Ráðunautafundur - 15.02.1989, Síða 9

-1-
RÁÐUNAUTAFUNDUR 1989
The Evolution of range science and its implications
for grazing management
Frederick D. Provenza
Utah State University, Logan, Utáh 84322-5230
INTRODUCTION
Rangelands are those areas of the world which by reason of physical limitations are
unsuited for cultivation but which provide a source of forage for wild and domestic
herbivores (Stoddart et al„ 1975). Range management is an attempt to optimize the
returns from rangelands in those combinations most desired by and suitable for
society through the manipulation of range ecosystems (Stoddart et al„ 1975). As
such range management is a planning process in which alternative images of a
future possible world are exposed to the decision-maker’s values and the image with
the highest value is selected (Romesburg, 1981). Range science is the body of
scientific knowledge upon which range management is based. Knowledge, the set of
ideas that agree or are consistent with the facts of nature, is discovered through
the application of scientific methods (Romesburg, 1981). Planning and science are
different, but complementary, endeavors. Both are necessary for wise use of range
resources. The purpose of this paper is to discuss (1) the roles of planning and
science as they relate to grazing management, (2) the evolution of range science
and (3) the implications for grazing management.
PLANNING AND SCIENCE
Planning and science are different kinds of decision making (Romesburg, 1981).
Planning exposes alternative images of a future possible world to the decision-
maker’s values, or preferences, and selects the image with the highest value.
Science exposes alternatives theories to facts, selects the theory that agrees most
closely with the facts, and gives it the name law. The essential difference is that
planning uses values as its standard for selection, whereas science uses facts.
Planning
The images in planning are composed of scientific knowledge, common sense, rule-
of-thumb knowledge, untested theories and hunches (Romesburg, 1981). When
planning is imperative, a manager must enter into the planning process with the
best knowledge and thought at hand, regardless of their true value. Planning