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1.
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   

2.
The relative importance of seven goals were elicited for Louisiana beef and dairy producers using the fuzzy pair‐wise comparison method. Beef producers were more concerned with maintaining and conserving land, while dairy producers were more concerned with financial goals such as maximizing profit and avoiding years of loss or low profit.  相似文献   

3.
ICT and agricultural productivity: evidence from cross-country data   总被引:2,自引:0,他引:2  
This article carries out agricultural production function estimations, based on data for the period 1995–2000 on 81 countries, to present empirical evidence on the relationship between the adoption of information and communication technology (ICT) and agricultural productivity. It is found that new ICT has a significantly positive impact on agricultural productivity. The evidence suggests that the adoption of modern industrial inputs in agricultural production relies on the information and communication infrastructure. However, the empirical evidence from this study also suggests that new ICT could be a factor for the divergence between countries in terms of overall agricultural productivity. Not only do we find that the ICT adoption levels of the richer countries are much higher than those of the poorer countries, but also that returns from ICT in agricultural production of the richer countries are about two times higher than those of the poorer countries. A plausible explanation for the poorer countries' relatively low productivity elasticity of ICT is the lack of important complementary factors, such as a substantial base of human capital.  相似文献   

4.
Agriculture, pesticides and the ecosystem   总被引:1,自引:0,他引:1  
Economists have a good understanding of intra-economic interdependence and a mature methodology of modelling it. Ecologists focus on the complex and sensitive interactions of species in ecosystems. This paper’s objective is to suggest a new micro-foundation of ecosystem analysis based on economic methodology, to integrate the analyses of the ecosystem and the economy and focus on the interface of ecosystem-economy relations. Agriculture forms a major part of this interface. The basic assumption is that in the short run the individual organisms of all species behave as if they optimise their costly offensive and defensive activities given other organisms’ activities (Nash-behaviour).We consider an ecosystem with three species in a unidirectional food chain: buzzards feed on mice, mice feed on grain, and grain feeds on solar energy. A fourth species, humans, also feeds on grain. Humans intervene in the ecosystem in various ways. They can grow grain by using seed, farm labour, pesticides and possibly nature conservation measures to maintain buzzard habitat. Short-run ecosystem equilibrium is characterised, and it is shown, in particular, how this equilibrium depends on farming activities. We then link this ecosystem model to a simple model of an agricultural economy. Both systems are solved for equilibrium simultaneously. From an economic perspective the ecosystem induces positive and negative externalities in agricultural production and in consumer ‘green’ preferences.The inefficiencies of the competitive economy are identified and some possibilities to restore efficiency through corrective taxes or subsidies are briefly discussed. We also outline how short-run equilibria are connected through ecosystem stock-flow relationships. Due to the complexity of the inter-temporal analysis, the resulting ecosystem dynamics cannot be characterised in general analytical terms. It is a topic for future research to study the dynamics in numerical analysis to understand under which conditions the joint ecological and economic system is driven toward a (sustainable) steady state.  相似文献   

5.
This study applies a production function approach to value the groundwater recharge function of the Hadejia‐Nguru wetlands in northern Nigeria. The groundwater recharge function supports dry season agricultural production which is dependent on groundwater abstraction for irrigation. Using survey data this paper first carries out an economic valuation of agricultural production, per hectare of irrigated land. We then value the recharge function as an environmental input into the dry season agricultural production and derive appropriate welfare change measures. Welfare change is calculated using the estimated production functions and hypothetical changes in groundwater recharge and hence, groundwater levels. By focusing on agricultural production dependent solely on groundwater resources from the shallow aquifer, this study establishes that the groundwater recharge function of the wetlands is of significant importance for the floodplain.  相似文献   

6.
In earlier debates on economic development, the agricultural sector's role was somewhat controversial. While dualistic models highlighted the importance of agriculture, the mainstream literature placed a greater emphasis on the creation of a modern industrial sector. Soon agriculture disappeared from the mainstream development literature to re‐emerge recently with a variety of multiple‐sector growth models emphasizing the key role of agriculture and specifically technology in agriculture. This article is an empirical cross‐country analysis of agricultural technology's role in economic development. Specifically, the hypothesis being tested is whether improvements in agricultural technology have a significant impact on long‐run economic growth. The results indicate that agricultural modernization has a positive effect on both measures of economic growth and human development.  相似文献   

7.
Understanding the relationship between soil fertility dynamics and crop response is conceptually appealing. Even more appealing is comprehension of the spatial and temporal heterogeneity of these connections over a production surface and across seasons. But gaining knowledge about these interactions is difficult because nutrient carryover dynamics and crop response to inputs are determined simultaneously on the one hand, and sequentially on the other. A second problem enters when crops are rotated, for example, the corn [Zea mays (L.) Merr.]–soybean [Glycine max (L.) Merr.] system commonly practiced in the U.S. Corn Belt. This article examines nutrient carryover–crop response dynamics using data from a corn‐soybean, variable rate nitrogen (N), and phosphorous (P) experiment conducted over five years in Minnesota, USA. Site‐specific corn response to N and P and soybean response to P is estimated with a P carryover equation. Estimates are used in a dynamic programming model to determine site‐specific optimal N and P fertilizer policies, soil P evolution, and profitability. The net present value of managing N and P site‐specifically is compared to a strategy in which these inputs are managed uniformly following Extension guidelines. The results suggest that when P carryover is accounted for in determining optimal P fertilizer rates, returns to the variable rate strategies are higher than returns to a uniform or whole‐field management strategy.  相似文献   

