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Roncero-Ramos B, Savaglia V, Durieu B, Van de Vreken I, Richel A, Wilmotte A. Ecophysiological and genomic approaches to cyanobacterial hardening for restoration. J Phycol 2024; 60:465-482. [PMID: 38373045 DOI: 10.1111/jpy.13436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 12/15/2023] [Accepted: 12/15/2023] [Indexed: 02/20/2024]
Abstract
Cyanobacteria inhabit extreme environments, including drylands, providing multiple benefits to the ecosystem. Soil degradation in warm drylands is increasing due to land use intensification. Restoration methods adapted to the extreme stress in drylands are being developed, such as cyanobacteria inoculation to recover biocrusts. For this type of restoration method to be a success, it is crucial to optimize the survival of inoculated cyanobacteria in the field. One strategy is to harden them to be acclimated to stressful conditions after laboratory culturing. Here, we analyzed the genome and ecophysiological response to osmotic desiccation and UVR stresses of an Antarctic cyanobacterium, Stenomitos frigidus ULC029, which is closely related to other cyanobacteria from warm and cold dryland soils. Chlorophyll a concentrations showed that preculturing ULC029 under moderate osmotic stress improved its survival during an assay of desiccation plus rehydration under UVR. Additionally, its sequential exposure to these stress factors increased the production of exopolysaccharides, carotenoids, and scytonemin. Desiccation, but not osmotic stress, increased the concentrations of the osmoprotectants trehalose and sucrose. However, osmotic stress might induce the production of other osmoprotectants, for which the complete pathways were observed in the ULC029 genome. In total, 140 genes known to be involved in stress resistance were annotated. Here, we confirm that the sequential application of moderate osmotic stress and dehydration could improve cyanobacterial hardening for soil restoration by inducing several resistance mechanisms. We provide a high-quality genome of ULC029 and a description of the main resistance mechanisms (i.e., production of exopolysaccharides, osmoprotectants, chlorophyll, and carotenoids; DNA repair; and oxidative stress protection).
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Affiliation(s)
- Beatriz Roncero-Ramos
- InBios-Molecular Diversity and Ecology of Cyanobacteria, University of Liège, Liege, Belgium
- Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, Sevilla, Spain
| | - Valentina Savaglia
- InBios-Molecular Diversity and Ecology of Cyanobacteria, University of Liège, Liege, Belgium
- Laboratory of Protistology & Aquatic Ecology, Ghent University, Ghent, Belgium
| | - Benoit Durieu
- InBios-Molecular Diversity and Ecology of Cyanobacteria, University of Liège, Liege, Belgium
| | | | - Aurore Richel
- TERRA-Biomass and Green Technologies, University of Liège, Gembloux, Belgium
| | - Annick Wilmotte
- InBios-Molecular Diversity and Ecology of Cyanobacteria, University of Liège, Liege, Belgium
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Zhou J, Qi A, Wang T, Zhang S, Liu J, Lu Y. Exogenous chelating agents influence growth, physiological characteristics and cell ultrastructure of Robinia pseudoacacia seedlings under lead-cadmium stress. Tree Physiol 2024; 44:tpad120. [PMID: 37756614 DOI: 10.1093/treephys/tpad120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/16/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023]
Abstract
Heavy metal pollution of soil, especially by lead (Pb) and cadmium (Cd), is a serious problem worldwide. The application of safe chelating agents, combined with the growing of tolerant trees, constitutes an approach for phytoremediation of heavy-metal-contaminated soil. This study aimed to determine whether the two safe chelators, tetrasodium glutamate diacetate (GLDA) and citric acid (CA), could improve the phytoremediation capacity of black locust (Robinia pseudoacacia L.) in a Pb-Cd-contaminated soil and to find the key factors affecting the biomass accumulation of stressed black locust. In Pb- and Cd-stressed black locust plants, medium- and high-concentration GLDA treatment inhibited the growth, chlorophyll synthesis and maximum photochemical efficiency (Fv/Fm), promoted the absorption of Pb and Cd ions and resulted in the shrinkage of chloroplasts and starch grains when compared with those in Pb- and Cd-stressed plants that were not treated with GLDA. The effects of CA on plant growth, ion absorption, chlorophyll content, chlorophyll fluorescence and organelle size were significantly weaker than those of GLDA. The effect of both agents on Cd absorption was greater than that on Pb absorption in all treatments. The levels of chlorophyll a and plant tissue Cd and rates of starch metabolism were identified as the key factors affecting plant biomass accumulation in GLDA and CA treatments. In the future, GLDA can be combined with functional bacteria and/or growth promoters to promote the growth of Pb- and Cd-stressed plants and to further improve the soil restoration efficiency following pollution by heavy metals. Application of CA combined with the growing of black locust plants has great potential for restoring the Cd-polluted soil. These findings also provide insights into the practical use of GLDA and CA in phytoremediation by R. pseudoacacia and the tolerant mechanisms of R. pseudoacacia to Pb-Cd-contaminated soil.
