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Matthias C. Rillig

Bio: Matthias C. Rillig is an academic researcher from Free University of Berlin. The author has contributed to research in topics: Soil biology & Soil water. The author has an hindex of 98, co-authored 439 publications receiving 33692 citations. Previous affiliations of Matthias C. Rillig include Carnegie Institution for Science & San Diego State University.


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Journal ArticleDOI
TL;DR: A review of the literature reveals a significant number of early studies on biochar-type materials as soil amendments either for managing pathogens, as inoculant carriers or for manipulative experiments to sorb signaling compounds or toxins as mentioned in this paper.
Abstract: Soil amendment with biochar is evaluated globally as a means to improve soil fertility and to mitigate climate change. However, the effects of biochar on soil biota have received much less attention than its effects on soil chemical properties. A review of the literature reveals a significant number of early studies on biochar-type materials as soil amendments either for managing pathogens, as inoculant carriers or for manipulative experiments to sorb signaling compounds or toxins. However, no studies exist in the soil biologyliterature that recognize the observed largevariations ofbiochar physico-chemical properties. This shortcoming has hampered insight into mechanisms by which biochar influences soil microorganisms, fauna and plant roots. Additional factors limiting meaningful interpretation of many datasets are the clearly demonstrated sorption properties that interfere with standard extraction procedures for soil microbial biomass or enzyme assays, and the confounding effects of varying amounts of minerals. In most studies, microbial biomass has been found to increase as a result of biochar additions, with significant changes in microbial community composition and enzyme activities that may explain biogeochemical effects of biochar on element cycles, plant pathogens, and crop growth. Yet, very little is known about the mechanisms through which biochar affects microbial abundance and community composition. The effects of biochar on soil fauna are even less understood than its effects on microorganisms, apart from several notable studies on earthworms. It is clear, however, that sorption phenomena, pH and physical properties of biochars such as pore structure, surface area and mineral matter play important roles in determining how different biochars affect soil biota. Observations on microbial dynamics lead to the conclusion of a possible improved resource use due to co-location of various resources in and around biochars. Sorption and therebyinactivation of growth-inhibiting substances likelyplaysa rolefor increased abundance of soil biota. No evidence exists so far for direct negative effects of biochars on plant roots. Occasionally observed decreases in abundance of mycorrhizal fungi are likely caused by concomitant increases in nutrient availability,reducing theneedfor symbionts.Inthe shortterm,therelease ofavarietyoforganic molecules from fresh biochar may in some cases be responsible for increases or decreases in abundance and activity of soil biota. A road map for future biochar research must include a systematic appreciation of different biochar-types and basic manipulative experiments that unambiguously identify the interactions between biochar and soil biota.

3,612 citations

Journal ArticleDOI
TL;DR: It is argued that soil aggregation should be included in a more complete 'multifunctional' perspective of mycorrhizal ecology, and that in-depth understanding of myCorrhizas/soil process relationships will require analyses emphasizing feedbacks between soil structure and mycor Rhizas, rather than a uni-directional approach simply addressing mycorRhizal effects on soils.
Abstract: In addition to their well-recognized roles in plant nutrition and communities, mycorrhizas can influence the key ecosystem process of soil aggregation. Here we review the contribution of mycorrhizas, mostly focused on arbuscular mycorrhizal fungi (AMF), to soil structure at various hierarchical levels: plant community; individual root; and the soil mycelium. There are a suite of mechanisms by which mycorrhizal fungi can influence soil aggregation at each of these various scales. By extension of these mechanisms to the question of fungal diversity, it is recognized that different species or communities of fungi can promote soil aggregation to different degrees. We argue that soil aggregation should be included in a more complete 'multifunctional' perspective of mycorrhizal ecology, and that in-depth understanding of mycorrhizas/soil process relationships will require analyses emphasizing feedbacks between soil structure and mycorrhizas, rather than a uni-directional approach simply addressing mycorrhizal effects on soils. We finish the discussion by highlighting new tools, developments and foci that will probably be crucial in further understanding mycorrhizal contributions to soil structure.

1,394 citations

Journal ArticleDOI
TL;DR: The pervasive microplastic contamination as a potential agent of global change in terrestrial systems is introduced, the physical and chemical nature of the respective observed effects are highlighted, and the broad toxicity of nanoplastics derived from plastic breakdown is discussed.
Abstract: Microplastics (plastics < 5 mm, including nanoplastics which are < 0.1 μm) originate from the fragmentation of large plastic litter or from direct environmental emission. Their potential impacts in terrestrial ecosystems remain largely unexplored despite numerous reported effects on marine organisms. Most plastics arriving in the oceans were produced, used, and often disposed on land. Hence, it is within terrestrial systems that microplastics might first interact with biota eliciting ecologically relevant impacts. This article introduces the pervasive microplastic contamination as a potential agent of global change in terrestrial systems, highlights the physical and chemical nature of the respective observed effects, and discusses the broad toxicity of nanoplastics derived from plastic breakdown. Making relevant links to the fate of microplastics in aquatic continental systems, we here present new insights into the mechanisms of impacts on terrestrial geochemistry, the biophysical environment, and ecotoxicology. Broad changes in continental environments are possible even in particle-rich habitats such as soils. Furthermore, there is a growing body of evidence indicating that microplastics interact with terrestrial organisms that mediate essential ecosystem services and functions, such as soil dwelling invertebrates, terrestrial fungi, and plant-pollinators. Therefore, research is needed to clarify the terrestrial fate and effects of microplastics. We suggest that due to the widespread presence, environmental persistence, and various interactions with continental biota, microplastic pollution might represent an emerging global change threat to terrestrial ecosystems.

