X Contents 



Build-Up of the Substratum 69 



Rock, Sand, and Soil in Terrestrial Environment 71 



Influence of the Land Substrata 71 



Land Surfaces and Animals 72 



Soil in Its Action on Plants 73 



Action of Organisms on Soil 76 



Abundance of Organisms in Soil 76 



Soil Formation 77 



Humus and the Colloidal Complex 79 



The Soil Profile 80 



Soil-group Divisions 84 



Chapter 4 ■ WATER 90 



Water Problem in the Aquatic Environment 91 



Composition of Natural Waters 91 



Methods of Meeting Osmotic Problem 95 



Limiting Effects of Salinity 97 



Amphibious Situations 99 



Swamps and Temporary Pools 99 



Tidal Zone 101 



Water Problem in the Terrestrial Environment 107 



Occurrence of Water in Land Environment 109 



Moisture in the Soil Ill 



Moisture in the Air 112 



Microclimates 117 



Meeting Water Problem on Land 119 



Influence of Moisture on Growth and Distribution 121 



Chapter 5 • TEMPERATURE 129 



Distribution of Temperature 129 



Extremes of Temperature and of Tolerance 129 



Changes in Temperature 131 



Changes in Time 131 



Horizontal Changes 134 



Vertical Changes 134 



Seasonal Changes in Vertical Temperature Structure .... 138 



Biological Action of Temperature 141 



Extreme Temperature 142 



Minimum Temperatures 142 



Maximum Temperatures 143 



Methods of Meeting Temperature Extremes 144 



Morphological and Physiological Adaptations 144 



Thermal Migrations 148 



Action within Effective Range 152 



Effect of Temperature on Biological Rates 152 



Optimum Temperature 155 



Other Effects of Temperature 156 



Action of Temperature on Distribution 159 



Mode of Temperature Limitation 159 



Control by Extremes 160 



