Search

The Pearl River is one of China's large rivers, the second-largest river and the fourth-longest river in China. Its unique geography, landform, and climate conditions create unique fluvial geomorphological processes. Affected by human activities and climate change, the fluvial geomorphological processes in the Pearl River Basin have undergone significant changes in recent decades, seriously affecting the river's sustainable development. This paper critically reviews changes in fluvial geomorphological processes and analyzes influencing factors in the Pearl River Basin with a focus on possibilities for policy overhaul and strategic adjustments. [ABSTRACT FROM AUTHOR]

This paper analyzes data on the chemical composition of wetland waters, groundwaters, and river waters in the catchment area of Poyang Lake, which were obtained in the course of Russian–Chinese hydrogeochemical studies in 2013–2022. The bulk of the laboratory work was carried out at Tomsk Polytechnic University using the mass spectrometric method with inductively coupled plasma. It is shown that wetlands that are not used economically are a source of organic substances and their transformation products entering the groundwater of the upper hydrodynamic zone. An anthropogenic impact on surface and groundwaters has also been established, which manifests itself in a rather sharp increase in the concentrations of certain chemical elements and their compounds. However, at the same time, a significant ability of the region's water bodies to self-purify has been revealed. Thus, in the low-water periods of 2019 and 2022, a decrease in the contents of As, Cd, Ni, Sb, V, Mo, and W in the waters of the Jinjiang River was noted, which is 17–120 times and more just 100–200 m downstream from wastewater outlets. Based on the analysis of measurement results, thermodynamic calculations, mathematical modeling of hydrogeochemical processes, and published materials of other authors, it is concluded that the most likely explanation for this ability is a combination of the following factors: the precipitation of poorly soluble substances (calcium and magnesium humates and carbonates and clay minerals) with the total content of dissolved salts amounting to more than 300–400 mg/dm3; the coprecipitation of a number of microelements, which increases with a decrease in the effective diameter of sediment particles (0.003 mm or less); and the involvement of substances removed from the solution in biogeochemical processes, the intensity of which increases under favorable climatic conditions (such as in the catchment area of Poyang Lake). [ABSTRACT FROM AUTHOR]

China is a mountainous country with highly developed road geologic hazards, which pose a great threat to the construction and operation of highways, bridges, and tunnels and to the safety of people and property. This paper discussed the types, basic features, formation, and prevention conditions of road geologic hazards in China based on field research and study data collected thus far. The study considered an urban area of a city in southwest China as the center and a geological field investigation was performed over a total of 282 km on three important lifeline projects. The results show: Types of geologic hazards along the highways are mainly avalanches, debris flows, and landslides, respectively. Among them, the landslips are mainly distributed along the roads, with slip, dumping, and wrong break types as the main ones; the debris flows are widely distributed, mainly concentrated in the river valleys; and the unstable slopes are relatively few in number. Geological disasters are characterized by large-scale and concentrated triggering in time and space, and a single disaster can easily trigger other disasters, thus forming a chain of disasters. Neotectonic movement, seismic activity, topography, climatic conditions, stratigraphic lithology, and human activities are important factors leading to geologic hazards in the study area. This study is of great practical significance for reducing the occurrence of roadbed diseases and prolonging the service life of highways. [ABSTRACT FROM AUTHOR]

Identifying and quantifying the sources of climate impacts from land use and land cover change (LULCC) is necessary to optimize policies regarding LULCC for climate change mitigation. These climate impacts are typically defined relative to emissions of CO2, or sometimes emissions of other long-lived greenhouse gases. Here we use previously published estimates of the radiative forcing (RF) of LULCC that include the short-lived forcing agents O3 and aerosols, in addition to long-lived greenhouse gases and land albedo change, for six projections of LULCC as a metric for quantifying climate impacts. The LULCC RF is attributed to three categories of LULCC activities: direct modifications to land cover, agriculture, and wildfire response, and sources of the forcing are ascribed to individual grid points for each sector. Results for the year 2010 show substantial positive forcings from the direct modifications and agriculture sectors, particularly from India, China, and southeast Asia, and a smaller magnitude negative forcing response from wildfires. The RF from direct modifications, mainly deforestation activities, exhibits a large range in future outcomes for the standard future scenarios implying that these activities, and not agricultural emissions (which lead to more consistent RFs between scenarios), will drive the LULCC RF in the future. We show that future forest area change can be used as a predictor of the future RF from direct modification activities, especially in the tropics, suggesting that deforestation-prevention policies that 20 value land based on its C-content may be particularly effective at mitigating climate forcing originating in the tropics from this sector. Although, the response of wildfire RF to tropical land cover changes is not as easily scalable and yet imposes a non-trivial feedback onto the total LULCC RF. [ABSTRACT FROM AUTHOR]

