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Styburski J, Skubała K. Do urban air pollutants induce changes in the thallus anatomy and affect the photosynthetic efficiency of the nitrophilous lichen Physcia adscendens? ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:112336-112346. [PMID: 37831253 PMCID: PMC10643396 DOI: 10.1007/s11356-023-30194-4] [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: 03/07/2023] [Accepted: 09/26/2023] [Indexed: 10/14/2023]
Abstract
Lichens are symbiotic organisms that are generally sensitive to air pollution due to their specific biological and physiological features. Physcia adscendens is a nitrophilous lichen well-known for being resistant to air pollution associated with progressive anthropopressure. The aim of this study was to investigate the effect of nitrogen oxides and suspended particulate matter (PM10 and PM2.5) on anatomical structure of the thallus and photobiont's photosynthetic efficiency in P. adscendens inhabiting sites that differ in terms of air pollution level and thereby to determine the relevance of these pollutants for shaping the structure of the thallus and the physiological condition of the photosynthetic partner. We found that P. adscendens from polluted sites had increased thickness of the algal layer and the larger size of the algae cells, but a much lower ratio of the algal layer to the whole thallus. Lichens from highly polluted sites had also higher photosynthetic efficiency, which indicates a relatively good physiological condition of the photobiont. This indicates that the photobiont of P. adscendens is well-adapted to function under air pollution stress which may contribute to its success in colonizing polluted sites. Both changes in the anatomy of the lichen thallus and the efficiency of photosynthesis may be related to the enrichment of the environment with nitrogen. The increased photosynthetic efficiency as well as investment in the size of photobiont cells and growth mycobiont hyphae confirms that P. adscendens is well-adapted to urban conditions; however, the mechanism behind those adaptations needs more focus in the context of global environmental changes.
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Affiliation(s)
- Jakub Styburski
- Institute of Botany, Faculty of Biology, Jagiellonian University, Gronostajowa 3, 30-387, Kraków, Poland.
| | - Kaja Skubała
- Institute of Botany, Faculty of Biology, Jagiellonian University, Gronostajowa 3, 30-387, Kraków, Poland
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2
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Niepsch D, Clarke LJ, Newton J, Tzoulas K, Cavan G. High spatial resolution assessment of air quality in urban centres using lichen carbon, nitrogen and sulfur contents and stable-isotope-ratio signatures. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:58731-58754. [PMID: 36991207 PMCID: PMC10163116 DOI: 10.1007/s11356-023-26652-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 03/22/2023] [Indexed: 05/08/2023]
Abstract
Air pollution and poor air quality is impacting human health globally and is a major cause of respiratory and cardiovascular disease and damage to human organ systems. Automated air quality monitoring stations continuously record airborne pollutant concentrations, but are restricted in number, costly to maintain and cannot document all spatial variability of airborne pollutants. Biomonitors, such as lichens, are commonly used as an inexpensive alternative to assess the degree of pollution and monitor air quality. However, only a few studies combined lichen carbon, nitrogen and sulfur contents, with their stable-isotope-ratio signatures (δ13C, δ15N and δ34S values) to assess spatial variability of air quality and to 'fingerprint' potential pollution sources. In this study, a high-spatial resolution lichen biomonitoring approach (using Xanthoria parietina and Physcia spp.) was applied to the City of Manchester (UK), the centre of the urban conurbation Greater Manchester, including considerations of its urban characteristics (e.g., building heights and traffic statistics), to investigate finer spatial detail urban air quality. Lichen wt% N and δ15N signatures, combined with lichen nitrate (NO3-) and ammonium (NH4+) concentrations, suggest a complex mixture of airborne NOx and NHx compounds across Manchester. In contrast, lichen S wt%, combined with δ34S strongly suggest anthropogenic sulfur sources, whereas C wt% and δ13C signatures were not considered reliable indicators of atmospheric carbon emissions. Manchester's urban attributes were found to influence lichen pollutant loadings, suggesting deteriorated air quality in proximity to highly trafficked roads and densely built-up areas. Lichen elemental contents and stable-isotope-ratio signatures can be used to identify areas of poor air quality, particularly at locations not covered by automated air quality measurement stations. Therefore, lichen biomonitoring approaches provide a beneficial method to supplement automated monitoring stations and also to assess finer spatial variability of urban air quality.
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Affiliation(s)
- Daniel Niepsch
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK.
| | - Leon J Clarke
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK
| | - Jason Newton
- Stable Isotope Ecology Laboratory, Scottish Universities Environmental Research Centre (SUERC), East Kilbride, G75 0QF, UK
| | - Konstantinos Tzoulas
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK
| | - Gina Cavan
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK
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3
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Morillas L, Roales J, Cruz C, Munzi S. Non-Toxic Increases in Nitrogen Availability Can Improve the Ability of the Soil Lichen Cladonia rangiferina to Cope with Environmental Changes. J Fungi (Basel) 2022; 8:jof8040333. [PMID: 35448564 PMCID: PMC9025437 DOI: 10.3390/jof8040333] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 11/30/2022] Open
Abstract
Climate change and atmospheric nitrogen (N) deposition on drylands are greatly threatening these especially vulnerable areas. Soil biocrust-forming lichens in drylands can provide early indicators of these disturbances and play a pivotal role, as they contribute to key ecosystem services. In this study, we explored the effects of different long-term water availability regimes simulating climate changes and their interaction with N addition on the physiological response of the soil lichen Cladonia rangiferina. Three sets of this lichen were subjected to control, reduced watering, and reduced watering and N addition (40 kg NH4NO3 ha−1 year−1) treatments for 16 months. Finally, all samples were subjected to daily hydration cycles with N-enriched water at two levels (40 and 80 kg NH4NO3 ha−1 year−1) for 23 days. We found that reduced watering significantly decreased the vitality of this lichen, whereas N addition unexpectedly helped lichens subjected to reduced watering to cope with stress produced by high temperatures. We also found that long-term exposure to N addition contributed to the acclimation to higher N availability. Overall, our data suggest that the interactions between reduced watering and increased N supply and temperature have an important potential to reduce the physiological performance of this soil lichen.
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Affiliation(s)
- Lourdes Morillas
- Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, 1749-016 Lisbon, Portugal; (J.R.); (C.C.); (S.M.)
