‘Nation-states’, ‘quasi-states’, and ‘collapsed-states’ in contemporary Africa

The revival of ethnic identities and the search for historical roots have been significant factors in re-shaping the map of the world in the late twentieth century. Multi-ethnic states have come under increasing strain throughout the century and undermining the concept of the nation-state. However, the successor states to the colonial empires in Africa exhibit the same strains as the often highly fragile successors to the European continental empires earlier in the century. The survival of these quasi-states has been dependent upon the support of the international community for over thirty years as a reaction to the era of colonialism. Anti-colonialism offers little practical support for states in a post-colonial, post-Cold War era. In some cases the result has been disintegration and the emergence of the collapsed state. The revived political movements aimed at democratisation and self-determination have unleashed forces which may be incompatible with the survival of the current state system.     

Crystal chemistry of wadsleyite II and water in the Earth’s interior

Wadsleyite II is a variably hydrous magnesium-iron silicate phase similar to spinelloid IV and a potential host for H in the Transition Zone of the Earths mantle. Two separate samples of wadsleyite II synthesized at 17.5 GPa and 1400°C and at 18 GPa and 1350°C have been characterized by electron microprobe, single-crystal X-ray diffraction, visible, IR, Raman, and Mössbauer spectroscopies, and transmission electron microscopy including electron energy-loss spectroscopy. The two samples have the following chemical formulae: Mg_1.71Fe_0.18Al_0.01H_0.33Si_0.96O₄ and Mg_1.60Fe_0.22Al_0.01 H_0.44Si_0.97O₄. Mössbauer spectroscopy and electron energy loss spectroscopy (EELS) indicate that about half of the iron present is ferric. Refinement of the structures shows them to be essentially the same as spinelloid IV. Calculated X-ray powder diffraction patterns show only subtle differences between wadsleyite and wadsleyite II. The hydration mechanism appears to be protonation of the non-silicate oxygen (O2) and possibly the oxygens surrounding the partially vacant tetrahedral site Si2, charge-balanced by cation vacancies in Si2, M5 and M6. The unit cell volume of this phase and its synthesis conditions indicate that it may be an intermediate phase occurring between the fields of wadsleyite and ringwoodite, if sufficient trivalent cations are available. The unit cell parameters have been refined at pressures up to 10.6 GPa by single-crystal X-ray diffraction in the diamond anvil cell. The refined bulk modulus for the sample containing 2.8 wt% H₂O is 145.6 ± 2.8 GPa with a K of 6.1 ± 0.7. Similar to wadsleyite and ringwoodite, hydration has a large effect on the bulk modulus. The presence of this phase in the mantle could serve to obscure the seismic expression of the phase boundary between wadsleyite and ringwoodite near 525 km. The large apparent effect of hydration on bulk modulus is consistent with hydration having a larger effect on seismic velocities than temperature in the Transition Zone.     

‘Ageing in place’: experiences of older adults in Amsterdam and Portland

This article addresses the importance and meanings of formal and informal social support relationships and neighbourhood ties for older adults ‘ageing in place’ in urban neighbourhoods in two different welfare state settings: Portland (Oregon, the United States) and Amsterdam (the Netherlands). The rising number of people growing old(er) in urban environments raises new demands and pressing challenges for urban development. The majority of older adults are and will be ageing in their homes and communities, as opposed to institutionalized care facilities and settings. At the same time, the provision of formal and public care is being increasingly challenged by government cutbacks. On top of this, the formerly strong welfare states in many European countries have weakened. In-depth interviews with 40 older adults and key informants in two neighbourhoods in each city provide the empirical basis for this study. In Portland, there are widespread local civic initiatives related to care provision for older adults. The city has a long tradition both of individual responsibility and community culture, which has emerged from and appears to compensate for the overall lack of state services and support. Amsterdam has a long tradition of state provision, but is experiencing a policy shift towards a stronger reliance on private market-led services, and an emphasis on family and community as providers of support. Although a few emerging local initiatives for elderly care in Amsterdam were identified, it is unclear whether this form of community support can compensate for decreasing state provision in Amsterdam. This study raises concerns about the future of care provision for older adults living in unsupportive urban neighbourhoods, without financial resources or nearby relatives.     

