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971.
Most accounts of the effect of the global marketplace on deforestation in Africa, Asia, and Latin America emphasize the demand for timber used in industrial processes and the conversion of tropical forests to pastures for beef cattle. In recent years, numerous scholars and policymakers have suggested that developing a market for non-timber forest products (NTFPs) might slow the pace of habitat destruction. Although increased demand for NTFPs rarely results in massive deforestation, the depletion of the raw materials needed to make particular products is common. Many rural households in the Mexican state of Oaxaca have prospered over the past three decades through the sale of brightly-painted, whimsical wood carvings (alebrijes) to international tourists and the owners of ethnic arts shops in the United States, Canada, and Europe. This paper examines a promising project aimed at providing Oaxacan alebrije-makers with a reliable, legal, and sustainable supply of wood. The ecologists, artisans, merchants, and forest owners involved in the project face formidable obstacles. Gaining permission to harvest wood from land belonging to Oaxacan communities requires the negotiation of a complex social, legal, economic, and political landscape. Artisans’ decisions about where to obtain wood rest largely on price, quality, and reliability of the supplier; they are willing to pay a premium for ecologically sustainable wood only if the additional cost can be passed on to consumers. Nonetheless, a group of carvers has begun to buy sustainably harvested wood. This arrangement has economic advantages for both the alebrije-makers and the owners of the forests where the wood is produced. Michael Chibnik is Professor of Anthropology at the University of Iowa. He has conducted fieldwork in Belize, Peru, Mexico, and in various parts of the United States. His research interests include economic anthropology, artisans, work organization, agricultural decision-making, and political ecology. He is the author of Crafting Tradition: The Making and Marketing of Oaxacan Wood Carvings (University of Texas Press, 2003) and Risky Rivers: The Economics and Politics of Floodplain Farming in Amazonia (University of Arizona Press, 1994), and editor of Farm Work and Fieldwork: American Agriculture in Anthropological Perspective (Cornell University Press, 1987). Dr. Silvia E. Purata is a Mexican ethnoecologist based in Xalapa, Veracruz. She is a member of People and Plants International, an organization that works to integrate conservation and the use of natural resources. Purata has conducted research on the methods indigenous peoples use to extract non-timber forest products (NTFPs) in tropical forests and the fate of such systems in varying socioeconomic circumstances. She has also been working on the promotion of forest certification in the Selva Maya.  相似文献   
972.
Contemporary regulation of food safety incorporates principles of quality management and systemic performance objectives that used to characterize private standards. Conversely, private standards are covering ground that used to be the realm of regulation. The nature of the two is becoming increasingly indistinguishable. The case study of the Ugandan fish export industry highlights how management methods borrowed from private standards can be applied to public regulation to achieve seemingly conflicting objectives. In the late 1990s, the EU imposed repeated bans on fish imported from Uganda on the basis of food safety concerns. However, the EU did not provide scientific proof that the fish were actually “unsafe.” Rather, the poor performance of Uganda’s regulatory and monitoring system was used as justification. Only by fixing “the system” (of regulations and inspections) and performing the ritual of laboratory testing for all consignments for export to the EU did the Ugandan industry regain its status as a “safe” source of fish. Yet, gaps and inconsistencies abound in the current Ugandan fish safety management system. Some operations are by necessity carried out as “rituals of verification.” Given the importance of microbiological tests and laboratories in the compliance system, “alchemic rituals” provide an appropriate metaphor. These rituals are part and parcel of a model that reassures the EU fish-eating public that all is under control in Uganda from boat to point of export. As a consequence, actual non-compliance from boat to landing site allows the fishery to survive as an artisanal operation. Stefano Ponte is Senior Researcher at the Danish Institute for International Studies, Copenhagen. His research focuses on the role of standards, regulation and quality conventions in the governance of agro-food value chains, with particular focus on Africa. He is co-author of Trading Down: Africa, Value Chains and the Global Economy and The Coffee Paradox: Global Markets, Commodity Trade and the Elusive Promise of Development.  相似文献   
973.
We examine changing production relations in the Mexican tequila industry to explore the ways in which large industrial firms are using “reverse leasing arrangements,” a form of contract farming, to extend their control over small agave farmers. Under these arrangements, smallholders rent their parcels to contracting companies who bring in capital, machinery, labor, and other agricultural inputs. Smallholders do not have access to their land, nor do they make any of the management decisions. We analyze the factors that have led some producers to participate in reverse leasing arrangements, while allowing other producers to continue farming independently. In addition, we look at the ways in which farmers are responding to these new production relations and constraints and the strategies that they are using to regain control over the production process.
Sarah BowenEmail:
  相似文献   
974.
Food quality is an important issue on the global agenda, particularly in high- and middle-income economies, but of little concern in designing Mexico’s food policy. Food policy has focused on quantity and in the case of maize, on satisfying domestic demand by supporting large commercial agriculture and importing from abroad. However, and as argued in this paper, obtaining a food staple (maize-tortilla) of quality is also an important issue for rural households and contributes to motivating continued smallholder production. Based on case studies in the rural district of Atlacomulco, in the state of Mexico, as well as in two regions of the state of Chiapas, this paper analyzes the production and consumption strategies of rural households. We focus on goals of food security and quality and note differential trends among households of varying characteristics and local contexts. We find that the motivation of small-scale producers to grow maize should be supported by Mexico’s food policy.  相似文献   
975.
