Ra–Po–Pb isotope systematics in waters of Sambhar Salt Lake,Rajasthan (India): geochemical characterization and particulate reactivity

The Sambhar Salt Lake hydrological system, including river waters, groundwaters, evaporating pans and sub-surface brines, has been analyzed for the salt content (TDS) and naturally occurring radionuclides (²¹⁰Po, ²¹⁰Pb and ^226,228Ra). The abundance of these radionuclides and their activity ratios show a wide variation in different hydrological regimes, which helps to geochemically characterize the lake system. A significantly lower Ra to total dissolved solids (TDS) ratio in the brines (by two to three orders of magnitude), when compared to the groundwaters and river waters, suggests removal of dissolved Ra by co-precipitation with Ca–Mg minerals at an early stage of the brine evolution. The concentration of Ra in evaporating lake/pan waters saturates at a value of about 35 Bq L⁻¹ over the salinity range of 100–370 g L⁻¹; attributable to its equilibration with the clay minerals. The two distinct regimes, saline lake system (lake water, evaporating pans and sub-surface brines) and groundwaters have been identified based on their differences in the distribution of ^226,228Ra isotopes. This observation points to the conclusion that the groundwaters and the lake brines are not intimately coupled in terms of their origin and evolution. The abundances of ²¹⁰Po and ²¹⁰Pb along with their activity ratios (²¹⁰Po/²¹⁰Pb) are markedly different among the surface lake waters/evaporating pans, sub-surface lake brines and groundwaters. These differences are explained in terms of different geochemical behaviour of these nuclides in presence of algae and organic matter present in these water regimes.     

Natural organic matter in drinking water — The “NOM-typing project”, background and basic characteristics of original water samples and NOM isolates

The complex nature of natural organic matter (NOM), and the impact of this matter on drinking water quality, necessitate international co-operative efforts. After several decades of struggle, many experienced NOM scientists world wide recognize the need for international sample references, or better yet, to work together on the same set of samples. The aim of the “NOM-typing project” was a multi-method characterization of a limited number of NOM samples, isolated from different water sources. The background of the project and the nature of the sampling sites are described here, and some data comparing the composition of the samples, before and after the isolation, are presented. The techniques used for isolation were reverse osmosis (RO) and evaporation (EVA). The NOM samples were isolated from eight different locations in the southern part of Norway. The nature of the corresponding catchments differs, however, all samples were from areas with no influence of agriculture or local industry. The key issue of the project was that all samples were isolated with exactly the same methods and by the same team. In spite of the uniformity of the isolation technique used for the nine samples, the recoveries of the material differ from sample to sample. Generally, the loss of NOM is in the range of 10%, however, for one sample, the loss was as high as 35%. These discrepancies are probably partly because of differences in the nature of the NOM and partly due to differences in the general composition of the ambient water. There are a few remarkable differences between the nine samples. There was a high percentage of ash in isolates from acidified areas. These are also the samples where the loss of NOM during the isolation process was highest. The density of the RO-isolates differs 10-fold between the samples. The lipophilisity of the NOM samples, expressed as relative solubility in octanol, differs more than 30-fold.     

Natural radionuclides in drinking water supplies of São Paulo State, Brazil and consequent population doses

The activity concentrations of 228Ra, 226Ra and 222Rn have been analysed in 452 drinking water supplies of S?o Paulo State. This study started in 1994 and covered 54% of the 574 existing counties. Concentrations up to 235 and 131 mBq l-1 were observed for 226Ra and 228Ra, respectively, whereas 222Rn concentrations reached 315 Bq l-1. Radiation doses up to 0.3, 0.6 and 3.2 mSv yr-1 were estimated for the critical organs, for the ingestion of 226Ra, 226Ra and 222Rn, respectively. The corresponding committed effective doses reached values of 6 x 10(-3), 2 x 10(-2) and 3 x 10(-1) mSv yr-1, for the same radionuclides. These results indicate that 222Rn makes the highest contribution to the total effective dose.     

Migration of Cs in tributaries,lake water and sediment of Lago Maggiore (Italy,Switzerland) – analysis and comparison with Lago di Lugano and other lakes

This paper describes the behaviour of ¹³⁷Cs in Lago Maggiore and other pre-alpine lakes as a consequence of atmospheric nuclear weapons testing fallout and the fallout from the nuclear accident in Chernobyl. It presents data on the ¹³⁷Cs distribution in tributaries, lake water, bottom sediments and reveals the role of ¹³⁷Cs as a marker of the sedimentation processes. The run-off of ¹³⁷Cs from the watershed to the lake is described with a simple compartment model. Measurements of the activity concentration of ¹³⁷Cs in sediments are compared with the output of a model (diffusion–convection type) which describes the input of ¹³⁷Cs into and its vertical distribution within the sediment. Varying sedimentation rates (0.05–0.90 g (cm² y)⁻¹) in Lago Maggiore are compared with data of other authors. Sedimentation rates and total distribution coefficients (of about 10⁵ L kg⁻¹) in Lago Maggiore are discussed and compared with those of Lago di Lugano, Lake Constance, and Lake Vorsee.     

