14 research outputs found
Effect of Maternal HIV and Malaria Infection on Pregnancy and Perinatal Outcome in Zimbabwe
No full textTo investigate the effect of isolated or concomitant infection with malaria and HIV on pregnancy and neonatal outcome
Long-term annual climate trends around the Breton Plots area, Alberta: is there any evidence of local climate change?
No full textThe objective of this research was to investigate the long-term trends in historical climate variables using the data collected near the classical Breton Plots (Alberta, Canada) and to determine if the data show any evidence of local climate change. The climate data used for the study were obtained from the Alberta Climate Information Service (ACIS) for the years 1901 to 2020. Various parametric statistical analyses were conducted to determine if monotonic trends occurred in the climate variables over time, and the analyses were conducted on the annual data as well as the 30-year climate normals. Large fluctuations in annual climate variables occurred, but a positive linear trend was observed in the average annual and growing season minimum air temperatures over time. Between 1901 and 2020 the annual minimum air temperature average increased at a rate of 0.3The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Historic climate change trends and impacts on crop yields in key agricultural areas of the prairie provinces in Canada: a literature review
No full textThe objective of this literature review was to compile research findings on climate change and its impacts on crop production in Prairie Provinces of Canada. Our search strategy included finding primary literature articles from various databases. Seven articles reported increases in average and minimum air temperature over time in the Prairie Provinces of Canada. Increases in maximum air temperature were smaller than that for minimum air temperature. Growing degree days (GDD) and corn heat units (CHU) also increased over time, which has allowed for potential expansion of corn growth northwards. While overall increases in average annual precipitation and growing season precipitation have occurred in Canada between1900 and 2021, western Canada showed increases in some regions but decreases in others. Off-season precipitation and snow cover duration in Canada have decreased since 1950. The number of frost-free days has increased across Canada, on the Prairies and southern Saskatchewan since 1900. Annual snowfall has decreased since 1950 and across Canada the annual maximum snow depth has also decreased. Overall, studies focusing on the Prairie Provinces in Canada have shown accelerated changes in several climate parameters over time, affecting cropping areas and crop yields.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Management impacts on organic carbon under continuous perennial grass, perennial grass-legume mixture, and annual cereals on a thick Black Chernozemic soil
No full textImpacts of annual and perennial pasture management on soil organic carbon (SOC) and equivalent SOC stocks (equal soil mass basis) were investigated in two trials [(CAESA (1994 to 1997) and BMP (2008 to 2012) trials] conducted on the same experimental paddocks at Lacombe, Alberta. The original site was broken from perennial grass in 1992 and the CAESA trial established in 1993. Between 1994 and 1997, half of the paddocks included winter triticale and a mixture of triticale and spring barley; half included smooth and meadow bromegrass; and each paddock was light, medium, or heavily grazed. The BMP trial (2008 to 2012) on the same paddocks included fertilized, direct seeded barley as silage; grazing and haying of unfertilized meadow bromegrass, fertilized meadow bromegrass, and meadow bromegrass and alfalfa mixture; and unfertilized oldgrass that was continuous since 1994. Between trials (1998 to 2007) all paddocks received no fertilizer. In the 0-15 cm depth SOC under oldgrass was constant between 1994 and 2012 and averaged 88 Mg C haThe presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Continuous multi-criteria methods for crop and soil conservation planning on La Colacha (Río Cuarto, Province of Cordoba, Argentina)
No full textAgro-areas of Arroyos Menores (La Colacha) west and south of Rand south of R?o Cuarto (Prov. of Cordoba, Argentina) basins are very fertile but have high soil loses. Extreme rain events, inundations and other severe erosions forming gullies demand urgently actions in this area to avoid soil degradation and erosion supporting good levels of agro production. The authors first improved hydrologic data on La Colacha, evaluated the systems of soil uses and actions that could be recommended considering the relevant aspects of the study area and applied decision support systems (DSS) with mathematic tools for planning of defences and uses of soils in these areas. These were conducted here using multi-criteria models, in multi-criteria decision making (MCDM); first of discrete MCDM to chose among global types of use of soils, and then of continuous MCDM to evaluate and optimize combined actions, including repartition of soil use and the necessary levels of works for soil conservation and for hydraulic management to conserve against erosion these basins. Relatively global solutions for La Colacha area have been defined and were optimised by Linear Programming in Goal Programming forms that are presented as Weighted or Lexicographic Goal Programming and as Compromise Programming. The decision methods used are described, indicating algorithms used, and examples for some representative scenarios on La Colacha area are given
