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Zhao C, He X, Dan X, He M, Zhao J, Meng H, Cai Z, Zhang J. Soil dissolved organic matters mediate bacterial taxa to enhance nitrification rates under wheat cultivation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 828:154418. [PMID: 35276137 DOI: 10.1016/j.scitotenv.2022.154418] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/04/2022] [Accepted: 03/05/2022] [Indexed: 06/14/2023]
Abstract
Studies have shown that dissolved organic matters (DOMs) may affect soil nutrient availability to plants due to their effect on microbial communities; however, the relationships of soil DOM-bacterial community-N function in response to root exudates remains poorly understand. Here, we evaluated the DOM composition, bacterial taxonomic variation and nitrogen transformation rates in both acidic and alkaline soils, with or without the typical nitrate preference plant (wheat, Triticum aestivum L.). After 30 days' cultivation, DOM compositions such as sugars, amines, amino acids, organic acid, and ketone were significantly increased in soil with wheat vs. bare soil, and these compounds were mainly involved in nitrogen metabolism pathways. Soil core bacterial abundance was changed while bacterial community diversity decreased in response to wheat planting. Function prediction analysis based on FAPROTAX software showed that the bacterial community were significantly (p < 0.05) affiliated with nitrification and organic compound degradation. Additionally, db-RDA and VPA analysis suggested that the contribution of soil DOM to the variance of bacterial community was stronger than that of soil available nutrients. Furthermore, the N-transformation related bacteria like Burkholderiales and ammonia-oxidizing bacteria (AOB) were positively correlated with soil gross nitrification rate, confirming that the soil N transformation was enhanced in both acidic and alkaline soils. Our results provide insight into how soil DOM affects the community structure and function of bacteria to regulate the process of nitrogen transformation in plant-soil system.
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Affiliation(s)
- Chang Zhao
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China
| | - Xiaoxiang He
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China
| | - Xiaoqian Dan
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China
| | - Mengqiu He
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China
| | - Jun Zhao
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource, Development and Application, Nanjing 210023, PR China
| | - Han Meng
- School of Environment, Nanjing Normal University, Nanjing 210023, PR China.
| | - Zucong Cai
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China; Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, PR China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource, Development and Application, Nanjing 210023, PR China
| | - Jinbo Zhang
- School of Geography, Nanjing Normal University, Nanjing 210023, PR China; Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, PR China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource, Development and Application, Nanjing 210023, PR China
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Abstract
Arid ecosystems cover ∼40% of the Earth's terrestrial surface and store a high proportion of the global nitrogen (N) pool. They are low-productivity, low-biomass, and polyextreme ecosystems, i.e., with (hyper)arid and (hyper)oligotrophic conditions and high surface UV irradiation and evapotranspiration. These polyextreme conditions severely limit the presence of macrofauna and -flora and, particularly, the growth and productivity of plant species. Therefore, it is generally recognized that much of the primary production (including N-input processes) and nutrient biogeochemical cycling (particularly N cycling) in these ecosystems are microbially mediated. Consequently, we present a comprehensive survey of the current state of knowledge of biotic and abiotic N-cycling processes of edaphic (i.e., open soil, biological soil crust, or plant-associated rhizosphere and rhizosheath) and hypo/endolithic refuge niches from drylands in general, including hot, cold, and polar desert ecosystems. We particularly focused on the microbially mediated biological nitrogen fixation, N mineralization, assimilatory and dissimilatory nitrate reduction, and nitrification N-input processes and the denitrification and anaerobic ammonium oxidation (anammox) N-loss processes. We note that the application of modern meta-omics and related methods has generated comprehensive data sets on the abundance, diversity, and ecology of the different N-cycling microbial guilds. However, it is worth mentioning that microbial N-cycling data from important deserts (e.g., Sahara) and quantitative rate data on N transformation processes from various desert niches are lacking or sparse. Filling this knowledge gap is particularly important, as climate change models often lack data on microbial activity and environmental microbial N-cycling communities can be key actors of climate change by producing or consuming nitrous oxide (N2O), a potent greenhouse gas.