Calculation and decomposition of regional household energy consumption in China: based on perspectives of urbanization and residents’ consumption

Demographic urbanization caused great changes in scale of residents’ consumption and residents’ lifestyle and then impacted changes of regional household energy consumption. This paper expanded Logarithmic Mean Decomposition Index method through introducing variables of urbanization and residential consumption into the model. It also analyzed the influences of six factors as energy structure, energy intensity, population scale, urbanization, residential consumption, and consumption inhibit on regional household energy consumption. Results showed that in 2003–2012, impact of urbanization on regional household energy consumption of Chinese three areas was significantly higher than population size. The “population gathered in eastern region” phenomenon caused eastern region getting the largest population scale effect. Driving force of residential consumption on regional household energy consumption was much higher than the other five effects. Due to the comparative advantage of residential consumption compared with government consumption, investment, and net export, the decrease of consumption ratio promoted the growth of regional household energy consumption. Energy intensity in Chinese three regions kept reducing in 2003–2012. The progress of energy utilization technology slowed the growth of regional household energy consumption, and energy intensity effect was most significant in the central region.     

The human cycle of water: water management and anthropogenic contaminant pathways in Pótam,Sonora, Mexico’s water cycle

Women are the primary decision makers regarding household water sources in many developing nations, but are often overlooked by researchers and organizations as primary water managers. This study took place in Pótam, Sonora, Mexico, during the summer of 2007, with a follow-up visit in February 2008. The study aimed at understand the human cycle of water by identifying potential exposure pathways for water contamination, as well as to understand the link between cultural beliefs, perceptions, and associated health issues. In total, sixty women were interviewed, as well as community elders and the Water Committee president. Discussions of household water use decisions, perceptions of disease causation, and treatment proved crucial in the discovery of potential pathways by which anthropogenic contaminants come into contact with the water cycle in Pótam. Most of the households (87%) believe their water sources are contaminated with biological and or chemical contaminants. Furthermore, of the sixty informants interviewed, seventy percent reported diarrhea as a common symptom. The majority of informants (76%) made a link between consumption of contaminated water and high rates of diarrhea. The study determined that the community is in need of outreach programs geared toward women as household water managers, independent lab analysis of water quality samples, and an epidemiological study to determine the causes for the most commonly reported illness and symptoms.     

Federalism,water, and (de)centralization in Brazil: the case of the São Francisco River water diversion

Regional Environmental Change - The Brazilian Northeastern semi-arid region’s history has been characterized by drought, water scarcity, and poor living conditions. For the last...     

Globalization and natural resources: the expansion of the Spanish agrifood trade and its impact on water consumption, 1965–2010

Beginning in 1960, the Spanish agricultural sector underwent an intensive process of development, resulting in important structural changes, not only in the sector itself, but also in the relationship of the agrarian system to natural resources. These changes were closely related to the growth of per capita income and Spain’s increasing integration into international markets. In the last five decades, the volume of Spanish agricultural trade has increased strongly, with a concomitant increase in the consumption of domestic water resources, requiring the construction of water infrastructure for irrigation. This paper examines the impact on water use in Spain during a period of economic modernization and trade liberalization. More specifically, we are interested in obtaining virtual water trade flow trends and identifying the major drivers responsible for these trajectories, via a decomposition analysis. Our results point to a large increase in virtual water exports and imports, primarily driven by the scale effect, that is, by the growing integration into international markets. The composition effect and changes in water intensity entailed a moderation in water consumption.     

Government drive,economic induction,and construction of food traceability systems:An empirical study based on supermarket samples from ’first-tier’ and ’Olympic’ cities in China

Food traceability systems are capable of overcoming or alleviating problems caused by incomplete and asymmetric information on food markets.This study conducts an empirical analysis using 308 supermarket samples from China’s Beijing,Guangzhou,and Qingdao to determine the factors that influence supermarket behavior when operating traceability systems.The results show that operating profits(generated from food traceability systems),scale of operation,level of economic development(of a city),and government subsidies will positively affect the decision of supermarkets to use traceability systems.At the same time,government policies promoting food traceability systems should have a long-term role.     

Patterns and changes of land use and land-use efficiency in Africa 1980–2005: an analysis based on the human appropriation of net primary production framework

Regional Environmental Change - African land systems play a decisive role in addressing future sustainability challenges for food and energy supply—in Africa and potentially elsewhere....     

