Yield quality and irrigation with saline water under environmental limitations: the case of processing tomatoes in California

Irrigation with saline water has a positive impact on some quality indices of processing tomatoes, but with concomitant reductions in output quantity. This article studies the impact of the trade‐off between these two factors on optimal water management under waterlogging and costly drainage‐disposal conditions. The focus is on the content of total soluble solids as a quality measure affecting prices paid by California processors to tomato growers. A function relating quality to water and salinity applications and a quality hedonic‐price function are estimated and introduced into a static, field‐level mathematical programming model. The model calculates optimal water management under environmental regulations associated with drainage disposal in California. Findings indicate that only when the quality effect is taken into account does blending fresh surface‐water with saline drain‐water become an optimal strategy. Management and policy implications on the regional scale are discussed.     

Tactical responses to seasonal conditions in whole-farm planning in Western Australia

In dryland agricultural systems, efficient farm management requires a degree of flexibility according to variations in climate from year to year. Tactical adjustments to the mix of farm enterprises can capitalize on good growing conditions and minimise losses under poor growing conditions. In this paper, a discrete stochastic programming model of dryland wheat-sheep farms in Western Australia is used to identify optimal tactical adjustments to climate and to calculate the value of these tactical adjustments. The model, MUDAS, includes nine discrete season types with a wide range of options for tactical adjustments in each. In the standard model, optimal tactical responses increase expected net cash surplus by approximately 22% relative to a fixed or inflexible strategy. In most season types, changes to the long term farm strategy are made on less than 10% of the farm area, although in some seasons over 25% of the farm can require adjustments to the enterprise selected. The benefits of flexibility are not evenly distributed across different season types but occur predominantly in the best and worst seasons. The magnitude of benefits is affected differently by different commodity prices. Benefits of flexibility are due to capitalizing on knowledge about the greater volatility of profits from cropping than from livestock production. Deterministic models and even stochastic models which don't include activities for tactical adjustments miss this key feature of the system.     

Quantifying the socio-economic determinants of sustainable crop production: an application to wheat cultivation in the Tarai of Nepal

This study specifies a procedure to quantify the determinants of sustainable crop production, and applies the method to wheat cultivation in the Tarai of Nepal. Three aspects of sustainability were considered. First, the fertility of the land was found to have deteriorated owing to long-term practices incompatible with soil and drainage conditions. Three-quarters of the farmers had reduced land fertility and for one-third of them the wheat yield was at least 20% lower than for farmers who applied farmyard manure to every crop and adopted a rotation consistent with soil and drainage conditions. Secondly, the study found that it was possible to improve resource-use efficiency in wheat production to give 25% higher production at current levels, type, and quality of farm resources. Resource-use efficiency was significantly related to farm management practices such as crop stand, variety, disease, and land preparation quality, and socio-economic factors such as off-farm job opportunities, poor plot accessibility, and migration. Thirdly, the increasing population pressure on land, decreasing livestock number per cropped area, and diminishing fuel wood sources, significantly reduced farm-based nutrient cycling because farmyard manure had to be used for fuel. This had implications for the higher use of the fossil-based inputs in crop production.     

Soil,water and crop management alternatives in rainfed agriculture in the Sahel: an economic analysis

Most agriculture in the Sahel Region is carried out under rainfed conditions where low and uncertain soil moisture levels limit productivity. Improved soil, water and crop management practices are required to reverse the steady decline in per capita food production and sustain output over the long term. Several technological innovations and related farm management practices are evaluated in a case study of a typical farm in Mali. Through use of a soil-water balance model and a whole-farm economic model an optimal mix of these measures is identified. Compared to a base case where no modern inputs are utilized, the combination of animal traction (oxen team), low levels of NPK fertilizer, tied-ridges, traditional long-season food grain crops and early planting was most effective: food grain output was 35% higher than with the traditional base case; soil erosion was reduced by 72%; and even with residual future soil erosion damage capitalized into current income, net farm income was larger by a factor of almost 45.     