- Correspondence:
| | - Javier Roales
- Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, 1749-016 Lisbon, Portugal; (J.R.); (C.C.); (S.M.)
- Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide, Ctra. Utrera Km 1, 41013 Seville, Spain
| | - Cristina Cruz
- Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, 1749-016 Lisbon, Portugal; (J.R.); (C.C.); (S.M.)
| | - Silvana Munzi
- Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, 1749-016 Lisbon, Portugal; (J.R.); (C.C.); (S.M.)
- Centro Interuniversitário de História das Ciências e da Tecnologia Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisbon, Portugal
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4
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Niepsch D, Clarke LJ, Tzoulas K, Cavan G. Distinguishing atmospheric nitrogen compounds (nitrate and ammonium) in lichen biomonitoring studies. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:2021-2036. [PMID: 34870671 DOI: 10.1039/d1em00274k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nitrogen speciation, i.e. distinguishing nitrate (NO3-) and ammonium (NH4+), is commonly undertaken in soil studies, but has not been conducted extensively for lichens. Lichen total nitrogen contents (N wt%) reflect airborne atmospheric nitrogen loadings, originating from anthropogenic sources (e.g. vehicular and agricultural/livestock emissions). Albeit nitrogen being an essential lichen nutrient, nitrogen compound (i.e. NO3- and NH4+) concentrations in the atmosphere can have deleterious effects on lichens. Moreover, N wt% do not provide information on individual nitrogen compounds, i.e. NO3- and NH4+ which are major constituents of atmospheric particulate matter (e.g. PM10 and PM2.5). This study presents a novel method to separate and quantify NO3- and NH4+ extracted from lichen material. An optimal approach was identified by testing different strengths and volumes of potassium chloride (KCl) solutions and variable extraction times, i.e. the use of 3% KCl for 6 hours can achieve a same-day extraction and subsequent ion chromatography (IC) analysis for reproducible lichen nitrate and ammonium concentration determinations. Application of the method was undertaken by comparing urban and rural Xanthoria parietina samples to investigate the relative importance of the two nitrogen compounds in contrasting environments. Findings presented showed that lichen nitrogen compound concentrations varied in rural and urban X. parietina samples, suggesting different atmospheric nitrogen loadings from potentially different sources (e.g. agricultural and traffic) and varied deposition patterns (e.g. urban layout impacts). Despite potential impacts of nitrogen compounds on lichen metabolism, the approach presented here can be used for quantification of two different nitrogen compounds in lichen biomonitoring studies that will provide specific information on spatial and temporal variability of airborne NO3- and NH4+ concentrations that act as precursors of particulate matter, affecting air quality and subsequently human health.
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Affiliation(s)
- Daniel Niepsch
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK.
| | - Leon J Clarke
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK.
| | - Konstantinos Tzoulas
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK.
| | - Gina Cavan
- Department of Natural Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, M1 5GD, UK.
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5
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Gasulla F, del Campo EM, Casano LM, Guéra A. Advances in Understanding of Desiccation Tolerance of Lichens and Lichen-Forming Algae. PLANTS (BASEL, SWITZERLAND) 2021; 10:807. [PMID: 33923980 PMCID: PMC8073698 DOI: 10.3390/plants10040807] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/14/2021] [Accepted: 04/16/2021] [Indexed: 12/11/2022]
Abstract
Lichens are symbiotic associations (holobionts) established between fungi (mycobionts) and certain groups of cyanobacteria or unicellular green algae (photobionts). This symbiotic association has been essential in the colonization of terrestrial dry habitats. Lichens possess key mechanisms involved in desiccation tolerance (DT) that are constitutively present such as high amounts of polyols, LEA proteins, HSPs, a powerful antioxidant system, thylakoidal oligogalactolipids, etc. This strategy allows them to be always ready to survive drastic changes in their water content. However, several studies indicate that at least some protective mechanisms require a minimal time to be induced, such as the induction of the antioxidant system, the activation of non-photochemical quenching including the de-epoxidation of violaxanthin to zeaxanthin, lipid membrane remodeling, changes in the proportions of polyols, ultrastructural changes, marked polysaccharide remodeling of the cell wall, etc. Although DT in lichens is achieved mainly through constitutive mechanisms, the induction of protection mechanisms might allow them to face desiccation stress in a better condition. The proportion and relevance of constitutive and inducible DT mechanisms seem to be related to the ecology at which lichens are adapted to.
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Affiliation(s)
- Francisco Gasulla
- Department of Life Sciences, Universidad de Alcalá, Alcalá de Henares, 28802 Madrid, Spain; (E.M.d.C.); (L.M.C.)
| | | | | | - Alfredo Guéra
- Department of Life Sciences, Universidad de Alcalá, Alcalá de Henares, 28802 Madrid, Spain; (E.M.d.C.); (L.M.C.)
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6
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Wang CH, Hou R, Wang M, He G, Li BG, Pan RL. Effects of wet atmospheric nitrogen deposition on epiphytic lichens in the subtropical forests of Central China: Evaluation of the lichen food supply and quality of two endangered primates. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 190:110128. [PMID: 31891838 DOI: 10.1016/j.ecoenv.2019.110128] [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: 10/18/2019] [Revised: 12/18/2019] [Accepted: 12/21/2019] [Indexed: 06/10/2023]
Abstract
Over the last few decades, the threat posed to biodiversity and ecosystem function by atmospheric nitrogen (N) deposition has been increasingly recognized. The disturbed nutrient balance and species composition of plants induced by higher N deposition can impact the biodiversity of the organisms that consume the plants. In this research, we implemented several experiments to estimate the effects of increased N deposition on the growth, survival, and nutrients of the dominant epiphytic lichens in the subtropical mountains in Central China to assess the lichen food amount and nutritional quality for two endangered primates endemic to China. Our results indicated that the thallus growth and propagule survival of the lichens were significantly decreased when nitrogen addition changed from 6.25 to 50.0 kg N·ha-1·y-1; it was also shown that lichen biomass could be decreased by 11.2%-70.2% when the deposition addition exceeded 6.25 kg N·ha-1·y-1. Further, our study revealed that increased nitrogen deposition also reduced the nutritional quality of the lichens via reducing the soluble protein and soluble sugar levels and increasing the fiber content, which would substantially affect the diet selection of the plants consumers in the region, particularly the populations of the two lichen-eating endangered primate species, Rhinopithecus roxellana and R. bieti. Our experimental study suggested that the nitrogen pollution derived from anthropogenic activities could cause cascading effects for the whole forest ecosystem of Central China; thus, more studies about nitrogen deposition in this region are required.
