flavonoidVernonia amygdalina Del) adalah salah satu tanaman obat yang berasal dari Afrika yang menyebar sampai ke Asia, termasuk Indonesia. Vernonia amygdalina Del dikenal dengan nama lokal tanaman ...Afrika. Tanaman ini secara tradisional telah dimanfaatkan sebagai obat diabetes, demam, hipertensi dan asam urat. Tujuan penelian ini adalah menentukan kadar flavonoid total ekstrak daun, kulit batang dan kayu batang tanaman Afrika. Masing-masing sampel (daun, kulit batang dan batang Afrika) diekstraksi kemudian ditentukan kandungan flavonoid totalnya. Berdasarkan hasil penentuan kadar flavonoid dari ekstrak daun, kulit batang dan batang Afrika diketahui bahwa ekstrak batang memiliki kadar flavonoid total yang paling banyak sebesar 418,15 mg QE/g ekstrak.
Energy poverty in developing regions is a major global concern, with the rural areas of South Asia, South-East Asia and Sub-Saharan Africa being the most affected. The major residential energy ...consumption in these regions is for cooking and lighting, which is basically covered with traditional biomass and fossil fuels. This situation acts as a development barrier, while implying stress on resources and the environment. Solar home systems (SHS) can play an important role in overcoming this problem. Recent technological advances and cost reductions in lithium-ion batteries favour their use in such application. Domestic electric devices with outstanding energy efficiency are becoming the standard around the globe. This paper focuses on exploiting these innovations to provide a solution for domestic energy poverty in developing regions. The layout of a SHS that integrates a lithium-ion battery-pack and is complemented with LED lamps and an energy efficient multicooker is presented. The paper assesses the SHS in contrast with existing practices under domestic energy poverty, with consideration of the learning curve. It is concluded that the cost of energy of the SHS is slightly cheaper than the business as usual case on the short term, and notably cheaper on the longer run. Furthermore, a financing scheme is proposed to overcome implementation barriers. Government support is considered, and quantified based on the SHS carbon abatement and saved fossil fuel subsidies. A substantial share of the initial investment can be covered under such scheme. This case study allows to draw general conclusions on the potential of SHS as a solution for domestic energy poverty in developing regions, on the financing gaps that hamper implementation and eventually on the required actions to overcome these.
•The state of the art of domestic energy poverty in developing regions is summarized.•A solar home system with lithium-ion battery is proposed as a solution.•The solar home system is assessed in contrast with current practices under energy poverty.•The solar home system is more cost effective and has an incremental cost advantage over time.•A financing scheme is suggested to overcome implementation barriers.
•The role of sustainability-oriented standards in global food markets is growing.•We analyze impacts of Fairtrade, Organic, and UTZ standards on coffee farmers in Uganda.•We use survey data and ...propensity score matching with multiple treatments.•Fairtrade increases living standards by 30% and reduces the prevalence and depth of poverty.•For the other two standards, no significant impacts are found.
Voluntary standards are gaining in importance in global markets for high-value foods. We analyze and compare impacts of three sustainability-oriented standards – Fairtrade, Organic, and UTZ – on the livelihoods of smallholder coffee farmers in Uganda. Using survey data and propensity score matching with multiple treatments, we find that Fairtrade certification increases household living standards by 30% and reduces the prevalence and depth of poverty. For the other two certification schemes, no significant impacts are found. Several factors that can explain differential impacts are discussed. Overly general statements about the effects of sustainability standards on smallholder livelihoods may be misleading.
Wetlands are valuable ecosystems providing a variety of important ecosystem services such as food supply and flood control. Due to increasing anthropogenic influences and the impact of climate ...change, wetlands are increasingly threatened and degraded. An effective monitoring of wetlands is therefore necessary to preserve and restore these endangered ecosystems. Earth Observation (EO) data offer a great potential to support cost-effective and large-scale monitoring of wetlands. Current state-of-the-art methods for wetland mapping, however, require large training data and manual effort and can therefore only be locally applied. The focus of this study is to evaluate a methodology for large-scale and highly automated wetland mapping based on current EO data streams. For this purpose, an algorithm for water and wetness detection based on multi-temporal optical imagery and topographic data is presented. Suitable spectral indices sensitive to water and wetness were identified using feature selection methods based on mutual information between optical indices and occurrence of water and wetness. In combination with the Topographic Wetness Index (TWI), these were used to derive monthly water and wetness masks using a dynamic thresholding approach. Aggregating all observations corrected for seasonal bias yielded flooding and wetness frequencies and the Water Wetness Presence (or Probability) Index (WWPI) as an indicator for wetland occurrence or a pre-inventory. To demonstrate the applicability of the proposed method, the algorithm is demonstrated at three study sites with different wetland types in Kenya/Uganda, Algeria, and Austria using Sentinel-2 MultiSpectral Instrument (MSI) imagery. For all sites, the overall accuracy was above 92%. User's and producer's accuracies were higher for water (>96%) than for wetness (>75%). Due to the high degree of automation and low processing time, the proposed method is applicable on a large scale and has already been applied during the production of the Copernicus High Resolution Water-Wetness Layer and within the European Space Agency (ESA) project GlobWetland Africa.
