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Biofuel-Food Market Interactions: A Review of Modeling Approaches and Findings
Gbadebo Oladosu,Siwa Msangi
Agriculture , 2013, DOI: 10.3390/agriculture3010053
Abstract: The interaction between biofuels and food markets remains a policy issue for a number of reasons. There is a continuing need to understand the role of biofuels in the recent spikes in global food prices. Also, there is an ongoing discussion of changes to biofuel policy as a means to cope with severe weather-induced crop losses. Lastly, there are potential interactions between food markets and advanced biofuels, although most of the latter are expected to be produced from non-food feedstocks. This study reviews the existing literature on the food market impacts of biofuels. Findings suggest that initial conclusions attributing most of the spike in global food prices between 2005 and 2008 to biofuels have been revised. Instead, a multitude of factors, in addition to biofuels, converged during the period. Quantitative estimates of the impacts of biofuels on food markets vary significantly due to differences in modeling approaches, geographical scope, and assumptions about a number of crucial factors. In addition, many studies do not adequately account for the effects of macroeconomic changes, adverse weather conditions and direct market interventions during the recent food price spikes when evaluating the role of biofuels.
Biofuels and the Future of Food: Competition and Complementarities
Simla Tokgoz,Wei Zhang,Siwa Msangi,Prapti Bhandary
Agriculture , 2012, DOI: 10.3390/agriculture2040414
Abstract: In this paper, we draw the key linkages between future biofuels growth on agricultural commodity prices, and highlight some of the key uncertainties over OECD fuel and energy policies, and their implications for global agricultural markets and the world food situation. Our results show some of the implications that biofuels expansion has on crop area expansion in regions where environmental concerns exist over land use change and the possible impacts on the environment. We also point to some promising areas for future research and specify some implications for policy interventions.
Agriculture and food security in Asia: the role of agricultural research and knowledge in a changing environment
Mark Rosegrant,Claudia Ringler,Siwa Msangi Tingju Zhu,Timothy Sulser
Journal of SAT Agricultural Research , 2007,
Abstract: Asia has made significant progress in increasing its agricultural productivity and reducing poverty since the 1960s. Yet real world food prices of most cereals and meats are now projected to rise, reversing a long-established downward trend with adverse impacts on poor consumers in Asia and elsewhere. Growing resource scarcity, particularly of water, will increasingly constrain food production growth, and climatic stresses will likely shrink Asian farmers’ abilities to produce grains, as is predicted for the Indo-Gangetic plains. Meanwhile, growing demand for high-value foods, such as livestock, fish, vegetables, and fruits will put further pressure on the natural resource base. Moreover, bioenergy demands will compete with the land and water resources that are used for food. The consequences of these pressures will adversely affect food security and goals for human well-being, slowing progress in reducing childhood malnutrition. Drawing on projections of the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT), we find that changes in investments in agricultural research and knowledge (ARK) are required to boost crop yields and growth in livestock numbers. If aggressive investments in ARK are combined with advances in other, complementary sectors, such as access to water and secondary education, then positive impacts could be further strengthened.
Urban Climate Analysis with Remote Sensing and Climate Observations: A Case of Morogoro Municipality in Tanzania  [PDF]
Siwa Ernest, Augustino R. Nduganda, Japhet J. Kashaigili
Advances in Remote Sensing (ARS) , 2017, DOI: 10.4236/ars.2017.62009
Abstract: Rapid urbanization is threatening sustainable development of urban areas in Tanzania. Among the risks of rapid urbanization are Urban Heat Island (UHI) effect and climate change. While this has been noted, it is not known to what extent these risks are being realized in fast growing urban areas like Morogoro and other areas of similar geographic and climatic conditions. Therefore a study was conducted to assess the influence of urbanization on UHI and climate in Morogoro Municipality using remote sensing and climate data. Landsat imageries acquired in 1990, 2000 and 2015 were used to assess the change of impervious surface for the year 1990 to 2015 using a Classification and Regression Tree (CART). Radiant surface temperature and normalized difference vegetation index (NDVI) were derived from thermal band and reflectance bands respectively. Mann-Kendall test was used to analyze climate data for trends. Results revealed an increase of impervious surface (built up areas) from 9 km2 in 1990 to 48 km2 in 2000 and 82 km2 in 2015; which is associated with UHI. UHI was not apparent in 1990, but was apparent in 2000 and 2015 with the temperature rise of 1.08°C and 1.22°C respectively. A linear relationship between radiant surface temperature (TB ) and percent Impervious Surface (ISA); and between TB and NDVI it revealed that NDVI is better indicator of variations in TB dynamics than percent ISA. Mann-Kendall test indicated a significant increasing trend in mean annual maximum temperature. The results imply that increasing ISA coupled with vegetation degradation has contributed to temperature rise and change. Consequently, Morogoro Municipality residents are likely to suffer heat stress due to rapid urbanization. It is recommended that education on the use of reflective surfaces should be given to the residents; and an effective master plan that protects vegetation should be in place.