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Affiliation(s)
- C H Wang
- Engineering Research Centre of Eco-Environment in the Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Daxue Road 8th, Yichang, Hubei Province, 443002, PR China; Hubei International Scientific and Technological Cooperation Centre of Ecological Protection and Management in the Three Gorges Area, China Three Gorges University, Daxue Road 8th, Yichang, Hubei Province, 443002, PR China.
| | - R Hou
- Department of Anthropology, McGill University, Montreal, QC, H3A 2T7, Canada; Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, PR China
| | - M Wang
- Engineering Research Centre of Eco-Environment in the Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Daxue Road 8th, Yichang, Hubei Province, 443002, PR China
| | - G He
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, PR China
| | - B G Li
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, PR China; Xi'an Branch of Chinese Academy of Sciences, Xi'an, 710043, PR China
| | - R L Pan
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710069, PR China; School of Human Sciences and Centre for Evolutionary Biology, School of Biological Sciences, The University of Western Australia, Perth, WA, 6009, Australia
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7
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Wang M, Wang C, Jia R. The impact of nitrogen deposition on photobiont-mycobiont balance of epiphytic lichens in subtropical forests of central China. Ecol Evol 2019; 9:13468-13476. [PMID: 31871658 PMCID: PMC6912883 DOI: 10.1002/ece3.5803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/25/2019] [Accepted: 10/10/2019] [Indexed: 11/25/2022] Open
Abstract
Excessive nitrogen (N) deposition can impact lichen diversity in forest ecosystems, and this is a particular situation in China. Here, we examined the N uptake, assimilation, and the impact of excessive N deposition on the symbiotic balance of dominant epiphytic lichens in the subtropical forests in the Mts. Shennongjia of central China. The results show that lichen species took up, assimilated and utilized more ammonium than nitrate in a species-specific way, following the increase of N availability. The photobiont of the lichens decreased with the increase of N concentration following an initial increase, while the mycobiont response to the N addition was not apparent. Considerable variation in response to excessive N deposition exists among the lichen species. Usnea longissima could regulate its N uptake, resulting in a stable photobiont-mycobiont ratio among N treatments. In contrast, the photobiont-mycobiont ratio of other four lichens increased initially but decreased when N concentration exceeded a certain level, and N stress may have broken the balance between photobiont and mycobiont of these lichens. Our results suggest that most epiphytic lichens in subtropical forest of central China could uptake and assimilate more ammonium than nitrate and that the balance between photobiont and mycobiont of many epiphytic lichens might change with the increasing N deposition load, which could impact the lichen diversity of this forest ecosystem.
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Affiliation(s)
- Ming Wang
- Engineering Research Center of Eco‐environment in Three Gorges Reservoir RegionMinistry of EducationChina Three Gorges UniversityYichangChina
- Hubei International Scientific and Technological Cooperation Center of Ecological Protection and Management in the Three Gorges AreaChina Three Gorges UniversityYichangChina
| | - Chuanhua Wang
- Engineering Research Center of Eco‐environment in Three Gorges Reservoir RegionMinistry of EducationChina Three Gorges UniversityYichangChina
- Hubei International Scientific and Technological Cooperation Center of Ecological Protection and Management in the Three Gorges AreaChina Three Gorges UniversityYichangChina
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8
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Hoffman AS, Albeke SE, McMurray JA, Evans RD, Williams DG. Nitrogen deposition sources and patterns in the Greater Yellowstone Ecosystem determined from ion exchange resin collectors, lichens, and isotopes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 683:709-718. [PMID: 31150891 DOI: 10.1016/j.scitotenv.2019.05.323] [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: 12/30/2018] [Revised: 05/20/2019] [Accepted: 05/21/2019] [Indexed: 05/16/2023]
Abstract
Over the past century, atmospheric nitrogen deposition (Ndep) has increased across the western United States due to agricultural and urban development, resulting in degraded ecosystem quality. Regional patterns of Ndep are often estimated by coupling direct measurements from large-scale monitoring networks and atmospheric chemistry models, but such efforts can be problematic in the western US because of complex terrain and sparse sampling. This study aimed not only to understand Ndep patterns in mountainous ecosystems but also to investigate whether isotope values of lichens and throughfall deposition can be used to determine Ndep sources, and serve as an additional tool in ecosystem health assessments. We measured Ndep amounts and δ15N in montane conifer forests of the Greater Yellowstone Ecosystem using canopy throughfall and bulk monitors and lichens. In addition, we examined patterns of C:N ratios in lichens as a possible indicator of lichen physiological condition. The isotopic signature of δ15N of Ndep helps to discern emission sources, because δ15N of NOx from combustion tends to be high (-5 to +25‰) while NHx from agricultural sources tends to be comparatively low (-40 to -10‰). Summertime Ndep increased with elevation and ranged from 0.26 to 1.66 kg ha-1. Ndep was higher than expected in remote areas. The δ15N values of lichens were typically -15.3 to -10‰ suggesting agriculture as a primary emission source of deposition. Lichen %N, δ15N and C:N ratios can provide important information about Ndep sources and patterns over small spatial scales in complex terrain.
