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BAHAN KAJIAN PRINSIP-PRINSIP AGROEKOSISTEM Diabstraksikan oleh: SOEMARNO Malang , 2012

BAHAN KAJIAN PRINSIP-PRINSIP AGROEKOSISTEM Diabstraksikan oleh: SOEMARNO Malang , 2012. AGROEKOSISTEM. An agroecosystem is the basic unit of

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BAHAN KAJIAN PRINSIP-PRINSIP AGROEKOSISTEM Diabstraksikan oleh: SOEMARNO Malang , 2012

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  1. BAHAN KAJIAN PRINSIP-PRINSIP AGROEKOSISTEM Diabstraksikan oleh: SOEMARNO Malang , 2012

  2. AGROEKOSISTEM An agroecosystem is the basic unit of study for an agroecologist, and is somewhat arbitrarily defined as a spatially and functionally coherent unit of agricultural activity, and includes the living and nonliving components involved in that unit as well as their interactions. (Agro-ecosystem Health Project. 1996. Agroecosystem health. University of Guelph, Guelph, Canada.) http://en.wikipedia.org/wiki/Agroecosystem ….. Diunduh 22/2/2012

  3. An agroecosystem can be viewed as a subset of a conventional ecosystem. As the name implies, at the core of an agroecosystem lies the human activity of agriculture. However, an agroecosystem is not restricted to the immediate site of agricultural activity (e.g. the farm), but rather includes the region that is impacted by this activity, usually by changes to the complexity of species assemblages and energy flows, as well as to the net nutrient balance. Traditionally an agroecosystem, particularly one managed intensively, is characterized as having a simpler species composition and simpler energy and nutrient flows than "natural" ecosystem. Elske van de Fliert and Ann R. Braun. 1999. Farmer Field School for Integrated Crop Management of Sweetpotato. Field guides and Technical Manual. Bogor, Indonesia: International Potato Center. ISBN 92-9060-216-3. http://www.eseap.cipotato.org/MF-ESEAP/Abstract/FFS-ICM-SP-Ind.htm http://en.wikipedia.org/wiki/Agroecosystem ….. Diunduh 22/2/2012

  4. Agroecosystem analysis is a thorough analysis of an agricultural environment which considers aspects from ecology, sociology, economics, and politics with equal weight. There are many aspects to consider; however, it is literally impossible to account for all of them. This is one of the issues when trying to conduct an analysis of an agricultural environment. In the past, an agroecosystem analysis approach might be used to determine the sustainability of an agricultural system. It has become apparent, however, that the "sustainability" of the system depends heavily on the definition of sustainability chosen by the observer. Agroecosystem analysis is used to bring the richness of the true complexity of agricultural systems to an analysis to identify reconfigurations of the system (or holon) that will best suit individual situations. Diunduh dari: http://en.wikipedia.org/wiki/Agroecosystem_analysis

  5. Agroecosystem analysis is a tool of the multidisciplinary subject known as Agroecology Agroecology and agroecosystem analysis are not the same as sustainable agriculture, though the use of agroecosystem analysis may help a farming system ensure its viability. Agroecosystem analysis is not a new practice, agriculturalists and farmers have been doing it since societies switched from hunting and gathering (hunter-gatherer) for food to settling in one area. Every time a person involved in agriculture evaluates their situation to identify methods to make the system function in a way that better suits their interests, they are performing an agroecosystem analysis. Diunduh dari: http://en.wikipedia.org/wiki/Agroecosystem_analysis

  6. Agro-ecosystems, natural resources management and human health related research in East Africa: Case studies Agro-ecosystem health: Principles and methods used in high-potential tropical agro-ecosystem T.Gitau,J.J.McDermott2,3,D. Waltner-Toews3,J.M. Gathuma1, E.K.Kang1, V.W.Kimani4, J.K.Kilungo5, R.K. Muni6, J.M. Mwangi1 and G.O. Otieno7 A simplified conceptual model of the agro-ecosystem. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Agro.htm

