological feature in the four catchments resulted in single chemical facies of Ca-HCO3. The dominant process determining the glacier runoff chemistry was rock-water interaction, with less soluble minerals and less intensive evaporate weathering in the Passu and Gulmit catchments than the B&B and Hinarchi catchments. Comparing the investigated catchments, the larger glacier with longer flow path exhibited higher runoff but lower melting rate, higher SSC resulting from higher erosive power of flow, and higher solute concentrations as a consequence of more intensive contact of meltwater with rock minerals along the longer flow path. For individual catchments, a negative correlation between TDS and flow rate (R2 = 0.26~0.53) and changing trends of ion ratios with flow rate demonstrated that under intensive melting conditions, rock-water interactions were reduced, resulting in dilution of solutes. Overall, the general chemical characteristics of the investigated glacier runoff indicated geological control, whereas individual glacier illustrated hydrological control on the daytime dynamics of glacier runoff chemistry. The presence of glacier terminal lake and agriculture land can significantly alter the hydrochemistry of downstream runoff.
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Affiliation(s)
- Fan Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | | | - Chen Zeng
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
| | - Ramesh Raj Pant
- Central Department of Environmental Science, Tribhuvan University, Kirtipur, Nepal
| | - Guanxing Wang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hongbo Zhang
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| | - Deliang Chen
- Regional Climate Group, Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
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13
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Parro V, Puente-Sánchez F, Cabrol NA, Gallardo-Carreño I, Moreno-Paz M, Blanco Y, García-Villadangos M, Tambley C, Tilot VC, Thompson C, Smith E, Sobrón P, Demergasso CS, Echeverría-Vega A, Fernández-Martínez MÁ, Whyte LG, Fairén AG. Microbiology and Nitrogen Cycle in the Benthic Sediments of a Glacial Oligotrophic Deep Andean Lake as Analog of Ancient Martian Lake-Beds. Front Microbiol 2019; 10:929. [PMID: 31130930 PMCID: PMC6509559 DOI: 10.3389/fmicb.2019.00929] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 04/12/2019] [Indexed: 02/06/2023] Open
Abstract
Potential benthic habitats of early Mars lakes, probably oligotrophic, could range from hydrothermal to cold sediments. Dynamic processes in the water column (such as turbidity or UV penetration) as well as in the benthic bed (temperature gradients, turbation, or sedimentation rate) contribute to supply nutrients to a potential microbial ecosystem. High altitude, oligotrophic, and deep Andean lakes with active deglaciation processes and recent or past volcanic activity are natural models to assess the feasibility of life in other planetary lake/ocean environments and to develop technology for their exploration. We sampled the benthic sediments (down to 269 m depth) of the oligotrophic lake Laguna Negra (Central Andes, Chile) to investigate its ecosystem through geochemical, biomarker profiling, and molecular ecology studies. The chemistry of the benthic water was similar to the rest of the water column, except for variable amounts of ammonium (up to 2.8 ppm) and nitrate (up to 0.13 ppm). A life detector chip with a 300-antibody microarray revealed the presence of biomass in the form of exopolysaccharides and other microbial markers associated to several phylogenetic groups and potential microaerobic and anaerobic metabolisms such as nitrate reduction. DNA analyses showed that 27% of the Archaea sequences corresponded to a group of ammonia-oxidizing archaea (AOA) similar (97%) to Nitrosopumilus spp. and Nitrosoarchaeum spp. (Thaumarchaeota), and 4% of Bacteria sequences to nitrite-oxidizing bacteria from the Nitrospira genus, suggesting a coupling between ammonia and nitrite oxidation. Mesocosm experiments with the specific AOA inhibitor 2-Phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (PTIO) demonstrated an AOA-associated ammonia oxidation activity with the simultaneous accumulation of nitrate and sulfate. The results showed a rich benthic microbial community dominated by microaerobic and anaerobic metabolisms thriving under aphotic, low temperature (4°C), and relatively high pressure, that might be a suitable terrestrial analog of other planetary settings.