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Water-driven microbial nitrogen transformations in biological soil crusts causing atmospheric nitrous acid and nitric oxide emissions. THE ISME JOURNAL 2022; 16:1012-1024. [PMID: 34764454 PMCID: PMC8941053 DOI: 10.1038/s41396-021-01127-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 09/16/2021] [Accepted: 09/22/2021] [Indexed: 01/12/2023]
Abstract
Biological soil crusts (biocrusts) release the reactive nitrogen gases (Nr) nitrous acid (HONO) and nitric oxide (NO) into the atmosphere, but the underlying microbial process controls have not yet been resolved. In this study, we analyzed the activity of microbial consortia relevant in Nr emissions during desiccation using transcriptome and proteome profiling and fluorescence in situ hybridization. We observed that < 30 min after wetting, genes encoding for all relevant nitrogen (N) cycling processes were expressed. The most abundant transcriptionally active N-transforming microorganisms in the investigated biocrusts were affiliated with Rhodobacteraceae, Enterobacteriaceae, and Pseudomonadaceae within the Alpha- and Gammaproteobacteria. Upon desiccation, the nitrite (NO2-) content of the biocrusts increased significantly, which was not the case when microbial activity was inhibited. Our results confirm that NO2- is the key precursor for biocrust emissions of HONO and NO. This NO2- accumulation likely involves two processes related to the transition from oxygen-limited to oxic conditions in the course of desiccation: (i) a differential regulation of the expression of denitrification genes; and (ii) a physiological response of ammonia-oxidizing organisms to changing oxygen conditions. Thus, our findings suggest that the activity of N-cycling microorganisms determines the process rates and overall quantity of Nr emissions.
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4
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Marcos MS, González MC, Vallejos MB, Barrionuevo CG, Olivera NL. Impact of irrigation with fish-processing effluents on nitrification and ammonia-oxidizer abundances in Patagonian arid soils. Arch Microbiol 2021; 203:3945-3953. [PMID: 34021768 DOI: 10.1007/s00203-021-02358-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/19/2021] [Accepted: 05/03/2021] [Indexed: 11/24/2022]
Abstract
This study aimed to evaluate the short-term effects of irrigation with diluted fish-processing effluents on soil pH, electrical conductivity, nitrification rate and abundance of ammonia oxidizers. To accomplish that, we constructed microcosms of soil from an undisturbed arid ecosystem of Patagonia, and irrigated them for 2 months with diluted effluents from a fish-processing factory or with water as control. In the initial soil sample, and along the experiment, we determined soil pH, electrical conductivity, and the concentration of inorganic nitrogen forms, which we used to calculate the net nitrification rate. We further estimated the abundances of ammonia-oxidizing archaea and bacteria in the initial soil sample and at the end of the experiment, by qPCR of amoA genes. Soil pH decreased and electrical conductivity increased in both irrigation treatments, although the effect was higher in effluent-irrigated microcosms. Soil nitrate + nitrite concentration, and thus the nitrification rate, was higher in effluent than in water-irrigated microcosms. The abundance of archaeal amoA genes was higher under effluent than water-irrigation, but that of bacterial amoA genes did not vary significantly between treatments. Neither ammonia-oxidizing archaea nor bacteria were influenced by the changes in soil pH and electrical conductivity induced by effluent irrigation.
