Mega-trends in the Southern African region

This study aims to describe recent developments in the Southern African region by documenting a set of mega-trends defining social, economic, political and environmental conditions. It includes analysis of the recent past as well as projections of future trends. To the extent possible, the report is based on information from 2010 to the present, except in some cases where more recent information was not available. The purpose of this analysis is to get a snapshot of current conditions in the Southern African region and the dynamics that generated them, to inform the design and implementation of investments to secure climate-resilient agricultural livelihoods in the region. The study goes beyond simply tracing trends, however, and provides guidance on how the information can best be used in making plans for the future. The mega-trend analysis gives insights into forces that will shape the future but does not provide predictions of the future. Humans are typically very linear thinkers and tend to look at trends from the past and project them forwards into the future, and we often fall into the trap of thinking that the future is defined by what has happened in the past. There is considerable uncertainty over how several of these mega-trends will play out in the near future, with the possibility of major disruptions and changes on the horizon. This can be seen quite clearly in the impact of the COVID-19 pandemic which is still unfolding, and which is already disrupting expectations of future conditions. This uncertainty of future conditions greatly complicates decision-making today. To address this complication, the development of scenarios to identify a range of plausible futures is an important tool for decision-makers. In the final section of the report we give examples of recent scenario work in the region to illustrate how the analysis of megatrends and their uncertainties can be useful in strategic decision-making under uncertainty

What Is the Evidence Base for Climate-Smart Agriculture in East and Southern Africa? A Systematic Map

More than 500 million USD will soon be invested in climate-smart agriculture (CSA) programmes in sub-Saharan Africa. Improving smallholder farm management is the core of most of these programmes. However, there has been no comprehensive information available to evaluate how changing agricultural practices increases food production, improves resilience of farming systems and livelihoods, and mitigates climate change—the goals of CSA. Here, we present a systematic map—an overview of the availability of scientific evidence—for CSA in five African countries: Tanzania, Malawi, Mozambique, Zimbabwe and Zambia. We conducted a systematic literature search of the effects of 102 technologies, including farm management practices (e.g., leguminous intercropped agroforestry, increased protein content of livestock diets, etc.), on 57 indicators consistent with CSA goals (e.g., yield, water use efficiency, carbon sequestration, etc.) as part of an effort called the "CSA Compendium". Our search of peer-reviewed articles in Web of Science and Scopus produced 150,567 candidate papers across developing countries in the global tropics. We screened titles, abstracts and full texts against predetermined inclusion criteria, for example that the investigation took place in a tropical developing country and contains primary data on how both a CSA practice and non-CSA control affect a preselected indicator. More than 1500 papers met these criteria from Africa, of which, 153 contained data collected in one of the five countries. Mapping the studies shows geographic and topical clustering in a few locations, around relatively few measures of CSA and for a limited number of commodities, indicating potential for skewed results and highlighting gaps in the evidence. This study sets the baseline for the availability of evidence to support CSA programming in the five countries

A Queueing Theoretic Approach to Decoupling Inventory

This paper investigates the performance of different hybrid push-pull systems with a decoupling inventory at the semi-finished products and reordering thresholds. Raw materials are ‘pushed’ into the semi-finished product inventory and customers ‘pull’ products by placing orders. Furthermore, production of semi-finished products starts when the inventory goes below a certain level, referred to as the threshold value and stops when the inventory attains stock capacity. As performance of the decoupling stock is critical to the overall cost and performance of manufacturing systems, this paper introduces a Markovian model for hybrid push-pull systems. In particular, we focus on a queueing model with two buffers, thereby accounting for both the decoupling stock as well as for possible backlog of orders. By means of numerical examples, we assess the impact of different reordering policies, irregular order arrivals, the set-up time distribution and the order processing time distribution on the performance of hybrid push-pull systems

Towards Understanding the Origin of Cosmic-Ray Electrons

Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 1.4 TeV based on 28.1 x 10(6) electrons collected by the Alpha Magnetic Spectrometer on the International Space Station. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. The electron flux exhibits a significant excess starting from 42.1(-5.2)(+5.4) GeV compared to the lower energy trends, but the nature of this excess is different from the positron flux excess above 25.2 +/- 1.8 GeV. Contrary to the positron flux, which has an exponential energy cutoff of 810(-180)(+310) GeV, at the 5 sigma level the electron flux does not have an energy cutoff below 1.9 TeV. In the entire energy range the electron flux is well described by the sum of two power law components. The different behavior of the cosmic-ray electrons and positrons measured by the Alpha Magnetic Spectrometer is clear evidence that most high energy electrons originate from different sources than high energy positrons