Risk Preferences as Determinants of Soil Conservation Decisions in Ethiopia

Soil degradation is one of the most serious environmental problems in the highlands of Ethiopia. The prevalence of traditional agricultural land use and the absence of appropriate resource management often result in the degradation of natural soil fertility. This has important implications for soil productivity, household food security, and poverty. Given the extreme vulnerability of farmers in this area, we hypothesized that farmers’ risk preferences might affect the sustainability of resource use. This study presents experimental results on the willingness of farmers to take risks and relates the subjective risk preferences to actual soil conservation decisions. The study looks at a random sample of 143 households with 597 farming plots. We found that a high degree of risk aversion significantly decreases the probability of adopting soil conservation. This implies that reducing farmers’ risk exposure could promote soil conservation practices and thus more sustainable natural resource management. This might be achieved by improving tenure security, promoting access to extension services and education, and developing off-farm activities that generate income.adoption, Ethiopia, risk preference, soil conservation

An Application of Mixed Logit Estimation in the Analysis of Producers’ Stated Preferences

This paper analyzes Colorado Corn producers’ preferences over both private- and environmental public-good production system attributes. Current production practices are characterized by intensive water and chemical use, resulting in non-point source pollution to water bodies as well as soil erosion problems. Data from a stated preference survey are employed to analyze key attributes of experimentally configured irrigation systems, proposed as alternatives to current practices. Panel mixed logit estimations find positive preferences for profit, risk reduction, and, importantly, systems with less environmental impact in terms of nitrate leaching and soil erosion. The results also find presence of significant preference heterogeneity and a complementary relationship between the two environmental attributes. Analysis of this kind can be used by policy makers to predict behavioral responses associated with introduction of new technologies, or to assess welfare implications of agricultural policy changes and stricter environmental regulations.Agricultural production, profit-maximization, environment, mixed logit, stated preference, attribute part-worth, nitrate leaching, soil erosion, risk, Crop Production/Industries, C10, D62, Q12, Q15, Q51,

Economics of soil and water conservation

The Ethiopian highlands, inhabited by the vast majority of the Ethiopian human and livestock populations, are under continuous threat from soil erosion. Land degradation induced by soil erosion is considered to be among the major factors responsible for the recurrent malnutrition and famine problems in Ethiopia. Conservation efforts during recent decades have succeeded neither in triggering voluntary adoption of conservation practices nor in mitigating soil erosion problems. The purpose of this thesis is, therefore, to understand the socio-economic aspects underlying soil and water conservation decisions in the context of subsistence farmers in the Eastern Highlands of Ethiopia. In articles I, III, and IV, the farmers’ decision problem is modeled as a utility maximization problem, and econometric models are used to link the statistical model of observed data and the economic model. Stochastic dominance criteria are used, in article I, to determine whether adoption of a conservation practice results in higher expected grain yield and income and/or reduced variability. Limited dependent variable econometric models are used in articles III and IV in order to determine factors that influence farmers’ decisions on soil and water conservation, and their preference for types of development intervention. In article II, the decision problem is modeled as an intertemporal net benefit maximization problem, and a dynamic programming optimization model is applied to determine the optimal path of investment in soil and water conservation. Findings in article I suggest that conservation results in higher expected grain yield and income, but does not support the hypothesis that conservation unambiguously results in less variability than no-conservation. In article II, it is shown that the optimal path of investment in soil and water conservation depends on the discount rate and grain prices. The results also suggest that erosive agricultural practices yield higher return in the short-term, whereas conservation yields a higher and sustainable return in the long-term. The need to design incentive mechanisms that encourage farmers to have a longer planning horizon are among important suggestions proposed in articles I and II. Results, in article III, suggest that specific physical conditions of plots and socioeconomic characteristics of farm households influence the soil and water conservation decision behavior of farmers. Article IV suggests that the perceived priority of farmers with regard to agricultural problems and socio-economic characteristics, determines their preference for the type of development intervention. The results also suggest that there exists a complementarity between different interventions and hence a need to address them simultaneously to ensure a higher return from interventions. An important lesson to be drawn from articles III and IV is that differences in farming conditions and complementarities between policy programs need to be noted in any intervention program

Effect of calcified seaweed application on grazing preference by dairy cows

This report was presented at the UK Organic Research 2002 Conference. An experiment was carried out to determine whether the application of calcified seaweed improved the preference of organic dairy cows for pasture. Two treatments were applied in May 2001; calcified seaweed applied at 625kg/ha (C+) or no application (C-). The number of cows grazing within individual plots was recorded in July and August 2001. A significantly higher number of cows were recorded in C+ plots than in C- plots. This effect could not be explained by changes in soil or herbage analysis. There may have been additional unknown effects of the C+ treatment on herbage palatability but the results may also have been influenced by external factors such as the location of water troughs

