Land-use change and its socio-environmental impact in Eastern Ethiopia’s highland

The Alemaya district (Eastern Ethiopian highlands) is characterized by undulating physiographic features with arid, semi-arid, and humid climatic conditions. This study evaluated socio-environmental changes in land use and land cover during 1985–2011. Screen digitization on remotely sensed data (i.e., Landsat images from 1985 to 2011) was performed to produce 10 classes of land use and land cover. Then, final land-use maps were prepared using a geographic information system following field verification and accuracy assessment. The drying of water bodies, including the prominent lakes Alemaya, Adele, and Tinike, had been the most important environmental change observed. Degraded land, marsh, perennial cropland, and residential areas increased by 37, 438, 42, and 190 %, respectively, whereas grassland, plantation, shrubland, and temporal cropland decreased by 64, 11, 63, and 29 %, respectively. The increase in land degradation (+37 %), the other major observed problem, has made large areas unsuitable for agriculture and has reduced crop productivity. These land-use and land-cover changes have affected both the environment and the livelihoods of local residents; especially the issue related to land degradation requires urgent attention.     

The need for integration of drought monitoring tools for proactive food security management in sub‐Saharan Africa

Reducing the impact of drought and famine remains a challenge in sub‐Saharan Africa despite ongoing drought relief assistance in recent decades. This is because drought and famine are primarily addressed through a crisis management approach when a disaster occurs, rather than stressing preparedness and risk management. Moreover, drought planning and food security efforts have been hampered by a lack of integrated drought monitoring tools, inadequate early warning systems (EWS), and insufficient information flow within and between levels of government in many sub‐Saharan countries. The integration of existing drought monitoring tools for sub‐Saharan Africa is essential for improving food security systems to reduce the impacts of drought and famine on society in this region. A proactive approach emphasizing integration requires the collective use of multiple tools, which can be used to detect trends in food availability and provide early indicators at local, national, and regional scales on the likely occurrence of food crises. In addition, improving the ability to monitor and disseminate critical drought‐related information using available modern technologies (e.g., satellites, computers, and modern communication techniques) may help trigger timely and appropriate preventive responses and, ultimately, contribute to food security and sustainable development in sub‐Saharan Africa.     

Adsorption of As(III) versus As(V) from aqueous solutions by cerium-loaded volcanic rocks

Environmental Science and Pollution Research - Contamination of drinking water with arsenic causes severe health problems in various world regions. Arsenic exists predominantly as As(III) and As(V)...     

Open space index: a GIS-based tool for assessing human penetration of a landscape

In light of the rapid and continuous growth of the built environment worldwide and its attendant ecological impact, increasing the size and distribution of open space in urban areas is recognised as one effective way to reconcile the social and ecological objectives of society. However, there is no simple and objective indicator to measure open space that can be used for creating and maintaining sustainable landscapes. The paper introduces a metric, open space index (OSI), that measures the amount of space unpenetrated by the built environment. The metric is calculated by measuring the shortest distance between any location and the nearest built environment using a Geographic Information System. The metric is illustrated using two counties of the greater Twin Cities Metropolitan Region of Minnesota. The sensitivity of OSI to the size, shape, and spatial configuration of the built environment suggests that the metric can serve as an important planning tool for reconciling conservation and development in a wide range of contexts.     

Investing in climate change adaptation and mitigation: A methodological review of real-options studies

Uncertain future payoffs and irreversible costs characterize investment in climate change adaptation and mitigation. Under these conditions, it is relevant to analyze investment decisions in a real options framework, as this approach takes into account the economic value associated with investment time flexibility. In this paper, we provide an overview of the literature adopting a real option approach to analyze investment in climate change adaptation and mitigation, and examine how the uncertain impacts of climate change on the condition of the human environment, risk preferences, and strategic interactions among decisions-makers have been modeled. We found that the complex nature of uncertainties associated with climate change is typically only partially taken into account and that the analysis is usually limited to decisions taken by individual risk neutral profit maximizers. Our findings call for further research to fill the identified gaps.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01342-8) contains supplementary material, which is available to authorized users.