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1 This article was downloaded by: [Carlos Gonzalez-Esquivel] On: 15 September 2011, At: 07:12 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: Registered office: Mortimer House, Mortimer Street, London W1T 3JH, UK International Journal of Agricultural Sustainability Publication details, including instructions for authors and subscription information: Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems: analysing 15 case studies from Latin America Marta Astier a, Erika N. Speelman b, Santiago Lóópez-Ridaura c, Omar R. Masera d & Carlos E. Gonzalez-Esquivel e a Centro de Investigaciones en Geografia Ambiental, Universidad Nacional Autonoma de Mexico, Antigua Carretera a Patzcuaro 8701, Col. Exhacienda de San Jose de la Huerta, CP 58190, Morelia, Michoacan, Mexico b Biological Farming Systems, Plant Sciences Group, Wageningen University, Droevendaalsesteeg 1, 6708, PB, Wageningen, The Netherlands c Institut National de la Recherche Agronomique, UMR Innovation, Campus de la Gaillarde 2, place Viala 34060, Montpellier, France d Centro de Investigaciones en Ecosistemas, Universidad Nacional Autóónoma de Mééxico, Antigua Carretera a Páátzcuaro 8701, Col. Exhacienda de San Jose de la Huerta, CP 58190, Morelia, Michoacáán, Mexico e InCrops Enterprise Hub, University of East Anglia, Norwich, NR4 7TJ, UK Available online: 15 Sep 2011 To cite this article: Marta Astier, Erika N. Speelman, Santiago Lóópez-Ridaura, Omar R. Masera & Carlos E. Gonzalez-Esquivel (2011): Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems: analysing 15 case studies from Latin America, International Journal of Agricultural Sustainability, 9:3, To link to this article: PLEASE SCROLL DOWN FOR ARTICLE Full terms and conditions of use: This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, re-distribution, re-selling, loan, sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae

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3 Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems: analysing 15 case studies from Latin America Marta Astier 1, Erika N. Speelman 2, Santiago López-Ridaura 3, Omar R. Masera 4 and Carlos E. Gonzalez-Esquivel 5 * 1 Centro de Investigaciones en Geografia Ambiental, Universidad Nacional Autonoma de Mexico, Antigua Carretera a Patzcuaro 8701, Col. Exhacienda de San Jose de la Huerta, CP Morelia, Michoacan, Mexico 2 Biological Farming Systems, Plant Sciences Group, Wageningen University, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands 3 Institut National de la Recherche Agronomique, UMR Innovation, Campus de la Gaillarde 2, place Viala 34060, Montpellier, France 4 Centro de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Col. Exhacienda de San Jose de la Huerta, CP Morelia, Michoacán, Mexico 5 InCrops Enterprise Hub, University of East Anglia, Norwich NR4 7TJ, UK In view of the urgent need to improve agroecosystem sustainability, several efforts have been made to evaluate the effect of alternative strategies on key environmental and socioeconomic variables at the farm, community and regional levels. Most peasant farmers manage complex and diverse agroecosystems, and constantly adapt management strategies with multiple aims. A sustainability evaluation framework for peasant systems has been applied in over 40 case studies in Latin America, from which 15 were analysed, focusing on the choice of indicators, the effect of alternative strategies on agroecosystem sustainability and the trade-offs involved. Common indicators include yields, income, agrodiversity and external input dependence. Alternative strategies include crop/product diversification and soil conservation practices. Yields, income and agrodiversity improved in most cases, but in some cases the establishment costs increased external input use. Trade-offs observed include improved performance of a subsystem (i.e. crops) vs. decreased one in others (livestock, forestry) and increases in productivity vs. decreases in stability, resilience and reliability. The difficulty of assessing systems in transition towards alternative management was acknowledged by some evaluation teams. Applying the framework to such a variety of cases allowed making the sustainability concept operational, promoted alternative strategies and generated knowledge on agroecosystem processes among stakeholders. Keywords: indicators; MESMIS framework; peasant agroecosystems; sustainability evaluation; trade-offs Introduction Sustainable development can be broadly defined as the process by which material and spiritual needs of human population would be met, without degrading and even improving the socio-environmental conditions that sustain them (Masera et al., 1999). Applying this concept to natural resource management systems, these must comply with seven attributes, to be considered sustainable (López-Ridaura et al., 2005; Rao and Rogers, 2006; Astier et al., 2008): High level of productivity by means of an efficient and synergic use of natural and economic resources. Stability, reliability and resilience, referring to the presence and effectiveness of the negative feedback processes that allow maintenance of a state of *Corresponding author. cgesquivel@hotmail.com 9(3) 2011 PAGES , doi: / # 2011Earthscan Taylor & Francis Group aninformabusiness. ISSN: (print), X (online).

