Site
Map
 

Ohioline
Ecological
Paradigm
News
Bulletins
Fact Sheets  

Rationale for an Ecology-Based Paradigm

By F. P. Miller
Professor and Director, School of Natural
Resources, and Chairperson, Project Reinvent Vision-Challenge Team on Focus

The fabric of human life is woven on earthen looms it everywhere smells of the clay. Bradley, 1935

Preface

Through Project Reinvent, this College adopted an ecology-based paradigm as the framework for its future. What is meant by this concept? Are we "going green"? Some might wonder if we've come to a philosophical Armageddon between the "nozzleheads" and "treehuggers." Others might question whether we still embrace the concepts of productivity and profitability.

What this College has embraced is not so much a new conceptual framework as it is an extension of the more traditional approach to agricultural production; namely, the recognition that sustainable agriculture must be (1) efficiently productive, (2) economically viable, (3) environmentally compatible, and (4) socially acceptable. We must strive to manage ecosystems and natural resources sustainably. It is these natural resources and associated processes and services (Table 1) that sustain agricultural production and much of the natural resource base that undergirds agriculture and natural resources-based enterprises and uses.

To simply execute a name change and sanction a concept that is, at best, only vaguely understood by many does not automatically make this College "academically correct" to survive a little longer. Nor does the sanctioning of such changes guarantee that this College will be successfully extruded through the ever-narrowing keyhole of public acceptance and support in order to see the early light of the twentyfirst century.

Changing a college name and rallying around a paradigm change without substantive changes in programs and altering our "ways of doing business" are hollow exercises designed for prolonging the status quo and instilling hope for cheap (but probably short-lived) entry to the future. As others have observed, institutional survival is not mandatory witness the fact that two-thirds of the Fortune 500 companies in 1955 no longer exist today. Nor could higher education have survived by offering the same curricula and programs it did forty to fifty years ago.

This College, as identified by its name and defined by its mission and programs, has set its compass on a future prescribed in terms of adding value to biologically derived products and understanding and managing ecosystems through applied ecology, including the human dimensions, as pertains to agriculture in its broadest sense.

By adopting an ecology-based paradigm, this College recognizes, as did Aldo Leopold, that agriculture and natural resources management should encompass more than the relentless race between emergence of new pests and environmental stresses and the development of technologies for their suppression and control. The students of this College must recognize the relationship between ecological impairment or natural resource mismanagement and the decline of economic and social well-being as manifested by poverty throughout the world.

The Linkage of People's Well-Being to Natural Resources

The desire of all human beings is to "live well." While the definition of "living well" varies with individuals and cultures, it is irrefutable that the sustenance and well-being of people everywhere are inextricably linked to the earth's natural resource base.

One of the defining social themes of this decade has been ecological awareness. As a consequence of this public consciousness, Gallagher et al. (1995) assert that ecology1 now stands at the interface between science and public policy. Basic ecology coupled with human needs and desires results in applied ecology which includes agriculture2, grassland-range management, forestland management/ forestry, wildlife-fisheries management, and other kinds of natural resources management (Cohen, 1995).

Natural landscapes and ecosystems, once populated, converted to and managed for other uses, become cultural landscapes and ecosystems. If we and our natural resources-dependent societies are to be sustained at an acceptable level of well-being through our endowment of natural resources, then we must properly manage this natural resource base. Furthermore, we must understand the ecological ,"machinery" or processes that govern the quality, resilience, and assimilation capacity of the ecosystems we occupy. To strive for sustainable lifestyles or sustainable development without a concurrent commitment to understanding and properly managing ecosystems and ecological processes is simply not possible.

Managing Ecosystems and Their Machinery: An Analogy

The essence of agriculture is (1) the capture of solar energy through primary production (photosynthesis) and (2) management of nutrient stocks and stresses. Farmers, foresters, and wildlife-fisheries managers all manage ecosystems. They all manage these ecosystems and their biological productivity for different reasons-corn for cows; turf for golf courses or lawns; forests for fiber, wildlife habitat and/or recreation; plants for landscaping; and fish via aquaculture for niche markets. Other ecosystems are managed for their aesthetic value or spiritual appeal.

