Recalculating GHG emissions saving of palm oil biodiesel

In 2010, the Renewable Energy Directive (RED) came into force in the EU and establishes a framework for achieving legally binding greenhouse gas (GHG) emission reductions. Only sustainable biofuels can be counted towards Member State targets. The aim of this paper is to calculate realistic and transparent scenario-based CO₂-emission values for the GHG emissions savings of palm oil fuel compared with fossil fuel. Using the calculation scheme proposed by the RED, we derive a more realistic overall GHG emissions saving value for palm oil diesel by using current input and output data of biofuel production (e.g. in South-East Asia). We calculate different scenarios in which reliable data on the production conditions (and the regarding emission values during the production chain) of palm oil diesel are used. Our results indicate values for the GHG emissions savings potential of palm oil biodiesel not only above the 19 % default and 36 % typical value published in RED but also above the 35 % sustainable threshold. Our findings conclude the more accurate GHG emissions saving value for palm oil feedstock for electricity generation to be 52 %, and for transportation biodiesel between 38.5 and 41 %, depending on the fossil fuel comparator. Our results confirm the findings by other studies and challenge the official typical and default values published in RED. As a result, the reliability of the Directive to support the EU’s low-carbon ambitions is being undermined, exposing the EU and commission to charges of trade discrimination and limiting the ability of Member States to achieve their legally binding GHG emission reductions.     

The water footprint of sweeteners and bio-ethanol

An increasing demand for food together with a growing demand for energy crops result in an increasing demand for and competition over water. Sugar cane, sugar beet and maize are not only essential food crops, but also important feedstock for bio-ethanol. Crop growth requires water, a scarce resource. This study aims to assess the green, blue and grey water footprint (WF) of sweeteners and bio-ethanol from sugar cane, sugar beet and maize in the main producing countries. The WFs of sweeteners and bio-ethanol are mainly determined by the crop type that is used as a source and by agricultural practise and agro-climatic conditions; process water footprints are relatively small. The weighted global average WF of sugar cane is 209 m³/tonne; for sugar beet this is 133 m³/tonne and for maize 1222 m³/tonne. Large regional differences in WFs indicate that WFs of crops for sweeteners and bio-ethanol can be improved. It is more favourable to use maize as a feedstock for sweeteners or bio-ethanol than sugar beet or sugar cane. The WF of sugar cane contributes to water stress in the Indus and Ganges basins. In the Ukraine, the large grey WF of sugar beet contributes to water pollution. In some western European countries, blue WFs of sugar beet and maize need a large amount of available blue water for agriculture. The allocation of the limited global water resources to bio-energy on a large scale will be at the cost of water allocation to food and nature.     

The use of biomass production and allometric models to estimate carbon sequestration of <Emphasis Type="Italic">Jatropha curcas</Emphasis> L. plantations in western Burkina Faso

The topic of carbon sequestration in plants has received much attention recently due to concerns about global climate change, which is being exacerbated by deforestation. In the early days of the global bioenergy boom, the private sector and non-government organizations enthusiastically promoted the planting of Jatropha curcas L. as a key candidate shrub species for the production of bioenergy in West Africa. This study investigates the aboveground biomass production and carbon sequestration potential of J. curcas, which is already widely cultivated for the production of oil seeds, biodiesel and biokerosene. The specific objective is to use a destructive method to develop allometric prediction equations of the aboveground biomass production of J. curcas plantations. 38 J. curcas shrubs were harvested and weighed in order to estimate biomass production. These data were used to develop allometric equations for the estimation of wood, leaf and total aboveground biomass production. The best-fit models found for estimating shrub component biomass and total aboveground biomass production were of the power form. All of the regression equations relating the prediction of leaf biomass, wood biomass and total aboveground biomass with J. curcas diameter at 20 cm above the ground (D) were statistically significant (p < 0.001) and also presented the highest goodness of fit (high R ²). The aboveground biomass carbon content was estimated using the ash method. Carbon content in leaves and wood was, respectively, 48 and 54 %. The current established allometric equations can be helpful to provide a rapid estimation of the aboveground biomass and C stock for J. curcas biofuel projects in semi-arid conditions.     