Probabilistic distribution coefficients (Kds) in freshwater for radioisotopes of Ag,Am, Ba,Be, Ce,Co, Cs,I, Mn,Pu, Ra,Ru, Sb,Sr and Th – implications for uncertainty analysis of models simulating the transport of radionuclides in rivers

The objective of this study was to provide operational probability density functions (PDFs) for distribution coefficients (K_ds) in freshwater, representing the partition of radionuclides between the particulate and the dissolved phases respectively. Accordingly, the K_d variability should be considered in uncertainty analysis of transport and risk assessment models. The construction of PDFs for 8 elements (Ag, Am, Co, Cs, I, Mn, Pu and Sr) was established according to the procedure already tested in Durrieu et al. [2006. A weighted bootstrap method for the determination of probability density functions of freshwater distribution coefficients (K_ds) of Co, Cs, Sr and I radioisotopes. Chemosphere 65 (8), 1308–1320]: (i) construction of a comprehensive database where K_ds values obtained under various environments and parametric conditions were collected; (ii) scoring procedure to account for the ‘quality’ of each datapoint (according to several criteria such as the presentation of data (e.g. raw data vs mean with or without replicates), contact time, pH, solid-to-liquid ratio, expert judgement) in the construction of the PDF; (iii) weighted bootstrapping procedure to build the PDFs, in order to give more importance to the most relevant datapoints. Two types of PDFs were constructed: (i) non-conditional, usable when no knowledge about the site of concern is available; (ii) conditional PDFs corresponding to a limited range of parameters such as pH or contact time; conditional PDFs can thus be used when some parametric information is known on the site under study. For 7 other radionuclides (Ba, Be, Ce, Ra, Ru, Sb and Th), a simplified procedure was adopted because of the scarcity of data: only non-conditional PDFs were built, without incorporating a scoring procedure.     

The impact of economic,social, and political globalization and democracy on life expectancy in low-income countries: are sustainable development goals contradictory?

The 17 Sustainable Development Goals announced by the United Nations are important guides for the development processes of developing countries. However, achieving all of these goals is only possible if the goals are consistent with each other. It has been observed in the literature that possible contradictions between these goals are ignored. Therefore, the main purpose of this study is to investigate whether two sustainable development goals (SDGs) of the UN are contradictory or supporting each other in low-income countries. These SDGs are “Good Health and Well-Being” (SDG3) and “Partnerships for the Goals” (SDG17). For this purpose, the role of globalization and democracy in life expectancy is empirically investigated in 16 low-income countries over the period 1970–2017. While globalization has been used as an indicator of the partnership between countries, democracy has been used as an indicator of accountability and cooperation between governments and societies. According to estimations of the continuous-updated fully modified (CUP-FM) and bias-adjusted ordinary least squares (BA-OLS), globalization and its subcomponents such as economic, social, and political globalization affect life expectancy positively. Democracy also increases life expectancy in those countries. The GDP per capita is also used as a control variable. Our results show that a higher level of per capita income is positively associated with higher levels of life expectancy. In conclusion, no contradiction was found between SDG3 and SDG17 in those countries. Achieving a healthier society requires economic, social, and political integration between governments and societies.

     

Fishers’ perceptions of climate change,impacts on their livelihoods and adaptation strategies in environmental change hotspots: a case of Lake Wamala,Uganda

Fisheries resources support livelihoods of fishing communities but are threatened by over-exploitation, habitat degradation, pollution, invasive species and climate change. Unlike the other threats, climate change has received limited consideration and reducing its risks requires appropriate adaptation strategies. This study used quantitative and qualitative methods to generate knowledge on fishers’ perceptions of climate change, changes in climate variables and their impacts on livelihoods, adaptation strategies, constraints to adaptation and required interventions to promote adaptation strategies that would enable fishers to build resilience to sustain their livelihoods. We found that fishers were aware of changes in climate conditions manifested by unpredictable seasons, floods and droughts. Fishing remained the main livelihood activity. However, the dominance of fishes had changed from Nile tilapia (Oreochromis niloticus L.) to the African catfish (Clarias gariepinus Burchell). Floods and droughts were associated with damage to gears, boats, landing sites and changes in fish catches and sizes, income from fishing and fish consumption. The fishers adapted by increasing time on fishing grounds and changing target species and fishing gear among other things. Some innovative fishers diversified to high-value crops and livestock. This increased their income beyond what was solely earned from fishing which provided an incentive for some of them to quit fishing. Livelihood diversification was enhanced by use of communications technology, membership of social groups, increasing fishing days and fishing experience. Adaptation was, however, constrained by limited credit, awareness and access to land, which require interventions such as improving access to credit, irrigation facilities, appropriate planting materials and awareness raising. We identified adaptation strategies, which if promoted and their constraints addressed, could increase resilience of fishers to the influence of climate change and sustain their livelihoods.