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Agricultural Production (agricultural + production)
Selected AbstractsThe Exploitation of Crop Allelopathy in Sustainable Agricultural ProductionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2005T. D. Khanh Abstract Crop allelopathy may be useful to minimize serious problems in the present agricultural production such as environmental pollution, unsafe products, human health concerns, depletion of crop diversity, soil sickness and reduction of crop productivity. Several crops including alfalfa, buckwheat, maize, rice, rye, sorghum, sunflower, wheat, etc. are affected either by their own toxicity or phytotoxin exudates when their residues decompose in the soil, that show strong suppression on weed emergences. Allelopathic crops when used as cover crop, mulch, smother crops, green manures, or grown in rotational sequences are helpful in reducing noxious weeds and plant pathogen, improve soil quality and crop yield. Those crop plants, particularly the legumes, incorporated at 1,2 tons ha,1 (alfalfa, buckwheat, rice by-products), which can give weed reduction and increase of rice yield by 70 and 20 %, respectively, are suggested for use as natural herbicides. Allelochemicals from allelopathic crops may aid in the development of biological herbicides and pesticides. Cultivating a system with allelopathic crops plays an important role in the establishment of sustainable agriculture. The introduction of allelopathic traits from accessions with strong allelopathic potential to the target crops will enhance the efficacy of crop allelopathy in future agricultural production. [source] Agricultural and Rural Development in China: Achievements and Challenges Entwicklung der Landwirtschaft und des ländlichen Raums in China: Erfolge und Herausforderungen Le développement agricole et rural en Chine : résultats et défisEUROCHOICES, Issue 2 2009Chen Xiaohua Summary Agricultural and Rural Development in China: Achievements and Challenges China has made great advances in its agricultural and rural development since the reforms and opening-up that began in 1978. It has not only fed its population of 1.3 billion, but has also contributed to international agricultural development and food security. Agricultural production registered great development, providing sufficient food and clothes for 21 per cent of the world's population with 9 per cent of the arable land. In the process farmers' living standards improved remarkably and rural public utilities and services were greatly enhanced. China is now in a key transition period of accelerating the transformation and modernisation of traditional agriculture and rural society. It is facing significant challenges. Agriculture is still one of the weakest industries in China and it is proving difficult to sustain increases in grain output and farmers' incomes. The problems of uneven development in rural areas have become increasingly prominent and the gap between urban and rural development is tending to widen. The Chinese government will respond strategically to these challenges and will firmly pursue the construction of a new efficient and sustainable socialist countryside, along the path of modernisation with Chinese characteristics. It will also make greater contributions to world agriculture and rural development. Les progrès de la Chine en termes de développement agricole et rural depuis le début des réformes et l'ouverture en 1978 ont été considérables. Non seulement le pays a nourrit une population de 1.3 millions d'habitants mais il a contribué au développement et à la sécurité alimentaire au niveau international. La production agricole a fortement augmenté et a fournit suffisamment de nourriture et de vêtements à 21 pour cent de la population du monde avec 9 pour cent des terres cultivables. Ce processus s'est accompagné d'une hausse considérable du niveau de vie des agriculteurs et d'une grande amélioration des services publics dans les zones rurales. La Chine est maintenant à un moment clé de sa période de transition, caractérisé par une accélération de la transformation et de la modernisation de l'agriculture et de la société rurale traditionnelles. Des défis importants se présentent à elle. L'agriculture reste une des industries chinoises les plus fragiles et il se révèle difficile de continuer à augmenter la production céréalière et les revenus des agriculteurs. Les problèmes d'inégalité de développement dans les zones rurales deviennent de plus en plus visibles et l'écart de développement entre les zones urbaines et les zones rurale tend à s'accroître. Les pouvoirs publics chinois vont apporter une réponse stratégique à ces défis et vont poursuivre fermement la construction d'une nouvelle campagne socialiste efficace et durable, en suivant une voie de modernisation typiquement chinoise. Ils vont aussi accroître les contributions de la Chine au développement agricole et rural mondial. Seit Beginn der Reformen und der Öffnungspolitik 1978 hat sich Chinas Landwirtschaft und ländlicher Raum enorm weiterentwickelt. China hat seitdem nicht nur seine 1.3 Milliarden Einwohner ernährt, sondern auch zur internationalen Agrarentwicklung und Ernährungssicherung beigetragen. Die Agrarproduktion wurde erheblich ausgeweitet und deckt nun 21 Prozent des weltweiten Bedarfs an Lebensmitteln und Kleidung bei gerade einmal 9 Prozent der Weltackerfläche. Dabei haben sich die Lebensbedingungen für die Landwirte sowie das Angebot an öffentlichen Einrichtungen und Dienstleistungen im ländlichen Raum deutlich verbessert. China durchläuft gerade eine wichtige Übergangsphase, in der sich der Wandel und die Modernisierung der traditionellen Landwirtschaft und der Landbevölkerung noch schneller vollziehen, und steht großen Herausforderungen gegenüber. Die Landwirtschaft ist nach wie vor einer der schwächsten Sektoren in China, und es erweist sich als schwierig, die Steigerungsraten bei der Getreideerzeugung und den Einkommen in der Landwirtschaft aufrecht zu erhalten. Die Probleme der ungleichmäßigen Entwicklung in ländlichen Gebieten werden immer offensichtlicher, und die Kluft zwischen städtischer und ländlicher Entwicklung droht sich auszuweiten. Die chinesische