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Affiliation(s)
| | - Shannon E Albeke
- University of Wyoming, Laramie, WY 82071, United States of America
| | - Jill A McMurray
- Bridger Teton National Forest, United States Forest Service, Pinedale, WY 82941, United States of America
| | - R David Evans
- School of Biological Sciences, Washington State University, Pullman, WA 99164, United States of America
| | - David G Williams
- University of Wyoming, Laramie, WY 82071, United States of America
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9
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Gutiérrez-Larruga B, Estébanez-Pérez B, Ochoa-Hueso R. Effects of Nitrogen Deposition on the Abundance and Metabolism of Lichens: A Meta-analysis. Ecosystems 2019. [DOI: 10.1007/s10021-019-00431-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Manninen S. Deriving nitrogen critical levels and loads based on the responses of acidophytic lichen communities on boreal urban Pinus sylvestris trunks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 613-614:751-762. [PMID: 28938217 DOI: 10.1016/j.scitotenv.2017.09.150] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 08/29/2017] [Accepted: 09/15/2017] [Indexed: 06/07/2023]
Abstract
The deposition of reactive nitrogen (N) compounds currently predominates over sulphur (S) deposition in most of the cities in Europe and North America. Acidophytic lichens growing on tree trunks are known to be sensitive to both N and S deposition. Given that tree species and climatic factors affect the composition of epiphytic lichen communities and modify lichen responses to air pollution, this study focused on the impact of urban air pollution on acidophytes growing on boreal conifer trunks. The study was performed in the Helsinki metropolitan area, southern Finland, where annual mean nitrogen dioxide (NO2) concentrations range from 4-5μgm-3 to >50μgm-3. In addition, background forest sites in southern and northern Finland were included. The results demonstrated elevated N contents (≥0.7%) in Hypogymnia physodes and Platismatia glauca at all the sites where the species occurred. In the Helsinki metropolitan area, a higher frequency of green algae+Scoliociosporum chlorococcum and reduced numerical frequencies of other indicator lichen species (e.g. Pseudevernia furfuracea, Bryoria spp., Usnea spp.) were associated with elevated atmospheric concentrations of NO2 and particulate matter containing N, as well as elevated concentrations of inorganic N in bark. The N isotope values (δ15N) of lichens supported the uptake of oxidized N mainly originating from road traffic. Sulphur dioxide (SO2) also negatively affected the most sensitive species, despite the current low levels (1-4μgm-3yr-1). Critical levels of 5μgNO2m-3yr-1 and 0.5μgNH3m-3yr-1, and a critical load of 2-3kgNha-1yr-1 are proposed for protecting the diversity of boreal acidophytes. This study calls for measurements of the throughfall of various N fractions in urban forest ecosystems along precipitation and temperature gradients to verify the proposed critical levels and loads.
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Affiliation(s)
- Sirkku Manninen
- Department of Environmental Sciences, University of Helsinki, P.O. Box 65, Viikinkaari 2a, 00014 Helsinki, Finland.
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11
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Palmqvist K, Franklin O, Näsholm T. Symbiosis constraints: Strong mycobiont control limits nutrient response in lichens. Ecol Evol 2017; 7:7420-7433. [PMID: 28944027 PMCID: PMC5606882 DOI: 10.1002/ece3.3257] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 06/15/2017] [Accepted: 06/28/2017] [Indexed: 11/07/2022] Open
Abstract
Symbioses such as lichens are potentially threatened by drastic environmental changes. We used the lichen Peltigera aphthosa-a symbiosis between a fungus (mycobiont), a green alga (Coccomyxa sp.), and N2-fixing cyanobacteria (Nostoc sp.)-as a model organism to assess the effects of environmental perturbations in nitrogen (N) or phosphorus (P). Growth, carbon (C) and N stable isotopes, CNP concentrations, and specific markers were analyzed in whole thalli and the partners after 4 months of daily nutrient additions in the field. Thallus N was 40% higher in N-fertilized thalli, amino acid concentrations were twice as high, while fungal chitin but not ergosterol was lower. Nitrogen also resulted in a thicker algal layer and density, and a higher δ13C abundance in all three partners. Photosynthesis was not affected by either N or P. Thallus growth increased with light dose independent of fertilization regime. We conclude that faster algal growth compared to fungal lead to increased competition for light and CO 2 among the Coccomyxa cells, and for C between alga and fungus, resulting in neither photosynthesis nor thallus growth responded to N fertilization. This suggests that the symbiotic lifestyle of lichens may prevent them from utilizing nutrient abundance to increase C assimilation and growth.
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Affiliation(s)
- Kristin Palmqvist
- Department of Ecology and Environmental Science (EMG)Umeå UniversityUmeåSweden
| | - Oskar Franklin
- International Institute for Applied Systems Analysis (IIASA)LaxenburgAustria
| | - Torgny Näsholm
- Department of Forest Ecology and ManagementSwedish University of Agriculture Sciences (SLU)UmeåSweden
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12
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Scalise A, Pappa VA, Gelsomino A, Rees RM. Pea cultivar and wheat residues affect carbon/nitrogen dynamics in pea-triticale intercropping: A microcosms approach. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 592:436-450. [PMID: 28340454 DOI: 10.1016/j.scitotenv.2017.03.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 03/02/2017] [Accepted: 03/02/2017] [Indexed: 06/06/2023]
Abstract
The underlying mechanisms by which legume cultivars contribute to nitrous oxide (N2O) generation are poorly understood. The aim of the present study was to explore the effects of two pea cultivars (Zero4 and Nitouche) intercropped with triticale, with or without wheat (Triticum aestivum) residues incorporation, on soil C and N dynamics, on bacterial community structure and their links with N2O emissions. Monocrops and bare soil (no plant) treatments were used as an additional control in order to account for the level of mineralisation between treatments. Changes in total C and N contents and in some functionally-related soil pools (microbial biomass C and N, basal respiration, KCl-exchangeable ammonium and nitrate, potentially mineralisable N, DOC, ecophysiological indexes) were followed throughout a 97-day microcosm experiment carried out on a loamy arable soil. ARISA community fingerprinting of soil extracted DNA and GHG emissions were carried out at two key stages (pea flowering and harvest). The addition of residues to the soil resulted in only small changes to the total C and N pools the Nitouche monocrop, which was found to have the highest potentially mineralisable N (13.4μgg-128d-1) of the treatments with added residue. The different pea cultivar selectively affected N2O emissions, with highest emissions associated with the cultivar Nitouche in the absence of residues. The two intercropping treatments of triticale/pea were significantly different either with residues or without, especially the triticale/Zero4 which had the lowest values (356gN2O-Nha-1). Similar patterns were also observed in below ground data. ARISA analysis showed that monocropped legumes and the Triticale-based treatment clearly grouped on separate clusters to the added residue treatment. We hypothesize that in pea-based intercrops variations in carbon supply from different cultivars may contribute to differences in N2O emissions and thus influence the choice of suitable cultivars, to optimize nutrient cycling and sustainable crop management.
