Soils, their formation, properties, composition, and relations to climate and plant growth in the humid and arid regions

CHAPTER XXI.

Chapter 2593 wordsPublic domain

SOILS OF ARID AND HUMID REGIONS CONTINUED, 398.—_Soils of the Tropics_, 398.—Humus in Tropical Soils, 399.—Investigations of Tropical Soils, 401.—_Soils of Samoa and Kamerun_, 402.—Soils of the Samoan Islands, 403.—Soils of Kamerun, 404.—_Soils of Madagascar_, 405.—_Soils of India_, 410.—The Indo-Gangetic Plain, 411.—The Brahmaputra Alluvium in Assam, 413.—Black Soils of Deccan, 414.—Red Soils of the Madras Region, 415.—Laterite Soils, 416.—_Influence of Aridity upon Civilization_, 417.—Preference of Ancient Civilizations for Arid Countries, 417.—Irrigation Necessitates Co-operation, 419.—High and Permanent Productiveness of Arid Soils Induces Permanence of Civil Organization, 419.