•A highly automated algorithm for water and wetness detection is proposed.•Tile-based image thresholding is applied to spectral and topographic indices.•Water is automatically detected with very high accuracy across different regions.•The Water and Wetness Probability Index provides a basic wetland inventory.
We compiled published and newly-obtained data on the directly-measured atmospheric deposition of total phosphorus (TP), filtered total phosphorus (FTP), and inorganic phosphorus (PO4-P) to open land, ...lakes, and marine coasts. The resulting global data base includes data for c. 250 sites, covering the period 1954 to 2012. Most (82%) of the measurement locations are in Europe and North America, with 44 in Africa, Asia, Oceania, and South-Central America. The deposition rates are log-normally distributed, and for the whole data set the geometric mean deposition rates are 0.027, 0.019 and 0.14 g m(-2) a(-1) for TP, FTP and PO4-P respectively. At smaller scales there is little systematic spatial variation, except for high deposition rates at some sites in Germany, likely due to local agricultural sources. In cases for which PO4-P was determined as well as one of the other forms of P, strong parallels between logarithmic values were found. Based on the directly-measured deposition rates to land, and published estimates of P deposition to the oceans, we estimate a total annual transfer of P to and from the atmosphere of 3.7 Tg. However, much of the phosphorus in larger particles (principally primary biological aerosol particles) is probably redeposited near to its origin, so that long-range transport, important for tropical forests, large areas of peatland and the oceans, mainly involves fine dust from deserts and soils, as described by the simulations of Mahowald et al. (Global Biogeochemical Cycles 22, GB4026, 2008). We suggest that local release to the atmosphere and subsequent deposition bring about a pseudo-diffusive redistribution of P in the landscape, with P-poor ecosystems, for example ombrotrophic peatlands and oligotrophic lakes, gaining at the expense of P-rich ones. Simple calculations suggest that atmospheric transport could bring about significant local redistribution of P among terrestrial ecosystems. Although most atmospherically transported P is natural in origin, local transfers from fertilised farmland to P-poor ecosystems may be significant, and this requires further research.
There has been a growing interest in jatropha- and sugarcane-based biofuels across Sub-Sahara Africa. Biofuel expansion in the region reflects policy concerns related to energy security, poverty ...alleviation and economic development. However, biofuels have also been linked to numerous environmental and socioeconomic impacts such as GHG emissions, water availability/pollution, deforestation, biodiversity loss, poverty alleviation, energy security, loss of access to land and food security to name just a few. Yet there is (a) an insufficient understanding of these impacts (and their synergies) in Sub-Sahara Africa, and (b) a lack of policies that could regulate the biofuel sector and ensure its viability while at the same time preventing its negative impact. The aim of this literature review is to synthesize the current knowledge about biofuel impacts in Africa and to identify priority policy areas that should be targeted for enhancing biofuel sustainability in the continent. The findings of this review indicate that biofuel impacts can be positive or negative depending on several factors such as the feedstock, the environmental/socio-economic context of biofuel production, and the policy instruments in place during biofuel production, use and trade. In most cases there are significant trade-offs but at least part of the negative impacts can be mitigated through careful planning. The incomplete and piecemeal understanding of these trade-offs combined with agronomic, institutional and market failures are currently the most important barriers for the viability and sustainability of biofuel investments in the continent.
Financial institutions play a pivotal role in the efficient allocation of capital resources. However, some households and firms may be excluded from formal financial markets due to asymmetric ...information and market imperfections, thereby adversely affecting equitable income distribution. On the other hand, among other things, access to finance is viewed as one of the key tools to fight poverty. This study develops a novel double FFI Model and applies the structural equation modelling to simultaneously analyze the interaction between financial technology, financial inclusion, and income inequality in a panel of 25 African countries over the periods 2011, 2014, and 2017. The results show that financial inclusion mediates the financial technology-income inequality relationship thus playing a fundamental role in reducing income inequality in Africa. On the policy front, the study urges African policymakers and regulators to craft policies that enhance Fintech developments and financial inclusion.
