Estimating the causal effect of improved fallows on farmer welfare using robust identification strategies in Chongwe - Zambia

Agricultural technological improvements are crucial to increase on farm production and thereby reduce poverty. However the use of improper identification strategies on the impacts of improved technologies on farmer welfare could potentially pose a threat to good practice agricultural policy making. In this study, propensity matching strategies and endogenous switching regression were used to test whether an improved fallow, a soil fertility improving technology that passed the requirements for a high impact intervention based on non randomised impact assessment methodologies could still pass this test. Using data from 324 randomly surveyed households in Chongwe district of Zambia, the rigorous econometric methods confirmed the positive impact of improved fallows on household maize yields, maize productivity, per capita maize yield and maize income. Conflicting results were obtained when a broader welfare indicator—per capita crop income, was considered. Whereas the non-randomised and kernel matching methods showed that per capita crop incomes were significantly higher for the adopters than for the non adopters, the causal effect of improved fallows on this variable was non significant when nearest neighbour matching strategy and the more robust endogenous switching regression were used. It was concluded that the technology improves welfare through increased maize and hence increased food security, and through incomes from the maize crop. The maize income derived from improved fallows were however not sufficient enough to drive the general crop income to significantly higher levels. The need to diversify the use of improved fallows on high valued crops was recommended while the importance of using better and more robust methodologies in evaluating impact of interventions was emphasised.Collaborative Masters in Applied Agricultural Economics (CMAAE), PhD Fellowship programme and the Centre for Environmental Economics Policy in Africa (CEEPA)http://link.springer.com/journal/10457hb201

Improved fallows in Eastern Zambia: history, farmer practice and impacts

"The decline in soil fertility in smallholder systems is a major factor inhibiting equitable development in much of sub-Saharan Africa. Some areas fallow in order to strength soil fertility for later planting, but as populations increase, demand follows and continuous cropping becomes the norm and there is a reduction in yields. This case study summarizes the development of improved tree fallows by researchers and farmers in eastern Zambia to help solve the problem of poor soil fertility. Many farmers are finding that by using improved fallows, they can substitute relatively small amounts of land and labor for cash, which they would need to buy mineral fertilizer. The study has three phases: the historical background (phase 1); an assessment of problems, description of the technology, and how it was developed (phase 2); and how the improved fallows practices were disseminated and spread (phase 3). This paper will describe each phase, the goals, and results." Authors' AbstractSouthern Africa, africa south of sahara, Crop yields,

The hedgification of maizescapes? Scalability and multifunctionality of Jatropha curcas hedges in a mixed farming landscape in Zambia

We argue that reading the local agricultural landscape is a prerequisite to understanding the plausible local impacts of external drivers for change, such as the introduction of new crops and technologies. Initially driven by a desire to understand the potential for small-scale farmers to produce jatropha biodiesel in a sustainable way, we started to examine how farmers related to trees in different parts of the agricultural landscape. This provided us with insights into small-scale processes of land enclosure and conversion, which indicate that agricultural intensification is taking place. We learned that although the landscape could in theory accommodate a lot of jatropha hedges around existing (maize dominated) arable land, farmers were only creating hedges around new fields, carved out in the grazing commons. Already well established within the settlement, jatropha can produce a range of different ecosystem services. However, our case study suggests that scalability is problematic: cultural ecosystem services can be provided at very limited levels of production; supporting ecosystem services require a certain scaling up of production; and provisioning ecosystem services, like biofuels, would require production to be increased well beyond any synergies with ongoing tree plantings or land conversion processes

Econometric analysis of the factors that affect adoption of conservation farming practices by smallholder farmers in Zambia

Abstract Despite the efforts to promote adoption of conservation farming (CF) by public and private organizations, the adoption rate among Zambian smallholder farm households has been low. This study used nationally representative data to identify the factors that affect adoption of CF by smallholder farm households in Zambia. Propensity Score Matching (PSM) was employed to help match the adopters and non-adopters of CF based on the distribution of their similar observable characteristics upon which a separate logistic model was applied. The logistic regression analysis showed that age of the household head; access to loans; labour availability; in-kind income and location of the households in agro-ecological regions (AER) I and II significantly increases the odds of adoption of CF. Based on these findings, it is recommended that promotion of adoption of CF practices should be directed towards smallholder farm households in AER I and II and those in remote areas which are less accessible by roads. This could be complemented by improving the road infrastructure so that smallholder farmers in such areas would not only have access to agricultural loans but also be in contact with relevant extension organizations that promote CF

Robust strategies to isolate the causal effect of improved fallows on farmer welfare and onfarm environmental quality in Zambia