OPTIMAL CULLING POLICY FOR BREEDING EWES

This article demonstrates a method to determine the optimal culling, policy for a sheep breeding flock. A model of the flock is constructed and profitability calculated for different age distributions of ewes. The method is illustrated with data obtained from an actual farm by a farm management consultant.     

Drainwater Management for Salinity Mitigation in Irrigated Agriculture

Salinity and drainage management options include source control, reuse, and evaporation ponds. This article identifies efficient strategies to maintain hydrologic balance in closed drainage basins and evaluates their impact on regional agricultural profits. Theoretical analysis suggests that economic efficiency requires acknowledgment of the nonseparability between water use and land value. Empirically, our solution involves a modest amount of source control, a substantial amount of reuse, and the elimination of evaporation ponds often associated with large environmental damages, while maintaining grower income. Various policy instruments and options are introduced and discussed, including a system of drainwater charges, marketable permits, and land retirement.     

AN OPTIMAL MANAGEMENT MODEL FOR INTENSIVE AQUACULTURE — AN APPLICATION IN ATLANTIC SALMON*

In this paper the optimal management strategy for intensive aquaculture is viewed in terms of a combined strategy of releasing the optimal number of recruits and harvesting those recruits at the optimal harvesting time. A model which can be used to determine the optimal management strategy is developed. In the model the optimal harvesting model documented by Bjorndahl (1988, 1990) in which harvesting and feed costs are considered, is extended by including release costs and how they influence the optimal number of recruits. The model forms the basis for an empirical analysis in which the optimal management strategy for a yearclass of Atlantic salmon farmed in Australia during 1989-91 is considered.     

国有林场改革运用TOT模式研究

深化国有林场改革,加快国有林场发展,是我国新时期林业建设的重要内容。但是目前,运营资本不足和运行效率低下是林场面临的两大突出问题,进行经营改革既是林业经营管理体制改革的重要组成部分,也是林场可持续发展的必然要求。笔者将在基础设施等公共领域中流行的一种TOT(Transfer Operate Transfer)项目运作模式运用于国有林场的改革中,以解决以上问题。文章介绍了TOT模式的含义与特点,分析了国有林场改革运用该种方式的可行性,运作过程中可能出现的风险,并提出了相应的解决对策,以提高国有林场经营活力,经济效益和社会效应。     

Why do farmers have so little interest in futures markets?

A farm financial model with leverage and investment in two farm enterprises is specified. The model is extended to incorporate futures hedging and the Separation Theorem is used to show that optimal hedging is zero. The assumption of a risk‐free asset is relaxed and, while this leads to a violation of the Separation Theorem, the result that optimal hedging is zero is maintained providing that futures markets are efficient. It is concluded that if capital markets are efficient then farmers will have little interest in futures markets except to speculate.     

The impact of climate and price risks on agricultural land use and crop management decisions

This article aims to investigate the impacts of climate change and of lower and more volatile crop price levels as currently observed in the European Union (EU) on optimal management decisions, average income and income risks in crop production in Western Switzerland. To this end, a bioeconomic whole-farm model has been developed that non-parametrically combines the crop growth model CropSyst with an economic decision model using a genetic algorithm. The analysis focuses on the farm level, which enables us to integrate a wide set of potential adaptation responses, comprising changes in agricultural land use as well as crop-specific fertilization and irrigation strategies. Furthermore, the farmer's certainty equivalent is employed as objective function, which enables the consideration of not only impacts on average income but also impacts on income variability.The study shows that that the effects of EU crop prices on the optimal management decisions as well as on the farmer's certainty equivalent are much stronger than the effects of climate change. Furthermore, our results indicate that the impacts of income risks on the crop farm's optimal management schemes are of rather low importance. This is due to two major reasons: first, direct payments make up a large percentage of the agricultural income in Switzerland which makes Swiss farmers less vulnerable to market and climate volatility. Second, arable crop farms in Switzerland have by law to cultivate at least four different crops. Due to these diverse cropping systems and high government direct payments risk does neither under climate change, market liberalization nor combinations thereof, play a very decisive role in arable farming in Switzerland.     