As the world's largest carbon emitter, China is under great pressure to cut down carbon emissions. Understanding the evolution of carbon emissions across Chinese cities is important for policymakers when allocating carbon emission quota among these cities. This paper draws upon the Open-source Data Inventory for Anthropogenic CO2 to calculate city-level per capita carbon emissions in China from 2001 to 2016. Overall, we find that per capita carbon emissions of Chinese cities have been generally on the rise during the 2001–2016 period. However, there has been on average a modest decline in per capita carbon emissions of cities in China's Yangtze River Delta region and Pearl River Delta region from 2011 to 2016, after a remarkable increase during the 2001–2011 period. Besides, the average north-south gap has been enlarged, with northern cities having a relatively higher level of per capita carbon emissions. [ABSTRACT FROM AUTHOR]

This paper asks what should be the basis of a global environmental ethics. As Gao Shan has argued, the environmental ethics of Western philosophers such as Holmes Rolston and Paul Taylor is based on extending the notion of intrinsic value to that of objects of nature, and as such it is not very compatible with Chinese ethics. This is related to Gao's rejection of most--if not all--Western "rationalist" environmental ethics, a stance that I grant her for pragmatic reasons (though I remain neutral about it theoretically). Gao argues that the Daoist notion of living in harmony with nature can instead become the basis of a Chinese environmental ethics. However, the involved Daoist conception of living in harmony with nature is, in my view, based on an aesthetic property. The paper argues that despite the appeal of the Daoist view for a Chinese environmental ethics, an aesthetic property cannot provide the basis for a global environmental ethics. The paper also considers another version of Daoist environmental ethics, which does not rely on an aesthetic notion, but I argue that it too fails as such a candidate. As an alternative, the paper considers and applies contemporary Western thinkers on gratitude (such as Robert Emmons and Elizabeth Loder), proposing that gratitude to nature (environmental gratitude) can indeed provide the needed basis. [ABSTRACT FROM AUTHOR]

Groundwater level (GWL) prediction is important for ecological protection and resource utilization; it helps in formulating policies for artificial groundwater recharge, modifying the number of extraction wells, etc., and can support sustainable human development as well as inform water resource management decisions. However, climate change, anthropogenic impacts, and the complex coupling between surface water and groundwater increase the difficulty of predicting groundwater levels. The model proposed in this paper combines external data as well as multiple models. The method leverages long and short-term memory (LSTM) and convolutional neural network (CNN) models, combined with secondary modal decomposition and slime mould algorithm (SMA), together with an adaptive weight module (AWM). The study applies this method to predict GWL for three different hydrological conditions in China, specifically for the Jinan Baotu Spring, Heihu Spring, and Zhongtianshe watershed of Taihu Lake. A comparison of metrics such as mean absolute error and Nash efficiency coefficient for single and hybrid models shows that the model in this paper is more advantageous than the single model and other hybrid models. The interpretability of the model is enhanced by SHAP values that demonstrate the degree of contribution of the input variables. This paper uses SHAP analyses to identify the key drivers affecting groundwater levels. These factors must be detected in order to develop groundwater resource protection measures. [Display omitted] • Multivariate fusion data including hydrology and meteorology are used as model input. • A secondary modal decomposition module for historical groundwater level data was utilized. • The neural network hyperparameters are optimized using the slime mould algorithm. • Aggregate subsets of prediction with adaptive modules rather than linear summation. • The interpretable SHAP model measures the degree of influence of external variables. [ABSTRACT FROM AUTHOR]