Long-term trend analysis of water table using ‘MAKESENS’ model and sustainability of groundwater resources in drought prone Barind area,NW Bangladesh

In Bangladesh, agriculture plays a major role in the national economy. In the drought prone Barind area in NW Bangladesh, cropping intensity has increased almost double since late eighties of last century (from 1985) because of the introduction of groundwater irrigation. Long-term behavior of groundwater table (GWT) in the drought prone Barind area has been studied using MAKESENS model in the wake of massive installation of tube-wells. The study reveals that the maximum and minimum depths to GWT during 1991-2010 show on average declining trend of 4.51 m and 4.73 m. The long-term prediction for the period of 2020-50 assuming the current rate of groundwater withdrawal is that the declining trend will be 1.16 to 1.59 and 1.07 to 1.82 times more for maximum and minimum groundwater depths respectively in comparison to the present. The rigorous exploitation of groundwater for irrigation, decreasing rainfall and surface geological attributes lead towards declining trend of GWT. This will hamper the country’s food security and ultimately threaten its socio-economic sustainability. So the appropriate strategies for the management of groundwater resource on a sustainable basis should be the priority for maintaining agricultural productivity.     

Discussion of ‘Soil creep effects on ground lateral deformation and pore water pressure under embankments’

Settlement analysis of field cases is normally studied based on parameters interpreted from laboratory samples influenced by varying degrees of sample disturbance. Such disturbance is more pronounced in natural soft clays and could significantly affect the engineering properties of the soil, e.g. the over consolidation ratio (OCR) and compressibility index (C_c). Hence, it is vital to understand the role of sample quality in relation to soil characterisation for long-term settlement analyses. In this work, this is numerically illustrated by use of a simple creep model along with realistic parameter selection. This work takes its starting point on critical discussion of the work presented by Fatahi et al. (2013) and uses the opportunity to further clarify some important aspects of settlement/creep analyses in light of sample quality and parameter interpretation valid for the corresponding constitutive model.     

Assessment of changes in the area of the water conservation forest in the Qilian Mountains of China’s Gansu province, and the effects on water conservation

The Qilian Mountains water conservation forest in Gansu province is an important ecological barrier surrounding the oasis in China’s Hexi Corridor. The water they provide is the basis for the existence and sustainable socioeconomic development of those oases. As a result of unsustainable use of the water conservation forest until the 1980s, the oasis ecosystems of the Hexi region were seriously damaged, and the oasis areas experienced deterioration of their ecological environment. In this paper, Landsat images were used to monitor the temporal and spatial changes in area of water conservation in Qilian Mountains of China’s Gansu province and to assess the effect on water conservation by analyzed relationship between water conservation forest area, climatic data and hydrological data. The results showed that the forest covered 15.1% of the study area in 2007 and has followed different trends during the study period. From 1978 to 1990, the forest area decreased; however, from 1990 to 2007, the forest area increased, with a faster rate of increase from 1990 to 2000, and the rate of increase averaged 2,733.89 ha per year since 1990. The water conservation forest appears to play an important role in flood control, runoff regulation, the prevention of soil erosion, and water conservation; and these benefits increase with an increasing area of forest.     

Becoming a young migrant or stayer seen through the lens of ‘householding’: Households ‘in flux’ and the intersection of relations of gender and seniority

This paper conceptualises migration and staying by young rural Lao in the empirical context of above replacement level fertility as manifestations of ‘householding’ that interacts with other dimensions of householding. Drawing on the framework of the inter-generational contract and by juxtaposing qualitative and quantitative data I show that becoming a young migrant and becoming or remaining a young stayer is shaped by young migrants’ situated agency.The second part of the paper departs from conventional household-based analyses and introduces the notion of ‘households in flux’. This highlights the dynamic interaction between changing external dynamics affecting rural households, and internal dynamics that constantly reconfigure the field of the household. These conceptual readjustments require going beyond inflexible notions of the household, the analytical disconnection between a focus on migrants and stayers in migration research, and static readings of relations of gender and generation. Furthermore, the paper argues that intra-household relations need to be appreciated as gendered relations of relative seniority which are in the process of householding constantly made and remade, among other things, by young dependents through ‘staying’ and ‘leaving’. These conceptual moves help explain the empirical puzzle of why in rural Lao households young women are both the ones most inclined to become a young migrant as well as most inclined to become or remain a young stayer.     

