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Scientifically validating the value of rural heritage and exploring construction wisdom has emerged as a significant challenge in the study of rural settlements worldwide. Rural heritage shows significant differences according to the natural environment, history, culture, and socio-economic factors. However, the assessment of the authenticity and effectiveness of heritage values have yet to be quantified due to the difficulty in obtaining evidence directly from samples. By constructing a multi-dimensional model of villages for quantitative analysis, we proposed a multifaceted spatial visibility analysis method based on individual and combined defense structures to empirically study the remains of eight towers in Moluo village, western China. This study demonstrated that towers serve as regional defense structures and are essential for constructing a comprehensive and effective visual defensive system (VDS) in Moluo village, a typical military defense village. The effectiveness and coverage of the towers vary depending on their location, height, type, and other factors. They form a complementary and synergistic relationship, playing a dual mechanism of public and private, local and overall defense. In summary, this method enables the feasible quantification and analysis of the functional value of rural heritage through landscape visual analysis. It provides a new perspective for studying the authenticity of heritage functions. [ABSTRACT FROM AUTHOR]

Tropical cyclone (TC) translation distance, proportional to its duration and translation speed, basically determines the spatial extent of TC-impacted marine and terrestrial areas. Although a long-term slowdown of TCs has recently been reported, changes in translation distance of TCs over the western North Pacific (WNP) and their driving mechanisms remain poorly understood. Using multiple TC datasets, here we find that the trends are opposite in overland translation distance of landfall WNP TCs over China and excluding China, with the number of landfalls in the two groups being almost the same. However, the increase in overland translation distance of landfall TCs over China is offset by a greater decrease in that excluding China, with the result that the overland translation distance of TCs over the WNP has declined (−4.0% decade−1). The oversea translation distance of TCs over the WNP also shows a decreasing trend (−2.4% decade−1), and thus the genesis-to-demise translation distance of TCs over the WNP has significantly decreased (by 17.7%) during 1961–2019. The shorter duration and reduced translation speed of TCs directly and jointly contribute (by 76.9% and 23.1%, respectively) to their shortened translation distance. The gradual increase in westerly and northerly winds and weaker moisture transport during the days following TC generation tend to inhibit long-distance travel after TC genesis. Declining TC translation distance is likely associated with the long-term increases in genesis potential index and an anomalous cyclonic steering flow over the WNP. Our findings suggest that these changes in TC translation distance may alter regional patterns of TC-related drying and wetting of the WNP. Significance Statement: The spatial extent affected by a tropical cyclone (TC) is largely determined by TC translation distance. For example, TCs passing through marine areas could cool sea surface temperature and modulate local air–sea heat fluxes exchange; TCs with longer translation distances over land are more likely to trigger widespread flooding or terminate droughts in inland areas. Over the western North Pacific (WNP), we find that observational evidence supports opposite trends in overland translation distance of landfall TCs over China and excluding China. Nevertheless, the genesis-to-demise translation distance of TCs shows a significant decline over the WNP during the past six decades. Understanding the impacts of changes in TC translation distance has particular importance given the extensive footprint of TC-related drying and wetting of the marine and terrestrial areas. [ABSTRACT FROM AUTHOR]

The aim of this work is to reveal impacts of a nuclear power plant on environmental radioactivity and public health since commission in the South China Sea. After long-term monitoring, it turns out that radioactivity in ambient air environment, water, soil, sweet potato, rice, chicken, lamb, butterfish and prawn meet demands of national environment protection standards and food safety standards in China. After 6 years' statistic check of local residents, the top tree diseases before and after the plant's commission remained pulmonary tuberculosis, hand-foot-and-mouth disease, and hepatitis B. Incidence of malignant tumor did not rise. [ABSTRACT FROM AUTHOR]

