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Barrón-Sandoval A, Martiny JBH, Pérez-Carbajal T, Bullock SH, Leija A, Hernández G, Escalante AE. Functional significance of microbial diversity in arid soils: biological soil crusts and nitrogen fixation as a model system. FEMS Microbiol Ecol 2023; 99:6998555. [PMID: 36690342 PMCID: PMC9923382 DOI: 10.1093/femsec/fiad009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 01/11/2023] [Accepted: 01/20/2023] [Indexed: 01/25/2023] Open
Abstract
Microbial communities respond to changes in environmental conditions; however, how compositional shifts affect ecosystem processes is still not well-understood and it is often assumed that different microbial communities will function equally under similar environmental conditions. We evaluated this assumption of functional redundancy using biological soil crusts (BSCs) from two arid ecosystems in Mexico with contrasting climate conditions (hot and cold deserts) following an experimental approach both in the field (reciprocal transplants) and in laboratory conditions (common garden), focusing on the community's composition and potential for nitrogen fixation. Potential of nitrogen fixation was assessed through the acetylene reduction assay. Community composition and diversity was determined with T-RFLPs of nifH gene, high throughput sequencing of 16S rRNA gene amplicons and metagenomic libraries. BSCs tended to show higher potential nitrogen fixation rates when experiencing temperatures more similar to their native environment. Moreover, changes in potential nitrogen fixation, taxonomic and functional community composition, and diversity often depended on an interactive effect of origin of the communities and the environment they experienced. We interpret our results as legacy effects that result from ecological specialization of the BSC communities to their native environment. Overall, we present evidence of nonfunctional redundancy of BSCs in terms of nitrogen fixation.
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Affiliation(s)
- Alberto Barrón-Sandoval
- Laboratorio Nacional de Ciencias de la Sostenibilidad (LANCIS), Instituto de Ecología, UNAM. Circuito Exterior s/n, junto al Jardín Botánico, Coyacán, Mexico City, 014510, Mexico,Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, CA 92627, United States
| | - Jennifer B H Martiny
- Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, CA 92627, United States
| | - Teresa Pérez-Carbajal
- Laboratorio Nacional de Ciencias de la Sostenibilidad (LANCIS), Instituto de Ecología, UNAM. Circuito Exterior s/n, junto al Jardín Botánico, Coyacán, Mexico City, 014510, Mexico
| | - Stephen H Bullock
- Department of Conservation Biology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ctra. Ensenada-Tijuana No. 3918, Ensenada, 22860 Baja CA, Mexico
| | - Alfonso Leija
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Av, Universidad 1001, 62210 Cuernavaca, Morelos, Mexico
| | - Georgina Hernández
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Av, Universidad 1001, 62210 Cuernavaca, Morelos, Mexico
| | - Ana E Escalante
- Corresponding author: Laboratorio Nacional de Ciencias de la Sostenibilidad (LANCIS), Instituto de Ecología, UNAM. Circuito Exterior s/n, junto al Jardín Botánico, Coyacán, Mexico City, 04510. Mexico. Tel: +52(55)5623-7714; E-mail:
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Bhaduri D, Sihi D, Bhowmik A, Verma BC, Munda S, Dari B. A review on effective soil health bio-indicators for ecosystem restoration and sustainability. Front Microbiol 2022; 13:938481. [PMID: 36060788 PMCID: PMC9428492 DOI: 10.3389/fmicb.2022.938481] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 06/29/2022] [Indexed: 11/30/2022] Open
Abstract
Preventing degradation, facilitating restoration, and maintaining soil health is fundamental for achieving ecosystem stability and resilience. A healthy soil ecosystem is supported by favorable components in the soil that promote biological productivity and provide ecosystem services. Bio-indicators of soil health are measurable properties that define the biotic components in soil and could potentially be used as a metric in determining soil functionality over a wide range of ecological conditions. However, it has been a challenge to determine effective bio-indicators of soil health due to its temporal and spatial resolutions at ecosystem levels. The objective of this review is to compile a set of effective bio-indicators for developing a better understanding of ecosystem restoration capabilities. It addresses a set of potential bio-indicators including microbial biomass, respiration, enzymatic activity, molecular gene markers, microbial metabolic substances, and microbial community analysis that have been responsive to a wide range of ecosystem functions in agricultural soils, mine deposited soil, heavy metal contaminated soil, desert soil, radioactive polluted soil, pesticide polluted soil, and wetland soils. The importance of ecosystem restoration in the United Nations Sustainable Development Goals was also discussed. This review identifies key management strategies that can help in ecosystem restoration and maintain ecosystem stability.
