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Mediterranean-type ecosystems: The role of nutrients
Ecological Modelling, 28
(1985) 231-239 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands
231
Book Reviews
MEDITERRANEAN-TYPE ECOSYSTEMS
Mediterranean-Type Ecosystems: The Role of Nutrients. F.J. Kruger, D.T. Mitchell and J.U.M. Jarvis (Editors). Ecological Studies, 43. Springer, Berlin/Heidelberg, 1983. 552 pp., US$40.50. ISBN 3-540-12158-7. The five relatively small, isolated, mediterranean-climate zones of the earth, each with its distinct fauna and flora, have provided the ideal testing grounds for the theory of ecological convergence. Besides the Mediterranean Basin, comparative ecosystem studies have been made between the Australian heathlands and the South African fynbos, and the richer soils in Chile and California. The research studies show that the arrays of strategy-types to be found among the different biotas are so similar that they can only be explained in terms of the convergence hypothesis. Differences do exist in community organization and dynamics, especially phenology, so that resource availability and resource use patterns need to be studied to assess convergence at higher levels of organization than the population. The concept of a mediterranean climate biome has been challenged because major sclerophyllous shrublands - - the Australian heathlands and South African fynbos - - are determined by nutrients, not by climate. Both of these vegetation formations extend well beyond the boundaries of the mediterranean-type climates into the tropics and their distribution correlates with soils exceptionally poor in nutrients. This text is subdivided into six major sections. The first, on the evolution and characteristics of mediterranean-type ecosystems, proceeds from a review of the evolutionary history of the systems, through major features of vegetation-environment patterns to the question of detecting patterns in the geographic distribution of plant forms. General, predictable relations between the cover and stature of the evergreen overstorey that characterizes all mediterranean-type ecosystems, and water balance parameters for the site, are presented. No such relationships hold for the understorey; here, soil factors override climate. The second major section, on plant form and function, is aimed at assessing our understanding of how environment is functionally linked to plant forms. Although considerable progress has been made in recent years on studies of plant form and function in California and Chilean mediterranean-climate plants, little information is available on similar plants of South Africa and Australia.
232
The third section focuses on nutrient cycling. The first nutrient budgets of mediterranean-type ecosystems were done in southern France. A comprehensive comparative review for California and Chilean sclerophyllous shrublands has been recently compiled, but less is known about nutrient cycling than carbon balance. The pool sizes of phosphorus and nitrogen have been assessed for Australian heath and South African fynbos. Litter production in mediterranean-type ecosystems is generally lower than that of other ecosystems (e.g., savanna and tropical forest). Decomposition models based upon environmental variables and litter chemical composition are reviewed. Even though the mediterranean-type vegetation of California and Chile may have evolved by convergence on the basis of similar environmental conditions, the seasonal cycling of nutrients and mobile carbon pools of plant species from the same mediterranean regions showed little convergence. In the fourth section, on plant nutrition, data for mineral, nonstructural carbohydrates and fat content, and weighted concentrations and standing stocks are presented. The different adaptations that most plants from mediterranean South Africa and western Australia possess for maximizing nutrient uptake are described. The fifth section contains eight chapters that deal with community pattern and diversity, specifically how communities are structured in these resourcepoor environments, and how their dynamics contribute to maintenance of richness. Mediterranean-type shrublands, as a rule, are richer in plant species than are communities of adjoining plant communities. Some of the richest plant communities, and regional floras, in the world are found in these zones. The California Floristic Province, the South West Botanical Province of western Australia, and especially the Cape Floristic Kingdom have notably rich floras. The final section, on plant-animal interactions, has two chapters that concentrate on herbivory. The material for this text came from a series of conferences, but only selected material has been used, and a number of chapters are invited review papers. Certainly, the editors have done an excellent job of screening the material. The material is comprehensive and has been put together in textbook style rather than a conference proceedings. Congratulations! GAYLORD V. SKOGERBOE
International Irrigation Center, UMC 83 B, Utah State UnioerMty Logan, UT 84322, U.S.A.