The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang, Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark. This scenic area underwent a 30-year transformation, i.e., from a severe sand risk with spring water threatened by sand burial due to dune deformation, to restoration of the original sand flow field and mitigation of the sand burial problem. The current paper summarizes the research on the intensive monitoring of the dynamic change of star dunes near the spring, observation of wind and sand flow movement, and then restoring the harmonic vibration of the sand particles (singing sand) that were previously silenced. The existing and prospective impacts of anthropogenic and natural forces on the deformation of the sand dunes are investigated by integrated methods, guiding the implementation of mitigating measures with significant ameliorative effects. Contrast to common sand control practices that aim to reduce wind speed and stop blown sands, our research highlights the importance of maintaining the natural wind flow field in stabilizing surrounding dunes. These mitigation measures consist of removing excessive vegetation and newly constructed buildings to recover the original wind flow field and sand transport activity. Such research and mitigation efforts ensure the scientific protection and restoration of the special desert landform, and contribute to the mutual enhancement of the conservation and exploitation of this desert scenic spot and similar sites. [ABSTRACT FROM AUTHOR]

Human-driven dynamics of land cover types in the Tarim Basin are able to affect potential dust source regions and provide particles for dust storms. Analyses about dynamics of potential dust source regions are useful for understanding the effects of human activities on the fragile ecosystem in the extremely arid zone and also provide scientific evidence for the rational land development in the future. This paper therefore selected the Tarim Basin, NW China, as a representative study area to reveal spatiotemporal dynamics of land cover and their impacts on potential dust source regions. The results showed that farmland, desert and forest increased by 28.63, 0.64 and 29.27%, while grassland decreased by 10.29% during 1990-2010. The largest reclamation, grassland loss and desertification were 639.17 × 10, 2350.42 × 10 and 1605.86 × 10 ha during 1995-2000. The relationship between reclamation and grassland loss was a positive correlation, while a highly positive correlation was 0.993 between the desertification and grassland loss at different stages. The most serious dust source region was the desertification during 1990-2010 (1614.58 thousand ha), and the serious region was stable desert (40,631.21 thousand ha). The area of the medium and low dust source region was 499.08 × 10 and 2667.27 × 10 ha. Dramatic reclamation resulted in the desertification by destroying natural vegetation and breaking the balance of water allocation in various regions. [ABSTRACT FROM AUTHOR]

Taking the key research area in the arid region of North China—Minqin County—as a case, this paper analyzes the main factors impacting land desertification. Based on factor analysis method and the collection of data in the last 50 years, this paper researches the spatial changes of driving factors during the course of land desertification in Minqin, Gansu Province. The results of factor analysis indicate that the driving force of human factor on land desertification accounted for 56.33% in 1956–2004 and for 66.19% in 1981–2004, the driving force of nature factor on land desertification accounted for 11.29% in 1956–2004 and 8.11% in 1981–2004, and the synthesis of driving forces of human and natural factors accounted for 11.19% in 1956–2004 and for 14.88% in 1981–2004. This indicated that human driving force on land desertification was increasing in Minqin County gradually. [ABSTRACT FROM AUTHOR]

Drought, being one of the most devastating natural disasters, has a far- reaching impact. In the context of global warming, it becomes crucial to quantitatively and scientifically assess the effects of anthropogenic climate change on meteorological drought in China. This assessment not only enhances our understanding of anthropogenic climate change but also aids in formulating more effective strategies for managing the risks associated with meteorological drought. This study employs the standardized precipitation evapotranspiration index (SPEI) to compute drought events by utilizing both observational data and counterfactual climate data (i.e., detrended observations). Subsequently, it analyzes the impact of anthropogenic climate change on the characteristics of drought, including frequency, intensity, duration, and affected area, in China as well as nine major river basins from 1960 to 2019. The outcomes of the analysis reveal that based on observational data, there is a discernible upward trend in the frequency, intensity, duration, and affected area of meteorological droughts in China. Notably, the regions experiencing an increase in frequency, intensity, and duration are primarily situated in the northeastern part of the Northwestern Rivers basin, the central and western parts of the Yellow River basin, the central and northern parts of the Yangtze River basin, the western part of the Southeastern River basins, and the eastern part of the Pearl River basin. Conversely, when considering a counterfactual climate scenario, the frequency and intensity of meteorological droughts in China demonstrate an upward trend, while the duration and affected area exhibit a downward trend. The impact of anthropogenic climate change on China has been evident in the increased frequency, intensity, duration, and affected area of droughts. Specifically, regions located in the northeastern parts of Northwest River basins, the southern part of the Songliao River basin, the northern part of the Haihe River basin, the central- northern part of the Yangtze River basin, the eastern part of the Pearl River basin, and the western part of the Southwest River basins have experienced amplified levels of drought. Anthropogenic climate change is highlighted as the primary factor influencing the observed drought characteristics changes in China, with contribution rates of 84.67%, 75.25%, 190.32%, and 133.99% for changes in the increased drought frequency, intensity, duration, and affected area, respectively. These changes have significant implications for water resource management and agricultural practices in the affected regions. [ABSTRACT FROM AUTHOR]