Sobol’ sensitivity analysis of parameters in the common land model for simulation of water and energy fluxes

The water and energy transfer of land surface is complex due to its large spatial and temporal variability. The modeling and simulation is an important means to study land water and energy transfer, but most selection and analysis of model parameters are empirical and qualitative. This paper has proposed a method of quantitatively identifying the most influential parameters of Common Land Model through Sobol?? sensitivity analysis. Considering sensible heat flux as the model output, the first order and total sensitivity indices of 25 model input parameters are estimated using an improved Sobol?? method. The simulated results are resampled using a bootstrapping method and the corresponding sensitivity indices are calculated. Confidence intervals for the bootstrapping sensitivity indices are estimated by using a percentile method. The results show that the parameters phi0 and porsl are the most important parameters, followed by ref(2,1), tran(2,1) and bsw. Five out of 25 parameters need to have an accurate evaluation, while the other parameters are fixed to a certain value. The sensitivity indices of parameters phi0 and porsl are decreasing after precipitation, while the sensitivity indices of parameters tran(2, 1) and ref(2, 1) are increasing after precipitation.     

Geochemical characteristics and source analysis of inflow of mine water in Wang’ershan Gold Mine, Shandong

Through a systematic observation of water level and temperature, and a comprehensive analysis of the data on major/trace elements, nitrite, hydrogen-oxygen isotopes, the conclusion has been drawn that there are two relatively independent groundwater systems (cool water and hot water), and the geochemical indicators of hot/cool waters are described. The cool water system is relatively enriched in Ca2 , Mg2 and HCO3-. Its TDS is relatively low, about 1400–1800 mg/L. The hot water system is relatively enriched in K , Na , Cl- and SO42-. Its TDS is relatively high, about 2200–2300 mg/L. The cool water system is enriched in Ba, Ga, Cd, and the hot water system is enriched in B, Ti, Cr, Ni, Cu, Mo, Rb, and Cs, relatively. Especially, the contents of Rb and Cs in the hot water system are more than five times as high as those in the cool water system. The NO3- contents of cool water discharged from the gold mine are relatively high, and those of hot water are extremely low. The δD and δ18O values follow an increasing order of surface water>mine cool water>mine hot water. The cool water comes mainly from the lateral supply of phreatic water, while the hot water comes mainly from the vertical supply of deeply circulating structure-fracture water. The ratio of cool water over hot water was estimated to be about 1:1 by a water quality model..     

Carbonate equilibrium in the water of the Razdol’naya River

The paper suggests an accurate approach to studying carbonate equilibrium in the water of the Razdol’naya River. The approach involves measuring pH by Pitzer’s scale, using a cell without liquid junction; measuring the total alkalinity by Bruevich’s technique; and using apparent constants of carbonate equilibrium with regard for the organic alkalinity. The Pitzer technique was employed to calculate the apparent constants of carbonate equilibrium in solution that models the riverine water: Ca(HCO₃)₂–NaCl–H₂O within the range of alkalinity of 0–0.005 mol/kg and temperatures of 0–25°C. Carbonate equilibrium in the water of the Razdol’naya River was sampled for studying at eight sites during all four seasons. Although the contents of biogenic compounds in the water are high, they can merely insignificantly affect the acid–base equilibrium, which is controlled in the riverine water by carbonate equilibrium and the concentrations of humic substances, which play the greater role, the greater the discharge of the river. In addition to the production and destruction of organic matter, carbonate equilibrium in the river is also affected by the supply of humic substances with soil waters and total alkalinity with groundwaters. The fluxes of alkalinity and humic substances annually brought by the Razdol’naya River to Amur Bay are evaluated at 1.33 × 10⁹ mol and 9.9 × 10⁶ kgC, respectively. The carbon dioxide export with the Razdol’naya River is equal to the alkalinity flux and does not depend on the weathering mechanisms.     