Agroecological and other innovative approaches for sustainable agriculture and food systems that enhance food security and nutrition. A report by the High Level Panel of Experts on Food Security and Nutrition of the Committee on World Food Security
No full textFood systems and agriculture are at a crossroads and a profound transformation is needed at all scales, not only to achieve Sustainable Development Goal 2 (SDG2) to “end hunger and all forms of malnutrition” by 2030 but also to address Agenda 2030 in its entirety, including human and environmental health, climate change, equity and social stability. Current trends, such as the new increase, since 2014, in the number of undernourished people and the alarming rate of all forms of malnutrition in all countries, and related tensions will be exacerbated if we fail to design and implement, in a very near future, food systems that ensure food security and nutrition while addressing all sustainability challenges. Agroecological and other innovative approaches in agriculture are increasingly praised for their potential contribution to reach these crucial goals. This report adopts a dynamic perspective, centred on the key concepts of transition and transformation. Ultimately, this rich and comprehensive report aims to fuel an exciting policy convergence process and help remove the lock-ins by developing a common understanding of these matters, so that concrete transition pathways can be implemented at all relevant scales, from farm, community and landscape to national, regional and global levels
Multi-stakeholder partnerships to finance and improve food security and nutrition in the framework of the 2030 Agenda. A report by the High Level Panel of Experts on Food Security and Nutrition of the Committee on World Food Security
No full textThe 2030 Agenda for Sustainable Development and the Addis Ababa Action Agenda encouraged the use of multistakeholder partnerships (MSPs) to complement the efforts of national governments and intergovernmental organizations in ending hunger and poverty and achieving sustainable development. In this context, MSPs are gaining traction, as a part of a new approach to governance, and as a topic for science. Yet, evidence and data are still limited and quickly evolving. This report highlights transparency and accountability as key conditions: to align MSPs' work with the progressive realization of the right to adequate food; to better use existing resources for FSN and sustainable development; and even to potentially attract new resources. This report also suggests a set of criteria to enable governments and non-state actors to perform their own assessments of MSPs following a common methodology, as well as pathways to improve their contribution to financing and improving FSN
Effect of cutting management and nitrogen supply on yield and quality of Napier grass (Pennisetum purpureum)
No full textIn a series of cutting experiments, average apparent nitrogen recovery of applied fertilizer N by Napier grass was approximately 50%. Incorporation of cattle manure improved nitrogen utilization. Mixtures with Desmodium intortum substantially improved yield and protein content. There was a fair to good relation between morphology and crude protein content and in vitro organic matter digestibility of Napier grass
An impact assessment of the SADC FTA on bilateral trade relations between South Africa and Zimbabwe
No full textThe Journal paper uses the Gravity Model of International Trade to investigate the impact of the Southern African Development Comuunity (SADC) Free Trade Area (FTA) on trade between South Africa and Zimbabwe. The study found out that South Africa gained more in trade by 88.4% if the country used the SADC FTA than the 1964 Bilateral Trade Agreement which was between South Africa and Zimbabwe. In addition, there was trade diversion of 176% for Zimbabwe when trading in SADC FTA. Furthermore the paper showed that South Africa will in future trade more with countries such as the Seychelles and Angola whilst Zimbabwe will gain more in trade if it trades with South Africa. The paper recommends that there is need for Zimbabwe and South Africa to expand trade with SADC Countries in order to promote intra-regional trade.TFij - This is the dependent variable which shows annual trade of exports plus imports of SADC member states. Other studies which have used the gravity model as their methodology such as Sunge & Mapfumo (2014) and Simwaka (2011) have used the log of exports as the dependent variable arguing that imports in Africa are understated in order to minimize their import bills. However this may not be holistic view in all countries and will not reflect the true picture of trading activities in Africa.
