Investigating Potential Indicators Of Soil Health Through Microbiome Response To Environmental And Anthropogenic Stressors

Traditionally, the analysis of soil health has overlooked the biological component of soil due to poor understanding of connections between the microbiome and empirically measured soil health indicators. The purpose of this study was to assess the effects of environmental and anthropogenic stressors on the soil microbiome, with the aim of identifying measurable soil biological indicators. Chosen soils were examined under distinct conditions to evaluate the effect of selected environmental and anthropogenic stressors on the microbiome. Soil biological responses were analyzed via enzymatic response, microbial functional genes, and microbial community. Environmental factors such as soil moisture and organic matter showed significant influence on the microbiome with each selected biological indicator showing importance. Anthropogenic factors provided various responses dependent largely on the nature of the soil amendment. This study demonstrates that in addition to traditional soil health indicators, soil biological indicators should be included in the process of determining healthy soils.

Approaches to Soil Health Analysis A concise survey of soil health analysis and its various techniques and applications The maintenance of healthy soil resources provides the foundation for an array of global efforts and initiatives that affect humanity. Whether they are working to combat food shortages, conserve our ecosystems, or mitigate the impact of climate change, researchers and agriculturalists the world over must be able to correctly examine and understand the complex nature of this essential, fragile resource. These new volumes have been designed to meet this need, addressing the many dimensions of soil health analysis in chapters that are concise, accessible and applicable to the tasks at hand. Soil Health, Volume One: Approaches to Soil Health Analysis provides a well-rounded overview of the various methods and strategies available to analysists, and covers topics including: The history of soil health and its study Challenges and opportunities facing analysists Meta-data and its assessment Applications to forestry and urban land reclamation Future soil health monitoring and evaluation approaches Offering a far-reaching survey of this increasingly interdisciplinary field, this volume will be of great interest to all those working in agriculture, private sector businesses, non-governmental organizations (NGOs), academic-, state-, and federal-research projects, as well as state and federal soil conservation, water quality and other environmental programs.

1. Defining and assessing soil health and sustainable productivity 2. The relationship of soil health to ecosystem health 3. Rationale for developing bioindicators of soil health 4. Bioindicators: perspectives and potential for land users, researchers and policy makers 5. Soil microbial biomass, activity and nutrient cycling as indicators of soil health 6. Soil enzyme activities as integrative indicators of soil health 7. Soil microflora as bioindicators of soil health 8. Potential use of plant root pathogens as bioindicators of soil health 9. Soil microfauna as bioindicators of soil health 10. Community structure of soil arthropods as a bioindicator of soil health 11. Can the abundance or activity of soil macrofauna be used to indicate the biological health of soils? 12. Biodiversity of soil organisms as indicators of soil health 13. Biomonitoring of soil health by plants 14. Bioindicators to detect contamination of soils with special reference to heavy metals 15. Chemical and molecular approaches for rapid assessment of the biological status of soils 16. Use of genetically modified microbial biosensors for soil ecotoxicity testing 17. Biological indicators of soil health: synthesis.