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Affiliation(s)
- Magalí S Marcos
- Laboratorio de Microbiología y Biotecnología, Instituto Patagónico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET, CCT CONICET-CENPAT), Boulevard Brown 2915, U9120ACD, Puerto Madryn, Argentina.
| | - M Candela González
- Universidad Nacional de la Patagonia San Juan Bosco (UNPSJB), Puerto Madryn, Argentina
| | - M Belén Vallejos
- Laboratorio de Microbiología y Biotecnología, Instituto Patagónico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET, CCT CONICET-CENPAT), Boulevard Brown 2915, U9120ACD, Puerto Madryn, Argentina
| | - Cristian G Barrionuevo
- Laboratorio de Microbiología y Biotecnología, Instituto Patagónico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET, CCT CONICET-CENPAT), Boulevard Brown 2915, U9120ACD, Puerto Madryn, Argentina
| | - Nelda L Olivera
- Laboratorio de Microbiología y Biotecnología, Instituto Patagónico para el Estudio de los Ecosistemas Continentales (IPEEC-CONICET, CCT CONICET-CENPAT), Boulevard Brown 2915, U9120ACD, Puerto Madryn, Argentina
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5
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Relationships between nitrogen cycling microbial community abundance and composition reveal the indirect effect of soil pH on oak decline. THE ISME JOURNAL 2021; 15:623-635. [PMID: 33067585 PMCID: PMC8027100 DOI: 10.1038/s41396-020-00801-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 09/11/2020] [Accepted: 09/30/2020] [Indexed: 01/30/2023]
Abstract
Tree decline is a global concern and the primary cause is often unknown. Complex interactions between fluctuations in nitrogen (N) and acidifying compounds have been proposed as factors causing nutrient imbalances and decreasing stress tolerance of oak trees. Microorganisms are crucial in regulating soil N available to plants, yet little is known about the relationships between soil N-cycling and tree health. Here, we combined high-throughput sequencing and qPCR analysis of key nitrification and denitrification genes with soil chemical analyses to characterise ammonia-oxidising bacteria (AOB), archaea (AOA) and denitrifying communities in soils associated with symptomatic (declining) and asymptomatic (apparently healthy) oak trees (Quercus robur and Q. petraea) in the United Kingdom. Asymptomatic trees were associated with a higher abundance of AOB that is driven positively by soil pH. No relationship was found between AOA abundance and tree health. However, AOA abundance was driven by lower concentrations of NH4+, further supporting the idea of AOA favouring lower soil NH4+ concentrations. Denitrifier abundance was influenced primarily by soil C:N ratio, and correlations with AOB regardless of tree health. These findings indicate that amelioration of soil acidification by balancing C:N may affect AOB abundance driving N transformations, reducing stress on declining oak trees.
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Arid Ecosystem Vegetation Canopy-Gap Dichotomy: Influence on Soil Microbial Composition and Nutrient Cycling Functional Potential. Appl Environ Microbiol 2021; 87:AEM.02780-20. [PMID: 33310716 PMCID: PMC8090872 DOI: 10.1128/aem.02780-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Increasing temperatures and drought in desert ecosystems are predicted to cause decreased vegetation density combined with barren ground expansion. It remains unclear how nutrient availability, microbial diversity, and the associated functional capacity vary between vegetated-canopy and gap soils. The specific aim of this study was to characterize canopy vs gap microsite effect on soil microbial diversity, the capacity of gap soils to serve as a canopy-soil microbial reservoir, nitrogen (N)-mineralization genetic potential (ureC gene abundance) and urease enzyme activity, and microbial-nutrient pool associations in four arid-hyperarid geolocations of the western Sonoran Desert, Arizona (USA). Microsite combined with geolocation explained 57% and 45.8% of the observed variation in bacterial/archaeal and fungal community composition, respectively. A core microbiome of amplicon sequence variants was shared between the canopy and gap soil communities; however, canopy-soils included abundant taxa that were not present in associated gap communities, thereby suggesting that these taxa cannot be sourced from the associated gap soils. Linear mixed-effects models showed that canopy-soils have significantly higher microbial richness, nutrient content, and organic N-mineralization genetic and functional capacity. Furthermore, ureC gene abundance was detected in all samples suggesting that ureC is a relevant indicator of N-mineralization in deserts. Additionally, novel phylogenetic associations were observed for ureC with the majority belonging to Actinobacteria and uncharacterized bacteria. Thus, key N-mineralization functional capacity is associated with a dominant desert phylum. Overall, these results suggest that lower microbial diversity and functional capacity in gap soils may impact ecosystem sustainability as aridity drives open-space expansion in deserts.