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Affiliation(s)
- Jian Zhou
- School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
- Henan Province Engineering Center of Horticulture Plant Resource Utilization and Germplasm Enhancement, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
| | - Anguo Qi
- School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
- Henan Province Engineering Center of Horticulture Plant Resource Utilization and Germplasm Enhancement, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
| | - Ting Wang
- School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
| | - Songyan Zhang
- School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
| | - Jinxiu Liu
- School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
| | - Yabo Lu
- School of Horticulture and Landscape Architecture, Henan Institute of Science and Technology, No. 90 Hualan Road, Hongqi District, Xinxiang, Henan Province 453003, China
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Ibarra-Villarreal AL, Villarreal-Delgado MF, Parra-Cota FI, Yepez EA, Guzmán C, Gutierrez-Coronado MA, Valdez LC, Saint-Pierre C, Santos-Villalobos SDL. Effect of a native bacterial consortium on growth, yield, and grain quality of durum wheat ( Triticum turgidum L. subsp. durum) under different nitrogen rates in the Yaqui Valley, Mexico. Plant Signal Behav 2023; 18:2219837. [PMID: 37294039 PMCID: PMC10730153 DOI: 10.1080/15592324.2023.2219837] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/24/2023] [Indexed: 06/10/2023]
Abstract
A field experiment was carried out to quantify the effect of a native bacterial inoculant on the growth, yield, and quality of the wheat crop, under different nitrogen (N) fertilizer rates in two agricultural seasons. Wheat was sown under field conditions at the Experimental Technology Transfer Center (CETT-910), as a representative wheat crop area from the Yaqui Valley, Sonora México. The experiment was conducted using different doses of nitrogen (0, 130, and 250 kg N ha-1) and a bacterial consortium (BC) (Bacillus subtilis TSO9, B. cabrialesii subsp. tritici TSO2T, B. subtilis TSO22, B. paralicheniformis TRQ65, and Priestia megaterium TRQ8). Results showed that the agricultural season affected chlorophyll content, spike size, grains per spike, protein content, and whole meal yellowness. The highest chlorophyll and Normalized Difference Vegetation Index (NDVI) values, as well as lower canopy temperature values, were observed in treatments under the application of 130 and 250 kg N ha-1 (the conventional Nitrogen dose). Wheat quality parameters such as yellow berry, protein content, Sodium dodecyl sulfate (SDS)-Sedimentation, and whole meal yellowness were affected by the N dose. Moreover, the application of the native bacterial consortium, under 130 kg N ha-1, resulted in a higher spike length and grain number per spike, which led to a higher yield (+1.0 ton ha-1 vs. un-inoculated treatment), without compromising the quality of grains. In conclusion, the use of this bacterial consortium has the potential to significantly enhance wheat growth, yield, and quality while reducing the nitrogen fertilizer application, thereby offering a promising agro-biotechnological alternative for improving wheat production.
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Affiliation(s)
| | - María Fernanda Villarreal-Delgado
- Departamento de Ciencias Agronómicas y Veterinarias, Instituto Tecnológico de Sonora, Sonora, México
- Sartorius de México, Estado de México, México
| | - Fannie Isela Parra-Cota
- Campo Experimental Norman E. Borlaug, Centro de Investigación Regional Noroeste, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias, Sonora, México
| | - Enrico A. Yepez
- Departamento de Ciencias Agronómicas y Veterinarias, Instituto Tecnológico de Sonora, Sonora, México
| | - Carlos Guzmán
- Departamento de Genética, Escuela Técnica Superior de Ingeniería Agronómica Y de Montes, Edificio Gregor Mendel, Campus de Rabanales, Universidad de Córdoba. CeiA3, Córdoba, Spain
| | | | - Luis Carlos Valdez
- Departamento de Ciencias Agronómicas y Veterinarias, Instituto Tecnológico de Sonora, Sonora, México
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Moia IC, Pereira SB, Domizio P, De Philippis R, Adessi A. Phormidium ambiguum and Leptolyngbya ohadii Exopolysaccharides under Low Water Availability. Polymers (Basel) 2023; 15:polym15081889. [PMID: 37112036 PMCID: PMC10142279 DOI: 10.3390/polym15081889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/31/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Cyanobacteria can cope with various environmental stressors, due to the excretion of exopolysaccharides (EPS). However, little is known about how the composition of these polymers may change according to water availability. This work aimed at characterizing the EPS of Phormidium ambiguum (Oscillatoriales; Oscillatoriaceae) and Leptolyngbya ohadii (Pseudanabaenales; Leptolyngbyaceae), when grown as biocrusts and biofilms, subject to water deprivation. The following EPS fractions were quantified and characterized: soluble (loosely bound, LB) and condensed (tightly bound, TB) for biocrusts, released (RPS), and sheathed in P. ambiguum and glycocalyx (G-EPS) in L. ohadii for biofilms. For both cyanobacteria upon water deprivation, glucose was the main monosaccharide present and the amount of TB-EPS resulted was significantly higher, confirming its importance in these soil-based formations. Different profiles of monosaccharides composing the EPSs were observed, as for example the higher concentration of deoxysugars observed in biocrusts compared to biofilms, demonstrating the plasticity of the cells to modify EPS composition as a response to different stresses. For both cyanobacteria, both in biofilms and biocrusts, water deprivation induced the production of simpler carbohydrates, with an increased dominance index of the composing monosaccharides. The results obtained are useful in understanding how these very relevant cyanobacterial species are sensitively modifying the EPS secreted when subject to water deprivation and could lead to consider them as suitable inoculants in degraded soils.