Regierung wird diesen Herausforderungen strategisch begegnen und , ganz im Sinne einer Modernisierung mit chinesischen Merkmalen , daran festhalten, einen neuen sozialistischen ländlichen Raum effizient und nachhaltig zu gestalten. Sie wird ebenfalls einen noch größeren Beitrag zur Weltlandwirtschaft und zur Entwicklung des ländlichen Raums leisten. [source] Is off-farm income reforming the farm?AGRICULTURAL ECONOMICS, Issue 2 2009Evidence from Mexico Agricultural production; Household models; Off-farm income; Rural Mexico Abstract Does access to off-farm income complement or compete with agricultural production? This article explores the effect of off-farm income on agricultural production activities, using data from the 2003 Mexico National Rural Household Survey. We first discuss the theoretical conditions under which access to off-farm income may influence production in an agricultural household model. Instrumental-variable (IV) estimation methods are then used to test whether agricultural production activities, technologies, and input use differ between households with and without access to off-farm income. We find that off-farm income has a negative effect on agricultural output and the use of family labor on the farm, but a positive impact on the demand for purchased inputs. There is also a slight efficiency gain in households with access to off-farm income. Findings offer insights into how household production evolves as rural households increasingly engage in off-farm income activities. [source] Economic transition and the decline of agricultural production in EstoniaJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 4 2005Shujie Yao Agricultural production in Estonia has declined rapidly under economic transition since 1992, causing a number of undesirable social and economic problems. Rural unemployment has increased, so has the incidence of poverty. The country has changed from being a net exporter to a net importer of many major agricultural products over a short period of time. To understand the causes of agricultural decline, this paper uses a policy analysis matrix (PAM) to study the competitiveness and profitability of various agricultural, fishery and forest products for the period 1994,95. The results suggest that much of the loss of production may have been explained by economic reforms that were intended to eradicate market distortions created by the former Soviet system, but government's ,non-interventionist' policy and the rigidity of foreign exchange rate may have aggravated the situation. Copyright © 2005 John Wiley & Sons, Ltd. [source] NATURE, MARKETS AND STATE RESPONSE: THE DROUGHT OF 1939 IN JAPAN AND KOREAAUSTRALIAN ECONOMIC HISTORY REVIEW, Issue 1 2010Janet Hunter drought; hydroelectricity; Japan; Korea; rice production Large areas of Northeast Asia experienced drought in 1939. Agricultural production in Korea decreased significantly, but the drought did not cause famine in Japan despite its dependence on rice imports from Korea. The paper analyses the impact of the 1939 drought on the markets for rice and electricity in Japan. The authorities were ill-prepared for such a disaster but willing to use it for the purpose of covering for other problems. The drought thus accelerated the move of Japan's economic system towards a managed economy. A lower total rainfall in Japan in 1940 did not generate similar problems, suggesting that the broader political, economic, and social context is crucial to the identification of short-term climatic fluctuations as crises. [source] The Origins and Influence of Land Property Rights in VietnamDEVELOPMENT POLICY REVIEW, Issue 3 2008Denise Hare Vietnam's 1993 Land Law was intended not only to increase the security of farmers'usage rights to their land, but also to facilitate land transfers. Despite potential benefits, the actual issuance of land-use rights certificates to farmers (as specified by the law) proceeded rather slowly in some regions. This article seeks to identify factors that explain the emergence of this form of property right as well as to measure its effect on agricultural production. The results suggest that the certificate's direct contribution may be rather small in the absence of the appropriate supporting conditions and institutions. [source] Pigs, presses and pastoralism: farming in the fifth to sixth centuries ADEARLY MEDIEVAL EUROPE, Issue 1 2009Tamara Lewit The fifth to sixth centuries were a time of significant change in rural settlement, land use, production levels and productive technology in many regions. Archaeological and related discoveries suggest that in western Europe, specialized market- and state-oriented production gave way to mixed animal husbandry and diversified farming more suited to local terrains. This was accompanied by a widespread transformation of rural settlement. In contrast, the eastern Mediterranean experienced rural settlement expansion, intensification of land use, increased market-oriented agricultural production, and a significant change in oil and wine press technology. These changes seem to reflect the socio-political context in both east and west during this pivotal period. [source] HIGH COTTON: WHY THE USA SHOULD NOT PROVIDE SUBSIDIES TO COTTON FARMERSECONOMIC AFFAIRS, Issue 2 2008Madeline Helling Trade theorists agree that barriers to trade are declining. Still more progress could be made if trade barriers and government interventions were eliminated. One area in which government interference can and should be vastly reduced is that of agricultural production in general and US cotton production in particular. [source] Progress, decline, growth: product and productivity in Italian agriculture, 1000,2000ECONOMIC HISTORY REVIEW, Issue 3 2004GIOVANNI FEDERICO This article estimates agricultural production and output per worker in Italy, from about the year 1000 to the present. The millennium may be divided neatly into three periods. Output per worker increased until the fourteenth century, declined, with some fluctuations, until the end of the nineteenth century, and then recovered, booming in the past 50 years. [source] Systemic design of a productive chain: Reusing coffee waste as an input to