8.
In this paper, we develop an empirical model to decompose the evolution of the agricultural share of GDP into three components: price changes, factor endowment changes and technological change. Our results suggest that relative prices have a positive but small influence on the share of agriculture in GDP in both the long‐run and the short‐run. An increase in capital per unit of labor, on the other hand, is associated with a smaller agricultural share. Technical change has been biased in favor of the agricultural sector but this effect has been swamped by the magnitude of the input effects, in particular, the changes in the capital‐labor ratio.  相似文献   

9.
There is growing interest in Nova Scotia's Environmental Farm Plan (NS EFP) program among farmers and policy makers because of several reasons. First, effectiveness of standardized or uniform beneficial management practices in mitigating the negative environmental impacts from agriculture is limited by inherent heterogeneities in agricultural production systems. In addition, there is heightened interest in farmers generating ecological goods and services to society. This study investigates the determinants of participation in the NS EFP program. A discrete choice model of NS EFP participation was applied to a sample of 83 farmers (representing a 31% response rate). To increase relevance of the study to program administrators, the study also examined farmers’ use of various channels and sources of information on farm conservation practices. The most used sources of information on farm conservation practices include a mix of interpersonal sources and government agencies. Although online information (especially those available for free) appears to be gaining popularity in usage, overall, electronic and computer channels of information (especially radio and television) were used less compared with traditional channels of communicating farm conservation information (such as newsletters and agricultural magazines). Regression analysis suggests that farm characteristics (i.e., farm type, farm size, farm income) and farmer capacity variables (i.e., specialized training and knowledge from EFP program information sessions and workshops, and on-farm stewardship demonstrations) were significant determinants of environmental farm planning.  相似文献   

10.
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   

11.
This paper analyzes the impact of peer choices on the decision to adapt to climate change in rural Ethiopia. Two IVs are employed (peer-of-peer choices and peer-of-peer information sources) in order to tackle the issue of endogeneity. Through the use of a 3-year panel of farmers in the Nile Basin region, we find that peer choices positively affect the uptake of different adaptation strategies. A 10 percentage point increase in the share of peers using a specific strategy translates to an increase in the likelihood of adaptation between approximately 7% and 14%. This emphasizes the importance of social networks to achieve adaptation to climate change in sub-Saharan Africa.  相似文献   

12.
We summarize recent statistical analyses that link agricultural yields to weather fluctuations. Similar to other sectors, high temperatures play a crucial role in predicting outcomes. Climate change is predicted to significantly increase high temperatures and thereby reduce yields. How good are such models at predicting future outcomes? We show that a statistical model estimated using historic US data on corn and soybean yields from 1950 to 2011 is very capable of predicting aggregate US yields for the years 2012–2015, where 2012 was much hotter than normal and is expected to become the new normal under climate change. We conclude by discussing recent studies on the implication of predicted yield declines with a special focus on adaptation and commodity prices.  相似文献   

13.
The Lore Lindu region in Indonesia—as in many forest frontier areas in Southeast Asia—has experienced rapid deforestation due to agricultural expansion in the uplands, at the forest margins. This has resulted in aggravated problems of erosion and water availability, threatening agricultural productivity growth. At the same time, technical progress is promoting agricultural intensification in the lowlands. In this article, we examine how improved technologies for paddy rice cultivation in the lowlands have affected agricultural expansion and deforestation in the uplands. The question of a “forest‐saving” or “forest‐clearing” effect related to technical innovation is important from a sustainable development perspective and remains a controversial issue in the literature. We address this question for the Lore Lindu region with an empirical model in which expansion in the lowlands and the uplands is estimated simultaneously. We use data from an extensive village survey conducted in the region, combined with GIS data. To guide the empirical analysis, we develop a theoretical framework based on a Chayanov‐type agricultural household model. The model analyzes farmers' land allocation decisions, taking into account the lowland–upland dichotomy in the agricultural sector. The empirical findings, corroborated by the analytically derived results, show how technical progress for lowland production affects land use at the forest margins and how these effects depend on the factor‐intensity of the technology. The findings imply specific rural development policies for sustainable agricultural intensification in forest frontier areas.  相似文献   