4 410 M. Astier et al. dynamic balance at a constant productivity level, under normal, shock or stress conditions. Adaptability to cope with changing socioenvironmental conditions. Equity in the distribution of costs and benefits amongst the different users of resources. Self-reliance, implying enough independence and self-sufficiency to maintain their performance despite the occurrence of external changes. Some authors have used most of these attributes, but named them differently (Pretty, 2008); others have studied agroecosystem sustainability only through resilience (Walker and Salt, 2006; Mayer, 2008). Any natural resource management system is by these attributes or principles unsustainable if it depends on non-renewable inputs, cannot consistently and predictably deliver desired outputs, can only do this by requiring the cultivation of more land and/or causes adverse and irreversible environmental impacts that threaten critical ecological functions (The Royal Society, 2009). Along with the increase in sustainability-oriented policies at the regional and national levels, the need to improve information systems of decision-making in natural resource management has been emphasized. This includes the design and monitoring of sustainability indicators (UNDP, 1993). Some of the evaluation frameworks include the pressure-stateresponse model of the OECD, mainly used at the national level, or those aimed at the public to calculate the environmental impact of human activity, such as the ecological footprint (Wackernagel and Rees, 1996; OECD, 2001). An important stream of sustainability-oriented studies is based on an agroecosystems approach. Agroecosystems can be defined as resource management systems aimed at agricultural or forest production. The need to reduce their environmental impact and their risks to human health has led to substantial work in strategies such as reducing or replacing synthetic fertilizers and pesticides, reintroducing traditional practices such as intercropping and applying integrated fertility and pest management strategies, in order to reduce energy, nutrient and economic losses. It is therefore fundamental to analyse the impact of such practices on the sustainability of agroecosystems at the farm, community and regional levels. An important contribution to sustainability evaluation is the use of environmental impact studies (EIS) on agricultural systems. According to Thomassen and de Boer (2005), some examples of EIS include input output analyses, ecological footprints and life cycle assessments. The most relevant indicators used in such studies include the use of external inputs, greenhouse gas emissions and nutrient balances. Other studies have concentrated on the evaluation of a few agri-environmental indicators, such as soil quality (Doran, 2002), pesticide use, crop rotation and fertility management (Braband et al., 2003; Abbona et al., 2007) or agricultural biodiversity (Büchs et al., 2003; Duelli and Obrist, 2003). Since EIS by definition do not comprise socioeconomic aspects, sustainability evaluations involving the complexity of agroecosystems are required. Diverse frameworks for agroecosystem sustainability evaluation have been proposed, but not always applied. One of the first efforts developed is the framework for the evaluation of sustainable land management (FESLM; Gameda and Dumanski, 1995). Other methodologies for agricultural systems comparison at local and regional levels include those by Andreoli and Tellarini (2000), Bosshard (2000), Tellarini and Caporalli (2000), Cornelissen (2003) and Van Cauwenbergh et al. (2007), as well as natural resource management system studies revised by Galván-Miyoshi et al. (2008) and Mayer (2008). Despite this progress, the dissemination of frameworks, indicators and results of evaluations has been slow. An important effort in this direction is the collection of case studies of agroecosystem sustainability evaluation, in which the framework for the evaluation of management systems, using indicators of sustainability (MESMIS, for its Spanish acronym), has been applied (Masera and López-Ridaura, 2000; Astier and Hollands, 2005; Speelman et al., 2007; Astier et al., 2008). This framework was originally proposed as an adaptation of the FESLM framework to peasant agroecosystems, with emphasis on Latin America. The majority of farmers in this region manage highly complex agricultural systems at a small-scale, on a subsistence level, representing 63 per cent of total farmland (ECLAC, 2009). Here, the agroecological movement has attracted millions of farmers who, through social institutions of different kinds, are pursuing more sustainable agriculture and rural communities. Alternative agriculture is practiced by integrating the key management principles for sustainability resumed by Pretty (2008): (i) biological and ecological processes such as nutrient cycling and positive biological interactions; (ii) minimizing

5 Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems 411 the use of non-renewable inputs; (iii) making productive use of farmers knowledge and skills, reintroducing traditional practices; and (iv) making productive use of people s collective capacities. Mainstream agricultural innovations in the region have shown not to be scale- or resource-independent, mostly favouring large-scale farmers in homogeneous environments (Pretty et al., 2003). Farms managed by peasants often comprise several small plots located in different agroecological zones, making blanket management improvements difficult to apply. In addition, most conventional innovations require well-endowed conditions and monetary inputs, which are usually neither present nor available to small-scale, resourcepoor, subsistence farmers. When these innovations are implemented into complex agroecosystems, there are often trade-offs between the multiple outcomes pursued by peasants (Speelman et al., 2006). Therefore, alternative, more sustainable management options are needed in order to implement the low-input, site-specific innovations appropriate for these complex agroecosystems (Pretty et al., 2003). The MESMIS framework can be considered as an influential methodology in sustainability evaluation, having been applied to more than 40 case studies across Europe and Latin America, particularly in Mexico (Speelman et al., 2007, 2008). These case studies are the basis for a great deal of detailed information on management strategies developed to increase agroecosystem sustainability. This paper presents the results of an analysis of 15 Latin American MESMIS case studies. The aims of the study were: (i) to analyse the sustainability indicators selected in the different case studies; (ii) to assess the performance of alternative resource management systems; and (iii) to analyse common strategies and trade-offs in