agricultural productionENVIRONMENTAL QUALITY MANAGEMENT, Issue 3 2010Silvia Barbero First page of article [source] Vegetated agricultural drainage ditches for the mitigation of pyrethroid-associated runoffENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2005Erin R. Bennett Abstract Drainage ditches are indispensable components of the agricultural production landscape. A benefit of these ditches is contaminant mitigation of agricultural storm runoff. This study determined bifenthrin and lambda-cyhalothrin (two pyrethroid insecticides) partitioning and retention in ditch water, sediment, and plant material as well as estimated necessary ditch length required for effective mitigation. A controlled-release runoff simulation was conducted on a 650-m vegetated drainage ditch in the Mississippi Delta, USA. Bifenthrin and lambda-cyhalothrin were released into the ditch in a water-sediment slurry. Samples of water, sediment, and plants were collected and analyzed for pyrethroid concentrations. Three hours following runoff initiation, inlet bifenthrin and lambda-cyhalothrin water concentrations ranged from 666 and 374 ,g/L, respectively, to 7.24 and 5.23 ,g/L at 200 m downstream. No chemical residues were detected at the 400-m sampling site. A similar trend was observed throughout the first 7 d of the study where water concentrations were elevated at the front end of the ditch (0,25 m) and greatly reduced by the 400-m sampling site. Regression formulas predicted that bifenthrin and lambda-cyhalothrin concentrations in ditch water were reduced to 0.1% of the initial value within 280 m. Mass balance calculations determined that ditch plants were the major sink and/or sorption site responsible for the rapid aqueous pyrethroid dissipation. By incorporating vegetated drainage ditches into a watershed management program, agriculture can continue to decrease potential non-point source threats to downstream aquatic receiving systems. Overall results of this study illustrate that aquatic macrophytes play an important role in the retention and distribution of pyrethroids in vegetated agricultural drainage ditches. [source] Evolutionary response of landraces to climate change in centers of crop diversityEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 5-6 2010Kristin L. Mercer Abstract Landraces cultivated in centers of crop diversity result from past and contemporary patterns of natural and farmer-mediated evolutionary forces. Successful in situ conservation of crop genetic resources depends on continuity of these evolutionary processes. Climate change is projected to affect agricultural production, yet analyses of impacts on in situ conservation of crop genetic diversity and farmers who conserve it have been absent. How will crop landraces respond to alterations in climate? We review the roles that phenotypic plasticity, evolution, and gene flow might play in sustaining production, although we might expect erosion of genetic diversity if landrace populations or entire races lose productivity. For example, highland maize landraces in southern Mexico do not express the plasticity necessary to sustain productivity under climate change, but may evolve in response to altered conditions. The outcome for any given crop in a given region will depend on the distribution of genetic variation that affects fitness and patterns of climate change. Understanding patterns of neutral and adaptive diversity from the population to the landscape scale is essential to clarify how landraces conserved in situ will continue to evolve and how to minimize genetic erosion of this essential natural resource. [source] Multiple stressors and regime shifts in shallow aquatic ecosystems in antipodean landscapesFRESHWATER BIOLOGY, Issue 2010JENNY DAVIS Summary 1. Changes in land management (land use and land cover) and water management (including extraction of ground water and diversion of surface waters for irrigation) driven by increases in agricultural production and urban expansion (and fundamentally by population growth) have created multiple stressors on global freshwater ecosystems that we can no longer ignore. 2. The development and testing of conceptual ecological models that examine the impact of stressors on aquatic ecosystems, and recognise that responses may be nonlinear, is now essential for identifying critical processes and predicting changes, particularly the possibility of catastrophic regime shifts or ,ecological surprises'. 3. Models depicting gradual ecological change and three types of regime shift (simple thresholds, hysteresis and irreversible changes) were examined in the context of shallow inland aquatic ecosystems (wetlands, shallow lakes and temporary river pools) in southwestern Australia subject to multiple anthropogenic impacts (hydrological change, eutrophication, salinisation and acidification). 4. Changes in hydrological processes, particularly the balance between groundwater-dominated versus surface water-dominated inputs and a change from seasonal to permanent water regimes appeared to be the major drivers influencing ecological regime change and the impacts of eutrophication and acidification (in urban systems) and salinisation and acidification (in agricultural systems). 5. In the absence of hydrological change, urban wetlands undergoing eutrophication and agricultural wetlands experiencing salinisation appeared to fit threshold models. Models encompassing alternative regimes and hysteresis appeared to be applicable where a change from a seasonal to permanent hydrological regime had occurred. 6. Irreversible ecological change has potentially occurred in agricultural landscapes because the external economic driver, agricultural productivity, persists independently of the impact on aquatic ecosystems. 