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Affiliation(s)
- Victor Parro
- Centro de Astrobiología (CSIC-INTA), Madrid, Spain
| | | | - Nathalie A. Cabrol
- SETI Institute, Carl Sagan Center, Mountain View, CA, United States
- NASA Ames Research Center, Mountain View, CA, United States
| | | | | | | | | | | | - Virginie C. Tilot
- Instituto Español de Oceanografía (IEO), Málaga, Spain
- Muséum National d’Histoire Naturelle, Paris, France
| | - Cody Thompson
- School of Environmental Sciences, University of Guelph, Guelph, ON, Canada
| | - Eric Smith
- SETI Institute, Carl Sagan Center, Mountain View, CA, United States
| | - Pablo Sobrón
- SETI Institute, Carl Sagan Center, Mountain View, CA, United States
| | | | - Alex Echeverría-Vega
- Centro de Biotecnología, Universidad Católica del Norte, Antofagasta, Chile
- Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Talca, Chile
| | | | - Lyle G. Whyte
- Department of Natural Resource Sciences, McGill University, Montreal, QC, Canada
| | - Alberto G. Fairén
- Centro de Astrobiología (CSIC-INTA), Madrid, Spain
- Department of Astronomy, Cornell University, Ithaca, NY, United States
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14
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Monitoring NDVI Inter-Annual Behavior in Mountain Areas of Mainland Spain (2001–2016). SUSTAINABILITY 2018. [DOI: 10.3390/su10124363] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Currently, there exists growing evidence that warming is amplified with elevation resulting in rapid changes in temperature, humidity and water in mountainous areas. The latter might result in considerable damage to forest and agricultural land cover, affecting all the ecosystem services and the socio-economic development that these mountain areas provide. The Mediterranean mountains, moreover, which host a high diversity of natural species, are more vulnerable to global change than other European ecosystems. The protected areas of the mountain ranges of peninsular Spain could help preserve natural resources and landscapes, as well as promote scientific research and the sustainable development of local populations. The temporal statistical trends (2001–2016) of the MODIS13Q1 Normalized Difference Vegetation Index (NDVI) interannual dynamics are analyzed to explore whether the NDVI trends are found uniformly within the mountain ranges of mainland Spain (altitude > 1000 m), as well as in the protected or non-protected mountain areas. Second, to determine if there exists a statistical association between finding an NDVI trend and the specific mountain ranges, protected or unprotected areas are studied. Third, a possible association between cover types in pure pixels using CORINE (Co-ordination of Information on the Environment) land cover cartography is studied and land cover changes between 2000 and 2006 and between 2006 and 2012 are calculated for each mountainous area. Higher areas are observed to have more positive NDVI trends than negative in mountain areas located in mainland Spain during the 2001–2016 period. The growing of vegetation, therefore, was greater than its decrease in the study area. Moreover, differences in the size of the area between growth and depletion of vegetation patterns along the different mountains are found. Notably, more negatives than expected are found, and fewer positives are found than anticipated in the mountains, such as the Cordillera Cantábrica (C.Cant.) or Montes de Murcia y Alicante (M.M.A). Quite the reverse happened in Pirineos (Pir.) and Montes de Cádiz y Málaga (M.C.M.), among others. The statistical association between the trends found and the land cover types is also observed. The differences observed can be explained since the mountain ranges in this study are defined by climate, land cover, human usage and, to a small degree, by land cover changes, but further detailed research is needed to get in-depth detailed conclusions. Conversely, it is found that, in protected mountain areas, a lower NDVI pixels trend than expected (>20%) occurs, whereas it is less than anticipated in unprotected mountain areas. This could be caused by management and the land cover type.