These farmers and natural resource managers must pay attention to nutrient cycles through fertility management; the hydrologic cycle through managing runoff, infiltration, controlling erosion, and protecting water quality; biological diversity and habitat quality by relying on indigenous species to control diseases and insects, or using other practices, including genetic selection and chemistry to suppress and control weeds, disease, and insects; and the assimilation capacity of the ecosystems to accommodate wastes and residues. These landscape or ecosystem managers strive to maintain the integrity of ecological processes that undergird and sustain biological productivity.

Adverse responses to ecosystem mismanagement include soil compaction and poor soil tilth, excessive runoff and soil erosion, reduced infiltration, organic matter breakdown, fertility imbalances, diseased-weakened plants and animals, water quality impairment, reduced biological productivity and vigor, and ultimately loss of the ecosystem's capacity to sustain productivity. Thus, the key to sustainability is the recognition of an ecosystem's capacity to accommodate various uses and maintenance of those ecological processes and services that undergird the natural resource base upon which biological productivity depends. Table 1 summarizes these ecosystem processes, "goods" and "services."

These ecological processes and services are the "machinery" that drives and sustains agriculture and natural resource-related industries. These ecological processes can be likened to the "machinery" in a factory. Unless this "machinery" is maintained, the production output from the factory is at risk and product quality is impaired. Figure 1 illustrates this factory analogy as compared to an agricultural enterprise.

While such an analogy is obvious, there is a crucial difference between an automobile factory and a farm. The auto factory relies on a sequence of specific functions using machines and mostly nonrenewable resources. The physics and engineering principles employed in the design, operation, and maintenance of these machines in the auto factory are well understood. But as Vandermeer (1992) emphasizes, the agricultural (or forestry, fishery, etc.) analog of the factory analogy "does not consist of known machines; rather it consists of all of the complex and diverse rules of ecology. These rules are not yet well known to science, yet they are, in principle, the 'machines' inside the factory of agricultural production," once again emphasizing the point that agriculture, forestry, and other renewable natural resource-based activities are driven, regulated, and sustained by the "machinery" of ecological processes.

The Essence of an Ecology-Based Paradigm

The essence of an ecology-based paradigm for sustainably managing agricultural and natural resources- dependent systems is the recognition and maintenance of those ecological processes as set forth in Table 1. While very high levels of biological productivity can be wrestled from the earth through intensive resource inputs (e.g. fertilizers, pesticides, equipment) and management, the long-term sustainability of biological production will ultimately be regulated by those ecological processes that govern an ecosystem's capacity to produce. The Ecological Society of America (1995) articulated this concept as follows:

"... strategies to provide ecosystem goods and services cannot take as their starting points mandated yield goals, timber supply, water demand, or arbitrarily set harvests offish-instead, sustainability must be the primary objective, levels of commodity and amenity must be adjusted to meet that goal."

The new paradigm for agriculture and management of natural resources should rest solidly upon the foundation of those ecological principles and processes that ultimately drive and sustain the ability and capacity of ecosystems to support agricultural production and renewable natural resources management systems.

As land and ecosystems accommodate more people and their demands for affluence as well as more intensive agricultural and natural resources management systems, the more intrusive people become on the natural resource base and those processes that sustain this base. At what point does human culture and its demands on the natural resource base, including its assimilation capacity, become excessive, i.e., unsustainable? It is incumbent upon today's colleges of agriculture and natural resources/environmental sciences to design their academic, research, and outreach-extension programs to address these questions within the framework of an ecology- based paradigm.

Distilled to its simplest form, an ecology-based paradigm for ecosystem management constitutes working within the limits of the ecosystem in order to maintain ecological sustainability (Dombeck, 1995). For example, rather than focusing exclusively on maximizing agricultural production, as is the case for traditional "corn clubs" and other production contests, the ecological management focus ought to select "winners" on the basis of resource and energy investment efficiencies, as well as production and economics. Furthermore, production contest winners also should be judged on the basis of how well they control environmental leakages of their production inputs and how well they sustain the natural resource base and ecological processes.