Loss of pedodiversity is a worsening land degradation issue worldwide. Knowledge of rare and endangered soils is critical for the protection of pedodiversity. However, such knowledge remains limited, especially for mountain regions with intensive human disturbance. In this paper, rare and endangered soils were identified using the Harmonized World Soil Database (HWSD), and their spatial distributions were determined for Taihang Mountain region, North China. Furthermore, the effects of natural (elevation, precipitation, temperature, slope gradient, soil parent, and vegetation) and human (farming and population density) factors on rare and endangered soils were analyzed. The results showed that based on the second‐level HWSD classification, a total of 94 soil types were identified in Taihang Mountain region, 36 of which were rare and 7 endangered soils. It implied that there was the need to protect soil resources in this region. Cluster analysis showed that Dystric Podzoluvisols and Mollic Gleysols were the most endangered soils in terms of both area and distribution, suggesting that these soil types needed to be protected. Most of the rare and endangered soils were distributed in the northern of Taihang Mountain, indicating that the northern part needed more attention. Correlation analysis showed that the effect of human factors on rare and endangered soils was more important than that of natural factors, confirming that human activities were largely responsible for the occurrence of rare and endangered soils. Such results provided not only further understanding of pedodiversity but also useful information for protection of soil resources and control of land degradation. [ABSTRACT FROM AUTHOR]

Exploitation of groundwater has greatly increased since the 1970s to meet the increased water demand due to fast economic development in China. Correspondingly, the regional groundwater level has declined substantially in many areas of China. Water sources are scarce in northern and northwestern China, and the anthropogenic pollution of groundwater has worsened the situation. Groundwater containing high concentrations of geogenic arsenic, fluoride, iodine, and salinity is widely distributed across China, which has negatively affected safe supply of water for drinking and other purposes. In addition to anthropogenic contamination, the interactions between surface water and groundwater, including seawater intrusion, have caused deterioration of groundwater quality. The ecosystem and geo-environment have been severely affected by the depletion of groundwater resources. Land subsidence due to excessive groundwater withdrawal has been observed in more than 50 cities in China, with a maximum accumulated subsidence of 2-3 m. Groundwater-dependent ecosystems are being degraded due to changes in the water table or poor groundwater quality. This paper reviews these changes in China, which have occurred under the impact of rapid economic development. The effects of economic growth on groundwater systems should be monitored, understood and predicted to better protect and manage groundwater resources for the future. [ABSTRACT FROM AUTHOR]

Human impact on the coastal plain of Southeast China has been well studied over late Holocene timescales; however, an understanding of anthropogenic impact in mountainous regions is still lacking. In this paper, we present records of vegetation, fire, and human impact, spanning the past 4000 years, with a resolution of ∼40 years, obtained from an upland peatland in Southeast China. The results reveal that climate change (dominated by the evolution of the East Asia Monsoon) was the most critical factor controlling vegetation before 1.0 cal kyr BP, while human impact gradually emerged as the primary driver after 1.0 cal kyr BP in the mountains of Southeast China. As such, the record of anthropic impact in mountainous regions lagged behind the signal from the coastal plains by some 2000–4000 years. As the population migrating from northern China dispersed into the mountainous regions of Southeast China, demand for agricultural land promoted slash-and-burn cultivation and the destruction of broad-leaf forest. • Three climatic stages identified spanning 4.0 cal kyr BP based on pollen and charcoal analysis. • Significant anthropogenic impact on mountain vegetation of Southeast China occurred in 1.0 kyr BP, lagged coastal plains by 2000–4000 years. • The population migrating from northern China dispersed into the mountainous regions of southeastern China in 1.0 kyr BP, urgent demand for cultivated land. [ABSTRACT FROM AUTHOR]

