The role of fungi in biogenic weathering in boreal forest soils

Abstract:

In this article we discuss the possible significance of biological processes, and of fungi in particular, in weathering of minerals. We consider biological activity to be a significant driver of mineral weathering in forest ecosystems. In these environments fungi play key roles in organic matter decomposition, uptake, transfer and cycling of organic and inorganic nutrients, biogenic mineral formation, as well as transformation and accumulation of metals. The ability of lichens, mutualistic symbioses between fungi and photobionts such as algae or cyanobacteria, to weather minerals is well documented. The role of mycorrhizal fungi forming symbioses with forest trees is less well understood, but the mineral horizons of boreal forests are intensively colonised by mycorrhizal mycelia which transfer protons and organic metabolites derived from plant photosynthates to mineral surfaces, resulting in mineral dissolution and mobilisation and redistribution of anionic nutrients and metal cations. The mycorrhizal mycelia, in turn provide efficient systems for the uptake and direct transport of mobilised essential nutrients to their host plants which are large sinks. Since almost all (99.99 %) non-suberised lateral plant roots involved in nutrient uptake are covered by ectomycorrhizal fungi, most of this exchange of metabolites must take place through the plant—fungus interface. This idea is still consistent with a linear relationship between soil mineral surface area and weathering rate since the mycelia that emanate from the tree roots will have a larger area of contact with minerals if the mineral surface area is higher. Although empirical models based on bulk soil solution chemistry may fit field data, we argue that biological processes make an important contribution to mineral weathering and that a more detailed mechanistic understanding of these must be developed in order to predict responses to environmental changes and anthropogenic impact.

 

Finlay, R., Wallander, H., Smits, M., Holmstrom, S., Van Hees, P., Lian, B., Rosling, A. (2009). The role of fungi in biogenic weathering in boreal forest soils. Fungal Biology Reviews: 23; p101-106.

 

This opinion article discusses in detail mycorrhizal fungi in forest soils and how they influence soil biogeochemical cycling. The article is a little bit old, but it’s emphasis on fungi is what interests me the most. The climax of the article has a figure organizing both symbiotic (mycorrhizal) and saprotrophic fungi in relation to their contributions to soil weathering rate. The figure helps me fit fungus into the larger puzzle of biogeochemical cycling we’ve discussed in class.

Resource Recovery from Wastewater by Biological Technologies: Opportunities, Challenges, and Prospects

 Abstract
Limits in resource availability are driving a change in current societal production systems, changing the focus from residues treatment, such as wastewater treatment, toward resource recovery. Biotechnological processes offer an economic and versatile way to concentrate and transform resources from waste/wastewater into valuable products, which is a prerequisite for the technological development of a cradle-to-cradle bio-based economy. This review identifies emerging technologies that enable resource recovery across the wastewater treatment cycle. As such, bioenergy in the form of biohydrogen (by photo and dark fermentation processes) and biogas (during anaerobic digestion processes) have been classic targets, whereby, direct transformation of lipidic biomass into biodiesel also gained attention. This concept is similar to previous biofuel concepts, but more sustainable, as third generation biofuels and other resources can be produced from waste biomass. The production of high value biopolymers (e.g., for bioplastics manufacturing) from organic acids, hydrogen, and methane is another option for carbon recovery. The recovery of carbon and nutrients can be achieved by organic fertilizer production, or single cell protein generation (depending on the source) which may be utilized as feed, feed additives, next generation fertilizers, or even as probiotics. Additionlly, chemical oxidation-reduction and bioelectrochemical systems can recover inorganics or synthesize organic products beyond the natural microbial metabolism. Anticipating the next generation of wastewater treatment plants driven by biological recovery technologies, this review is focused on the generation and re-synthesis of energetic resources and key resources to be recycled as raw materials in a cradle-to-cradle economy concept.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5216025/
Puyol D, Batstone DJ, Hülsen T, Astals S, Peces M, Krömer JO. Resource Recovery from Wastewater by Biological Technologies: Opportunities, Challenges, and Prospects. Frontiers in Microbiology. 2016;7:2106. doi:10.3389/fmicb.2016.02106.
I thought that this paper was very cool to read because being able to recover materials from waste water in relation to microbial communities would prove to be crucial in the future.
down voteup vote (+1 rating, 1 votes)
Loading...

