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1.
The substitution of capital goods, including new technology, for land and labour has played an important role and has influenced the structure of Sout African agriculture. Farm labour-related trends in the summer rainfall grain-producing area of South Africa are considered. The amount of labour used, the remuneration of labour, the substitution of capital for labour and productivity trends are analyzed. Growth rates were obtained by fitting exponential functions with time as independent variable. The decline in the number of farm employees per 1000 hectares under cultivation since 1970 probably resulted from mechanization and thus capital-labour substitution in maize production, especially in harvesting. Tax concessions on new capital improvements, the subsidization of agriculture in general and the increasing rate of urbanization contributed to this trend. The scarcity of capital relative to unskilled labour, which has been reinforced by policy measures favouring capital intensity (capital formation has increased by 4.0% per annum between 1950 and 1980, compared with an increase of 0.71% per annum in the number of farm employees in the same period); this implies that corrective policy changes are required to improve the present distorted situation. This will enable the commercial agricultural sector of South Africa to play a more meaningful role in the socio-economic development of the whole subcontinent.  相似文献   

2.
Faidherbia albida is a tree species indigenous to semi-arid regions of Africa that reportedly substantially increases maize (Zea mays) yields in its immediate vicinity. In southern Zambia, F. albida is widely used in indigenous maize farming systems and this has apparently increased over the past two decades. Using a combination of interviews, group meetings, and observations, this study sought to understand why this species seems to have recently been embraced, while other technological innovations apparently have not. We observed a bimodal age distribution of the trees in agricultural fields and posit that the missing cohorts were removed as weeds as a result of evolving notions of what constituted modern farming practices in the emerging maize economy. With subsequent research and social promotion of the beneficial effects of F. albida, farmers now allow the trees to grow in their fields. A holonic analysis points to the important relationship of F. albida to contexts that shaped past and current uses of the tree by farmers on the Tonga Plateau: information, maize, cattle, land tenure, and government policy. Advice promulgated by social promotion activities took root in farmer knowledge contexts because of positive regard for F. albida and timeless injunctions against cutting mature specimens. Furthermore, cultivation of the tree was highly compatible with other important contexts in which farmers operate. However, our research also revealed the potential for adoption of the tree to create new tensions arising from the strong gendering of work and crops in the region.  相似文献   

3.
Why do men and women adopt agricultural technologies at different rates? Evidence from Ghana suggests that gender‐linked differences in the adoption of modern maize varieties and chemical fertilizer result from gender‐linked differences in access to complementary inputs. This finding has important policy implications, because it suggests that ensuring more widespread and equitable adoption of improved technologies may not require changes in the research system, but rather introduction of measures that ensure better access for women to complementary inputs, especially land, labor, and extension services.  相似文献   

4.
This article presents results from a study exploring the reasons for low adoption of legume technologies to improve soil fertility by farmers from a community in central Malawi who took part in participatory trials. This study explores the influence of gender roles in agriculture and land ownership and socio-economic differentiation in the community. Because most women do not own land and are traditionally responsible for legume crops, they have little interest in managing soil fertility for maize crops. Men are not interested in using legumes in maize-cropping systems. Some are too poor: this group needs to complement their subsistence maize production with paid labour on the farms of better-off farmers; restricting the labour availability for their own farming activities. Wealthier farmers have access to, and prefer to use chemical fertilizer and cattle manure. Take-up rates among the middle group of farmers were also low. This study discusses how these (and other) factors influence the (non-)adoption of maize-legume technologies in Malawi and the effectiveness of participatory research. It emphasizes how differentiated farmer-realities affect the uptake of technologies identified as promising in participatory field evaluations.  相似文献   

5.
Nepalese mid-hill farmers have shifted from a subsistence-based farming system to an intensified farming system. This paper attempts to describe the evolution of the process of agricultural intensification in the mid-hill region by examining external drivers, trends in fertilizer use, landholding, cropping patterns, irrigation and labour use in the years 1989, 1999 and 2009. Data were obtained by means of structured interviews, focus group discussions, key informant interviews and field observations. The study revealed that modern technology and the involvement of NGOs have facilitated the agricultural intensification process in three ways: (i) by providing access to technology without any financial cost to the farmer, (ii) by increasing the variety and number of crops and encouraging farmers to discontinue crops that had pest problems and (iii) by maximizing the use of chemical fertilizers to increase production. Results showed a significant increase in the application of urea and diammonium phosphate (DAP) and a decrease in the application of farm yard manure (FYM) and muriate of potash from 1989 to 2009 (p < 0.001). The average landholding of 0.76ha in 1989 was reduced to 0.63ha by 2009. The number of crops (rice, maize or millet) cultivated per year increased to at least three crops with the introduction of potatoes and spring rice; however, some crops such as sugarcane and tobacco were not continued as a result of pest problems. Increased nitrogen input could lead to increased N2O emissions; therefore, a better understanding of nitrogen fertilization and quantification of N2O emissions from intensified agriculture is urgently needed to assess the possible environmental impact of input intensification.  相似文献   