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Affiliation(s)
- Debarati Bhaduri
- ICAR-National Rice Research Institute, Cuttack, India
- *Correspondence: Debarati Bhaduri
| | - Debjani Sihi
- Department of Environmental Sciences, Emory University, Atlanta, GA, United States
| | - Arnab Bhowmik
- Department of Natural Resources and Environmental Design, North Carolina Agricultural and Technical State University, Greensboro, NC, United States
- Arnab Bhowmik
| | - Bibhash C. Verma
- Central Rainfed Upland Rice Research Station (ICAR-NRRI), Hazaribagh, India
| | | | - Biswanath Dari
- Agriculture and Natural Resources, Cooperative Extension at North Carolina Agricultural and Technical State University, Greensboro, NC, United States
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3
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Liu X, Tang Z, Zhang Q, Kong W. The contrasting effects of biochar and straw on N 2O emissions in the maize season in intensively farmed soil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:29806-29819. [PMID: 33566298 DOI: 10.1007/s11356-021-12722-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/26/2021] [Indexed: 06/12/2023]
Abstract
This study evaluated the combined effects of biochar and straw on N2O flux and the community compositions of nitrifiers and denitrifiers in the maize season in an intensively farmed area in northern China. The experiment consisted of four treatments: (1) CK (only chemical fertilizer application); (2) C (biochar application); (3) SR (straw application to the field); and (4) C+SR (the application of both biochar and straw). The results indicated that during the maize growing season, N2O flux decreased by 30.3% in the C treatment and increased by 13.2% and 37.0% in the SR and C+SR treatments compared with CK, respectively. NO3--N, NH4+-N, and microbial biomass carbon (MBC) were the main soil factors affecting N2O flux, and they were positively correlated with NO3--N and negatively correlated with MBC in the C treatment and positively correlated with NH4+-N in the SR and C+SR treatments. Both biochar addition and straw return shifted the community compositions of nitrifiers and denitrifiers. N2O production was mainly reduced by promoting the ammonia-oxidizing bacteria (AOB) gene abundance and inhibiting the nirK gene abundance in the C treatment but promoted by inhibiting the AOB and nosZ gene abundances in the SR and C+SR treatments. Nitrosospira (AOB) and Rhizobium (nirK) were the main contributors among the treatments. NO3--N, NH4+-N, and MBC were the main soil factors affecting the denitrifier communities. The predominant species associated with the nirK, nirS, and nosZ genes were positively correlated with NO3--N and MBC and negatively correlated with NH4+-N. These results provide valuable information on the mechanism of N2O production and reduction in biochar- and straw-amended soil under field conditions.
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Affiliation(s)
- Xingren Liu
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
| | - Zhanming Tang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Qingwen Zhang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Weidong Kong
- Key Laboratory of Alpine Ecology, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.
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4
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Díaz-Rodríguez AM, Salcedo Gastelum LA, Félix Pablos CM, Parra-Cota FI, Santoyo G, Puente ML, Bhattacharya D, Mukherjee J, de los Santos-Villalobos S. The Current and Future Role of Microbial Culture Collections in Food Security Worldwide. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2021. [DOI: 10.3389/fsufs.2020.614739] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Food security is the pillar of nutritional wellbeing for food availability, and is necessary to satisfy all physiological needs to thus maintain the general wellbeing of populations. However, global agricultural deficiencies occur due to rapid population growth, causing an increase in competition for resources; such as water, land, and energy, leading to the overexploitation of agro-ecosystems, and the inability to produce a suitable quantity of efficient food. Therefore, the development of sustainable agro-biotechnologies is vital to increase crop yield and quality, reducing the negative impacts caused by intensive non-sustainable agricultural practices. In this way, the genetic and metabolic diversity of soil and plant microbiota in agro-ecosystems are a current and promising alternative to ensure global food security. Microbial communities play an important role in the improvement of soil fertility and plant development by enhancing plant growth and health through several direct and/or indirect mechanisms. Thus, the bio-augmentation of beneficial microbes into agro-ecosystems not only generates an increase in food production but also mitigates the economic, social, and environmental issues of intensive non-sustainable agriculture. In this way, the isolation, characterization, and exploitation of preserved beneficial microbes in microbial culture collections (MCC) is crucial for the ex situ maintenance of native soil microbial ecology focused on driving sustainable food production. This review aims to provide a critical analysis of the current and future role of global MCC on sustainable food security, as providers of a large number of beneficial microbial strains with multiple metabolic and genetic traits.