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15
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Colombo N, Gruber S, Martin M, Malandrino M, Magnani A, Godone D, Freppaz M, Fratianni S, Salerno F. Rainfall as primary driver of discharge and solute export from rock glaciers: The Col d'Olen Rock Glacier in the NW Italian Alps. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 639:316-330. [PMID: 29791884 DOI: 10.1016/j.scitotenv.2018.05.098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 06/08/2023]
Abstract
Three hypotheses exist to explain how meteorological variables drive the amount and concentration of solute-enriched water from rock glaciers: (1) Warm periods cause increased subsurface ice melt, which releases solutes; (2) rain periods and the melt of long-lasting snow enhance dilution of rock-glacier outflows; and (3) percolation of rain through rock glaciers facilitates the export of solutes, causing an opposite effect as that described in hypothesis (2). This lack of detailed understanding likely exists because suitable studies of meteorological variables, hydrologic processes and chemical characteristics of water bodies downstream from rock glaciers are unavailable. In this study, a rock-glacier pond in the North-Western Italian Alps was studied on a weekly basis for the ice-free seasons 2014 and 2015 by observing the meteorological variables (air temperature, snowmelt, rainfall) assumed to drive the export of solute-enriched waters from the rock glacier and the hydrochemical response of the pond (water temperature as a proxy of rock-glacier discharge, stable water isotopes, major ions and selected trace elements). An intra-seasonal pattern of increasing solute export associated with higher rock-glacier discharge was found. Specifically, rainfall, after the winter snowpack depletion and prolonged periods of atmospheric temperature above 0 °C, was found to be the primary driver of solute export from the rock glacier during the ice-free season. This occurs likely through the flushing of isotopically- and geochemically-enriched icemelt, causing concomitant increases in the rock-glacier discharge and the solute export (SO42-, Mg2+, Ca2+, Ni, Mn, Co). Moreover, flushing of microbially-active sediments can cause increases in NO3- export.
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Affiliation(s)
- Nicola Colombo
- University of Turin, Department of Earth Sciences, Via Valperga Caluso, 35, 10125 Turin, Italy; Carleton University, Department of Geography and Environmental Studies, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
| | - Stephan Gruber
- Carleton University, Department of Geography and Environmental Studies, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - Maria Martin
- University of Turin, Department of Agricultural, Forest and Food Sciences, Largo Paolo Braccini, 2, 10095 Grugliasco, Italy
| | - Mery Malandrino
- University of Turin, Department of Chemistry, Via Pietro Giuria, 5, 10125 Turin, Italy
| | - Andrea Magnani
- University of Turin, Department of Agricultural, Forest and Food Sciences, Largo Paolo Braccini, 2, 10095 Grugliasco, Italy
| | - Danilo Godone
- CNR-IRPI (National Research Council - Research Institute for Geo-Hydrological Protection), Strada delle Cacce, 73, 10135 Turin, Italy
| | - Michele Freppaz
- University of Turin, Department of Agricultural, Forest and Food Sciences, Largo Paolo Braccini, 2, 10095 Grugliasco, Italy
| | - Simona Fratianni
- University of Turin, Department of Earth Sciences, Via Valperga Caluso, 35, 10125 Turin, Italy
| | - Franco Salerno
- CNR-IRSA (National Research Council - Water Research Institute), Via del Mulino, 19, 20047 Brugherio, Italy
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16
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Glacier Change, Supraglacial Debris Expansion and Glacial Lake Evolution in the Gyirong River Basin, Central Himalayas, between 1988 and 2015. REMOTE SENSING 2018. [DOI: 10.3390/rs10070986] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Atmospheric sulfur isotopic anomalies recorded at Mt. Everest across the Anthropocene. Proc Natl Acad Sci U S A 2018; 115:6964-6969. [PMID: 29915076 DOI: 10.1073/pnas.1801935115] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Increased anthropogenic-induced aerosol concentrations over the Himalayas and Tibetan Plateau have affected regional climate, accelerated snow/glacier melting, and influenced water supply and quality in Asia. Although sulfate is a predominant chemical component in aerosols and the hydrosphere, the contributions from different sources remain contentious. Here, we report multiple sulfur isotope composition of sedimentary sulfates from a remote freshwater alpine lake near Mount Everest to reconstruct a two-century record of the atmospheric sulfur cycle. The sulfur isotopic anomaly is utilized as a probe for sulfur source apportionment and chemical transformation history. The nineteenth-century record displays a distinct sulfur isotopic signature compared with the twentieth-century record when sulfate concentrations increased. Along with other elemental measurements, the isotopic proxy suggests that the increased trend of sulfate is mainly attributed to enhancements of dust-associated sulfate aerosols and climate-induced weathering/erosion, which overprinted sulfur isotopic anomalies originating from other sources (e.g., sulfates produced in the stratosphere by photolytic oxidation processes and/or emitted from combustion) as observed in most modern tropospheric aerosols. The changes in sulfur cycling reported in this study have implications for better quantification of radiative forcing and snow/glacier melting at this climatically sensitive region and potentially other temperate glacial hydrological systems. Additionally, the unique Δ33S-δ34S pattern in the nineteenth century, a period with extensive global biomass burning, is similar to the Paleoarchean (3.6-3.2 Ga) barite record, potentially providing a deeper insight into sulfur photochemical/thermal reactions and possible volcanic influences on the Earth's earliest sulfur cycle.