  7. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 Some basic definitions for agroecosystem assessment. Agroecosystems and agricultural technology systems It is necessary to start with some definitions, including the distinction between agroecosystems and agricultural technology systems. An agroecosystem is a complex of air, water, soil, plants, animals, micro-organisms, and everything else in a bounded area that people have modified for the purposes of agricultural production. An agroecosystem can be of any specified size. It can be a single field, it can be a household farm, or it can be the agricultural landscape of a village, region, or nation. Sumber: http://www.gerrymarten.com/publicatons/agroecosystem-Assessment.html

  8. AGROECOSYSTEM PROPERTIES Productivity - the quantity of food, fuel or fiber that an agroecosystem produces for human use. Stability - consistency of production. Sustainability - maintaining a specified level of production over the long term. Equitability - sharing agricultural production fairly. Autonomy - agroecosystem self-sufficiency.

  9. Plant Nutrient Balances in the Asian and Pacific Region - the Consequences for Agricultural Production Ernst W. MutertEast & Southeast Asia Program, Potash & Phosphate Institute,126 Watten Estate Road, Singapore 287599, 1995-11-01 Asia and the Pacific will have to feed an additional 1.8 billion people over the next 30 years. It is vital for the region's future to meet the rising food demand from a limited production area by intensification. The recent stagnation of rice yields observed in the lowlands of the region has become a major agronomic concern. The main reasons are a decrease in nutrient productivity and an increasing imbalance in the nutrient supply. Nutrient input/output balances for main crops and for rice in ten selected Asian countries are presented. Negative balances for N, P, K, Mg, Ca, to a total of 7 million mt, were observed in lower income economies with large and growing populations (e.g. Bangladesh, Indonesia, Myanmar, Philippines, Thailand, Vietnam). An oversupply of nutrients (a total of 1.1 million tons) was found in higher income economies with stable populations (Japan, Korea, Malaysia). The principle of balanced fertilization requires that this damaging trend be halted through judicious use of fertilizers, in order to sustain an economically viable and environmentally friendly agriculture which meets the requirements of the future.

  10. Plant Nutrient Balances in the Asian and Pacific Region - the Consequences for Agricultural Production Ernst W. MutertEast & Southeast Asia Program, Potash & Phosphate Institute,126 Watten Estate Road, Singapore 287599, 1995-11-01 NERACA HARA DALAM SUATU AGROEKOSISTEM

  11. Plant Nutrient Balances in the Asian and Pacific Region - the Consequences for Agricultural Production Ernst W. MutertEast & Southeast Asia Program, Potash & Phosphate Institute,126 Watten Estate Road, Singapore 287599, 1995-11-01

  12. Plant Nutrient Balances in the Asian and Pacific Region - the Consequences for Agricultural Production Ernst W. MutertEast & Southeast Asia Program, Potash & Phosphate Institute,126 Watten Estate Road, Singapore 287599, 1995-11-01 Figure 1 Rothamsted 1852-1967: Comparison of Wheat Yields

  13. Plant Nutrient Balances in the Asian and Pacific Region - the Consequences for Agricultural Production Ernst W. MutertEast & Southeast Asia Program, Potash & Phosphate Institute,126 Watten Estate Road, Singapore 287599, 1995-11-01 Figure 2 Trends in the Use of N Versus P and K in Europe and North America, Relative to Asia Source: vonUexlullandMutert1993

  14. Agro-ecosystems, natural resources management and human health related research in East Africa: Case studies Agro-ecosystem health: Principles and methods used in high-potential tropical agro-ecosystem T.Gitau,J.J.McDermott2,3,D. Waltner-Toews3,J.M. Gathuma1, E.K.Kang1, V.W.Kimani4, J.K.Kilungo5, R.K. Muni6, J.M. Mwangi1 and G.O. Otieno7 Hierarchy in agro-ecosystems: The central highlands of Kenya. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Agro.htm