6.
The present study was an ex‐post assessment done to validate past funding on cassava research, based on economic surplus approach. Though cassava was introduced as a food crop in Kerala, India from Brazil, it has changed its status to commercial crop at present in Tamil Nadu and Andhra Pradesh states. This was made possible due to intensive research and development efforts of different R&D organizations. Cassava technologies developed enabled in sustaining the crop in the country with the world’s highest productivity. All the cassava production technologies considered in the study resulted in an economic surplus of Rs.3585.87 million in the target domain covering Kerala, Tamil Nadu and Andhra Pradesh. Consumers and producers benefited to the tune of Rs.2090.64 million and Rs.1495.23 million respectively. Net present value of economic gains was estimated to be Rs.3548.76 million. Present value of research investment on cassava production technologies was Rs.37.11 million resulting in benefit cost ratio of 96.63:1 with a high internal rate of return of 104 per cent. Thus the study indicated that the research investments incurred on cassava production technologies development was highly economical and provided evidence to the policy makers that supporting the research investment on underground, under exploited tropical root crops like cassava is an economically viable proposition.  相似文献   

7.
The major biotic constraints to the production of maize, the major staple food in Western Kenya, are field pests such as Striga and stem borers, and low soil fertility. To counter these constraints, new cropping systems have been developed, including “push‐pull,” rotations with promiscuous soybean varieties and green manure crops, and imidazolinone resistant‐ (IR‐) maize. To analyze the technical and economic performance of these technologies, both with and without fertilizer, on‐farm researcher‐managed long‐term trials were implemented over six seasons in two sites each in Vihiga and Siaya districts of Western Kenya. The economic results, based on marginal analysis using a multioutput, multiperiod model, show that the new cropping systems with fodder intercropping (push‐pull) or soybean rotations were highly profitable. Push‐pull is more profitable but requires a relatively high initial investment cost. Green manure rotation, IR‐maize, and fertilizer all increased yields, but these investments were generally not justified by their increased revenue. We argue that research on rotation and cropping systems to tackle pest and soil fertility problems in Africa deserve more attention. This will require increased collaboration between agronomists and economists to set up long‐term experiments with new cropping systems to develop proper economic models.  相似文献   

8.
This paper applies an integrated methodology which is constituted of the following: (i) the Emergy-Data Envelopment Analysis (EM-DEA), (ii) environmental Cost-Benefit Analysis (CBA), (iii) Value Chain Analysis (VCA), and (iv) Sustainability Balanced Scorecard (SBSC) approaches, -to support multicriteria decision analysis (MCDA) for strategic agricultural land use planning, which could contribute to improve food security in northern Ghana. Five scenarios of land use and resource management practices for maize production were modelled. The business-as-usual scenario was based on primary data, which were collected using semi-structured questionnaires administered to 56 small-scale maize farmers through personal interviews. The dominant land use was characterised by an external input ≤12 kg/ha/yr inorganic fertilizer with/without the addition of manure in rainfed maize systems. The project scenarios were based on APSIM simulations of maize yield response to 0, 20, 50 and 100 kg/ha/yr urea dosages, with/without supplemental irrigation. The scenarios were dubbed as follows: (1) no/low input systems were denoted by Extensive0, Extensive12, and Intercrop20, and (2) moderate/high input systems were denoted by Intensive50, and Intensive100. The EM-DEA approach was used to assess the resource use efficiency (RUE) and sustainability in maize production systems, Ghana. The measured RUE and sustainability were used as a proxy for further analyses by applying the environmental CBA and VCA approaches to calculate: (a) the environmental costs of producing maize, i.e. resource use measured as total emergy (U), and (b) benefits from the yielded maize, i.e. (b i) food provision from grain measured in kcal/yr, and (b ii) potential electricity (bioenergy) which could be generated from residue measured in MWh/yr. The information which was derived from the applications of the EM-DEA, CBA and VCA approaches was aggregated by applying the SBSC approach to do a sustainability appraisal of the scenarios. The results show that, when labour and services are included in the assessment of RUE and sustainability, Intercrop20 and Intensive50 achieved greater marginal yield, better RUE, sustainability and appraisal score. The same scenarios caused lesser impacts in terms of expansion of area cultivated compared to Extensive0 and Extensive12. Meanwhile the impacts of Intercrop20 and Intensive50 in terms of ecotoxicity, emissions, and demand for resources (energy, materials, labour and services) were lesser compared to Intensive100. The implications of the various scenarios are discussed. The environmental performance of the scenarios are compared to maize production systems in other developing regions in order to put this study within a broader context. We conclude that, the EM-DEA approach is useful for assessing RUE and sustainability of agricultural production systems at farm and regional scales, as well as in connecting the management planning level and regional development considerations.  相似文献   