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Moreira CC, Celestino D, Guerra Sobrinho T, Cardoso IM, Elliot SL. Agroforestry coffee soils increase the insect-suppressive potential offered by entomopathogenic fungi over full-sun soils: A case proposing a "bait survival technique". Ecol Evol 2019; 9:10777-10787. [PMID: 31624581 PMCID: PMC6787780 DOI: 10.1002/ece3.5598] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 07/11/2019] [Accepted: 07/16/2019] [Indexed: 01/28/2023] Open
Abstract
Entomopathogenic fungi are important natural enemies of insects. However, there is little information on the insect-suppressive potential of these fungi and possible effects of farming management on this. Meanwhile, changes in natural landscapes due to agricultural intensification have caused considerable biodiversity loss and consequent decay of ecosystem services. However, the adoption of practices such as agroforestry in agroecosystems can foster abiotic and biotic conditions that conserve biodiversity, consequently restoring the provision of ecosystems services. Here, we assessed the effect of management systems (agroforestry or full-sun) on the pest-suppressive potential of entomopathogenic fungi in Brazilian coffee plantations. We used the insect bait method coupled with survival analyses to assess the speed of kill by entomopathogenic fungi and their presence in soil samples from both farming systems. We found that insects exposed to agroforestry soils died more quickly than insects exposed to full-sun soils. Of the fungi isolated from the bait insects, Metarhizium was found most frequently, followed by Beauveria. Meanwhile, Fusarium was frequently isolated as primary or secondary infections. We propose that the differential survival of insects is indicative of a greater suppressive potential by entomopathogenic fungi in agroforestry, and that this could be promoted by the diversified landscape, microclimatic stability, and reduced soil disturbance in agroforestry systems. Furthermore, our results provide a useful demonstration of the potential use of the insect bait method to investigate pest-suppressive potential through bait insect mortality, and we term this the "bait survival technique."
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Affiliation(s)
| | - Daiane Celestino
- Departamento de EntomologiaUniversidade Federal de ViçosaViçosaMGBrazil
| | - Tathiana Guerra Sobrinho
- Departamento de Biologia Geral, EcologiaUniversidade Federal de ViçosaViçosaMGBrazil
- Departamento de Ciências Agrárias e BiológicasUniversidade Federal do Espírito SantoSão MateusESBrazil
| | | | - Simon Luke Elliot
- Departamento de EntomologiaUniversidade Federal de ViçosaViçosaMGBrazil
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Rebollar EA, Sandoval-Castellanos E, Roessler K, Gaut BS, Alcaraz LD, Benítez M, Escalante AE. Seasonal Changes in a Maize-Based Polyculture of Central Mexico Reshape the Co-occurrence Networks of Soil Bacterial Communities. Front Microbiol 2017; 8:2478. [PMID: 29326663 PMCID: PMC5741676 DOI: 10.3389/fmicb.2017.02478] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/29/2017] [Indexed: 11/26/2022] Open
Abstract
The milpa is a traditional maize-based polyculture in Mexico that is typically practiced as rainfed agriculture. Because milpa cultivation has been practiced over a vast range of environmental and cultural conditions, this agroecosystem is recognized as an important repository of biological and cultural diversity. As for any agroecosystem, the relationship between plant development and the biogeochemical processes of the soil is critical. Although the milpa has been studied from different perspectives, the diversity and structure of microbial communities within milpa soils remain largely unexplored. In this study, we surveyed a milpa system in Central Mexico across cropping season: before planting (dry season; t1), during the early growth of plants (onset of the rainy season; t2), and before harvest (end of the rainy season; t3). In order to examine changes in community structure through time, we characterized bacterial diversity through high-throughput sequencing of 16S rRNA gene amplicons and recorded the nutrient status of multiple (5–10) soil samples from our milpa plots. We estimated microbial diversity from a total of 90 samples and constructed co-occurrence networks. Although we did not find significant changes in diversity or composition of bacterial communities across time, we identified significant rearrangements in their co-occurrence network structure. We found particularly drastic changes between the first and second time points. Co-occurrence analyses showed that the bacterial community changed from a less structured network at (t1) into modules with a non-random composition of taxonomic groups at (t2). We conclude that changes in bacterial communities undetected by standard diversity analyses can become evident when performing co-occurrence network analyses. We also postulate possible functional associations among keystone groups suggested by biogeochemical processes. This study represents the first contribution on soil microbial diversity of a maize-based polyculture and shows its dynamic nature in short-term scales.