sustainability attributes. The MESMIS framework The MESMIS framework was developed by a multiinstitutional team led by the Interdisciplinary Group of Appropriate Rural Technology (GIRA, for its Spanish acronym), a Mexican non-governmental organization (NGO). The framework has an iterative, holistic and interdisciplinary approach, which allows for a comparison of conventional and alternative management systems. Its operational structure is a cyclical one. Several phases are considered to guide and implement the process, including: defining the vision, context and objectives of the system; establishing a framework to define the dimensions, attributes and criteria, to derive indicators with their evaluation units and optimum (or ideal ) values; and finally communicating results, which will in turn provide feedback to management decisions. Once the recommendations from the evaluation process are applied, a second stage can then be initiated, thus repeating the cycle (Figure 1). The framework is built upon four principles: (i) sustainability is defined by seven dynamic, systemic attributes: productivity, stability, reliability, resilience, adaptability, equity and self-reliance; (ii) sustainability evaluations are only valid for a specific management system, on a specific spatial and temporal scale; (iii) the evaluation process is participatory, including internal and external participants; and (iv) sustainability is assessed through the comparison of systems either simultaneously (i.e. a conventional or reference system and an alternative one), or throughout time (López-Ridaura et al., 2002). The determination of sustainability criteria and indicators varies according to the approach followed by the evaluation team and the specific case under study. Thus, the application of a specific list of indicators for all situations, as well as the reduction of indicators to a single numeric index, is of little Figure 1 The MESMIS sustainability evaluation framework Source: López-Ridaura et al. (2002).

6 412 M. Astier et al. value. Therefore, criteria and evaluation methods must be specified to each case study (López-Ridaura et al., 2002). According to regional averages, expected values or desirable thresholds, optimum values have to be defined for each indicator. Articulation between objectives, indicators and reference values is a critical aspect of the evaluation process. Without clear objectives and targets, indicators can easily lead to uncertainty and misinterpretation (Potts, 2006). Another factor to consider when selecting indicators that may provide an appropriate feedback to resource users is to select those that present lower costs and operational simplicity during measurement. Methods of analysis Secondary data from 15 selected case studies were analysed. First, the 15 proposed alternative management strategies were compared in order to find those commonly proposed to improve system s sustainability. The indicators defined and measured in all case studies were then analysed and used as a proxy for the view that stakeholders have of their systems and the importance they attach to individual subsystems. Afterwards, the capacity of the alternative management system to improve sustainability was analysed by comparing the indicator values of the conventional and the alternative systems, quantitatively and qualitatively. For each case study, a qualitative value (i.e. increase or decrease) of the effect of alternative management on each indicator was put into a table, in order to create a quick synopsis. For a quantitative analysis, MESMIS proposes standardization of indicator values to allow for comparison. Standardized indicator values show the percentage in relation to an optimum value. Optimum indicator values were identified per case study. Standard indicator values of the reference systems were plotted against those of the alternative ones, in order to identify improvements and/or deterioration through alternative management, which was supposed to improve sustainability. Finally, the effect of alternative management strategies on the most commonly used indicators was investigated by means of a simple trade-off analysis. Commonly, management changes result in trade-offs, where some aspects or indicators are improved and others are worsened (Speelman et al., 2006). To identify some of these trade-offs, we selected the most commonly used strategy to improve system sustainability and the effects on some commonly used indicators in our 15 case studies. For this purpose, we calculated the difference in standardized indicator values of the alternative system minus the reference system. The values of the main strategy were plotted against the three most used indicators for all case studies. The resulting graph provides a quick view of the existing trade-offs, with the most commonly proposed road directed towards more sustainable agro-ecosystem management. Results and discussion The case studies From over 40 case studies that used the MESMIS framework in Latin America, 15 were selected to be analysed in depth. The case studies were chosen for the quality and quantity of available data and had been carried out over two to four years. Most of the case studies had been previously compiled. Masera and López-Ridaura (2000) documented five case studies carried out during a two-year period in rural Mexico. Additional seven case studies originating from Central and South America were published by LEISA Revista de Agroecología, (Gianella and Chávez, 2003), of which six were documented more extensively by Astier and Hollands (2005). Two other studies from Mexico s Central highlands were documented by Villa (2002) and Brunett et al. (2005) and another one was led by Duarte Silveira (2005) in Honduras. The analysis presented here is based on secondary data gathered from the abovementioned resources. The organizations involved in the evaluations ranged from universities and research institutes to NGOs and farmers groups, as well as to a combination of these. The main characteristics of the case studies are shown in Table 1. The majority of case studies evaluated two management systems; one being the most commonly used locally, also known as the reference system; and the other involving alternative resource management strategies aiming at increased sustainability. However, two case studies used a different approach to define the evaluated systems. In the Purhepecha region of Central Mexico (Astier et al., 2005), a traditional system and a commercial one, both present in the region, were evaluated. In the Yucatan Peninsula (Moya et al., 2005), four cropping systems were evaluated, of which two were recognized as reference systems and two as alternative ones. In most cases, the alternative systems had been practiced for a relatively short period of time, ranging from two to four years.

