| 1. |
- Akpalu, Wisdom, 1968, et al.
(författare)
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Bio-economics of Conservation Agriculture and Soil Carbon Sequestration in Developing Countries
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Improvement in soil carbon through conservation agriculture in developing countries may generate some private benefits to farmers as well as sequester carbon emissions, which is a positive externality to society. Leaving crop residue on the farm has become an important option in conservation agriculture practice. However, in developing countries, using crop residue for conservation agriculture has the opportunity cost of say feed for livestock. In this paper, we model and develop an expression for an optimum economic incentive that is necessary to internalize the positive externality. A crude value of the tax is calculated using data from Kenya. We also empirically investigated the determinants of the crop residue left on the farm and found that it depends on cation exchange capacity (CEC) of the soil, the prices of maize, whether extension officers visit the plot or not, household size, the level of education of the household head and alternative cost of soil conservation.
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| 2. |
- Ekbom, Anders, 1963
(författare)
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Determinants of Soil Capital
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This paper combines knowledge from soil science and economics to estimate economic determinants of soil capital. Explaining soil capital facilitates a better understanding of constraints and opportunities for increased agricultural production and reduced land degradation. The study builds on an unusually rich data set that combines data on soil capital (represented by chemical and physical properties) and economic data on household characteristics, labour supply, crop allocation and conservation investments. The study yields both methodological and policy-relevant results. On methodology, the analysis shows that soil capital is heterogeneous with soil properties widely distributed across the farms. Likewise, farmers? investment decisions and soil management vary widely across farms. Hence simplifications of soil capital, which are common in the economics literature, may have limited validity. On the other hand, soil science research limited to soils? biological, physical and chemical characteristics fail to recognize that soil is capital owned and managed by farmers. They thus run the risk of omitting important socio-economic determinants of soil capital. They also exclude the possibility to explain some of the dynamics that are determined by its stock character. On policy, the study shows that farmers? soil conservation investments, allocation of labour, manure and fertilizer input, and crop choice indeed do determine variation in farmers? soil capital. Particularly strong positive effects on key soil nutrients (N,P,K) are observed for certain conservation technologies. Extension advice shows unexpectedly no significant effects on soil capital. The wide distribution of soil properties across farms reinforces the need to (i) tailor technical extension advice to the specific circumstances in each farm, and (ii) enhance the integration of farmers? knowledge and experiences, expert judgment and scientific soil analysis at the farm level.
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| 3. |
- Ekbom, Anders, 1963, et al.
(författare)
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Integrating Soil Science into Agricultural Production Frontiers
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This paper integrates soil science variables into an economic analysis of agricultural output among small-scale farmers in Kenya’s highlands. The integration is valuable because farmers’ choice of inputs depends on both the status of the soil and socio-economic conditions. The study uses a stochastic production frontier in which the individual farm’s distance to the frontier depends systematically on individual factors. We show the importance of including key soil properties and find that phosphorus has a negative output elasticity, suggesting that farms may be using the wrong fertilizer mix. Hence, the central policy implication is that while fertilizers are generally beneficial, their application needs to be based on better soil information. This highlights the importance of strengthening agricultural extension, increased access to markets, and more diversified supply of production inputs.
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| 4. |
- Ekbom, Anders, 1963, et al.
(författare)
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Muddy Waters: Soil Erosion and Downstream Externalities
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Soil erosion and fertilizer run-off cause serious flow externalities in downstream environments through-out the world. Social costs include e.g. loss of health, life and production due to pollution and eutrophication of freshwater resources, reduced life of hydro-power plants, increased turbidity, and degradation of coral reefs and marine resources. The key optimal control models on soil capital management omit downstream externalities and assume that the individual farmer and society share the same objective function. In the presence of externalities, there is a discrepancy. In this paper the social planner aims at maximizing the profits from agriculture subject to a soil dynamics-constraint and external damage costs caused by downstream contamination from soil and fertilizer leakage. These effects are not considered by the farmer. Comparative statics analysis shows that factors which promote a low discount rate (tenure security, access to credits, crop insurance etc.) will reduce soil erosion and nutrient leakage and promote accumulation of soil capital. Socially optimal subsidies for soil conservation not only will build-up soil capital and increase on-site crop production, but will also reduce nutrient leakage and soil loss. A charge on fertilizer would reduce fertilizer use and thus reduce the water pollution caused by leakage of inorganic nutrients. Based on our model results, combined with an extended discussion on policy instruments, we conclude that the government should try to provide incentives, not necessarily to stop soil loss per se (since the farmers will look after their own capital) but to avoid contamination of downstream environments, where the resource users have few opportunities to negotiate with the upstream farmers, who may even be unaware of the problems they cause.
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| 5. |
- Ekbom, Anders, 1963, et al.
(författare)
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Soil Properties and Soil Conservation Investments in Agricultural Production - a Case study of Kenya?s Central Highlands
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This paper integrates traditional economic variables, soil properties and variables on soil conservation technologies in order to estimate agricultural output among small-scale farmers in Kenya?s central highlands. The study has methodological, empirical as well as policy results. The key methodological result is that integrating traditional economics and soil science is highly worthwhile in this area of research. Omitting measures of soil capital can cause omitted variables bias since farmers? choice of inputs depend both on the quality and status of the soil capital and on other economic conditions such as availability and cost of labour, fertilizers, manure and other inputs. The study shows that: (i) models which include soil capital and soil conservation technologies yield a considerably lower output elasticity of farm-yard manure; (ii) mean output elasticities of key soil nutrients like nitrogen (N) and potassium (K) are positive and relatively large; (iii) counter to our expectations, the mean output elasticity of phosphorus (P) is negative; (iv) soil conservation technologies like green manure and terraces are positively associated with output and yield relatively large output elasticities. The central policy conclusion is that while fertilizers are generally beneficial, their application is a complex art and more is not necessarily better. The limited local market supply of fertilizers, combined with the different output effects of N, P and K, point at the importance of improving the performance of input markets and strengthening agricultural extension. Further, given the policy debate on the impact and usefulness of government subsidies to soil conservation, our results suggest that soil conservation investments contribute to increase farmers? output. Consequently, government support to appropriate soil conservation investments arrests soil erosion, prevents downstream externalities and assists farmers? efforts to increase food production and food security.
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| 6. |
- Slunge, Daniel, 1968, et al.
(författare)
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Can Strategic Environmental and Social Assessment of REDD+ Improve Forest Governance?
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Forest Carbon Partnership Facility has recently proposed the application of strategic environmental social assessment (SESA) for incorporating environmental and social considerations in the preparation of REDD+ initiatives. This paper discusses the potential contribution of SESA to REDD+ initiatives drawing on experiences from earlier attempts to large scale forestry sector reforms and a recent World Bank pilot program on strategic environmental assessment. The paper suggests that SESA can be a useful approach for strengthening institutions and governance needed for managing diverse environmental and social impacts related to REDD+. More specifically, SESA can enhance policy making and governance through raising attention to environmental and social priorities, strengthening constituencies for policy change and improving social accountability. In order for SESA to contribute to these outcomes it needs to be assured that broad national “ownership” is achieved and that it becomes part of a long-term policy learning process with repeated and sustained stakeholder interaction. Through strengthening constituencies in policy reform SESA can potentially reduce the risk of regulatory capture of REDD+ by vested interests and make institutional checks and balances more effective. An analysis of Kenya‟s process of preparing a national REDD+ strategy is used to illustrate our case in the paper.
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