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Affiliation(s)
- Eria A Rebollar
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | | - Kyria Roessler
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States
| | - Brandon S Gaut
- Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States
| | - Luis D Alcaraz
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mariana Benítez
- Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico.,Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Ana E Escalante
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Mexico City, Mexico
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7
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Ishaq SL, Johnson SP, Miller ZJ, Lehnhoff EA, Olivo S, Yeoman CJ, Menalled FD. Impact of Cropping Systems, Soil Inoculum, and Plant Species Identity on Soil Bacterial Community Structure. MICROBIAL ECOLOGY 2017; 73:417-434. [PMID: 27677892 DOI: 10.1007/s00248-016-0861-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/13/2016] [Indexed: 06/06/2023]
Abstract
Farming practices affect the soil microbial community, which in turn impacts crop growth and crop-weed interactions. This study assessed the modification of soil bacterial community structure by organic or conventional cropping systems, weed species identity [Amaranthus retroflexus L. (redroot pigweed) or Avena fatua L. (wild oat)], and living or sterilized inoculum. Soil from eight paired USDA-certified organic and conventional farms in north-central Montana was used as living or autoclave-sterilized inoculant into steam-pasteurized potting soil, planted with Am. retroflexus or Av. fatua and grown for two consecutive 8-week periods to condition soil nutrients and biota. Subsequently, the V3-V4 regions of the microbial 16S rRNA gene were sequenced by Illumina MiSeq. Treatments clustered significantly, with living or sterilized inoculum being the strongest delineating factor, followed by organic or conventional cropping system, then individual farm. Living inoculum-treated soil had greater species richness and was more diverse than sterile inoculum-treated soil (observed OTUs, Chao, inverse Simpson, Shannon, P < 0.001) and had more discriminant taxa delineating groups (linear discriminant analysis). Living inoculum soil contained more Chloroflexi and Acidobacteria, while the sterile inoculum soil had more Bacteroidetes, Firmicutes, Gemmatimonadetes, and Verrucomicrobia. Organically farmed inoculum-treated soil had greater species richness, more diversity (observed OTUs, Chao, Shannon, P < 0.05), and more discriminant taxa than conventionally farmed inoculum-treated soil. Cyanobacteria were higher in pots growing Am. retroflexus, regardless of inoculum type, for three of the four organic farms. Results highlight the potential of cropping systems and species identity to modify soil bacterial communities, subsequently modifying plant growth and crop-weed competition.
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Affiliation(s)
- Suzanne L Ishaq
- Department of Animal and Range Sciences, Montana State University, P.O. Box 172900, Bozeman, MT, 59717, USA
- Department of Land Resources and Environmental Sciences, Montana State University, P.O. Box 173120, Bozeman, MT, 59717, USA
| | - Stephen P Johnson
- Department of Land Resources and Environmental Sciences, Montana State University, P.O. Box 173120, Bozeman, MT, 59717, USA
| | - Zach J Miller
- Western Agriculture Research Center, Montana State University, Bozeman, MT, USA
| | - Erik A Lehnhoff
- Department of Entomology, Plant Pathology and Weed Science, New Mexico State University, Las Cruces, NM, USA
| | - Sarah Olivo
- Department of Animal and Range Sciences, Montana State University, P.O. Box 172900, Bozeman, MT, 59717, USA
| | - Carl J Yeoman
- Department of Animal and Range Sciences, Montana State University, P.O. Box 172900, Bozeman, MT, 59717, USA.
| | - Fabian D Menalled
- Department of Land Resources and Environmental Sciences, Montana State University, P.O. Box 173120, Bozeman, MT, 59717, USA.