Economic and policy incentives often (usually) drive natural resources management decisions that may not be biologically sustainable. And some ecosystems must be converted to non-biological uses for the benefit and well- being of society. But our obligation as a college should to be point out that biological sustenance is predicated on the maintenance of those ecological processes that sustain and undergird agriculture and natural resources-based industries and activities.

Human Dimension of Environmental Change

Global Perspective: While natural phenomena such as glaciation, volcanic activity, earthquakes, tectonic forces, and climate changes over geologic time have convulsed the earth and caused major changes, Vitousek et al. (1996) state that our human species is now the premier agent of ecological disturbance on the planet. In both "developed" and "developing" societies, agriculture and related natural resource-based industries and activities are the most extensive users of land and transformers of the environment (Ausubel, 1996).

Indeed, the human disturbance of the earth and its natural processes (Table 1) has been both swift and significant, especially over the last three centuries. Since 1700, the world's forests and woodlands have diminished by about 20 percent or nearly 3 billion acres. Similarly, grasslands and pasture have declined by 1.4 billion acres. During this same time frame, i.e., since the year 1700, land converted to cultivation increased about 3 billion acres, an increase of 466 percent in less than three centuries (Richards, 1990).

U.S. Perspective: The North American continent was swept by such changes in an even shorter period of time as the westward migration reached its zenith during the latter half of the nineteenth century. Hundreds of millions of acres of forests and prairies were cleared, plowed, and/or overgrazed. U.S. cropland increased 16 fold, from 20 million acres to 319 million acres, between 1800 and 1900 with pasture and hayland increases at least equal to these figures. From 1850 to 1910, U.S. forests were being cleared for cropland and pastureland at the unprecedented rate of 13.5 square miles (approximately 8,700 acres) per day for 60 years (MacCleery, 1995).

State Perspective: Ohio's human habitation has likewise resulted in dramatic changes to its ecology and natural resource base. It has been estimated (Pimentel, 1989) that Ohio's native hunting-gathering population required about 400 to 600 acres to adequately sustain one person. In what is now the area encompassed in Ohio's boundaries, the state's natural resources could sustain a hunting-gathering population of about 50,000 people. Today, there are 220 times that many people (11 million) residing in Ohio. Much of the state's original mixed deciduous forests and isolated wetland prairies have given way to about 14.5 million acres of cropland and pasture, cities and suburbs, parks, roads, reservoirs, and airports. The apex of land in farms and number of farms in Ohio occurred in the 1930s.

With the advent of technological improvements in agriculture and the state's expanding urban oriented population, the number of farms and crop land-pasture land has been decreasing since the 1930s. And yet, the combination of Ohio's natural resource base and technology has resulted in seven times as much corn and nearly three times as many soybeans being produced today than in 1950 from 135,000 fewer farms. Ohio is currently losing the equivalent of about 40 farms and about 2,000 acres per week from its farmland base as land is converted to other uses to accommodate the needs and desires (e.g. parks, recreation areas) of its population.

Ecosystem Response to Changes in Land Use and Management

These major changes in plant cover and land use resulting from human habitation and development have had profound impacts on ecosystem behavior and response to the hydrologic cycle and other ecological processes and services (Table 1). Figure 2 provides an example of how an ecosystem [watershed in this case) responds to changes in land use and management. Sediment is used in this example as the indicator of watershed response to these changes. Other response measures such as nitrogen, phosphorus, bacteria, biochemical oxidation demand (BOD), and pesticide residues also could be used. Each watershed or ecosystem will have a characteristic response "signature" as land use and management changes occur over time. These responses or environmental impacts will vary with the character of the ecosystem (e.g. soil type, topography, weather patterns, geologic substrata, vegetation) and amount of disturbance or changes in use.

An ecology-based management strategy for agriculture, forestry, and other natural resource related uses is to recognize the ramifications of these responses and implement strategies and practices to suppress or control these impacts. Practices like no tillage, minimum tillage, residue management, grass waterways, riparian protection, precision fertility chemical management, genetic selection for disease insect resistance, water management such as via diversions, berms, contour planting, etc., all contribute toward modifying the ecosystem response signature, thus, minimizing environmental impacts.