2nd Biogeo/wastewater paper

“Clouds are key components in Earth’s functioning. In addition of acting as obstacles to light radiations and chemical reactors, they are possible atmospheric oases for airborne microorganisms, providing water, nutrients and paths to the ground. Microbial activity was previously detected in clouds, but the microbial community that is active  in situ  remains unknown. Here, microbial communities in cloud water collected at puy de Dôme Mountain’s meteorological station (1465 m altitude, France) were fixed upon sampling and examined by high-throughput sequencing from DNA and RNA extracts, so as to identify active species among community members. Communities consisted of ~103−104  bacteria and archaea mL-1and ~102−103  eukaryote cells mL-1. They appeared extremely rich, with more than 28 000 distinct species detected in bacteria and 2 600 in eukaryotes. Proteobacteria and Bacteroidetes largely dominated in bacteria, while eukaryotes were essentially distributed among Fungi, Stramenopiles and Alveolata. Within these complex communities, the active members of cloud microbiota were identified as Alpha- (Sphingomonadales, Rhodospirillales and Rhizobiales), Beta- (Burkholderiales) and Gamma-Proteobacteria (Pseudomonadales). These groups of bacteria usually classified as epiphytic are probably the best candidates for interfering with abiotic chemical processes in clouds, and the most prone to successful aerial dispersion.”

Summary:  We have long known about the microbial presence within clouds but until recently most of our data has been a result of cell culturing which as we all know: may not be representative of the microbial community. This study via the use of 16s amplicon sequencing sought to define both the taxonomic identity and microbial activity via extracted DNA and RNA respectively. Atmospheric samples were taken periodically above France via a modified weather probes. Each sample was screened for the relative amount of industrial contaminants to serve as a comparison to the negative control. This study found that on average 11000 to 21000 distinct OTUs which is comparable to that of a typical soil sample. Prokaryotes made up the majority of the sample with low amounts of eukaryotic fungal populations also being present.  The source of this diversity has been attributed to aerosols particulate products that resulted from saphorytes. The Microbial richness of the aforementioned microbes was more pronounced in the contaminated samples. Between all the samples it was evident that the metabolic functions of these microbes were important for many hydrological mechanisms such as ice nucleation and ion mediated chemistry reactions which aid in both the formation of water droplets and the act of precipitation respectively. The microbiome of the cloud was found to be variable depending on the location and sensitive to changes in resources (such as industrial contaminants, temperature and topography) so further study should be allocated to defining, and in the far future, altering the clouds’ microbiome.

I chose this article because I honestly had never thought about the microbiome of clouds before and I think it is crazy when scientific papers just blow my mind with something I never considered before

down voteup vote (No Ratings Yet)
Loading...

Amato P, Joly M, Besaury L, Oudart A, Taib N, Moné AI, et al. (2017) Active microorganisms thrive among extremely diverse communities in cloud water. PLoS ONE 12(8): e0182869. https://doi.org/10.1371/journal.pone.0182869

Elucidating the impact of microbial community biodiversity on pharmaceutical biotransformation during wastewater treatment

Link:  https://onlinelibrary.wiley.com/doi/10.1111/1751-7915.12870/full

Citation:

Stadler, L. B., Vela, J. D., Jain, S., Dick, G. J., & Love, N. G. (2017). Elucidating the impact of microbial community biodiversity on pharmaceutical biotransformation during wastewater treatment.  Microbial Biotechnology,10(6). doi:10.1111/1751-7915.12870

Abstract:

