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South Africa’s energy network is under severe pressure due to low supply and overwhelming demand. With an increase in renewable energy providers, specifically wind energy, knowing how the supply can satisfy the electricity demand may relieve apprehensions. This research aims to provide insight into the wind energy supply of South Africa and question how well this supply meets the demand of South Africa. The methodology used in this work highlights the importance of access to public datasets to dispel misconceptions in the energy industry. Additionally, the work supports network planning and the arguments for increasing wind energy penetration on the South African grid. Wind profiles and the typical energy production of South African wind farms are compared to electricity demand. The geographical spacing of the operational wind farms is considered. It is observed that wind energy supply assists in the peak electricity hourly demand as well as seasonal peaks. Furthermore, South Africa’s coast is analysed to determine the offshore wind power potential, where shallow and deep waters are considered. It is observed that South Africa has a high potential for offshore wind, even after losses are applied.

Historically, human uses of land have transformed and fragmented ecosystems 1 , 2 , degraded biodiversity 3 , 4 , disrupted carbon and nitrogen cycles 5 , 6 and added prodigious quantities of greenhouse gases (GHGs) to the atmosphere 7 , 8 . However, in contrast to fossil-fuel carbon dioxide (CO 2 ) emissions, trends and drivers of GHG emissions from land management and land-use change (together referred to as ‘land-use emissions’) have not been as comprehensively and systematically assessed. Here we present country-, process-, GHG- and product-specific inventories of global land-use emissions from 1961 to 2017, we decompose key demographic, economic and technical drivers of emissions and we assess the uncertainties and the sensitivity of results to different accounting assumptions. Despite steady increases in population (+144 per cent) and agricultural production per capita (+58 per cent), as well as smaller increases in emissions per land area used (+8 per cent), decreases in land required per unit of agricultural production (–70 per cent) kept global annual land-use emissions relatively constant at about 11 gigatonnes CO 2 -equivalent until 2001. After 2001, driven by rising emissions per land area, emissions increased by 2.4 gigatonnes CO 2 -equivalent per decade to 14.6 gigatonnes CO 2 -equivalent in 2017 (about 25 per cent of total anthropogenic GHG emissions). Although emissions intensity decreased in all regions, large differences across regions persist over time. The three highest-emitting regions (Latin America, Southeast Asia and sub-Saharan Africa) dominate global emissions growth from 1961 to 2017, driven by rapid and extensive growth of agricultural production and related land-use change. In addition, disproportionate emissions are related to certain products: beef and a few other red meats supply only 1 per cent of calories worldwide, but account for 25 per cent of all land-use emissions. Even where land-use change emissions are negligible or negative, total per capita CO 2 -equivalent land-use emissions remain near 0.5 tonnes per capita, suggesting the current frontier of mitigation efforts. Our results are consistent with existing knowledge—for example, on the role of population and economic growth and dietary choice—but provide additional insight into regional and sectoral trends. Trends in the rate of region- and sector-specific land-use greenhouse gas emissions in 1961–2017 show an acceleration of about 20% per decade after 2001.

River deltas rank among the most economically and ecologically valuable environments on Earth. Even in the absence of sea-level rise, deltas are increasingly vulnerable to coastal hazards as declining sediment supply and climate change alter their sediment budget, affecting delta morphology and possibly leading to erosion 1 – 3 . However, the relationship between deltaic sediment budgets, oceanographic forces of waves and tides, and delta morphology has remained poorly quantified. Here we show how the morphology of about 11,000 coastal deltas worldwide, ranging from small bayhead deltas to mega-deltas, has been affected by river damming and deforestation. We introduce a model that shows that present-day delta morphology varies across a continuum between wave (about 80 per cent), tide (around 10 per cent) and river (about 10 per cent) dominance, but that most large deltas are tide- and river-dominated. Over the past 30 years, despite sea-level rise, deltas globally have experienced a net land gain of 54 ± 12 square kilometres per year (2 standard deviations), with the largest 1 per cent of deltas being responsible for 30 per cent of all net land area gains. Humans are a considerable driver of these net land gains—25 per cent of delta growth can be attributed to deforestation-induced increases in fluvial sediment supply. Yet for nearly 1,000 deltas, river damming 4 has resulted in a severe (more than 50 per cent) reduction in anthropogenic sediment flux, forcing a collective loss of 12 ± 3.5 square kilometres per year (2 standard deviations) of deltaic land. Not all deltas lose land in response to river damming: deltas transitioning towards tide dominance are currently gaining land, probably through channel infilling. With expected accelerated sea-level rise 5 , however, recent land gains are unlikely to be sustained throughout the twenty-first century. Understanding the redistribution of sediments by waves and tides will be critical for successfully predicting human-driven change to deltas, both locally and globally. A global study of river deltas shows a net increase in delta area by about 54 km 2  yr −1 over the past 30 years, in part due to deforestation-induced sediment delivery increase.

