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This study concerns the distribution and potential sources of elevated heavy metal concentrations (Cr, Ni, Pb, Zn) in alluvial sediments of the Yellow River close to an industrial area in northwest China. Sediment samples were collected from 25 locations and analyzed for common ions (Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl⁻, SO₄²⁻, HCO₃⁻), total salts, and heavy metals (Cr, Ni, Pb, Zn). Concentrations of Cr, Ni, Pb, and Zn were found to exceed background values observed at up-gradient sites and in surrounding non-industrialized areas. The surficial sediments can be classified as “slightly polluted” and seem to present a low, albeit significant potential ecological risk in the center of the study area where elevated Cr, Ni, Pb, and Zn appear to be associated with the presence of several industrial plants and a wastewater drainage ditch. Correlation and multivariate analyses confirm that the heavy metal pollution is anthropogenic in origin. Urgent action is required at both administrative and technical levels to avoid further degradation of the sediments by industrial waste. Necessary measures include the establishment of soil, sediment and water monitoring programs, a strengthening of compliance standards and greater enforcement of regulations.

Central Asia is well known for its history of water mismanagement. The rapid, catastrophic demise of the Aral Sea is testament to the unsustainable water diversion practices introduced by the Soviet Union in the 1960s and the failure of the five sovereign nations, Kazakhstan, Kyrgyzstan, Uzbekistan, Tajikistan and Turkmenistan, that inherited responsibility for Central Asia’s ailing resources, to develop the types of program necessary for the sustainable management of what had become a shared “transboundary” water resource. Although nearly 25 years have passed since the break-up of the Soviet Union, rivalry and deep mistrust between the guardian nations of Central Asia’s water resources remains a serious impediment to achieving the level of cooperation necessary for constructive, water management and decision-making. This is a grave concern given the anticipated impacts of climate change and natural population growth on water in the region. For many Asians, the recently proposed new “Silk Road Economic Belt” is viewed as an immense opportunity to bring wealth and prosperity to some of the poorest regions of China and Central Asia. However, given Central Asia’s appalling record of water management, there is little confidence that the project’s water needs can be adequately met. In effect, the new “Silk Road Economic Belt” and the rapid growth it will bring to the region, represents a serious long-term threat to the sustainable management of Central Asia’s transboundary water resources. The fundamental concern is that the project may place too great a burden on a water management system in Central Asia that is seriously dysfunctional and shows no sign of improvement. Central Asian countries need to recognise that the economic success of the “Silk Road Economic Belt” hinges on their ability to develop programs that can ensure the region’s water resources are managed in a sound and sustainable manner. This will be a difficult challenge and will require cooperation amongst the countries of Central Asia that goes far beyond what currently seems possible. Major reforms are necessary and external pressures from neighbouring Russia and China are likely required to make this happen. It is also essential that the project be supported by sound science and good hydrological data, both of which are seriously lacking in the region. There will be a need to invest in scientific research in the relevant fields. With judicious planning, good science and a commitment amongst the nations of Central Asia to create a shared vision and collaborate towards a common goal, the “New Silk Road” can be developed both beneficially and sustainably.

With over half the world’s population now living in towns and cities, serious questions are being asked about the sustainability of urban water supplies. Groundwater is a particular concern as it represents over 95 % of the world’s available fresh water reserves and supplies over 1.5 billion city dwellers with water essential for their drinking and sanitation needs. Within 20 years, the global population is projected to rise from 7 billion to 8 billion with this entire growth accommodated in urban areas. Much of the additional water required will be sought from groundwater due to the generally modest cost of waterwells and the close, “well’s length” proximity of the resource. Fortunately, significant progress has been made in the science of urban groundwater during the past 25 years, most notably with respect to the nature of urban recharge and components of the urban water balance, contaminant source characterisation, recharge management and methods of assessing aquifer vulnerability. There have also been major advances in the development and use of advanced ground and surface water modelling tools, some of which are linked with GIS and urban databanks to provide unprecedented support for resource management decision making. What is missing are appropriate systems of urban water governance that are essential for effective and responsible groundwater resource management. Despite the growing popularity of “integrated water resource management” models that promote urban water management in a comprehensive, holistic, way, it is not clear that such techniques adequately incorporate the unique storage and flow attributes of groundwater, behaviours that merit special management considerations. Today, a significantly increased awareness for the valuable role of groundwater in the urban water cycle is beginning to raise its profile at the political level. Improved groundwater governance with the full involvement of all stakeholders in the decision-making process is now recognised as the key to resolve sustainability concerns over water in the world’s rapidly growing cities.

