Bio-economic evaluation of farmers’ perceptions of viable farms in western Kenya

Arable land in western Kenya is under considerable pressure from increasing human population. Rural households depend on farming for at least part of their livelihood, and poverty rates are among the highest in Kenya. Land is often depleted of nutrients, and for most farmers, access to inputs and markets is poor. There is a need to identify options that are manageable within the context of the farmer’s resource base and the household’s objectives that could improve farm household well-being. In this study we integrated qualitative informal participatory approaches with quantitative mathematical programming and biophysical simulation modelling. Households in four sub-locations in Vihiga District were clustered and pilot cases identified. Meetings were held with farmers to elicit their perceptions of what their ideal farm would look like, and how its performance might compare with their own farm’s performance. With farmers’ help, a range of scenarios was analysed, relating to changes in current enterprise mixes, changes in current farm sizes, and changes in prices of staples foods and cash crops. A considerable mismatch was found between farmers’ estimates of their own farm’s performance, and what was actually produced. There seems to be a threshold in farm size of 0.4 ha, below which it is very difficult for households to satisfy their income and food security objectives. Even for larger farms whose households are largely dependent on agriculture, the importance of a cash crop in the system is critical. There is a crucial role for extension services in making farmers aware of the potential impacts on farm revenue of modest changes in their farm management systems. We are monitoring nine households in the district, whose farmers have made some changes to their system in an attempt to increase household income and enhance food security.     

Exploring the link between farmers' objectives and the phenomenon of pasture degradation in the beef production systems of Central Brazil

In Central Brazil, half the area under sown pasture suffers from the phenomenon of pasture degradation; overgrazing is believed to be the main cause. Farmers' objectives and their links to the practice of overgrazing have been explored to obtain a better understanding of the decisions related to the setting of the stocking rate. A survey of beef cattle farmers was carried out, preceded by an exploratory poll of experts on such production systems. The method of paired comparisons was used for eliciting and analysing farmers' objectives. ‘Intergenerational transfer’ and ‘cattle ownership’ are the most dominant objectives. Because cattle ownership is implicitly included in the assets involved in intergenerational transfer, possessing cattle assumes an outstanding importance in the hierarchy of farmers' objectives. These findings elucidate the paradox of overgrazing and provide a basis for treating the perception on the influence of objectives on the degradation phenomenon from being a conjecture to that of an empirically valid hypothesis. They also suggest the need for incorporating the objective ‘maximise the number of cattle owned’ in the analysis and modelling of stocking rate decisions.     

Corn yield functions of irrigation and nitrogen in Central America

Summary This paper reports the results of a three-year field study conducted in El Salvador, Central America to develop yield response functions for corn to irrigation levels and nitrogen fertilizer. Four levels of irrigation were imposed using two application methods, furrow and trickle, in combination with four nitrogen fertilizer rates. Yields generally increased with higher levels of applied water and with higher nitrogen rates up to 200 kg N/ha, with a strong interaction between these two variables. Yield was independent of irrigation method although less water was applied with the trickle system.In cooperation with the El Salvador Ministry of Agriculture and Livestock and the United States Agency for International DevelopmentPartial support was provided under Contract AID/ta-c-1103Research Engineer, Professor of Soils, Research Agronomist, Research Assistant, Utah State University; and Agronomist, Peace Corps, respectively     

Technological change in agriculture—The systems movement and power

In agriculture the systems approach has almost become orthodoxy. It is widely accepted as an intellectual framework for implementing change. This paper argues that current systems thinking, in seeking to define the sociological underpinnings of the systems movement, fails to address adequately unequal power in human organizations.This paper is concerned with power. It begins by emphasizing the multiplier effect of technology in bringing about change. It then argues that technology is not neutral since changes in practices brought by technological innovations also result in social changes. The theme is developed that the direction and implementation of technological change must confront the politics of power.A perspective for action in the social world is proposed based on an analysis of power in organizations in terms of authority and influence and on the resolution of conflict between interest groups and coalitions by negotiation, using the power-dependence theory. This leads to a framework for implementing change which employs the systems approach in the analysis of natural world systems and a power perspective for action in the social world.     