Lime stabilisation for earthworks: a UK perspective

Lime stabilisation is a versatile technique applied during earthworks operations. Modern soil recycling units are much more efficient at pulverising fill material and intermixing the added binder/water than machinery available 20 years ago. While supplier innovation adds flexibility to the site working method, specifications have not been sufficiently updated to permit optimal application. This review paper details the physico-chemical changes instigated through the lime-clay soil reaction, updating previous reviews. It aims to assist scientific debate, current practitioners and future specification changes. For example, the application of the minimum 24 h mellowing periods (mandatory to UK specifications) with high reactivity, quicklime powders is concluded to cause increased air voids in the compacted fill. Increased air voids are associated with reduced long-term strength and potential volume change from water ingress, which is of particular concern for sulfate swelling. Shorter mellowing periods and/or use of hydrated lime may lesson this issue; however, a 'one size fits all' approach is discouraged in preference to site-specific methodologies refined to suit the fill material and project requirements. The discussion also summarises working methods which may lower the risk of sulfate swell and defines areas requiring further practical research

Differing preferences of Antarctic soil nematodes for microbial prey

We tested the preferences of three nematode taxa, Geomonhystera villosa, Plectus spp. and Teratocephalus spp., extracted from moss at Signy Island in the Maritime Antarctic, for two microalgae, three microfungi and six heterotrophic bacteria, each also from soils at Signy Island. Choice test experiments on water agar medium, in which nematodes were enumerated in wells containing microbes at 24 and 48 h, indicated that there were differing preferences between nematodes for distinct prey. G. villosa was significantly attracted to the alga Chlorella cf. minutissima and the fungus Mortierella hyalina, and was more attracted to all algae and fungi than either of the other two nematodes. Both G. villosa and Teratocephalus spp. were attracted to an actinobacterium. Plectus spp. were significantly attracted to the alga Stichococcus bacillaris and bacteria with close taxonomic affinities to Arthrobacter, Pseudomonas and Polaromonas. Experiments using 0.5 μm diameter fluorescent beads indicated significantly increased ingestion by nematodes in the presence of each of these microbes compared with controls, except by Plectus spp. in the presence of S. bacillaris. We conclude that complex trophic interactions may occur in apparently simple Antarctic soil food webs

The consistently superior quality of carrots from one organic farm in Austria compared with conventional farms

The aim of this 5 year investigation was to compare quality parameters of differently cultivated carrots of the same cultivar grown in the same region as well as to compare the relevance of different methods of analysis to differentiate between these products. The following quality tests were applied: • Sensory tests (all harvests) • Food preference tests with laboratory rats (all harvests) • Decomposition tests (all harvests) • P-value determination (all harvests) • Single-Photon-Counting (1999) • Chemical analysis of the main components (1998 and 1999) It could be shown that carrots (var. Tarvil) grown using an organic farming method were significantly preferred by humans and laboratory rats, lost significantly less dry matter during decomposition, had lower P-values, indicating better bioelectrical properties, revealed a significantly better capacity to store biophotons, but showed no conclusive differentiation concerning their main components. Holistic methods were well qualified to distinguish organic from conventional carrots on significant levels

Efficiency analysis of Policies against desertification by applying DEA: a case study in the river Guadalentin catchment (Almeria, Spain)

This paper deals about an attempt to evaluate the different policies against desertification carried out during a twenty five year period (1978-2003) in the eight municipalities which compound the river Guadalentín catchment (Murcia, Spain). The approach is based on DEA and the European Environmental Agency indicator studies, the former to measure the efficiency and the second to select the best environmental indicators. The analysis has been reiterated with three different sets of outputs related to the different levels and aspects of the desertification process- from the merely soil losses to the overall desertification process in which population losses are considered. As a result a set of efficiency indexes has been obtained for each municipality, which show clearly the contribution of each action against desertification. These results are very valuable to establish future long term desertification policies in similar territories

UK consumer reactions to organic certification logos

Purpose - This paper considers the question of whether UK consumers recognise and trust organic certification logos and whether the presence of these logos on a product increases consumer willingness to pay for that product. Methodology/approach - To ascertain the reaction of UK consumers to organic certification logos commonly used in the UK, this study makes use of three methods: focus groups, a consumer survey and a willingness to pay experiment (choice experiment). Findings - These three approaches reveal that UK consumers associate certain benefits with organic foods but are generally unaware of how the industry is regulated. With regards to trust of the logo, the standards they think underlie the logo and the inspection system that they think is associated with the logo, UK consumers rate the Soil Association and Organic Farmers and Growers logos more highly than the EU logo or products labelled with just the word “organic”. They appear willing to pay a premium for the additional assurance that these two logos provide, suggesting that where they are recognised, certification logos are valued. Originality – To the authors’ knowledge, no previous studies exist on whether UK consumers recognise and trust different organic certification logos. These findings show that where such logos are recognised they can help to give some assurance to the UK consumer and this is reflected in a willingness to pay a premium for foods labelled with the Soil Association and Organic Farmers and Growers certification logos as opposed to no logo or the (less well known) EU logo