Rethink, redesign, reengineer: time is right to rely on biobased systems for sustainable communities.
The challenge is to rethink how the material needs of society can be met by using agricultural-based systems. This rethinking and redesign involves an integration of science and engineering with an emphasis on ecological processes and socioeconomic phenomena.
Typically, the developed world has used a linear approach to utilization and management of resources, according to Donald V Roberts in The Role of Engineering in Sustainable Development, 1994. Natural resources have been extracted without serious consideration of their long-term availability. These resources have been processed into products, which are transported to consumers where all too often their disposal has been without consideration of environmental impact (Figure 1). Unlike ecosystems, we have operated as an "open loop" with no limitations on resources, the ability to produce products, and sources for waste disposal. For far too long, waste disposal has been a primary mode of management, when instead the focus should be on a total resource-recovery approach.
Roberts suggests that we must function like an ecosystem where use, processing, transportation and consumption of resources flow as a "closed loop" with feedback (Figure 2). Throughout the process, wastes are minimized and byproducts are recycled as recovered resources. Energy is minimized by improvements in efficiency and increasingly nonfossil sources should be developed. Engineering design is the crucial piece in this whole process to create innovative processes and products.
Bioprocessing of agricultural materials, including waste biomass, is increasingly a source for bioproducts and energy. Biological processes are a preferred path for processing agricultural-based resources due to higher reaction specificity and fewer toxic byproducts. These characteristics are very consistent with the goal of developing industrial processes and systems, which are environmentally friendly. Increasing the rate and extent of conversion of biological processes is an important step in development of agricultural-based bioindustries.
One innovative potential technology should be investigated as a centerpiece of a total resource-recovery system. Fuel-cell technology can convert biogas directly into electrical and thermal energies for both on-farm uses and to supply community energy needs (Figure 3). This vision of the dairy farm as a system of materials and energy flows offers several opportunities. Agricultural operations (in this case a dairy) expand from just a farm product (milk) to a contemporary system of(l) producing other bioproducts, (2) developing energy which can drive more integrated food and fiber production systems, as well as, (3) generating energy for enterprises on or near the farm or for energy needs of the surrounding community.
Local communities control much of a nation's energy and resource consumption. Therefore, the challenge is to create a sustainable system that integrates energy, environmental, agricultural and industrial innovations. It is out of this context that I proposed the concept of global biologically integrated sustainable communities (GBISC) in the paper "Sustainable communities save energy," published in the March 1992 issue of ASAE's Agricultural Engineering. Worldwide, competition between agriculture and natural resources versus urbanization and industrialization continues to increase. GBISC is equally relevant to the developing and developed communities, although because of infrastructure limitations in developing nations, the concepts of GBISC may, in fact, be stronger drivers in developing communities.
In fact, sustainable agricultural and rural development in these communities is an issue of great urgency and concern. The agricultural sector, more than any other, is critical to economic success because of huge pressures on the natural-resource base in addition to social and institutional stresses. A developing nation's economy is strongly affected by the health of its agricultural sector. Its growth will serve as a stimulus to overall economic progress, whereas a lagging agricultural sector serves as a drain on the economy, shifting resources to food production from other important uses.
Food security is intimately interconnected to environmental practices and policies. A developing nation benefits from participation in world trade in agriculture, but has to ensure its citizens a healthy diet, both in quantity and quality. The objective of the food system is to produce healthy people, not just food. An inclusive and broad based process of agricultural and rural development is the most effective way to reduce poverty.
Two examples of potential sustainable communities can be found in China. I have visited Wusi, near Shanghai and the Guangming Overseas Livestock Farm, close to Shenzhen. In both cases a population of about 10,000-12,000 live in apartment-style housing within a community where 60-70 percent of the people work at an array of 50 to 60 businesses, including numerous agricultural (plant and animal) enterprises within walking or bicycle proximity of work and home.
Making the transition
The Board on Sustainable Development of the National Research Council in its 1999 report, "Our Common Journey: A Transition Toward Sustainability," states, "The primary goals of a transition toward sustainability over the next two generations should be to meet the needs of a much larger but stabilizing human population, to sustain the life support systems of the planet and to substantially reduce hunger and poverty."
The report says the most significant challenges to sustainable development include: lowering fertility to improve the balance between population and resources; increasing opportunities for health and education; providing water, air and sanitation services in urban centers; expanding food production; reducing and reusing materials; using energy more efficiently and implementing conservation measures for living resources.
The future depends on harnessing the power of modern technologies, consistent with the interests of the poor and hungry, and with a respect for the environment.
RELATED ARTICLE: An evolving process rather than a definition
The world is in transition. Picture more people, greater consumption of materials and resources, more connectiveness and a need to reduce poverty without destroying the environment. During the past two decades, "sustainability" has become a principal concept to integrate technological, economic, social and political issues to address environmental protection and economic development.
In 1992, Henry J. Hatch wrote in his article, "Accepting the Challenge of Sustainable Development" in the National Academy of Engineering's The Bridge, that "Sustainable development is the dominant economic, environmental and social issue of the 21st century." It is an idealistic concept, which has its origins in the 1987 report, "Our Common Future," by the United Nation's World Commission on Environment and Development (chaired by Gro Brundtland). In that report, sustainability means, "meeting the needs of the present without compromising the ability of future generations to meet their own needs."
Many have suggested definitions building upon this report. I particularly like Roy F. Weston's description of the concept and impetus for action from his 1993 publication, Sustainable Development: Definition and Implementation Strategies: "Sustainable development is a process of change in which the direction of investment, the orientation of technology, the allocation of resources, and the development and functioning of institutions meet present needs and aspirations without endangering the capacity of natural systems to absorb the effects of human activities, and without compromising the ability of future generations to meet their own needs and aspirations."
Thus, sustainable development is a "process" of redirection, reorientation and reallocation -- an evolving one rather than a definition. As I see it, it is a fundamental redesign of technological, economic and sociological processes to address change.
ASAE Fellow Norman R. Scott is a Professor, Department of Agricultural and Biological Engineering, Cornell University Ithaca, NY. 14853 USA; 607-255-4473, fax 607-255-4080, firstname.lastname@example.org.
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|Author:||Scott, Norman R.|
|Publication:||Resource: Engineering & Technology for a Sustainable World|
|Date:||Sep 1, 2002|
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