In addition to removing organics and other nutrients, the microorganisms in wastewater treatment plants (WWTPs) biotransform many pharmaceuticals present in wastewater. The objective of this study was to examine the relationship between pharmaceutical biotransformation and biodiversity in WWTP bioreactor microbial communities and identify taxa and functional genes that were strongly associated with biotransformation. Dilution-to-extinction of an activated sludge microbial community was performed to establish cultures with a gradient of microbial biodiversity. Batch experiments were performed using the dilution cultures to determine biotransformation extents of several environmentally relevant pharmaceuticals. With this approach, because the communities were all established from the same original community, and using sequencing of the 16S rRNA and metatranscriptome, we identified candidate taxa and genes whose activity and transcript abundances associated with the extent of individual pharmaceutical biotransformation and were lost across the biodiversity gradient. Metabolic genes such as dehydrogenases, amidases and monooxygenases were significantly associated with pharmaceutical biotransformation, and five genera were identified whose activity significantly associated with pharmaceutical biotransformation. Understanding how biotransformation relates to biodiversity will inform the design of biological WWTPs for enhanced removal of chemicals that negatively impact environmental health.

Justification:

I thought this paper was relevant to what we recently discussed in class, especially with chemical and pharmaceutical contaminants becoming so prevalent in our waste water.

 

down voteup vote (+1 rating, 1 votes)
Loading...

High potential for temperate viruses to drive carbon cycling in chemoautotrophy-dominated shallow-water hydrothermal vents

https://onlinelibrary.wiley.com/doi/10.1111/1462-2920.13890/full

Citation:

Rastelli, E., Corinaldesi, C., Dell’Anno, A., Tangherlini, M., Martorelli, E., Ingrassia, M., … & Danovaro, R. (2017). High potential for temperate viruses to drive carbon cycling in chemoautotrophy’dominated shallow’water hydrothermal vents.  Environmental microbiology,  19(11), 4432-4446.

Abstract/Summary:

Viruses are the most abundant life forms in the world’s oceans and they are key drivers of biogeochemical cycles, but their impact on the microbial assemblages inhabiting hydrothermal vent ecosystems is still largely unknown. Here, we analysed the viral life strategies and virus-host interactions in the sediments of a newly discovered shallow-water hydrothermal field of the Mediterranean Sea. Our study reveals that temperate viruses, once experimentally induced to replicate, can cause large mortality of vent microbes, significantly reducing the chemoautotrophic carbon production, while enhancing the metabolism of microbial heterotrophs and the re-cycling of the organic matter. These results provide new insights on the factors controlling primary and secondary production processes in hydrothermal vents, suggesting that the inducible provirus-host interactions occurring in these systems can profoundly influence the functioning of the microbial food web and the efficiency in the energy transfer to the higher trophic levels.

 

Justification:

I thought the topic of viral influence on biogeochemical cycling sounded fun. Familiar material within the paper include a focus on carbon cycling and the use of metagenomics for analyzing bacteria.

 

down voteup vote (+5 rating, 5 votes)
Loading...

Genome-based microbial ecology of anammox granules in a full-scale wastewater treatment system

down voteup vote (No Ratings Yet)
Loading...

 

Citation:

Speth, D.R., Guerrero-Cruz, S., Dutilh, B.E. and Jetten, M.S., 2016. Genome-based microbial ecology of anammox granules in a full-scale wastewater treatment system.  Nature communications,  7, p.11172.

Abstract:

“Partial-nitritation anammox (PNA) is a novel wastewater treatment procedure for energy-efficient ammonium removal. Here we use genome-resolved metagenomics to build a genome-based ecological model of the microbial community in a full-scale PNA reactor. Sludge from the bioreactor examined here is used to seed reactors in wastewater treatment plants around the world; however, the role of most of its microbial community in ammonium removal remains unknown. Our analysis yielded 23 near-complete draft genomes that together represent the majority of the microbial community. We assign these genomes to distinct anaerobic and aerobic microbial communities. In the aerobic community, nitrifying organisms and heterotrophs predominate. In the anaerobic community, widespread potential for partial denitrification suggests a nitrite loop increases treatment efficiency. Of our genomes, 19 have no previously cultivated or sequenced close relatives and six belong to bacterial phyla without any cultivated members, including the most complete Omnitrophica (formerly OP3) genome to date.”

 

Justification:

I chose this article because I am interested in learning more about anammox and the role it plays in nitrogen cycling and wastewater treatment.