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Affiliation(s)
- Antonella Scalise
- Mediterranean University of Reggio Calabria, Department of Agricultural Sciences, Feo di 10 Vito, I-89124 Reggio Calabria, Italy.
| | - Valentini A Pappa
- SRUC, West Mains Road, Edinburgh EH9 3JG, United Kingdom; Texas A&M University, Energy Institute, 302 Williams Administration Building, College Station, TX 77843, USA
| | - Antonio Gelsomino
- Mediterranean University of Reggio Calabria, Department of Agricultural Sciences, Feo di 10 Vito, I-89124 Reggio Calabria, Italy
| | - Robert M Rees
- SRUC, West Mains Road, Edinburgh EH9 3JG, United Kingdom
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Carter TS, Clark CM, Fenn ME, Jovan S, Perakis SS, Riddell J, Schaberg PG, Greaver TL, Hastings MG. Mechanisms of nitrogen deposition effects on temperate forest lichens and trees. Ecosphere 2017; 8:10.1002/ecs2.1717. [PMID: 34327038 PMCID: PMC8318115 DOI: 10.1002/ecs2.1717] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We review the mechanisms of deleterious nitrogen (N) deposition impacts on temperate forests, with a particular focus on trees and lichens. Elevated anthropogenic N deposition to forests has varied effects on individual organisms depending on characteristics both of the N inputs (form, timing, amount) and of the organisms (ecology, physiology) involved. Improved mechanistic knowledge of these effects can aid in developing robust predictions of how organisms respond to either increases or decreases in N deposition. Rising N levels affect forests in micro- and macroscopic ways from physiological responses at the cellular, tissue, and organism levels to influencing individual species and entire communities and ecosystems. A synthesis of these processes forms the basis for the overarching themes of this paper, which focuses on N effects at different levels of biological organization in temperate forests. For lichens, the mechanisms of direct effects of N are relatively well known at cellular, organismal, and community levels, though interactions of N with other stressors merit further research. For trees, effects of N deposition are better understood for N as an acidifying agent than as a nutrient; in both cases, the impacts can reflect direct effects on short time scales and indirect effects mediated through long-term soil and belowground changes. There are many gaps on fundamental N use and cycling in ecosystems, and we highlight the most critical gaps for understanding potential deleterious effects of N deposition. For lichens, these gaps include both how N affects specific metabolic pathways and how N is metabolized. For trees, these gaps include understanding the direct effects of N deposition onto forest canopies, the sensitivity of different tree species and mycorrhizal symbionts to N, the influence of soil properties, and the reversibility of N and acidification effects on plants and soils. Continued study of how these N response mechanisms interact with one another, and with other dimensions of global change, remains essential for predicting ongoing changes in lichen and tree populations across North American temperate forests.
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Affiliation(s)
- Therese S. Carter
- US Global Change Research Program, ICF Contractor, 1800 G Street NW, Suite 9100, Washington, D.C. 20006 USA
- Department of Chemistry, Brown University, 324 Brook Street, Providence, Rhode Island 02912 USA
| | - Christopher M. Clark
- US EPA, Office of Research and Development, Global Change Research Group, 1200 Pennsylvania Avenue, N. W., Washington, D.C. 20460 USA
| | - Mark E. Fenn
- USDA Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Drive, Riverside, California 92507 USA
| | - Sarah Jovan
- USDA Forest Service, Pacific Northwest Research Station, 620 SW Main Street, Portland, Oregon 97205 USA
| | - Steven S. Perakis
- US Geological Survey, Forest and Rangeland Ecosystem Science Center, Corvallis, Oregon 97331 USA
| | - Jennifer Riddell
- Sustainable Technology Program, Mendocino College, 1000 Hensley Creek Road, Ukiah, California 95482 USA
| | - Paul G. Schaberg
- USDA Forest Service, Northern Research Station, 705 Spear Street S, Burlington, Vermont 05405 USA
| | - Tara L. Greaver
- National Center for Environmental Assessment, US Environmental Protection Agency, Research Triangle Park, North Carolina 27711 USA
| | - Meredith G. Hastings
- Department of Earth, Environmental, and Planetary Sciences, Institute at Brown for Environment and Society, Brown University, 324 Brook Street, Providence, Rhode Island 02912 USA
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Asplund J, Johansson O, Nybakken L, Palmqvist K, Gauslaa Y. Simulated nitrogen deposition influences gastropod grazing in lichens. ECOSCIENCE 2015. [DOI: 10.2980/17-1-3331] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Alam MA, Gauslaa Y, Solhaug KA. Soluble carbohydrates and relative growth rates in chloro-, cyano- and cephalolichens: effects of temperature and nocturnal hydration. THE NEW PHYTOLOGIST 2015; 208:750-62. [PMID: 26017819 DOI: 10.1111/nph.13484] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 05/05/2015] [Indexed: 05/15/2023]
Abstract
This growth chamber experiment evaluates how temperature and humidity regimes shape soluble carbohydrate pools and growth rates in lichens with different photobionts. We assessed soluble carbohydrates, relative growth rates (RGRs) and relative thallus area growth rates (RTA GRs) in Parmelia sulcata (chlorolichen), Peltigera canina (cyanolichen) and Peltigera aphthosa (cephalolichen) cultivated for 14 d (150 μmol m(-2) s(-1) ; 12-h photoperiod) at four day : night temperatures (28 : 23°C, 20 : 15°C, 13 : 8°C, 6 : 1°C) and two hydration regimes (hydration during the day, dry at night; hydration day : night). The major carbohydrates were mannitol (cephalolichen), glucose (cyanolichen) and arabitol (chlorolichen). Mannitol occurred in all species. During cultivation, total carbohydrate pools decreased in cephalo-/cyanolichens, but increased in the chlorolichen. Carbohydrates varied less than growth with temperature and humidity. All lichens grew rapidly, particularly at 13 : 8°C. RGRs and RTA GRs were significantly higher in lichens hydrated for 24 h than for 12 h. Strong photoinhibition occurred in cephalo- and cyanolichens kept in cool dry nights, resulting in positive relationships between RGR and dark-adapted photosystem II (PSII) efficiency (Fv /Fm ). RGR increased significantly with the photobiont-specific carbohydrate pools within all species. Average RGR peaked in the chlorolichen lowest in total and photobiont carbohydrates. Nocturnal hydration improved recovery from photoinhibition and/or enhanced conversion rates of photosynthates into growth.