7. Thematic implications: multiple stressors can create multiple thresholds that may act in a hierarchical fashion in shallow, lentic systems. The resulting regime shifts may follow different models and trajectories of recovery. Challenges for ecosystem managers and researchers include determining how close a system may be to critical thresholds and which processes are essential to maintaining or restoring the system. This requires an understanding of both external drivers and internal ecosystem dynamics, and the interactions between them, at appropriate spatial and temporal scales. [source] Interpreting the Viking Age to Medieval period transition in Norse Orkney through cultural soil and sediment analysesGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 4 2005Ian A. Simpson The transition from the Viking Age (ca. A.D. 800,1050) to the Medieval period (ca. A.D. 1050,1500) saw the development of widening trade activities that incorporated peripheral North Atlantic polities into mainstream Europe and contributed to the intensification of marineresource exploitation and agricultural production in these localities. As yet, there is only limited understanding of these intensification processes and their interrelationships, particularly at a local, site-based level. Through the micromorphological analysis of cultural soils and sediments at Quoygrew, Westray, Orkney, we explore the characteristics of farming and fishing activity during the Viking Age,Medieval transition period and establish their chronological relationships. The study demonstrates: (1) that intensification took place from ca. A.D. 966,1162 on an already existing Viking Age settlement, (2) that intensification of fishing activity occurred prior to the intensification of arable agriculture, and (3) that the Quoygrew site continued throughout this period as an economically diverse permanent settlement. When viewed in a wider North Atlantic context, these findings indicate that intensification of different economic activities proceeded at different rates and that intensification of specialized economic activities during the transition from the Viking Age to the Medieval period was dependent on existing knowledge of local environments. © 2005 Wiley Periodicals, Inc. [source] Late prehistoric soil fertility, irrigation management, and agricultural production in northwest coastal PeruGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 1 2004Lee Nordt The Pampa de Chaparrí (Pampa) in hyperarid northwest coastal Peru is an ideal area to study late prehispanic agricultural technology and production because irrigation canals and furrowed fields have been preserved since abandonment approximately 500 years ago. We collected 55 samples for soil characterization, fertility, and micromorphic analyses and compared these results to a noncultivated control soil previously sampled in an adjacent valley. Natural soil fertility levels for maize, cotton, and bean production were generally high during late prehispanic cultivation in the Pampa. Maintaining adequate nitrogren levels for production, however, would have required external inputs from livestock manure, guano, or leguminous plants. The management of low soil salinity levels was possible because of rapidly permeable soils and irrigation waters low in salt. Based on available water capacity and climate conditions, the Blaney-Criddle Equation yields evapotranspiration rates indicating that irrigation frequency was necessary in a range of every 10,16 days during the growing season. © 2004 Wiley Periodicals, Inc. [source] A past and a future for diversification on farms?GEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 1 2003Some evidence from large-scale, commercial farms in South East England Abstract Diversification has been identified as a common response to the agricultural crisis of the 1980s and to the changing ethos of agricultural policy in the closing decade of the twentieth century. In particular, farmers operating large-scale farms have been prominent in adopting this approach, just as they were innovative across a range of farming practices in the expansion and modernisation of their agricultural production in earlier decades. Can we identify serial diversifiers within this sector of the farming community, who are disposed to react in an entrepreneurial fashion to the changing fortunes of agriculture? The paper draws on results from a survey of large-scale commercial farmers in South East England and, by examining the sequence in which various forms of diversification were adopted, identifies a temporal pattern as farmers responded to the fluctuating fortunes of the agricultural industry over the past thirty years. But has the potential for diversification been exhausted? The paper also considers future prospects for diversification within the large-scale, commercially oriented sector of the agricultural industry. [source] Youth, AIDS and Rural Livelihoods in Southern AfricaGEOGRAPHY COMPASS (ELECTRONIC), Issue 3 2008Lorraine Van Blerk AIDS, in interaction with other factors, is impacting on the livelihood activities, opportunities and choices of young people in southern Africa. This article explores these linkages firstly by reviewing what is known about the impacts of AIDS on young people, before looking more specifically at how this impinges on their future ability to secure livelihoods. Within the home and family, AIDS often results in youth taking on a heavy burden of responsibilities. This can include caring for sick relatives, helping with chores and taking on paid employment. This burden of care and work can have further impacts on young people's future livelihoods as they find they have reduced access to schooling, potential loss of inheritance and a breakdown in the intergenerational transfer of knowledge, which is especially important for sustained agricultural production. The article ends by suggesting that the sustainable livelihoods approach can be useful for understanding the complexity of the issues surrounding the impacts of AIDS on young people's livelihoods and calls for further research to explore how their access to future sustainable livelihoods in rural southern Africa might be supported. [source] The grassland farming system and sustainable agricultural development in ChinaGRASSLAND SCIENCE, Issue 1 2005Zhibiao Nan Abstract Grassland is the largest terrestrial ecosystem in China, at about 39 280 × 104 ha and covers 41% of the total land area. Grasslands not only provide forage to feed livestock, but also play a critical role in alleviating many of the most challenging environmental and ecological problems that humankind