The Principles of Ecology and Management of Ecosystems

Ecosystems, whether defined as a corn field, herd of cattle, watershed, farm, forest, wetland, lake, or urban community, are dynamic systems governed by a myriad of complex processes ranging from biological competition, metabolism, and photosynthesis to the hydrologic and nitrogen cycles. At the heart of ecosystem dynamics within these ecosystems are the processes of energy flow and biogeochemical cycling. As stated previously, agriculture and the management of renewable natural resources involve the capture of solar energy through biomass, the manipulation of nutrients, and management interventions to alleviate ecosystem stresses such as those imposed by pests and water (either too much or too little). Following from these ecological processes and the limitations on managing ecosystems, several principles of ecology can be stated as follows:

• "You can't do merely just one thing-all ecosystems leak", i.e., everything is connected to everything else, thus, every manipulation of an ecosystem has both intended and unintended consequences, for example, see Figure 2.
• "There is no free lunch"; another way of expressing the second law of thermodynamics; i.e., energy, effort, and resources invested in manipulating and managing ecosystems always result in less than 100 percent efficiency, thus, energy (e.g. heat) and waste by-products (e.g. manure, residue) end up being dissipated to and/or concentrated in the environment.
• "There is no 'away' "; another way of expressing the law of conservation of matter, i.e., everything has to go somewhere, thus, we cannot throw anything 'away' without it showing up somewhere else.
• "You cannot do everything equally everywhere", i.e., landscapes and other ecosystems (e.g. atmosphere, oceans) vary in their capability and capacity to grow corn and assimilate wastes as well as their stability (e.g. vulnerability to earthquakes, volcanic action, erosivity, expansive clays) and response to the hydrologic cycle (e.g. flood plains vs. upland vs. coastal lowlands) and gaseous emissions. The world's insurance industry is beginning to understand this principle through very expensive "lessons," with damage from natural disasters totaling an estimated one billion dollars per week in the U.S. alone (Baker, 1997).
• "Nature has no ethic or preferred status, " i.e., ecosystems will adapt to conditions imposed upon them whether or not these conditions (e.g. polluted or septic lake, degraded land, atmospheric change, predator-prey dynamics) are desired by humans.

Through our human experience, we and our institutions such as agriculture, natural resource based industries, insurance industry, banking industry and others, have had to deal with these principles in managing resources for individual gain as well as for the social good. While our knowledge is incomplete, farmers, foresters, fisheries, and wildlife managers have experience in managing ecosystems under these principles, recognizing the limits and vulnerability of certain ecosystems to sustain high yields and "leak" their production resources (e.g., nutrients, pesticides, manure, sediment) to other ecosystems. Likewise, developers, land planners, and civic officials recognize the different capabilities of various landscapes to accommodate foundation loads and assimilate wastes as well as the vulnerability of certain ecosystems to flooding, hurricane damage, landslides, or earthquake damage. The insurance industry has seen claims for weather-related disasters in the U.S. rise from sixteen billion dollars for the entire decade of the 1980s to approximately fifty billion dollars for only the first half of the 1990s (Flavin, 1996). And uninsured weather-related losses are even greater, as are losses from nonweather-related damage to property.

Lending institutions and the banking industry have begun to recognize (Peirce, 1995) their role in exacerbating poorly planned developments that have repercussions on both the environment and quality of life, as well as increasing the costs (taxes) to service these ill-planned land uses. Local jurisdictions have begun to understand that agriculture more than pays its way in taxes because it requires fewer tax supported services. Urban-suburban housing developments, on the other hand, seldom pay their way in taxes, thereby requiring general tax increases to cover the costs of servicing these urban-suburban communities. Thus, the implications and costs of ecosystem management transcend the domain of agriculture.

Defining Our Domain

Rural America, like the rest of society, has undergone major changes. These changes are a result of the infusion of science and technology in agriculture and its allied industries, coupled with dramatic changes in everything from transportation to franchise marketing. These social and technological changes should be within the domain of our College's attention. As the Industrial Revolution and later the scientific and information revolutions swept over much of rural America, significant, even convulsive, changes occurred. Since World War 11, plant breeders, agronomists, agricultural engineers, animal scientists, pathologists, entomologists, and others have wrought the wonders of a virtual cornucopia out of the natural resource base of rural America.