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7
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Wang H, Cai Y, Yang Q, Gong Y, Lv G. Factors that alter the relative importance of abiotic and biotic drivers on the fertile island in a desert-oasis ecotone. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 697:134096. [PMID: 31476494 DOI: 10.1016/j.scitotenv.2019.134096] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 06/10/2023]
Abstract
Dryland vegetation forms a "fertile island effect" due to water and nutrient retention. However, there has been little research on the mechanism underlying C-, N-, P-accumulation and overall fertile island at the community level. We therefore presented the systematic investigation on this issue through the survey in desert-oasis ecotone. The survey covering the vegetation composition, plant height, crown area and vegetation cover. The main parameters measured included soil moisture, soil pH, soil salinity and nine soil indicators related to C, N and P cycling. The results revealed that the effect of fertile island was directly relevant to either soil moisture or pH. This effect was more obvious with the increase of soil moisture and the decrease of pH value. In addition, the plant diversity was believed to be the main biotic driven factor for fertile island. Furthermore, the results also indicated that both the soil moisture and plant diversity would accelerate the accumulation of P and N, while the pH played the negative effect. The other main observation obtained was that the vegetation cover had positive effect on accumulation of C. As a result, the mechanisms related to drought and salinization could drive the difference of C-, N- and P-accumulation. The main findings also provided an effective reference to better understand the mechanism of fertile island and its desertification procedure in desert-oasis ecotone.
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Affiliation(s)
- Hengfang Wang
- College of Resources and Environment Science, Xinjiang University, Urumqi 830046, China
| | - Yan Cai
- College of Resources and Environment Science, Xinjiang University, Urumqi 830046, China
| | - Qi Yang
- College of Resources and Environment Science, Xinjiang University, Urumqi 830046, China
| | - Yanming Gong
- Chinese Academy of Sciences Key Laboratory of Biogeography and Bioresources in Arid Land, Xinjiang Institute of Ecology and Geography, Urumqi 830047, China
| | - Guanghui Lv
- College of Resources and Environment Science, Xinjiang University, Urumqi 830046, China.
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8
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Trivedi C, Reich PB, Maestre FT, Hu HW, Singh BK, Delgado-Baquerizo M. Plant-driven niche differentiation of ammonia-oxidizing bacteria and archaea in global drylands. THE ISME JOURNAL 2019; 13:2727-2736. [PMID: 31249390 PMCID: PMC6794256 DOI: 10.1038/s41396-019-0465-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 06/04/2019] [Accepted: 06/07/2019] [Indexed: 12/19/2022]
Abstract
Under controlled laboratory conditions, high and low ammonium availability are known to favor soil ammonia-oxidizing bacteria (AOB) and archaea (AOA) communities, respectively. However, whether this niche segregation is maintained under field conditions in terrestrial ecosystems remains unresolved, particularly at the global scale. We hypothesized that perennial vegetation might favor AOB vs. AOA communities compared with adjacent open areas devoid of perennial vegetation (i.e., bare soil) via several mechanisms, including increasing the amount of ammonium in soil. To test this niche-differentiation hypothesis, we conducted a global field survey including 80 drylands from 6 continents. Data supported our hypothesis, as soils collected under plant canopies had higher levels of ammonium, as well as higher richness (number of terminal restriction fragments; T-RFs) and abundance (qPCR amoA genes) of AOB, and lower richness and abundance of AOA, than those collected in open areas located between plant canopies. Some of the reported associations between plant canopies and AOA and AOB communities can be a consequence of the higher organic matter and available N contents found under plant canopies. Other aspects of soils associated with vegetation including shading and microclimatic conditions might also help explain our results. Our findings provide strong evidence for niche differentiation between AOA and AOB communities in drylands worldwide, advancing our understanding of their ecology and biogeography at the global scale.
