Ecotoxicology and Chemistry Applications in Environmental Management

Book review by Rupert Purchase
Haywards Heath
ECG Bulletin February 2018

The author of this textbook, the ecologist Sven Erik Jørgensen (1934–2016), made many notable contributions to ecology and ecological modelling and management. In two influential books, Fundamentals of Ecological Modelling (fourth edition, 2011) and Towards a Thermodynamic Theory for Ecological Systems (2004), Jørgensen and co-authors outlined the roles of mathematics and physical chemistry in understanding ecosystems and the impact of toxicants on the environment. Jørgensen had editorial responsibilities for the journals Ecological Complexity and Ecological Monitoring, and was editor in chief for Encyclopedia of Ecology (2008).

Ecotoxicology and Chemistry Applications in Environmental Management, written when the author was Emeritus Professor in Environmental Chemistry at the University of Copenhagen, and is therefore a distillation of Jørgensen’s life’s work in ecology and environmental management. In chapter one, Jørgensen emphasises a holistic approach in understanding changes to ecosystems whether natural or anthropogenic in origin, and suggests seven management steps for integrated ecological and environmental management:

1. Define the problem.
   
2. Determine the ecosystems involved.
3. Find and quantify all the sources of the problem.
4. Set up a diagnosis to understand the relation between the problem and the sources.
5. Determine all the tools needed to implement and solve the problem.
6. Implement and integrate the selected solutions.
7. Follow the recovery process

In the subsequent fourteen chapters, Jørgensen characterises the properties and nature of pollutants, tools for modelling their environmental impact, and reviews some technological and societal solutions for environmental management. The longest chapter in the book concerns the application of the concepts of physical chemistry (essentially Gibbs’ thermodynamics) to understanding the distribution of anthropogenic chemicals in the environment. The author estimates that hundreds of thousands of chemicals participate in environmental chemistry. Their chemical properties determine their distribution in the lithosphere, hydrosphere, atmosphere, and technosphere (the technologically modified environment), and hence the environmental and health effects of these substances. Jørgensen explains the concepts of acid-base equilibria, buffer capacity, metal-ligand complex formation and stability constants, the application of Henry’s law for determining distribution between the atmosphere and hydrosphere, absorption isotherms, and redox chemistry. The author also provides fourteen worked examples to illustrate the application of these concepts. For example, how to calculate: (a) the [Ca²⁺] and [CO₃^2–] content of an open freshwater system in equilibrium with solid calcium carbonate and with carbon dioxide at a defined pressure; (b) the concentration of the hydroxo species Hg(OH)⁺ and Hg (OH)₂ in a lake of known total mercury concentration and pH.

In a chapter on the ‘Application of ecological models in environmental chemistry and ecotoxicology’, Jørgensen gives a lucid account of the construction and application of modelling in ecological and environmental management:

• ‘Models are synthesis of all what we know – observations, theoretical knowledge, knowledge about rates and sizes, knowledge about food items etc.
• Models are tools to overview complex systems. 
• Models make it possible to quantify by the use of mathematical formulations and computers.’

The author cites from the literature seventeen examples of ecosystems which have been modelled (e.g., lakes, open sea ecosystems, mountain ecosystems, etc.) and thirteen environmental problems (e.g. eutrophication, pollution by heavy metals, global warming and climate changes).

In a succeeding chapter on ecosystem health assessment (EHA), the author suggests that EHA and ecological monitoring are complementary tools in environmental management, and describes the criteria for the selection of ecological indicators for EHA and the classification of ecosystem health indicators.
The remaining chapters concern the application of engineering techniques in solving pollution problems. Three applications are distinguished:

1. Environmental engineering technologies (e.g. techniques for wastewater treatment).
2. The concept of ecological engineering – based on the work of US ecologist H. T. Odum (1924–2002) – for remediation, e.g. the construction of wetlands for the treatment of wastewater or diffuse pollution sources.
3. ‘Cleaner production’ techniques in environmental management. This area covers environmental auditing and environmental management systems, cleaner production techniques to reduce pollution and energy use, and ‘Green Chemistry’. 

In the concluding chapter, Jørgensen returns to the seven steps he proposed for environmental management at the start, suggesting that the application of techniques developed over the past 45 years, and expertly reviewed in this book, allows each of these steps to be accomplished. Tools at our disposal allow us to:

1. Identify the environmental problem both qualitatively and quantitatively.
2. Develop a diagnosis that relates the environmental problem and its effects and consequences.
3. Combine several toolboxes that offer solutions to the problem, to suggest a proper ecological–economical solution.

This book is highly recommended for students of environmental chemistry and should be available on the bookshelves of environmental managers. A more comprehensive Subject Index (and an Author Index) would have been welcome.

Reference
Sven Erik Jørgensen, Ecotoxicology and Chemistry Applications in Environmental Management, CRC Press, Boca Raton, FL, 2016, xiii + 304 pp. Part of a series of monographs, ‘Applied Ecology and Environmental Management’, Series Editors Sven Erik Jørgensen et al.; https://www.crcpress.com/Applied-Ecology-and-Environmental-Management/book-series/CRCAPPECOENV; accessed 25 November 2017.