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18
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Rogora M, Frate L, Carranza ML, Freppaz M, Stanisci A, Bertani I, Bottarin R, Brambilla A, Canullo R, Carbognani M, Cerrato C, Chelli S, Cremonese E, Cutini M, Di Musciano M, Erschbamer B, Godone D, Iocchi M, Isabellon M, Magnani A, Mazzola L, Morra di Cella U, Pauli H, Petey M, Petriccione B, Porro F, Psenner R, Rossetti G, Scotti A, Sommaruga R, Tappeiner U, Theurillat JP, Tomaselli M, Viglietti D, Viterbi R, Vittoz P, Winkler M, Matteucci G. Assessment of climate change effects on mountain ecosystems through a cross-site analysis in the Alps and Apennines. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 624:1429-1442. [PMID: 29929254 DOI: 10.1016/j.scitotenv.2017.12.155] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 12/11/2017] [Accepted: 12/14/2017] [Indexed: 06/08/2023]
Abstract
Mountain ecosystems are sensitive and reliable indicators of climate change. Long-term studies may be extremely useful in assessing the responses of high-elevation ecosystems to climate change and other anthropogenic drivers from a broad ecological perspective. Mountain research sites within the LTER (Long-Term Ecological Research) network are representative of various types of ecosystems and span a wide bioclimatic and elevational range. Here, we present a synthesis and a review of the main results from ecological studies in mountain ecosystems at 20 LTER sites in Italy, Switzerland and Austria covering in most cases more than two decades of observations. We analyzed a set of key climate parameters, such as temperature and snow cover duration, in relation to vascular plant species composition, plant traits, abundance patterns, pedoclimate, nutrient dynamics in soils and water, phenology and composition of freshwater biota. The overall results highlight the rapid response of mountain ecosystems to climate change, with site-specific characteristics and rates. As temperatures increased, vegetation cover in alpine and subalpine summits increased as well. Years with limited snow cover duration caused an increase in soil temperature and microbial biomass during the growing season. Effects on freshwater ecosystems were also observed, in terms of increases in solutes, decreases in nitrates and changes in plankton phenology and benthos communities. This work highlights the importance of comparing and integrating long-term ecological data collected in different ecosystems for a more comprehensive overview of the ecological effects of climate change. Nevertheless, there is a need for (i) adopting co-located monitoring site networks to improve our ability to obtain sound results from cross-site analysis, (ii) carrying out further studies, in particular short-term analyses with fine spatial and temporal resolutions to improve our understanding of responses to extreme events, and (iii) increasing comparability and standardizing protocols across networks to distinguish local patterns from global patterns.