1,112 citations

Journal ArticleDOI
TL;DR: In this paper, the authors focus on biochar effects on mycorrhizal associations, and examine hypotheses pertaining to four mechanisms by which biochar could influence mycRH abundance and/or functioning.
Abstract: Experiments suggest that biomass-derived black carbon (biochar) affects microbial populations and soil biogeochemistry. Both biochar and mycor- rhizal associations, ubiquitous symbioses in terrestrial ecosystems, are potentially important in various ecosystem services provided by soils, contributing to sustainable plant production, ecosystem restoration, and soil carbon sequestration and hence mitigation of global climate change. As both biochar and mycor- rhizal associations are subject to management, under- standing and exploiting interactions between them could be advantageous. Here we focus on biochar effects on mycorrhizal associations. After reviewing the experimental evidence for such effects, we critically examine hypotheses pertaining to four mechanisms by which biochar could influence mycorrhizal abundance and/or functioning. These mechanisms are (in decreas- ing order of currently available evidence supporting them): (a) alteration of soil physico-chemical proper- ties; (b) indirect effects on mycorrhizae through effects on other soil microbes; (c) plant-fungus signaling interference and detoxification of allelochemicals on biochar; and (d) provision of refugia from fungal grazers. We provide a roadmap for research aimed at testing these mechanistic hypotheses.

1,093 citations

Journal ArticleDOI
TL;DR: The lack of knowledge on microplastic in soil is surprising given that the occurrence of larger plastic fragments in soils per se is nothing new, and has in fact been a trait used to describe urban soils or Technosols.
Abstract: W live in a “plastic age” with more than 240 million tons of plastic used annually, the majority of which for disposable use. Due to limited recovery of discarded materials and its durability, plastic debris is accumulating in the environment. Recently, research on environmental impacts of plastic has acquired a new dimension through the discovery and study of microplastic, particles often defined as smaller than 1 mm, but that are often in the range of several micrometers. These microplastics present a new set of issues, because of two main reasons: (i) they are small enough to be taken up by biota and thus can accumulate in the food chain; and (ii) they can sorb pollutants on their surfaces, thus enriching them on these particles. The occurrence of microplastic materials has been studied almost exclusively in marine environments and, related to this, on shorelines. Yet the terrestrial landmasses are conspicuously empty on maps of global microplastic distribution: they have simply not been studied. Why have microplastics not been studied in soils and terrestrial systems? First, there is a separation between marine and terrestrial ecological research such that ideas do not easily propagate from one domain to the other. Also important is the comparative ease with which microplastic filaments can be extracted and quantified from water. This is not so straightforward for the complex organo−mineral soil matrix. Also, there is a pattern of accumulation along shorelines, which has no parallel in terrestrial systems. Finally, aquatic environments harbor many filter-feeders, a mode of nutrition that will make organisms particularly susceptible to accumulating harmful particles from a large volume of the environment. Still, our lack of knowledge on microplastic in soil is surprising given that the occurrence of larger plastic fragments in soils per se is nothing new, and has in fact been a trait used to describe urban soils or Technosols. Microplastic can occur in the environment either as primary or secondary microplastics. Particles can enter the environment directly as primary microplastic: microplastics are manufactured for a number of purposes, such as for use as industrial abrasives or for cosmetics products. In contrast, secondary microplastics are produced through the environmental degradation of larger-sized pieces. Secondary microplastics could result from abrasion of plastic debris at soil surfaces (where UV light could render the material brittle) or inside the soil profile. In agricultural fields where plastic mulching is practiced, an abundant source of plastic material would be available; in other cases, incidental plastic debris would be the starting material. Curiously, even washing machines can produce secondary microplastic fibers; via water treatment plants these could end up on agricultural fields. It is tempting to speculate that tumble driers could also be a possible source of microplastics. Very small particles or fibers could be spread further by becoming air-borne (for example from landfills, or other surface deposits) and then enter terrestrial systems and the soil through atmospheric deposition. Geophagous soil fauna, most notably earthworms, could contribute to secondary microplastic formation: in their gizzard, they may grind up brittle plastic debris that they ingest into microplastic. Anecic earthworms, such that produce vertical burrows but feed near the soil surface, could even additionally promote incorporation of surface-deposited plastic pieces into the soil. Other soil mesofauna (such as collembola or mites) may also contribute to this breakdown by incidentally scraping or chewing off pieces of plastic. Also digging mammals, such as gophers or moles, could conceivably contribute to abrasion and incorporation into the soil. The actual direct, quantitative evidence of microplastic occurrence in soil is very thin. One study found synthetic fibers in several soils in the U.S. to which organic waste material had been applied. Others have found spectra in their soil organic matter analyses that are consistent with the presence of different types of plastic, but natural sources could not be completely ruled out. Many studies have just reported the presence of plastic in soil, but have not quantified the amount, nor described the size of the particles. Given that microplastic likely is in our soils, can it have adverse effects? Obviously, soil is quite different from oceans, but soil also contains many features of an aquatic system: many biota are essentially aquatic, thriving in a thin film of water covering soil surfaces. Thus, some of the same principles apply. Of course the soil also has its filter feeders, active on the water films on soil surfaces, like ciliates and rotifers; these similarly