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Affiliation(s)
- Isabela C Moia
- DAGRI-Department of Agriculture, Food, Environment and Forestry, University of Florence, Via Maragliano 77, 50144 Firenze, Italy
| | - Sara B Pereira
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- IBMC-Instituto de Biologia Celular e Molecular, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
| | - Paola Domizio
- DAGRI-Department of Agriculture, Food, Environment and Forestry, University of Florence, Via Maragliano 77, 50144 Firenze, Italy
| | - Roberto De Philippis
- DAGRI-Department of Agriculture, Food, Environment and Forestry, University of Florence, Via Maragliano 77, 50144 Firenze, Italy
| | - Alessandra Adessi
- DAGRI-Department of Agriculture, Food, Environment and Forestry, University of Florence, Via Maragliano 77, 50144 Firenze, Italy
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Alfonzetti M, Doleac S, Mills CH, Gallagher RV, Tetu S. Characterizing Effects of Microbial Biostimulants and Whole-Soil Inoculums for Native Plant Revegetation. Microorganisms 2022; 11:microorganisms11010055. [PMID: 36677347 PMCID: PMC9867050 DOI: 10.3390/microorganisms11010055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/19/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Soil microbes play important roles in plant health and ecosystem functioning, however, they can often be disturbed or depleted in degraded lands. During seed-based revegetation of such sites there is often very low germination and seedling establishment success, with recruitment of beneficial microbes to the rhizosphere one potential contributor to this problem. Here we investigated whether Australian native plant species may benefit from planting seed encapsulated within extruded seed pellets amended with one of two microbe-rich products: a commercial vermicast extract biostimulant or a whole-soil inoculum from a healthy reference site of native vegetation. Two manipulative glasshouse trials assessing the performance of two Australian native plant species (Acacia parramattensis and Indigofera australis) were carried out in both unmodified field-collected soil (trial 1) and in the same soil reduced in nutrients and microbes (trial 2). Seedling emergence and growth were compared between pelleted and bare-seeded controls and analyzed alongside soil nutrient concentrations and culturable microbial community assessments. The addition of microbial amendments maintained, but did not improve upon, high levels of emergence in both plant species relative to unamended pellets. In trial 1, mean time to emergence of Acacia parramattensis seedlings was slightly shorter in both amended pellet types relative to the standard pellets, and in trial 2, whole-soil inoculum pellets showed significantly improved growth metrics. This work shows that there is potential for microbial amendments to positively affect native plant emergence and growth, however exact effects are dependent on the type of amendment, the plant species, and the characteristics of the planting site soil.
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Affiliation(s)
- Matthew Alfonzetti
- School of Natural Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Sebastien Doleac
- School of Natural Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | | | - Rachael V. Gallagher
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
- Correspondence: (R.V.G.); (S.T.)
| | - Sasha Tetu
- School of Natural Sciences, Macquarie University, Sydney, NSW 2109, Australia
- Biomolecular Discovery Research Centre, Macquarie University, Sydney, NSW 2109, Australia
- ARC Centre of Excellence in Synthetic Biology, Macquarie University, Sydney, NSW 2109, Australia
- Correspondence: (R.V.G.); (S.T.)
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Wang Z, Pan X, Kuang S, Chen C, Wang X, Xu J, Li X, Li H, Zhuang Q, Zhang F, Wang X. Amelioration of Coastal Salt-Affected Soils with Biochar, Acid Modified Biochar and Wood Vinegar: Enhanced Nutrient Availability and Bacterial Community Modulation. Int J Environ Res Public Health 2022; 19:ijerph19127282. [PMID: 35742528 PMCID: PMC9223450 DOI: 10.3390/ijerph19127282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/08/2022] [Accepted: 06/12/2022] [Indexed: 02/04/2023]
Abstract
As an important part of the ecological environment, degraded coastal soils urgently require efficient and eco-friendly soil amendment. Biochar and wood vinegar have been proved to be effective soil amendments, and acid-modified biochar has great potential in ameliorating the degraded coastal saline-alkali soil. However, the effects of individual or combined application of biochar (BC), acid-modified biochar (ABC), and wood vinegar (WV) on coastal saline-alkali soil are unknown. Hence, biochar, wood vinegar, and acid-modified biochar were prepared by pyrolysis of poplar wood. The properties of biochar were characterized, and soil incubation experiments were conducted. The results showed that ABC decreased the soil alkalinity by acid-base neutralization and improved the soil fertility by increasing the nutrients (C, N, P). ABC provided a more suitable environment and changed the abundance and diversity of soil microorganisms. ABC increased the relative contents of specific families (e.g., Pseudomonadaceae and Sphingomonadaceae), which had strong ecological linkages in the C, N, and P cycles and organic matter degradation. The results indicated that WV had little effect on coastal saline-alkali soil, whereas individual and combined application of biochar (especially ABC) showed an efficient remediation effect. Our preliminary study demonstrated that the ABC could be a suitable solution for ameliorating degraded coastal saline-alkali soils.