is facing. About 90% of the total usable grassland in China has been degraded to various extents and this is the number one problem facing agricultural production, rural development and environmental improvement. Research on grassland degradation has been carried out since the early 1950s. Enormous achievements have been made and theory and a technical system for pastoral agriculture have been developed. This pastoral agriculture system is a well-organized modern farming system including four production levels, that is, preplant, plant, animal and postbiotic levels, and is linked by three interfaces, including vegetation-site, grassland-animal and production-management. The system capacity and productivity could be improved by system coupling. Since it emerged, this pastoral agriculture system has been established in various ecological regions in China and significant improvements in agricultural sustainability, farmer's income and environmental stability have been obtained. In the future, it will play a more critical role in developing sustainable agriculture in China. [source] Aquifer Sensitivity to Pesticide Leaching: Testing a Soils and Hydrogeologic Index MethodGROUND WATER MONITORING & REMEDIATION, Issue 4 2005Edward Mehnert For years, researchers have sought index and other methods to predict aquifer sensitivity and vulnerability to nonpoint pesticide contamination. In 1995, an index method and map were developed to define aquifer sensitivity to pesticide leaching based on a combination of soil and hydrogeologic factors. The soil factor incorporated three soil properties: hydraulic conductivity, amount of organic matter within individual soil layers, and drainage class. These properties were obtained from a digital soil association map. The hydrogeologic factor was depth to uppermost aquifer material. To test this index method, a shallow ground water monitoring well network was designed, installed, and sampled in Illinois. The monitoring wells had a median depth of 7.6 m and were located adjacent to corn and soybean fields where the only known sources of pesticides were those used in normal agricultural production. From September 1998 through February 2001, 159 monitoring wells were sampled for 14 pesticides but no pesticide metabolites. Samples were collected and analyzed to assess the distribution of pesticide occurrence across three units of aquifer sensitivity. Pesticides were detected in 18% of all samples and nearly uniformly from samples from the three units of aquifer sensitivity. The new index method did not predict pesticide occurrence because occurrence was not dependent on the combined soil and hydrogeologic factors. However, pesticide occurrence was dependent on the tested hydrogeologic factor and was three times higher in areas where the depth to the uppermost aquifer was <6 m than in areas where the depth to the uppermost aquifer was 6 to <15 m. [source] Technology and the World the Slaves MadeHISTORY COMPASS (ELECTRONIC), Issue 2 2006Robert Gudmestad The study of American slavery is a crowded field and each year the historical profession witnesses the publication of several new books. Despite this steady onslaught of scholarship, significant gaps remain in our understanding of slavery and its influence on the South. One area that has lacked sustained attention is the nexus of slavery and technological development. Several new books demonstrate that changes in technology profoundly altered the lives and labor of slaves. Historians have approached the presence of technology in a slave society from several different traditions. Some scholars argued that plantation development and mechanical progress were difficult to wed together, while others noted the progressive nature of southern agricultural production, but discussions of white attitudes and behavior overshadowed the effects of machinery on the lives of slaves. An innovative approach has emphasized the employment of slaves in factories, but such works have done little to provide insight into how technological innovation influenced plantation slaves. Several new studies have reversed these trends and promise to lead us in important directions. Examinations of the cotton gin, steamboats, sugar plantations, and clocks have revealed that technology brought enormous change to the bulk of slaves, not just those living in urban areas or working in factories. Patterns and practices of work, opportunities for autonomy, and time away from the master's unstinting gaze, all changed because of mechanical innovation. Taken together, these new works also provide clues to the making and remaking of the southern economy and society. [source] Current status and prospects of agricultural drainage in China,IRRIGATION AND DRAINAGE, Issue S1 2007Wang Shaoli engorgement; salinisé alcalinisé; drainage agricole; environnement de l'eau Abstract Waterlogged and saline,alkali-affected soils are the main restrictions for agricultural production in many regions in China. Great efforts have been expended to conduct research on how to reclaim waterlogged and saline, alkali-affected soils for sustained agricultural productivity. Long-term practices have proved that agricultural drainage can be used to reduce the incidence of waterlogging and saline,alkali soil problems, as well as reclaim waterlogged and saline,alkali-affected soils, thus enhancing and sustaining agricultural productivity and national economic development. This paper describes the importance of agricultural drainage technology in China, reviews the current status of drainage technology, summarizing existing problems, and making some comparisons of drainage technologies from China and the USA. Future research needs in drainage technology for China are proposed. Copyright © 2007 John Wiley & Sons, Ltd. Les sols engorgés et salinisés ou alcalinisés sont les principaux freins à la production agricole dans de nombreuses régions de Chine. De grands efforts de recherche ont été déployés sur la façon de les récupérer pour améliorer la productivité agricole. Des pratiques de longue date ont montré que le drainage agricole peut être utilisé pour réduire l'incidence des problèmes posés par ces sols et pour les récupérer, favorisant