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Harry Janes, James Cavazzoni, Guna Alagappan, David Specca, and Joseph Willis

A qualitative systems approach to controlled environment agriculture (CEA) is presented by means of several multi-institutional projects integrated into a demonstration greenhouse at the Burlington County Resource Recovery Complex (BCRRC), N.J. The greenhouse has about 0.4 ha of production space, and is located about 800 m from the about 40-ha BCRRC landfill site. A portion of the landfill gas produced from the BCRRC site is used for microturbine electricity generation and for heating the greenhouse. The waste heat from the turbines, which are roughly 15 m from the greenhouse, is used as the main heat source for the greenhouse in the winter months, and to desalinate water when heating is not required. Recovery of this waste heat increases the energy efficiency of the four 30-kW turbines from about 25% to 75%. Within the greenhouse, aquaculture and hydroponic crop production are coupled by recycling the aquaculture effluent as a nutrient source for the plants. Both the sludge resulting from the filtered effluent and the inedible biomass from harvested plants are vermicomposted (i.e., rather than being sent to the landfill), resulting in marketable products such as soil amendments and liquid plant fertilizer. If suitably cleaned of contaminants, the CO2 from the landfill gas may be used to enrich the plant growing area within the greenhouse to increase the yield of the edible products. Landfill gas from the BCRRC site has successfully been processed to recover liquid commercial grade CO2 and contaminant-free methane-CO2, with the potential for this gas mixture to be applied as a feedstock for fuel cells or for methanol production. Carbon dioxide from the turbine exhaust may also be recovered for greenhouse enrichment. Alternatively, algal culture may be used to assimilate CO2 from the turbine exhaust into biomass, which may then be used as a biofuel, or possibly as fish feed, thus making the system more self-contained. By recycling energy and materials, the system described would displace fossil fuel use, mitigating negative environmental impacts such as greenhouse gas emissions, and generate less waste in need of disposal. Successful implementation of the coupled landfill (gas-to-energy · aquaponic · desalination) system would particularly benefit developing regions, such as those of the Greater Caribbean Basin.

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Abstract

Asparagus plantings in the Bajio area of Mexico were managed to provide 2 harvest periods, i.e., 2 vegetative periods and 1 dormant period per year. Cumulative yields for a 5-year period were substantially higher from the plots harvested twice annually than those from a conventional spring harvest schedule.

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Jesús A. Gil-Ribes, Louise Ferguson, Sergio Castro-Garcia, and Gregorio L. Blanco-Rodán

organizations is needed. The cooperating researchers are engineers, horticulturists, food technologists, agricultural economists, producers, workers, and their representatives. The academic engineer actively participates in both the development and education

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M.S. Schroeder, N.G. Creamer, H.M Linker, J.P. Mueller, and P. Rzewnicki

There is an increasing demand for education in organic and sustainable agriculture from undergraduates, graduate students and extension agents. In this paper, we discuss highlights and evaluations of a multilevel approach to education currently being developed at North Carolina State University (NCSU) that integrates interdisciplinary training in organic and sustainable agriculture and the related discipline of agroecology through a variety of programs for undergraduate students, graduate students, and extension agents. These educational programs are possible because of a committed interdisciplinary faculty team and the Center for Environmental Farming Systems, a facility dedicated to sustainable and organic agriculture research, education, and outreach. Undergraduate programs include an inquiry-based sustainable agriculture summer internship program, a sustainable agriculture apprenticeship program, and an interdisciplinary agroecology minor that includes two newly developed courses in agroecology and a web-based agroecology course. Research projects and a diversity of courses focusing on aspects of sustainable and organic agriculture are available at NCSU for graduate students and a PhD sustainable agriculture minor is under development. A series of workshops on organic systems training offered as a graduate-level course at NCSU for extension agents is also described. Connecting experiential training to a strong interdisciplinary academic curriculum in organic and sustainable agriculture was a primary objective and a common element across all programs. We believe the NCSU educational approach and programs described here may offer insights for other land grant universities considering developing multilevel sustainable agriculture educational programs.

Open access

Spark M. Matsunaga

Abstract

The theme that I am going to address, “Meeting the World Food Crisis through American Tropical Agricultural Research,” involves two basic assumptions:

First, there is, or there will be a world food crisis.