But this science and technology-induced cornucopia has also wrought unintended environmental and social impacts. Production resources have leaked into other ecosystems such as groundwater, streams, and lakes. These "technological exhausts" are now being accounted for and new technologies and strategies have been and are being developed to minimize or eliminate these "externalities." Aside from social scientists and a few others, the production-oriented scientists did not concern themselves greatly with the repercussions of the human dimensions of the adoption of science and technology by agriculture and other natural resources-dependent industries. The depopulation on of rural America through the industrial-science revolution, the reduction in number of farms and farmland, and the influx of many of these former farmers and rural residents to the cities were unintended consequences of adopting science and technology in agriculture.

It should not be this College's purpose or objective to judge whether such changes are good or bad. Nor should the College's objective be to advocate or promote the "saving" of farmland, forests, wetlands, or the "family farm." However, it should be within this College's scope of interests to define the nature of such dynamics so that Ohio's citizens and land-natural resources decision-makers will understand the environmental, social, and economic repercussions, trade-offs, and costs of their actions and policies.

Considering these technological, ecological, and social forces, one concludes that the future well being and sustainability of Ohio's agriculture and natural resources-based enterprises and activities will depend largely on (1) our ability to maintain the productivity and quality of the state's natural resource base, (2) the assimilation capacity of this resource base, (3) maintaining the integrity of those ecological processes necessary to sustain the state's renewable natural resource-based industries and activities, and (4) the social acceptance of specific enterprises, management systems, and related technologies. There are many instances in Ohio where agriculture has exceeded the assimilation capacity (e.g. manure loading) and/or where certain technologies or production systems have been rejected by society.

What Should We Expect from Students in this College?

In addition to "agricultural," the words "food" and "environmental sciences" have been added to the College's name. These additions, coupled with the adoption of an ecology-based paradigm, signal significant broadening and integration of the College's domain which must be reflected through its curricula and programs. It seems appropriate, therefore, to reflect on what common ground its curricula and programs should be built. While it might seem obvious to those with an ecology and natural resources management background to suggest a litany of questions and issues that today's students, regardless of their major or interests, should be exposed to and be articulate about, the fact is that many, if not most, of our students in this College are not able to confidently address such questions and issues. For example:

• Should our students be aware of what impacts and marketing changes are occurring in agriculture with the emphasis on value-added products rather than traditional bulk commodities?
• Should our College's graduates be able to articulate why we have nitrate alerts about our drinking water and eutrophication episodes? Can they relate these events to geochemical cycling, solute chemistry, and the assimilation capacity of our environment with respect to how much fertilizer, animal manure, municipal-industrial sludge, individual on-site waste (septic) systems, and other nutrient sources can be accommodated?
• Should our students be able to articulate about the human dimensions as well as the environmental impacts of the infusion of technology and other forces on Ohio's agriculture, considering that there are 135,000 fewer Ohio farms today than in 1950 even though total production of corn and soybeans is 2.8 and 7-fold greater, respectively? And can these students discuss why the character of Ohio's rural communities as well as its wildlife have changed simultaneously during this period?
• Can our students articulate about the impact technology has had on land use as reflected in greater production per unit of land, thereby precluding the necessity to convert other lands to cropland and "saving" these "other lands" or various uses?
• What conflict resolution protocols do our students utilize to resolve management decisions between those who value a forest or wetland for its timber and development versus those who value the forest or wetland for its wildlife, aesthetic appeal, or ecological functions?
• What background do our students have with respect to developing an argument about whether modern agriculture, forestry, and/or fisheries management is thermodynamically efficient or positive (captures more solar energy than is used to subsidize it through fossil fuel-equivalents) and whether it is thermodynamically and/or ecologically sustainable?

Requisites of Sustainable Ecology-Based Agriculture

Students in this College, regardless of major or specialty, should have a common conceptual base specific to the interests and focus of this College upon which to build a major, just as English, Chemistry, and Math are common baseline requirements. As part of this foundation, the following conceptual matrix is offered as an example.