Experimental investigation of energy properties for Stigonematales sp. microalgae as potential biofuel feedstock

Microalgae has been considered potential biofuel source from the last decade owing to its versatile perspectives such as excellent capability of CO₂ capture and sequestration, water treatment, prolific growth rate and enormous energy content. Thus, energy research on microalgae is being harnessed to mitigate CO₂ and meet future energy demands. This study investigated the bioenergy potential of native blue-green microalgae consortium as initial energy research on microalgae in Brunei Darussalam. The local species of microalgae were assembled from rainwater drains, the species were identified as Stigonematales sp. and physical properties were characterised. Sundried biomass with moisture content ranging from 6.5% to 7.37% was measured to be used to determine the net and gross calorific value and they were 7.98 MJ/kg-8.57 MJ/kg and 8.70 MJ/kg-9.45 MJ/kg, respectively. Besides that, the hydrogen content, ash content, volatile matter, and bulk density were also experimented and they were 2.56%-3.15%, 43.6%-36.71%, 57–38%-63.29% and 661.2 kg/m³-673.07 kg/m³, respectively. Apart from experimental values, other physical bioenergy parameters were simulated and they were biomass characteristic index 61,822.29 kg/m³-62,341.3 kg/m³, energy density 5.27 GJ/m³-5.76G J/m³ and fuel value index 86.19–88.54. With these experimental results, microalgae manifested itself a potential source of biofuel feedstock for heat and electricity generation, a key tool to bring down the escalated atmospheric greenhouse gases and an alternation for fossil fuel.     

Performance evaluation of solar photovoltaic electricity-generating systems: an Indian perspective

The present work seeks to assess the sustainability of different solar photovoltaic (SPV) electricity-generating systems based upon energy, environment and economics. The sustainability indicators evaluated for energy, environment and economics are electrical output, life-cycle greenhouse gas (GHG) emissions and life-cycle cost of electricity generated per kilowatt hour. The selected SPV-based electricity generation technologies for sustainability evaluation are amorphous, monocrystalline and polycrystalline at different locations and tilt angles across India. For SPV systems, most of the emissions are the result of electricity use during manufacturing. In these cases, an average grid mix for the region of manufacture is typically used to calculate energy use and emissions. Based upon these three indicators, a figure of merit (FM) has been proposed. The results proposed that polycrystalline gives the maximum electrical output, minimum GHG emission, minimum cost and maximum FM at a radiation level of 6 kWh/m²/day with latitude and tilt angle of 34° and 35°, respectively. This work will be helpful to users of solar energy, academicians, researchers and other concerned persons, in understanding the importance, severity and benefits obtained by the application and implementation of the SPV electricity-generating systems.     

A data envelopment analysis approach to choose transport modes based on eco-efficiency

The main purpose of this paper is to use data envelopment analysis (DEA) as a support tool to establish a relative eco-efficiency measure for the different bioethanol transportation modes and to prioritize these different modes according to these figures. From a review of previous studies, we selected a set of attributes to be considered in DEA, and then experts were consulted about the importance of these attributes for this type of analysis in Brazil. To quantify the attributes, we established indicators and submitted them to DEA to evaluate the relative eco-efficiency to each available transportation mode for the case studied. The use of DEA established the guidelines to improve the transportation modes that were not considered 100?% relatively eco-efficient. These improvements could be achieved considering the percentage, reduction or growth for each of the attributes in the selected transportation mode. The proposed approach can help the Brazilian government to develop a plan to improve the bioethanol transportation infrastructure and can be used to propel short-term improvements in the highway transport of bioethanol, which could be useful given the Brazilian transportation context.     

Renewable biomass-derived lignin in transportation infrastructure strengthening applications

Lignin is considered as nature's most abundant aromatic polymer co-generated during papermaking and biomass fractionation. There are different types of lignins depending on the source (hardwood, softwood, annual crops, etc.) and recovery process. Recently, an emerging class of lignin products, namely sulphur-free lignins, from biomass conversion processes, solvent pulping and soda pulping, have generated interesting new applications owing to their versatility. As the renewable energy industry is expanding into developing the next generation of biofuels based on cellulosic biomass (e.g. corn stover, forest products waste, switch grass), abundant supply of sulphur-free lignin will become available as co-products for which value-added engineering applications are being sought. This paper discusses the potential for utilising lignin-containing biofuel co-products for stabilisation of geo-foundation beneath road pavements. Laboratory test results indicate that the biofuel co-products were effective in stabilising the Iowa class 10 soil (CL or A-6(8) soil classification). Utilisation of cellulosic biomass-derived lignin in transportation infrastructure strengthening applications appears to be one of the many viable answers to the profitability of the bio-based products and the bioenergy business from the perspectives of sustainable infrastructure systems.     

