Testing for allocation efficiencies in water quality tenders across catchments,industries and pollutants: a north Queensland case study*

The design of competitive tenders to purchase environmental services requires judgements to be made about the funding scale and tender scope, with the latter incorporating considerations of geographic area, industries involved and the types of environmental outputs required. Increasing the scale and scope of tenders increases the likelihood that a larger range of proposals will be proposed and cost‐effective ones selected. However, the use of larger and more broadly scoped tenders may reduce landholder participation and increase asking bids. In the study reported here, these issues have been tested with a single water quality tender run in north‐eastern Australia in 2007 and 2008. Post hoc tests and workshop exercises show that while larger‐scale and scope tenders can generate efficiency gains, care has to be taken to maintain participation and avoid higher bid levels.     

Empirical analysis of corn and soybean basis in Canada

The article examines the factors affecting the basis for corn and soybeans using several time-series techniques to account for potential structural breaks, seasonality, residual serial correlation and structural breaks, as well as potential endogeneity and nonstationarity. The spatio-temporal empirical framework is based on storage and trade theories which assume the relationship between nondelivery location’s spot price and futures price of a storable commodity depends on opportunity cost of capital, warehousing costs, a convenience yield and shipping costs. The interest rate effect is strong for both crops with shipping costs also affecting soybean basis and own inventory levels positively correlated with corn basis. The effect of the wedge between the price of carrying physical grain and the maximum storage rate on basis is positive for both crops. The empirical results, which are robust to multiple estimators, provide stronger evidence of a structural break for the soybean basis than for the corn basis.     

城市污泥堆肥中复合微生物接种的研究进展

堆肥是污泥资源化最有效的途径之一,主要依靠微生物的新陈代谢活动来实现。接种复合微生物能够调节堆肥的菌群结构、延长高温期,提高物料降解速度,保证堆肥无害化。总结了复合微生物接种对城市污泥堆肥的影响,并提出污泥堆肥实践的研究重点。     

Estimating shadow price for symbiotic nitrogen and technical efficiency for legume‐based conservation agriculture in Malawi

Determining the value of legumes as soil fertility amendments can be challenging, yet this information is required to guide public policy and to incentivise prescribed land‐management practices such as conservation agriculture. We use a directional input distance function (DIDF) to estimate shadow prices for symbiotic nitrogen and the technical efficiency for mixed maize‐legume production systems in Malawi. The shadow prices reflect the trade‐off between fertiliser nitrogen and symbiotic nitrogen required to achieve a given quantity of output. Our results reveal considerable technical inefficiency in the production system. The estimated shadow prices vary across farms and are, on average, higher than the reference price for commercial nitrogen. The results suggest that it would be beneficial to redesign the current price‐support programs that subsidise chemical fertilisers and indirectly crowd‐out organic soil amendments such as legumes.     

Examining the relationship between farm size and productive efficiency: a Bayesian directional distance function approach

Achieving sustainable food security and increased farm income will depend on how efficient production systems are in converting available inputs to produce outputs. Using data from Malawi, we estimate a Bayesian directional technology distance function to examine the relationship between farm size and technical efficiency. Our results support the existence of an inverse relationship between farm size and productive efficiency, where small farms are more efficient than large farms. On average, farms exhibit inefficiency levels of 60%, suggesting that productivity could be improved substantially. Improving productive efficiency and food security will require farms to operate in ways where the size of cultivated area is matched by nonland production inputs such as labor, fertilizer, and improved seeds. The results highlight the need for policies that could incentivize farmers to adopt productivity‐enhancing technologies and, where possible, to allocate excess land to lease markets.     