9.
It is widely recognized that an “African green revolution” will require greater use of inorganic fertilizers. Often‐made comparisons note that fertilizer use rates in Africa are just 10–20% of those in Asia, Europe and the Americas. Most attempts to explain relatively low‐adoption of fertilizer assume yield responses to inorganic fertilization warrant higher application rates and hypothesize that observed use rates are limited by market‐based factors. Another explanation may be that application rates are low because African yields are less responsive to inorganic fertilizer than yields in other regions, and less responsive than analysts perceive. Examining the case of Zambia, we evaluate whether yield response to fertilizers could explain adoption and application rates. A model of yield response is constructed and a combination of estimators is employed to mitigate potential biases related to correlation between fertilizer use and unobserved heterogeneity as well as stochastic shocks. Results indicate higher fertilization rates would be marginally profitable or unprofitable in many cases given commercial fertilizer and maize prices. Phosphoric fertilizer is particularly unprofitable on acidic soils, which are common in Zambia and other areas of sub‐Saharan Africa. We propose feasible recommendations for diversifying the current government strategy to enhance crop productivity.  相似文献   

10.
Factors influencing the profitability of fertilizer use on maize in Zambia   总被引:1,自引:0,他引:1  
Fertilizer use remains very low in most of Africa despite widespread agreement that much higher use rates are required for sustained agricultural productivity growth. This study uses longitudinal farm survey data to estimate maize yield response functions in a relatively high-potential zone of Zambia to determine the profitability of fertilizer use under a range of small-farm conditions found within this zone. The theoretical framework used in this study incorporates agronomic principles of the crop growth process. We generalize the asymmetric production models and define a concept of yield scaling factors. The model distinguishes different roles of inputs and non-input factors in crop production. We estimate the effects of conventional production inputs as well as of household characteristics and government programs on maize yield. The results indicate that recommended fertilizer application rates in the two specific years were often unprofitable, given observed price conditions and the yield response to fertilizer. However, there was substantial variability in yield response to fertilizer based upon the rate of application, the timeliness of fertilizer availability, the use of animal draught power during land preparation, and whether the household incurred the death of an adult member in the past three years. These modifying factors, as well as variations in input and output prices due to proximity to roads and markets, substantially affected the profitability of fertilizer use on maize.  相似文献   

11.
This article examines the relationship between maize productivity and plot size in Zambia. It offers a unique empirical approach. First, it focuses on maize, which is the major crop on small and medium size farms in Zambia, but also accounts for the endogenous determination of the size of the plot devoted to maize. Previous studies have used total farm size or harvested area. Second, it corrects for selectivity in maize cultivation. Third, it controls for differences in land quality and weather conditions across districts. Finally, it offers a structural interpretation of the above framework by modeling farm decisions as a sequential, two‐stage process, in which land is first allocated to the different crops based on the information set of the farmers at the time of planting, and the yield is affected by subsequent application of inputs, the quantities of which may depend on additional information that is revealed after planting. We use this recursive structure and the differences in the information sets over time to identify the model. The results show that the endogeneity of plot size is very important in this analysis. When considering plot size as an exogenous explanatory variable, we find a monotonic positive relationship between the yield of maize and plot size, indicating that economies of scale are dominant throughout the plot size distribution. However, when we correct for the endogeneity of plot size, we find that the inverse relationship dominates the economies of scale in all plots up to 3 ha, which constitute 86% of our sample. These results suggest that market imperfections should be targeted by any policy aimed at increasing maize productivity in Zambia.  相似文献   