Starting with the basics of agriculture, i.e., the capture of solar energy and management of nutrient stocks and stresses, there are certain requisites that appear common to almost every agricultural system, whether it is an integrated, industrialized enterprise, an organic farm, a hydroponic system, or a primitive slash and burn or subsistence type operation.

Choosing a Production System

The types of production systems are chosen for a variety of reasons. Some farmers choose animal-based systems, others opt for cash grain or niche market enterprises. What drives these decisions ranges from cultural values and market availability to resource availability and personal lifestyle choices. Some farmers prefer to be dairy farmers. Others prefer to work off the farm and operate their farms in other ways. Thus, the types of fanning are determined by many factors and forces, ranging from economics to lifestyle choices. There is no single system that is best.

Natural Resource Requisites

To have a viable and productive agriculture, certain natural resources requisites must be available. These include soil resources, adequate water provided through either rainfall or irrigation or both, topography that is amenable to cultivation and crop production, and adequate climatic conditions.

Maintenance of Ecological Processes

Another requisite for sustainable agriculture is the necessity to maintain those ecological processes that undergird the soil, water, and natural resource base for biomass production. Farmers must manage their soils so that erosion, compaction, and organic matter loss do not occur. They must manage the soil's nutrient stocks to maintain the appropriate nutrient balance by adjusting pH through liming and adding nutrients through fertilizers, animal and/or green manures, legumes, and other means.

Production System Requisites

All farmers, regardless of the type of production system, must address certain production requisites common to all systems. These requisites include germplasm selection (i.e., kind of crop and cultivar, type of animal and genetics), seed-soil contact, nutrient management, water management, weed and disease insect suppression and control, harvesting system, and residue management.

Regardless of the type of production system, these requisites must be met. Organic farmers meet these requisites one way, commercial farmers another, and subsistence farmers address these requisites in still different ways. The latter may use a crude jab stick to plant seed and get soil-seed contact. A commercial farmer may use a modem planter to do the same job. The commercial farmer may use fertilizer to manage nutrients, whereas a slash and bum fanner may rely on indigenous fertility for a short period and move on. Each requisite will be addressed in different ways. Similarly, post-harvest systems will vary as will marketing agricultural commodities and adding value to them.

Metrics of Sustainable Ecology-Based Agriculture

Table 2 summarizes these production requisites and provides a matrix approach to considering the "measures" or "metrics" by which each requisite might be assessed or measured. Table 3 provides an example of how various production systems might be compared or measured against each other.

Certainly, productivity and economic returns or profitability are obvious metrics of any system. But other measures of these production requisites (Table 2) and systems (Table 3) can be identified and assessed. For example, does a modern, commercial farm require more energy to produce 200 bushels of corn than an organic, Amish, or hydroponic system? Is more solar energy captured than is invested in these systems? And what about risk aversion, environmental impacts, wear and tear on the soil resource, and stress on ecosystem processes? How much "leakage" occurs from each system with respect to water quality impacts, erosion, and carbon dioxide losses or sequestration? What are the implications on land requirements and labor for each system? And what about the social acceptance and/ or amenity values (e.g., air quality-odor, aesthetic appeal, etc.)?

The point to be emphasized is that students in this College should have some elementary understanding of these concepts and metrics. There is no single, optimal system. Each system can be managed so that it is productive, economically viable, environmentally compatible, and socially acceptable. Thus, the metrics of production and natural resources management systems go far beyond simply production output and income generation. These metrics must include the whole of the ecosystem, including the human dimension, in which agriculture is practiced and natural resources are managed.

Commitment to an Ecology-Based Paradigm

In order to address ecosystem quality and sustainability, twenty-first century colleges of agriculture and natural resources/environmental sciences must be more integrated, comprehensive, and holistic than in the past. They must encompass the sciences and resource management strategies as well as the human dimensions of the whole ecosystem. Certainly, reductionist research has contributed much to modern science. As McHarg (1997) has stated, however, reductionism need not be superseded, but certainly it must be augmented to include synthesis and holism. We must be reminded that, regardless of how we balance the reductionist-integrated research and management equation, human beings are components of ecosystems. Therefore, we must learn how to function within the sustainable dimensions of ecosystems if both human well-being and ecosystem processes are to be sustained.