Unravelling the rationale of `overgrazing' and stocking rates in the beef production systems of Central Brazil using a bi-criteria compromise programming model

In Central Brazil, the long-term sustainability of beef cattle systems is under threat over vast tracts of farming areas, as more than half of the 50 million hectares of sown pastures are suffering from degradation. Overgrazing practised to maintain high stocking rates is regarded as one of the main causes. High stocking rates are deliberate and crucial decisions taken by the farmers, which appear paradoxical, even irrational given the state of knowledge regarding the consequences of overgrazing. The phenomenon however appears inextricably linked with the objectives that farmers hold. In this research those objectives were elicited first and from their ranking two, `asset value of cattle (representing cattle ownership)' and `present value of economic returns', were chosen to develop an original bi-criteria Compromise Programming model to test various hypotheses postulated to explain the overgrazing behaviour. As part of the model a pasture productivity index is derived to estimate the pasture recovery cost. Different scenarios based on farmers' attitudes towards overgrazing, pasture costs and capital availability were analysed. The results of the model runs show that benefits from holding more cattle can outweigh the increased pasture recovery and maintenance costs. This result undermines the hypothesis that farmers practise overgrazing because they are unaware or uncaring about overgrazing costs. An appropriate approach to the problem of pasture degradation requires information on the economics, and its interplay with farmers' objectives, for a wide range of pasture recovery and maintenance methods. Seen within the context of farmers' objectives, some level of overgrazing appears rational. Advocacy of the simple `no overgrazing' rule is an insufficient strategy to maintain the long-term sustainability of the beef production systems in Central Brazil.     

Managing water in agriculture for food production and other ecosystem services

Agricultural systems as well as other ecosystems generate ecosystem services, i.e., societal benefits from ecological processes. These services include, for example, nutrient reduction that leads to water quality improvements in some wetlands and climatic regulation through recycling of precipitation in rain forests. While agriculture has increased ‘provisioning’ ecosystem services, such as food, fiber and timber production, it has, through time, substantially impacted other ecosystem services. Here we review the trade-offs among ecosystem services that have been generated by agriculture-induced changes to water quality and quantity in downstream aquatic systems, wetlands and terrestrial systems. We highlight emerging issues that need urgent attention in research and policy making. We identify three main strategies by which agricultural water management can deal with these large trade-offs: (a) improving water management practices on agricultural lands, (b) better linkage with management of downstream aquatic ecosystems, and (c) paying more attention to how water can be managed to create multifunctional agro-ecosystems. This can only be done if ecological landscape processes are better understood, and the values of ecosystem services other than food production are also recognized.     

龙头企业在小农户滴灌模式推广中的作用

龙头企业不是普通的农产品购销企业,也不是普通的农产品加工企业,它最大的特点就是为农民提供全方位的服务。显然,类似于引进技术、拓展市场这样的工作,分散的农户做不了,乡村集体做不了,在职能没有转变的情况下,政府的农技部门也做不了,必须由一个有实力的企业去做。企业要追求利益的最大化,如果他们的利益与农民的利益相一致,就会产生为农民提供服务的内在动力。     

Role of root and tuber crops in food production strategy for semi-subsistence agriculture

Persistent population pressure on agricultural land in the tropics has led to the evolution of food production strategies heavily weighted towards increasing productivity per unit of land. In many of these same areas, tropical root crops represent a major item in the national food economies. Given this scenario, this paper examines the potential role of tropical root crops in meeting domestic food needs. First, the present contribution of root crops to food production is briefly summarised and used to provide simple guidelines for allocating research resources. These guidelines are somewhat deficient in that they overlook a number of energetic considerations of importance at both the individual producer and national level. To illustrate, a two-goods model of a semi-subsistence agricultural production unit is constructed and some conclusions drawn which lend weight to the opinion that tropical root crop research should receive high priority.     