V. 1 - Natural and anthropogenic organics; v. 2 - Metals, other inorganics, and microbial activities. General soil quality as influenced by interactions of soil minerals with organics and microorganisms: Organic-inorganic interections in soils and their effects on soil quality; Sorption phenomena between inorganic and organic compounds in soils: impacts on transformation processes; Role of aluminium and iron in the accumulation of organic matter in soils with variable charge; Sorption of ions by soil organic matter and clay-organics at low ionic strength; Water potential, soil microhabitats, and microbial development; Effect of citric acid on interlayer adsorption of hydroxy-aluminosilicate ions by montmorillonite; Microbial oxidation of pyrites in relation to its efficiency in alkali soil reclamation; Modification of gelation properties of colloidal solids from oil sands: extraction impact on fine tailings formation; Position paper of part I; Transformations of natural and anthropogenic organic compounds as affected by soil minerals and microorganisms: Natural organics; Recent advances in organomineral interactions: implications for carbon cycling and soil structure; The role of short-range ordered mineral colloids in abiotic transformations of organics components in the environment; Influence of pyrogallol on the catalytic action of iron and managenese oxides in amino acid transformation; Photochemical effect on the abiotic transformations of polyphenolics as catalyzed by Mn(IV) oxide; Potential of the supercitical fluid extraction technique for characterizing organic-inorganic interactions in soils; Dissolution and fractionation of calcium-bound and iron-and aluminium-bound humus in soils; Rhe quality of soil organic matter as characterized by soil CPMAS C-NMR, and Py-FIMS; Extracellular polysaccharides: an interface between microorganisms and soil constituents; Low-molecular-weigh aliphatic carboxylic acids in some andisols of Japan; Relationship between organic acids and microorganisms on a kong-term cropping site in southeastern Australia; Effect of the addition of plant residues on the mineralization of sulfur in Costa Rican soils; Anthropogenic organics: Sorption and biodegradation of organic contaminants in soils: conceptual representations of process coupling; The role of dissolved metals and metal-containing surfaces in catalyzing the hydrolysis of organic pollutants; The role of abiotic and biotic catalysts in the transformation of phenolic compounds; The role of abiotic interections with humic substances on the environmental impact of organic pollutants; Adsorption mechanisms and abiotic catalytic transformations of some agrochemicals by clay minerals; Interactions between manganese oxides and multiple ringed aromatic compounds; Mobility and persistence of metolachlor and terbuthylazine in field lysimeters; Soil-pesticide interactions and their impact on the volatilization process; Factors affecting the movements, reactions, and biotransformations ox xenobiotics; Effect of soil minerals on the microbial formation of enzymes and their possible use in remediation of chemically polluted sites; Position paper of part II; Effect of microorganisms on mobility of heavy metals in soils; Interactions of copper with soil humic substances; Adsorption of phosphate on variable charge minerals: competitive effect of organic ligands; Cadmium adsorption on the hydroxyaluminum-montmorillonite complex as influencend by oxalate; Influence of citrate on selenite sorption-desorption on short-range ordered aluminum hydroxides; Role of amorphous fe oxides in controlling retention of heavy metal elements in soils; Effect of natural organic matter and pH on the bioavailability of metal ions in soils; Seasonal changes of organic matter, pH, nitrogen and some metals in forest topsoils in Austria: a case study of two soils with and whithout a litter layer; Substituion of rock phosphate and legumes for commercial fertilizers; Effect of single and combined inoculation with azotobacter and VA mycorrhizal fungi on growth and mineral nutrient contents of maize and wheat plants; Position paper of part I; Interactions of clays with microorganisms and bacterial survival in soil: a physicochemical perspective; Enumeration, survival, and beneficial activities of microorganisms introduced into soil; Effects of clay minerals, oxyhydroxides, and humic matter on microbial communities of soil, sediment, and water; Activity, stability, and kinetc properties of enzymes immobilized on clay minerals and organomineral complexes; Influence of site conditions and heavy metals on enzyme activities of forest topsoils; Aluminum toxicity: a major stress for microbes in the environment; Biological response to contamination with pentachlorophenol and mercuric chloride in a high organic matter soil; Ecology of 2,4-D degradation in three palouse silt loam soils.

In this thesis I studied how long-term soil contamination affects microbial populations and processes, ecosystem properties and functional stability. I also investigated which parameters are suitable as indicators of soil quality in long-term contaminated soils. I found that contamination had a negative impact on many examined microbial parameters, e.g. biomasses, respiration and growth rate (Chapter 2). Some parameters like protozoan biomass and metabolic quotient did not show any effect of stress probably due to strong variation. No single parameter indicated effects of both stressors. Thus, a set of indicators is needed to assess the condition of contaminated soils. In chapter 3 I tested information indices as a tool to describe ecological succession in belowground ecosystems. I used data from a primary succession on the island of Schiermonnikoog. I found that the indices that describe both size and organization of ecosystem followed trends predicted by the theory, but at the same time they were strongly correlated with total system biomass. Therefore I could not say whether the observed trends reflect succession or simply the build up of biomass. However, analysis of relative indices that are independent of biomass and describe only the organization of the ecosystem, showed that succession occurred only in soils between 0 and 10 years old. Since other authors clearly have shown that there has been succession in these soils in, I conclude that the relative information indices are not sensitive indicators of succession. In contaminated soils, however, relative information indices were sensitive to stress caused by high concentrations of copper and by low pH (chapter 4). Stress affected the organization of belowground ecosystems as predicted by the theory. Stressed soils were more vulnerable to external perturbations and less efficient in processing energy than unstressed soils. As the relative information indices responded to stress in predictable manner and each of them revealed effects of both stresses I concluded that these indices are useful indicators of environmental stress. In contrary the absolute indices responded in unpredicted manner to stress and therefore are not suitable as indicators of stress. In chapters 5 and 6, I used “stress on stress” experiments to test the functional stability of soil respiration and bacterial growth rate to additional stress or disturbance in experimentally contaminated soils. The results described in Chapter 5 seemed to confirm the hypothesis that microbial processes in not-stressed soils are more stable to additional stress. The microbial processes showed different responses to disturbances (Chapter 6) than to stress (Chapter 5). In some cases stressed soils appeared to be more stable to additional disturbance than not-stressed soils, in other cases the opposite was found. In chapter 7, I tested the functional stability in a real field situation with zinc and cadmium pollution. In this experiment processes responded differently than in the former experiments. Probably the response of a process depends on whether a co-tolerance towards a given (subsequent) stress was developed during exposure to the first stress.