This study attempts to explain the inability of resource constrained farmers in Zambia to invest in soil fertility enhancing improved fallows, a sustainable land use practice developed by the World Agroforestry Centre (ICRAF) in the 1980s. Although several studies in the laboratory and field have shown that improved fallows positively impact on farmers’ welfare, the reliability of such conclusions comes into question given their use of improper identification strategies. Secondly, although there is general consensus that improved fallows additionally co-produce environmental services, the literature acknowledges that such services are not only imprecisely defined but also rarely quantified. Most estimates for environmental services have been confined to controlled field trials and laboratory experiments. Consequently, this research was designed to answer the following questions: 1) Would the use of randomisation procedures to estimate impact provide additional support to the foregone conclusions by most literature regarding the positive impact of improved fallows on farmer welfare? 2) Studies from on-station experiments show that improved fallows provide environmental services; do such conclusions hold for improved fallows planted on-farm where the near ideal experimental conditions are not guaranteed? A structured questionnaire was used to interview 324 randomly selected small scale farmers in Chongwe district of Zambia between November and December 2011. The data was analysed using well-grounded and robust matching and switching regression counter factual analysis tools. The rigorous econometric methods confirmed the positive impact of improved fallows on household maize yields, maize productivity, per capita maize yield and maize income. Insignificant impact results were however obtained when broader welfare indicators – overall per capita, crop income and value of crop production were considered. The study attributes these later results to two possible areas; first, most of the maize sold that contributes to crop income may be coming from other input sources such as the inorganic fertiliser that is common in the study area. Second, the non-use of the technology on cash crops (for example cotton) in subsequent periods after a year or two of maize cropping reduces the technology’s contribution to the households’ cash crop income portfolio. Had the study only used maize income or value of maize income to measure overall crop income (or value of crop production), or had it just made a simple comparison between adopters and non adopters, the likelihood of not finding any insignificant results on the efficacy of improved fallows would have been high. The study thus concludes that the use of improved fallows should be diversified to cover the entire cash crop portfolio especially a year or so after maize cropping when most of the nitrogen supplied by technology has been used up. More importantly, the study recommends use of better and more robust methodologies in evaluating impact of interventions. The positive effects of improved fallows on on-farm environmental quality, controlling for farmers’ biophysical and socio-economic characteristics were confirmed. Estimates from OLS regression, matching and the more robust endogenous switching regression showed that the technology had a significant causal effect on households’ consumption of fuel wood obtained from natural forests. The technology can provide up to 1,086 kg or about 51% of annual household fuel wood requirements in the year the fallows are terminated. This amount is substantial enough to make a positive contribution towards reducing encroachment on public forests and thus control the rate of deforestation. In addition to promoting the technology for soil fertility improvement (the role which is widely accepted by the farmers), explicit extension messages conveying the technology’s capacity to provide various products that contribute to farmer welfare as well as provide on farm environmental quality should be made available.Thesis (PhD)--University of Pretoria, 2014.lk2014Agricultural Economics, Extension and Rural DevelopmentPhDUnrestricte

Understanding the Trade-Offs Between Environmental Service Provision through Improved Fallows and Private Welfare Using Stated Preference Approach: A Case Study in Chongwe - Zambia

The trade-offs between environmental service (ES) provision through the uptake of improved fallows and private farmer welfare losses have rarely been evaluated. Unlike inorganic fertiliser, improved fallows provide ES in addition to improving the soil fertility. This study used contingent valuation methodologies to evaluate willingness to provide ES through improved fallows among 324 farmers in Chongwe district of Zambia. Given scenarios that improved fallows, unlike inorganic fertiliser, help in mitigating soil erosion and water pollution, more than 70% of the farmers were willing to supply these services through the technology. The willingness to be pro-fertiliser oriented was positively associated with cropped land sizes and soil fertility challenges and negatively associated with total farm size. In addition, for users of improved fallows, increases in per capita income increased the probability of willingness to embrace fertiliser. Group membership decreased the probability for the users’ willingness to embrace fertiliser. For the non-users, the probability of joining the association that would ensure blockage of an improved fallow policy decreased with maize productivity. For the few farmers, there was no significant difference in the willingness to pay (WTP) (t = 1.546, p = 0.136) to ensure availability of fertiliser or blocking a policy compelling uptake of improved fallows between the users (WTP = K1, 050,000, US$1 = K5, 000) and non-users (WTP= K1, 380,000) of the technology. The trade-off between ES provisions through improved fallows and loss in immediate private welfare by not embracing fertiliser was similar across the technology’ users divide. Therefore a payment for environmental services policy could target the farmers as a homogenous group

Estimating the causal effect of improved fallows on farmer welfare using robust identification strategies in Chongwe - Zambia

Agricultural technological improvements are crucial to increase on farm production and thereby reduce poverty. However the use of improper identification strategies on the impacts of improved technologies on farmer welfare could potentially pose a threat to good practice agricultural policy making. In this paper, propensity matching strategies and endogenous switching regression were used to test whether an improved fallow, a soil fertility improving technology that passed the requirements for a high impact intervention based on non randomised impact assessment methodologies could still pass this test. Using data from 324 randomly surveyed households in Chongwe district of Zambia, the rigorous econometric methods confirmed the positive impact of improved fallows on household maize yields, maize productivity, per capita maize yield and maize income. Conflicting results were obtained when a broader welfare indicator – per capita crop income, was considered. Whereas the non-randomised and kernel matching methods showed that per capita crop incomes were significantly higher for the adopters than for the non adopters, the causal effect of improved fallows on this variable was non significant when nearest neighbour matching strategy and the more robust endogenous switching regression were used. It was concluded that the technology improves welfare through increased maize and hence increased food security, and through incomes from the maize crop. The maize income derived from improved fallows were however not sufficient enough to drive the general crop income to significantly higher levels. The need to diversify the use of improved fallows on high valued crops was recommended while the importance of using better and more robust methodologies in evaluating impact of interventions was emphasised

Impact of Urban Agriculture on Household Income in Zambia: An Economic Analysis

The study aimed to empirically determine the impact of urban agriculture on household income in Zambia. The analysis was based on the 2007/2008 Urban Consumption/ Expenditure secondary data collected in Kitwe and Lusaka districts, with a total sample size of 2,682 urban households. The propensity score matching approach is used to estimate the impact of urban agriculture on household income since the method takes into account the systematic differences in socio-economic characteristics between the urban agriculture practicing and non-practicing households by matching from both groups with similar characteristics. Results indicate that urban agriculture has a significant positive effect on household income. The income of households that practiced urban agriculture increased by 13.7% to 19.1%. It implies that urban agriculture has the potential to improve household livelihood through enhanced income