Yj and Yi - These are explanatory quantitative variables which show the economic sizes of the exporting and importing countries. Ogunkola (1998) explains that the higher the GDP for exporting and importing countries, the higher is the respective countries' potential for foreign product demand
Distij- This is a quantitative explanatory variable which is a proxy to transportation costs in bilateral trade. Simwaka (2001) uses the quality of infrastructure as a proxy for transport costs as the author highlights that distance may be biased if the poor and not well connected. However distance is a traditional variable which is calculated in kilometers from the capital city of one SADC member state to the other capital city of a SADC member state
contig- This is a dummy explanatory variable which represents the common borders between SADC member states. The variable will show one if there is a common border between an importing country and the exporting country and zero if there is no common border between the two. Countries with common borders will trade more than countries without common borders.
lang- This is a qualitative variable which takes the value of one if the importing country has a common language with the exporting country and zero otherwise.
TC- The variables show trade creation in the SADC region. The dummy variables takes the value of one if both the importing and exporting countries are in the SADC Free Trade Area and zero otherwise
TD- The variable shows trade diversion in SADC trade. The dummy variable represents one if one of the member states is in the SADC FTA and zero otherwise.
llc- This is a dummy variable which represents one if the exporting country is landlocked and zero otherwise
excij - Bergstand (1985) explains that the exchange rate variable is important to show trade variation between member states. The quantitative variable will determine annual exchange rate by the importing country's currency unit per one unit of the exporting country's currency. Following Binh et al (2013) the variable is calculated as the annual average of the importing country's currency unit per US dollar divided by the annual average of the exporting country's national currency unit per US dollar per year.
PIi & PEj- These two quantitative variables estimate the market size of member states. A member state with a larger market size than the other is more likely to trade more in the region.
This is a panel data set consisting of 16 SADC countries. and data was obtained from World Bank's World Development Indicators, CEPII and own computations in terms of dummy variables .Data was collected from various websites such as the World Bank World Development Indicators , CEPII and own computations of dummy variables. The data was colllected and arranged in excel documents and stata files
Soil macrofauna functional groups and their effects on soil structure, as related to agricultural management practices across agroecological zones of Sub-Saharan Africa
No full textThis study aimed at understanding the effects of crop management practices on soil macrofauna and the links with soil aggregation and soil organic matter dynamics, which is key to the improvement of infertile or degrading soils in Sub-Sahara Africa. Soil macrofauna, especially earthworms and termites, are important components of the soil ecosystem and, as ecosystem engineers, they influence the formation and maintenance of soil structure and regulate soil processes, such as organic matter decomposition and nutrient dynamics. In comparison with natural systems, earthworm and termite diversity and abundance were low in fallow, high soil-carbon (C) and low soil-C arable treatments in 12 long-term trial fields across the sub-humid to semi-arid tropical zones in Eastern and Western Africa. Continuous crop production had significant negative effects on earthworm diversity, but little effect on termite diversity, as compared to long-term fallow. Agricultural management resulting in high soil C increased earthworm and termite diversity as compared to low-C soil.Long-term application of manure in combination with fertilizer resulted in higher earthworm diversity and biomass, associated with improved soil aggregation and enhanced C and N stabilization within this more stable soil structure. These practices therefore result in the dual benefits of improving soil physical and chemical properties. A micromorphological study of undisturbed soil thin sections showed that fallowing, conservation tillage plus residue application (in East Africa) and hand-hoeing plus manure (in West Africa) enhanced biogenic soil structure formation, resulting in a well developed soil structure and a continuous pore system characterized by many faunal channels. In contrast,intensive tillage and absence of organic inputs resulted in soil with less biogenic soil structural features. Farmers in Nyabeda, West-Kenya, were aware of the activities and nesting habits of termites, but 90% percent of the farmers perceived termites as pests.This study has shown that the soil macrofauna, especially earthworms, and, to a lesser extent termites, are important drivers of stable soil aggregation in Sub-Saharan agroecosystems, with beneficial effects on soil physical and chemical properties. However, their beneficial impact on soil aggregation is reduced with increasing management intensity and associated soil disturbance due to cultivation. This knowledge is important in designing agricultural management systems aimed at increasing long-term soil fertility in Sub-Saharan Africa