Import and export of fossil energy carriers are cornerstones of energy systems world-wide. If energy systems are to become climate neutral and sustainable, fossil carriers need to be substituted with carbon neutral alternatives or electrified if possible. We investigate synthetic chemical energy carriers, hydrogen, methane, methanol, ammonia and Fischer-Tropsch fuels, produced using electricity from Renewable Energy Source (RES) as fossil substitutes. RES potentials are obtained from GIS-analysis and hourly resolved time-series are derived using reanalysis weather data. We model the sourcing of feedstock chemicals, synthesis and transport along nine different Energy Supply Chains to Germany and compare import options for seven locations around the world against each other and with domestically sourced alternatives on the basis of their respective cost per unit of hydrogen and energy delivered. We find that for each type of chemical energy carrier, there is an import option with lower costs compared to domestic production in Germany. No single exporting country or energy carrier has a unique cost advantage, since for each energy carrier and country there are cost-competitive alternatives. This allows exporter and infrastructure decisions to be made based on other criteria than energy and cost. The lowest cost means for importing of energy and hydrogen are by hydrogen pipeline from Denmark, Spain and Western Asia and Northern Africa starting at 36 EUR/MWh LHV to 42 EUR/MWh LHV or 1.0 EUR/kg H2 to 1.3 EUR/kg H2 (in 2050, assuming 5% p.a. capital cost). For complex energy carriers derived from hydrogen like methane, ammonia, methanol or Fischer-Tropsch fuels, imports from Argentina by ship to Germany are lower cost than closer exporters in the European Union or Western Asia and Northern Africa. For meeting hydrogen demand, direct hydrogen imports are more attractive than indirect routes using methane, methanol or ammonia imports and subsequent decomposition to hydrogen because of high capital investment costs and energetic losses of the indirect routes. We make our model and data available under open licenses for adaptation and reuse.

Urban populations are highly vulnerable to the adverse effects of heat, with heat-related mortality showing intra-urban variations that are likely due to differences in urban characteristics and socioeconomic status. We investigated the influence of urban green and urban blue, that is, urban vegetation and water bodies, on heat-related excess mortality in the elderly > 65 years old in Lisbon, Portugal, between 1998 and 2008. We used remotely sensed data and geographic information to determine the amount of urban vegetation and the distance to bodies of water (the Atlantic Ocean and the Tagus Estuary). Poisson generalized additive models were fitted, allowing for the interaction between equivalent temperature [universal thermal climate index (UTCI)] and quartiles of urban greenness [classified using the Normalized Difference Vegetation Index (NDVI)] and proximity to water (≤ 4 km vs. > 4 km), while adjusting for potential confounders. The association between mortality and a 1°C increase in UTCI above the 99th percentile (24.8°C) was stronger for areas in the lowest NDVI quartile (14.7% higher; 95% CI: 1.9, 17.5%) than for areas in the highest quartile (3.0%; 95% CI: 2.0, 4.0%). In areas > 4 km from water, a 1°C increase in UTCI above the 99th percentile was associated with a 7.1% increase in mortality (95% CI: 6.2, 8.1%), whereas in areas ≤ 4 km from water, the estimated increase in mortality was only 2.1% (95% CI: 1.2, 3.0%). Urban green and blue appeared to have a mitigating effect on heat-related mortality in the elderly population in Lisbon. Increasing the amount of vegetation may be a good strategy to counteract the adverse effects of heat in urban areas. Our findings also suggest potential benefits of urban blue that may be present several kilometers from a body of water. Burkart K, Meier F, Schneider A, Breitner S, Canário P, Alcoforado MJ, Scherer D, Endlicher W. 2016. Modification of heat-related mortality in an elderly urban population by vegetation (urban green) and proximity to water (urban blue): evidence from Lisbon, Portugal. Environ Health Perspect 124:927-934; http://dx.doi.org/10.1289/ehp.1409529.

