The effect of nitrogen-fertilizer and optimal plant population on the profitability of maize plots in the Wami River sub-basin, Tanzania: A bio-economic simulation approach.

Maize (Zea mays L.) is the essential staple in sub-Saharan Africa (SSA) and Tanzania in particular; the crop accounts for over 30% of the food production, 20% of the agricultural gross domestic product (GDP) and over 75% of the cereal consumption. Maize is grown under a higher risk of failure due to the over-dependence rain-fed farming system resulting in low income and food insecurity among maize-based farmers. However, many practices, including conservation agriculture, soil and water conservation, resilient crop varieties, and soil fertility management, are suggested to increase cereal productivity in Tanzania. Improving planting density, and the use of fertilizers are the immediate options recommended by Tanzania's government. In this paper, we evaluate the economic feasibility of the improved planting density (optimized plant population) and N-fertilizer crop management practices on maize net returns in semi-arid and sub-humid agro-ecological zones in the Wami River sub-Basin, Tanzania. We introduce a bio-economic simulation model using Monte Carlo simulation procedures to evaluate the economic viability of risky crop management practices so that the decision-maker can make better management decisions. The study utilizes maize yield data sets from two biophysical cropping system models, namely the APSIM and DSSAT. A total of 83 plots for the semi-arid and 85 plots for the sub-humid agro-ecological zones consisted of this analysis. The crop management practices under study comprise the application of 40 kg N-fertilizer/ha and plant population of 3.3 plants/m2 . The study finds that the use of improved plant population had the lowest annual net return with fertilizer application fetching the highest return. The two crop models demonstrated a zero probability of negative net returns for farms using fertilizer rates of 40 kg N/ha except for DSSAT, which observed a small probability (0.4%) in the sub-humid area. The optimized plant population presented 16.4% to 26.6% probability of negatives net returns for semi-arid and 14.6% to 30.2% probability of negative net returns for sub-humid zones. The results suggest that the application of fertilizer practices reduces the risks associated with the mean returns, but increasing the plant population has a high probability of economic failure, particularly in the sub-humid zone. Maize sub-sector in Tanzania is projected to continue experiencing a significant decrease in yields and net returns, but there is a high chance that it will be better-off if proper alternatives are employed. Similar studies are needed to explore the potential of interventions highlighted in the ACRP for better decision-making.

Evaluation of new farming technologies in Ethiopia using the Integrated Decision Support System (IDSS).

This study investigates multi-dimensional impacts of adopting new technology in agriculture at the farm/village and watershed scale in sub-Saharan Africa using the Integrated Decision Support System (IDSS). Application of IDSS as an integrated modeling tool helps solve complex issues in agricultural systems by simultaneously assessing production, environmental, economic, and nutritional consequences of adopting agricultural technologies for sustainable increases in food production and use of scarce natural resources. The IDSS approach was applied to the Amhara region of Ethiopia, where the scarcity of resources and agro-environmental consequences are critical to agricultural productivity of small farm, to analyze the impacts of alternative agricultural technology interventions. Results show significant improvements in family income and nutrition, achieved through the adoption of irrigation technologies, proper use of fertilizer, and improved seed varieties while preserving environmental indicators in terms of soil erosion and sediment loadings. These pilot studies demonstrate the usefulness of the IDSS approach as a tool that can be used to predict and evaluate the economic and environmental consequences of adopting new agricultural technologies that aim to improve the livelihoods of subsistence farmers.

Integrating forest ecosystem services into the farming landscape: A stochastic economic assessment.

The objective of this study was to assess how payments for ecosystem services could assist plantation forestry's integration into pastoral dairy farming in order to improve environmental outcomes and increase business resilience to both price uncertainty and production limits imposed by environmental policies. Stochastic Dominance (SD) criteria and portfolio analysis, accounting for farmers' risk aversion levels, were used to rank different land-use alternatives and landscapes with different levels of plantation forestry integration. The study was focused on a modal 200-ha dairy farm in the Lake Rotorua Catchment of the Central North Island region of New Zealand, where national environmental policies are being implemented to improve water quality and reduce greenhouse gas emissions. Nitrogen and carbon payments would help farmers improve early cash flows for forestry, provide financial leverage to undertake afforestation projects and contribute to improved environmental outcomes for the catchment. The SD criteria demonstrated that although dairy farming generates the highest returns, plantation forestry with nitrogen and carbon payments would be a preferred alternative for landowners with relatively low risk aversion levels who consider return volatility and environmental limits within their land-use change criteria. Using the confidence premium concept, environmental payments to encourage plantation forestry into the landscape were shown to be lower when the majority of landowners are risk averse. The certainty equivalence approach helped to identify the optimal dairy-forestry portfolio arrangements for landowners of different levels of risk aversion, intensities of dairy farming (status quo and intensified) and nitrogen prices. At low nitrogen prices, risk neutral farmers would choose to afforest less than half of the farm and operate at the maximum nitrogen allowance, because dairy farming at both intensities provides the highest return among the different land uses available. However, at relatively low risk aversion levels, farmers would operate at levels below the maximum nitrogen allowance by including plantation forestry to a greater extent, compared to risk neutral farmers, due to its more certain returns. At a high nitrogen price of $400/kg, plantation forestry would completely subsume dairying, across risk aversion and intensity levels. These results confirm that plantation forestry as well as being an environmentally sound land-use alternative, also reduces uncertainty for landowners that are exposed to volatile international markets for dairy commodities.