A strategic quantitative approach for sustainable energy production from biomass

European legislation has created a growing interest in the field of renewable energy production in several countries, including Italy. The applications of biomass and/or biofuel for energy generation have been assumed to provide a high level of sustainability due to the perception that renewable resources are inherently sustainable. Thus, renewable fuels applied to heating and/or electricity generation are potentially carbon dioxide neutral. However, before accepting this assumption, it is essential to analyse the actual level of sustainability in the whole supply chain (SC). This requirement has been clearly identified by the recently updated European Directives on renewable biofuels for transportation. However, there is little evidence that this concern has been directed at energy production from biomass. Thus, approaches derived from Green SC Management (GSCM) methods could provide an effective tool for evaluating, from a strategic perspective, the sustainability level of a specific biomass SC. This paper examines how biomass SC activities can define the overall environmental sustainability level. The approach was based on environmental indicators and the resultant output could support more effective GSCM strategies (e.g. defining logistics carriers, evaluating new biomass suppliers, etc.) for managing biomass SCs. Moreover, the approach could be applied by competent authorities for a quick evaluation of the sustainability level of biomass energy production installations. The approach has been tested in a real case study based on an installation, located in Southern Italy, which uses liquid biomass for energy production.     

Contribution of the sugar cane industry to reduce carbon dioxide emissions in the energy sector: the case of Mauritius

The aim of this paper was to present the contribution of the sugar cane industry to reduce carbon dioxide emissions in the energy sector. Mauritius is taken as a case study. Sugar cane was introduced in Mauritius during the seventeenth century and production of sugar started around 60 years later. Since then, the cane industry has been one of the economic pillars of the country. Bagasse, a by-product of sugar cane, is used as fuel in cogeneration power plants to produce process heat and electricity. This process heat and the generated electricity are used by an annexed sugar mills for the production of sugar, while the remaining electricity is exported to the national grid. In fact, Mauritius is a pioneer in the field of bagasse-based cogeneration power plant; the first bagasse-based cogeneration power plant that was commissioned in the world was in Mauritius in 1957. The contribution of the cane industry in the electricity sector has been vital for the economic development of Mauritius and also in terms of mitigating carbon dioxide emissions by displacing fossil fuels in electricity generation, as bagasse is classified as a renewable source. Data obtained from Statistics Mauritius on electricity production for the past 45 years were analysed, and carbon dioxide emissions were calculated based on international norms. It is estimated that savings on heavy fuel oil importation were by 1.5 million tons of oil—representing a value of 2.9 billion dollars—thus avoiding 4.5 million tons of carbon dioxide emissions. This figure can be further increased if molasses, a by-product of sugar cane juice, is used to produce bio-ethanol to be used as fuel in vehicles.     

Predicting hot-spots of land use changes in Italy by ensemble forecasting

In the context of environmental change projections at the regional level, not only the climate but also the land use plays a key role. The limited availability of historical information reduces the possibility to calibrate land use change (LUC) models. Even in case of successful calibration, using it both for diagnostic and prognostic studies does not guarantee the reliability of single future simulations. Through ensemble forecasting, useful LUC predictions are evaluable. In this work, after introducing a modified version of the well-assessed CLUE-S model, we present reasonable hot-spots of LUC in Italy for the end of 21st century, derived from the agreement of a 32 simulation ensemble performed alternating two choices for five model configurations or inputs: (1) two different climate projections (reflecting A2 and B2 emission scenarios by IPCC, respectively); (2) two different degrees (slight and strong) of demographic increase; (3) the conservation (or not) of protected areas; (4) the influence (or not) among adjacent land uses in determining their shift; and (5) the importance (or not) of past/recent LUC trends. Results, in terms of LUC hot-spot distribution, were evaluated at administrative, biogeographical, physiographic, and watershed level. The main findings highlighted that some trends of land use substitution will be likely opposite to the past and that a more detailed spatial scale can detect situations neglected by coarser scale evaluations, and due to different transpositions of directives from high-levels to local scales. Biogeographical and physiographic settings seem strongly influencing LUCs, and administrative and catchment units across Italy show very different developments and a highly fragmented territory in terms of LUC hot-spots, all that to be considered in landscape and resource planning.     