This study reports on action research efforts that were aimed at developing institutional arrangements beneficial for soil fertility improvement. Three stages of action research are described and analyzed. We initially began by bringing stakeholders together in a platform to engage in a collaborative design of new arrangements. However, this effort was stymied mainly because conditions conducive for learning and negotiation were lacking. We then proceeded to support experimentation with alternative arrangements initiated by individual landowners and migrant farmers. The implementation of these arrangements too ran into difficulties due to intra-family dynamics and ambiguities regarding land tenure. Further investigations to find out how ambiguities could be tackled revealed that the local actors themselves had taken initiatives towards developing institutional innovations to reduce ambiguities. However, there is still considerable scope for further development of these self-organized innovations. The article ends with a reflection on inter-disciplinary action research, where it is argued that making “mistakes” is an inherent and necessary characteristic in action research that aims to address complex social issues.
Samuel Adjei-NsiahEmail:
  相似文献   
976.
The reaction to conventional agriculture and food systems has generated a host of alternative social movements in the past several decades. Many progressive agrifood researchers have researched these movements, exploring their strengths, weaknesses, and failures. Most such research is abstracted from the movements themselves. This paper proposes a new way of self-organization that, while fulfilling traditional university demands on researchers, will provide research support for progressive agrifood movements by transcending the boundaries of disciplines and individual universities.
William H. FriedlandEmail:

William H. Friedland   is Professor Emeritus at the University of California, Santa Cruz where his research continues on commodity systems, wine and grapes, the globalization of agriculture and food, and exploring ways to strengthen alternative social movements to subvert the dominant paradigm.  相似文献   
977.
Within-field variations in potential grain yield may be due to variations in plant available soil water. Different water holding capacities affect yield differently in different years depending on weather. By estimating plant-water availability in different weathers, scenarios could be created of how yield potential and thereby fertilizer demand may vary within fields. To test this, measured cereal grain yields from a dry, a wet and an intermediate year were compared with different soil moisture related variables in a Swedish arable field consisting of clayey and sandy areas. Soil water budget calculations based on weather data and maximum plant available water (PAW), estimated from soil type and rooting data, were used to assess drought. A reasonable correlation between estimated and measured soil moisture was achieved. In the dry year, drought days explained differences in yield between the clayey and the sandy soil, but yield was better explained directly by maximum PAW, elevation, clay content and soil electrical conductivity (SEC). Yield correlated significantly with SEC and elevation within the sandy soil in the dry year and within the clayey soil in the wet year, probably due to water and nitrogen limitation respectively. Dense SEC, elevation and yield data were therefore used to divide the field into management zones representing different risk levels for drought and waterlogging. These could be used as a decision support tool for site-specific N fertilization, since both drought and waterlogging affect N fertilization demand.  相似文献   
978.
Genomic imprinting causes parental origin-specific monoallelic gene expression through differential DNA methylation established in the parental germ line. However, the mechanisms underlying how specific sequences are selectively methylated are not fully understood. We have found that the components of the PIWI-interacting RNA (piRNA) pathway are required for de novo methylation of the differentially methylated region (DMR) of the imprinted mouse Rasgrf1 locus, but not other paternally imprinted loci. A retrotransposon sequence within a noncoding RNA spanning the DMR was targeted by piRNAs generated from a different locus. A direct repeat in the DMR, which is required for the methylation and imprinting of Rasgrf1, served as a promoter for this RNA. We propose a model in which piRNAs and a target RNA direct the sequence-specific methylation of Rasgrf1.  相似文献   
979.
Degenerative disorders of motor neurons include a range of progressive fatal diseases such as amyotrophic lateral sclerosis (ALS), spinal-bulbar muscular atrophy (SBMA), and spinal muscular atrophy (SMA). Although the causative genetic alterations are known for some cases, the molecular basis of many SMA and SBMA-like syndromes and most ALS cases is unknown. Here we show that missense point mutations in the cytoplasmic dynein heavy chain result in progressive motor neuron degeneration in heterozygous mice, and in homozygotes this is accompanied by the formation of Lewy-like inclusion bodies, thus resembling key features of human pathology. These mutations exclusively perturb neuron-specific functions of dynein.  相似文献   
980.
An artificial crystal structure has been fabricated exhibiting a full three-dimensional photonic bandgap effect at optical communication wavelengths. The photonic crystal was constructed by stacking 0.7-micrometer period semiconductor stripes with the accuracy of 30 nanometers by advanced wafer-fusion technique. A bandgap effect of more than 40 decibels (which corresponds to 99.99% reflection) was successfully achieved. The result encourages us to create an ultra-small optical integrated circuit including a three-dimensional photonic crystal waveguide with a sharp bend.  相似文献   
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