  15. Agro-ecosystems, natural resources management and human health related research in East Africa: Case studies Agro-ecosystem health: Principles and methods used in high-potential tropical agro-ecosystem T.Gitau,J.J.McDermott2,3,D. Waltner-Toews3,J.M. Gathuma1, E.K.Kang1, V.W.Kimani4, J.K.Kilungo5, R.K. Muni6, J.M. Mwangi1 and G.O. Otieno7 PAR (participatory action research) tools used in the study and the expected outputs. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Agro.htm

  16. Agro-ecosystems, natural resources management and human health related research in East Africa: Case studies Agro-ecosystem health: Principles and methods used in high-potential tropical agro-ecosystem T.Gitau,J.J.McDermott2,3,D. Waltner-Toews3,J.M. Gathuma1, E.K.Kang1, V.W.Kimani4, J.K.Kilungo5, R.K. Muni6, J.M. Mwangi1 and G.O. Otieno7 A simplified conceptual model of the agro-ecosystem. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Agro.htm

  17. Concepts of sustainability, agro-ecosystem health and applications to agricultural production1 B. Smit University of Guelph, Guelph, Ontario, Canada Production, resources management and human health in East African highlands: A summary of the issues as outlined in ILRI (1998). Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Concepts.htm

  18. Concepts of sustainability, agro-ecosystem health and applications to agricultural production1 B. Smit University of Guelph, Guelph, Ontario, Canada Agricultural sustainability and agro-ecosystem health Once the term 'agro' is appended to 'ecosystem' we have explicitly included human components, such that 'agro-ecosystem' is fundamentally equivalent to a broad definition of 'agriculture', which includes ecological and human components. Sustainable agriculture has been defined in many ways (Smit and Brklacich 1989; Cai and Smit 1994; Smit and Smithers 1994b), but most cover the same essential features. Consider two representative definitions: agri-food systems that are economically viable, meet society's need for safe and nutritious foods, while conserving natural resources and the quality of the environment for future generations (SCC 1992), and agricultural system that can indefinitely meet demands for food and fibre at socially acceptable economic and environmental costs (Crosson 1992). In both of these, agricultural sustainability is defined with respect to societal needs or demands for food, including nutrition, and hence implying human health economic viability, referring to the maintenance of production systems, and environmental quality, addressing the condition of biophysical resources. Definitions of sustainability also note the maintenance of these features over time ('future generations' or 'indefinitely'). Definitions of agro-ecosystem health cover essentially the same features. Waltner-Toews (1994) and Smit and Smithers (1994b) describe agro-ecosystem health as incorporating human well-being economic performance, and ecological condition. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Concepts.htm

  19. Concepts of sustainability, agro-ecosystem health and applications to agricultural production1 B. Smit University of Guelph, Guelph, Ontario, Canada the essence of the agro-ecosystem health (AESH) perspective is that it recognises the existence of, and interrelationships among, these several domains of agricultural systems (economic, human and ecological), and that the overall 'health' of the system is a function of the condition, of and interdependencies among, these components. A simple conceptualisation of agro-ecosystem health is given in Figure (from Smit and Smithers 1994b). Agro-ecosystem health: A sample diagramatic representation. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Concepts.htm

  20. Concepts of sustainability, agro-ecosystem health and applications to agricultural production1 B. Smit University of Guelph, Guelph, Ontario, Canada The conceptual foundations of these two paradigms, AESH and agricultural sustainability (AS), are fundamentally synonymous. Both are explicitly evaluative of the overall conditions of rural environments, economies, and peoples. It is noteworthy that the goals of CGIAR also mirror these components increase food security alleviate poverty, and protect environmental quality. In other respects as well, AESH and AS are very similar. Both are applicable at different spatial and temporal scales (Smit and Smithers 1994a). For both, considerable effort has been expended in developing indicators, and similar kinds of indicators (often very long lists) have been proposed. Indicators can take a wide variety of forms, including state and functional indicators, diagnostic and early warning indicators (Smit et al 1998). There are also many examples of particular empirical studies employing indicators, especially of sustainable agriculture (Smit and Smithers 1994a), but also for agro-ecosystem health (Smit et al 1998). Smit B. and Smithers J. 1994a. Sustainable agriculture: Interpretations, analyses and prospects. Canadian journal of regional science 16(3):499–524. Smit B., Waltner-Toews D., Rapport D., Wall E., Wichert G., Gwyn E. and Wandel J. 1998. Agro-ecosystem health: Analysis and assessment. University of Guelph, Guelph, Canada. Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Concepts.htm