de ce fait la productivité agricole et le développement économique national. Cet article décrit l'importance de la technologie du drainage agricole en Chine et passe en revue son état actuel, récapitulant les problèmes existants et comparant le drainage en Chine et aux Etats-Unis, pour terminer en proposant des efforts de recherche encore plus poussés en Chine. Copyright © 2007 John Wiley & Sons, Ltd. [source] Irrigation and drainage systems research and development in the 21st century,IRRIGATION AND DRAINAGE, Issue 4 2002Bart Schultz irrigation; drainage; développement durable; système de réseau Abstract One critical problem confronting mankind today is how to manage the intensifying competition for water between expanding urban centres, traditional agricultural activities and in-stream water uses dictated by environmental concerns. In the agricultural sector, the dwindling number of economically attractive sites for large-scale irrigation and drainage projects limits the prospects of increasing the gross cultivated area. Therefore, the required increase in agricultural production will necessarily rely largely on a more accurate estimation of crop water requirements on the one hand, and on major improvements in the construction, operation, management and performance of existing irrigation and drainage systems, on the other. The failings of present systems and the inability to sustainably exploit surface and groundwater resources can be attributed essentially to poor planning, design, system management and development. This is partly due to the inability of engineers, planners and managers to adequately quantify the effects of irrigation and drainage projects on water resources and to use these effects as guidelines for improving technology, design and management. To take full advantage of investments in agriculture, a major effort is required to modernize irrigation and drainage systems and to further develop appropriate management strategies compatible with the financial and socio-economic trends, and the environment. This calls for a holistic approach to irrigation and drainage management and monitoring so as to increase food production, conserve water, prevent soil salinization and waterlogging, and to protect the environment. All this requires, among others, enhanced research and a variety of tools such as water control and regulation equipment, remote sensing, geographic information systems, decision support systems and models, as well as field survey and evaluation techniques. To tackle this challenge, we need to focus on the following issues: affordability with respect to the application of new technologies; procedures for integrated planning and management of irrigation and drainage systems; analysis to identify causes and effects constraining irrigation and drainage system performance; evapotranspiration and related calculation methods; estimation of crop water requirements; technologies for the design, construction and modernization of irrigation and drainage systems; strategies to improve irrigation and drainage system efficiency; environmental impacts of irrigation and drainage and measures for creating and maintaining sustainability; institutional strengthening, proper financial assessment, capacity building, training and education. Copyright © 2002 John Wiley & Sons, Ltd. Résumé Aujourd'hui le problème critique pour l'humanité est comment manier la compétition intensifiante pour de l'eau entre les centres urbains en expansion, pour des activités traditionnellement agricoles et pour l'usage de l'eau fluviale prescrit par des conditions écologistes. Dans le secteur agricole les perspectives d'agrandir les champs cultivés bruts sont limitées par le nombre diminuant des terrains économiquement attractifs pour des projets d'irrigation et du drainage de grande envergure. Par conséquent l'augmentation nécessaire de la production agricole comptera surtout sur une évaluation plus précise du besoin des plantes d'un côté, et de l'autre sur de grandes améliorations dans la construction, dans l'opération, dans le management et dans la performance des systèmes d'irrigation et du drainage. On peut attribuer les défauts des systèmes actuels et l'incompétence d'exploiter durablement les ressources hydriques de surface et souterraines au planification, au système de la gestion de l'eau et au système du développement. Cela est partiellement dû à l'incapacité des ingénieurs, des planificateurs et des gérants, de quantifier adéquatement les effets des projets d'irrigation et de drainage sur les ressources hydriques et d'utiliser ces résultats pour améliorer la technologie, la planification et la gestion de l'eau. Pour profiter le mieux possible des investissements dans l'agriculture, on exige un effort considérable pour moderniser les systèmes d'irrigation et de drainage et pour développer des stratégies de gestion de l'eau qui doivent être appropriées et compatibles avec les tendances financières et socio-économiques et avec l'environnement. Ceci a besoin d'une procédure holistique pour la gestion et le monitorage de l'eau, pour augmenter la production d'aliments, pour conserver l'eau, pour prévenir la salination du sol et pour protéger l'environnement. Tout cela demande, entre autres choses, une recherche d'avant-garde et une variété d'instruments comme les contrôles du régime hydrique et les appareils de régulation, la télédétection, les systèmes de l'information géographique, les systèmes et les modèles de support de décision et de même les levés sur le terrain et les techniques d'évaluation. Pour entreprendre ce défi nous devons nous concentrer sur les questions suivantes: capacité de mettre enoeuvre des technologies nouvelles; le développement des procédures pour intégrer la planification et la gestion des systèmes d'irrigation et de drainage; l'analyse pour identifier les causes et les effets de forcer à la performance des systèmes d'irrigation et de drainage; l'évapotranspiration et les méthodes de calcul en question; l'évaluation des exigences hydriques des cultures; les technologies pour le dessein, la construction et la modernisation des projets d'irrigation et de drainage; les stratégies pour améliorer l'efficacité