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Eolian dust plays an important role in the Earth’s climate system. Environmental magnetism has been widely used to trace dust variations at different spatial and temporal scales. However, the magnetic properties of sediments from key dust sources have not been well determined. In this study, surface samples from potential dust sources in inner Eastern Asia were systematically investigated. Our results indicate that ferrimagnetic and antiferromagnetic minerals are both present in surface sediments and that they have broad grain size distributions. Ferrimagnetic components are dominated by partially oxidized coarse-grained (pseudo-single domain and multi-domain) lithogenic magnetite particles with minor contributions from pedogenic fine-grained (single domain and superparamagnetic) particles. Antiferromagnetic hematite can be classified into three groups in terms of diffuse reflectance spectroscopy (DRS) band positions ( P 560 nm , P 545 nm , and P 535 nm , where numbers indicate the DRS band wavelength for hematite). The first group ( P 560 nm ) is the coarse-grained hematite of lithogenic origin and is mostly confined to western China. The P 535 nm group is of pedogenic origin. The P 545 nm group is an intermediate phase that is present both in surface samples from the source regions and in loess. Therefore, the P 545 nm and P 535 nm groups are related to eolian inputs to the Chinese Loess Plateau and pedogenic processes, respectively. In addition, significant differences exist between the magnetic properties of eolian material from sources and depositional regions due to gravitational sorting. These insights provide strong constraints on interpretation of dust signals recorded by the Chinese loess and marine sediments from the North Pacific Ocean.

Studies of ‘food globalisation’ have traced the dispersal of cereals across prehistoric Eurasia. The degree to which these crops were accompanied by knowledge of soil and water preparation is less well known, however. The authors use stable isotope and archaeobotanical analyses to trace long-term trends in cultivation practices on the Loess Plateau (6000 BC–AD 1900). The results indicate that ancient farmers cultivated grains originating in South-west Asia and used distinct strategies for different species. Barley was integrated into pre-existing practices, while wheat was grown using novel soil and water management strategies. These distinct approaches suggest that the spread of prehistoric crops and knowledge about them varied by local context.

Preterm birth is the second largest direct cause of child deaths in children younger than 5 years. Yet, data regarding preterm birth (<37 completed weeks of gestation) are not routinely collected by UN agencies, and no systematic country estimates nor time trend analyses have been done. We report worldwide, regional, and national estimates of preterm birth rates for 184 countries in 2010 with time trends for selected countries, and provide a quantitative assessment of the uncertainty surrounding these estimates. We assessed various data sources according to prespecified inclusion criteria. National Registries (563 datapoints, 51 countries), Reproductive Health Surveys (13 datapoints, eight countries), and studies identified through systematic searches and unpublished data (162 datapoints, 40 countries) were included. 55 countries submitted additional data during WHO's country consultation process. For 13 countries with adequate quality and quantity of data, we estimated preterm birth rates using country-level loess regression for 2010. For 171 countries, two regional multilevel statistical models were developed to estimate preterm birth rates for 2010. We estimated time trends from 1990 to 2010 for 65 countries with reliable time trend data and more than 10 000 livebirths per year. We calculated uncertainty ranges for all countries. In 2010, an estimated 14·9 million babies (uncertainty range 12·3–18·1 million) were born preterm, 11·1% of all livebirths worldwide, ranging from about 5% in several European countries to 18% in some African countries. More than 60% of preterm babies were born in south Asia and sub-Saharan Africa, where 52% of the global livebirths occur. Preterm birth also affects rich countries, for example, USA has high rates and is one of the ten countries with the highest numbers of preterm births. Of the 65 countries with estimated time trends, only three (Croatia, Ecuador, and Estonia), had reduced preterm birth rates 1990–2010. The burden of preterm birth is substantial and is increasing in those regions with reliable data. Improved recording of all pregnancy outcomes and standard application of preterm definitions is important. We recommend the addition of a data-quality indicator of the per cent of all live preterm births that are under 28 weeks' gestation. Distinguishing preterm births that are spontaneous from those that are provider-initiated is important to monitor trends associated with increased caesarean sections. Rapid scale up of basic interventions could accelerate progress towards Millennium Development Goal 4 for child survival and beyond. Bill & Melinda Gates Foundation through grants to Child Health Epidemiology Reference Group (CHERG) and Save the Children's Saving Newborn Lives programme; March of Dimes; the Partnership for Maternal Newborn and Childe Health; and WHO, Department of Reproductive Health and Research.

The expansion of inland Asia deserts has considerably influenced the environmental, social and economic activities in Asia. Aridification of inland Asia, especially timing of the initiation of Asian desertification, is a contentious topic in paleoclimatology. Late Cenozoic eolian loess-red clay sequences on the Chinese Loess Plateau, which possess abundant paleoclimatic and paleo-environmental information, can be regarded as an indicator of inland Asia desertification. Here we present a detailed magnetostratigraphic investigation of a new red clay sequence about 654 m in Zhuanglang located at the western Chinese Loess Plateau. Sedimentological, geochemical, mineralogical, and quartz morphological lines of evidence show that the red clay is of eolian origin. Magnetostratigraphic correlations indicate that this core sequence spans from 25.6 to 4.8 Ma, and typical eolian red clay appears as early as 25 Ma. This extends the lower limit of the red clay on the Chinese Loess Plateau from the previously thought early Miocene back into the late Oligocene. This new red clay record further implies that the inland Asia desertification was initiated at least by the late Oligocene. This sequence provides a unique high-resolution geological record for understanding the inland Asia desertification process since the late Oligocene.