  21. Concepts of sustainability, agro-ecosystem health and applications to agricultural production1 B. Smit University of Guelph, Guelph, Ontario, Canada Approaches to agro-ecosystem health indicators Holistic This approach, of which several versions have been proposed, aims to define a set of very generic 'criteria', essentially from first principles, which will be applicable to all dimensions. Thus, we get such 'holistic indicators' as integrity, efficiency, resilience, effectiveness, response capability, balance, richness, transformation ability, self-regulatory capacity, flexibility, stability, and so on (Figure : A conceptual framework for agro-ecosystem health). Diunduh dari: http://www.ilri.org/InfoServ/Webpub/fulldocs/Aesh/Concepts.htm

  22. Dennis S. Ojima and William J. Parton Integrated Approach to Land Use Analyses a hierarchical or spatially nested analytical framework is needed in order to understand how driving forces of land use and climate changes transform land covers at local to regional scales . Analytical structure for assessment of land and climate change effects on agroecosystems of the US Great Plains. Diundu dari: http://www.ncgia.ucsb.edu/conf/SANTA_FE_CD-ROM/sf_papers/ojima_dennis/ojimapar.html

  23. Dennis S. Ojima and William J. Parton Integrated Approach to Land Use Analyses Our ability to predict ecosystem dynamics relative to climate or land use changes is dependent on the development of analytical tools to integrate our current understanding of how these ecosystems behave relative to human and environmental factors. The analysis of this information will need to incorporate the critical factors of the physical environment, including climate and soil factors, but also include the human factors related to land use practices (Figure ). The dynamics of the agroecosystem will depend on the joint influence of the physical environment and the specific mix of land use practices implemented with a location. The land use decisions are controlled by a number of factors economics, policy, technological advancements, and socio- cultural factors. Simplified structure of the CENTURY agroecosystem model (Parton et al 1987, 1995) indicating the physical environmental controls and the set of land use management options implemented. Parton, W.J., Schimel, D.S., Cole, C.V., and Ojima, D.S. (1987) Analysis of factors controlling soil organic matter levels in Great Plains grasslands. Soil Science Society of America Journal 5:1137-1179. 465

  24. Dennis S. Ojima and William J. Parton Integrated Approach to Land Use Analyses A framework to simplify the complex interactions within and between various subsystems is provided using a modeling approach that includes all the major components and links them together in a spatially integrated fashion (Figure: Linkage of social-cultural-economic factors influencing the land use decisions which modify agroecosystem processes).

  25. Dennis S. Ojima and William J. Parton Integrated Approach to Land Use Analyses In recent analysis of assessing changes in land use management in the corn belt region of the United States, CENTURY simulations of improved land use practices resulted in a recovery of 47 to 79% of the initial soil C lost after approximately 50y of cropping (Figure 4, modified from Parton et al., 1995, Donigian et al. 1995). These analyses indicate that changes in land management practices can affect C storage in the soil without greatly affecting yield of corn in this region. The factors influencing crop rotation and crop selection also affected the level of C stored in this mesic region of the US (Donigian et al. 1995). Figure: The effect of changing land management in the cornbelt of the United States on soil carbon levels in the surface 20 cm of soil. Donigian, A.S., Jr, PatwardhamA.S., Jackson, R.B. IV, Barnwell, Jr., T.O., Weinrich, K.B. and Rowell, A.L. 1995. Modeling the impacts of agricultural management practices on soil C in the Central US. P.121- 145. In R. Lal, J. Kimble, E. Levine, and B.A. Stewart (eds.), Soil Management and Greenhouse Effect. Advances in Soil Science. CRC Press. Boca Raton, FL. Parton, W.J., Ojima, D.S., and Schimel, D.S. (1995) Models to evaluate soil organic matter storage and dynamics. In M.R. Carter and B.A. Stewart (eds.) Structure and Organic Matter Storage in Agricultural Soils. Advances in Soil Science. CRC Press. Boca Raton, FL.