Size matters: Optimal management of dynamic systems with varying size

Many natural and economic systems are managed to deliver the highest benefits to society but are subject to regime shifts. We specifically consider the variability of the size of the system itself as a key driver of a regime shift. We address the question of how the optimal management of these systems should vary with its size. Put simply, certain management options might work when the system is of a given size, while others might be preferred when the system has grown or shrunk. In this paper, we develop a model that allows us to analyse the effect of the size of the system on its optimal management. We apply this model to a case of water pollution in a reservoir/lake that varies in size over time: sometimes the lake is deep and sometimes it is shallow. Numerical simulations were conducted to compare optimal management of the reservoir with and without explicitly modelling its size variation. The findings show that the overall social costs of optimally managing pollution are significantly smaller when the variability in size is taken into account. This is due to differences in the timing and magnitude of the optimal control. The key implication is that the variability of the size of a system should be explicitly considered in this type of management problems.     

Plot-level technical efficiency accounting for farm-level effects: Evidence from Chilean wine grape producers

This paper applies alternative panel data models to a cross-sectional dataset that contains observations at the plot level for a sample of wine-grape farms in Central Chile. The input–output data as well as key attributes of the production system are at the plot level, at which individualized management exists. However, plots belonging to a particular farm are also subject to overall centralized (farm-level) management. Thus, this data configuration offers the possibility of analyzing technical efficiency (TE) both across plots and across farms. A Generalized True Random Effects model, which permits the separate identification of farm-level and plot-level inefficiency while controlling for unobserved farm-level heterogeneity, shows that TE varies across farms but not among plots within the same farm. Geographical location also affects grape production and agro-climatic conditions influence production levels, with grape farms located on cooler zones producing significantly less than their counterparts in warmer zones, as expected. The analysis underscores the value of using recent methodologies typically applied to panel data when cross-sectional information is available for individual plots within a farm unit or in similar settings.     

COMPARATIVE ANALYSIS OF FARM ACCOUNTS

With the development of farm management extension services in Australia, a need has arisen for an analytical technique which can be handled by extension officers and readily comprehended by farmers. Inter farm comparison met this need at a similar stage of development in the United States and United Kingdom, and its application to Australian conditions is discussed. Comparative analysis is presented as an integral feature of farm management accounting.     

Impacts of risk aversion on whole-farm management in Syria

This article reports on a study of the impact of risk on farm management practices in northern Syria, focusing particularly on how these are affected by risk aversion and farm size. The study is based on production data from an eight-year field trial and on prices from market surveys. A large linear programming model is built, representing the eight years as observations from a discrete probability distribution. Risk aversion is modelled by inclusion of a utility function with constant relative risk aversion, represented using the DEMP/UEP approach.     

How training and innovation link to farm performance: a structural equation analysis

The complexity of modern farm management places great demands on the skill, knowledge and capability of farm managers and their families. Keeping abreast of emerging technologies and innovations that can affect each key farm enterprise, and knowing how best to marshal the resources required for profitable farm production, are key tasks of farm management. This study draws on a longitudinal data set of 240 broadacre farmers to compare and analyse their farm performance over a decade. Using structural equation modelling, we examine relationships between the farm family's involvement in training, their human capital, their use of various innovations and ultimately the linkages of these factors to farm financial and productivity performance. Several statistically significant inter‐relationships are found, and some factors are shown to have significant positive links to farm performance. We find that training undertaken by the farm family, the farm family's human capital and their use of innovations, particularly key cropping innovations, have significant beneficial impacts on farm performance. The farmer's skills in time and organisational management, their engagement in business planning and the unique environmental characteristics of the farm also significantly and positively influence farm performance.     

