Studies on the Cereal Ecosystem
G. R. POTTS and G. P. VICKERMAN
Game Conservancy, Partridge Survival Project, North Farm,
Wmhington, Putborough, West Sussex, England
I. Introduction
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11. The Study Area .
A. Brief History .
B. Crops
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C. Field Size-Hedge Removal and Geographical Concentration of Crops .
D. The Flora of Cereal Fields
E. Foliar Disease, Insect Pests and Cereal Varieties .
A. The Faunal Diversity of Downland, Spring end Winter Barley
B. Faunal Diversity and Undersowing
C. The Relationship Between Faunal and Floral Diversity
D. Dispersal and the Temporary Distribution of Weeds .
A. Composition .
B. Hemiptera
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IU. Changes in Ecological Diversi$y .
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I T . The Invertebrate Fauna of Cereals .
1. Aphids: Introduction
2. Immediate Factors Governing the Peak Density of Aphid Apterae
3. Factors Governing the Rate of Increase of Apterous Aphids
4. The Relationship Between Faunal Diversity and the Number of
6. The Relationship Between Changes in Diversity and Changes in the
6. The Properties of Diversity
7. Parasitism .
1. Introduction
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2. Percentage Composition and Trophic Structure
3. The Distribution of Predatory Diptera
4. The Relationship Between Numbers of Predatory and Non-predatory
in the Cereal Crop
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Apterous Aphids
Numbers of Apterous Aphids
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C. Diptera .
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Diptera
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D. Thysanoptera .
E. Hymenoptera .
1. Introduction
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2. ParasibHost Relationships
3. 8aW9ies
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