(1985) 231-239 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands
231
Book Reviews
MEDITERRANEAN-TYPE ECOSYSTEMS
Mediterranean-Type Ecosystems: The Role of Nutrients. F.J. Kruger, D.T. Mitchell and J.U.M. Jarvis (Editors). Ecological Studies, 43. Springer, Berlin/Heidelberg, 1983. 552 pp., US$40.50. ISBN 3-540-12158-7. The five relatively small, isolated, mediterranean-climate zones of the earth, each with its distinct fauna and flora, have provided the ideal testing grounds for the theory of ecological convergence. Besides the Mediterranean Basin, comparative ecosystem studies have been made between the Australian heathlands and the South African fynbos, and the richer soils in Chile and California. The research studies show that the arrays of strategy-types to be found among the different biotas are so similar that they can only be explained in terms of the convergence hypothesis. Differences do exist in community organization and dynamics, especially phenology, so that resource availability and resource use patterns need to be studied to assess convergence at higher levels of organization than the population. The concept of a mediterranean climate biome has been challenged because major sclerophyllous shrublands - - the Australian heathlands and South African fynbos - - are determined by nutrients, not by climate. Both of these vegetation formations extend well beyond the boundaries of the mediterranean-type climates into the tropics and their distribution correlates with soils exceptionally poor in nutrients. This text is subdivided into six major sections. The first, on the evolution and characteristics of mediterranean-type ecosystems, proceeds from a review of the evolutionary history of the systems, through major features of vegetation-environment patterns to the question of detecting patterns in the geographic distribution of plant forms. General, predictable relations between the cover and stature of the evergreen overstorey that characterizes all mediterranean-type ecosystems, and water balance parameters for the site, are presented. No such relationships hold for the understorey; here, soil factors override climate. The second major section, on plant form and function, is aimed at assessing our understanding of how environment is functionally linked to plant forms. Although considerable progress has been made in recent years on studies of plant form and function in California and Chilean mediterranean-climate plants, little information is available on similar plants of South Africa and Australia.
232
The third section focuses on nutrient cycling. The first nutrient budgets of mediterranean-type ecosystems were done in southern France. A comprehensive comparative review for California and Chilean sclerophyllous shrublands has been recently compiled, but less is known about nutrient cycling than carbon balance. The pool sizes of phosphorus and nitrogen have been assessed for Australian heath and South African fynbos. Litter production in mediterranean-type ecosystems is generally lower than that of other ecosystems (e.g., savanna and tropical forest). Decomposition models based upon environmental variables and litter chemical composition are reviewed. Even though the mediterranean-type vegetation of California and Chile may have evolved by convergence on the basis of similar environmental conditions, the seasonal cycling of nutrients and mobile carbon pools of plant species from the same mediterranean regions showed little convergence. In the fourth section, on plant nutrition, data for mineral, nonstructural carbohydrates and fat content, and weighted concentrations and standing stocks are presented. The different adaptations that most plants from mediterranean South Africa and western Australia possess for maximizing nutrient uptake are described. The fifth section contains eight chapters that deal with community pattern and diversity, specifically how communities are structured in these resourcepoor environments, and how their dynamics contribute to maintenance of richness. Mediterranean-type shrublands, as a rule, are richer in plant species than are communities of adjoining plant communities. Some of the richest plant communities, and regional floras, in the world are found in these zones. The California Floristic Province, the South West Botanical Province of western Australia, and especially the Cape Floristic Kingdom have notably rich floras. The final section, on plant-animal interactions, has two chapters that concentrate on herbivory. The material for this text came from a series of conferences, but only selected material has been used, and a number of chapters are invited review papers. Certainly, the editors have done an excellent job of screening the material. The material is comprehensive and has been put together in textbook style rather than a conference proceedings. Congratulations! GAYLORD V. SKOGERBOE
International Irrigation Center, UMC 83 B, Utah State UnioerMty Logan, UT 84322, U.S.A.