农村小集中和分散供水的水处理技术与设备

不同于大型集中供水，农村小集中和分散（户）供水有其特殊性和复杂性。正因为其特殊性和复杂性，以及农村饮水安全的投资按人均控制的特点，使得小集中和分散供水的净化和杀菌设备比大型集中供水设备更富有挑战性，需要采用新的结构技术和控制技术。分析了市场现有的几种适合农村小集中和分散供水的净化和杀菌设备，对几种特殊的情况作了一些针对性分析和建议。     

浅析农机化技术与农艺在水稻生产中的增效途径

东港市有5·33万hm2的稻田资源,在农业生产中占有举足轻重的地位。然而,随着水稻种植年限的增加,土壤中有效养分逐年下降,限制了水稻产量的进一步提高。市政府提出要用6年时间,即2010年前将全市水稻单产由目前的451kg提高到600kg。要实现这一目标,广泛采用农机化技术与农艺技术     

Towards sustainable farming systems: Effectiveness and deficiency of the French procedure of sustainable agriculture

There is a widespread consensus about the importance of sustainable agriculture. In France, the Farming Orientation Law of July 1999 has set down a precise procedure for the implementation of sustainable agriculture: the contrat territorial d’exploitation – or territorial farm contract (TFC). This paper aims to analyse the TFC effectiveness. An analysis has been made of the TFCs signed in the Midi-Pyrenees Region in south-western France, using statistical analysis and qualitative surveys of a sample of farms. The results show that the most valuable effects have been mainly economic. Effects regarding social and environmental aspects were very limited. But from the point of view of an integrated approach, indirect effects of TFCs can be observed on social and environmental aspects. These results are explained, on the one hand, by farmers’ motivations guided by economic objectives, and on the other hand, by the dominance of professional farming organisations in the implementation of TFC’s procedure. Given these results, two ways of improving the elaboration procedure for TFCs are proposed. Firstly, technical improvements can be made to the diagnostic assessment of farms, and to the choice of actions addressed by the contract. Secondly, organisational improvements can be applied to TFCs elaboration and implementation process, in order to adopt a participatory approach which would involve all rural stakeholders.     

约翰迪尔338方捆机服务青海

9月15日,约翰迪尔公司技术人员同经销商青海恒信农牧机械有限公司服务人员来到青海省贵南县过马营镇,     

河津市小杂粮生产现状及发展措施

随着人民生活水平的提高,人们越来越需要营养型、保健型、药用型绿色食品.而小杂粮与大宗粮食作物相比,富含各种营养成分,同时具有保健功效,是绿色有机食品的重要原料.通过分析河津市小杂粮产业发展现状及存在的问题,提出发展小杂粮产业的6项措施.     

提高数控铣床生产效率的方法

影响数控铣床加工效率的因素很多,也很复杂。在数控的教学实践和对企业的调查中发现:可以从加工路线、刀具、安装夹紧、切削用量、刀具预调或自动测量、正确的维护保养、加强培训等几个方面着手,缩短换刀时间,实现快速加工,从而达到提高数控铣床加工效率的目的。     

Analysis, assessment, and improvement of fertilizer distribution in pressure irrigation systems

The transformation of traditional irrigation systems into pressure irrigation networks allows water users associations to use central fertigation systems. For efficient fertigation management, however, it is essential to obtain uniform distribution of the injected fertilizer through the system and to understand the hydraulic processes that take place in the central fertigation system. This will allow users to implement strategies that improve fertilizer distribution. In this work we develop a new methodology to improve fertilizer distribution uniformity and apply it to a case study. The results show how fertilizer distribution can be improved by means of proper scheduling of irrigation deliveries. The best results are obtained when fertigating sectors operate without non-fertigating sectors and there are not intermediate irrigations without fertilizer, achieving an improvement of the fertilizer distribution of 10.5%. In addition, this work highlights the difficulties of obtaining uniform distribution of fertilizer in a centralized irrigation system when there are users that do not want to make use of it.     