14.
Agriculture is unique among economic sectors in the nature of impacts from climate change. The production activity that transforms inputs into agricultural outputs involves direct use of weather inputs (temperature, solar radiation available to the plant, and precipitation). Previous studies of the impacts of climate change on agriculture have reported substantial differences in outcomes such as prices, production, and trade arising from differences in model inputs and model specification. This article presents climate change results and underlying determinants from a model comparison exercise with 10 of the leading global economic models that include significant representation of agriculture. By harmonizing key drivers that include climate change effects, differences in model outcomes were reduced. The particular choice of climate change drivers for this comparison activity results in large and negative productivity effects. All models respond with higher prices. Producer behavior differs by model with some emphasizing area response and others yield response. Demand response is least important. The differences reflect both differences in model specification and perspectives on the future. The results from this study highlight the need to more fully compare the deep model parameters, to generate a call for a combination of econometric and validation studies to narrow the degree of uncertainty and variability in these parameters and to move to Monte Carlo type simulations to better map the contours of economic uncertainty.  相似文献   

15.
This article highlights the main changes observed in Brazilian agriculture and analyzes the connections of the observed changes in global agriculture. My approach to the analysis focuses the main drivers of changes, where institutions play a central role. Three driving forces are are considered: first, the effects of global demand for food, fiber, and energy; second, the sustainability debate; and third, the bio‐energy paradigm. Each driver presents both local as well as global effects. The article does not emphasize the impact changes in Brazil had on the global agricultural landscape but argues that the impacts run from local and global changes, which cannot be discussed separately.  相似文献   

16.
Consumption has been recognized as a more reliable indicator of household well‐being than income. Although a considerable body of literature has examined income inequality between farm and nonfarm households, little is known about inequality in consumption. This research aims to fill this knowledge gap by investigating consumption disparity between farm and nonfarm households. Using a nationally representative household survey from Taiwan, we apply an unconditional quantile regression‐based decomposition method to decompose the differences in the distribution of household expenditure between these farm and nonfarm households. The results indicate that differences in the observed characteristics between these two types of households explain most of the consumption inequality. Moreover, the difference in the education level of the farm operator, household income, and the degree of urbanization are particularly important.  相似文献   

17.
The proportion of agricultural production that is being transformed into biofuels has been growing worldwide over the last decade. This has spurred the food versus fuel debate. This article aims at shedding light on this issue by studying price volatility relationships between food and biofuel prices in Spain. We use an asymmetric MGARCH model to evaluate volatility spillovers between the Spanish biodiesel blend and refined sunflower oil prices. Empirical results confirm that there are bidirectional and asymmetric volatility spillovers between these two prices.  相似文献   

18.
Today, the international community faces two major development challenges: how to ignite growth and how to establish democracy. Economic research has identified two plausible hypotheses regarding this association. The first hypothesis emphasizes the need to start with democracy and institutions that secure property rights. The second hypothesis emphasizes the need to start with physical and human capital accumulation. In this article, we discuss some of the econometric evidence on the relationship between institutions, human capital, and agricultural productivity growth across developed and developing countries with the objective of finding support for one or the other hypothesis. We find that most variables used in the literature to capture the effect of institutions are not independent of the process of growth. While no evidence of causation from political institutions to agricultural productivity growth is found, human capital accumulation emerges as an important source of growth.  相似文献   

19.
Projections of future productivity growth rates in agriculture are an essential input for a great variety of tasks, ranging from development of an outlook for global commodity markets to the analysis of interactions between land use, deforestation, and ecological diversity. Yet solid projections for these variables have proven elusive—particularly on a global basis. This is due, in no small part, to the difficulty of measuring historical total factor productivity growth. Consequently, most productivity projections are based on partial factor productivity measures that can be quite misleading. The purpose of this work is to provide worldwide forecasts of agricultural productivity growth till the year 2040 based on the latest time series evidence on total factor productivity growth for crops, ruminants, and nonruminant livestock. The results suggest that most regions in the sample are likely to experience larger productivity gains in livestock than in crops. Within livestock, the nonruminant sector is expected to continue to be more dynamic than the ruminant sector. Given the rapid rates of productivity growth observed recently, nonruminant and crop productivity in developing countries may be converging to the productivity levels of developed countries. For ruminants, the results show that productivity levels in developing countries are likely to be diverging from those in developed countries.  相似文献   

20.
This article explores how data envelopment analysis (DEA), along with a smoothed bootstrap method, can be used in applied analysis to obtain more reliable efficiency rankings for farms. The main focus is the smoothed homogeneous bootstrap procedure introduced by Simar and Wilson (1998) to implement statistical inference for the original efficiency point estimates. Two main model specifications, constant and variable returns to scale, are investigated along with various choices regarding data aggregation. The coefficient of separation (CoS), a statistic that indicates the degree of statistical differentiation within the sample, is used to demonstrate the findings. The CoS suggests a substantive dependency of the results on the methodology and assumptions employed. Accordingly, some observations are made on how to conduct DEA in order to get more reliable efficiency rankings, depending on the purpose for which they are to be used. In addition, attention is drawn to the ability of the SLICE MODEL, implemented in GAMS, to enable researchers to overcome the computational burdens of conducting DEA (with bootstrapping).  相似文献   

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