Calculated loading rates of trace metals into the three environmental compartments demonstrate that human activities now have major impacts on the global and regional cycles of most of the trace elements. There is significant contamination of freshwater resources and an accelerating accumulation of toxic metals in the human food chain.

Quantitative assessment of worldwide contamination of air, water and soils by trace metals

Biochar as a sorbent for contaminant management in soil and water: a review.

Scattered literature is harnessed to critically review the possible sources, chemistry, potential biohazards and best available remedial strategies for a number of heavy metals (lead, chromium, arsenic, zinc, cadmium, copper, mercury and nickel) commonly found in contaminated soils. The principles, advantages and disadvantages of immobilization, soil washing and phytoremediation techniques which are frequently listed among the best demonstrated available technologies for cleaning up heavy metal contaminated sites are presented. Remediation of heavy metal contaminated soils is necessary to reduce the associated risks, make the land resource available for agricultural production, enhance food security and scale down land tenure problems arising from changes in the land use pattern.

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Heavy Metals in Contaminated Soils: A Review of Sources, Chemistry, Risks and Best Available Strategies for Remediation

Summary
Mechanisms for C stabilization in soils have received much interest recently due to their relevance in the global C cycle. Here we review the mechanisms that are currently, but often contradictorily or inconsistently, considered to contribute to organic matter (OM) protection against decomposition in temperate soils: (i) selective preservation due to recalcitrance of OM, including plant litter, rhizodeposits, microbial products, humic polymers, and charred OM; (ii) spatial inaccessibility of OM against decomposer organisms due to occlusion, intercalation, hydrophobicity and encapsulation; and (iii) stabilization by interaction with mineral surfaces (Fe-, Al-, Mn-oxides, phyllosilicates) and metal ions. Our goal is to assess the relevance of these mechanisms to the formation of soil OM during different stages of decomposition and under different soil conditions. The view that OM stabilization is dominated by the selective preservation of recalcitrant organic components that accumulate in proportion to their chemical properties can no longer be accepted. In contrast, our analysis of mechanisms shows that: (i) the soil biotic community is able to disintegrate any OM of natural origin; (ii) molecular recalcitrance of OM is relative, rather than absolute; (iii) recalcitrance is only important during early decomposition and in active surface soils; while (iv) during late decomposition and in the subsoil, the relevance of spatial inaccessibility and organo-mineral interactions for SOM stabilization increases. We conclude that major difficulties in the understanding and prediction of SOM dynamics originate from the simultaneous operation of several mechanisms. We discuss knowledge gaps and promising directions of future research.

Stabilization of organic matter in temperate soils: mechanisms and their relevance under different soil conditions – a review

A review of soil heavy metal pollution from mines in China: pollution and health risk assessment.

Trace Elements in the Terrestrial Environment

1 Introduction- 2 Biogeochemical Processes Regulating Metal Behavior- 3 Bioavailability of Trace Metals- 4 Environmental Contamination and Regulation- 5 Ecological and Health Risks of Metals- 6 Risk Assessment and Management in Metal-Contaminated Sites- 7 Arsenic- 8 Cadmium- 9 Chromium- 10 Lead- 11 Mercury- 12 Boron- 13 Copper- 14 Manganese- 15 Molybdenum- 16 Zinc- 17 Nickel- 18 Selenium- 19 Other Trace Elements- Appendix A Tables- Appendix B Abbreviations, Acronyms, Symbols, and Terms- Appendix C Scientific Names for Plants and Animals- About the Author

Domy C. Adriano

Papers

Trace Elements in the Terrestrial Environment

Trace Elements in Terrestrial Environments: Biogeochemistry, Bioavailability, and Risks of Metals

Trace elements in terrestrial environments

Arsenic fractionation in soils using an improved sequential extraction procedure

Role of assisted natural remediation in environmental cleanup