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Affiliation(s)
- M Rogora
- CNR Institute of Ecosystem Study, Verbania Pallanza, Italy.
| | - L Frate
- DIBT, Envix-Lab, University of Molise, Pesche (IS), Italy
| | - M L Carranza
- DIBT, Envix-Lab, University of Molise, Pesche (IS), Italy
| | - M Freppaz
- DISAFA, NatRisk, University of Turin, Grugliasco (TO), Italy
| | - A Stanisci
- DIBT, Envix-Lab, University of Molise, Pesche (IS), Italy
| | - I Bertani
- Graham Sustainability Institute, University of Michigan, 625 E. Liberty St., Ann Arbor, MI 48104, USA
| | - R Bottarin
- Eurac Research, Institute for Alpine Environment, Bolzano (BZ), Italy
| | - A Brambilla
- Alpine Wildlife Research Centre, Gran Paradiso National Park, Degioz (AO) 11, Valsavarenche, Italy; Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - R Canullo
- School of Biosciences and Veterinary Medicine, Plant Diversity and Ecosystems Management Unit, University of Camerino (MC), Italy
| | - M Carbognani
- Department of Chemistry, Life Sciences and Environmental Sustainability University of Parma, Parma, Italy
| | - C Cerrato
- Alpine Wildlife Research Centre, Gran Paradiso National Park, Degioz (AO) 11, Valsavarenche, Italy
| | - S Chelli
- School of Biosciences and Veterinary Medicine, Plant Diversity and Ecosystems Management Unit, University of Camerino (MC), Italy
| | - E Cremonese
- Environmental Protection Agency of Aosta Valley, ARPA VdA, Climate Change Unit, Aosta, Italy
| | - M Cutini
- Department of Science, University of Roma Tre, Viale G. Marconi, 446-00146 Rome, Italy
| | - M Di Musciano
- Department of Life Health & Environmental Sciences, University of L'Aquila Via Vetoio, 67100 L'Aquila, Italy
| | - B Erschbamer
- University of Innsbruck, Institute of Botany, Sternwartestr 15, A-6020 Insbruck, Austria
| | - D Godone
- CNR IRPI Geohazard Monitoring Group, Strada delle Cacce, 73, 10135 Torino, Italy
| | - M Iocchi
- Department of Science, University of Roma Tre, Viale G. Marconi, 446-00146 Rome, Italy
| | - M Isabellon
- DISAFA, University of Turin, Grugliasco (TO), Italy; Environmental Protection Agency of Aosta Valley, ARPA VdA, Climate Change Unit, Aosta, Italy
| | - A Magnani
- DISAFA, University of Turin, Grugliasco (TO), Italy
| | - L Mazzola
- Sciences and Technologies for Environment and Resources, University of Parma, Italy
| | - U Morra di Cella
- Environmental Protection Agency of Aosta Valley, ARPA VdA, Climate Change Unit, Aosta, Italy
| | - H Pauli
- GLORIA Coordination, Institute for Interdisciplinary Mountain Research, Austrian Academy of Sciences & Center for Global Change and Sustainability, University of Natural Resources and Life Sciences Vienna (BOKU), Silbergasse 30/3, 1190 Vienna, Austria
| | - M Petey
- Environmental Protection Agency of Aosta Valley, ARPA VdA, Climate Change Unit, Aosta, Italy
| | - B Petriccione
- Carabinieri, Biodiversity and Park Protection Dpt., Roma, Italy
| | - F Porro
- Department of Earth and Environmental Sciences, University of Pavia, via Ferrata 1, 27100 Pavia, Italy
| | - R Psenner
- Eurac Research, Institute for Alpine Environment, Bolzano (BZ), Italy; Lake and Glacier Research Group, Institute of Ecology, University of Innsbruck, Technikerstr, 25, 6020 Innsbruck, Austria
| | - G Rossetti
- Department of Environmental Sciences, University of Parma, Parco Area delle Scienze, 33/A, 43100 Parma, Italy
| | - A Scotti
- Eurac Research, Institute for Alpine Environment, Bolzano (BZ), Italy
| | - R Sommaruga
- Lake and Glacier Research Group, Institute of Ecology, University of Innsbruck, Technikerstr, 25, 6020 Innsbruck, Austria
| | - U Tappeiner
- Eurac Research, Institute for Alpine Environment, Bolzano (BZ), Italy
| | - J-P Theurillat
- Centre Alpien de Phytogéographie, Fondation J.-M. Aubert, 1938 Champex-Lac, Switzerland, & Section of Biology, University of Geneva, 1292 Chambésy, Switzerland
| | - M Tomaselli
