Environmental Systems: An Introductory Text

Any book is a compromise between the original develop, as does its social and cultural context. aspirations of the author(s) and the realities of New research findings enhance understanding or publication. For this reason reviewers, are often open new avenues of endeavour, which, with in- able to take issue not so much with the substantive ductive reasoning, extend the frontiers of the field. content of a book, but with pragmatic decisions New paradigms emerge, and private and public imposed on authors by this need to compromise. attitudes and values change. In short, a book is an The first edition of this book was no exception, ephemeral entity, providing at best a synoptic for the breadth of its canvas made compromise picture: a particular view of the world which is inevitable if its focus on functioning environmental sooner or later out of date and superseded. The systems was not to be lost. Although, hopefully, it first edition of this book, however, was fortunate has proved to be a successful compromise, several in being a little ahead of its time in anticipating such decisions have been questioned, partly by some of the changes which have occurred since its reviewers, partly by feedback from students and publication. The preface to the first edition stated teachers using the book.

A A systems framework: to have a picture.- 1 Why a systems approach?.- 1.1 Humans, environment and geography.- 1.2 Systems.- 1.3 Environmental systems as energy systems.- 1.4 Systems and models.- 1.5 The application of the systems framework.- Further reading.- 2 Matter, force and energy.- 2.1 The nature of matter.- 2.2 Fundamental forces.- 2.3 Work and energy.- Further reading.- B A systems model: a partial view.- 3 Energy relationships.- 3.1 The closed-system model.- 3.2 The atmospheric system.- 3.3 Earth-surface systems.- 3.4 Energy balance of the Earth-atmosphere system.- 3.5 The Earth’s interior systems.- 3.6 Energy conversion.- Further reading.- 4 The atmosphere.- 4.1 Structure of the atmospheric system.- 4.2 The transfer of energy and mass in the atmospheric system.- 4.3 The primary circulation system: approximations to a successful model.- Further reading.- 5 The lithosphere.- 5.1 The crustal system.- 5.2 System structure.- 5.3 The crustal system: transfer of matter and energy.- 5.4 The implications of the geochemical model.- Further reading.- 6 The hydrosphere.- 6.1 Water in the Earth-atmosphere system.- 6.2 Chemistry of atmospheric water.- 6.3 The oceans.- 6.4 Chemistry of the land-based hydrosphere.- Further reading.- 7 The ecosphere.- 7.1 The biosphere and ecosphere.- 7.2 Structural organization of the biosphere.- 7.3 Functional organization and activity of the cell.- 7.4 The organism, the population and the community.- 7.5 A functional model of the ecosphere.- 7.6 Biogeochemical cycles.- 7.7 The ecosphere and the evolution of life.- Further reading.- C Open-system model refined: environmental systems.- 8 The atmosphere and the Earth’s surface.- 8.1 Introduction.- 8.2 The physical properties of a surface.- 8.3 Surface roughness.- 8.4 Topography.- 8.5 Surface-air interaction.- Further reading.- 9 Secondary and tertiary circulation systems.- 9.1 Secondary circulation systems.- 9.2 Tertiary circulation systems.- 9.3 Linkages between atmospheric systems.- Further reading.- 10 The catchment basin system.- 10.1 The structure of the catchment basin system: functional organization.- 10.2 System structure: spatial organization.- 10.3 System structure: material components.- 10.4 System function: energy flow.- 10.5 System function: material flows.- 10.6 Special cases of the model.- 10.7 Time, denudation and relief in the catchment basin system.- Further reading.- 11 The weathering system.- 11.1 A process-response model of the weathering system.- 11.2 The final state of the system: the regolith.- 11.3 The generalization of the model: other rock types.- 11.4 Exogenous variables and the control of weathering.- 11.5 Conclusion: further perspectives on weathering.- Further reading.- 12 The slope system.- 12.1 The initial state of the system.- 12.2 The operation of the slope system: the transfer of water.- 12.3 The operation of the slope system: the transfer of minerals.- 12.4 The balance of slope process and slope form.- 12.5 Complexity of hillslope process-form relationships.- 12.6 Conclusion.- Further reading.- 13 The fluvial system.- 13.1 Energy and mass transfer in channel systems.- 13.2 Channel dynamics: flow of water.- 13.3 Channel dynamics: erosion and transportation processes.- 13.4 Depositional processes.- 13.5 Stream power and the threshold of critical power.- 13.6 Channel form.- Further reading.- 14 The glacial system.- 14.1 Glaciers and the environment.- 14.2 System function.- 14.3 The transfer of mass: glacier flow.- 14.4 Glacier morphology.- 14.5 Erosion processes.- 14.6 Transfer of materials: transportation by glaciers.- 14.7 Deposition processes.- Further reading.- 15 The aeolian system.- 15.1 Introduction.- 15.2 Aeolian sediment movement.- 15.3 Erosion by wind.- 15.4 Aeolian deposition.- 15.5 Aeolian bedform morphology.- 15.6 Conclusion.- Further reading.- 16 The coastal system.- 16.1 Sources of energy in the coastal system.- 16.2 Materials in the coastal system.- 16.3 Nearshore dynamics: the interaction between water and coastal sediments.- 16.4 Coastal erosion.- 16.5 Coastal deposition.- 16.6 Conclusion.- Further reading.- 17 Spatial variations in the denudation system.- 17.1 Spatial variations in denudation output.- 17.2 Individual factors controlling denudation.- 17.3 Spatial variation in denudation system form.- 17.4 Relations between denudation processes and landscape form.- Further reading.- 18 The ecosystem.- 18.1 The ecosystem concept.- 18.2 The structural organization of the ecosystem.- 18.3 Functional activity of the ecosystem: the transfer of energy and matter.- 18.4 The ecological organization of space: the ecology of landscape.- Further reading.- 19 The primary production system.- 19.1 Functional organization and activity of the green plant.- 19.2 Ecosystem primary production.- 19.3 Regulation and limits to photosynthesis and primary production.- 19.4 Geographical variation and comparison of ecosystem primary production.- Further reading.- 20 The grazing-predation system.- 20.1 The heterotroph.- 20.2 Modelling ecosystem animal production.- 20.3 Energy flow and population regulation.- Further reading.- 21 The detrital system.- 21.1 Decomposition, weathering and the soil.- 21.2 The input to the detrital system: the supply of organic matter.- 21.3 Decomposition: a process-response model.- 21.4 Decomposition: a trophic model and the pathway of energy flow.- 21.5 Decomposition: a pedological model.- Further reading.- 22 The soil system.- 22.1 Defining the soil system.- 22.2 The control and regulation of pedogenesis.- 22.3 Formal processes of pedogenesis.- Further reading.- D Systems and change.- 23 Change in environmental systems.- 23.1 Equilibrium concepts.- 23.2 Thermodynamics, equilibrium and change.- 23.3 Manifestation of change.- 24 Change in physical systems.- 24.1 Change in climatic systems.- 24.2 Feedback mechanisms.- 24.3 The form of change.- 24.4 Zonal and dynamic change in the denudation system.- Further reading.- 25 Change in living systems.- 25.1 Inherent change in the ecosystem.- 25.2 Cliseral change.- 25.3 Evolutionary change.- Further reading.- 26 Human modification of environmental systems.- 26.1 Deforestation.- 26.2 Agriculture.- 26.3 Urbanization and industrialization.- 26.4 Control of environmental systems by humans: some examples.- Further reading.- 27 Systems retrospect and prospect.- References.