Graphical abstract Potash deposits are common in the Mesozoic-Cenozoic Tethyan domain, which features the giant potash deposits in the Late Jurassic Central Asian Basin and the Late Cretaceous Khorat Basin of Thailand-Laos. Widespread evaporitic sequences from this interval have been found in some marine and transitional basins within the Chinese continental blocks, such as the Yangtze, Simao and Tarim Blocks, in which, only one small-scale potash deposit had been found in the Late Cretaceous Simao Basin. These evaporites are commonly characterized by depositional cycles that are more frequent than those of other potash basins around the world. It remains debated whether large or giant potash deposits could be formed in Chinese blocks of Tethyan domain, and if so, what mechanism was responsible for the potash formation. To address these issues, we comprehensively review the Meso-Cenozoic drift history and collision dynamics of these Chinese blocks and summarize the formation mechanism, depositional characteristics, and paleoclimate of the evaporite basins in these blocks. These blocks drifted from the Southern Hemisphere and collided and welded together beginning in the late Permian in the Northern Hemisphere. The collisions often commenced in the east and gradually spread to the west of these blocks, resulting in: (1) westward seawater retreat; (2) differential topographic uplift with high topography in the east and low topography in the west and (3) increasingly closed depositional environments in these basins. In addition, these collisions often exerted nearly N-S-oriented principal compressive stress, which resulted in nearly E-W-oriented extension. These forces induced a series of faulted-bounded subsidence belts with N-S-striking extensional sub-basins arranged in an E-W-oriented chain in these blocks. In this chain-like sub-basins system, as sea level rose and seawater flowed from west to east, the western sub-basins acted as evaporative preparatory basins for the eastern basins. As a result, the more eastern sub-basins contained increasingly denser brines, and ultimately potash minerals were commonly deposited in the easternmost sub-basins. Based on the above model of potash formation, we predict that potash deposits may be formed in certain sub-basins in the eastern part of these basins in Chinese Tethyan blocks, which maybe lay a theoretical foundation for China's future exploration of potash deposits. Highlights • Chinese blocks had been in the N subtropical high pressure belt since Triassic. • The cycles showing quite frequent changes of depositional environments. • The collisions of these blocks led to the westward regression of seawater. • Tectonic movements caused the unified lake transformed into sub-basins. • Potash deposits may be formed in the eastern sub-basins on these blocks. Abstract Potash deposits are common in the Mesozoic-Cenozoic Tethyan domain, which features the giant potash deposits in the Late Jurassic Central Asian Basin and the Late Cretaceous Khorat Basin of Thailand-Laos. Widespread evaporitic sequences from these intervals have been found in some marine and transitional basins within the Chinese continental blocks, such as the Yangtze, Simao and Tarim blocks, in which, only one small-scale potash deposit had been found in the Late Cretaceous Simao Basin. These evaporites are commonly characterized by depositional cycles that are more frequent than those of other potash basins around the world. It remains debated whether large or giant potash deposits could be formed in Chinese blocks of Tethyan domain, and if so, what mechanism was responsible for the potash formation. To address these issues, we comprehensively review the Meso-Cenozoic drift history and collision dynamics of these Chinese blocks and summarize the formation mechanism, depositional characteristics, and paleoclimate of the evaporite basins in these blocks. These blocks drifted from the Southern Hemisphere and collided and welded together in the beginning of the late Permian in the Northern Hemisphere. The collisions often commenced in the east and gradually spread to the west of these blocks, resulting in: (1) westward seawater retreat; (2) differential topographic uplift with high topography in the east and low topography in the west and (3) increasingly closed depositional environments in these basins. In addition, these collisions often exerted nearly N-S-oriented principal compressive stress, which resulted in nearly E-W-oriented extension. These forces induced a series of faulted-bounded subsidence belts with N-S-striking extensional sub-basins arranged in an E-W-oriented chain in these blocks. In this chain-like sub-basins system, as sea level rose and seawater flowed from west to east, the western sub-basins proximal to the open sea would have precipitated calcium carbonates and calcium sulfates, resulting in a high degree of concentration by the time the brines reached the distal end, i.e. eastern sub-basins. Ultimately, potash minerals were commonly deposited in the easternmost sub-basins. Based on the above model of potash formation, we predict that potash deposits may be formed in certain sub-basins in the eastern part of these basins in Chinese Tethyan blocks, which maybe lay a theoretical foundation for China's future exploration of potash deposits. [ABSTRACT FROM AUTHOR]