des systèmes d'irrigation et de drainage; les impacts des projets d'irrigation et de drainage et des mesures appropriées pour créer et entretenir la durabilité; l'amélioration du contexte institutionnel, l'évaluation financière, la formation et l'amélioration des compétences techniques. Copyright © 2002 John Wiley & Sons, Ltd. [source] Economic Liberalization and Smallholder Productivity in Tanzania.JOURNAL OF AGRARIAN CHANGE, Issue 3 2005From Promised Success to Real Failure In the mid-1980s, Tanzania adopted a programme for economic liberalization of the entire economy, including agriculture. After pressure from the IMF and the World Bank in particular, but also from most of the bilateral donors, agricultural producer and input prices were decontrolled, panterritorial prices were abolished, subsidies were removed and trade in agricultural products and inputs was to a large extent taken over by private traders. The international donor community promised that economic liberalization would provide a strong stimulus to Tanzanian agriculture, resulting in increasing yields, increased labour productivity, rising agricultural production and higher incomes. However, available data show that, as far as food crop production is concerned, this promise has not been fulfilled. Even compared to the ,crisis years' 1979,1984, labour productivity, yields and production per capita of food grains stagnated or declined up to the end of the 1990s. Some causes of this failure are discussed. [source] Comments on the Brenner,Wood Exchange on the Low CountriesJOURNAL OF AGRARIAN CHANGE, Issue 1 2002Charles Post The exchange between Brenner and Wood on the Low Countries in the early modern period raises a number of theoretical and historical issues relating to the conditions for the emergence of capitalist social-property relations and their unique historical laws of motion. This contribution focuses on three issues raised in the Brenner-Wood exchange: the conditions under which rural house-hold producers become subject to ,market coercion', the potential for ecological crisis to restructure agricultural production, and the relative role of foreign trade and the transformation of domestic, rural class relations to capitalist industrialization. [source] Impact of Agriculture on Rural Tourism: A Hedonic Pricing ApproachJOURNAL OF AGRICULTURAL ECONOMICS, Issue 1 2005Isabel Vanslembrouck The increased awareness of farmers' role in the maintenance of rural landscapes may contribute to a reassessment of the place of agriculture in society. In this paper, we look at how this role, in relation to landscape, is valued by rural tourists or, in other words, whether it is a response to a societal demand, as is argued by defenders of multifunctional agriculture. The results from a hedonic pricing analysis indicate that landscape features associated with agricultural activities (such as meadows and grazing cattle) positively influence the demand for rural tourism and have a positive impact on the price tourists are willing to pay for rural accommodation. This is also illustrated by the adverse impact of perceived negative externalities from agricultural production (such as intensive maize cultivation) on this price. [source] Agricultural and Economy-Wide Effects of European Enlargement: Modelling the Common Agricultural PolicyJOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2000C. F. Bach The economic impact of extending the Common Agricultural Policy to the Central and Eastern European countries (CEEC) has become a major issue in the European enlargement debate. This paper provides an assessment of the economy-wide effects of European enlargement using a global general equilibrium model where special attention is given to modelling the instruments of the Common Agricultural Policy, the Agenda 2000 proposal and the EU budget. The results indicate a substantial potential for increasing agricultural production in the CEEC. The EU budget will increase significantly and the transfers from EU taxpayers to farmers in the CEEC result in significant welfare gains in the new member countries. In spite of these important transfers the macroeconomic costs for the EU are found to be limited. [source] The Exploitation of Crop Allelopathy in Sustainable Agricultural ProductionJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2005T. D. Khanh Abstract Crop allelopathy may be useful to minimize serious problems in the present agricultural production such as environmental pollution, unsafe products, human health concerns, depletion of crop diversity, soil sickness and reduction of crop productivity. Several crops including alfalfa, buckwheat, maize, rice, rye, sorghum, sunflower, wheat, etc. are affected either by their own toxicity or phytotoxin exudates when their residues decompose in the soil, that show strong suppression on weed emergences. Allelopathic crops when used as cover crop, mulch, smother crops, green manures, or grown in rotational sequences are helpful in reducing noxious weeds and plant pathogen, improve soil quality and crop yield. Those crop plants, particularly the legumes, incorporated at 1,2 tons ha,1 (alfalfa, buckwheat, rice by-products), which can give weed reduction and increase of rice yield by 70 and 20 %, respectively, are suggested for use as natural herbicides. Allelochemicals from allelopathic crops may aid in the development of biological herbicides and pesticides. Cultivating a system with allelopathic crops plays an important role in the establishment of sustainable agriculture. The introduction of allelopathic traits from accessions with strong allelopathic potential to the target crops will enhance the efficacy of crop allelopathy in future agricultural production. [source] Spring Cereals for Forage and Grain Production in a Cool Maritime ClimateJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2003A. G. Todd Abstract Newfoundland's climate is marginal for agricultural production. The availability of locally grown cereal grain and high-quality forage are major limitations to successful animal agriculture in this region. Here, our overall objective was to compare several spring cereal species for both annual forage and grain production