12.
Increased attention on government pricing policies among African nations leads directly to a need for information about producer responses to price adjustments. This is especially true in the case of Zambian maize production. Maize is the most important crop grown in Zambia. It accounts for more than 80% of the value of marketed food crops, is heavily relied on for subsistence consumption, and is a staple food in the diet of all Zambian citizens. This paper analyzes the aggregate price response of maize supply in Zambia using a dynamic regression analysis. As a result, short, intermediate and long-run multipliers/elasticities are measured which can be used to analyze the effect of future price policy changes. It was found that a second-order rational distributed lag model best fits the available data. Estimates of short-run elasticities of supply for maize and fertilizer prices are 0.54 and –0.48, respectively. The corresponding estimated long-run elasticities are 1.57 and – 1.44.  相似文献   

13.
To demonstrate the development impact of their outputs, agricultural research and development (R&D) organizations used to focus on the efficiency and effectiveness of technologies. In recent years, innovation systems thinking has started to address institutional and organizational barriers to technological change in African agriculture. The main approach used has been the multi-stakeholder innovation platform (IP). This paper analyses the requirements for improving the competence and skills of IPs actors in agricultural value chains, food systems, and natural resource management. As case studies, it uses IPs in the maize and cassava value chains that were initiated in the dissemination of new agricultural technologies in Africa (DONATA), in both West and Central Africa, and made reference to the rice IPs facilitated by AfricaRice. Yields and incomes in maize and cassava IPs significantly increased and inter-actor relationships and behavioural change among the diverse social and economic operators were enhanced. This achievement built on three capacity development interventions: (i) learning workshops that sensitized and informed technocrats and policy-makers and nurtured their involvement and ownership, (ii) competence and skill training of IP facilitators and practitioners, and (iii) coaching and mentoring of these facilitators and practitioners. To better facilitate IPs, facilitators and practitioners need to learn to observe, recreate, test, and perfect the IP process and value chain approach. Practicable tools that can be visualized and put into practice by the IP actors are essential. The DONATA on which the paper is based has been invaluable in terms of experiential learning.  相似文献   

14.
Maize (Zea mays) shortages and maize price instability continue to occur in Mozambique in spite of policy reforms and great capacity for increased production in northern Mozambique. This study measured the efficiency of spatial maize price arbitrage in Mozambique's post‐reform period. Spatial price inefficiency does not seem to explain why food shortages continue to occur in Mozambique, suggesting nonprice market constraints such as poor infrastructure and poor market institutions as more likely explanations. Baulch's spatial efficiency test indicated that it is not profitable to ship maize from northern surplus maize regions to southern Mozambique. Records of interregional maize shipments show that indeed grain is not being shipped from the north to the south. Market liberalization may have improved spatial price efficiency, but high transfer costs still limit trade and potential benefits from freeing markets. Under these circumstances, food shortages and price instability are likely to continue.  相似文献   

15.
Plant-based precision nitrogen fertilizer application technologies have been developed as a way to predict and precisely meet nitrogen needs. Equipment necessary for precision application of nitrogen, based on sensing of growing wheat plants in late winter, is available commercially, but adoption has been slow. This article determines the expected profit from using a plant-sensing system to determine winter wheat nitrogen requirements. We find that plant-sensing systems have the potential to be more profitable than traditional nonprecise systems, but the existing system simulated was roughly breakeven with a traditional system.  相似文献   

16.
Leguminous agroforestry (AF) species have been investigated and promoted in Malawi as a means to improve soil quality and maize (Zea mays) yields. Our objective was to determine whether AF systems' recommendations that solely consider impacts on average maize yields differ from those that include an analysis of production risk, profitability among different wealth groups and socioeconomic vulnerability. Employing participatory quantitative and qualitative on-farm research techniques, we investigated three AF-based maize/legume relay-cropping practices in southern Malawi. The perennial legumes included Sesbania sesban, Tephrosia vogelii and Cajanus cajan (pigeonpea). We found that AF species recommendations did diverge from those based solely on maximizing maize yields when incorporating risk, profitability and socioeconomic vulnerability as additional variables. For instance, the highest yielding system (the S. sesban/maize relay crop) was never recommended for the most vulnerable farmers based on the vulnerability analysis, and the cropping systems were often more profitable for the least vulnerable farmers than they were for the most vulnerable farmers. Cropping system recommendations based solely on obtaining the highest average maize yields would also have generally overlooked the economic and nutritional importance of pigeonpea, and the difficulty for the most vulnerable farmers to profit from fertilizers, potentially placing these farmers at greater risk.  相似文献   