Decentralized approaches to wastewater treatment and management: Applicability in developing countries

down voteup vote (+3 rating, 3 votes)
Loading...

https://www-sciencedirect-com.proxy.library.uaf.edu/science/article/pii/S0301479708001618

Massoud, May A, et al. “Decentralized Approaches to Wastewater Treatment and Management: Applicability in Developing Countries.” Journal of Environmental Management, vol. 90, no. 1, Jan. 2009, pp. 652-659., doi:https://doi.org/10.1016/j.jenvman.2008.07.001.

Abstract
Providing reliable and affordable wastewater treatment in rural areas is a challenge in many parts of the world, particularly in developing countries. The problems and limitations of the centralized approaches for wastewater treatment are progressively surfacing. Centralized wastewater collection and treatment systems are costly to build and operate, especially in areas with low population densities and dispersed households. Developing countries lack both the funding to construct centralized facilities and the technical expertise to manage and operate them. Alternatively, the decentralized approach for wastewater treatment which employs a combination of onsite and/or cluster systems is gaining more attention. Such an approach allows for flexibility in management, and simple as well as complex technologies are available. The decentralized system is not only a long-term solution for small communities but is more reliable and cost effective. This paper presents a review of the various decentralized approaches to wastewater treatment and management. A discussion as to their applicability in developing countries, primarily in rural areas, and challenges faced is emphasized all through the paper. While there are many impediments and challenges towards wastewater management in developing countries, these can be overcome by suitable planning and policy implementation. Understanding the receiving environment is crucial for technology selection and should be accomplished by conducting a comprehensive site evaluation process. Centralized management of the decentralized wastewater treatment systems is essential to ensure they are inspected and maintained regularly. Management strategies should be site specific accounting for social, cultural, environmental and economic conditions in the target area.

 

After seeing the wastewater treament plan today I started thinking about how other cities/communities/states/countries may clean their wastwater, or what troubles they may face if they can not properly treat their wastewater. This article focuses on the pro’s and con’s of different types of wastewater treatment mechanisms in rural areas. They propose more efficient treatment methods for rural areas that may be lacking the infrastructure and resources for the type of treatment plant that we saw today.

How do environmental changes influence the biogeochemical cycling of arsenic?

down voteup vote (+1 rating, 1 votes)
Loading...
Hugues, T., et al. (2018). Influence of environmental changes on the biogeochemistry of arsenic in a soil polluted by the destruction of chemical weapons: A mesocosm study. Science of the Total Environment.  627. 216-226.

Abstract:

“Thermal destruction of chemical munitions from World War I led to the formation of a heavily contaminated residue that contains an unexpected mineral association in which a microbial As transformation has been observed. A mesocosm study was conducted to assess the impact of water saturation episodes and input of bioavailable organic matter (OM) on pollutant behavior in relation to biogeochemical parameters. Over a period of about eight (8) months, the contaminated soil was subjected to cycles of dry and wet periods corresponding to water table level variations. After the first four (4) months, fragmented litter from the nearby forest was placed on top of the soil. The mesocosm solid phase was sampled by three rounds of coring: at the beginning of the experiment, after four (4) months (before the addition of OM), and at the end of the experiment. Scanning electron microscopy coupled to energy dispersive X-ray spectroscopy observations showed that an amorphous phase, which was the primary carrier of As, Zn, and Cu, was unstable under water-saturated conditions and released a portion of the contaminants in solution. Precipitation of a lead arsenate chloride mineral, mimetite, in soils within the water saturated level caused the immobilization of As and Pb. Mimetite is a durable trap because of its large stability domain; however, this precipitation was limited by a low Pb concentration inducing that high amounts of As remained in solution. The addition of forest litter modified the quantities and qualities of soil OM. Microbial As transformation was affected by the addition of OM, which increased the concentration of both As(III)-oxidizing and As(V)-reducing microorganisms. The addition of OM negatively impacted the As(III) oxidizing rate, however As(III) oxidation was still the dominant reaction in accordance with the formation of arsenate-bearing minerals.”