Farm-level assessment of CO2 and N2O emissions in Lower Saxony and comparison of implementation potentials for mitigation measures in Germany and England

Greenhouse gases (GHG) emissions from agricultural farming practice contribute significantly to European GHG inventories. For example, CO₂ is emitted when grassland is converted to cropland or when peatlands are drained and cultivated. N₂O emissions result from fertilization. Enabling farmers to reduce their GHG emissions requires sufficient information about its pressure–impact relations as well as incentives, such as regulations and funding, that support climate-friendly agricultural management. This paper discusses potentials to improve the supply of information on: farm-specific climate services or impacts, present policy incentives in Germany and England that support climate-friendly farm management and related adaptation requirements. Tools which have been developed for a farm environmental management software (to be added after review because of potential identification) are presented. These tools assess CO₂ emissions from grassland conversion to cropland and peatland cultivation, as well as N₂O emissions from nitrogen fertilization. As input data, the CO₂ tool requires a classification of soil types according to soil organic carbon storage. The input data based on soil profile samples was compared with reference data from the literature. The N₂O tool relies on farm data concerning fertilization. These tools were tested on three farms in order to determine their viability with respect to the availability of required data and the differentiation of results, which determines how well site-specific conservation measures can be identified. Assessing CO₂ retention function of grassland conservation to cropland on the test farms leads to spatially differentiated results (~100 to ~900 potentially mitigated t CO₂ ha^?1). Assessed N₂O emissions varied from 0.41 to 1.1 t CO₂eq. ha^?1 a^?1. The proposed methods support policies that promote a more differentiated funding of climate conservation measures. Conservation measures and areas can be selected so that they will have the greatest mitigation effects. However, even though present policy instruments in Germany and England, such as Cross Compliance and agri-environmental measures, have the potential to reduce agricultural GHG, they do not appear to guide measures effectively or site-specifically. In order to close this gap, agri-environmental measures with the potential to support climate protection should be spatially optimized. Additionally, the wetland restoration measures which are most effective in reducing GHG emissions should be included in funding schemes.     

Production of renewable and sustainable fuel from Calliandra calothyrsus and its utilisation in compression ignition engines

Alternative fuels have several advantages compared to fossil fuels as they are renewable, biodegradable, provide energy security, foreign exchange saving as well as help in addressing environmental concerns and socio-economic issues. Therefore, renewable fuels can be used predominantly as a fuel for transportation and for applications in power generation. Shaft power application is a key factor for economic growth and prosperity and depends crucially on the long-term availability of energy from sources that are affordable, accessible and environmentally friendly. In this context, the main objective of the present study was to implement the production of bioethanol from Calliandra calothyrsus, a potential lignocellulosic raw material for the cellulose-to-bioethanol conversion process that can be used as an alternative resource to starch- or sugar-containing feedstock. This study addresses a new pretreatment method known as hydrothermal explosion using C. calothyrsus for ethanol production. The present study also involves experimental investigations on a single-cylinder, four-stroke, direct-injection diesel engine operated with Honge oil methyl ester (biodiesel) and ethanol and its comparison with a neat diesel fuel mode of operation. The results revealed that optimal parameters for bioethanol production from C. calothyrsus were 2% acid concentration (HCl), 100°C temperature and 80 min retention time. For a diesel engine operated with a HOME–bioethanol blend, the experimental results showed a 3–4% decrease in brake thermal efficiency with a 8–10% increase in hydrocarbon and carbon monoxide emission levels and a 15–18% decrease in nitric oxide emission levels when compared with a neat diesel fuel mode of operation.     

Assessment of uncertainties in greenhouse gas emission profiles of livestock sectors in Africa,Latin America and Europe

The global animal food chain has a large contribution to the global anthropogenic greenhouse gas (GHG) emissions, but its share and sources vary highly across the world. However, the assessment of GHG emissions from livestock production is subject to various uncertainties, which have not yet been well quantified at large spatial scale. We assessed the uncertainties in the relations between animal production (milk, meat, egg) and the CO₂, CH₄, and N₂O emissions in Africa, Latin America and the European Union, using the MITERRA-Global model. The uncertainties in model inputs were derived from time series of statistical data, literature review or expert knowledge. These model inputs and parameters were further divided into nine groups based on type of data and affected greenhouse gas. The final model output uncertainty and the uncertainty contribution of each group of model inputs to the uncertainty were quantified using a Monte Carlo approach, taking into account their spatial and cross-correlation. GHG emissions and their uncertainties were determined per livestock sector, per product and per emission source category. Results show large variation in the GHG emissions and their uncertainties for different continents, livestock sectors products or source categories. The uncertainty of total GHG emissions from livestock sectors is higher in Africa and Latin America than in the European Union. The uncertainty of CH₄ emission is lower than that for N₂O and CO₂. Livestock parameters, CH₄ emission factors and N emission factors contribute most to the uncertainty in the total model output. The reliability of GHG emissions from livestock sectors is relatively high (low uncertainty) at continental level, but could be lower at country level.     