17.
The incidence of diverse forms of surplus – fixed rents, share rents, profits from direct cultivation and labour rents – remains a conundrum in the study of agrarian organization. The article presents a theoretical account of the form of rent when a dominant landowner faces landowning peasants. From a purely economic standpoint, the surplus-maximizing choice among forms is shown to be contingent not only on their incentive and labour-process characteristics but also on land inequality and labour productivity. By incorporating the difficulty of extracting effort from hired labour as a fixed parameter, political and ideological factors are accommodated as independent additional determinants of the form of agrarian organization. When there is also a class of landless labourers, sharecropping or labour-tying may prove superior to wage-leadership as a form of tacit collusion among dominant and subordinate landowners. Some of these forms of rent extraction are also shown to restrict the monopolist's incentive to adopt technical improvements.  相似文献   

18.
[目的]设施蔬菜种植过程中化肥的过量投入和利用效率低下,造成了严重的环境问题。解决这些问题的农业技术在推广应用过程中又存在农户响应度低、可持续性差等问题。为了提高农业技术推广水平,保证设施蔬菜种植的可持续性,构建全面系统的技术评价指标体系,在技术推广应用时进行科学评价是十分必要的。[方法]文章运用文献分析法、专家咨询法、专家约束下的主成分赋权法,进行实证分析。[结果]构建了由准则层、指标层和子指标层3个层次共27个子指标的设施蔬菜化肥减施增效技术评价指标体系;计算得到各项指标权重,最终结合指标数据得到5项技术模式综合得分及排序:模式1北票市越夏番茄化肥减施(0.443 2)模式3辽中区冬春茬番茄化肥减施(0.343 8)模式2灯塔市越冬番茄化肥减施(0.050 4)模式4南票区冬春茬番茄化肥减施(-0.412 5)模式5凌源市越冬长季节黄瓜化肥减施(-0.425 0)。[结论]根据评价得分结果分别围绕5项技术模式的技术、经济、社会和管理方面进行分析讨论,据此提出了技术模式推广优先序;针对各项技术的优势与劣势提出了发展设施蔬菜的政策建议,对各项化肥减施增效技术模式的完善与应用推广有重要意义。  相似文献   

19.
In Malawi, population growth has reduced opportunities for farmers to expand and cultivate new land. The country's primary farming population is comprised of smallholders, many who cultivate monocultures of maize (Zea mays). To reduce negative outcomes from this practice, intercropping maize with legumes has been promoted. The sustainable intensification (SI) practice was once widely used, but has declined in recent decades. Little is known about the determinants of intercropping or its role in agricultural development. The objective of this study was to examine the drivers of intercropping among smallholders. We used multiple logistic regression analysis to estimate the determinants of intercropping based on a survey of 324 households. Smallholders who sold legumes were more likely to intercrop, contrary to literature positing intercropping as a practice primarily intended to enhance food security. In addition, complementary SI practices such as fertilizer, manure and compost application were more likely to have occurred on intercropped fields relative to sole maize fields. Furthermore, smallholder farmers appeared to apply more fertilizer to their intercropped fields relative to their sole maize fields. The study highlights the value of including field-level characteristics and household socioeconomic survey data to understand farming practices as a means to inform agricultural policy.

Abbreviations: SI: sustainable intensification; MLI: maize-legume intercrop; DL: doubled-up legumes  相似文献   


20.
Small Farm Production and the Standardization of Tropical Products   总被引:2,自引:1,他引:1  
This paper explores the historical relations between labour organization and product qualification in the production of tropical agricultural exports. In supplying international markets for tropical products, peasant farming emerged as the norm for labour organization after the First World War, competing with the large plantations and different systems of forced labour. During the same period, national standards became the dominant tool for product qualification of commodities traded on the global agricultural markets. These standards allow the creation of futures markets and the emergence of traders, instead of auction markets and commission merchants: two changes that were the basis of the subsequent international marketing of peasant-produced commodities. The last part of the paper considers the potential consequences of the current erosion of standards for the position of peasants in tropical export crop cultivation.  相似文献   

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