Discriminating the provenance of fine-grained sediments is crucial for reconstructing paleogeography, sedimentary processes, and paleoclimate. In this paper, we investigate the South Bohai Coast to better understand source-to-sink systems in East Asia. This region is influenced by both distant sources such as the large-scale Yellow River and small local river sources flowing from the Luzhong Mountain area. Two Holocene sedimentary cores, dated using optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C chronology, were used to investigate the provenance of the fine-grained sediments over the last 7 kyrs. Clay mineralogy and relevant non-linear modeling were employed for provenance discrimination. The results show that the fine-grained sediments along the South Bohai Coast were mainly derived from the Yellow River during the periods of 7.0–5.4 ka and 4.5–2.6 ka, respectively, while the input from the Luzhong Mountain-derived rivers was greater during 5.4–4.5 ka and 2.6–0.2 ka, respectively. Fluvial activities and marine-terrestrial interaction driven by climate factors such as East Asian winter monsoon, temperature, and precipitation in river basins, dominantly influenced the provenance of fine-grained sediments from 7.0 to 2.6 ka. Anthropogenic impact on provenance increased after 2.6 ka. The chronology of the two cores showed extremely rapid sedimentation rate transitions at 5.2 ka and 1.5 ka, respectively, very likely attributed to anthropogenic-induced rapid progradation. Our study provides a model for better understanding the paleoenvironmental and paleogeographic evolution of a coastal area where multiple sources exist. • Anthropogenically high sedimentation rate in the South Bohai Coast in late Holocene. • Provenance discrimination of the fine-grained sediments in the South Bohai Coast since the mid-Holocene. • The major source of the fine-grained sediments in the South Bohai Coast changed episodically. [ABSTRACT FROM AUTHOR]

While previous studies have largely focused on anthropogenic warming characterized by surface air temperature, little is known about the behaviors of human‐perceived temperature (HPT), which describe the "feels‐like" equivalent temperature by considering the joint effects of temperature, humidity and/or wind speed. Here we adopted an optimal fingerprinting method to compare seasonal mean HPTs in China with those from simulations conducted with multiple climate models participating in the Coupled Model Intercomparison Project Phase 6. We found clear anthropogenic signals in the observational records of changes in both summer and winter HPTs over the period 1971–2020. Moreover, the anthropogenic greenhouse gas influence was robustly detected, with clear separation from natural and anthropogenic aerosol forcings. The anthropogenic greenhouse gas forcing plays the dominant role (>90%) of human‐perceived warming. Urbanization effects contribute slightly and moderately to the estimated trends in summer and winter HPTs, respectively, in addition to the effects of external forcing. Plain Language Summary: Human influences have been identified in the observed warming quantified by surface air temperature (SAT), but SAT alone is inadequate as a metric for human thermal comfort. Here we focus on human‐perceived temperature (HPT), which describes the "feels‐like" equivalent temperature by considering the joint effects of temperature, humidity, and/or wind speed. We isolate anthropogenic impacts on the observed increase in summer and winter HPTs in China during 1971–2020 by comparing observations with state‐of‐the‐art climate models. Results show that the influence of anthropogenic greenhouse gas is detected, with clear separation from other external forcings such as solar and volcanic activities and anthropogenic aerosols. The human‐induced greenhouse gas increases are also found to explain most (>90%) of the observed human‐perceived warming. Along with the effects of large‐scale anthropogenic forcing, urbanization effects also have a slight to moderate influence on the estimated trends in summer and winter HPTs. Our work is an early attempt to provide quantitative evidence for the physiological impacts of anthropogenic global warming and local urbanization on human beings. Key Points: The warming is quantified by human‐perceived temperature that considers the joint effects of temperature, humidity and/or wind speedHuman influence could be robustly detected in both summer and winter human‐perceived warmingThe observed increase in human‐perceived temperature is mostly attributed to anthropogenic greenhouse gas increases [ABSTRACT FROM AUTHOR]

