To make rational use of natural resources, it is essential to clearly understand the changes occurring in the landscape before our eyes. These changes are the result both of natural processes and of human economic activity. Many natural processes proceed so slowly that, in the plains, the only changes of practical significance over the past several centuries may have been secular fluctuations in climate and the phenomena associated with them. Human economic activity, by contrast, can bring about rapid and profound transformations of the geographical environment. Yet many aspects of humanity's impact on nature remain insufficiently understood, and the practical significance of such activities is often underestimated or even entirely overlooked. This book seeks to reveal the changes that have occurred in the vegetation cover and animal life of the clayey semi-desert region in the northwestern Caspian Lowland over the past two centuries, under the combined influence of human economic activity and long-term fluctuations in humidity. Particular attention is given to processes that arise as by-products of the principal forms of economic activity, since these are most frequently neglected. The book does not examine the direct consequences of various economic activities, nor does it address the specific economic relationships that have contributed to the emergence of anthropogenic features in the landscape of the northwestern Caspian Lowland. Although highly worthy of study, this subject lies far beyond the scope of biological research. The materials on which this book is based consist of the author's field investigations conducted from 1950 to 1956 at the Dzhanibek Research Station of the Institute of Forestry of the Academy of Sciences of the USSR, together with archival and published sources. The names of settlements, rivers, and lakes follow the 1947 administrative map of West Kazakhstan Oblast. During the course of this work, the author received advice and assistance from A. A. Rode, A. G. Gayel, M. N. Polisky, K. S. Khodashova, Yu. A. Isakov, S. D. Erpet, S. N. Kalankina, L. K. Pozdnyakov, V. I. Tsalkin, and P. V. Matyegin, to whom he expresses his sincere gratitude.