Despite the connections between soils and human health, there has not been a great amount of attention focused on this area when compared to many other fields of scientific and medical study. Soils and Human Health brings together authors from diverse fields with an interest in soils and human health, including soil science, geology, geography, biology, and anthropology to investigate this issue from a number of perspectives. The book includes a soil science primer chapter for readers from other fields, and discusses the ways the soil science community can contribute to improving our understanding of soils and human health. Features Discusses ways the soil science community can contribute to the improvement of soil health Approaches human health from a soils-focused perspective, covering the influence of soil conservation and contact with soil on human health Illustrates topics via case studies including arsenic in groundwater in Bangladesh; the use of Agent Orange in Vietnam; heavy metal contamination in Shipham, United Kingdom and Omaha, Nebraska, USA; and electronic waste recycling in China. In a scientific world where the trend has often been ever-increasing specialization and increasingly difficult communication between fields and subfields, the interdisciplinary nature of soils and human health studies presents a significant challenge going forward. Fields with an interest in soils and human health need to have increased cross-disciplinary communication and cooperation. This book is a step in the direction of accessibility and innovation, elucidating the state of knowledge in the meeting of soil and health sciences, and identifying places where more work is needed.

“Soil Health and Climate Change” presents a comprehensive overview of the concept of soil health, including the significance of key soil attributes and management of soil health in conventional and emerging land use systems in the context of climate change. Starting with a review of the physical, chemical and biological indicators of soil health and their significance for monitoring the impacts of climate change, this book then focuses on describing the role of soil structure, pH, organic matter, nitrogen, respiration and biota in sustaining the basic functions of soil ecosystems, and their anticipated responses to climate change. Further topics include the management of cropping, pastoral, and forestry systems, and rehabilitated mine sites, with a focus on mitigation of and adaptation to climate change impacts. Finally, the opportunities and potential risks of organic farming, biochar and bioenergy systems, and their ability to sustain and even enhance soil health, are discussed.

We are living in the era of climate change which becomes more complicated whenever some new environmental issue emerges only to get linked with this already existing challenge. Engineered nanoparticle (NP) contamination is of such issue which may become a major environmental problem under some circumstances in the decades to come. NP-based technologies have proven themselves useful and have the potential for greater promise, but they could become more than a nuisance. Unfortunately, very limited information is available on the environmental impacts of NPs in general and soil in particular. In this thesis, I examined the impact of NPs on soil microbial communities and by trying to avoid the presence of existing NPs I used soil from arctic regions. To examine the effect of another anthropogenic change on the same soil, I investigated the impacts of freeze-thaw cycles (FTCs). This thesis demonstrated that Ag-NPs and Cu-NPs cause a shift in microbial communities. The use of culture-dependent and culture-independent assessment techniques for microbial communities inspired the development of a toxicity indicator. This tool assigned the highest toxicity index to Ag-NPs and a low toxicity to SiO2-NPs. Supporting in vitro studies confirmed that Bradyrhizobium canariense was particularly sensitive towards Ag-NPs. Further analysis showed that a mixture of Ag-, Cu-, and SiO2-NPs were toxic. FTCs were also a significant stress; they had a differential impact upon soil communities derived from different arctic sites. My results suggest that the impact of climate change at high latitudes may not be predictable. Finally, I used a FTC regime shown not have an impact on low arctic sites and compared two different concentrations of Ag-NPs and Ag-microparticles and validated the higher toxicity impact of Ag-NPs on both bacterial and fungal communities. Taken together, these findings represent an initial attempt to try to understand the impacts of two stresses attributable to human activities on arctic soils, soils that are crucial to the health of our planet.