Temporary migration decisions and effects on household income and diets in rural Bangladesh

Temporary migration is a widely observed phenomenon among poor rural households, mostly related to agricultural seasonality. However, household preferences for temporary migration in comparison to longer-term migration, and the differential effects of these migrations on household livelihoods are not yet well understood. Here, we use survey data collected in northern rural Bangladesh to analyze determinants of households’ choice between temporary and longer-term migration, and their comparative effects on various livelihood indicators, with a particular focus on agricultural lean periods. Issues of selection bias and endogeneity are addressed with Heckman selection models and instrumental variables. We show that temporary migration is more common than longer-term migration, partly determined by family demographic and farm-labor constraints. Although longer-term migration has larger positive effects on household income, temporary migration has larger positive effects on food consumption and dietary quality during lean periods. These results suggest that temporary migration is an important mechanism for the rural poor to smooth consumption and deserves more attention by researchers and policy-makers

Analysis of policies to promote weatherization of homes on Martha's Vineyard

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1981.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH.Bibliography: leaves 99-101.by Amy Faye Philipson.M.C.P

Rainfall variability and groundwater availability for irrigation in Sub-Saharan Africa: evidence from the Niayes region of Senegal

Recent research on climate change, within the context of Sub-Saharan Africa, has shown the vulnerability of groundwater resources to climate change and variability. In Senegal, agriculture is among the most important users of groundwater resources, especially in the northern coastal area called ‘Niayes’ where farmers practice irrigated agriculture and use almost exclusively the quarternary sand aquifer for their irrigation needs during the dry season – which is the main growing period. However, in Senegal, irrigated agriculture, particularly that of horticultural crops, mostly grown in the Niayes, has attracted less research attention in terms of studies focused on climate change or variability, compared to staple-growing rainfed regions. In the Niayes region, farmers grow most of Senegal’s horticultural production. Combined with human use of water resources, climate variability may threaten future irrigation water availability in the area. This paper uses an integrated hydroeconomic model and a rainfall generator to evaluate the impact of rainfall variability on irrigation water availability and simulate its implications on producers’ responses and groundwater management policy measures. Results show that groundwater availability is diminishing over time, resulting in higher water table depth and smaller water withdrawals by farmers who will tend to decrease the area allocated to crops and favor the higher-valued crops. These trends are accelerated under a drier climate regime. A taxation policy to stabilize the aquifer would induce a reduction of the area under cultivation and have negative implications on revenues. Supply-side measures to enhance recharge may not be technically or financially feasible. This suggests that Senegal needs to develop groundwater management options that favor sustainable use of agricultural water resources without hindering national horticultural production

Rainfall variability and groundwater availability for irrigation in Sub-Saharan Africa: evidence from the Niayes region of Senegal

Recent research on climate change, within the context of Sub-Saharan Africa, has shown the vulnerability of groundwater resources to climate change and variability. In Senegal, agriculture is among the most important users of groundwater resources, especially in the northern coastal area called ‘Niayes’ where farmers practice irrigated agriculture and use almost exclusively the quarternary sand aquifer for their irrigation needs during the dry season – which is the main growing period. However, in Senegal, irrigated agriculture, particularly that of horticultural crops, mostly grown in the Niayes, has attracted less research attention in terms of studies focused on climate change or variability, compared to staple-growing rainfed regions. In the Niayes region, farmers grow most of Senegal’s horticultural production. Combined with human use of water resources, climate variability may threaten future irrigation water availability in the area. This paper uses an integrated hydroeconomic model and a rainfall generator to evaluate the impact of rainfall variability on irrigation water availability and simulate its implications on producers’ responses and groundwater management policy measures. Results show that groundwater availability is diminishing over time, resulting in higher water table depth and smaller water withdrawals by farmers who will tend to decrease the area allocated to crops and favor the higher-valued crops. These trends are accelerated under a drier climate regime. A taxation policy to stabilize the aquifer would induce a reduction of the area under cultivation and have negative implications on revenues. Supply-side measures to enhance recharge may not be technically or financially feasible. This suggests that Senegal needs to develop groundwater management options that favor sustainable use of agricultural water resources without hindering national horticultural production

Rainfall variability and groundwater availability for irrigation in Sub-Saharan Africa: evidence from the Niayes region of Senegal

