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Dynamic Biogeography
BOOK REVIEWS
181
agriculture". An experimental area of one hectare was studied with, in 1976, cutting and burning, and from 1977 to 1980, cultivation, and then returned to spontaneous vegetation (until 1982). The productivity and dynamics of nutrients (Ca, K, Mg . . . . ) is measured on cultivated areas and on reference areas. It appears that the productivity of cultures declines during three years of observation, falling from 4.31 to 2 tonnes per hectare (fresh weight of edible roots of yuca). The concentration of nutrients in the soil remains high, however, though a drop in pH influenced phosphorus availability. Nevertheless the total productivity of the ecosystem decreases less and that of weeds increases. Chapter 6 is concerned with the evolution of productivity and the dynamics of nutrients after cultivation has ceased. It is observed that productivity increases very quickly in the following three years. In the parcel cut and burnt but not cultivated, recovery is also quick and productivity, during the fourth year, is even superior to that of the unspoilt forest. Chapter 7 is entitled "Implications for management". For the author, the two most important results of this survey for management of the tropical forest on poor fertility soil are: "(a) Litter and other organic material on the soil surface are important for a continuing supply of nutrients and sustained crop growth. Management should aim toward maximizing soil organic matter. Practises which destroy soil organic matter should be minimized." "(b) Native trees are able to grow in soil with nutrient levels too low for the crops. This means that management plans that include utilization of native tree species are more likely to be successful for sustained production." These results are indeed very important but have been known for a long time. Perhaps this new confirmation will be useful in causing the authorities of States possessing responsibility for Amazon territories to think about the matter. The appendices A to C which describe the measurement methods used show that these were carried out with considerable care, despite some unforeseen happenings-monkeys knocked over the rain funnels at the meteorological station !--from 1976 to 1982. But why wait until 1989 to publish this synthesis? At this rate, the Amazon will be completely destroyed when, in San Carlos, they continue to measure Ca ions and watch birds for a week. Just a little final remark: in the "Bibliography", the references in French (five out of more than 250) are all mis-spelfl Even in Unesco, French is considered as a second zone language like Swahili and Brooklyn slang!
Dynamic Biogeography: R Hengeveld. Cambridge University Press, Cambridge, 1990. 250 pp. ISBN 0-521-38058-8. Price $54.50. I like this kind of book published in England with the publisher informing us that he received permission to print from King Henry VIII in 1524! The author of "Dynamic Biogeography', R. Hengeveld, accords with this ancient tradition. In former times, the author dedicated his work to the Queen, to Monseigneur le Dauphin or to the Archbishop of Canterbury. R. Hengeveld addresses his study, more modestly but more exactly, "to my parents"; this is more logical, the precise meeting of an ovule and a spermatozoon having indeed finally led to the book "Dynamic Biogeography'. But the author wishes not only to do honour to his parents but also to greet his friends: a certain Victor Westhoff who told him he ought to write this book, John Birks who made "innumerable English corrections", plus a series of Doctors, Professors and Librarians. With such full particulars in the preamble, it is page 16 before we come to the Introduction !