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Affiliation(s)
- Md Azharul Alam
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432, Ås, Norway
| | - Yngvar Gauslaa
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432, Ås, Norway
| | - Knut Asbjørn Solhaug
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, PO Box 5003, NO-1432, Ås, Norway
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Differential effects of lichens versus liverworts epiphylls on host leaf traits in the tropical montane rainforest, Hainan Island, China. ScientificWorldJournal 2014; 2014:681369. [PMID: 25003144 PMCID: PMC4066865 DOI: 10.1155/2014/681369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 04/28/2014] [Indexed: 11/17/2022] Open
Abstract
Epiphylls widely colonize vascular leaves in moist tropical forests.
Understanding the effects of epiphylls on leaf traits of host plants is critical for understanding ecological function of epiphylls.
A study was conducted in a rain forest to investigate leaf traits of the host plants Photinia prunifolia
colonized with epiphyllous liverworts and foliicolous lichens as well as those of uncolonized leaves.
Our results found that the colonization of lichens significantly decreased leaf water content (LWC),
chlorophyll (Chl) a and a + b content,
and Chl a/b of P. prunifolia but increased Chl b content,
while that of liverworts did not affect them as a whole.
The variations of net photosynthetic rates (Pn) among host leaves colonized with different coverage of lichens before or
after removal treatment (a treatment to remove epiphylls from leaf surface) were greater than that colonized with liverworts.
The full cover of lichens induced an increase of light compensation point (LCP) by 21%
and a decrease of light saturation point (LSP) by 54% for their host leaves, whereas that of liverworts displayed contrary effects.
Compared with the colonization of liverworts,
lichens exhibited more negative effects on the leaf traits of P. prunifolia in different stages of colonization.
The results suggest that the responses of host leaf traits to epiphylls are affected by the epiphyllous groups and coverage,
which are also crucial factors in assessing ecofunctions of epiphylls in tropical forests.
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Boltersdorf SH, Pesch R, Werner W. Comparative use of lichens, mosses and tree bark to evaluate nitrogen deposition in Germany. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2014; 189:43-53. [PMID: 24631972 DOI: 10.1016/j.envpol.2014.02.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 02/13/2014] [Accepted: 02/15/2014] [Indexed: 06/03/2023]
Abstract
To compare three biomonitoring techniques for assessing nitrogen (N) pollution in Germany, 326 lichen, 153 moss and 187 bark samples were collected from 16 sites of the national N deposition monitoring network. The analysed ranges of N content of all investigated biomonitors (0.32%-4.69%) and the detected δ(15)N values (-15.2‰-1.5‰), made it possible to reveal species specific spatial patterns of N concentrations in biota to indicate atmospheric N deposition in Germany. The comparison with measured and modelled N deposition data shows that particularly lichens are able to reflect the local N deposition originating from agriculture.
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Affiliation(s)
| | - Roland Pesch
- Chair of Landscape Ecology, University of Vechta, PO Box 1553, D-49356 Vechta, Germany.
| | - Willy Werner
- Department of Geobotany, University of Trier, Behringstr. 21, D-54296 Trier, Germany.
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Jovan S, Riddell J, Padgett PE, Nash TH. Eutrophic lichens respond to multiple forms of N: implications for critical levels and critical loads research. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2012; 22:1910-1922. [PMID: 23210308 DOI: 10.1890/11-2075.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Epiphytic lichen communities are highly sensitive to excess nitrogen (N), which causes the replacement of native floras by N-tolerant, "weedy" eutrophic species. This shift is commonly used as the indicator of ecosystem "harm" in studies developing empirical critical levels (CLE) for ammonia (NH3) and critical loads (CLO) for N. To be most effective, empirical CLE and/or CLO must firmly link lichen response to causal pollutant(s), which is difficult to accomplish in field studies in part because the high cost of N measurements limits their use. For this case study we synthesized an unprecedented array of atmospheric N measurements across 22 long-term monitoring sites in the Los Angeles Basin, California, USA: gas concentrations of NH3, nitric acid (HNO3), nitrogen dioxide, and ozone (n = 10 sites); N deposition in throughfall (n = 8 sites); modeled estimates of eight different forms of N (n = 22 sites); and nitrate deposition accumulated on oak twigs (n = 22 sites). We sampled lichens on black oak (Quercus kelloggii Newb.), and scored plots using two indices of eutroph (N tolerant species) abundance to characterize the community-level response to N. Our results contradict two common assertions about the lichen-N response: (1) that eutrophs respond specifically to NH3 and (2) that the response necessarily depends upon the increased pH of lichen substrates. Eutroph abundance related significantly but weakly to NH3 (r2 = 0.48). Total N deposition as measured in canopy throughfall was by far the best predictor of eutroph abundance (r2 = 0.94), indicating that eutrophs respond to multiple forms of N. Most N variables had significant correlations to eutroph abundance (r2 = 0.36-0.62) as well as to each other (r2 = 0.61-0.98), demonstrating the risk of mistaken causality in CLE/CLO field studies that lack sufficient calibration data. Our data furthermore suggest that eutroph abundance is primarily driven by N inputs, not substrate pH, at least at the high-pH values found in the basin (4.8-6.1). Eutroph abundance correlated negatively with trunk bark pH (r2 = 0.43), exactly the opposite of virtually all previous studies of eutroph behavior. This correlation probably results because HNO3 dominates N deposition in our study region.
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Affiliation(s)
- Sarah Jovan
- Forest Inventory and Analysis Program, USDA Forest Service, Portland Forestry Sciences Laboratory, 620 SW Main Street, Suite 400, Portland, Oregon 97205, USA.