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Affiliation(s)
- Chanda Trivedi
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith South, NSW, 2751, Australia
| | - Peter B Reich
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith South, NSW, 2751, Australia
- Department of Forest Resources, University of Minnesota, St Paul, MN, 55108, USA
| | - Fernando T Maestre
- Departamento de Biología y Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, Móstoles, 28933, Spain
- Departamento de Ecología and Instituto Multidisciplinar para el Estudio del Medio "Ramon Margalef", Universidad de Alicante, Alicante, Spain
| | - Hang-Wei Hu
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Melbourne, VIC, 3010, Australia
| | - Brajesh K Singh
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith South, NSW, 2751, Australia.
- Global Centre for Land Based Innovation, Western Sydney University, Building L9, Locked Bag 1797, Penrith South, NSW, 2751, Australia.
| | - Manuel Delgado-Baquerizo
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith South, NSW, 2751, Australia.
- Departamento de Biología y Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, Móstoles, 28933, Spain.
- Cooperative Institute for Research in Environmental Science, University of Colorado Boulder, Boulder, CO, USA.
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Delgado-Baquerizo M, Fry EL, Eldridge DJ, de Vries FT, Manning P, Hamonts K, Kattge J, Boenisch G, Singh BK, Bardgett RD. Plant attributes explain the distribution of soil microbial communities in two contrasting regions of the globe. THE NEW PHYTOLOGIST 2018; 219:574-587. [PMID: 29672854 DOI: 10.1111/nph.15161] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 03/14/2018] [Indexed: 06/08/2023]
Abstract
We lack strong empirical evidence for links between plant attributes (plant community attributes and functional traits) and the distribution of soil microbial communities at large spatial scales. Using datasets from two contrasting regions and ecosystem types in Australia and England, we report that aboveground plant community attributes, such as diversity (species richness) and cover, and functional traits can predict a unique portion of the variation in the diversity (number of phylotypes) and community composition of soil bacteria and fungi that cannot be explained by soil abiotic properties and climate. We further identify the relative importance and evaluate the potential direct and indirect effects of climate, soil properties and plant attributes in regulating the diversity and community composition of soil microbial communities. Finally, we deliver a list of examples of common taxa from Australia and England that are strongly related to specific plant traits, such as specific leaf area index, leaf nitrogen and nitrogen fixation. Together, our work provides new evidence that plant attributes, especially plant functional traits, can predict the distribution of soil microbial communities at the regional scale and across two hemispheres.