Regardless of the kind of paradigm this College adopts, the relationship of people with their environment and natural resource base will ultimately determine the individual's and society's well-being and whether this well-being can be sustained. It seems appropriate, therefore, that this College's future wellbeing is, likewise, predicated on those forces and processes that will determine the health and sustenance of the ecosystems upon which the future of agriculture and natural resources management rest.

References

Ausubel, J. H. 1996. Can technology spare the earth? Amer. Scientist 84:166-178.

Baker, D. J. 1997. Presidential initiatives and the geosciences. Geotimes 42(4):5.

Bradley, J. H. 1935. Autobiography of earth. New York: Coward-McCann, Inc. p. 331.

Cohen, J. E. 1995. How many people can the earth support? New York: W. W. Norton Co., Inc.

Dombeck, M. P. 1995. From commodity to community: A common sense approach to understanding ecosystem management. Distinguished Lecture Series 111. Oct. 17, 1995. The Pennsylvania State University, School of Forest Resources. p. 16.

Ehrlich, P. R. and A. H. Ehrlich. 1991. Healing the planet: Strategies for resolving the environmental crisis. Reading, Mass.: Addison-Wesley Publishing Co.

Flavin, C. 1996. Insurance industry reels. Vital Signs, 1996 (L. R. Brown, C. Flavin, H. Kane). Washington, D.C.: Worldwatch Institute. p. 118.

Gallagher, R. B., J. Fischman, P. J. Hines. 1995. Big questions for a small planet. Science 269:283.

Lubchenco, J., P. G. Risser, A. C. Janetos, J. R. Gosz, B. D. Gold, and M. M. Holland. 1993. Priorities for an environmental science agenda for the Clinton-Gore Administration: Recommendations for transition planning. Bulletin of the Ecological Society of America 74:4-8.

MacCleery, D. 1995. Resiliency: The trademark of American forests. Forest Products Jour. 45(l):18-28.

McHarg, 1. L. 1997. Natural factors in planning. Jour. Soil and Water Conservation 52(l):13-17.

Peirce, N. R. 1995. A megabank speaks out on sprawl. National Journal Vol. 27 (11): (March 18, 1995). p. 699.

Pimentel, D. 1989. Ecological systems, natural resources, and food supplies. In D. Pimentel and C. W. Hall, eds. Food and Natural Resources. San Diego: Academic Press, Inc. pp. 1-29.

Richards, J. F. 1990. Land transformations. In B. L. Turner 11, W. C. Clark, R. W. Kates, J. F. Richards, J. T. Mathews, and W. B. Meyer, eds. The earth as transformed by human action. New York: Cambridge University Press. pp. 163- 178.

Richardson, C. J. 1994. Ecological functions and human values in wetlands: A framework for assessing forestry impacts. Wetlands 14:1-9.

The scientific basis for ecosystem management. 1995. Ad Hoc Committee Report, Ecological Society of America Newsletter (N. Cavender, ed.) No. 44, Dec., 1995: p. 1.

Vandermeer, J. H. 1992. Thoughts on agriculture and the environment in a post-modern world. Symposium on Enhancing the Future of the Land Grant System. National Academy of Sciences. Board on Agriculture. Irving, Calif. April 3-4, 1992. p. 14.

Vitousek, P. M., C. M. DAntonio, L. L. Loope, and R. Westbrooks. 1996. Biological invasions as global environmental change. Amer. Scientist 84:468-478.

Wolman, M. G. 1967. A cycle of sedimentation and erosion in urban river channels. Geogr. Ann. 49A:385-395.

1Ecology concerns itself with the interrelationships of living organisms, including plants and animals as well as humans, and their environments.

2Agriculture is used herein in the broadest sense, encompassing and expanding on the definition offered by the National Academy of Science: "the entire system that manages natural and altered ecosystems for growing, processing, and providing food, fiber, biomass, and amenity value (e.g., recreation) for the globe. It includes: the management of natural resources such as soil, surface and groundwater, forests, grasslands- rangelands, and other lands for commercial or recreational uses, and wildlife; the social, physical, and biological environments; and the public policy issues that relate to the system. All activities, practices, and processes of the public and private sectors involved in agriculture and forestry are contained within the system."