|Biological Control Bookshelf|
Arthropod Natural Enemies in Arable Land I: Density, Spatial Heterogeneity and Dispersal
This book is the first of three volumes that will form the proceedings of a series of European workshops that deal with several aspects of arthropod predator and parasitioid ecology. The first EC-workshop, Estimating Population Densities and Dispersal Rates of Beneficial Predators and Parasitoids in Agroecosystems, took place in Aarhus, Denmark in October 1993. This 314-page book contains 24 highly technical scientific papers and 2 discussion papers, all of which are probably beyond the interest of the average reader interested in implementing biological control. Geared toward the basic research scientist, the papers discuss how various methods (pitfall traps, suction devices, mark-release-recapture, etc.) were used to estimate population densities, or examine spatial distribution, or monitor dispersal of spiders, ground beetles, and other beneficial arthropods in different crops. The first discussion paper reviews the principle sampling methods available for ecological studies, providing the relative advantages and disadvantages and limitations of each, but concludes that information on the efficiency of these methods is sparse. The second, much shorter discussion paper concludes that within-field spatial heterogeneity is probably important to understanding natural enemy ecology and developing IPM strategies involving natural enemy conservation, but we don't know a whole lot about it, and more investigation needs to be done-using the useful methodologies described.
Arthropod Natural Enemies in Arable Land II: Survival, Reproduction and Enhancement
Second in the series, this book details the proceedings of the workshop in The Netherlands in 1994: Estimating Survival and Reproduction of Beneficial Predators and Parasitoids in Relation to Food Availablility and Quality of the Habitat. In this book there is one discussion paper for each of the three main topics (survival, reproduction, and enhancement) in addition to several scientific treatises. The discussion paper on survival mentions experimental approaches to estimating survival, and then discusses how several categories of mortality factors impact populations. Understanding which key factors can be managed will help increase beneficials' survival. Reproduction of natural enemies is discussed in relation to habitat quality and food availability. Strategies of within- and between-field habitat diversification are likely to be the main approaches for increasing natural enemy reproduction, and promoting biological control. The paper on agricultural practices which enhance numbers of beneficial arthropods is a summary of the main discussion topics held during the workshop and is not intended to be a comprehensive review of the subject. They talked about system approaches, applied nature conservation, habitat structure in relation to the distribution of natural enemies, and even how "beneficial" predators really are? (in terms of pest regulation). Their conclusions were that most attempts to increase the diversity of agroecosystems resulted in more questions than answers about the role of natural enemies.so as always, more studies are necessary.
Arthropod Natural Enemies in Arable Land III
The final book in this series will cover the proceedings of a third conference held in Bristol, England in 1995, with the topic Analysing and Modelling of Population Dynamics of Beneficial Predators and Parasitoids in Agroecosystems.
These books are available in North America ($27 per book) only from
David Brown Book Company
P.O. Box 511
Oakville, CT 06779
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