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Affiliation(s)
- Zhangjun Wang
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
- R & D Center for Marine Instruments and Apparatuses, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266200, China
- Shandong SCICOM Shenguang Technology Co., Ltd., Qingdao 266300, China
| | - Xin Pan
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
- Correspondence: (X.P.); (S.K.); Tel.: +86-532-58628657 (X.P.); +86-532-88959332 (S.K.)
| | - Shaoping Kuang
- College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
- Correspondence: (X.P.); (S.K.); Tel.: +86-532-58628657 (X.P.); +86-532-88959332 (S.K.)
| | - Chao Chen
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
- R & D Center for Marine Instruments and Apparatuses, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266200, China
- Shandong SCICOM Shenguang Technology Co., Ltd., Qingdao 266300, China
| | - Xiufen Wang
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
- Shandong SCICOM Shenguang Technology Co., Ltd., Qingdao 266300, China
| | - Jie Xu
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
| | - Xianxin Li
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
- R & D Center for Marine Instruments and Apparatuses, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266200, China
| | - Hui Li
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
| | - Quanfeng Zhuang
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
| | - Feng Zhang
- Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266001, China; (Z.W.); (C.C.); (X.W.); (J.X.); (X.L.); (H.L.); (Q.Z.); (F.Z.)
| | - Xiao Wang
- Institute of Coastal Environmental Pollution Control, Key Laboratory of Marine Environment and Ecology, Ministry of Education, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China;
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Miralles I, Ortega R, Comeau AM. Functional and Taxonomic Effects of Organic Amendments on the Restoration of Semiarid Quarry Soils. mSystems 2021; 6:e0075221. [PMID: 34812648 DOI: 10.1128/mSystems.00752-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The application of organic amendments to mining soils has been shown to be a successful method of restoration, improving key physicochemical soil properties. However, there is a lack of a clear understanding of the soil bacterial community taxonomic and functional changes that are brought about by these treatments. We present further metagenomic sequencing (MGS) profiling of the effects of different restoration treatments applied to degraded, arid quarry soils in southern Spain which had previously been profiled only with 16S rRNA gene (16S) and physicochemical analyses. Both taxonomic and functional MGS profiles showed clear separation of organic treatment amendments from control samples, and although taxonomic differences were quite clear, functional redundancy was higher than expected and the majority of the latter signal came from the aggregation of minor (<0.1%) community differences. Significant taxonomic differences were seen with the presumably less-biased MGS-for example, the phylum Actinobacteria and the two genera Chloracidobacterium (Acidobacteria) and Paenibacillus (Firmicutes) were determined to be major players by the MGS and this was consistent with their potential functional roles. The former phylum was much less present, and the latter two genera were either minor components or not detected in the 16S data. Mapping of reads to MetaCyc/BioCyc categories showed overall slightly higher biosynthesis and degradation capabilities in all treatments versus control soils, with sewage amendments showing highest values and vegetable-based amendments being at intermediate levels, matching higher nutrient levels, respiration rates, enzyme activities, and bacterial biomass previously observed in the treated soils. IMPORTANCE The restoration of soils impacted by human activities poses specific challenges regarding the reestablishment of functional microbial communities which will further support the reintroduction of plant species. Organic fertilizers, originating from either treated sewage or vegetable wastes, have shown promise in restoration experiments; however, we still do not have a clear understanding of the functional and taxonomic changes that occur during these treatments. We used metagenomics to profile restoration treatments applied to degraded, arid quarry soils in southern Spain. We found that the assortments of individual functions and taxa within each soil could clearly identify treatments, while at the same time they demonstrated high functional redundancy. Functions grouped into higher pathways tended to match physicochemical measurements made on the same soils. In contrast, significant taxonomic differences were seen when the treatments were previously studied with a single marker gene, highlighting the advantage of metagenomic analysis for complex soil communities.
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Abstract
Fertile soils have been an essential resource for humanity for 10,000 y, but the ecological mechanisms involved in the creation and restoration of fertile soils, and especially the role of plant diversity, are poorly understood. Here we use results of a long-term, unfertilized plant biodiversity experiment to determine whether biodiversity, especially plant functional biodiversity, impacted the regeneration of fertility on a degraded sandy soil. After 23 y, plots containing 16 perennial grassland plant species had, relative to monocultures of these same species, ∼30 to 90% greater increases in soil nitrogen, potassium, calcium, magnesium, cation exchange capacity, and carbon and had ∼150 to 370% greater amounts of N, K, Ca, and Mg in plant biomass. Our results suggest that biodiversity, likely in combination with the increased plant productivity caused by higher biodiversity, led to greater soil fertility. Moreover, plots with high plant functional diversity, those containing grasses, legumes, and forbs, accumulated significantly greater N, K, Ca, and Mg in the total nutrient pool (plant biomass and soil) than did plots containing just one of these three functional groups. Plant species in these functional groups had trade-offs between their tissue N content, tissue K content, and root mass, suggesting why species from all three functional groups were essential for regenerating soil fertility. Our findings suggest that efforts to regenerate soil C stores and soil fertility may be aided by creative uses of plant diversity.