- Department of Chemistry, Life Sciences and Environmental Sustainability University of Parma, Parma, Italy
| | - D Viglietti
- DISAFA, NatRisk, University of Turin, Grugliasco (TO), Italy
| | - R Viterbi
- Alpine Wildlife Research Centre, Gran Paradiso National Park, Degioz (AO) 11, Valsavarenche, Italy
| | - P Vittoz
- Institute of Earth Surface Dynamics, University of Lausanne, Geopolis, 1015 Lausanne, Switzerland
| | - M Winkler
- GLORIA Coordination, Institute for Interdisciplinary Mountain Research, Austrian Academy of Sciences & Center for Global Change and Sustainability, University of Natural Resources and Life Sciences Vienna (BOKU), Silbergasse 30/3, 1190 Vienna, Austria
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19
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Ilyashuk BP, Ilyashuk EA, Psenner R, Tessadri R, Koinig KA. Rock glaciers in crystalline catchments: Hidden permafrost-related threats to alpine headwater lakes. GLOBAL CHANGE BIOLOGY 2018; 24:1548-1562. [PMID: 29143490 PMCID: PMC5873409 DOI: 10.1111/gcb.13985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 10/24/2017] [Accepted: 11/06/2017] [Indexed: 05/14/2023]
Abstract
A global warming-induced transition from glacial to periglacial processes has been identified in mountainous regions around the world. Degrading permafrost in pristine periglacial environments can produce acid rock drainage (ARD) and cause severe ecological damage in areas underlain by sulfide-bearing bedrock. Limnological and paleolimnological approaches were used to assess and compare ARDs generated by rock glaciers, a typical landform of the mountain permafrost domain, and their effects on alpine headwater lakes with similar morphometric features and underlying bedrock geology, but characterized by different intensities of frost action in their catchments during the year. We argue that ARD and its effects on lakes are more severe in the alpine periglacial belt with mean annual air temperatures (MAAT) between -2°C and +3°C, where groundwater persists in the liquid phase for most of the year, in contrast to ARD in the periglacial belt where frost action dominates (MAAT < -2°C). The findings clearly suggest that the ambient air temperature is an important factor affecting the ARD production in alpine periglacial environments. Applying the paleoecological analysis of morphological abnormalities in chironomids through the past millennium, we tested and rejected the hypothesis that unfavorable conditions for aquatic life in the ARD-stressed lakes are largely related to the temperature increase over recent decades, responsible for the enhanced release of ARD contaminants. Our results indicate that the ARDs generated in the catchments are of a long-lasting nature and the frequency of chironomid morphological deformities was significantly higher during the Little Ice Age (LIA) than during pre- or post-LIA periods, suggesting that lower water temperatures may increase the adverse impacts of ARD on aquatic invertebrates. This highlights that temperature-mediated modulations of the metabolism and life cycle of aquatic organisms should be considered when reconstructing long-term trends in the ecotoxicological state of lakes.
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Affiliation(s)
- Boris P. Ilyashuk
- Institute of EcologyUniversity of InnsbruckInnsbruckAustria
- Institute for Alpine EnvironmentEurac ResearchBozen/BolzanoItaly
| | | | - Roland Psenner
- Institute of EcologyUniversity of InnsbruckInnsbruckAustria
- Institute for Alpine EnvironmentEurac ResearchBozen/BolzanoItaly
| | - Richard Tessadri
- Institute of Mineralogy and PetrographyUniversity of InnsbruckInnsbruckAustria
| | - Karin A. Koinig
- Institute of EcologyUniversity of InnsbruckInnsbruckAustria
- Institute for Alpine EnvironmentEurac ResearchBozen/BolzanoItaly
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