Field and Laboratory Evaluation of Bioefficacy of an Insect Growth Regulator (Dimilin) as a Larvicide against Mosquito and Housefly Larvae
Shandala Msangi,Ester Lyatuu,Eliningaya J. Kweka
Journal of Tropical Medicine , 2011, DOI: 10.1155/2011/394541
Abstract: The inhibitory function of Dimilin (Diflubenzuron), mostly a chitin synthesis regulator, on the ecdysis of mosquitoes (Anopheles gambiae s.l., Culex quinquefasciatus) and housefly was evaluated in the field and in laboratory. Three formulations of Diflubenzuron were evaluated in this study: Dimilin, Wettable powder (25%), Dimilin granules (2%), and Dimilin tablets (2%). The laboratory and field evaluation used different rates of concentrations of these formulations. Generally, at higher dosages larvae developments, eggs hatchability and pupation were impossible. The development of mosquitoes was significantly higher in control while highly depressed in different dosages of treatment in both laboratory and field experiments. In houseflies, the adult population decreased sharply after treatment of their breeding sites while pupae mortality was noticed to be high in laboratory-treated samples. Dimilin could be opted as one of the choice of the larval control chemicals to be incorporated in the integrated vector control programmes in urban and rural areas. 1. Introduction The mosquito Anopheles gambiae s.l., and Culex quinquefasciatus (Diptera: Culicidae) are the principal vector of malaria and filariasis in several tropical regions, respectively. Pesticide treatment has continued to be employed as the principal measure for their control [1]. However, resistance of mosquitoes to organochlorides, organophosphate, and pyrethroid pesticides have been reported in various studies [2–7]. These pesticides are frequently used for their control as well as in agriculture. The control of mosquitoes can best be achieved through integrated vector management [8, 9]. Although control of the adult mosquitoes by using insecticides, either in indoor residual spraying or by insecticide-treated materials, are currently the most widely used strategy [10–12], the control of larvae at their breeding sites is another suitable option [9, 13]. The strategy may reduce population of adult mosquitoes by proper and selective larviciding in the breeding habitats of mosquitoes. Larviciding involve the use of both chemical insecticides and the insect growth regulators (IGR) in controlling larvae of various insect pests [14–16]. The IGRs, unlike the chemical larvicides, are strictly arthropod-specific and environmental safe [17]. In public health, the larvicides are usually indicated for vectors or pests which tend to breed in permanent or semipermanent water bodies or places that can be identified and treated [18]. Therefore, larviciding programs can be complementary to control measures
Protective efficacy of menthol propylene glycol carbonate compared to N, N-diethyl-methylbenzamide against mosquito bites in Northern Tanzania
Kweka Eliningaya J,Munga Stephen,Mahande Aneth M,Msangi Shandala
Parasites & Vectors , 2012, DOI: 10.1186/1756-3305-5-189
Abstract: Background The reduction of malaria parasite transmission by preventing human-vector contact is critical in lowering disease transmission and its outcomes. This underscores the need for effective and long lasting arthropod/insect repellents. Despite the reduction in malaria transmission and outcomes in Tanzania, personal protection against mosquito bites is still not well investigated. This study sought to determine the efficacy of menthol propylene glycol carbonate (MR08), Ocimum suave as compared to the gold standard repellent N, N-diethyl-methylbenzamide (DEET), either as a single dose or in combination (blend), both in the laboratory and in the field against Anopheles gambiae s.l and Culex quinquefasciatus. Methods In the laboratory evaluations, repellents were applied on one arm while the other arm of the same individual was treated with a base cream. Each arm was separately exposed in cages with unfed female mosquitoes. Repellents were evaluated either as a single dose or as a blend. Efficacy of each repellent was determined by the number of mosquitoes that landed and fed on treated arms as compared to the control or among them. In the field, evaluations were performed by human landing catches at hourly intervals from 18:00 hr to 01:00 hr. Results A total of 2,442 mosquitoes were collected during field evaluations, of which 2,376 (97.30%) were An. gambiae s.l while 66 (2.70%) were Cx. quinquefaciatus. MR08 and DEET had comparatively similar protective efficacy ranging from 92% to 100 for both single compound and blends. These findings indicate that MR08 has a similar protective efficacy as DEET for personal protection outside bed nets when used singly and in blends. Because of the personal protection provided by MR08, DEET and blends as topical applicants in laboratory and field situations, these findings suggest that, these repellents could be used efficiently in the community to complement existing tools. Overall, Cx. quinquefasciatus were significantly prevented from blood feeding compared to An. gambiae s.l. Conclusion The incorporation of these topical repellents for protection against insect bites can be of additional value in the absence or presence of IRS and ITNs coverage. However, a combination of both the physical (bed nets) and the repellent should be used in an integrated manner for maximum protection, especially before going to bed. Additional research is needed to develop repellents with longer duration of protection.