Recent research on climate change, within the context of Sub-Saharan Africa, has shown the vulnerability of groundwater resources to climate change and variability. In Senegal, agriculture is among the most important users of groundwater resources, especially in the northern coastal area called ‘Niayes’ where farmers practice irrigated agriculture and use almost exclusively the quarternary sand aquifer for their irrigation needs during the dry season – which is the main growing period. However, in Senegal, irrigated agriculture, particularly that of horticultural crops, mostly grown in the Niayes, has attracted less research attention in terms of studies focused on climate change or variability, compared to staple-growing rainfed regions. In the Niayes region, farmers grow most of Senegal’s horticultural production. Combined with human use of water resources, climate variability may threaten future irrigation water availability in the area. This paper uses an integrated hydroeconomic model and a rainfall generator to evaluate the impact of rainfall variability on irrigation water availability and simulate its implications on producers’ responses and groundwater management policy measures. Results show that groundwater availability is diminishing over time, resulting in higher water table depth and smaller water withdrawals by farmers who will tend to decrease the area allocated to crops and favor the higher-valued crops. These trends are accelerated under a drier climate regime. A taxation policy to stabilize the aquifer would induce a reduction of the area under cultivation and have negative implications on revenues. Supply-side measures to enhance recharge may not be technically or financially feasible. This suggests that Senegal needs to develop groundwater management options that favor sustainable use of agricultural water resources without hindering national horticultural production

Investing in Risky Inputs in Senegal: Implications for Farm Profit and Food Production

While the productivity effects of the application of modern inputs, such as im- proved seeds or inorganic fertilizer, are well known, farmers in Sub-Saharan Africa tended to underinvest in purchased inputs. This underinvestment appears related to the unpredictable nature of agricultural production that is subject to risks and shocks. Farmers make production decisions before climatic and other shocks are realized. They, therefore, have no certainty about the outcome of their decisions. This makes investments in agricultural inputs very risky. This paper uses recent data for Senegal to identify the main drivers of the decision to purchase risky inputs (seeds and/or fertilizers), the level of investment and to quantify the impact of the use of risky inputs on household welfare. Using a Heck- man model, results show that the main drivers of the decision to purchase risky inputs include household composition, farmer organization, farm size, access to livestock income, and crop diversification. Drivers of the level of investment in risky inputs are gender, extension services, farm size, agricultural capital, and cropping patterns. Using an endogenous switching regression, we find a positive impact on the adoption of risky inputs on farm profit per hectare, and food available from production. The expected impact for non-adopters is found to be higher than that for adopters because they are involved in rice production (which is more responsive to inputs use) and in millet production (which is central for food security)

Ultrasound-Assisted Extraction of Polyphenols from Ginger (Zingiber officinale) and Evaluation of its Antioxidant and Antimicrobial Properties

In this present study, ultrasound-assisted solvent extraction conditions were optimized to develop a more efficient method that would result in maximum extraction of polyphenols from ginger. To achieve this optimal extraction process, a central composite design of response surface methodology was applied. A second-order polynomial equation was developed, indicating the effect of ginger concentration (400-1,200 mg/20mL solvent), solvent mixture composition (20-100%), temperature (30-70°C) and treatment time (10-30 min) on polyphenols extraction. The optimum parameters were found to be 1200mg of ginger prepared with 86% ethanol and sonication for 11 minutes at 65°C. The total phenolic and flavonoid content of ginger was found to be 1039.64 mg Gallic acid equivalent (GAE)/g and 492.57±3.5 mg Quercetin equivalent (QE)/g of ginger extract (dry weight), respectively. The ginger extract proved to have significant antioxidant capacity with a DPPH radical scavenging activity of 54.5% noted and further proved to have strong antimicrobial effects against Escherichia coli, Salmonella typhimurium, Bacillus cereus and Staphylococcus aureus with diameter of inhibition zone (DIZ) values of 14.49mm, 15.10mm, 16.74mm and 13.88mm recorded respectively, MIC values ranging from 3.75 – 7.5mg/ml and an extract concentration of 7.5mg/ml required to exert bactericidal effects against B.cereus and 15mg/ml for all other strains. All values obtained were comparable to that of synthetic preservatives sodium nitrite and sodium benzoate thus demonstrating the superior potential of this spice for future application as a natural food preservative