7 Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems 413 Table 1 Main features of the analysed case studies applying the MESMIS framework Concept Description Agroecosystem Crops (4) Production objective Alternative system Spatial scale of evaluation Crops-livestock (2) Forestry (1) Agroforestry (1) Crops-livestock-forestry (7) Subsistence (7) Commercial (1) Mixed (7) Agroecological practices (soil conservation, diversification, crop association) (7) Organic (2) Resource intensification (5) Community management (1) Individual farms (5) Community (6) Evaluation team Academic (7) Cooperative/farmers organization (4) NGO (4) Farmers group (2) Mixed (2) Project impact 1 community ( families) (5) 1 community (500 families) (1) 2 10 communities ( families) (5) communities ( families) (4) Stakeholders who participated in the case studies designed, adopted and adapted management strategies as a response to the most important necessities of rural families and communities managing resources. In many cases, the strategies used to increase sustainability were based on agroecological principles. The most frequently defined strategies in the alternative systems were: Diversification through the introduction or rescue of crop and livestock species. Some examples include legumes such as velvet bean (Mucuna pruriens), bean (Phaseolus vulgaris L.), pea (Pisum sativum L.), forage species such as sorghum (Sorghum vulgare L.), ryegrass (Lolium perenne and Lolium multiflorum) and clover (Trifolium repens), forest and fruit trees and dairy cattle. Improvement measures in soil management were defined in a third of these alternative systems. These measures included: mechanical soil conservation measures (terraces and tree planting); adding organic matter in the form of cattle or green manure; practicing zero or minimum tillage; implementing crop rotation; and improving fertilization. The reduction of external inputs such as agrochemicals. In addition, methods were implemented to use both internal and external resources more efficiently. Practices such as the use of green manure and the collection and use of cattle manure in fields, as well as the use of local crop species and practices of reciprocity among peasant families (including trading of inputs, products and labour), were therefore defined. Alternative systems in these case studies had many similarities with the findings of a survey done by Pretty et al. (2003) of 208 projects (of which 45 originated from Latin America) on sustainable agricultural practices and technologies in developing countries. In addition, Tengö and Belfrage (2004) also described management strategies similar to those in our case studies, such as diversification, the use of green and cattle manure and intercropping with legumes. Across their case studies, Tengö and Belfrage (2004) found up to 45 per cent similarity between systems in regions as different as Sweden and Tanzania. This supports the strength of these strategies in the light of sustainability evaluation. The three most frequently used practices in the alternative systems relate to stability, reliability and resilience. These attributes refer directly to the conservation of the system s resource base in a changing environment. Natural, human and economic resources for the adequate functioning of agroecosystems are determined by the presence of functional and structural ecological diversity and social regulation mechanisms (Masera et al., 1999; López-Ridaura et al., 2005). The strategies developed in these case studies demonstrate the stakeholders interests in improving the systems behaviour under external shocks. The capacity of a system to cope with change has been a neglected aspect of natural resource management

8 414 M. Astier et al. (Berkes and Folke, 2002). However, strategies that address a system s behaviour in a changing environment, such as the diversification of species and economic activities, are receiving increasing attention from researchers. This focus on diversification is also seen in small-scale projects, such as the case studies described here. Diversification improves the system s capacity to cope with and respond to fluctuations in its environment; it increases system stability, reliability and resilience. It is a method generally used to reduce risks of total crop failure due to external factors such as drought, flood, pest and diseases. It has been argued that the internal regulation of functions in agroecosystems strongly depend on the amount of plant and animal biodiversity present (Altieri, 1999). Definition of indicators and comparative performance Indicators were derived from the critical points defined by the evaluation teams and reflected mainly aspects weakening system sustainability. Some similarities were found in the choice of critical points and indicators, as shown in Table 2. Productivity Most indicators measured were related to this attribute, for example yield, income and efficiency (such as cost benefit ratio). This demonstrates the importance stakeholders attach to the productivity of their systems and the important role these systems play in earning a livelihood in rural areas. Productivity indicators are also easily quantifiable. Yield was the most widely used indicator; measured in all but two case studies. Yield measurements ranged from one to five different products, depending on the importance attributed to them by the stakeholders. For example, Alemán et al. (2005), measured yields included crop, livestock and forest products. Income was another important indicator reflecting productivity. It was used in almost half the case studies, although the indicator was less diversely measured than yield. In subsistence-oriented systems, income was generally obtained from sales of produce exceeding home consumption. Systems that