Trace metals from natural and anthropogenic sources impact the atmospheric environment and enter the soil through dry and wet atmospheric deposition, ultimately affecting human health. In this study, we established an emission inventory of Pb, As, Cr, and Cd in East Asia (80° E–140° E, 15° N–50° N) for the year 2017, including dust and anthropogenic sources from both land and marine. We modified the Community Multiscale Air Quality (CMAQ) model to provide gridded data on concentrations, as well as dry and wet atmospheric deposition fluxes of metals, with a focus on mainland China. The emissions of Pb, As, Cr, and Cd in East Asia were 19,253, 3415, 3332, and 9379 tons, respectively, in 2017, with 55%, 69%, 25%, and 58% distributed in the fine mode. The spatial distribution of atmospheric concentrations and dry deposition of trace metals was similar to that of emissions, while the spatial distribution of precipitation-related wet deposition was further east and greater in the south than in the north. In mainland China, the average bulk-deposition fluxes of Pb, As, Cr, and Cd were 1036.5, 170.3, 465.9, and 185.0 μg·m−2·year−1, respectively. Our study provides gridded data on trace metals in mainland China, which can be used for assessing air quality, human exposure risks, and metal inputs to soils. [ABSTRACT FROM AUTHOR]

In many rapidly urbanizing countries like China, wetlands are constantly affected by anthropogenic factors such as landscaping, additional abstractions, reduction in catchment perviousness, etc. Thus, modeling of such anthropogenic factors should be explicitly considered when simulating wetlands. In this paper, the wetland module in a distributed hydrological model, SWAT, is modified to simulate the artificial water input to the designated wetlands. Local river runoff is used as the water sources to study the wetland restoration potential and to analyze the effects on local hydrological cycle and sea outflow. The QingDianWa depression, near Tianjin city, China, is used as a case study to study the restoration impact. Results showed that after restoration, the QinDianWa depression can reduce the potential impact of flooding by an average of 61 million m3 per year, increase the annual surface runoff by about 32 million m3 in non-flood seasons, and increase groundwater recharge by 9.4 million m3. This illustrated the importance of wetland restoration on flood control, river flow increase, groundwater recharge, and flood reclamation. But with local water resources is far from meeting the demands of wetland restoration, the actual restored water surface area is only 21.5 and 40.9 km2 for the designated surface areas of 60 and 150 km2 respectively. Compared with nature wetlands without human disturbance, the anthropogenic effect of reduction of runoff and groundwater recharge may be attributed to large amount of human consumption of local water. However, the results showed that the aims of restoring Tianjin wetlands cannot be achieved fully by relying solely on local water resources. It is necessary to consider a combination of external sources of water and using artificial recharge from reclaimed water. [ABSTRACT FROM AUTHOR]

Anthropogenic disturbances have caused major landscape changes in the forests of northeastern China during the past 50 years. In particular, continuous over-deforestation has greatly decreased the region's forest quality. Ecological footprint analysis generates aggregated information about a population's demand on nature and the population regional biological capacity. To show the forest change and the population's ecological demand on the study area, this paper presents an ecological footprint time series for the Songling Forestry Bureau in northeastern China from 1965 to 2000. The paper shows conventional ecological footprint time series and area demand time series -- under global, Chinese and local yearly yields -- to study the biological productivity of Songling. In this study, biological capacity was calculated based on a conventional approach. The results demonstrate that the ecological footprint has increased slightly and continuously during the 35-year timespan, while the biological capacity has decreased dramatically. These effects have been caused mainly by the depletion of forest resources. The results also yield much information about natural changes and socioeconomic dynamics, as well as the driving factors for these changes, of which the most important is forest management policy. [ABSTRACT FROM AUTHOR]

In the past decades, continuous efforts have been made at a national level to reduce Nitrogen Dioxide (NO2) emissions in the atmosphere over China. However, public concern and related research mostly deal with tropospheric NO2 columns rather than ground-level NO2 concentrations, but actually ground-level NO2 concentrations are more closely related to anthropogenic emissions, and directly affect human health. This paper presents one method to derive the ground-level NO2 concentrations using the total column of NO2 observed from the Ozone Monitoring Instrument (OMI) and the simulations from the Community Multi-scale Air Quality (CMAQ) model in China. One year's worth of data from 2014 was processed and the results compared with ground-based NO2 measurements from a network of China's National Environmental Monitoring Centre (CNEMC). The standard deviation between ground-level NO2 concentrations over China, the CMAQ simulated measurements and in-situ measurements by CNEMC for January was 21.79 μg/m3, which was improved to a standard deviation of 18.90 μg/m3 between our method and CNEMC data. Correlation coefficients between the CMAQ simulation and in-situ measurements were 0.75 for January and July, and they were improved to 0.80 and 0.78, respectively. Our results revealed that the method presented in this paper can be used to better measure ground-level NO2 concentrations over China. [ABSTRACT FROM AUTHOR]