182
BOOK REVIEWS
The Introduction itself is classic: it defines what "Dynamic Biogeography" is. It does not differ greatly from the older "Biogeography", except for the adjective "Dynamic", which has a modern, fashionable connotation. Everything is "dynamic" nowadays, even electric irons. The chapter that follows is headed "Topics". There we learn that biogeographers should devote more attention to physiology, morphology, ethology, genetics, ecology, climatology and data processing. It is to be hoped that biogeographers have not waited for this book before doing that. One then finally arrives at the first part of the book, entitled "Patterns of Concordance". In five chapters, one of which consists of just one page (a record!), the respective merits of classification and data processing techniques are discussed, with examples from 1856 to our own times. Figure 6 on page 28 is exquisite, it consists solely of eleven horizontal lines and one vertical one! It helps to understand an arbitrary division! The second part is devoted to "Geographical trends in species richness and biological traits". A series of examples shows the quandary in which biogeographers find themselves when it comes to finding biological variables in relation to the distribution of species; from the size of genomes to photosynthetic activity. But, as the author says, "it is difficult to know whether adaptation is evolutionary, spatial or both". And he realizes that, unfortunately, "species appear to be subject to many ecological factors affecting many different traits and operating at a variety of scales". Obviously, that is prejudicial to biogeographers' research work. The third part is "Areography: the analysis of species range". There are numerous examples and maps here. One feels that biogeographers are on their "home ground", though this does not prevent the author from forgetting to put the units in ordinate in Figure 52, page 182. We learn that "species distributions are dynamic entities over long or short time scales and can be considered as outcomes of a process of perpetual adaptation to changeable conditions", which is just what Aristotle said. The fourth part is devoted to "Species ranges and patterns of concordance", where the author rightly remarks that there are discontinuous variations in time and space. One of the techniques recommended to biogeographers, in solving problems linked with those variations, is spectral and harmonic analysis. This approach seems quite worthwhile, since it shows that the west of the Rocky Mountains is characterized by rainy winters and, even more sensational, "occasionally this changes seasonally over short distances, as a sharp dividing line between two regimes lying, for example, in Southern Utah and Southern Nevada, near Arizona", which is not very precise from the (bio)geographical point of view. In Chapter 13, the author talks of the future. For him, the two most profitable lines of research will be: "analysis of the eco-physiological basis of species ranges, species nests, etc. and the analysis of population genetic, demographic and spatial processes concerning the dynamics of species ranges". How fortunate that a dynamic bio geographer confirms for us the interest of this dual scientific approach! In conclusion, this book is nevertheless very interesting and can be useful for students. And to finish in the style of the author, I dedicate this amicable review to Pa' and Ma' and I thank my IBM Writing Assistant for the automatic correction of all my spelling mistakes. Dr R. TERCAFS Senior Research Associate of the Belgium National Fund of Scientific Research University of Li#ge Sart Tilman BatTment B 11 B-4000 Liege Belgium
181
agriculture". An experimental area of one hectare was studied with, in 1976, cutting and burning, and from 1977 to 1980, cultivation, and then returned to spontaneous vegetation (until 1982). The productivity and dynamics of nutrients (Ca, K, Mg . . . . ) is measured on cultivated areas and on reference areas. It appears that the productivity of cultures declines during three years of observation, falling from 4.31 to 2 tonnes per hectare (fresh weight of edible roots of yuca). The concentration of nutrients in the soil remains high, however, though a drop in pH influenced phosphorus availability. Nevertheless the total productivity of the ecosystem decreases less and that of weeds increases. Chapter 6 is concerned with the evolution of productivity and the dynamics of nutrients after cultivation has ceased. It is observed that productivity increases very quickly in the following three years. In the parcel cut and burnt but not cultivated, recovery is also quick and productivity, during the fourth year, is even superior to that of the unspoilt forest. Chapter 7 is entitled "Implications for management". For the author, the two most important results of this survey for management of the tropical forest on poor fertility soil are: "(a) Litter and other organic material on the soil surface are important for a continuing supply of nutrients and sustained crop growth. Management should aim toward maximizing soil organic matter. Practises which destroy soil organic matter should be minimized." "(b) Native trees are able to grow in soil with nutrient levels too low for the crops. This means that management plans that include utilization of native tree species are more likely to be successful for sustained production." These results are indeed very important but have been known for a long time. Perhaps this new confirmation will be useful in causing the authorities of States possessing responsibility for Amazon territories to think about the matter. The appendices A to C which describe the measurement methods used show that these were carried out with considerable care, despite some unforeseen happenings-monkeys knocked over the rain funnels at the meteorological station !--from 1976 to 1982. But why wait until 1989 to publish this synthesis? At this rate, the Amazon will be completely destroyed when, in San Carlos, they continue to measure Ca ions and watch birds for a week. Just a little final remark: in the "Bibliography", the references in French (five out of more than 250) are all mis-spelfl Even in Unesco, French is considered as a second zone language like Swahili and Brooklyn slang!
