8153

• UCREFRP Catalog Number: 8153
• Author: Jacobs, e. L. W.
• Title: Editor
• USFW Year: Series
• USFW - Doc Type: 1989
• Copyright Material: YES

FOREWORD
Selenium is recognized as an essential element for animals but not for plants.
The Astragalus species has been a known Se accumulator for more than 50 years.
However, more recent research has shown that Se may be absorbed by other plant
species in amounts that may be toxic to animals, depending on soil and plant factors.
The development of irrigated agriculture in the western San Joaquin Valley in
California has changed the drainage patterns, apparently increasing the mobility of
Se from geologic deposits. Adverse effects on the wildlife in this area have been re-
ported in the past 8 years on the Kesterson Reservoir at the Kesterson National Wild-
life Refuge. As a result, significant research efforts have been aimed at determining
the cause-effect relationships and methods of managing this problem.
Selenium in Agriculture and the Environment is an up-to-date review of the
geochemistry, chemical reactions, and factors affecting the bioavailability of Se in
various ecosystems. In addition, this publication contains information on recent Se
research on soils and groundwaters of the San Joaquin Valley. Such information
should help clarify some of the relationships of Se in the biosphere and stimulate
further research to determine improved management techniques to minimize adverse
effects of Se in the environment.
The American Society of Agronomy and the Soil Science Society of America
are pleased to have sponsored the symposium "Selenium in Irrigated Agriculture"
at the 1986 Annual Meeting on 2 Dec. 1986 and this publication that has resulted
from the symposium.
On behalf of the American Society of Agronomy and the Soil Science Society
of America, we thank the authors, editors, and members of the organizing committee.
J.J. MORTVEDT, president
Soil Science Society of America
E.C.A. RUNGE, president
American Society of Agronomy
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