About
188
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Introduction
The main objective is to understand community structure in soil ecology and ecosystem succession. We use stable and radioactive isotopes, microcosms, field sampling, DNA sequence information, bioinformatics, and microscopy. I have published on modernizing eukaryote classification, systematics, and nomenclature, including work on the PhyloCode. I am currently working on global protist biogeography, global food security and development, dating the origin of eukaryotes, and 3 university textbooks.
Current institution
Additional affiliations
October 2015 - November 2015
June 2014 - August 2020
Position
- Grievance Committee
Description
- Grievance officer for a cumulative 9 years (as of 2020, with 2 years at Dalhousie University) addressing faculty relations issues with the university senior administration, on behalf of the University Faculty Association.
June 2016 - September 2016
Northeast Institute of Geography and Agroecology (IGA)
Position
- CEO
Description
- 1-3 months annually in collaborative research with various colleagues
Education
September 1985 - July 1998
Field of study
- diversity, protistology, microbial ecology, genetics and development, history and philosophy of science
Publications
Publications (188)
The diversity of life is one of the most striking aspects of our planet; hence knowing how many species inhabit Earth is among the most fundamental questions in science. Yet the answer to this question remains enigmatic, as efforts to sample the world's biodiversity to date have been limited and thus have precluded direct quantification of global s...
The soil food web is often described as having three main energy channels: root, bacterial and fungal. Here we provide quantitative data using a sensitive stable isotope ratio mass spectrometry procedure with microcosms on species interactions in the fungal pathway. We measured ¹⁵N and ¹³C enrichment in microarthropods through grazing rare isotope...
Salinity stress adversely affects root nodulation symbiotic relationships, and ultimately the nitrogen fixation capacity and the growth and yield of leguminous plants. Improving growth and biological nitrogen fixation of leguminous plants grown on salt–affected soils are considered to be a striking challenge. Most of the findings reveal that co–ino...
In most terrestrial ecosystems, nitrogen (N) is an essential and often limiting element for living organisms. There is competition for the available N between roots, rhizosphere organisms and the overall soil food web. N derived from biological fixation in the soil reaches the above ground terrestrial food web through two pathways: from root uptake...
"Genetic code" origin evolution "Tessera code" tetracodon tricodon non-standard genetic codes
protist chemotaxis behaviour parasite life cycles "optimal foraging"
Sex in protists, evolution of mating types, Muller's ratchet, benefits of sex, clonal species, selfing, autogamy, mating types in Fungi, conjugation in ciliates, out-crossing species, genome rearrangements, meiosis toolkit, neutral mutations, immortal cell lines, sexual life cycles
Acquisition of photosynthetic plastids in protists by secondary and tertiary serial endosymbiosis
evolution of photosynthesis in eukaryotes from primary endosymbiosis
protist bacteria symbionts, extrusomes, loss of mitochondrion functions, loss of photosynthesis, termite endosymbionts syntrophy
Excavates: Discoba and Metamonada were in a supergroup called Excavata, which included malawimonads. The monophyly of this clade was never certain but probable, even though the monophyly of each Discoba and Metamonada is not in question. They were separated into two basal clades to other eukaryotes in the most recent 2019 revision of the classifica...
A major tour de force was achieved by Joe Frankel in a book that synthesised decades of cell shape experimentation with Ciliophora. Developments in understanding embryology (invertebrate models) and pattern formation from both a physical chemistry and a cell biology perspective were brought together to explain the observations in Ciliophora. There...
A glossary of standard terms as used in the protistology book.
Description of groups at the base of the animals and fungi, presentation of the transition to animals and fungi, presentation of the diversity across fungi, description of the sponges, discussion of the origin of multicellularity in animals.
Description of the diversity across red algae and green algae, origin of the Archaeplastida, presentation of the transition to multicellularity in plants.
Description of the diversity of protists across the Stramenopiles.
Introduction to protists, lateral gene transfer in protist evolution, and diversity (and loss) of sexual processes across the diversity of protists.
Constructing a classification from a phylogeny is not a straightforward process. Uncertainties in the phylogeny, especially with unresolved nodes, need to be included in a classification. Codes of Nomenclature tend to link a taxon name and rank as a single name. This causes instability due to name changes when the rank changes, or the species is mo...
Crop production is strongly impacted by soil nitrogen supply, which is regulated by soil micro-food webs consisting of nematodes, protists, fungi and bacteria. However, responses of soil micro-food webs to fertilization at the aggregate scale and their relationships with soil nitrogen supply and crop yield remain unclear. To address these knowledge...