Direct observation of adsorbed H2-framework interactions in the Prussian Blue analogue MnII3[CoIII(CN)6]2: the relative importance of accessible coordination sites and van der Waals interactions.

Selective recovery of the guest-framework interactions for H(2) adsorbed in a nanoporous Prussian Blue analogue, through differential X-ray and neutron pair distribution function analysis at ca. 77 K, suggests that the H(2) molecule is disordered about a single position at the centre of the pore, ((1/4),(1/4),(1/4)), without binding at accessible Mn(II) sites.

Demand analysis on food: effects of Bolsa Família on dairy consumption as a source of calcium / Análise da demanda de alimentos : efeitos do Bolsa Família sobre o consumo de produtos lácteos como fonte de cálcio / Análisis de la demanda de alimentos : efectos de la Bolsa Família en el consumo de productos lácteos como fuente de calcio

Bolsa Família is a conditional cash transfer program in Brazil, which aims to improve education, health and nutrition in poor households. Dairy products are also representative in terms of food expenses in Brazil besides being an important source of calcium. This paper aims to evaluate effects of Bolsa Família on the dairy products demand. Survey data from 55,700 households collected in 2008/2009 by the Brazilian Bureau of Statistics (IBGE) are used. The Heckman two-step method is applied for the estimation. The results suggested that Bolsa Família increases the probability of buying milk powder and unpasteurized milk. As for policy consideration, managing unpasteurized milk and other nutritional education procedures should be considered to improve health and nutrition for low income families.

Bolsa Família é um programa brasileiro de transferência de renda que visa melhorar a educação, a saúde e a nutrição em famílias de baixa renda. Os produtos lácteos são relevantes na despesa das famílias com alimentação e também uma importante fonte de cálcio. O principal objetivo deste artigo é identificar possíveis efeitos da participação no programa Bolsa Família sobre a demanda de produtos lácteos. Os dados utilizados foram oriundos da Pesquisa de Orçamento Familiar (POF), do Instituto Brasileiro de Geografia e Estatística (IBGE), a qual cobriu 55.700 domicílios em 2008/2009. O método de dois estágios de Heckman foi o utilizado para a elaboração da análise quantitativa. Os resultados sugerem que o Bolsa Família aumenta a probabilidade das famílias em comprar leite em pó e leite não pasteurizado. No âmbito de políticas públicas, uma melhor orientação sobre os riscos de leite não pasteurizado e educação nutricional para as famílias beneficiadas com o programa deveria ser considerada.

Bolsa Família es un programa de transferencia condicional de dinero en Brasil, que tiene como objetivo mejorar la educación, la salud y la nutrición en los hogares pobres. Los productos lácteos son también representativos en términos de gastos de alimentación en Brasil, además de ser una fuente importante de calcio. En este trabajo se estudia el efecto de Bolsa Família en la demanda de productos lácteos. Se utilizan datos de una encuesta a 55.700 hogares recogida en 2008/2009 por la Agencia Brasileña de Estadísticas. Para la estimación se aplica un método Heckman en dos etapas. Los resultados sugieren que Bolsa Família aumenta la probabilidad de compra de leche en polvo y leche sin pasteurizar. En cuanto a la consideración de políticas, la gestión de la leche no pasteurizada y otros procedimientos de educación nutricional deben ser considerados para mejorar la salud y la nutrición de las familias de bajos ingresos.

X-ray and neutron diffraction studies on "Li4.4Sn".

A chemical analysis and detailed structural characterization, using X-ray single crystal and neutron powder diffraction, of the binary lithium-tin compound "Li(4.4)Sn" is presented. Phase analyses and subsequent structural refinements result in the reformulation of "Li(4.4)Sn" as Li(17)Sn(4). The lithium-rich binary phase crystallizes with a complex cubic structure in the space group Ffourmacr;3m, with a = 19.6907(11) A, Z = 20. The improved crystal structure determination indicates well-defined lithium atom positions, some of which differ from those previously reported. The nearly Zintl phase Li(17)Sn(4) exhibits poor metallic behavior similar to that of heavily doped semiconductors. Comparisons of the refined crystal structure with previously reported X-ray crystal structures associated with "Li(4.4)Sn" are discussed.

The development of grain-orientation-dependent residual stressess in a cyclically deformed alloy.

There have been numerous efforts to understand and control the resistance of materials to fracture by repeated or cyclic stresses. The micromechanical behaviours, particularly the distributions of stresses on the scale of grain size during or after mechanical or electrical fatigue, are crucial to a full understanding of the damage mechanisms in these materials. Whether a large microstress develops during cyclic deformation with a small amount of monotonic strain but a large amount of accumulated strain remains an open question. Here, we report a neutron diffraction investigation of the development of intergranular stresses, which vary as a function of grain orientations, in 316 stainless steel during high-cycle fatigue. We found that a large intergranular stress developed before cracks started to appear. With further increase of fatigue cycles, the intergranular stress decreased, while the elastic intragranular stored energy continued to grow. One implication of our findings is that the ratio between the intergranular and intragranular stored energies during various stages of fatigue deformation may validate the damage mechanism and can be used as a fingerprint for monitoring the state of fatigue damage in materials.