I believe it is extremely important to investigate means of repairing the damage we bring about to the ecosystem, especially in the wake of wars or other destructive events. This paper looks at how we can utilize the knowledge and tools at our disposal to help reduce the total amount of contamination in soils by encouraging microbial activity.

https://www.sciencedirect.com/science/article/pii/S0048969718301955

Coupling of anammox and anaerobic methane oxidation in a membrane bioreactor

down voteup vote (+3 rating, 3 votes)
Loading...

Title:

Achieving high-level nitrogen removal in mainstream by coupling anammox with denitrifying anaerobic methane oxidation in a membrane biofilm reactor.

Citation:

Xie, G.J., Liu, T., Cai, C., Hu, S. and Yuan, Z., 2018. Achieving high-level nitrogen removal in mainstream by coupling anammox with denitrifying anaerobic methane oxidation in a membrane biofilm reactor.  Water Research,  131, pp.196-204.

Justification:

The coupling of carbon and nitrogen cycling in wastewater treatment has implications for shrinking of technologies which would make this strategy (if it is as effective in the real world as the lab) very effective for limited-space applications such as urban, island, and space exploration wastewater treatment.

(Also, I have found a paper that covers both allowed topics: biogeochem and WW treatment)

Abstract:

To achieve energy-neutral wastewater treatment, mainstream anaerobic ammonium oxidation (anammox) has attracted extensive attention in the past decade. However, the relatively high effluent nitrogen concentration (>10 mg N L-1) remains a significant barrier hindering its practical implementation. A novel technology integrating the anammox and denitrifying anaerobic methane oxidation (DAMO) reactions in a membrane biofilm reactor (MBfR) was developed in this study to enhance the mainstream anammox process. With the hydraulic retention time (HRT) progressively decreased from 12 to 4 h, the total nitrogen (TN) removal rate increased stepwise from 0.09 to 0.28 kg N m3 d1 , with an effluent TN concentration below 3.0 mg N L-1 achieved. Mass balance analysis showed that 30-60% of the nitrate produced by the anammox reaction was reduced back to nitrite by DAMO archaea, and the anammox and DAMO bacteria were jointly responsible for nitrite removal with contributions of >90% and <10%, respectively. Additionally, the established MBfR was robust and achieved consistently high effluent quality with >90% TN removal when the influent nitrite to ammonium molar ratio varied in the range of 1.171.55. Fluorescence in situ hybridization (FISH) and 16S rRNA gene sequencing indicated that anammox bacteria, DAMO bacteria and DAMO archaea jointly dominated the biofilm, and were likely the key contributors to nitrogen removal. This is the first study that a high nitrogen removal rate (>0.2 kg N m3 d1 ) and satisfactory effluent quality (~3 mg TN L-1) were achieved simultaneously by integrating anammox and DAMO reactions in mainstream wastewater treatment.

Is denitrifying anaerobic methane oxidation-centered technologies a solution for the sustainable operation of wastewater treatment Plants?

CITATION

Wang, D., Wang, Y., Liu, Y., Ngo, H. H., Lian, Y., Zhao, J., . . . Li, X. (2017, 06). Is                             denitrifying anaerobic methane oxidation-centered technologies a solution for             the sustainable operation of wastewater treatment Plants? Bioresource                           Technology, 234, 456-465. doi:10.1016/j.biortech.2017.02.059

 

ABSTRACT

With the world’s increasing energy crisis, society is growingly considered that the operation of wastewater treatment plants (WWTPs) should be shifted in sustainable paradigms with low energy input, or energy-neutral, or even energy output. There is a lack of critical thinking on whether and how new paradigms can be implemented in WWTPs based on the conventional process. The denitrifying anaerobic methane oxidation (DAMO) process, which uses methane and nitrate (or nitrite) as electron donor and acceptor, respectively, has recently been discovered. Based on critical analyses of this process, DAMO-centered technologies can be considered as a solution for sustainable operation of WWTPs. In this review, a possible strategy with DAMO-centered technologies was outlined and illustrated how this applies for the existing WWTPs energy-saving and newly designed WWTPs energy-neutral (or even energy-producing) towards sustainable operations.

 

LINK

https://doi.org/10.1016/j.biortech.2017.02.059

down voteup vote (No Ratings Yet)
Loading...