Tripura is a water-rich administrative state in the Northeastern part of India. Though groundwater is the main source of drinking water, groundwater monitoring and historical data on the groundwater quality of this state is relatively scarce. This study aims to identify the sources and processes controlling the hydrochemical evolution of groundwater in Hezamara block in Tripura. Interpretation of measured parameters using geochemical plots, analysis of ionic ratios, multivariate statistical techniques, and spatial interpolation methods indicated both natural and anthropogenic sources. Results show that precipitation is the dominant process controlling the groundwater quality followed by rock–water interaction. Carbonate dissolution and silicate weathering were the major geochemical processes. The findings showed that the concentration of few heavy metals (iron, manganese, and lead) exceeded the drinking water quality standards. Evaluation of the results through various heavy-metal indices showed that several locations exceeded the limits and pose a risk to humans. Potential non-carcinogenic risk through the drinking water pathway was also identified. Pollution mapping indicates that only less than 1 km2 of the study area is suitable for drinking use. This study recommends installation of public drinking water supply in this area to reduce the impact of heavy-metal contamination on human health. Moreover, the water should be treated before supplying for public use.

PurposeThe study investigates how supply base structural complexity influences both supply chain agility and resilience. It employs Normal Accident Theory and Portfolio Theory to disentangle the effects of three structural facets of complexity – numerousness; technical and functional diversity; geographical distribution of suppliers – on the two capabilities simultaneously.Design/methodology/approachThe study is grounded in the Italian footwear industry. 31 manufacturing firms with their global supply base have provided a cross-sectional time series database over a 10-year period (310 observations).FindingsThe results show that supply base numerousness has nonlinear effects on both supply chain agility and resilience. The directions of these effects are opposites. They also show that supply base diversity has an inverted U-shaped effect on supply chain agility while it is insignificant for resilience. Finally, the results show that suppliers' geographical dispersion is detrimental to both capabilities.Originality/valueThis is the first study that considers the multifaceted effects of supply base complexity on both supply chain agility and resilience. In doing so, it also sheds light on some of the most common trade-offs that firms address when they seek a balance between different strategies, such as increasing agility without damaging supply base resilience and vice versa. Considering the resource constraints firms normally face, by disentangling the dual effects of each complexity facet, this study helps decision-makers to develop scalability and leverage the supply base characteristics in order to survive and prosper in uncertain markets.