The spatial distribution and fractional cover of plant functional types (PFTs) is a key uncertainty in land surface models (LSMs) that is closely linked to uncertainties in global carbon, hydrology ...and energy budgets. Land cover is considered to be an Essential Climate Variable because changes in it can result in local, regional or global scale impacts on climate. In LSMs, land cover (LC) class maps are converted to PFT fractional maps using a cross-walking (CW) table by prescribing the fraction of each PFT that occurs within each LC class. In this study we assess the largest plausible range of PFT uncertainty derived from remotely sensed LC maps produced under the European Space Agency Land Cover Climate Change Initiative on simulations of land surface fluxes using 3 leading LSMs. We evaluate the impact of uncertainty due to both LC classification algorithms, and CW procedure, on energy, moisture and carbon fluxes in LSMs. We investigate the maximum plausible range of uncertainty deriving from both LC and CW within the context of a potential biomass scale (bare ground-grass-shrub-tree), representing a gradient from low to high biomass PFTs. More specifically, plausible alternative land cover maps and associated PFT fractional distributions were produced to prioritise low or high biomass vegetation in the LC classification (uncertainty in LC), and subsequently in the assignment of PFT fractions for each LC class (uncertainty in CW), relative to a reference PFT distribution.
We examined the impact of PFT uncertainty on 3 key variables in the carbon, water and energy cycles (gross primary production (GPP), evapo-transpiration (ET), and albedo), for 3 LSMs (JSBACH, JULES and ORCHIDEE) at global scale. Results showed a greater uncertainty in PFT fraction due to CW as opposed to LC uncertainty, for all three variables. CW uncertainty in tree fraction was found to be particularly important in the northern boreal forests for simulated LSM albedo. Uncertainty in the balance between grass and bare soil fraction in arid parts of Africa, central Asia, and central Australia was also found to influence albedo and ET in all models. The spread due to PFT uncertainty for albedo was between 30 and 105% of inter-model uncertainty, for GPP between 20 and 90%, and for ET 0–30%. Each model had a different sensitivity to PFT uncertainty, for example, GPP in JSBACH was found to have a much higher sensitivity to PFT uncertainty in the tropics than JULES and ORCHIDEE, whereas the inverse was true for ET.
These results show that inter-model uncertainty for key variables in LSMs can be reduced by more accurate representation of PFT distributions. Future efforts in land cover mapping should therefore be focused on reducing CW uncertainty through better understanding of the fractional cover of PFTs within a land cover class. Efforts to reduce LC uncertainty should particularly be focused on more accurate mapping of grass and bare soil fractions in arid areas. In the context of Land Surface Models, these results demonstrate that prescribed vegetation distribution in models is a key source of uncertainty that is comparable to the spread between models for key model state variables.
•Plant functional types (PFT) mapped using land cover (LC) and cross-walking (CW).•African & South American savannahs are key to reducing carbon cycle uncertainty.•Uncertainty in bare soil & grass PFTs drives uncertainty in Europe & N America.•Northern high latitude tree cover uncertainty impacts surface albedo.•Clear need to better constrain CW fractions of PFTs using high resolution mapping.
The long-term forecasting of energy supply and demand is of prime importance in Africa due to the steady increase in energy requirements, the non-availability of sufficient resources, the high ...dependence on fossil-fuels to meet these requirements, and the global concerns over the energy-induced environmental issues. This paper is concerned with modelling possible future paths for Africa's energy future and the related emissions. Future energy demand is forecasted based on socio-economic variables such as gross domestic product, income per capita, population, and urbanisation.
The Long-range Energy Alternative Planning System (LEAP) modelling framework is employed to analyse and project energy demand and the related emissions under alternative strategies for the period of 2010–2040. Results of scenarios including business-as-usual (BAU) policies, moderate energy access and accelerate energy access policies, renewable energies promotion and energy efficiency policies and their environmental implications are provided.
The study provides some policy insights and identifies synergies and trade-offs relating to the potential for energy policies to promote universal energy access, enable a transition to renewable energy, and mitigate climate change for a sustainable development.
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•Possible future paths for Africa's energy future and the related emissions are modelled.•Scenarios using an adaptation of Schwartz's scenario approach, under LEAP are developed.•Under the current energy policies, the universal access to modern energy will not be met by 2030.•Policies to accelerate the changes in energy structure are required for sustainable development.•Investing in Energy efficient strategies has emerged as one of the best solution.
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