Copyright of Regional Studies is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The role of human activity in shaping the terrestrial environment has been a core scientific issue of interest across various disciplines. However, it remains unclear whether there are significant differences in the patterns of the anthropogenic impact on the terrestrial environment in terms of spatial and temporal dimensions, and we are yet to identify the underlying factors that have driven it. Here, we present an analysis of sporopollen and geochemical proxies from a section of the Anjiangbei site (AJB) on the Yunnan Plateau, spanning the Ming–Qing period, in order to explore the spatio-temporal variation in the anthropogenic impact on the terrestrial environment in the Lake Dian basin. Integrating the reported multidisciplinary evidence, we aim to reveal the influencing factors of anthropogenic impact. Our results show that there were remarkable differences in anthropogenic impact on the terrestrial environment in the Lake Dian basin between the Late Bronze Age and the Ming–Qing period. Changes in crop vegetation and the forest were all affected by human activity in the Lake Dian basin during the two periods, and were more evident during the Ming–Qing period. The heavy metal pollution in the soil was obvious during the Ming–Qing period. The increase in the intensity of human activity, especially the rise in population, could be attributed to changes in the hydrological environment in the Lake Dian basin during the Late Bronze Age and to geopolitical change during the Ming–Qing period. This study reveals the different patterns in human impact on the terrestrial environment in the Lake Dian basin during the Late Bronze Age and the Ming–Qing period, providing new evidence to enable a deeper understanding of past human–environment interactions on the Yunnan Plateau. [ABSTRACT FROM AUTHOR]

The nitrate radical (NO 3) is a critical nocturnal atmospheric oxidant in the troposphere, which widely affects the fate of air pollutants and regulates air quality. Many previous works have reported the chemistry of NO 3 in inland regions of China, while fewer studies target marine regions. Here, we present a field measurement of the NO 3 reservoir, dinitrogen pentoxide (N 2 O 5), and related species at a typical marine site (Da Wan Shan Island) located in the South China Sea in the winter of 2021. Two patterns of air masses were captured during the campaign, including the dominant airmass from inland China (IAM) with a percentage of ∼ 84 %, and the airmass from eastern coastal areas (CAM) with ∼ 16 %. During the IAM period, the NO 3 production rate reached 1.6 ± 0.9 ppbv h -1 due to the transportation of the polluted urban plume with high NO x and O 3. The average nocturnal N 2 O 5 and the calculated NO 3 mixing ratios were 119.5 ± 128.6 and 9.9 ± 12.5 pptv, respectively, and the steady-state lifetime of NO 3 was 0.5 ± 0.7 min on average, indicating intensive nighttime chemistry and rapid NO 3 loss at this site. By examining the reaction of NO 3 with volatile organic compounds (VOCs) and N 2 O 5 heterogeneous hydrolysis, we revealed that these two reaction pathways were not responsible for the NO 3 loss (< 20 %) since the NO 3 reactivity (k (NO 3)) towards VOCs was small (5.2×10-3 s -1) and the aerosol loading was low. Instead, NO was proposed to significantly contribute to nocturnal NO 3 loss at this site, despite the nocturnal NO concentration always below the parts per billion by volume level and near the instrument detection limit. This might be from the local soil emission or something else. We infer that the nocturnal chemical NO 3 reactions would be largely enhanced once without NO emission in the open ocean after the air mass passes through this site, thus highlighting the strong influences of the urban outflow to the downwind marine areas in terms of nighttime chemistry. During the CAM period, nocturnal ozone was higher, while NO x was much lower. The NO 3 production was still very fast, with a rate of 1.2 ppbv h -1. With the absence of N 2 O 5 measurement in this period, the NO 3 reactivity towards VOCs and N 2 O 5 uptake were calculated to assess NO 3 loss processes. We showed that the average k (NO 3) from VOCs (56.5 %, 2.6 ± 0.9 × 10 -3 s -1) was higher than that from N 2 O 5 uptake (43.5 %, 2.0 ± 1.5 × 10 -3 s -1) during the CAM period, indicating a longer NO 3 / N 2 O 5 lifetime than that during IAM period. This study improves the understanding of the nocturnal NO 3 budget and environmental impacts with the interaction of anthropogenic and natural activities in marine regions. [ABSTRACT FROM AUTHOR]