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Hauck M, Otto PI, Dittrich S, Jacob M, Bade C, Dörfler I, Leuschner C. Small increase in substratum [corrected] pH causes the dieback of one of Europe's most common lichens, Lecanora conizaeoides. ANNALS OF BOTANY 2011; 108:359-66. [PMID: 21788378 PMCID: PMC3143046 DOI: 10.1093/aob/mcr136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Accepted: 04/18/2011] [Indexed: 05/24/2023]
Abstract
BACKGROUNDS AND AIMS Lecanora conizaeoides was until recently western and central Europe's most abundant epiphytic lichen species or at least one of the most common epiphytes. The species is adapted to very acidic conditions at pH values around 3 and high concentrations of SO(2) and its derivatives formed in aqueous solution, and thus spread with increasing SO(2) deposition during the 19th and 20th centuries. With the recent decrease of SO(2) emissions to nearly pre-industrial levels within 20 years, L. conizaeoides declined from most of its former range. If still present, the species is no longer the dominant epiphyte, but is occurring in small densities only. The rapid spread of the L. conizaeoides in Europe from an extremely rare species to the probably most frequent epiphytic lichen and the subsequent rapid dieback are unprecedented by any other organism. The present study aimed at identifying the magnitude of deacidification needed to cause the dieback of the lichen. METHODS The epiphytic lichen diversity and bark chemistry of montane spruce forests in the Harz Mountains, northern Germany, were studied and the results were compared with data recorded with the same methods 13-15 years ago. KEY RESULTS Lecanora conizaeoides, which was the dominant epiphyte of the study area until 15 years ago, is still found on most trees, but only with small cover values of ≤1 %. The bark pH increased by only 0·4 pH units. CONCLUSIONS The data suggest that only slight deacidification of the substratum causes the breakdown of the L. conizaeoides populations. Neither competitors nor parasites of L. conizaeoides that may have profited from reduced SO(2) concentrations are likely causes of the rapid dieback of the species.
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Affiliation(s)
- Markus Hauck
- Department of Plant Ecology, Albrecht von Haller Institute of Plant Sciences, University of Göttingen, Untere Karspüle 2, D-37073 Göttingen, Germany.
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Johansson O, Olofsson J, Giesler R, Palmqvist K. Lichen responses to nitrogen and phosphorus additions can be explained by the different symbiont responses. THE NEW PHYTOLOGIST 2011; 191:795-805. [PMID: 21534972 DOI: 10.1111/j.1469-8137.2011.03739.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
• Responses to simulated nitrogen (N) deposition with or without added phosphorus (P) were investigated for three contrasting lichen species - the N-sensitive Alectoria sarmentosa, the more N-tolerant Platismatia glauca and the N(2) -fixing Lobaria pulmonaria- in a field experiment. • To examine whether nutrient limitation differed between the photobiont and the mycobiont within the lichen, the biomass responses of the respective bionts were estimated. • The lichenized algal cells were generally N-limited, because N-stimulated algal growth in all three species. The mycobiont was P-limited in one species (A. sarmentosa), but the growth response of the mycobionts was complex, as fungal growth is also dependent on a reliable carbon export from the photobiont, which may have been the reason for the decrease of the mycobiont with N addition in P. glauca. • Our findings showed that P availability was an important factor when studying effects of N deposition, as P supply can both mitigate and intensify the negative effects of N on epiphytic lichens.
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Affiliation(s)
- Otilia Johansson
- Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden
| | - Johan Olofsson
- Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden
| | - Reiner Giesler
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, SE-981 07 Abisko, Sweden
| | - Kristin Palmqvist
- Department of Ecology and Environmental Science, Umeå University, SE-901 87 Umeå, Sweden
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22
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Stevens CJ, Manning P, van den Berg LJL, de Graaf MCC, Wamelink GWW, Boxman AW, Bleeker A, Vergeer P, Arroniz-Crespo M, Limpens J, Lamers LPM, Bobbink R, Dorland E. Ecosystem responses to reduced and oxidised nitrogen inputs in European terrestrial habitats. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:665-76. [PMID: 21215502 DOI: 10.1016/j.envpol.2010.12.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2010] [Revised: 11/29/2010] [Accepted: 12/09/2010] [Indexed: 05/06/2023]
Abstract
While it is well established that ecosystems display strong responses to elevated nitrogen deposition, the importance of the ratio between the dominant forms of deposited nitrogen (NH(x) and NO(y)) in determining ecosystem response is poorly understood. As large changes in the ratio of oxidised and reduced nitrogen inputs are occurring, this oversight requires attention. One reason for this knowledge gap is that plants experience a different NH(x):NO(y) ratio in soil to that seen in atmospheric deposits because atmospheric inputs are modified by soil transformations, mediated by soil pH. Consequently species of neutral and alkaline habitats are less likely to encounter high NH(4)(+) concentrations than species from acid soils. We suggest that the response of vascular plant species to changing ratios of NH(x):NO(y) deposits will be driven primarily by a combination of soil pH and nitrification rates. Testing this hypothesis requires a combination of experimental and survey work in a range of systems.
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Affiliation(s)
- Carly J Stevens
- Department of Life Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK.
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Ochoa-Hueso R, Manrique E. Effects of nitrogen deposition and soil fertility on cover and physiology of Cladonia foliacea (Huds.) Willd., a lichen of biological soil crusts from Mediterranean Spain. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:449-457. [PMID: 21071125 DOI: 10.1016/j.envpol.2010.10.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2010] [Revised: 10/04/2010] [Accepted: 10/15/2010] [Indexed: 05/30/2023]
Abstract
We are fertilizing a thicket with 0, 10, 20 and 50 kg nitrogen (N) ha(-1) yr(-1) in central Spain. Here we report changes in cover, pigments, pigment ratios and FvFm of the N-tolerant, terricolous, lichen Cladonia foliacea after 1-2 y adding N in order to study its potential as biomarker of atmospheric pollution. Cover tended to increase. Pigments increased with fertilization independently of the dose supplied but only significantly with soil nitrate as covariate. β-carotene/chlorophylls increased with 20-50 kg N ha(-1) yr(-1) (over the background) and neoxanthin/chlorophylls also increased with N. (Neoxanthin+lutein)/carotene decreased with N when nitrate and pH seasonalities were used as covariates. Between 26 and 56 kg N ha(-1) yr(-1).Pinho et al. (2012) suggested that the critical Nload for Mediterranean epiphytic lichens (based on responses of functional groups) was lower than 26 kg N ha(-1) yr(-1) [corrected]. Water-stress, iron and copper also explained variables of lichen physiology. We conclude that this tolerant lichen could be used as biomarker and that responses to N are complex in heterogeneous Mediterranean-type landscapes.
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Affiliation(s)
- Raúl Ochoa-Hueso
- Instituto de Recursos Naturales, Centro de Ciencias Medioambientales, Consejo Superior de Investigaciones Científicas, C/Serrano 115 bis, 28006 Madrid, Spain.