[Display omitted] • Age of the Mengyejing potash deposit is mid-Cretaceous time. • Most Cretaceous detrital zircons were mostly derived from volcano eruptions. • The Mengyejing have deposited earlier than the Khorat potash deposit by 20–25 Ma. The age of the Mengyejing potash deposit (MPD) in the Simao Basin, the only pre-Quaternary economically exploitable solid potash occurrence in China, has been the subject of debate for decades. It has been established that the ore-hosting Mengyejing Formation formed during the mid-Cretaceous based on radioactive and magnetic dating. The age discrepancy between the primary mid-Cretaceous and the squeezing of the Middle Jurassic is related to the lack of direct previous dating of the MPD itself. In this study, detrital zircon U-Pb dating of four clastic rock samples interbedded with the potash layers yielded the youngest zircon ages of 104.8, 106.5, 107.8, and 110 Ma. Taking into account the relatively large proportion of the youngest Cretaceous zircons and the Hf isotopic analysis, we propose that most of the Cretaceous zircons were derived from the contemporaneous volcanic activity that produced the tuff beds within the potash deposit and elsewhere in the Mengyejing Formation, while only a small fraction of the Cretaceous zircons were found to be of detrital origin and have derived from the Bomi-Chayu and Dianxi-Burma batholiths. Consequently, the maximum age of the potash deposit of 110 to 105 Ma is the true depositional age of the strata and potash deposit. [ABSTRACT FROM AUTHOR]

Evaporites are widely distributed within continental "red beds" in the Lanping–Simao Basin, west Yunnan, China. Sr (Strontium), S (Sulfur), and O (Oxygen) isotope compositions have been measured on 54 sulfate or/and sulfate-bearing samples collected from Lanping, Nuodeng, Jinggu, Mengyejing, Baozang throughout the Lanping–Simao Basin. The 87Sr/86Sr ratios of all samples (0.708081 to 0.710049) are higher than those of contemporaneous seawater, indicating a significant continental contribution to the drainage basin. Sulfates in the Lanping Basin have higher 87Sr/86Sr ratios (0.709406 to 0.710049) than those (0.708081 to 0.709548) in the Simao Basin. Nevertheless, the δ34S values of gypsums (13.4‰ to 17.6‰) in Lanping and Baozang fall within the range of Cretaceous seawater. Gypsums from a single section in Baozang have trends of decreasing δ34S values and increasing 87Sr/86Sr ratios from base to top, indicating continental input played an increasingly significant role with the evaporation of brines. High δ34S values (20.5‰ to 20.7‰) of celestites in Lanping are probably caused by bacterial sulfate reduction (BSR) process in which 34S were enriched in residual sulfates and/or recycling of Triassic evaporites. The reduced δ34S values of gypsums (9.5‰ to 10.4‰) in Nuodeng could have been caused by oxidation of sulfides weathered from Jinding Pb-Zn deposit. The complex O isotope compositions indicate that sulfates in the Lanping–Simao Basin had undergone sulfate reduction, re-oxidation, reservoir effects, etc. In conclusion, the formation of continental evaporites was likely derived from seawater due to marine transgression during the Cretaceous period. Meanwhile, non-marine inflows have contributed to the basin significantly. [ABSTRACT FROM AUTHOR]

Coal will continue to be the main energy source in China for the immediate future, although the environmental pollution and ecological impacts of each stage in the full life cycle of coal mining, transportation, and combustion generate large quantities of external costs. The Late Permian coals in southwestern (SW) China usually contain high amounts of fluorine (F), arsenic (As), and ash, which together with high-F clays cause abnormally high levels of endemic fluorosis, As poisoning, and lung cancer in areas where coal is mined and burned. In this paper, we estimate the external costs of the life cycle of coal. The results show that the externalities of coal in SW China are estimated at USD 73.5 billion or 284.3 USD/t, which would have accounted for 6.5 % of the provincial GDP in this area in 2018. The external cost of human health accounts for 87.2% of the total external costs, of which endemic skeletal fluorosis diseases and related lung cancers have the most important impact. Our study provides a more precise estimate of externalities compared with its counterparts in other provinces in China. Therefore, several policy recommendations would be proposed to internalize the external cost. [ABSTRACT FROM AUTHOR]