Field evaluation of the bio-efficacy of three pyrethroid based coils against wild populations of anthropophilic mosquitoes in Northern Tanzania
Msangi Shandala,Mwang′onde Beda,Mahande Aneth,Kweka Eliningaya
Journal of Global Infectious Diseases , 2010,
Abstract: Aims: This study aims to assess the feeding inhibition and repellency effect of three brands of mosquito coils in experimental huts (East African design). Evaluated products were all pyrethroid-based mosquito coils - Kiboko , Total and Risasi . Mosfly (0.1% D-allethrin) was a positive control. Indoor resting behavior, feeding inhibition and induced exophily were measured as responses of burnt coil smoke in huts. Materials and methods: Resting mosquitoes were collected inside the huts, in window traps and verandah traps using mechanical aspirators. Identified to species level and sex. Results: A total of 1460 mosquitoes were collected, 58.9% (n=860) were Anopheles gambiae s.l while 41.1% (n=600) Culex quinquefasciatus. Indoor resting mosquitoes in all treated huts were significantly reduced than in negative control (DF=4, F=18.6, P < 0.001). Species found to rest indoors were not statistical different between the positive control (Mosfly coil) and other three treated huts (DF=3, F=1.068, P=0.408). Cx.quinquefasciatus had significantly higher induced exophily in all treatments comparing to An.gambiae s.l (DF=1, F=5.34, P=0.050). Comparison between species (An.gambiae s.l and Cx. quinquefasciatus) for the feeding inhibition among treated huts was not statistically significant (DF=1, F=0.062, P=0.810). Conclusion: Introduction of several personal protection measures will be ideal to supplement the existing gap in reducing the man vector contacts hence lowering the disease transmission.
Implications of Land Use Land Cover Change and Climate Variability on Future Prospects of Beef Cattle Production in the Lake Victoria Basin  [PDF]
Japhet Joel Kashaigili, Emmanuel Zziwa, Siwa Ernest, Emma Laswai, Bernard Musana Segatagara, Denis Mpairwe, Reuben Mpuya Joseph Kadigi, Cyprian Ebong, Samuel Katambi Mugasi, Germana Henry Laswai, Mutimura Mupenzi, Polycarp Jacob Ngowi, Ibrahim Lwaho Kadigi
American Journal of Climate Change (AJCC) , 2015, DOI: 10.4236/ajcc.2015.45037
Abstract: This paper presents the lessons learnt from a research project titled “Improving Beef Cattle Productivity for Enhanced Food Security and Efficient Utilization of Natural Resources in the Lake Victoria Basin” which includes Tanzania, Uganda and Rwanda. The key focus is on the implications of land use land cover change and climate variability on the future prospects of beef cattle production in this region. The study utilizes information and data from natural resources and climate components to deduce the impact of land use and land cover changes on climate variability. Additional analysis is conducted to summarize the land use and land cover data to carry out analysis on climate data using the Mann-Kendal test, linear regression and moving averages to reveal patterns of change and trends in annual and seasonal rainfall and temperature. The findings reveal that the study areas of Rwanda, Uganda and Tanzania in the Lake Victoria Basin (LVB) have changed over time following land cover manipulations and land use change, coupled with climate variability. The grazing land has been converted to agriculture and settlements, thereby reducing cattle grazing land which is the cheapest and major feed source for ruminant livestock production. Although the cattle population has been on the increase in the same period, it has been largely attributed to the fact that the carrying capacity of available grazing areas had not been attained. The current stocking rates in the LVB reveal that the rangelands are greatly overstocked and overgrazed with land degradation already evidenced in some areas. Climate variability coupled with a decrease in grazing resources is driving unprecedented forage scarcity which is now a major limiting factor to cattle production. Crop cultivation and settlement expansion are major land use types overtaking grazing lands; therefore the incorporation of crop residues into ruminant feeding systems could be a feasible way to curtail rangeland degradation and increase beef cattle production.