in Newfoundland's cool Maritime climate. Several varieties of barley (Hordeum vulgare L.), wheat (Triticum aesitivum L.), oats (Avena sativa L.) and pea (Pisum sativum L.),cereal mixtures for forage yield and quality, as well as grain yield and maturity, were compared in field trials on the east and west coasts in both 1999 and 2000. Barley headed earliest, yielded greatest forage dry matter, had lowest forage protein and acid detergent fibre (ADF) percentages, and had neutral detergent fibre (NDF) mean values greater than those of pea,cereal mixtures, but less than those of oats and wheat. Forage harvested from pea,cereal mixtures was similar to that of barley for yield, ADF and NDF, while P and protein percentage were much greater. Barley matured 10,15 days earlier than both wheat and oats. In general terms, all three spring cereals exhibited similar grain yield potential. Oats tillered less, but compensated by producing more kernels spike,1. Days to maturity for cereal grains in western Newfoundland were roughly similar to those reported for the Maritime provinces of Canada. Yield and maturity results for both forage and grain production suggest that eastern Newfoundland is a unique agro-ecoregion in North America, and agronomic recommendations specific to other regions may not be applicable in this region. [source] Long-term enhancement of agricultural production by restoration of biodiversityJOURNAL OF APPLIED ECOLOGY, Issue 1 2007JAMES M. BULLOCK Summary 1Experimental manipulations have shown positive impacts of increased species richness on ecosystem productivity, but there remain some questions about this relationship. First, most studies last < 4 years, which raises issues about whether diversity,productivity relationships are maintained in mature communities. Secondly, the conservation relevance of many studies is debatable. We addressed both issues using long-term experimental studies of the agriculturally relevant hay yield of recreated species-rich grasslands. 2Grasslands were recreated within replicated experiments in ex-arable fields at two sites in southern England by using either species-poor or species-rich seed mixtures. The species-poor mixture comprised seven grasses as recommended for grassland creation in English agri-environment schemes. The species-rich mixture comprised 11 grasses and 28 forbs and was designed to recreate a typical southern English hay meadow. 3After 8 years the plots sown with species-rich mixtures resembled target diverse community types. The plots sown with species-poor mixtures had been colonized by a number of forbs but had lower numbers of grasses, legumes and other forbs than the species-rich plots. Increased hay yield of the species-rich plots in the first years of the experiments have been described in an earlier paper, and these differences were maintained after 8 years. 4In the eighth year the species-rich plots had an average 43% higher hay yield than the species-poor plots. Regression analysis showed that the variation in hay yield was related to differences in the number of non-leguminous forbs and showed no relation to grass or legume numbers. This suggests increased hay yield is an effect of the greater range of life forms exhibited by forbs rather than a simple fertilizing effect of legumes. 5The nitrogen content and phosphorus content of the hay showed complex treatment effects over time. However, the nutritional value of the hay was above the minimum requirements for livestock. 6Synthesis and applications. The aims of conservationists and farmers can often be in conflict. This study has shown that the recreation of diverse grasslands of conservation value can have a positive impact on hay yield, which benefits the farm business, and this is repeated across differing sites. Because the effect is maintained over time, farm income will be increased in the long term. [source] Meeting the ecological challenges of agricultural change: editors' introductionJOURNAL OF APPLIED ECOLOGY, Issue 6 2003S. J. Ormerod Summary 1The global need for agricultural production has never been greater. Nor has it ever been more complex due to the needs to balance global food security, optimum production, technological innovation, the preservation of environmental functions and the protection of biodiversity. The role of ecologists in finding this balance is pivotal. 2In support of this role, ecologists now have very substantial experience of agricultural systems. We can understand, recognize and sometimes predict, at least qualitatively, the effects of pesticide applications, fertilizer use, drainage, crop choices and habitat modifications on farmland organisms, agro-ecosystems or other ecosystems influenced by agricultural land. 3In instances of greater uncertainty, for example under changing climates, where environmental stresses on ecosystems are interactive, and where ecosystem management or restoration must adapt to new technologies, the investigative skills and experience of ecologists are even more crucial in problem solving. 4There are, nevertheless, contrasting examples of good and bad practice in knowledge-transfer between ecologists and the communities who need our knowledge. The UK farm-scale evaluations of genetically modified crops, for example, involved ecologists at all stages from design and data collection to advocating policy. By contrast, many European agri-environment projects appear to have been developed and evaluated with only modest ecological advice. We advocate fuller involvement of ecologists in the development and evaluation of the European Union Common Agricultural Policy. 5This special profile of seven agriculturally related papers illustrates effectively the array of approaches used by applied ecologists in addressing agricultural questions: modelling, meta-analysis, surveys, transect studies, classical experiments, seedbank assays and process studies based on modern ecological methods. With over 20% of recent papers in the Journal of Applied Ecology reflecting agricultural issues, agro-ecology continues to represent one of the pre-eminent areas of applied ecology that is unlikely to diminish in importance. [source] | ||||||||||||||||||||||||||||||||||||||||