Many soil and water conservation measures (SWCM) have been implemented in the Loess Plateau of China, and they have an impact on ecosystems all levels and involve complicated mechanisms. Previously, studies typically focused on a single factor's effect on diversity or productivity. With this background, the current investigation embarked on an extensive study, with vegetation survey conducted in the no measure plots (NM), vegetation measure plots (VM) and engineering measure plots (EM) in the Loess Plateau of China. We used structural equation models (SEM) to explain the mechanism by which SWCM affects plant productivity and diversity. VM have direct effects on plant diversity, and EM have direct effects on soil properties and community structure. The two measures also had indirect effects on plant functional traits and community structure. The results show that the changes in plant functional traits and community structure by SWCM decreased plant diversity, whereas the increase of productivity was primarily dominated by improvements in community structure, and we conclude that variability in plant diversity and productivity across different measures on the Loess Plateau was primarily due to the responses of different plants to variable soil properties and the community responses. It was also emphasized that vegetation measures were beneficial to the increase of biomass per plant, while engineering measures were more beneficial to the growth of dominant species. These findings provide a theoretical foundation for vegetation management and restoration after the application of different SWCM. [Display omitted] • SWCM has a direct effect on plant productivity. • SWCM indirectly affect functional traits and community structure. • All SWCM have reduced plant diversity and increased productivity. • Vegetation Measures were beneficial to the increase of biomass per plant. • Engineering Measures were more suitable for the growth of dominant species. [ABSTRACT FROM AUTHOR]

The article discusses the proposed model for marine potash deposits formed in the small continental blocks of China. Topics include the importance of extremely arid events for the brine to evaporate quickly and to precipitate potash minerals in a short time, the separation and formation of sub-basins due to tectonic movements, and the development of marine-related potash deposits in marine basins of small continental blocks through the coupling of climate events and tectonic separation.

Two types of potash ores were sampled from the Mengyejing potash deposit (the MPD) which is the only ancient potash deposit ever found in China. Geochemical analyses, including Br, K, Mg and some heavy metals, were performed on those samples. The relatively consistent Br contents (141.42 to 763.67 ppm) in both bedded potash and veined potash ores show that the potash-forming brine was likely derived from seawater. K contents and Br/Cl ratios of the veined potash ores are relatively high in contrast to bedded potash ores. The K/Br ratios of veined potash ores exhibit a positive correlation with Br contents, which is opposite to that of the bedded potash ore of the MPD and potassium-salts from the evaporation of modern seawater. The contents of heavy metals in veined potash ores are much higher than those of bedded potash ores in the MPD and potash in other evaporite basins of the world. Sr and S isotopic compositions of these two types of potash ores suggest that the brines for precipitating veined potash were formed by mixing of connate waters (seawater or/and continental freshwater) and hydrothermal fluids. The geochemical and petrological characteristics of the veined potash ores indicate that the brine for forming veined potash orebodies caused by dissolution of previous bedded potash orebodies by hydrothermal fluids. The veined potash orebodies were formed through a cooling process by which sylvite precipitated first prior to halite. [ABSTRACT FROM AUTHOR]