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Affiliation(s)
- George N Furey
- Ecology Evolution and Behavior, College of Biological Science, University of Minnesota, St. Paul, MN 55108;
| | - David Tilman
- Ecology Evolution and Behavior, College of Biological Science, University of Minnesota, St. Paul, MN 55108;
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117
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Wang Y, Jin Y, Han P, Hao J, Pan H, Liu J. Impact of Soil Disinfestation on Fungal and Bacterial Communities in Soil With Cucumber Cultivation. Front Microbiol 2021; 12:685111. [PMID: 34489884 PMCID: PMC8417054 DOI: 10.3389/fmicb.2021.685111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 07/16/2021] [Indexed: 11/13/2022] Open
Abstract
Soil treatment with disinfectants has been used for controlling soilborne phytopathogens. Besides suppressing specific pathogens, how these disinfectants impact soil health, especially soil microbial communities, is yet to be systemically determined. The objectives of this study were to examine the effects of three representative disinfectants, including the dazomet fumigant, fenaminosulf fungicide, and kasugamycin antibiotic on chemical properties, enzymatic activities, and microbial communities in soil for cucumber cultivation. Results showed that 14 days after soil treatment with these chemicals, residual content of dazomet and kasugamycin quickly declined in soil and were undetectable, while fenaminosulf residues were found at 0.48 ± 0.01 mg/kg. Total nitrogen and total carbon increased in soil after dazomet treatment. Urease and sucrase activities were significantly restrained after disinfectant application. The disinfectants did not significantly change the taxon of predominant bacteria and fungi but altered the relative abundance and diversity of soil microbiome, as well as microbial interspecific relationships. Moreover, cucumber cultivation enhanced the overall soil microbial diversity and enzymatic activities, which diminished the difference of soil microbiome among four treatments. The difference in soil microbial diversity among the four treatments became smaller after planting cucumber. Thus, soil microbial communities were affected by soil disinfectants and gradually recovered by cucumber application.
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Affiliation(s)
- Yan Wang
- College of Plant Science, Jilin University, Changchun, China
| | - Yujie Jin
- College of Plant Science, Jilin University, Changchun, China
| | - Ping Han
- Beijing Research Center for Agricultural Standards and Testing, Beijing Academy of Agriculture and Forestry Science, Beijing, China
| | - Jianjun Hao
- School of Food and Agriculture, The University of Maine, Orono, ME, United States
| | - Hongyu Pan
- College of Plant Science, Jilin University, Changchun, China
| | - Jinliang Liu
- College of Plant Science, Jilin University, Changchun, China
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Rascio I, Curci M, Gattullo CE, Lavecchia A, Yaghoubi Khanghahi M, Terzano R, Crecchio C. Combined Effect of Laboratory-Simulated Fire and Chromium Pollution on Microbial Communities in an Agricultural Soil. Biology (Basel) 2021; 10:587. [PMID: 34206819 DOI: 10.3390/biology10070587] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 11/26/2022]
Abstract
Simple Summary Soil quality and fertility rely on soil microorganisms which contribute to nutrient cycling and plant nutrition. Accidental or intentional fires can almost completely kill soil microbiota and cause soil sterilization. Fires can also destroy soil organic matter (OM), thus causing the release of potentially toxic elements such as Cr that can further disturb soil recolonization by surviving bacteria. The identification of species able to cope with such altered environments is highly relevant to restore soil life in degraded soils and to remediate polluted sites. In this study, we identified soil microorganisms potentially suitable to colonize fire-affected areas and tolerate high concentrations of bioavailable and toxic Cr, and which therefore could be useful for the above-mentioned purposes. Abstract Fire events in agricultural soils can modify not only soil properties but also the structure of soil microbial communities, especially in soils containing high concentrations of potentially toxic elements (PTEs). The recolonization of burned soils can in fact favor the proliferation of certain microorganisms, more adaptable to post-fire soil conditions and higher PTE availability, over others. In this study, we simulated with laboratory experiments the microbial recolonization of an agricultural soil containing high Cr concentrations after heating at 500 °C for 30 min, to mimic the burning of crop residues. Changes in soil properties and Cr speciation were assessed, as well as soil microbial structure by means of 16S rRNA gene sequencing. Both altered soil conditions and increased Cr availability, especially Cr(VI), appeared to be responsible for the reduction in species diversity in heated soils and the proliferation of Firmicutes. Indeed, already after 3 days from the heat treatment, Firmicutes increased from 14% to 60% relative abundance. In particular, Paenibacillus was the most abundant genus identified after the simulation, with an average relative abundance of 40%. These bacteria are known to be good fire-responders and Cr-tolerant. These results could be useful to identify bacterial strains to be used as bioindicators of altered environments and for the recovery of fire-impacted polluted sites.