  26. IPM systems modelling To further illustrate the previous points on the possibilities of systems modelling in IPM some additional explanation is provided. The research components of a typical IPM modelling application are found in Figure (Components of Agroecosystem Analysis). At the ecosystem level, the integrating technologies are modelling and GIS. Population models must be built up from the individual physiological and behavioural level and be driven by soil factors and weather. Policy issues must include social science components impinging on the agroecosystem structure and function. Diunduh rari: http://www.fao.org/WAIRDOCS/TAC/Y4847E/y4847e07.htm

  27. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 The Southeast Asian Universities Agroecosystem network (SUAN) has used five system properties to assess agroecosystem performance: productivity, stability, sustainability, equitability and autonomy. Assessing these properties can be useful for agricultural research and development, but the assessment is complicated by several factors. First is the multidimensional character of these properties, due to (a) independent measures of agricultural production and (b) differences in the same property at different hierarchical levels of an agroecosystem. Secondly, there are significant limitations in generalizing agroecosystem assessment from one set of environmental and social conditions to another. The SUAN network has examined trade-offs between these properties and implications of the trade-offs for agroecosystem design. Increases in productivity can be at the expense of other system properties, or they can be mutually reinforcing, depending on how the agroecosystem is organized. System Properties Agroecosystems are overwhelmingly complex. The numerous ecological processes that tie people, crops, weeds, animals, micro-organisms, soil, and water together into a functioning, on-going ecosystem are so intricate that they can never be fully described, nor can they be fully comprehended. Simplification is a practical necessity of analysis. Simplification is also essential for effectively communicating the results of analysis to agricultural practitioners. The dilemma is how to simplify without losing the essence of key relationships in the agroecosystem as a whole. One approach to simplification is system properties (also called agroecosystem properties in this essay), which combine large numbers of agroecosystem processes into single, highly-aggregated measures of performance that suggest how well an agroecosystem is meeting human objectives (Gypmantasiri et al, 1980; Conway, 1985; Rerkasem & Rambo, 1988). The SUAN network has focused on five system properties: Productivity - the quantity of food, fuel or fiber that an agroecosystem produces for human use. Stability - consistency of production. Sustainability - maintaining a specified level of production over the long term. Equitability - sharing agricultural production fairly. Autonomy - agroecosystem self-sufficiency.

  28. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 Differences in the Agroecosystem Production Properties of Two Hypothetical Agricultural Technology Systems

  29. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 Multidimensional character of stability and sustainability Stability concerns fluctuations in productivity that result from numerous fluctuations in an agroecosystem's physical and social environment: variations in rainfall, periodic pest attacks, price fluctuations, etc. Stability is assessed in terms of the fluctuation of production about a long-term average (Fig. 2) or the fluctuation of production about a long-term trend. The stability concept can be described in abstract terms by considering movements of a small ball on the landscape, as in Fig. 3. The position of the ball on the landscape represents all the numerous aspects of agroecosystem organization and function, including production; point A represents the average condition of the agroecosystem (including its production). Stability concerns movement of the ball about point A under the impact of disturbances that are not large enough to knock the ball all the way out of the valley. Less movement (i.e. less fluctuation in production) represents greater stability. Because stability derives from productivity, stability is multidimensional in exactly the same respects. A given agroecosystem can be relatively stable with regard to some measures of productivity and low with regard to others. Maize production for subsistence can be considered stable as long as yields (and therefore food production) are consistent, but the same crop may be considered unstable if grown for a market economy with fluctuating prices. The meaning of stability and sustainability in terms of the time course of production.