Heavy metal pollution of sediments is a global concern and can be a serious problem in heavily industrialized parts of the world. Pollution by manganese is particularly common due to its ubiquitous natural occurrence, ease of mobilization, and extensive association with industry. In Ningxia, China, manganese pollution of Yellow River alluvial sediments was assessed by comparing manganese concentrations in 35 sediment samples with background values derived from similar sediments obtained at sites considered remote from potential sources of contamination. Natural background values of manganese were found to range from 192 to 323 mg/kg for surface sediments, and from 220 to 325 and 283 to 394 mg/kg for subsurface sediments at depths of 45–50 and 95–100 cm, respectively. In the study area, manganese content ranged from 565 to 1,363 mg/kg, indicating anthropogenic pollution extending to a depth of at least 1 m in the study area. All 35 samples were found to exceed the threshold effect concentration (TEC) of 460 mg/kg, below which adverse effects on sediment-dwelling organisms are not expected to occur, and one sample (T12) was found to exceed the probable effect concentration (PEC) of 1,100 mg/kg. PEC defines the threshold above which adverse effects are likely to be observed. Variogram analysis of the surface sediment manganese data revealed adherence to a Gaussian model, and ordinary kriging was used to generate a manganese distribution map. Analysis of the high nugget effect ratio indicates high, small-scale variations that are consistent with potential emissions from an adjacent electrolytic manganese plant.

Groundwater vulnerability assessments provide a measure of the sensitivity of groundwater quality to an imposed contaminant load and are globally recognized as an essential element of all aquifer management and protection plans. In this paper, the vulnerability of groundwaters underlying the Yinchuan Plain of Northwest China is determined using OREADIC, a GIS-based assessment tool that incorporates the key characteristics of the universally popular DRASTIC approach to vulnerability assessment but has been modified to consider important additional hydrogeological factors that are specific to the region. The results show that areas of high vulnerability are distributed mainly around Qingtongxia City, Wuzhong City, Lingwu City, and Yongning County and are associated with high rates of aquifer recharge, shallow depths to the water table, and highly permeable aquifer materials. The presence of elevated NO 3 − in the high vulnerability areas endorses the OREADIC approach. The vulnerability maps developed in this study have become valuable tools for environmental planning in the region and will be used for predictive management of the groundwater resource.

Throughout China, both coal and water are very important resources; however, serious conflict can arise between mining of deep coal reserves and essential aquifer resources. The problem is particularly severe in eastern China where a deep, thick, and productive Ordovician limestone aquifer immediately underlies Permo-Carboniferous coal-bearing sediments and poses a serious threat to the safety of coal exploitation. The problems are caused by high water pressures in the Ordovician aquifer and the risk of catastrophic flooding at the coalface caused by strong upward flow across a relatively thin aquitard. The problem can be alleviated by mine dewatering, but this generates large volumes of contaminated wastewater that require safe disposal. In a feasibility study carried out at Yanzhou coalfield, eastern China, hydrogeological studies have been undertaken to explore options for utilizing water pumped during mining operations, thus making more efficient use of the Ordovician groundwater reserves. The groundwaters are recharged at outcrops but readily become SO4·Cl–Ca·Mg in character with TDS increasing considerably with depth. Focusing on the Xinglongzhuang coal mine, test pumping and development of a transient groundwater flow model of the system have allowed alternative strategies for pressure management to be investigated. The study shows that coal-mining operations can proceed safely with as few as six underground dewatering boreholes removing 1800 m3/h. Moreover, the extracted water could be utilized after treatment to reduce sulfate concentrations. The coordinated exploitation approach demonstrated in this study provides a good example of wise environmental stewardship that other extractive industries would do well to consider.

The building of the Silk Road economic belt is an exciting prospect that may bring immense economic benefits to Eurasian countries. However, intensive human activities to be induced by it may double the water crisis in central Asia, deteriorate the vulnerable environment, and accelerate energy consumption in this area. To build a new and sustainable Silk Road economic belt, advancing scientific research, reinforcing international collaboration and enhancing education are necessary steps. With careful planning, sound research, good data and the support from governments and the people, the Silk Road economic belt can be developed in an environmentally sustainable manner that is a credit to all involved.

Ground fissures in China have garnered increasing international attention in recent years due to their areal extensiveness, large scale, and high hazard potential. These fissures, especially those in the Fen-Wei Basin and North China Plain, severely restrict planning and construction in big cities, threaten the operation of underground and above ground railways, and cause serious economic loss. Recent research shows that ground fissures in China occur mainly in sedimentary basins and develop along active faults and at the edges of groundwater cones of depression. Most of these fissures are caused by the combined action of tectonic stress and hydrodynamic force. Effective ground fissure disaster reduction technologies are developed and they include pumping control, reasonable avoidance, adaption to deformation, and local strengthening. This paper provides an overview on ground fissure studies in China and demonstrates how research results can serve economic development and geohazard mitigation.