ABSTRACT
Enhancing soil organic carbon (SOC) levels via improved fertilization strategies can promote soil health and support sustainable crop production. While bacteria and fungi play a key role in SOC accumulation, the effects of soil micro-food webs that include organisms from higher trophic levels remain uncertain. We sought to narrow
this know...
The eukaryotic parasites of medical importance are classically known as protozoan, arthropod, and helminthic parasites; the last includes nematodes, cestodes, trematodes, and acanthocephalans. The modern classification of biological species intends to reflect an evolutionary history of living organisms. Eukaryotes are divided into five monophyletic...
The eukaryotic parasites of medical importance are classically known as protozoan, arthropod, and helminthic parasites; the last includes nematodes, cestodes, trematodes, and acanthocephalans. The modern classification of biological species intends to reflect an evolutionary history of living organisms. Eukaryotes are divided into five monophyletic...
Abstract
Seed priming improves seed germination, plant establishment and growth even under stressful conditions. We studied the effect of seed priming with bulk (2 lm particles) and nanoparticle (13 nm) TiO2 on physiological characteristics, essential oil content and percentage and free radical scavenging activity in marjoram (Origanum majorana L.)...
The nitrogen (N) content of soil organic matter (OM) fractions is a vital indicator of soil health as it limits crop yield and regulates the loss of N from soil to the environment. We studied the impacts of introducing leguminous green manure (LGM) to replace summer fallow on N distribution in coarse particulate OM (cPOM), fine POM (fPOM), intra-mi...
This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Abstract Ecologists have long debated the properties that confer stability to complex, species-rich ecological networks. Species-level soil food...
Flower-visiting insects have co-evolved with flowering-plants. While it has been shown that floral traits and environmental factors influence insects visitations during the day, it is yet unclear how these factors influence insects visitations at night. We sampled a montane meadow located near Jilin in northeastern China in July and August in 2019,...
Agriculture in the boreal and Arctic regions is perceived as marginal, low intensity and inadequate to satisfy the needs of local communities, but another perspective is that northern agriculture has untapped potential to increase the local supply of food and even contribute to the global food system. Policies across northern jurisdictions target t...
Understanding the factors determining the formation of each community and metacommunity across a landscape is one of the most important ideas in soil animal ecology. However, the variables and parameters that shape soil arthropod communities in agroecosystems have not been resolved. These arthropods can serve as important bioindicators of field man...
Dinophytes are widely distributed in marine‐ and fresh‐waters, but have yet to be conclusively documented in terrestrial environments. Here, we evaluated the presence of these protists from an environmental DNA metabarcoding dataset of Neotropical rainforest soils. Using a phylogenetic placement approach with a reference alignment and tree, we show...
Dinophytes are widely distributed in marine- and fresh-waters, but have yet to be conclusively documented in terrestrial environments. Here we evaluated the presence of these protists from an environmental DNA metabarcoding dataset of Neotropical rainforest soils. Using a phylogenetic placement approach with a reference alignment and tree, we showe...
Editors: Kevin de Queiroz, Philip D. Cantino, and Jacques A. Gauthier
Editorial Board: Sina M. Adl (University of Saskatchewan), Frank E. Anderson (Southern Illinois
University), Benoît Dayrat (Pennsylvania State University), Walter G. Joyce (Université de Fribourg),
Matjaž Kuntner (National Institute of Biology, Slovenia), Michel Laurin (CNRS, Fr...
One of the main obstacles to plant growth is the lack of the availability of nutrient elements in many agricultural environments in the world, especially the tropics where soils can be extremely low in nutrients. Using different mechanisms of action, plant growth-promoting rhizobacteria (PGPR) participate in geochemical nutrition cycles and determi...
Evaluating the impacts of growing leguminous green manure (LGM) on soil organic carbon (SOC) stabilization is crucial to evaluate the sustainability of this management practice. To clarify this, we measured organic carbon (OC) fractions and used protected C to estimate the stability of SOC. The field study was a split‐plot design with four main tre...
Collembola display a variety of feeding habits, and prey on many types of food at different trophic levels in the soil. In most cases, their feeding selections are widely varied. In the interest of the food preferences of E. proxima, we attempted to confirm how the Collembola utilize food when feeding on carrion (unusual sources). Four different so...
Phosphorus ore extraction for soil fertilization supports the demand of modern agriculture, but extractable resource limitations, due to scarcity, impose a P reuse and recycling research agenda. Here we propose to integrate biochar production (pyrogenic carbon) with municipal and agricultural waste management systems, to recover and reuse phosphoro...
An introduction to soil protist diversity for the beginner.
This revision of the classification of eukaryotes follows that of Adl et al., 2012 [J. Euk. Microbiol. 59(5)] and retains an emphasis on protists. Changes since have improved the resolution of many nodes in phylogenetic analyses. For some clades even families are being clearly resolved. As we had predicted, environmental sampling in the intervening...