916 citations


Cited by
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Journal ArticleDOI
TL;DR: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols used xiii 1.
Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

14,171 citations

Journal ArticleDOI
TL;DR: By identifying and synthesizing dispersed data on production, use, and end-of-life management of polymer resins, synthetic fibers, and additives, this work presents the first global analysis of all mass-produced plastics ever manufactured.
Abstract: Plastics have outgrown most man-made materials and have long been under environmental scrutiny. However, robust global information, particularly about their end-of-life fate, is lacking. By identifying and synthesizing dispersed data on production, use, and end-of-life management of polymer resins, synthetic fibers, and additives, we present the first global analysis of all mass-produced plastics ever manufactured. We estimate that 8300 million metric tons (Mt) as of virgin plastics have been produced to date. As of 2015, approximately 6300 Mt of plastic waste had been generated, around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. If current production and waste management trends continue, roughly 12,000 Mt of plastic waste will be in landfills or in the natural environment by 2050.

7,707 citations

01 Jan 1980
TL;DR: In this article, the influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition and found that the variability of the relationship between the δ^(15)N values of animals and their diets is greater for different individuals raised on the same diet than for the same species raised on different diets.
Abstract: The influence of diet on the distribution of nitrogen isotopes in animals was investigated by analyzing animals grown in the laboratory on diets of constant nitrogen isotopic composition. The isotopic composition of the nitrogen in an animal reflects the nitrogen isotopic composition of its diet. The δ^(15)N values of the whole bodies of animals are usually more positive than those of their diets. Different individuals of a species raised on the same diet can have significantly different δ^(15)N values. The variability of the relationship between the δ^(15)N values of animals and their diets is greater for different species raised on the same diet than for the same species raised on different diets. Different tissues of mice are also enriched in ^(15)N relative to the diet, with the difference between the δ^(15)N values of a tissue and the diet depending on both the kind of tissue and the diet involved. The δ^(15)N values of collagen and chitin, biochemical components that are often preserved in fossil animal remains, are also related to the δ^(15)N value of the diet. The dependence of the δ^(15)N values of whole animals and their tissues and biochemical components on the δ^(15)N value of diet indicates that the isotopic composition of animal nitrogen can be used to obtain information about an animal's diet if its potential food sources had different δ^(15)N values. The nitrogen isotopic method of dietary analysis probably can be used to estimate the relative use of legumes vs non-legumes or of aquatic vs terrestrial organisms as food sources for extant and fossil animals. However, the method probably will not be applicable in those modern ecosystems in which the use of chemical fertilizers has influenced the distribution of nitrogen isotopes in food sources. The isotopic method of dietary analysis was used to reconstruct changes in the diet of the human population that occupied the Tehuacan Valley of Mexico over a 7000 yr span. Variations in the δ^(15)C and δ^(15)N values of bone collagen suggest that C_4 and/or CAM plants (presumably mostly corn) and legumes (presumably mostly beans) were introduced into the diet much earlier than suggested by conventional archaeological analysis.

5,548 citations

01 Jan 2016
TL;DR: The modern applied statistics with s is universally compatible with any devices to read, and is available in the digital library an online access to it is set as public so you can download it instantly.
Abstract: Thank you very much for downloading modern applied statistics with s. As you may know, people have search hundreds times for their favorite readings like this modern applied statistics with s, but end up in harmful downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some harmful virus inside their laptop. modern applied statistics with s is available in our digital library an online access to it is set as public so you can download it instantly. Our digital library saves in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the modern applied statistics with s is universally compatible with any devices to read.

5,249 citations

Journal ArticleDOI
11 Jun 2004-Science
TL;DR: This work shows how aboveground and belowground components are closely interlinked at the community level, reinforced by a greater degree of specificity between plants and soil organisms than has been previously supposed.
Abstract: All terrestrial ecosystems consist of aboveground and belowground components that interact to influence community- and ecosystem-level processes and properties. Here we show how these components are closely interlinked at the community level, reinforced by a greater degree of specificity between plants and soil organisms than has been previously supposed. As such, aboveground and belowground communities can be powerful mutual drivers, with both positive and negative feedbacks. A combined aboveground-belowground approach to community and ecosystem ecology is enhancing our understanding of the regulation and functional significance of biodiversity and of the environmental impacts of human-induced global change phenomena.

3,683 citations