中国城市温室气体清单研究

介绍城市温室气体排放特征和国际城市温室气体清单研究进展,研究了全球城市化和城市CO2排放的强正相关性,以及中国城市清单方法研究起步较早但发展缓慢的特点。分析了城市温室气体清单相对国家清单的特征,即城市清单编制往往采用消费模式,区别于国家清单的生产模式;国际城市清单中往往包括了由于外调电和供暖产生的CO2排放,同时城市温室气体清单编制灵活性和针对性更强。针对我国城市温室气体清单研究的不足,提出了我国城市温室气体清单方法,强调中国城市采用尺度1+尺度2的范围,暂不考虑尺度3的范围,即生产+消费的混合模式,并且在城市市域温室气体排放研究的基础上,加强狭义城市温室气体排放水平的研究。选择北京市和纽约市,对比分析了两个城市CO2排放特征,结果显示,在确定的清单体系下,北京市和纽约市具有较好的可比性。纽约市的总排放量(尺度1+尺度2)略低于北京市排放量,人均排放量略高于北京市。     

Economical sensitivity analysis of rice husk utilization in a 300 kW<Subscript>el</Subscript> Micro Thermal Power Plant

Production of rice husks in Rio Grande do Sul State, which is the major rice production state in Brazil, needs to be adequately managed to diminish environmental impacts. A Micro Thermal Power Plant (MTP), which is a compact and small-scale biomass thermal power plant technology, can be used in electricity generation in thermal power plants with a power capacity up to 800 kW_el. This paper presents a feasibility analysis of a 300 kW_el MTP that is fuelled by rice husks using two different scenarios: the autoproduction (Case 1) and the independent production (Case 2) of electricity. Both scenarios were found to be unfeasible. Therefore, a sensitivity analysis is performed to evaluate the variables that affect feasibility, such as the electricity commercialization price, the value of certified emission reductions and the financial interest rates. According to sensitivity analysis, small-scale thermal power plants could have feasibility if they received incentives through government programmes, such as through the exemption of equipment taxes and/or the reduction or elimination of the financial interest rate.     

Mitigation of greenhouse gas emissions from an abandoned Baltic peat extraction area by growing reed canary grass: life-cycle assessment

Abandoned peat extraction areas are continuous emitters of GHGs; hence, abandonment of peat extraction areas should immediately be followed by conversion to an appropriate after-use. Our primary aim was to clarify the atmospheric impact of reed canary grass (RCG, Phalaris arundinacea L.) cultivation on an abandoned peat extraction area and to compare it to other after-treatment alternatives. We performed a life-cycle assessment for five different after-use options for a drained organic soil withdrawn from peat extraction: (I) bare peat soil (no management), (II) non-fertilised Phalaris cultivation, (III) fertilised Phalaris cultivation, (IV) afforestation, and (V) rewetting. Our results showed that on average the non-fertilised and fertilised Phalaris alternatives had a cooling effect on the atmosphere (?10,837 and ?477 kg CO₂-eq ha^?1 year^?1, respectively), whereas afforestation, rewetting, and no-management alternatives contributed to global warming (9,511, 8,195, and 2,529 kg CO₂-eq ha^?1 year^?1, respectively). The main components influencing the global warming potential of different after-use alternatives were site GHG emissions, carbon assimilation by plants, and emissions from combustion, while management-related emissions played a relatively minor role. The results of this study indicate that, from the perspective of atmospheric impact, the most suitable after-use option for an abandoned peat extraction area is cultivation of RCG.     