Paleoclimatic indicators suggest that the mid-Cretaceous was one of the warmest intervals of the Phanerozoic. The period of the mid-Cretaceous “super-greenhouse” also experienced an equator-to-pole temperature gradient much lower than that of the present day, implying greater meridional heat transport by the atmosphere and/or oceans. However, reconstructions of Cretaceous atmospheric circulation have been hindered by a lack of relevant datasets based on reliable proxies or direct geological evidence. Aeolian deposits provide direct information about paleoclimate, as well as the direction and intensity of paleo-wind in the interiors of continents. Using petrologic and sedimentologic observations, this study reassesses the terrestrial deposits of the mid-Cretaceous Mangang Formation in the Simao Basin of southwestern China. Originally considered to be aqueous deposits, we reinterpret these strata as representing aeolian transport in a desert environment. We suggest that the development of aeolian deposits in the Mangang Formation (and coeval strata in adjacent basins) was a local response to the prevailing desert climate in the mid- to low-latitudes of the Northern Hemisphere during the mid-Cretaceous, which were dominated by subtropical high-pressure systems on a planetary scale. In addition, with the closure of the Mesotethys Ocean, the intermontane basins of the South China, Simao, and Indochina blocks became more isolated from atmospheric circulation. Bidirectional subduction of the Bangong-Nujiang oceanic crust and the Izanagi Plate beneath East Asia led to the development of Andean-type margins, which created a rain-shadow effect in continental East Asia. These factors caused the development of a tropical desert climate, characterized by aeolian dunes and evaporite deposition. We speculate that the severe depletion of groundwater reservoirs via the desertification of East Asia may represent a previously unrecognized trigger for short-term sea-level changes during the ice-free Cretaceous greenhouse interval. [ABSTRACT FROM AUTHOR]

The Shulu Sag is a typical rift valley basin in Eastern China, where the formation mechanism of Cenozoic salt-bearing series has been poorly understood. In this paper, petrologic analysis, X-ray powder Diffraction (XRD) analysis and the analysis of halite ion concentrations of the first member of the Shahejie Formation from two drilling cores were conducted to interpret the formation mechanism of these salt-bearing series in Shulu Sag. The results indicated that the salt-bearing series is mainly composed of calcilutite or mudstone at top and bottom, and anhydrite-bearing halite and thin interbeds of salt-bearing calcilutite and dark grey shale in the middle part. These thin interbeds with porphyritic or petalshaped glauberite crystals or some thinner dark grey shale interbeds separated halites into several members with the average thickness of only 9~12 cm in the two drilling holes. This typical rhythmic pattern due to frequent alternation of concentration was evidenced by the variation of chemical composition and hydrogen isotopes of halite fluid inclusions. The presence of large number of primary fluid inclusions within chevron crystals and vertically oriented bottom-growth crystals showed that the halite were precipitated in shallow water (<60 cm). These features are direct evidence for this frequent alternation of dissolution and concentration of brines and terrigenous detrital-chemical shallow-water sedimentary model of these small rift-valley basins in Eastern China. [ABSTRACT FROM AUTHOR]

Petroleum sulfonates are widely used in chemical flooding in China. The samples are complicated and not all the fractions are effective. To recognize effective fraction with excellent interfacial activity and emulsifying property, a preparative liquid chromatography technology was adopted to perform the fraction separation for petroleum sulfonate. Structural composition, interfacial activity，emulsifying property and flooding efficiency of obtained fractions were also analyzed and discussed. It was shown that petroleum sulfonate can be effectively separated into different fractions with obvious structural differences, among which one fraction with the most excellent interfacial activity and the emulsifying property was recognized. The average molecular weight and molecular weight distribution range of this active fraction were 455.5 and 428–468, respectively, which are both crucial for activities. Alkylbenzene dicyclohexane sulfonates, alkyl indan sulfonates, and alkyl naphthalene sulfonates are major structure types, and alkyl chain length is mainly distributed between 12–15, 15–17 and 15–17 respectively. Besides, this active fraction is universal, and it can produce ultralow interfacial tension (~10−3 mN/m) and good emulsifying property against different crude oils including Xinjiang, Changqing, Liaohe Oilfields, etc. in China. The developed technology herein can be used to track and confirm the characteristics and/or active fraction in petroleum sulfonate accurately. • A preparative liquid chromatography method has been developed to separate petroleum sulfonates into different fractions. • Active fraction existing in petroleum sulfonate has been accurately tracked and confirmed. • The work will give some help for the selection of feedstock and the production of petroleum sulfonate. [ABSTRACT FROM AUTHOR]