Characteristics of isotope in precipitation,river water and lake water in the Manasarovar basin of Qinghai–Tibet Plateau

The stable hydrogen and oxygen of lake, river, rain and snow waters were investigated to understand the water cycle characteristics of the drainage basin of Manasarovar Lake in Tibet. Both δD and δ ¹⁸O of river water are larger than those of lake water and the effect of altitude on both δD and δ ¹⁸O is not very significant. This phenomenon was suggested to occur because Manasarovar basin is located in Qinghai–Tibet Plateau which has low latitude, high altitude, abundant glaciers, thin air and intensive solar radiation, resulting in higher evaporation in lake water.     

Groundwater recharge and evolution of water quality in China’s Jilantai Basin based on hydrogeochemical and isotopic evidence

We investigated major ions, stable isotopes, and radiocarbon dates in a Quaternary aquifer in semi-arid northwestern China to gain insights into groundwater recharge and evolution. Most deep and shallow groundwater in the Helan Mountains was fresh, with total dissolved solids <1,000 mg L^?1 and Cl^? <250 mg L^?1. The relationships of major ions with Cl^? suggest strong dissolution of evaporites. However, dissolution of carbonates, albite weathering, and ion exchange are also the major groundwater process in Jilantai basin. The shallow desert groundwater is enriched in δ¹⁸O and intercepts the local meteoric water line at δ¹⁸O = ?13.4 ‰, indicating that direct infiltration is a minor recharge source. The isotope compositions in intermediate confined aquifers resemble those of shallow unconfined groundwater, revealing that upward recharge from intermediate formations is a major source of shallow groundwater in the plains and desert. The estimated residence time of 10.0 kyr at one desert site, indicating that some replenishment of desert aquifers occurred in the late Pleistocene and early Holocene with a wetter and colder climate than at present.     

Conservation and development 2.0: Intensifications and disjunctures in the politics of online ‘do-good’ platforms

An increasing amount of interactive ‘2.0’ crowdsourcing platforms raise awareness and funds for conservation and development projects worldwide. By enabling two-way online collaboration and communication, these ‘conservation and development 2.0’ platforms hoped to provide new impetus and popular legitimacy for conservation and development initiatives in the face of budget cuts and general criticism of the ‘formal’ aid sector after the financial crisis. This paper presents the case of the flagship ‘elephant corridor’ project on the Dutch pifworld.com platform to investigate whether and how the ‘2.0’ element has changed conservation and development in line with these expectations. The paper describes and analyses online and offline dynamics of the project and shows that while online excitement about the project remained high, the concomitant conservation and development promises and imaginations ill related to offline local realities. This rather ‘traditional’ conservation and development disjuncture, however, needs to be understood against the system peculiarities of the politics of online ‘do-good’ 2.0 platforms. The paper concludes that as these peculiarities are significantly intensifying and changing conservation and development dynamics, they do not elude familiar (1.0) disjunctures and might even obscure these further from sight.     

Measurement of pesticides in surface water and sediment of Caspian Sea, Iran

Background: With development of intensive agriculture in the agricultural regions of the Northern provinces (Caspian Sea coasts), which involves frequent pesticide use in highly mechanized cash-crop cultures. To investigate and provide information on pest…     

Catalytic ozonation of phenol in water with natural brucite and magnesia

Catalytic ozonation has attracted much attention in treatment of wastewater for its mild conditions. Phenol and its ramifications are common components in a wide variety of wastewaters including those from coal conversion processes, coking plants, petroleum refineries and several chemical industries. In this paper, natural brucite and magnesia have been successfully used in catalytic ozonation of phenol. And the mechanisms of catalysis were also investigated. From Figs. 1 and 2, it can be found that both brucite and magnesia have remarkable catalysis on degradation of phenol and removal of Chemical Oxygen Demand （COD）. The pH of solutions on the process of ozonation alone, catalytic ozonation with brucites and with magnesia were 6.35-2.76, 10.18-8.52 and 10.58-10.83, respectively. It can be concluded that alkali environment plays a critical role for catalytic ozonation of phenol. We also found that the alkaline minerals reacted on the surface with oxalic acid and other low molecular-weight acids which are intermediate products in ozonation, but those intermediate products could be mineralized into carbon dioxide completely with enough ozonation time.