Population expansions and contractions out of and into Africa since the early Pleistocene have influenced the course of human evolution. While local- and regional-scale investigations have provided insights into the drivers of Eurasian hominin dispersals, a continental-scale and integrated study of hominin-environmental interactions across Palearctic Eurasia has been lacking. Here, we report high-resolution (up to ∼5-10 kyr sample interval) carbon isotope time series of loess deposits in Central Asia and northwest China, a region dominated by westerly winds, providing unique paleoecological and paleoclimatic records for over ~3.6 Ma. These data, combined with further syntheses of Pleistocene paleontological and archaeological records and spatio-temporal distributions of Eurasian eolian deposits and river terraces, demonstrate a pronounced transformation of landscapes around the Mid-Pleistocene Climate Transition. Increased climate amplitude and aridity fluctuations over this period led to the widespread formation of more open habitats, river terraces, and desert-loess landscapes, pushing hominins to range more widely and find solutions to increasingly challenging environments. Mid-Pleistocene climatic and ecological transitions, and the formation of modern desert and loess landscapes and river networks, emerge as critical events during the dispersal of early hominins in Palearctic Eurasia. Mid-Pleistocene climatic and ecological transitions and the formation of modern desert and loess landscapes and river networks emerge as critical events during the dispersal of early hominins in Palearctic Eurasia.

Saline loess is widely distributed in Africa, Latin America and Asia and is characterized by wet expansion and dry shrinkage, which has a large impact on the environment. In this study, the electrical resistivity of sodium sulfate loess and sodium chloride loess with moisture content (8–24%) and salt content (0.3–2.7%) was measured by an LCR digital bridge instrument. The experimental results demonstrated a decrease in the resistivity with the increase in moisture and salt content. When the salt content was greater than 0.9%, the rate of reduction in resistivity decreased and showed a tendency to be stable. With the increase in moisture content, the water conductive path changes from water in diffusion double layer (DDL) to capillary water and finally to gravity water, which in turn leads to a gradual decrease in the rate of reduction in resistivity. At the same salt content, the resistivity of sulfate loess is higher than that of chloride loess. This study analyses the resistivity changes of two kinds of salt-bearing loess under different water and salinity conditions, which has certain guiding significance for environmental monitoring and pollutant assessment based on resistivity data.

The northern mid-latitude westerlies play an important role in the climate interactions between the low and high latitudes. Our understanding of the factors that control the latitudinal displacement of the westerlies remains incomplete due to insufficient climatic proxy. Here we present a latitudinal-shift record of the westerlies in the eastern Central Asia over the past 70,000 years, on the basis of the grain size of the loess sequence from the Tacheng basin. On millennial timescale, the variation of the reconstructed westerlies resembles that of the Greenland temperature and the Atlantic meridional overturning circulation (AMOC), indicating the role of the AMOC on the westerlies. On orbital time scale, their variation is controlled by precession and insolation. Our analyses of the LOVECLIM and CCSM3 models’ results show that the impact of insolation and AMOC on the latitudinal shift of the westerlies is through changing the latitudinal temperature and pressure gradients.

The relationship between the East Asian summer monsoon (EASM) and East Asian winter monsoon (EAWM) across time scales has been an interesting topic for decades. In this study, we quantitatively investigate the EASM–EAWM relationship at the obliquity time scales using a set of accelerated transient simulations. By comparing different indices defined with different variables, we find that the EASM and EAWM intensities are positively correlated under obliquity forcing. High obliquity leads to warmer summertime and cooler wintertime surface temperatures, with a stronger response observed over land than over the oceans. The warmer summertime and cooler wintertime temperature responses are accompanied by a strengthened Asian low in summer and Siberian high in winter, with enhanced southerlies in summer and northerlies in winter, indicating an enhanced EASM and EAWM. Modulated by ice sheet forcing, however, the evolution of the simulated EAWM shifts toward the ice sheet maximum, such that the circulation-based EASM–EAWM relationship in the realistically forced simulation exhibits a phase shift of approximately 11 kyr, closer to the phase between the composite δ 18O and loess grain size in observations. Our results may have implications for better understanding the distinct changes in the proxy-based EASM–EAWM relationship before and after the rapid growth of global ice volume at around 3Ma.

Agriophyllum squarrosum (sand rice), a member of the Amaranthaceae family adapted to arid to semi-arid conditions in central Asia, produces highly nutritious seed. Three ecotypes collected from sand dunes in the western Chinese arid desert region (Linze, Minqin and Shapotou) and three from the semi-arid desert region (Duolun, Naiman, and Aerxiang) were grown in loess soil at an experimental station (Gaolan) to characterize their performance with respect to plant architecture and seed yield-associated traits. The ecotypes originating from the more arid sites developed into taller, more strongly branching plants, formed thicker stems and a greater number of spikes. Those collected from the semi-arid sites developed larger seeds and were of shorter duration. The highest seed yields were obtained from the Aerxiang ecotype (129.55 g/m 2 ). The same ecotype also exhibited both the highest emergence rate and the most favorable harvest index. The study represents the first assessment of the agronomic performance of sand rice and shows what needs to be done to domesticate and improve the species before it can be considered as a viable crop species.