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Affiliation(s)
- Manuel Delgado-Baquerizo
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, 80309, USA
- Departamento de Biología, Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, c/Tulipán s/n, 28933, Móstoles, Spain
| | - Ellen L Fry
- School of Earth and Environmental Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - David J Eldridge
- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Franciska T de Vries
- School of Earth and Environmental Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Peter Manning
- Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, Frankfurt, Germany
| | - Kelly Hamonts
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
| | - Jens Kattge
- Max Planck Institute for Biogeochemistry, PO Box 10 01 64, Jena, 07701, Germany
| | - Gerhard Boenisch
- Max Planck Institute for Biogeochemistry, PO Box 10 01 64, Jena, 07701, Germany
| | - Brajesh K Singh
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, 2751, Australia
- Global Centre for Land-Based Innovation, Western Sydney University, Penrith South DC, NSW, 2751, Australia
| | - Richard D Bardgett
- School of Earth and Environmental Sciences, The University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
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10
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Durán J, Delgado-Baquerizo M, Dougill AJ, Guuroh RT, Linstädter A, Thomas AD, Maestre FT. Temperature and aridity regulate spatial variability of soil multifunctionality in drylands across the globe. Ecology 2018; 99:1184-1193. [PMID: 29484631 PMCID: PMC6053039 DOI: 10.1002/ecy.2199] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/16/2018] [Accepted: 01/30/2018] [Indexed: 11/11/2022]
Abstract
The relationship between the spatial variability of soil multifunctionality (i.e., the capacity of soils to conduct multiple functions; SVM) and major climatic drivers, such as temperature and aridity, has never been assessed globally in terrestrial ecosystems. We surveyed 236 dryland ecosystems from six continents to evaluate the relative importance of aridity and mean annual temperature, and of other abiotic (e.g., texture) and biotic (e.g., plant cover) variables as drivers of SVM, calculated as the averaged coefficient of variation for multiple soil variables linked to nutrient stocks and cycling. We found that increases in temperature and aridity were globally correlated to increases in SVM. Some of these climatic effects on SVM were direct, but others were indirectly driven through reductions in the number of vegetation patches and increases in soil sand content. The predictive capacity of our structural equation modelling was clearly higher for the spatial variability of N- than for C- and P-related soil variables. In the case of N cycling, the effects of temperature and aridity were both direct and indirect via changes in soil properties. For C and P, the effect of climate was mainly indirect via changes in plant attributes. These results suggest that future changes in climate may decouple the spatial availability of these elements for plants and microbes in dryland soils. Our findings significantly advance our understanding of the patterns and mechanisms driving SVM in drylands across the globe, which is critical for predicting changes in ecosystem functioning in response to climate change.
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Affiliation(s)
- Jorge Durán
- Centre for Functional Ecology, University of Coimbra, 3000-456 Coimbra, Portugal
| | - Manuel Delgado-Baquerizo
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA
- Departamento de Biología y Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, 28933 Móstoles, Spain
| | - Andrew J. Dougill
- School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK
| | - Reginald T. Guuroh
- CSIR-Forestry Research Institute of Ghana, P.O. Box UP 63, KNUST, Kumasi, Ghana
- University of Cologne, Range Ecology and Range Management Group, Botanical Institute, Zuelpicher Str. 47b, 50674 Cologne, Germany
| | - Anja Linstädter
- University of Cologne, Range Ecology and Range Management Group, Botanical Institute, Zuelpicher Str. 47b, 50674 Cologne, Germany
- University of Bonn, Center for Development Research, Walter-Flex-Str. 3, 53113 Bonn, Germany
| | - Andrew D. Thomas
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, SY23 3DB, UK
| | - Fernando T. Maestre
- Departamento de Biología y Geología, Física y Química Inorgánica, Escuela Superior de Ciencias Experimentales y Tecnología, Universidad Rey Juan Carlos, 28933 Móstoles, Spain
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11
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Zhang H, Lv J, Jia Z. Detection of Ammonia-Oxidizing Bacteria (AOB) Using a Porous Silicon Optical Biosensor Based on a Multilayered Double Bragg Mirror Structure. SENSORS 2018; 18:s18010105. [PMID: 29301268 PMCID: PMC5795878 DOI: 10.3390/s18010105] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 12/23/2017] [Accepted: 12/28/2017] [Indexed: 11/28/2022]
Abstract
We successfully demonstrate a porous silicon (PS) double Bragg mirror by electrochemical etching at room temperature as a deoxyribonucleic acid (DNA) label-free biosensor for detecting ammonia-oxidizing bacteria (AOB). Compared to various other one-dimension photonic crystal configurations of PS, the double Bragg mirror structure is quite easy to prepare and exhibits interesting optical properties. The width of high reflectivity stop band of the PS double Bragg mirror is about 761 nm with a sharp and deep resonance peak at 1328 nm in the reflectance spectrum, which gives a high sensitivity and distinguishability for sensing performance. The detection sensitivity of such a double Bragg mirror structure is illustrated through the investigation of AOB DNA hybridization in the PS pores. The redshifts of the reflectance spectra show a good linear relationship with both complete complementary and partial complementary DNA. The lowest detection limit for complete complementary DNA is 27.1 nM and the detection limit of the biosensor for partial complementary DNA is 35.0 nM, which provides the feasibility and effectiveness for the detection of AOB in a real environment. The PS double Bragg mirror structure is attractive for widespread biosensing applications and provides great potential for the development of optical applications.