Livestock water productivity in mixed crop–livestock farming systems of the Blue Nile basin: Assessing variability and prospects for improvement

Water scarcity is a major factor limiting food production. Improving Livestock Water Productivity (LWP) is one of the approaches to address those problems. LWP is defined as the ratio of livestock’s beneficial outputs and services to water depleted in their production. Increasing LWP can help achieve more production per unit of water depleted. In this study we assess the spatial variability of LWP in three farming systems (rice-based, millet-based and barley-based) of the Gumera watershed in the highlands of the Blue Nile basin, Ethiopia. We collected data on land use, livestock management and climatic variables using focused group discussions, field observation and secondary data. We estimated the water depleted by evapotranspiration (ET) and beneficial animal products and services and then calculated LWP. Our results suggest that LWP is comparable with crop water productivity at watershed scales. Variability of LWP across farming systems of the Gumera watershed was apparent and this can be explained by farmers’ livelihood strategies and prevailing biophysical conditions. In view of the results there are opportunities to improve LWP: improved feed sourcing, enhancing livestock productivity and multiple livestock use strategies can help make animal production more water productive. Attempts to improve agricultural water productivity, at system scale, must recognize differences among systems and optimize resources use by system components.     

Economic significance of wool in meat production systems

The contribution of wool to ewe output declines in relative terms as the number and value of lambs reared per ewe increases. This is illustrated by the spectrum of sheep production systems in Great Britain, from extensive hill production where wool accounts for 18% of ewe output, to intensive production out of the main lambing season, where wool only accounts for 6% of ewe output. The ratio of wool production to sheep meat production and their respective prices vary greatly between countries.In Great Britain, as technical efficiency increases, the relative, but not necessarily the absolute, contribution of wool to output declines. Changes in production systems and management, aimed at improving slaughter lamb output per hectare, will also bring about a consequential increase in wool production per hectare.Because wool represents an appreciably lower part of the output in meat producing systems than lamb sales, increases in wool prices have a relatively small effect on gross margins. In lowland flocks a 20% increase in wool prices only increases the gross margin per ewe by 3·1%.Although wool output is considerably less important than lamb sales in Britain it is, nevertheless, worthwhile for the producer to pay close attention to the fleeces produced in order to ensure that he receives the highest returns possible. This is illustrated by reference to the variation in wool returns per ewe between flocks.Fleece weights and quality have a high heritability and are rapidly improved by selection. However, the relative economic value of the annual genetic improvement in increasing the number of lambs reared per ewe is worth five times as much as the annual genetic improvement in fleece weight in lowland flocks; in hill flocks this falls to only twice the value.     

Towards the determination of optimal systems of broiler production

A model for the determination of an optimal system of broiler production subject to the constraints of commercial practice is outlined. The model can accommodate changes in feed prices, dietary composition and strain of bird in addition to permitting investigation of such management factors as length of feeding period and the desirability of segregating the birds according to sex. In this study the model is applied specifically to the choice of an optimal dietary nutrient density. Relevant production relationships have been established from three specially-conducted broiler trials. It is found that, under the conditions assumed, profits are maximised at energy densities in the range 12·1 to 13·2 MJ/kg (with other nutrients in proportion). However, the main emphasis of the paper is on the analytical procedures evolved, rather than on the specific results obtained. It is suggested that such procedures could be used routinely in the broiler industry.     

Simulation of production alternatives in ranching systems in Togo

A simulation model developed by CIAT, Columbia, was used to analyse the economics of large-scale beef production alternatives, comprising different breeds, types of pasture and levels of technical efficiency, for the West African savanna belt based on price-cost relationships in Togo, 1976. With intensive ranching systems an acceptable financial return is only achieved when high productivity levels of the herds are obtained while using low-cost production techniques. These systems have large finance requirements and, thus, involve a high managerial risk. Extensive systems (similar to nomadic systems) with minimum investments in fencing and artificial pastures, seem to be the most profitable alternatives. Available stock numbers are the most binding constraint for livestock development at a regional level, hindering the full exploitation of the main natural resource. Further analysis should be undertaken to see whether sheep and goats, with their higher rates of reproduction, could not significantly accelerate the utilisation of understocked land resources.