Effects of Crop Prices,Nuisance Costs,and Wetland Regulation on Saskatchewan NAWMP Implementation Goals

Current Saskatchewan wetland regulation may be insufficient to meet North American Waterfowl Management Plan (NAWMP) preservation and restoration goals in a climate of increasing demand for grains and nuisance costs. Therefore, the purpose of this paper is to ascertain the effects that crop prices, nuisance costs, and alternate wetland regulation have on these goals. An integrated geographic information system and economic farm‐level model that assesses the net present value of drainage projects in the Whitesand River Watershed is employed. If prices eventually reach historical highs observed in the early 1970s, more than 85% of the wetland area in the study area could be drained, making NAWMP goals impossible to achieve. In this scenario, nuisance costs have little effect on drainage outcomes because they are dwarfed by the magnitude of agricultural revenue. If prices remain at the current higher levels observed from 2007 to 2012, the use of a binding permit could help achieve NAWMP goals. In this case, nuisance costs play a large role in determining the drainage of marginal, comparatively larger wetlands. If prices return to the recent lower levels observed from 1999 to 2006, current Saskatchewan regulation is sufficient. In this scenario, agricultural returns are low and nuisance costs are not high enough to cause wetland drainage. Both wetland regulation and nuisance costs can play an important role in agricultural wetland drainage, but that role depends critically upon the price of agricultural products.     

The role of family life-cycle events on persistent and transient inefficiencies in less favoured areas

Family farms dominate less favoured areas (LFAs) within Europe, and family life-cycle conditions, such as succession and retirement, affects how these farms adapt to changing circumstances. Past studies of on-farm technical efficiency have not directly addressed these conditions, but they may explain why some farms are more efficient than others, especially as the farm family model dominates most farming systems. Motivated by the UK's withdrawal from the EU and the debate around establishing replacement support policies, we apply a multi-step model to measure both transient and persistent inefficiencies using a panel of LFA cattle and sheep farms in Scotland over the period 2003–2020. We find a greater prevalence of persistent compared to transient inefficiency, which suggests that structural problems still exist. Farms with planned succession are found to have higher persistent efficiencies, whereas farmers nearing retirement have lower levels. Other factors, such as dependence on subsidy, off-farm activity and classification as severely disadvantaged tend to compound these lower efficiencies. We argue that life-cycle conditions should not be ignored in studies of farm technical efficiency. Within the scope of framing a new agricultural policy for UK administrations, these results inform the debate on support for LFAs, as well as the promotion of support towards generational renewal to ease transition across farm family life-cycle events.     

Intervention bias in agricultural policy

This paper re-examines the motivation for government intervention in agriculture to support farm prices and incomes. A model is outlined in which the government has a preference for higher farm incomes but fails to provide farmers with the socially optimal level of price support, even when one accepts the government's income redistribution goals as a valid reflection of social preference. It is shown that agricultural policy has an intervention bias: government price supports generally are higher than would be socially optimal. The source of the intervention bias is a time inconsistency in optimal agricultural policy formation, caused by the government's inability to precommit to a rule for setting future price support levels. Simulation results indicate that in some circumstances the intervention bias in agricultural policy can be substantial.     

Nonfarm employment,agricultural intensification,and productivity change: empirical findings from Uganda

This article uses panel data from the Living Standards Measurement Study‐Integrated Surveys on Agriculture for Uganda to assess the farm‐level effects of nonfarm employment on agricultural intensification and productivity change. A sample selection model is used to account for both unobserved heterogeneity and potential simultaneity between agricultural production and nonfarm income. Results show that nonfarm employment can have differential impacts on farm technology intensity and productivity. Nonfarm income is found to have a positive impact on farm hired labor and improved seed intensity; a negative effect on on‐farm family labor use; and no significant impact on fertilizer, soil water management, and joint use of farm technologies. The econometric evidence also indicates that agricultural productivity declines as nonfarm income increases. Taken together, our findings reveal important trade‐offs between nonfarm employment and income and farm productivity growth under smallholder agriculture. The results indicated that targeted policies are required to reduce these potential trade‐offs between nonfarm employment and agricultural intensification and productivity change.