The evolution of haematological and biochemical indices in HIV patients during a six-month treatment period
J Mgogwe, H Semvua, R Msangi, C Mataro, D Kajeguka, J Chilongola
African Health Sciences , 2012,
Abstract: Objective: To assess haematological and biochemical parameters in Human Immunodeficiency Virus (HIV) patients under going antiretroviral therapy. Methods: We enrolled HIV patients from, 18-65 years, who were under first line antiretroviral therapy and followed them for six months from February 2010 for changes in haematological and biochemical parameters. Profiles for ALAT, creatinine, amylase, cholesterol, CD4+ and total lymphocytes, haemoglobin, and monocytes were studied every three months. Results: There was an increase of both, CD4+ lymphocyte counts from 233.57 cells/mm3 to 336.45 cells/mm3 and total lymphocytes from 45 to 46.6 103 cells /μl, after six months. The haemoglobin level dropped from 8.8 g/L to 7.52 g/L. We observed an increase in ALAT from 40.27 to 47.42 U/L, amylase from 178.9 to 193.97 U/L, and cholesterol from 5.88 to 8.40 mmol/L. Creatinine levels decreased from 117.4 to 115.0 μmol/L. Conclusion: The use of ARVs boosts CD4+ and total lymphocyte counts. Prolonged use of antiretroviral drugs (ARVs) is associated with variable degrees of liver and pancreatic damage, hypercholesteremia, and anaemia in some patients. Since many of these side effects are multi-factorial, management of HIV patients should take into consideration such side effects in making treatment decisions based on periodic evaluation of these parameters.
A resting box for outdoor sampling of adult Anopheles arabiensis in rice irrigation schemes of lower Moshi, northern Tanzania
Eliningaya J Kweka, Beda J Mwang'onde, Epiphania Kimaro, Shandala Msangi, Charles P Massenga, Aneth M Mahande
Malaria Journal , 2009, DOI: 10.1186/1475-2875-8-82
Abstract: Three resting boxes were evaluated against human landing catch. Two were baited with cow odour, while the third was unbaited. The inner parts of the boxes were covered with black cloth materials. Experiments were arranged in latin-square design. Boxes were set in the evening and left undisturbed; mosquitoes were collected at 06:00 am the next morning, while human landing catch was done overnight.A total of 9,558 An. arabiensis mosquitoes were collected. 17.5% (N = 1668) were collected in resting box baited with cow body odour, 42.5% (N = 4060) in resting box baited with cow urine, 15.1% (N = 1444) in unbaited resting box and 24.9% (N = 2386) were collected by human landing catch technique. In analysis, the house positions had no effect on the density of mosquitoes caught (DF = 3, F = 0.753, P = 0.387); the sampling technique had significant impact on the caught mosquitoes densities (DF = 3, F 37. 944, P < 0.001).Odour-baited resting boxes have shown the possibility of replacing the existing traditional method (human landing catch) for sampling malaria vectors in areas with a high proportion of An. arabiensis as malaria vectors. Further evaluations of fermented urine and longevity of the urine odour still need to be investigated.Several trapping techniques have been deployed in sampling malaria vectors population in the world [1-3]. Human landing catch has been considered as the gold standard method in mosquito sampling for surveillances and control programmes to estimate the infectivity rates, species abundance and mosquitoes dynamics [4]. With the increase of ethical issues in using humans as subject in collection of disease vectors, alternative simple methods, such as odour-baited traps, need to be developed and evaluated for their effectiveness [5]. Host odours provide olfactory cues by which haematophagous insects locate host for their blood meal [6]. Mosquitoes are the most important disease vectors in sub-Saharan Africa [7]. Odour-baited traps have shown to be
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