Dynamic Biogeography: R Hengeveld. Cambridge University Press, Cambridge, 1990. 250 pp. ISBN 0-521-38058-8. Price $54.50. I like this kind of book published in England with the publisher informing us that he received permission to print from King Henry VIII in 1524! The author of "Dynamic Biogeography', R. Hengeveld, accords with this ancient tradition. In former times, the author dedicated his work to the Queen, to Monseigneur le Dauphin or to the Archbishop of Canterbury. R. Hengeveld addresses his study, more modestly but more exactly, "to my parents"; this is more logical, the precise meeting of an ovule and a spermatozoon having indeed finally led to the book "Dynamic Biogeography'. But the author wishes not only to do honour to his parents but also to greet his friends: a certain Victor Westhoff who told him he ought to write this book, John Birks who made "innumerable English corrections", plus a series of Doctors, Professors and Librarians. With such full particulars in the preamble, it is page 16 before we come to the Introduction !
182
BOOK REVIEWS
The Introduction itself is classic: it defines what "Dynamic Biogeography" is. It does not differ greatly from the older "Biogeography", except for the adjective "Dynamic", which has a modern, fashionable connotation. Everything is "dynamic" nowadays, even electric irons. The chapter that follows is headed "Topics". There we learn that biogeographers should devote more attention to physiology, morphology, ethology, genetics, ecology, climatology and data processing. It is to be hoped that biogeographers have not waited for this book before doing that. One then finally arrives at the first part of the book, entitled "Patterns of Concordance". In five chapters, one of which consists of just one page (a record!), the respective merits of classification and data processing techniques are discussed, with examples from 1856 to our own times. Figure 6 on page 28 is exquisite, it consists solely of eleven horizontal lines and one vertical one! It helps to understand an arbitrary division! The second part is devoted to "Geographical trends in species richness and biological traits". A series of examples shows the quandary in which biogeographers find themselves when it comes to finding biological variables in relation to the distribution of species; from the size of genomes to photosynthetic activity. But, as the author says, "it is difficult to know whether adaptation is evolutionary, spatial or both". And he realizes that, unfortunately, "species appear to be subject to many ecological factors affecting many different traits and operating at a variety of scales". Obviously, that is prejudicial to biogeographers' research work. The third part is "Areography: the analysis of species range". There are numerous examples and maps here. One feels that biogeographers are on their "home ground", though this does not prevent the author from forgetting to put the units in ordinate in Figure 52, page 182. We learn that "species distributions are dynamic entities over long or short time scales and can be considered as outcomes of a process of perpetual adaptation to changeable conditions", which is just what Aristotle said. The fourth part is devoted to "Species ranges and patterns of concordance", where the author rightly remarks that there are discontinuous variations in time and space. One of the techniques recommended to biogeographers, in solving problems linked with those variations, is spectral and harmonic analysis. This approach seems quite worthwhile, since it shows that the west of the Rocky Mountains is characterized by rainy winters and, even more sensational, "occasionally this changes seasonally over short distances, as a sharp dividing line between two regimes lying, for example, in Southern Utah and Southern Nevada, near Arizona", which is not very precise from the (bio)geographical point of view. In Chapter 13, the author talks of the future. For him, the two most profitable lines of research will be: "analysis of the eco-physiological basis of species ranges, species nests, etc. and the analysis of population genetic, demographic and spatial processes concerning the dynamics of species ranges". How fortunate that a dynamic bio geographer confirms for us the interest of this dual scientific approach! In conclusion, this book is nevertheless very interesting and can be useful for students. And to finish in the style of the author, I dedicate this amicable review to Pa' and Ma' and I thank my IBM Writing Assistant for the automatic correction of all my spelling mistakes. Dr R. TERCAFS Senior Research Associate of the Belgium National Fund of Scientific Research University of Li#ge Sart Tilman BatTment B 11 B-4000 Liege Belgium