Nutrient amendment increases plant productivity but the effects and mechanisms on soil organic carbon (SOC)
accumulation and stability remain unclear, especially in nutrient deficient alpine ecosystem. Here, based on an
experiment combining nitrogen (N) and phosphorus (P) input continuously for 15 years, we found that nutrient
amendment did not aff...
The Convention on Biological Diversity (CBD) commits its 196 nation parties to conserve biological diversity, use its components sustainably, and share fairly and equitably the benefits from the utilization of genetic resources. The last of these objectives was further codified in the Convention's Nagoya Protocol (NP), which came into effect in 201...
Protists include all eukaryotes except plants, fungi and animals. They are an essential, yet often forgotten, component of the soil microbiome. Method developments have now furthered our understanding of the real taxonomic and functional diversity of soil protists. They occupy key roles in microbial foodwebs as consumers of bacteria, fungi and othe...
The study examined the main and interactive effects of soil-applied fertilizers (nitrogen, phosphorus, and potassium) and optimum fertilizer rate for the vegetative and crop phases leaf nutrients and berry yields of wild blueberry (Vaccinium angustifolium Ait.). Data were collected between 2004 and 2010 from previous and ongoing nutrition studies t...
A book review of “Bibliometrics and Research Evaluation – uses and abuses” by Yves Gingras, 2016, MIT Press, Cambridge Mass. This is a summary of what I thought were the core ideas presented in this book, occasionally padded with my own comments. The main three metrics used in the evaluation of research impact that are the focus of the essay are th...
The bewildering organismal and functional complexity of microbial eukaryotes has long fascinated protistologists but exceeded the capacity of this research community to comprehensively study it. Lacking the critical mass for a strong scientific discipline, protistologists remain largely divided into various sub-communities (protozoology versus phyc...
p>Universal taxonomic frameworks have been critical tools to structure the fields of botany, zoology, mycology, and bacteriology as well as their large research communities. Animals, plants, and fungi have relatively solid, stable morpho-taxonomies built over the last three centuries, while bacteria have been classified for the last three decades u...
The study examined the main and interactive effects of soil-applied fertilizers [nitrogen (N), phosphorus (P), and potassium (K)] from a 12-year (six production cycles) field experiment conducted at Kemptown, Nova Scotia (Canada). It also recommends the optimum rate for improved growth and harvestable yield of wild blueberry (Vaccinium angustifoliu...
Key messages
• Soil is an important habitat for thousand millions of organisms.
• Soil biodiversity is extremely diverse in shapes, colours, sizes and functions.
• Soil biodiversity is globally distributed, from deserts to polar regions through grasslands, forests, urban and agricultural areas.
• Soil biodiversity supports many services essential t...
SPE EA Pôle BIOME The Atlas is divided in 8 chapters covering all the aspects of soil biodiversity: - Chapter I: The soil habitat - Chapter II: Diversity of soil organisms - Chapter III: Geographical and temporal distribution - Chapter IV: Ecosystem functions and services - Chapter V: Threats - Chapter VI: Interventions - Chapter VII: Policy, educa...
Soil plays a central role in the functioning of all terrestrial ecosystems. Among the many ecosystem services to which soil contributes are: purification and storage of water, sequestration of organic matter, nutrient cycling for plant growth, and conservation of healthy faunal and microbial populations. As such, soil quality is a key determinant o...
a b s t r a c t The aim of this study was to determine if organic management of fields promoted soil quality indicators compared to sustainably managed fields following best-management practice guidelines. Using a soil quality minimum data set, conventionally and organically managed commercial potato fields in eastern Canada were compared. Microbia...
Understanding trophic linkages within the soil food web (SFW) is hampered by its opacity, diversity, and limited niche adaptation. We need to expand our insight between the feeding guilds of fauna and not just count biodiversity. The soil fauna drive nutrient cycling and play a pivotal, but little understood role within both the carbon (C) and nitr...
Wild blueberry (Vaccinium angustifolium Ait.) plant is well adapted to orthic humo-ferric podzols. These soils are typically sandy, acidic (pH 3.9-5.5), highly leached, poorly buffered and have well developed organic horizons. Podzols are not naturally fertile. However, these soils can become quite productive with proper fertilizer application. In...
Parameters characterizing the structure of the decomposer food web, biomass of the soil microflora (bacteria and fungi) and soil micro-, meso- and macrofauna were studied at 14 non-reclaimed 1- 41-year-old post-mining sites near the town of Sokolov (Czech Republic). These observations on the decomposer food webs were compared with knowledge of vege...