produced for both subsistence and commercial sales purposes usually produced only one marketable product or cash crop. As a result, only the total income or income from these cash crops was measured. The majority of the alternative systems increased values for indicators related to this attribute. Higher yields were measured in the alternative system for at least one of the products in all case studies. This is shown in Figure 2, where almost all indicators are found in the upper left half of the productivity graphs. In some case studies where yield was measured for various products, alternative management increased yields for one product, whereas yields decreased for the other product(s). Examples of this are the alternative systems in Astier et al. (2005) and Brunett et al. (2005), where forage and milk yields increased, while maize yields decreased. Due to the complexity of many agroecosystems, the simple objective of increasing income and yield can have these internal trade-offs, where the objective is reached for one product at the cost of the other one(s). Cost benefit ratios were in most cases higher or equal to those of the reference systems, and in more than half the case studies higher yields and income values were achieved at higher production costs. Alternative management resulted in increased income in all but two case studies, where this indicator was measured (Villa, 2002; Gomes de Almeida and Bianconi, 2005). However, in the latter case the income from vegetable production (with a higher value) increased, while income from milk production decreased. Stability, reliability and resilience The indicator agrodiversity was the most frequently defined one in relation to all three attributes. The concept of agrodiversity usually refers to the number of useful species/varieties in managed ecosystems, including crops, semi-domesticated plants and wild species (Brookfield, 2001). Distinctions can be made between planned diversity, which is the direct result of management, and associated diversity, an indirect one. It has been argued that the diversity of any system is not adequately represented simply by the number of species (or genotypes) present, but by the functional relationships between them in space and time (Swift et al., 2004; Jackson et al., 2007). In the case studies analysed here, agrodiversity was largely measured by a simple calculation of the number of visible or useful plant species. However, in two case studies, animal diversity was measured, and in others, two different types of diversity were measured. Measuring complete agrodiversity, including associated diversity, was in most cases beyond the scope of the evaluations and beyond the capabilities of the evaluation teams to be measured in a deeper manner (which could be done by including unplanned and belowground diversity).

9 Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems 415 Table 2 Critical points and indicators most frequently used in analysed case studies Attribute Productivity Stability, reliability and resilience Adaptability Equity Frequently defined critical points Low productivity Low income High labour intensity Monoculture Soil degradation High use of agrochemicals Presence of regulation mechanisms Low capacity to implement innovations Lack of traditional knowledge Unequal distribution of benefits Frequently used indicators Yield e.g. maize yield (kgyr 21 ; kgha 21 ), wood yield (gyr 21 ) Income e.g. net income ($yr 21 ), net income per subsystem ($yr 21 ) Efficiency e.g. cost/ benefit ratio Production costs Agro-diversity e.g. number of species Soil quality e.g. soil organic mater content (OM), nutrient contents ([N], [P], [K]) Erosion e.g. soil losses (Mgha 21 yr 21 ) Use of agrochemicals e.g. fertilizers (kgha 21 yr 21 ), pesticides (kgha 21 yr 21 ) Regulation and control mechanisms (sanctions and vigilance) enforced by social institutions for the rational use of natural resources (soil, water, grassland) Adoption rate e.g. number of farmers adopting innovations, capacity to adapt to changes Knowledge of innovation e.g. access to education, mechanisms to extend knowledge, capacity building Stakeholder involvement e.g. participation of women, men/women participation ratio, number of beneficiaries, distribution of benefits Continued Table 2 Continued Attribute Frequently defined critical points Self-reliance High dependency on external inputs Deficient organization Frequently used indicators Organizational issues e.g. level of participation in decision making, organization structure Dependence on external inputs e.g. use and costs of external inputs ($yr 21 ), level of dependency on external input (%) Agrodiversity is a complex, non-linear phenomenon, whose many mechanisms and relationships are not yet fully understood. The minimum or optimum level of diversity and optimal number of species to maintain ecosystem services remains unknown (Swift et al., 2004). However, site-specific, optimum indicator values were defined in most case studies, reflecting the highest number of useful species in a system known to the evaluation team. In five of the nine cases where agrodiversity was measured, the indicator increased for at least one of the measuring units. Diversity decreased in Astier et al. (2000) and Moya et al. (2005). However, both these case studies evaluated alternative systems that were modernized and in which diversification was not an objective. In Duarte Silveira (2005), conventional agro-forestry coffee farms showed the same value in this indicator as that of organic ones. In Gomero and Velázquez (2005), the number of agro-forestry species increased, while the number of animal species decreased. Other indicators linked to the attributes of stability, resilience and reliability included the presence of social regulation mechanisms, soil quality and soil erosion. The presence of social regulation mechanisms indicates the effective functioning of social institutions to secure the sustainable use of land. These institutions can play an important role in the use of common natural resources, by establishing and enforcing regulations or sanctions. The presence of social regulation mechanisms was seen in eight of the case studies, with six of them improving indicator values (Table 3). It is interesting to note that six cases took place with indigenous groups. It has been proven that social bonds and norms are key factors in the sustainable management of common resources (Pretty,