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Affiliation(s)
- Hongyan Zhang
- School of Physical Science and Technology, Xinjiang University, Urumqi 830046, China.
| | - Jie Lv
- College of Resource and Environment Science, Xinjiang University, Urumqi 830046, China.
| | - Zhenhong Jia
- College of Information Science and Engineering, Xinjiang University, Urumqi 830046, China.
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12
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Hu HW, Trivedi P, He JZ, Singh BK. Microbial nitrous oxide emissions in dryland ecosystems: mechanisms, microbiome and mitigation. Environ Microbiol 2017; 19:4808-4828. [DOI: 10.1111/1462-2920.13795] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/01/2017] [Accepted: 05/05/2017] [Indexed: 01/21/2023]
Affiliation(s)
- Hang-Wei Hu
- Faculty of Veterinary and Agricultural Sciences; the University of Melbourne, Parkville; Victoria 3010, Australia
| | - Pankaj Trivedi
- Department of Bioagricultural Sciences and Pest Management; Colorado State University; Fort Collins CO USA
| | - Ji-Zheng He
- Faculty of Veterinary and Agricultural Sciences; the University of Melbourne, Parkville; Victoria 3010, Australia
| | - Brajesh K. Singh
- Hawkesbury Institute for the Environment; Western Sydney University; Penrith South DC NSW 2751, Australia
- Global Centre for Land-Based Innovation; Western Sydney University; Penrith South DC NSW 2751, Australia
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Eldridge DJ, Delgado-Baquerizo M, Travers SK, Val J, Oliver I, Hamonts K, Singh BK. Competition drives the response of soil microbial diversity to increased grazing by vertebrate herbivores. Ecology 2017; 98:1922-1931. [DOI: 10.1002/ecy.1879] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/05/2017] [Accepted: 04/19/2017] [Indexed: 11/12/2022]
Affiliation(s)
- David J. Eldridge
- Office of Environment and Heritage; c/o School of Biological, Earth and Environmental Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
- Centre for Ecosystem Science; School of Biological, Earth and Environmental Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
| | - Manuel Delgado-Baquerizo
- Hawkesbury Institute for the Environment; Western Sydney University; Penrith New South Wales 2751 Australia
| | - Samantha K. Travers
- Centre for Ecosystem Science; School of Biological, Earth and Environmental Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
| | - James Val
- Office of Environment and Heritage; P.O. Box 363 Buronga New South Wales 2739 Australia
| | - Ian Oliver
- Office of Environment and Heritage; University of New England; P.O. Box U221 Armidale New South Wales 2351 Australia
- School of Environmental and Rural Sciences; University of New England; Armidale New South Wales 2350 Australia
| | - Kelly Hamonts
- Hawkesbury Institute for the Environment; Western Sydney University; Penrith New South Wales 2751 Australia
| | - Brajesh K. Singh
- Hawkesbury Institute for the Environment; Western Sydney University; Penrith New South Wales 2751 Australia
- Global Centre for Land-Based Innovation; Western Sydney University; Penrith New South Wales 2751 Australia
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Delgado-Baquerizo M, Eldridge DJ, Maestre FT, Ochoa V, Gozalo B, Reich PB, Singh BK. Aridity Decouples C:N:P Stoichiometry Across Multiple Trophic Levels in Terrestrial Ecosystems. Ecosystems 2017. [DOI: 10.1007/s10021-017-0161-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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