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Ji C, Huang J, Tian Y, Liu Y, Barvor JB, Shao X, Li Z. Feasibility Study on the Application of Microbial Agent Modified Water-Jet Loom Sludge for the Restoration of Degraded Soil in Mining Areas. Int J Environ Res Public Health 2021; 18:6797. [PMID: 34202710 PMCID: PMC8296874 DOI: 10.3390/ijerph18136797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 05/16/2021] [Accepted: 06/16/2021] [Indexed: 11/29/2022]
Abstract
Open-pit mining causes soil damage and affects the health of the ecosystem. In the arid grassland mining areas, the soil is severely sanded, water-starved, and saline, thus making it difficult for plants and microorganisms to survive. Water-jet loom sludge can be used to improve the quality as it contains a lot of clay and is rich in organic matter, which provides a material basis for microorganism activity. To explore the effects of microbial agent-modified water-jet loom sludge on the restoration of degraded soil in grassland mining areas, four pot trials were set up, i.e., for untreated soil, the application of a microbial agent alone, the application of water-jet loom sludge alone, and the combined application of water-jet loom sludge and the microbial agent. The results show that (1) microbial agent-modified sludge can improve soil water-holding capacity and aggregate stability; (2) the nutrient content of the restored soil fraction increased significantly, and the pH of the original saline soil decreased from 9.06 to 7.84; (3) this method significantly increased plant biomass and microbial biomass carbon and enhanced the abundance and diversity of fungi and bacteria. The three treatments had different results in different soil properties, and the effect of the combined water-jet loom sludge and microbial agent treatment on soil remediation was significantly better than the individual application of either.
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Affiliation(s)
- Chuning Ji
- Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China; (C.J.); (Y.T.); (J.B.B.); (X.S.); (Z.L.)
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
| | - Jiu Huang
- Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China; (C.J.); (Y.T.); (J.B.B.); (X.S.); (Z.L.)
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
| | - Yu Tian
- Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China; (C.J.); (Y.T.); (J.B.B.); (X.S.); (Z.L.)
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
| | - Ying Liu
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
- School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, China
| | - Joshua Bosco Barvor
- Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China; (C.J.); (Y.T.); (J.B.B.); (X.S.); (Z.L.)
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
| | - Xintong Shao
- Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China; (C.J.); (Y.T.); (J.B.B.); (X.S.); (Z.L.)
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
| | - Zi’ao Li
- Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou 221116, China; (C.J.); (Y.T.); (J.B.B.); (X.S.); (Z.L.)
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China;
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Cerecetto V, Smalla K, Nesme J, Garaycochea S, Fresia P, Sørensen SJ, Babin D, Leoni C. Reduced tillage, cover crops and organic amendments affect soil microbiota and improve soil health in Uruguayan vegetable farming systems. FEMS Microbiol Ecol 2021; 97:6129805. [PMID: 33547893 DOI: 10.1093/femsec/fiab023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 02/04/2021] [Indexed: 12/13/2022] Open
Abstract
Conventional tillage and mineral fertilization (CTMF) jeopardize soil health in conventional vegetable production systems. Using a field experiment established in Uruguay in 2012, we aimed to compare the soil restoration potential of organic fertilization (compost and poultry manure) combined with conventional tillage and cover crop incorporated into the soil (CTOF) or with reduced tillage and the use of cover crop as mulch (RTOF). In 2017, table beet was cultivated under CTMF, CTOF and RTOF, and yields, soil aggregate composition and nutrients, as well as soil and table beet rhizosphere microbiota (here: bacteria and archaea) were evaluated. Microbiota was studied by high-throughput sequencing of 16S rRNA gene fragments amplified from total community DNA. RTOF exhibited higher soil aggregation, soil organic C, nutrient availability and microbial alpha-diversity than CTMF, and became more similar to an adjacent natural undisturbed site. The soil microbiota was strongly shaped by the fertilization source which was conveyed to the rhizosphere and resulted in differentially abundant taxa. However, 229 amplicon sequencing variants were found to form the core table beet rhizosphere microbiota shared among managements. In conclusion, our study shows that after only 5 years of implementation, RTOF improves soil health under intensive vegetable farming systems.