The Impact of Local Ethanol Production on the Corn Basis in Ontario

This paper investigates the factors affecting the corn basis in Ontario with particular emphasis on the effect of ethanol production given the projected detrimental effect its expansion could have on the red meat sector. We estimate a location‐specific and panel vector error correction models (VECM) for seven elevators in Ontario from 2006 to 2013. We find a long‐run equilibrium relationship exists between the basis and factors affecting local supply and demand including ethanol capacity and that the direction of causality is from these factors to changes in corn price. A one‐time increase in ethanol capacity of 100 million liters is projected to increase the basis by approximately 30 cents per bushel within two years. However, the impact is insignificant for elevators located in the livestock‐intensive regions of the province. The demand for corn as livestock feed is a determinant of the local corn price for all elevators. The decline in the number of hogs and beef cattle along with the 50% increase in corn supply have resulted in the observed decline in the local corn price despite the significant increase in demand from ethanol. L'impact de la production locale d′éthanol sur le prix de base du maïs en Ontario Cet article cherche à comprendre les facteurs ayant un effet sur le prix de base du maïs en Ontario, en particulier sur les effets de la production d′éthanol étant donné les effets négatifs attendus sur le secteur de la viande rouge causés par son expansion. Nous estimons des modèles vectoriels à correction d'erreurs (MVCE) à emplacements précis et panel entre 2006 et 2013, pour 7 silos‐élévateurs en Ontario. Nous constatons une relation d′équilibre à long terme entre le prix de base et les facteurs ayant un effet sur l'offre et la demande locale incluant la capacité pour l′éthanol. Nous constatons aussi que le sens de la causalité passe de ces facteurs aux changements du prix du maïs. L'on s'attend à voir une augmentation d'environ 30 cents du prix de base du boisseau suivant l'augmentation unique de 100 millions de litres de la capacité d′éthanol. Par contre, l'impact est négligeable pour les silos‐élévateurs situés dans les régions d′élevage intensif de la province. La demande pour le maïs comme aliment pour le bétail est un facteur déterminant du prix local du maïs pour tous les silos‐élévateurs. Le déclin du porc et des bovins ainsi que l'augmentation de 50 % de l'offre de maïs ont mené à la diminution notée du prix du maïs local malgré l'augmentation significative de la demande pour l′éthanol.     

Choice of Rice Production Practices in Ghana: A Comparison of Willingness to Pay and Preference Space Estimates

Rice has been identified as an important food security crop in Ghana. However, there is a production deficit and new technologies to reduce the deficit are not widely adopted. Although poor adoption by farmers’ is often linked to constraints such as access to information, farmers’ perceptions of the technologies are also important. We apply an advanced discrete choice experiment to evaluate farmers’ preferences for rice production practices. Specifically, we generate willingness to pay (WTP) estimates using willingness to pay space (WS) and compare these with values from the indirect or preference space (PS) method. Our modelling also accounts for the effects on WTP estimates of farmers’ stated attribute importance (SAI) information. Empirical results from WS and PS models reveal that on average, farmers value higher yields and are negatively affected by higher risk of crop failure and labour requirements. Comparing the performance of the two models, we find the WS model provides a superior fit to our data and reduces the likelihood of producing implausible WTP estimates. Further, SAI inclusion did not produce much variation in our WTP estimates.     

Does It Pay to Increase Competition in Combinatorial Conservation Auctions?

Conservation auctions allow landholders to propose conservation projects and associated payments (bids) for consideration by a conservation agency. Recently, the application of iterative combinatorial auction designs has been proposed to improve outcomes of conservation auctions. In combinatorial auctions, landholders are allowed to offer projects each of which involves activities aimed at providing one or multiple services. An iterative format allows bidders the opportunity to gradually explore the type of projects they want to offer, with this process being facilitated through price feedback provided based on intermediate auction round results. Auction designs vary with the type of feedback and respond differently to market conditions. At present there is a lack of information about their performance in markets with varying degrees of competition (in terms of number of bidders and level of target). Therefore, using an agent‐based simulation model, we evaluate a number of iterative auction designs. We observe that a higher degree of competition leads to a higher auction efficiency. In a high competition environment, efficiency outcomes tend to be less sensitive to auction design choices. Therefore, an auctioneer could enjoy freedom in design choice if adequate competition could be ensured. In weak competition environments, however, some auction designs perform better than others.     

Endogenizing the Planning Horizon in Urban fringe agriculture

To evaluate the nature of farm operation longevity in urban fringe agriculture, this paper develops a model that endogenizes planning horizon and estimates an empirical model whereby anticipated longevity in farming is regressed against farm, farmer, regulatory and land market related variables. The results suggest that the length of the planning horizon is directly related to farm profitability and confirm the impermanence syndrome hypothesis that land values are inversely related to the planning horizon. Contrary to farmers’ claims that periodic land disposal provides an internal source of credit to support long-term viability, the disposition of portions of the farmland is found to shorten the planning horizon. Innovative farmers are found to have longer planning horizons while experiences with Right-to-Farm conflicts are found to result in decreased planning horizon. Given the expected continual increase in land values and the growing physical closeness of farmers to their non-farm neighbors, significant concerns remain about the long-term survivability of urban fringe farmers. This study suggests the importance of considering farmers’ planning horizon as a key component in farmland retention programs.     

A Luenberger soil-quality indicator

This paper discusses how a quality indicator can be constructed as a Luenberger indicator using directional distance functions. This leads to a suggested formula for aggregating individual soil quality attributes into an indicator. The method is illustrated using crop trials data from Western Australia. The approach presented is theoretically consistent and may provide a better alternative to many of the ad hoc procedures used to construct soil-quality indexes in the soil science literature. Our approach also addresses shortcomings related to quality indicators previously proposed in the productivity literature using Malmquist indices.