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Wood SA, Sokol N, Bell CW, Bradford MA, Naeem S, Wallenstein MD, Palm CA. Opposing effects of different soil organic matter fractions on crop yields. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:2072-2085. [PMID: 27755738 DOI: 10.1890/16-0024.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 02/10/2016] [Indexed: 05/15/2023]
Abstract
Soil organic matter is critical to sustainable agriculture because it provides nutrients to crops as it decomposes and increases nutrient- and water-holding capacity when built up. Fast- and slow-cycling fractions of soil organic matter can have different impacts on crop production because fast-cycling fractions rapidly release nutrients for short-term plant growth and slow-cycling fractions bind nutrients that mineralize slowly and build up water-holding capacity. We explored the controls on these fractions in a tropical agroecosystem and their relationship to crop yields. We performed physical fractionation of soil organic matter from 48 farms and plots in western Kenya. We found that fast-cycling, particulate organic matter was positively related to crop yields, but did not have a strong effect, while slower-cycling, mineral-associated organic matter was negatively related to yields. Our finding that slower-cycling organic matter was negatively related to yield points to a need to revise the view that stabilization of organic matter positively impacts food security. Our results support a new paradigm that different soil organic matter fractions are controlled by different mechanisms, potentially leading to different relationships with management outcomes, like crop yield. Effectively managing soils for sustainable agriculture requires quantifying the effects of specific organic matter fractions on these outcomes.
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Affiliation(s)
- Stephen A Wood
- Department of Ecology, Evolution & Environmental Biology, Columbia University, 1200 Amsterdam Ave., 10th Fl., New York, New York, 10027, USA.
- Agriculture and Food Security Center, The Earth Institute at Columbia University, 61 Route 9W, Lamont Hall, 2G, New York, New York, 10964, USA.
| | - Noah Sokol
- School of Forestry and Environmental Studies, Yale University, 195 Prospect St., New Haven, Connecticut, 06511, USA
| | - Colin W Bell
- Natural Resource Ecology Laboratory, Colorado State University, 1499 Campus Delivery, Fort Collins, Colorado, 80523, USA
| | - Mark A Bradford
- School of Forestry and Environmental Studies, Yale University, 195 Prospect St., New Haven, Connecticut, 06511, USA
| | - Shahid Naeem
- Department of Ecology, Evolution & Environmental Biology, Columbia University, 1200 Amsterdam Ave., 10th Fl., New York, New York, 10027, USA
| | - Matthew D Wallenstein
- Natural Resource Ecology Laboratory, Colorado State University, 1499 Campus Delivery, Fort Collins, Colorado, 80523, USA
| | - Cheryl A Palm
- Agriculture and Food Security Center, The Earth Institute at Columbia University, 61 Route 9W, Lamont Hall, 2G, New York, New York, 10964, USA
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Reverchon F, Bai SH, Liu X, Blumfield TJ. Tree Plantation Systems Influence Nitrogen Retention and the Abundance of Nitrogen Functional Genes in the Solomon Islands. Front Microbiol 2015; 6:1439. [PMID: 26733978 PMCID: PMC4686685 DOI: 10.3389/fmicb.2015.01439] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/03/2015] [Indexed: 11/13/2022] Open
Abstract
Tree mono-plantations are susceptible to soil nutrient impoverishment and mixed species plantations have been proposed as a way of maintaining soil fertility while enhancing biodiversity. In the Solomon Islands, mixed species plantations where teak (Tectona grandis) is inter-planted with a local tree species (Flueggea flexuosa) have been used as an alternative to teak mono-plantations and are expected to increase soil microbial diversity and modify microbial biogeochemical processes. In this study, we quantified the abundance of microbial functional genes involved in the nitrogen (N) cycle from soil samples collected in teak, flueggea, and mixed species plantations. Furthermore, we measured soil properties such as pH, total carbon (C) and total N, stable N isotope composition (δ(15)N), and inorganic N pools. Soil pH and δ(15)N were higher under teak than under flueggea, which indicates that intercropping teak with flueggea may decrease bacterial activities and potential N losses. Higher C:N ratios were found under mixed species plantations than those under teak, suggesting an enhancement of N immobilization that would help preventing fast N losses. However, inorganic N pools remained unaffected by plant cover. Inter-planting teak with flueggea in mixed species plantations generally increased the relative abundance of denitrification genes and promoted the enrichment of nosZ-harboring denitrifiers. However, it reduced the abundance of bacterial amoA (ammonia monooxygenase) genes compared to teak mono-plantations. The abundance of most denitrification genes correlated with soil total N and C:N ratio, while bacterial and archeal nitrification genes correlated positively with soil NH4 (+) concentrations. Altogether, these results show that the abundance of bacterial N-cycling functional guilds vary under teak and under mixed species plantations, and that inter-planting teak with flueggea may potentially alleviate N losses associated with nitrification and denitrification and favor N retention. Mixed plantations could also allow an increase in soil C and N stocks without losing the source of income that teak trees represent for local communities.
