Relative book review:Earth Surface Systems:Complexity，Order，and Scale

Earth Surface Systems: Complexity，Order，and Scale Jonathan D. Phillips. Blackwell Publishers，Oxford，1999，180 pp. ，43 figures ( combining 12 photos and 31 diagrams) . 4 tables and 63 equations.

Earth Surface Systems: Complexity，Order，and Scale，part of the Natural Environment series edited by Andrew Goudie and Heather Viles，was written to promote better understanding of the complexities and interactions of the phenomena that create earth surface systems. Phillips prefers to define whole systems rather than individual components，with emphasis on the way these systems behave and interact with other phenomena through both space and time. In simpler terms， he addresses the fundamental processes that drive earth surface systems and the problems of the simultaneous existence，within a single system，of both order and complexity. Phillips succinctly and clearly defines and explains the complexities of earth surface systems and the interrelations of many varied phenomena. The book is an important contribution to the geomorphic literature and should be a part of the library of any serious earth scientist.

The text consists of an introductory chapter followed by eight chapters describing various features and problems of earth surface systems. Numerous photographs and diagrams provide examples of the complexities of the subject. The photos and diagrams are enlarged and extend over the margins，which helps with visualization of the processes discussed. Citations to more detailed accounts of the topic of discussion are liberally inserted throughout the text. An extensive reference list provides ample opportunity for more interested readers to delve deeper into the problems and complexities of earth surface systems and processes.

The introductory chapter defines the author’s goals and describes the theoretical background behind his systematic approach to earth processes，rather than a “reductionist”or “nonlinear dynamic systems”approach. However，the author considers these other forms of knowledge to be complimentary to a systems approach rather than competitive，and draws upon reductionist and nonlinear systems dynamics research to support his ideas on many occasions. Phillips claims that reductionist approaches are necessary to fully understand the components of a system，and that nonlinear dynamics research is needed to understand the dynamics of complex systems.

The second chapter begins with a qualitative analysis of earth surface systems，but quickly delves into numerical methods for explaining these systems. The chapter is designed for earth scientists who suffer from math anxiety，and is useful for people with limited math experience. Phillips allows students unfamiliar with advanced numerical methods to grasp the basics of systems concepts in relatively simple mathematical terms. This simple approach to numerical modeling， combined with frequent summaries，is a useful learning tool.

Chapter Three describes both the order and complexity inherent in landscapes. Phillips provides many examples of the order found in complex systems and，conversely，complexity in orderly systems. The author argues that Earth surface systems are unstable by nature and that they exhibit both complex disorder and stable order at different scales. In simpler terms，complexity and order can exist within the same system at different spatial and temporal scales.

The fourth chapter provides brief examples that strengthen the argument that earth surface systems are unstable，often chaotic，and self-organizing. Phillips' assertions are based on a series of case studies and on empirical evidence，the properties of generalized canonical models， deterministic uncertainty，and differation and divergence.

Chapter Five specifically discusses the properties of generalized canonical models，including population and hillslope evolution models. This is the most extensive chapter of the text and includes four detailed case studies，each of which represents the complex interactions within a specific system: hydraulic geometry，channel network evolution，topographic relief evolution，and desertification. The spatial and temporal variability，and the disturbances that force a system into chaotic rather than a steady-state mode，are compared for each system. The author states，then elucidates the complexities and interrelations within each system. The case study examples include an excellent range of the earth’s geomorphic systems and focus on the complexities of changing time，scale，and input parameters. This chapter provides valuable insight into fluvial， landscape，and climate variables.

The role of pedogenesis，and particularly soils as earth surface systems，is the topic of Chapter Six. Phillips’claim that soils are the classic representation of earth surface systems is well supported with copious examples of the dynamics of soil types and variation within the mechanisms of soil formation. His concept that soils co-evolve with ecosystems，landforms，and other earth surface systems，allows generalizations concerning the behavior of soil systems to be applied to other earth surface systems.

In Chapter Seven，Phillips links his field observations with the concept of soils as a canonical example of earth surface systems. This chapter ties together the many and varied concepts that Phillips proposed in previous chapters，and is perhaps the most innovative and comprehensive chapter in the text. His own fieldwork has shown that instability，chaos，and self-organization are common phenomena in the Carolina Coastal Plain and similar results have been shown by investigations in other areas. The phenomena that produce chaotic patterns on the Carolina Coastal Plain are well known. Examples include the preservation of previous perturbations such as tree throw，bioturbation，and root casts. These rather small perturbations tend to persist and grow over time，eventually producing highly variable soil patterns over remarkably short distances. The same processes that control soil development also influence other systems.

The question of scale is significant for every geomorphology investigation and the problems related to scale are the focus of Chapter Eight. In this chapter，spatiotemporal scale relationships are linked to the necessity for understanding the rates，duration，and frequencies of the processes that act upon a system. Definition of these processes by any single nonlinear formula or complex systems analysis is not now，and may never be，possible. Phillips states that to fully understand earth surface systems，traveling into the field and measuring the distance，speed，population，and distribution of any such system is imperative.

In Chapter Nine，Phillips synthesizes his ideas and concepts by proposing eleven principles of earth surface systems，which clearly summarize the detailed descriptions found in the previous chapters. Reading this chapter before reading the entire text would greatly assist those readers who are not familiar with earth surface systems literature. By reading this chapter first，they would familiarize themselves with the major concepts that the author emphasizes and provide a better overall understanding of the book.

Amidst all of the strengths of this book，it is perhaps easier to define the few—but significant—weaknesses. Although the book is written for geographers，geologists，and other earth scientists who have a basic knowledge of physical geography，a more advanced knowledge of earth surface processes is required for complete understanding of the text. The book is more appropriate for advanced undergraduate or graduate students. Most undergraduate earth science majors would find this text overwhelming. The text is obscurely written and jargon-rich，and the absence of a glossary hinders the ease of use. The detail and complexity of the book make it difficult to read; however，it is a significant contribution to advanced earth scientists，and an in-depth examination is rewarding and a true eye-opener for all but the most advanced geomorphologists. Overall，the text is a significant contribution to the understanding of earth systems and is a must for the library of any individual who considers himself an earth scientist or physical geographer.