10 416 M. Astier et al. Figure 2 Standardized indicator values by attribute of alternative vs. reference systems 2003; Tengö and Belfrage, 2004; Ostrom, 2009) and that local governing institutions (and laws) play an important role in product extraction and the status of forests, grasslands and soil (Bluffstone et al., 2000). Results of the soil-related indicators revealed tha,t in a few case studies, soil quality improved in the alternative systems, despite having been established for a relatively short period of time. Adaptability Indicators reflecting the adaptability of systems were most commonly defined as rate of adoption and capacity building. In 11 of 15 case studies, capacity building was higher in the alternative systems than it was in the reference ones. This indicator reflects the capability of local inhabitants to implement alternative systems and to generate knowledge among farmers. Six of the alternative systems were successfully adopted by a substantial group of farmers. However, in an equal number of cases the value of this indicator decreased, highlighting the complexity of adopting alternative strategies. In Villa (2002) and Martínez (2005), the objective was to evaluate existing management systems, and therefore no attempt was made by the evaluation teams to implement alternative management strategies (Table 3). Equity This attribute was mainly evaluated through the indicator distribution of benefits among farmers. In the majority of case studies, costs and benefits were considered to be distributed in an equitable manner, ensuring both economic accessibility and cultural acceptance of proposed alternatives. However, in three cases (Astier et al., 2000; Ocampo-Fletes, 2004; Moya et al., 2005) an unequal distribution of benefits occurred in response to the prerequisites that existed for implementing modernized alternative management. For example, Ocampo-Fletes (2004)

11 Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems 417 Table 3 Qualitative changes in indicator values of alternative systems in relation to reference systems (per cent of cases, n 5 15) Self-reliance Adaptability Equity, Distribution of benefits Attribute Productivity Stability, resilience and reliability Organizational level Independence of external inputs Capacity building Rate of adoption Regulation mechanisms (sanctions) Yield Income Agro diversity Indicator/ change Increase 53 (8) 40 (6) 33 (5) 40 (6) 40 (6) 73 (11) 67 (10) 33 (5) 47 (7) Decrease 0 7 (1) 13 (2) 0 40 (6) 7 (1) 20 (3) 33 (5) 7 (1) 13 (2) 7 (1) 7 (1) (1) 7 (1) Mixed results No change 13 (2) 0 7 (1) 33 (5) 7 (1) 13 (2) 0 7 (1) 27 (4) 20 (3) 47 (7) 40 (6) 27 (4) 13 (2) 7 (1) 13 (2) 20 (3) 13 (2) Not detected reported an unequal distribution of profits within the irrigation system in Mexico, where a small group of the population obtained half the total profits from agricultural products. Self-reliance Indicators related to this attribute revealed information on the capability of a social system to respond to external changes, while maintaining its identity and values. The indicators used focused mainly on external inputs and organizational level. Indicators concerning the use, dependence or independence on external inputs were most often defined to reflect self-reliance. To avoid confusion, the term independence of external inputs was chosen to reflect both of these indicators, and data were adjusted accordingly. Fertilizers and pesticides, both organic and synthetic, were referred to as external inputs in most studies. However, in some cases the term was given a broader meaning in the form of traction use, purchased seeds and external labour costs. Astier et al. (2005) and Brunett et al. (2005) quantified the indicator in two ways, one referring to physical inputs, such as feed and fertilizers, and the other to monetary inputs, such as subsidies or institutional aid. Five alternative systems proved to be more dependent on external inputs than did their reference counterparts (Figure 2; Table 3). High investment costs and, in some cases, higher production costs were associated with the implementation of alternative management strategies. Higher labour requirements can prove particularly effective in bringing about a redistribution of benefits in areas where the labour force is underemployed (IFAD, 2005). However, high labour intensity can represent a serious limitation in many of those rural communities where the opportunity cost of local labour is very high, or where high migration rates led to labour scarcity, as in many rural communities of Mexico (Astier et al., 2005; Moya et al., 2005). Evaluation teams noted that the loss of independence on external inputs negatively influenced the adoption of alternative management strategies. In these cases, implementation costs or higher production costs were revealed to negatively influence the farmers adoption of alternatives. In one case (Martínez, 2005), production costs in the alternative system decreased with time. The organizational level improved in most of those cases where the indicator was evaluated. Institutional presence through projects can be pivotal in promoting not just alternative management strategies, but also