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Affiliation(s)
- Victoria Cerecetto
- Julius Kühn Institute (JKI)-Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany.,Instituto Nacional de Investigación Agropecuaria (INIA), Programa de Producción y Sustentabilidad Ambiental, Estación Experimental INIA Las Brujas, Ruta 48 Km 10, 90200 Rincón del Colorado, Canelones, Uruguay
| | - Kornelia Smalla
- Julius Kühn Institute (JKI)-Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany
| | - Joseph Nesme
- University of Copenhagen, Department of Biology, Section of Microbiology, Nørregade 10, 1165 Copenhagen, Denmark
| | - Silvia Garaycochea
- Instituto Nacional de Investigación Agropecuaria (INIA), Programa de Producción y Sustentabilidad Ambiental, Estación Experimental INIA Las Brujas, Ruta 48 Km 10, 90200 Rincón del Colorado, Canelones, Uruguay
| | - Pablo Fresia
- Unidad Mixta Institut Pasteur de Montevideo + Instituto Nacional de Investigación Agropecuaria INIA (UMPI), Mataojo 2020, 11400 Montevideo, Uruguay
| | - Søren Johannes Sørensen
- University of Copenhagen, Department of Biology, Section of Microbiology, Nørregade 10, 1165 Copenhagen, Denmark
| | - Doreen Babin
- Julius Kühn Institute (JKI)-Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany
| | - Carolina Leoni
- Instituto Nacional de Investigación Agropecuaria (INIA), Programa de Producción y Sustentabilidad Ambiental, Estación Experimental INIA Las Brujas, Ruta 48 Km 10, 90200 Rincón del Colorado, Canelones, Uruguay
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Nelson C, Giraldo-Silva A, Garcia-Pichel F. A Fog-Irrigated Soil Substrate System Unifies and Optimizes Cyanobacterial Biocrust Inoculum Production. Appl Environ Microbiol 2020; 86:e00624-20. [PMID: 32358005 DOI: 10.1128/AEM.00624-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 04/23/2020] [Indexed: 02/01/2023] Open
Abstract
Biological soil crusts (biocrusts) are globally important microbial communities inhabiting the top layer of soils. They provide multiple services to dryland ecosystems but are particularly vulnerable to anthropogenic disturbance from which they naturally recover only slowly. Assisted inoculation with cyanobacteria is held as a promising approach to promote biocrust regeneration. Two different methodologies have been developed for this purpose: mass cultivation of biocrust pioneer species (such as the cyanobacteria Microcoleus spp.) on cellulose supports, and polymicrobial cultivation of biocrusts in soils within greenhouse settings. Here, we aimed to test a novel method to grow cyanobacterial biocrust inoculum based on fog irrigation of soil substrates (FISS) that can be used with either culture-based or mixed-community approaches. We found that the FISS system presents clear advantages over previous inoculum production methodologies; overall, FISS eliminates the need for specialized facilities and decreases user effort. Specifically, there were increased microbial yields and simplification of design compared to those of the culture-based and mixed-community approaches, respectively. Its testing also allows us to make recommendations on underexplored aspects of biocrust restoration: (i) field inoculation levels should be equal to or greater than the biomass found in the substrate and (ii) practices regarding evaluation of cyanobacterial biomass should, under certain circumstances, include proxies additional to chlorophyll a IMPORTANCE Biocrust inoculum production for use in dryland rehabilitation is a powerful tool in combating the degradation of dryland ecosystems. However, the facilities and effort required to produce high-quality inoculum are often a barrier to effective large-scale implementation by land managers. By unifying and optimizing the two foremost methods for cyanobacterial biocrust inoculum production, our work improves on the ease and cost with which biocrust restoration technology can be translated to practical widespread implementation.
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Roy J, Reichel R, Brüggemann N, Hempel S, Rillig MC. Succession of arbuscular mycorrhizal fungi along a 52-year agricultural recultivation chronosequence. FEMS Microbiol Ecol 2017; 93:4082724. [PMID: 28922802 DOI: 10.1093/femsec/fix102] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 08/11/2017] [Indexed: 11/12/2022] Open
Abstract
Arbuscular mycorrhizal (AM) fungi provide a range of functions in natural and managed ecosystems. However, the trajectory of AM fungal diversity after land degradation is poorly known. We studied the succession of AM fungi along an agricultural recultivation chronosequence after open-cast mining near Cologne, Germany. We used high-throughput sequencing of the large-subunit ribosomal RNA genes to characterize the soil AM fungal communities of 10 agricultural fields spanning 52 years of recultivation. During three years, soils are recultivated with a legume, and then converted to agriculture to be later returned to local farmers implementing conventional agriculture. Our data reveal a quick and strong recovery of AM fungal richness after a few years of recultivation, but also a rapid decline following years of conventional agriculture. The community structure was strongly correlated to mineral nitrogen and phosphorus, richness peaking at high N:P ratio. This work represents the first molecular data documenting temporal patterns of AM fungal communities in agriculture; it shows the deleterious effect of conventional agricultural practices on AM fungal communities developing over time. Nonetheless, the highly dynamic nature of AM fungal communities suggests strategies for site-level management for which considering N:P stoichiometry is crucial.