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Affiliation(s)
- Frédérique Reverchon
- Instituto de Ecología A.C., Red de Estudios Moleculares AvanzadosXalapa, México
- Environmental Futures Research Institute, School of Natural Sciences, Griffith University, NathanQLD, Australia
| | - Shahla H. Bai
- Environmental Futures Research Institute, School of Natural Sciences, Griffith University, NathanQLD, Australia
- Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, MaroochydoreQLD, Australia
| | - Xian Liu
- Environmental Futures Research Institute, School of Environment, Griffith University, NathanQLD, Australia
- Forestry College, Fujian Agriculture and Forestry UniversityFuzhou, China
| | - Timothy J. Blumfield
- Environmental Futures Research Institute, School of Natural Sciences, Griffith University, NathanQLD, Australia
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10
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Wood SA, Karp DS, DeClerck F, Kremen C, Naeem S, Palm CA. Functional traits in agriculture: agrobiodiversity and ecosystem services. Trends Ecol Evol 2015; 30:531-9. [PMID: 26190137 DOI: 10.1016/j.tree.2015.06.013] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 06/20/2015] [Accepted: 06/24/2015] [Indexed: 11/16/2022]
Abstract
Functional trait research has led to greater understanding of the impacts of biodiversity in ecosystems. Yet, functional trait approaches have not been widely applied to agroecosystems and understanding of the importance of agrobiodiversity remains limited to a few ecosystem processes and services. To improve this understanding, we argue here for a functional trait approach to agroecology that adopts recent advances in trait research for multitrophic and spatially heterogeneous ecosystems. We suggest that trait values should be measured across environmental conditions and agricultural management regimes to predict how ecosystem services vary with farm practices and environment. This knowledge should be used to develop management strategies that can be easily implemented by farmers to manage agriculture to provide multiple ecosystem services.
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Affiliation(s)
- Stephen A Wood
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY 10027, USA; Agriculture and Food Security Center, The Earth Institute, Columbia University, Palisades, NY 10964, USA.
| | - Daniel S Karp
- Department of Environmental Sciences, Policy and Management, University of California, Berkeley, Berkeley, CA 94720, USA; The Nature Conservancy, Berkeley, CA 94705, USA
| | - Fabrice DeClerck
- Agriculture and Food Security Center, The Earth Institute, Columbia University, Palisades, NY 10964, USA; Agrobiodiversity and Ecosystem Services Programme, Biodiversity International, Montpellier 34000, France
| | - Claire Kremen
- Department of Environmental Sciences, Policy and Management, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Shahid Naeem
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, NY 10027, USA
| | - Cheryl A Palm
- Agriculture and Food Security Center, The Earth Institute, Columbia University, Palisades, NY 10964, USA
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11
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Wood SA, Bradford MA, Gilbert JA, McGuire KL, Palm CA, Tully KL, Zhou J, Naeem S. Agricultural intensification and the functional capacity of soil microbes on smallholder African farms. J Appl Ecol 2015. [DOI: 10.1111/1365-2664.12416] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stephen A. Wood
- Department of Ecology, Evolution & Environmental Biology; Columbia University; New York NY 10027 USA
- Agriculture and Food Security Center; The Earth Institute; Columbia University; Palisades NY 10964 USA
| | - Mark A. Bradford
- School of Forestry and Environmental Studies; Yale University; New Haven CT 06511 USA
| | - Jack A. Gilbert
- Argonne National Laboratory; Institute for Genomic and Systems Biology; Argonne IL 60439 USA
| | - Krista L. McGuire
- Department of Ecology, Evolution & Environmental Biology; Columbia University; New York NY 10027 USA
- Department of Biology; Barnard College of Columbia University; New York NY 10027 USA
| | - Cheryl A. Palm
- Agriculture and Food Security Center; The Earth Institute; Columbia University; Palisades NY 10964 USA
| | - Katherine L. Tully
- Agriculture and Food Security Center; The Earth Institute; Columbia University; Palisades NY 10964 USA
| | - Jizhong Zhou
- Department of Microbiology and Plant Biology; Institute for Environmental Genomics; University of Oklahoma; Norman OK 73019 USA
- Earth Science Division; Lawrence Berkeley National Laboratory; Berkeley CA 94720 USA
- State Key Joint Laboratory of Environment Simulation and Pollution Control; School of Environment; Tsinghua University; Beijing 100084 China
| | - Shahid Naeem
- Department of Ecology, Evolution & Environmental Biology; Columbia University; New York NY 10027 USA
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