12 418 M. Astier et al. stronger community organization. However, it has also been found that well-organized communities are more successful in attracting external support for their projects (Brunett et al., 2005). Trade-offs in implementing alternative systems It was only in one case study (Alemán et al., 2005) that the alternative system increased all indicators selected by the evaluation team. This case study evaluated an extensive crop-livestock-forestry system (reference) and an intensified one (alternative). The main strategy in the alternative system was centred on providing high-quality forage (from agricultural residues and selected shrub species), livestock breeding and a more efficient use of manure. In all other case studies, alternative management increased some indicators at the cost of others (Table 3). The MESMIS data integration step clearly points out that trade-offs must be taken into account when considering a management change. Furthermore, it shows yet again the complexity of peasant agroecosystems and the difficulty in developing alternative management strategies that would improve the overall sustainability of a system. This step is of the utmost importance in emphasizing that no cure-all management option exists. Our interest lay in investigating the presence of common strategies in the development of alternative agricultural systems in the context of small-scale farming, as well as in that of common trade-offs. Therefore, we performed a simple trade-off analysis of the main strategy used to increase sustainability on the most commonly used indicators for productivity and stability. The relative change in yield was plotted against the relative change in agrodiversity (Figure 3). The top right corner of the graph reflects synergies (both indicators increase), whereas the top left and bottom right corner represent tradeoffs (one indicator increases at the expense of the other one). This shows that more-diverse systems were capable of being more productive than were their reference counterparts. Previous studies have also reported more efficient land use (Mäder et al., 2002) and increased productivity in multi-crop agroecosystems (Vandermeer, 1989; Amador and Gliessman, 1990; Pretty et al., 2006; Funes-Monzote et al., 2009). Viglizzo and Roberto (1998) also concluded that stability is improved by diversification in agricultural systems, whereas productivity is maintained or enhanced. The advantages of diverse systems with high agrodiversity include reduced pest damage, a more efficient use of nutrients and weed control (Francis, 1986). These advantages reduce the need for external inputs. However, in many cases, alternative management strategies increased diversity at the cost of losing the independence of external inputs. The inclusion of implementation costs as external inputs may explain this. A similar situation occurred in cases where yield was increased by alternative management, but where agrodiversity decreased. These cases include the evaluations where alternative management was a modernized system as compared to the reference system, with increased yields. Such conflicts among system s objectives, such as reducing poverty and achieving biodiversity goals, have also been reported by Hengsdijk et al. (2007). It is also interesting to observe a series of points along the vertical axis, which reflect gradual levels of increase in productivity without change in agrodiversity. General discussion The meta-analysis carried out in this study allowed us to systematize and compare case studies in a simple, yet comprehensive manner. The identified similarities in alternative strategies and trade-offs can aid future efforts by supplying hands-on information. Two issues recurred in the development and evaluation of alternative systems in various case studies. First, the explicit focus on quantifiable indicators, as suggested by the MESMIS framework, excluded many important indicators from being incorporated in the evaluation. Especially in farming systems within indigenous communities, decisions are made to satisfy non-quantifiable aspects, such as culture, selfsufficiency and food preferences, which should be taken into account in future evaluations. It should also be kept in mind that preferences of farmers for specific indicators are not taken into account in the analysis. In practice, this means that a decrease in one indicator (yield, income) vs. increase in other indicators (agrodiversity) might still cause the farmer to reject the alternative management strategy. The choice of the authors to focus this paper on the commonalities between the case studies, rather than the differences, and therefore focusing on a small group of indicators, excluded detailed information on rarely used indicators. As mentioned earlier, alternative systems were most often quite new to the region. This resulted in measurements often taken from systems still in transition,

