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What is an agroecosystem?. Biophysical and socioeconomic components Boundaries and hierarchies Structure and function History and legacy. Agroecosystem checklist (1) (Brookfield et al., 2002).
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What is an agroecosystem? • Biophysical and socioeconomic components • Boundaries and hierarchies • Structure and function • History and legacy
Agroecosystem checklist (1) (Brookfield et al., 2002) • Management:field types and edges; site and field surface preparation; soil and water conservation; soil fertility maintenance; planting materials; cropping patterns and rotations; weeds and weeding, pests and diseases; crop harvesting, processing, and storage; livestock; woodlots; fallow areas; wild areas
Agroecosystem checklist (2) (Brookfield et al., 2002) • Biophysicalstructure and processes:physical features at landscape and field levels; soil characteristics; soil erosion, degradation, and enhancement; microclimates
Agroecosystem checklist (3) (Brookfield et al., 2002) • Organization:land tenure; farmer gender; land ownership history; crop and tree ownership; land-use history; land-use intentions; types of livestock; off-farm employment; food security; water supplies; fuel supplies; labor supplies; transportation networks; marketing; decision-making processes
Agroecosystems are often studied as part of an effort to change them
The Evolution of Farming Systems Research (Hart, 2000) • Scale of target systems:from crop populations to whole farms to communities and watersheds • System performance criteria:from production to stability to sustainability • Targeted beneficiaries:from ‘small farmers’ to men and women to future generations • Relationships: recognition of hierarchies
Sustainability in the Context of Farming Systems Research(Hart, 2000) • A group of production technologies (e.g. cover crops) • Maintenance of the natural resource base upon which production depends • A measure of intergenerational equity
Participatory Rural Appraisal • ‘Empowering rather than extractive’ • Outsiders as facilitators rather than investigators • Information owned, analyzed, and used by local people rather than outsiders • Often conducted by NGOs rather than universities and government agencies
Prototyping Integrated and Ecological Arable Farming Systems (Vereijken, 1997) • Establish a hierarchy of objectives • Transform objectives into quantifiable performance parameters • Design and test prototypes that link socioeconomic and biophysical objectives with multi-faceted farming methods • Place prototypes on pilot farms • Refine and adapt prototypes • Disseminate prototypes to other farms
Components of a farm’s ‘identity card’ (Vereijken, 1997) • Abiotic environmental characteristics (soil, water, and air quality) • Non-agricultural species diversity (ecological infrastructure) • Food supply (quality and quantity) • Health and safety (including pesticide impacts) • Income and profit (farm and regional levels)
Farming methods for I/EAFS • Multifunctional crop rotation • Nutrient balance • Ecological infrastructure: restoration and maintenance of landscape elements • Farm structural optimization (land, labor, capital goods, technologies)
Principles of Agroeocosystem Analysis (Conway, 1986) • It isn’t necessary to know everything about an agroecosystem in order to produce a realistic and useful analysis (‘optimal ignorance’). • Understanding the behavior and important properties of an agroecosystem requires knowledge of only a few key functional relationships. • Producing significant improvements in the performance of an agroecosystem requires changes in only a few key management decisions. • Identification and understanding of these key relationships and decisions requires a limited number of key questions are defined and answered.
Tractors and water buffaloes in Sri Lanka (Senanayake, 1984; Conway, 1986) • Land area for rice vs. land for wallows and non-crop vegetation • Protein sources: buffalo milk, fish • Refugia for fish, snakes, lizards • Bund-boring crabs • Rats • Mosquitoes and malaria
Agroecosystem Analysis: Tools (Conway, 1986) • Diagrammatic historyof the site, including major events • Maps and transectsshowing important features, including topography, soils, land use, problems, opportunities • Seasonal calendarsfor climate, crop sequences, livestock, non-farm activities, labor requirements, capital requirements, income, monthly prices • Long-term graphsshowing prices, yields, acreages, population trends (births, deaths, emigration, immigration) • Bar diagramsshowing sources of farm income, expenses on different types of production inputs, etc. • Flow diagramsshowing production and marketing chains, flows of income • Decision treesdepicting choice points, key factors • Venn diagramsdepicting overlapping institutions affecting decision-making
A tentative plan (I) • Develop awareness of ecological, agronomic, and socio-economic components • Identify information needs and form information gathering groups • Identify tools for organizing and presenting information • Meet with farmers at ISU and/or on farm • Assemble information, by groups
A tentative plan (II) • Present information to classmates at debriefing following farm visits • ‘Triangulate’ to determine accuracy of information • Assemble conceptual models of farms as natural resource/human activity systems: system boundaries, components, interactions, feedbacks, control points • Identify key questions, hypotheses, and possible changes • Assess impacts of proposed changes: ecological, agronomic, socioeconomic
Some focal areas • Natural resources:soils, water sources and drainage, water quality, non-cultivated species, agricultural and non-agricultural land use • Crop and livestock systems:species, synergies and conflicts, economics, nutrient dynamics, pest management systems, calendars, buildings and machinery, product identity, target markets • Family: structure, gender issues, needs, goals, constraints, decision processes, values, off-farm jobs, land tenure, credit and debt, assets • Local community:neighbors, medical and educational services, social network, labor sources • Private and producer organizations:inputs, marketing channels, consultants, financing, information • Government: subsidies, quality assurance, regulations, information • Local and regional history and future trajectories
Tasks • Identify information gathering groups • Specify preferences for groups • Develop questions and framework for interviews and on-farm surveys