  30. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 In the abstract view of Fig. 3, sustainability involves the ability of farm management to maintain agroecosystem function (including production) at point A, despite natural ecological processes that tend to change the agroecosystem toward point B. As with stability, sustainability has a variety of measures associated with various measures of productivity. Some measures of sustainability can be high while others are low for the same agroecosystem. The multidimensionality of sustainability derives in large part from the fact that it may be necessary to increase certain inputs with successive crops to maintain yields at the same level. For example, if increasing fertilizer inputs are required to sustain production per hectare at a given level, the production per hectare may be sustainable even though production per unit cost is not. If weed problems require increasing labor inputs, production per hectare may be sustained while production per unit of labor is not. A ball and landscape model for visualizing stability and sustainability concepts. The horizontal axis of the diagram represents different states of ecosystem structure and function.

  31. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 Resilience is intermediate between stability and internal sustainability. Like stability, resilience concerns the response of production to external disturbance; like sustainability, resilience concerns the maintenance of production. Stability concerns routine fluctuations in response to frequent and generally tolerable disturbances, while resilience deals with whether the agroecosystem can persist in the face of disturbances that are occasional but traumatic. The same agroecosystem can be quite strong with regard to internal sustainability but low in resilience, or visa versa, because these two kinds of sustainability involve different processes. Relationships of stability, resilience and sustainability. Diunduh dari: http://www.gerrymarten.com/publicatons/agroecosystem-Assessment.html

  32. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 Agroecosystem Strucutal Properties Agroecosystem structure is a consequence of the particular crops and other components (weeds, animal pests, soil animals, micro-organisms, etc.) in an agroecosystem, the way those components are structured by farm management practices, and the way those components are related functionally to one another. SUAN research has dealt with numerous aspects of ecosystem structure and their relationships to agroecosystem function (Table ). However, the SUAN network has not dealt much with agroecosystem structure at the same organizational level as system properties for agroecosystem production. It could be useful for agro-ecosystem research to identify those structural system properties (at the agroecosystem level of organization) that in fact have strong relationships with the production properties. Such structural properties could prove useful as guidelines for agroecosystem design. Table: Examples of Relationships Between Agroecosystem Structure and Agroecosystem Function that have been Studied in the SUAN Network Diunduh dari: http://www.gerrymarten.com/publicatons/agroecosystem-Assessment.html

  33. An example of the causal connections between system properties of agroecosystem structure and system properties of agroecosystem production. Agroecosystem structure and adaptability One approach to delineating functional connections between system properties of agroecosystem structure and production is to address select properties of agroecosystem function (in addition to those concerning production). Adaptability (Holling, 1978) is an example of a functional property that can help to bridge the gap between structure and production. Holling, C. S. (1978). Adaptive environmental assessment and management, Wiley, New York. Diunduh dari: http://www.gerrymarten.com/publicatons/agroecosystem-Assessment.html

  34. Productivity, Stability, Sustainability, Equitability and Autonomy as Properties for Agroecosystem Assessment Gerald G. Marten Agricultural Systems 26 (1988) 291-316 Basic elements in a corrective feedback loop for adaptive agroecosystem design. Crop diversity can improve nutritional productivity only if there is a proper mix of crops (Abdoellah & Marten, 1986): some that have high yields to produce large amounts of certain nutrients (e.g. calories and protein) that are needed in large quantities; and other crops that provide smaller quantities of a variety of nutrients for nutritional balance (e.g. vitamin A, vitamin C, riboflavin, calcium, and iron when rice is the staple food). Abdoellah, O. S. & Marten, G. G. (1986). The complementary roles of homegardens, upland fields, and rice fields for meeting nutritional needs in West Java. In: Traditional agriculture in Southeast Asia. (Marten, G. G. (Ed)), Westview Press, Boulder, Colorado, 293-315. Diunduh dari: http://www.gerrymarten.com/publicatons/agroecosystem-Assessment.html

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