重庆市温室气体排放清单研究与核算

城市化进程所带来的大量能源消费和温室气体排放已成为制约城市健康快速发展的瓶颈因素,亟需进行定量核算和分析。开展温室气体清单研究对节能减排和低碳城市建设具有重要的理论和实践意义。本文以重庆市为案例,通过清单方法分析主要温室气体排放源和碳汇,考虑主要能源活动、工业、废弃物处置、农业、畜牧业、湿地过程和林业碳汇,核算排放总量和强度,剖析重庆温室气体排放结构和现状。结果显示:1997-2008年重庆市温室气体排放总量呈现出上升趋势,2008年比1997年增长了2.31倍,其中增长幅度较大的是一次能源消费过程、外购电力和工业非能源过程。此外,随着温室气体排放量的增加,单位产值温室气体排放量却呈现下降的趋势,反映重庆市温室气体排放控制取得了一定效果。最后根据重庆市温室气体排放结果进行分析,提出了改变能源结构和工业结构、提高能效和加强"森林重庆"建设等政策建议,为重庆市转型低碳经济发展提供参考。     

Impact of climatic conditions on irrigation water requirements and hydraulic characteristics of modern irrigation systems

Irrigation system performance regards as a function of climatic conditions. The present study was carried out to study this phenomenon. Sugar beet and sesame corps were cultivated during two agricultural seasons of 2017/2018 and 2018/2019 irrigated with drip and sprinkler systems. The drip and sprinkler systems performance was evaluated in terms of hydraulic characteristics added to irrigation water requirements. The recorded monthly values were compared to the traditional estimation method. The results revealed that irrigation system efficiency was increased by increasing ambient temperature for the drip irrigation system, and vice versa was noticed with the sprinkler irrigation system. Emission uniformity and application efficiency of emitters were increased by increasing ambient temperature. While the sprinkler flow rate and distribution uniformity were decreased by increasing ambient temperature. For drip irrigation system, the average total amount of irrigation water requirements using traditional estimation for sugar beet (2372 m³/fed) was less than the actual calculated (2439 m³/fed), while for sesame crop, the traditional estimation method (2556 m³/fed) was higher than actual calculated (2477 m³/fed). Using a sprinkler system, the average total amount of irrigation water requirements by the traditional estimation (2689 and 2897 m³/fed) was less than the actual calculated (2709 and 3044 m³/fed) for sugar beet and sesame crops, respectively. So, it is important to consider the effects of climatic conditions through the agricultural season.

     

Technological feasibility and costs of achieving a 50 % reduction of global GHG emissions by 2050: mid- and long-term perspectives

In this article we examine the technological feasibility of the global target of reducing GHG emissions to 50 % of the 1990 level by the year 2050. We also perform a detailed analysis of the contribution of low-carbon technologies to GHG emission reduction over mid- and long-term timeframes, and evaluate the required technological cost. For the analysis we use AIM/Enduse[Global], a techno-economic model for climate change mitigation policy assessment. The results show that a 50 % GHG emission reduction target is technically achievable. Yet achieving the target will require substantial emission mitigation efforts. The GHG emission reduction rate from the reference scenario stands at 23 % in 2020 and 73 % in 2050. The marginal abatement cost to achieve these emission reductions reaches 150/tCO < sub > 2 < /sub > -eq in 2020 and150/tCO₂-eq in 2020 and 600/tCO₂-eq in 2050. Renewable energy, fuel switching, and efficiency improvement in power generation account for 45 % of the total GHG emission reduction in 2020. Non-energy sectors, namely, fugitive emission, waste management, agriculture, and F-gases, account for 25 % of the total GHG emission reduction in 2020. CCS, solar power generation, wind power generation, biomass power generation, and biofuel together account for 64 % of the total GHG emission reduction in 2050. Additional investment in GHG abatement technologies for achieving the target reaches US6.0 trillion by 2020 and US 6.0 trillion by 2020 and US 73 trillion by 2050. This corresponds to 0.7 and 1.8 % of the world GDP, respectively, in the same periods. Non-Annex I regions account for 55 % of the total additional investment by 2050. In a sectoral breakdown, the power generation and transport sectors account for 56 and 30 % of the total additional investment by 2050, respectively.     

Land use and cover dynamics in Africa since the nineteenth century: warped terrestrial photographs of North Ethiopia

Quantitative research on land use and land cover (LUC) in Africa usually addresses the second half of the twentieth century, by using remote sensing data. Terrestrial photographs, which are available since 1868 in Ethiopia, are seldom used in a quantitative way. This paper presents a methodology that allows to produce land use and land cover (LUC) maps on the basis of old terrestrial photographs. Therefore, land use and land cover was investigated on historical and present-day photographs, and these interpretations were warped to the horizontal plane of the map. The resulting maps allow to gain better insights into LUC changes over a period of 140 years. The results show that woody vegetation increased strongly, together with an increase in built-up area. This occurred especially at the expense of bushland. The study validates pervious findings and shows that improved land management strategies in one of the world’s most degraded areas can lead to environmental rehabilitation.