River basins in Odisha suffer from serious anthropogenic interventions that degrade water quality, including runoff from agriculture, municipal wastewater, and industrial discharges. The Brahmani River, an essential source of water for industrial, agricultural, and drinking uses, is especially affected by overuse of fertilizer and pesticides. Ensuring health and cleanliness in cities and communities requires constant monitoring and management of drinking water sources. This study evaluates the river’s water quality for drinking and agricultural applications and identifies key factors influencing its deterioration. Water samples were collected from 12 locations during pre-monsoon (PRM) and post-monsoon (POM) seasons (2017–2021) and analyzed for physicochemical parameters against World Health Organization (WHO) standards. For quality assessment, values of analyzed parameters of the surface water samples were compared with the WHO water quality standards. The findings show that the majority of the samples are fit for drinking and irrigation, with the main cations arranged as Ca 2 ⁺ > Na⁺ > Mg 2 ⁺ > K⁺ and anions as HCO₃⁻ > Cl⁻ > SO₄ 2 ⁻ > CO₃ 2 ⁻, respectively. The analytical results indicate slightly alkaline nature of the surface water in the study area. Strong correlations among ions (HCO₃⁻, Ca 2 ⁺, Mg 2 ⁺, Cl⁻, SO₄ 2 ⁻) suggest influences from natural processes (weathering, erosion) and anthropogenic activities. Seasonal variations assessed using Water Quality Index (WQI) and Canadian Council of Ministers of the Environment Water Quality Index (CCME-WQI) method indicate that water quality ranges from good to poor in PRM and good to marginal in POM seasons. The metrics and the criteria differ significantly, indicating that remedial action is necessary to enhance the quality of the water at these locations. Irrigation suitability indices (SAR, MH, %Na, PI, RSC, KI, ESP) further confirm the water’s acceptability for agricultural use. The irrigation suitability of agriculture-dominated basin was assessed using Empirical Bayesian Kriging (EBK) modeling, achieving high accuracy with an RMSS error and an MS error. Spatial maps generated using Geographical Information System (GIS) software, along with Gibbs plots, Piper diagrams, and Wilcox diagrams, help delineate agricultural zones and highlight the dominant geochemical processes. The study concludes that both anthropogenic (sewage discharge, waste dumping) and geogenic (evaporation, mineral dissolution) factors significantly affect water quality. The findings highlight the effectiveness of EBK for sustainable irrigation and agriculture. To preserve this critical resource, measures such as reducing sewage outflows, managing stormwater discharge, and preventing solid waste disposal are essential. The purpose of this study is to pinpoint areas with low water quality and offer workable solutions to the nation’s water resources management agency in order to enhance the drinking water supply or attain sustainable water resources. Findings revealed greater water stress in upstream areas compared to downstream regions, offering valuable insights for drinking, irrigation management, and drought-resistant crop planning. Graphical abstract

Potentially toxic elements (PTEs), especially arsenic in drinking water, pose significant global health risks, including cancer. This study evaluates the groundwater quality in Giresun province on the Black Sea coast of Türkiye by analyzing twelve groundwater resources. The mean concentrations of macronutrients (mg/L) were: Ca (10.53 ± 6.63), Na (6.81 ± 3.47), Mg (3.39 ± 2.27), and K (2.05 ± 1.10). The mean levels of PTEs (µg/L) were: Al (40.02 ± 15.45), Fe (17.65 ± 14.35), Zn (5.63 ± 2.59), V (4.74 ± 5.85), Cu (1.57 ± 0.81), Mn (1.02 ± 0.76), As (0.93 ± 0.73), Cr (0.75 ± 0.57), Ni (0.41 ± 0.18), Pb (0.36 ± 0.23), and Cd (0.10 ± 0.05). All PTE levels complied with WHO drinking water safety guidelines, and overall water quality was excellent. The heavy metal evaluation index (HEI < 10) and heavy metal pollution index (HPI < 45) indicate low pollution levels across all stations. Irrigation water quality was largely adequate, as shown by the magnesium hazard (MH), sodium adsorption ratio (SAR), Na%, and Kelly's ratio (KR). The total hazard index (THI) values consistently remained below 1, indicating no non-carcinogenic health risks. However, at station 10 (city center), the cancer risk (CR) for adults due to arsenic was slightly above the threshold (1.44E-04). Using principal component analysis (PCA), positive matrix factorization (PMF), and geographic information system (GIS) mapping, the study determined that most PTEs originated from natural geological formations or a combination of natural and human sources, with minimal impact from human activities. These findings highlight the safety and reliability of the groundwater sources studied, emphasizing their potential as a long-term, safe water supply for nearby populations.

This qualitative study sought to understand food acquisition behaviors and environmental factors that influence those behaviors among women in a low-income African American community with limited food resources. We drew on in-depth interviews with 30 women ages 21 to 45 years recruited from a community health center in Chicago, Illinois. Data were analyzed using qualitative content analysis. Emergent themes revealed that women identified multiple environmental barriers—material, economic, and social-interactional—to acquiring food in an acceptable setting. In response, they engaged in several adaptive strategies to manage or alter these challenges, including optimizing, settling, being proactive, and advocating. These findings indicate that efforts to improve neighborhood food environments should address not only food availability and prices but also the physical and social environments of stores.