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Affiliation(s)
- Julien Roy
- Institut für Biologie, Ökologie der Pflanzen, Freie Universität Berlin, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research, 14195 Berlin, Germany
| | - Rüdiger Reichel
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Agrosphere (IBG-3), 52425 Jülich, Germany
| | - Nicolas Brüggemann
- Forschungszentrum Jülich GmbH, Institute of Bio- and Geosciences, Agrosphere (IBG-3), 52425 Jülich, Germany
| | - Stefan Hempel
- Institut für Biologie, Ökologie der Pflanzen, Freie Universität Berlin, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research, 14195 Berlin, Germany
| | - Matthias C Rillig
- Institut für Biologie, Ökologie der Pflanzen, Freie Universität Berlin, 14195 Berlin, Germany.,Berlin-Brandenburg Institute of Advanced Biodiversity Research, 14195 Berlin, Germany
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Masse J, Prescott CE, Renaut S, Terrat Y, Grayston SJ. Plant Community and Nitrogen Deposition as Drivers of Alpha and Beta Diversities of Prokaryotes in Reconstructed Oil Sand Soils and Natural Boreal Forest Soils. Appl Environ Microbiol 2017; 83:e03319-16. [PMID: 28213542 DOI: 10.1128/AEM.03319-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/14/2017] [Indexed: 11/20/2022] Open
Abstract
The Athabasca oil sand deposit is one of the largest single oil deposits in the world. Following surface mining, companies are required to restore soil-like profiles that can support the previous land capabilities. The objective of this study was to assess whether the soil prokaryotic alpha diversity (α-diversity) and β-diversity in oil sand soils reconstructed 20 to 30 years previously and planted to one of three vegetation types (coniferous or deciduous trees and grassland) were similar to those found in natural boreal forest soils subject to wildfire disturbance. Prokaryotic α-diversity and β-diversity were assessed using massively parallel sequencing of 16S rRNA genes. The β-diversity, but not the α-diversity, differed between reconstructed and natural soils. Bacteria associated with an oligotrophic lifestyle were more abundant in natural forest soils, whereas bacteria associated with a copiotrophic lifestyle were more abundant in reconstructed soils. Ammonia-oxidizing archaea were most abundant in reconstructed soils planted with grasses. Plant species were the main factor influencing α-diversity in natural and in reconstructed soils. Nitrogen deposition, pH, and plant species were the main factors influencing the β-diversity of the prokaryotic communities in natural and reconstructed soils. The results highlight the importance of nitrogen deposition and aboveground-belowground relationships in shaping soil microbial communities in natural and reconstructed soils.IMPORTANCE Covering over 800 km2, land disturbed by the exploitation of the oil sands in Canada has to be restored. Here, we take advantage of the proximity between these reconstructed ecosystems and the boreal forest surrounding the oil sand mining area to study soil microbial community structure and processes in both natural and nonnatural environments. By identifying key characteristics shaping the structure of soil microbial communities, this study improved our understanding of how vegetation, soil characteristics and microbial communities interact and drive soil functions.
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Velasco Ayuso S, Giraldo Silva A, Nelson C, Barger NN, Garcia-Pichel F. Microbial Nursery Production of High-Quality Biological Soil Crust Biomass for Restoration of Degraded Dryland Soils. Appl Environ Microbiol 2017; 83:e02179-16. [PMID: 27864178 PMCID: PMC5244311 DOI: 10.1128/aem.02179-16] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 11/15/2016] [Indexed: 11/20/2022] Open
Abstract
Biological soil crusts (biocrusts) are slow-growing, phototroph-based microbial assemblages that develop on the topsoils of drylands. Biocrusts help maintain soil fertility and reduce erosion. Because their loss through human activities has negative ecological and environmental health consequences, biocrust restoration is of interest. Active soil inoculation with biocrust microorganisms can be an important tool in this endeavor. We present a culture-independent, two-step process to grow multispecies biocrusts in open greenhouse nursery facilities, based on the inoculation of local soils with local biocrust remnants and incubation under seminatural conditions that maintain the essence of the habitat but lessen its harshness. In each of four U.S. Southwest sites, we tested and deployed combinations of factors that maximized growth (gauged as chlorophyll a content) while minimizing microbial community shifts (assessed by 16S rRNA sequencing and bioinformatics), particularly for crust-forming cyanobacteria. Generally, doubling the frequency of natural wetting events, a 60% reduction in sunlight, and inoculation by slurry were optimal. Nutrient addition effects were site specific. In 4 months, our approach yielded crusts of high inoculum quality reared on local soil exposed to locally matched climates, acclimated to desiccation, and containing communities minimally shifted in composition from local ones. Our inoculum contained abundant crust-forming cyanobacteria and no significant numbers of allochthonous phototrophs, and it was sufficient to treat ca. 6,000 m2 of degraded dryland soils at 1 to 5% of the typical crust biomass concentration, having started from a natural crust remnant as small as 6 to 30 cm2 IMPORTANCE: Soil surface crusts can protect dryland soils from erosion, but they are often negatively impacted by human activities. Their degradation causes a loss of fertility, increased production of fugitive dust and intensity of dust storms with associated traffic problems, and provokes general public health hazards. Our results constitute an advance in the quest to actively restore biological soil covers by providing a means to obtain high-quality inoculum within a reasonable time (a few months), thereby allowing land managers to recover essential, but damaged, ecosystem services in a sustainable, self-perpetuating way as provided by biocrust communities.
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Affiliation(s)
| | - Ana Giraldo Silva
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
- Center for Fundamental and Applied Microbiomics, Biodesign Institute, Arizona State University, Tempe, Arizona, USA
| | - Corey Nelson
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
- Center for Fundamental and Applied Microbiomics, Biodesign Institute, Arizona State University, Tempe, Arizona, USA
| | - Nichole N Barger
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, USA
| | - Ferran Garcia-Pichel
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA
- Center for Fundamental and Applied Microbiomics, Biodesign Institute, Arizona State University, Tempe, Arizona, USA
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