Second, that crisis can, at least in part, be met through American Tropical Agricultural Research

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Edward P. Glenn

The delta of the Colorado River in Mexico historically contained 780,000 ha of riparian, marsh, and gallery forest habitat. Similar to other desert river deltas, such as the Nile and Indus, the lower delta of the Colorado River has been severely affected by the upstream diversion of water for human use. However, several large marsh areas of conservation interest still occur below the agricultural fields in Mexico. They are supported by flood water, agricultural drainage water, and municipal sewage effluent, as well as by seawater in the intertidal zone. The main anthropogenic marshes are the Rio Hardy wetland, maintained by geothermal discharge and Mexicali irrigation return flows in the western delta, and Cienega de Santa Clara, maintained by local irrigation return flows and by discharge of Wellton-Mohowk Valley drainage from the United States, imported via a 80-km canal to Mexico. These wetlands provide valuable habitat to resident and migratory waterfowl, shorebirds, mammals, and endangered species, including the Yuma Clapper Rail and the Desert Pupfish. Both wetlands are currently threatened by water management actions that do not take the wetland value of agricultural drainage into consideration. If agricultural drainage water and other available waste streams were explicitly managed to support wetlands, the Colorado River detla could potentially contain 50,000 ha or more of permanent, high-quality brackish wetlands below the agricultural fields.

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Mahdi Abdal and Majda Sulieman

Agricultural development in Kuwait faces many problems and obstacles, such as limitation of water resources for irrigation, soils conditions, climatic extreme (particularly during the summer periods), and trained labor. With these extreme conditions for agricultural development in Kuwait, there is a strong demand from the public and the government for agricultural activities, particularly in urban landscape and greenery. World travel has enhanced the public's desire for the beautification of the urban areas and has emphasized the importance of the urban landscape. Planning urban landscape and greenery for Kuwait depends on various variables and efficient management of limited resources. Irrigation water is limited in Kuwait, and the quality of water is deteriorating from over-pumping of underground water and increased soil salinity by over irrigation and lack of drainage. Efficient irrigation-water management can be improved in Kuwait with enhanced irrigation research and implementation of the recommendations of this research. Research topics can also include water evaporation, which is high in Kuwait, and the introduction of mulching materials to improve water irrigation efficiency. Most of the soils in Kuwait are sandy with limited organic materials and plant nutrients. Research in soil fertility and plant uptake of nutrients is essential for any agricultural activities. Introducing ornamental plants tolerant to drought, salinity, and heat is a continuous research component of urban landscape and greenery in Kuwait. Training local staff in basic agricultural activities and research development should improve resource management and enhance the greenery of Kuwait.

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Helene Murray, Donald L. Wyse, and Emily E. Hoover

Minnesota has a long history of strong citizen involvement in environmental, community development, economic development, and human rights issues. Therefore, it is not surprising there are many individuals, organizations, communities, and educational institutions in Minnesota actively involved in the sustainable agriculture debate. The challenge we face is how to help these strong forces work in collaboration to solve rural problem s.

In 1990 representatives of five community-based organizations and the U of M agreed to form the Minnesota Institute for Sustainable Agriculture (MISA) to be housed at the University and governed by a board of community and University representatives. The purpose of MISA is to bring farmers and other sustainable agriculture community interests together with University administrators, educators, researchers, and students in a cooperative effort to undertake innovative, agenda-setting programs that might not otherwise be pursued in the state.

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Matthew Rogoyski, Alvan Gaus, Thomas Mourey, Israel Broner, and Jeffrey Lakey

A novel way to capture long-standing agricultural experience and knowledge in the form of generative patterns is proposed. These patterns can be thought of as solution paradigm where the solutions are the essence of the patterns. A pattern does not provide a concrete solution to a problem but can be considered of as a worldview of the problem or a solution space. A pattern initiates and generates human cognitive behaviors that indirectly facilitate, elucidate, and solve a problem. An application of generative patterns to production agriculture is proposed. An individual pattern, as described here, associates a problem, its context, the forces affecting it, and a solution. A pattern recurring in production agriculture, the socalled uniformity pattern, is presented, and its horticultural example is discussed.

Open access

Edwin B. Oyer

Abstract

A recent World Bank report (8) classed over half (73 of 125) of the countries listed in its World Development Indicators as low-income or lower middle-income economies. Their per capita gross national products (GNP) are less than $1700, with a range of $80 to $1630. Agriculture contributes from 24% to 75% of their national gross domestic products, and a majority of their citizens live in rural areas although they may not be directly involved in farming. The adult literacy rate for these countries ranges from 5% to 95%. The authors state that “Agricultural production is a key factor in the development of most countries. In the poorest countries, it is critical.”