13 Sustainability indicators, alternative strategies and trade-offs in peasant agroecosystems 419 Figure 3 Effect of diversification by alternative management (expressed by the indicator agrodiversity) on the indicators yield, independence of external inputs and income which was the case in about half of the studies analyzed, where alternative management had only been in place for less than three years and where the system had not reached a stable, dynamic state. Data collected from systems in transition will not always readily show the effects of alternative management, especially when long-term trends are being measured. This is the case of most variables or indicators measuring soil properties. Additionally, high production costs are generally seen in cases where the alternative management system is still in the initial or transitional period (Astier, 1996; Morant, 2004; IFAD, 2005). Farmers have to invest in an initial stock of new animal breeds and seeds (such as green manure or special crops), organic matter in the form of manure and hired labour for weeding (Astier, 1996; Guevara et al., 2000; Astier et al., 2005; IFAD, 2005; Martínez, 2005; Moya et al., 2005). When indicators are only measured once, these initial costs can lead to wrong conclusions. Information on the system under analysis, being either in a stable dynamic state or in a transitional state, is important for drawing conclusions on the effects of alternative management strategies on indicators. There are only two cases where the evolution of indicators related to productivity and adaptability were measured. In Astier et al. (2005), yields were measured over a four-year period, and the trend of the conventional system having a higher yield than the alternative one was maintained. However in Martínez (2005), the benefit:cost ratio and dependence of external inputs were measured in years 1, 2 and 6 after the alternative system was implemented, with an improving trend in both indicators. The process of sustainability evaluation and systems improvement is lengthy and requires long-

14 420 M. Astier et al. term sustainability evaluations including different indicator assessment during different phases (i.e. transition, stable) of the system. It is important to note that initial implementation costs demonstrate the need to support farmers in their effort to increase sustainability of their systems (e.g. Astier, 1996; Lohr and Salomonsson, 2000; Pretty et al., 2003; Morant, 2004). The single most important factor to promote more sustainable forms of agriculture is the availability of a reliable institutional support system. These systems can facilitate farmers initial access to the main components of alternative systems, which they may find difficult to reach, such as technology, funding, inputs, stocking of cattle and seeds and marketing. None of the cases revised here was part of a regional or national programme promoting sustainable agriculture. Alternative agroecosystems can be economically, environmentally and socially sustainable, but without appropriate policy support, they are condemned to remain exceptional experiences (Pretty, 2003, 2008). Conclusions and recommendations The need for more sustainable agroecosystems is an urgent one, and logical evaluation processes are required to determine the success of alternative management strategies. Such strategies, used in the case studies, were often based on agroecological principles, such as soil conservation practices and external input reduction. The most frequently used strategy was crop and product diversification. Most attention was given by the evaluation teams to the environmental and economic dimensions of sustainability. Indicators for social sustainability were less frequent in the case studies. Indicators most commonly used were yield and income, reflecting productivity; agrodiversity and presence of regulation mechanisms, related to stability, reliability and resilience. The independence of external inputs was defined as an indicator of self-reliance. In many case studies, indicators were quantified for several products, demonstrating the systems complexity and the relative importance stakeholders pay to different parts of their systems. In all but one of the case studies, some indicator values were increased at the costs of others by alternative management. This clearly demonstrated the difficulty in developing more sustainable agroecosystems. Most alternative farming systems showed the ability to increase agro-diversity and at least one of the defined yield and income indicators. Aspects that limited sustainability were related to adaptability and self-reliance, as some alternative systems presented a higher dependency on external inputs (which was correlated with higher investment costs). In more than half of the case studies, higher yields or income were achieved at the expense of higher production costs. Professionals from the evaluation teams mentioned that this phenomenon constrained the adoption of alternative systems. Nevertheless, these were implemented by influential groups of farmers in almost half the case studies. The alternative systems that were evaluated were relatively new for almost all case studies, meaning that they were still in a transitional stage. This fact underlines the importance of long-term efforts in sustainability evaluation. Information on the estimated time length of transition, and the associated investment costs, is essential for farmers who are interested in adopting new management strategies. Analysing case studies through standardized indicator values was useful in detecting trade-offs and synergies in comparative systems analyses. This type of efforts, guided by a framework such as MESMIS, proved to improve knowledge on agroecosystem performance, which can aid decisionmaking among stakeholders. This study will aid future efforts towards sustainability evaluation in peasant agroecosystems, by providing information on the type of indicators selected, the performance of alternative resource management systems and the common strategies and trade-offs in pursuing sustainability. Acknowledgements This study is part of the larger MESMIS programme, under the project Evaluación de Sustentabilidad de Sistemas Complejos Socio-Ambientales, ECOSUR- UNAM-GIRA ( ), financed by the Mexican Council for Science and Technology (CONACYT, grant 02464). We would like to thank Amy E. Snively for her constructive comments on the manuscript. The authors express their gratitude to all farmers and researchers that used the MESMIS framework, and who shared with us their documents and experiences.

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