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Johansson O, Nordin A, Olofsson J, Palmqvist K. Responses of epiphytic lichens to an experimental whole-tree nitrogen-deposition gradient. THE NEW PHYTOLOGIST 2010; 188:1075-1084. [PMID: 20731782 DOI: 10.1111/j.1469-8137.2010.03426.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Here, we examined the responses of the epiphytic lichens Alectoria sarmentosa and Platismatia glauca to increased atmospheric nitrogen (N) deposition in an old-growth boreal spruce forest, to assess the sensitivity of these species to N and define their critical N load. Nitrogen deposition was simulated by irrigating 15 trees over a 3 yr period with water and isotopically labeled NH(4)NO(3), providing N loads ranging from ambient to 50 kg N ha(-1) yr(-1) . Thallus N concentration increased in both species with increasing N load, and uptake rates of both NH(4)(+) and NO(3)(-) were similar. Photobiont concentration increased linearly with increased N in both species, saturating in A. sarmentosa in the third year at the highest N loads (25 and 50 kg ha(-1) yr(-1)). The simulated N deposition decreased the phosphorus (P) concentration in A. sarmentosa, and increased the N:P ratio in both species. Significant responses in lichen chemistry were detected to inputs of 12.5 kg N ha(-1) yr(-1) or higher, suggesting that resources other than N limit lichens at higher N loads. However, the data also suggest that N saturation may be cumulative over time, even at low N.
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Affiliation(s)
- Otilia Johansson
- Department of Ecology and Environmental Science (EMG), Umeå University, SE-901 87 Umeå, Sweden.
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Britton AJ, Fisher JM. Terricolous alpine lichens are sensitive to both load and concentration of applied nitrogen and have potential as bioindicators of nitrogen deposition. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2010; 158:1296-1302. [PMID: 20149506 DOI: 10.1016/j.envpol.2010.01.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 01/18/2010] [Accepted: 01/20/2010] [Indexed: 05/28/2023]
Abstract
The influence of applied nitrogen (N) concentration and load on thallus chemistry and growth of five terricolous alpine lichen species was investigated in a three-month N addition study. Thallus N content was influenced by both concentration and load; but the relative importance of these parameters varied between species. Growth was most affected by concentration. Thresholds for effects observed in this study support a low critical load for terricolous lichen communities (<7.5 kg N ha(-1) y(-1)) and suggest that concentrations of N currently encountered in UK cloudwater may have detrimental effects on the growth of sensitive species. The significance of N concentration effects on sensitive species also highlights the need to avoid artificially high concentrations when designing N addition experiments. Given the sensitivity of some species to extremely low loads and concentrations of N we suggest that terricolous lichens have potential as indicators of deposition and impact in northern and alpine ecosystems.
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Affiliation(s)
- Andrea J Britton
- Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8QH, UK.
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Hauck M. Ammonium and nitrate tolerance in lichens. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2010; 158:1127-1133. [PMID: 20096494 DOI: 10.1016/j.envpol.2009.12.036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2009] [Revised: 11/21/2009] [Accepted: 12/22/2009] [Indexed: 05/28/2023]
Abstract
Since lichens lack roots and take up water, solutes and gases over the entire thallus surface, these organisms respond more sensitively to changes in atmospheric purity than vascular plants. After centuries where effects of sulphur dioxide and acidity were in the focus of research on atmospheric chemistry and lichens, recently the globally increased levels of ammonia and nitrate increasingly affect lichen vegetation and gave rise to intense research on the tolerance of lichens to nitrogen pollution. The present paper discusses the main findings on the uptake of ammonia and nitrate in the lichen symbiosis and to the tolerance of lichens to eutrophication. Ammonia and nitrate are both efficiently taken up under ambient conditions. The tolerance to high nitrogen levels depends, among others, on the capability of the photobiont to provide sufficient amounts of carbon skeletons for ammonia assimilation. Lowly productive lichens are apparently predisposed to be sensitive to excess nitrogen.
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Affiliation(s)
- Markus Hauck
- Department of Plant Ecology, Albrecht von Haller Institute of Plant Sciences, University of Göttingen, Untere Karspüle 2, 37073 Göttingen, Germany.
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Kytöviita MM, Crittenden PD. Growth and nitrogen relations in the mat-forming lichens Stereocaulon paschale and Cladonia stellaris. ANNALS OF BOTANY 2007; 100:1537-45. [PMID: 17951586 PMCID: PMC2759231 DOI: 10.1093/aob/mcm249] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2007] [Revised: 04/20/2007] [Accepted: 08/14/2007] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS Mat-forming lichens in the genera Stereocaulon and Cladonia have ecosystem-level effects in northern boreal forests. Yet the factors affecting the productivity of mat-forming lichens are not known. The aim of the presented work was to investigate whether mat-forming lichens adapted to low N availability employ N-conserving mechanisms similar to those of vascular plants in nutrient-poor ecosystems. Specifically, the following questions were asked: (a) Do lichens translocate N from basal areas to apical growth areas? (b) Are the quantities of N translocated of ecological significance. (c) Is lichen growth dependent on tissue N concentration [N]. METHODS Two different, but complementary, field experiments were conducted using the mat-forming N2-fixing Stereocaulon paschale and non-fixing Cladonia stellaris as model species. First, N translocation was investigated by feeding lichens with Na(15)NO3 either directly to the apex (theoretical sink) or to the basal part (theoretical source) and observing the redistribution of (15)N after a growth period. Secondly, growth and variation in [N] in thalli of different lengths was measured after a growth period. KEY RESULTS (15)N fed to lower parts of lichen was translocated towards the growing top, but not vice versa, indicating physiologically dependent translocation that follows a sink-source relationship. In the growth experiment where thalli were cut to different lengths, the significant decrease in [N] in apices of short vs. longer thalli after a growth period is consistent with internal relocation as an ecologically important source of N. CONCLUSIONS The presented results demonstrate that internal recycling of N occurs in both species investigated and may be ecologically important in these mat-forming lichens under field conditions. The higher nitrogen use efficiency and relative growth rate in C. stellaris in comparison with S. paschale probably enable C. stellaris to dominate the ground cover vegetation in dry boreal coniferous forests under undisturbed conditions.
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Affiliation(s)
- M-M Kytöviita
- School of Biology, University of Nottingham, Nottingham NG7 2RD, UK.
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