Monitoring shoreline movements is essential for understanding the impact of anthropogenic activities and climate change on the coastal zone dynamics. The use of remote sensing allows for large-scale spatial and temporal studies to better comprehend current trends. This study used Landsat 5 (TM), Landsat 8 (OLI), and Sentinel-2 (MSI) remote sensing images, together with the Otsu algorithm, marching squares algorithm, and tidal correction algorithm, to extract and correct the coastline positions of the east coast of Laizhou Bay in China from 1984 to 2022. The results indicate that 89.63% of the extracted shoreline segments have an error less than 30 m compared to the manually drawn coastline. The total length of the coastline increased from 166.90 km to 364.20 km, throughout the observation period, with a length change intensity (LCI) of 3.11% due to the development of coastal protection and engineering structures for human activities. The anthropization led to a decrease in the natural coastline from 83.33% to 13.89% and a continuous increase in the diversity and human use of the coastline. In particular, the index of coastline diversity (ICTD) and the index of coastline utilization degree (ICUD) increased from 0.39 to 0.79, and from 153.30 to 390.37, respectively. Over 70% of the sandy beaches experienced erosional processes. The shoreline erosion calculated using the end point rate (EPR) and the linear regression rate (LRR) is 79.54% and 85.58%, respectively. The fractal dimension of the coastline shows an increasing trend and is positively correlated with human activities. Coastline changes are primarily attributed to interventions such as land reclamation, aquaculture development, and port construction resulting in the creation of 10,000.20 hectares of new coastal areas. Finally, the use of Kalman filtering for the first time made it possible to predict that approximately 84.58% of the sandy coastline will be eroded to varying degrees by 2032. The research results can provide valuable reference for the scientific planning and rational utilization of resources on the eastern coast of Laizhou Bay. [ABSTRACT FROM AUTHOR]

Mountainous rivers are critical in transporting dissolved organic carbon (DOC) from terrestrial environments to downstream ecosystems. However, how geomorphologic factors and anthropogenic impacts control the composition and export of DOC in mountainous rivers remains largely unclear. Here, we explore DOC dynamics in three subtropical mountainous catchments (i.e., the Yinjiang, Shiqian, and Yuqing catchments) in southwest China, which are heavily influenced by anthropogenic activities. Water chemistry, stable and radioactive carbon isotopes of DOC (δ13CDOC and Δ14CDOC), and optical properties (UV absorbance and fluorescence spectra) were employed to assess the biogeochemical processes and controlling factors on riverine DOC. The radiocarbon ages of DOC in the Yinjiang River varied widely from 928 years BP to the present. Stepwise multiple regression analyses and partial least square path models revealed that geomorphology and anthropogenic activities were the major drivers controlling DOC concentrations and DOM characteristics. Catchments with higher catchment slope gradients were characterized by lower DOC concentrations, enriched δ13CDOC and Δ14CDOC , and more aromatic dissolved organic matter (DOM), which were opposite to catchments with gentle catchment slopes. Variabilities in DOC concentrations were also regulated by land use, with higher DOC concentrations in urban and agricultural areas. Furthermore, DOM in catchments with a higher proportion of urban and agricultural land uses was less aromatic, less recently produced, and exhibited a higher degree of humification and more autochthonous humic-like DOM. This research highlights the significance of incorporating geomorphologic controls on DOC sources and anthropogenic impacts on DOM composition into the understanding of DOC dynamics and the quality of DOM in mountainous rivers, which are globally abundant. [ABSTRACT FROM AUTHOR]

In this paper, the RIEMS 2.0 model, source emission in 2006 and 2010 are used to simulate the distributions and radiative effects of different anthropogenic aerosols over China. The comparison between the results forced by source emissions in 2006 and 2010 also reveals the sensitivity of the radiative effects to source emission. The results are shown as follows: (1) Compared with those in 2006, the annual average surface concentration of sulfate in 2010 decreased over central and eastern China with a range of -5 to 0 g/m³; the decrease of annual average aerosol optical depth of sulfate over East China varied from 0.04 to 0.08; the annual average surface concentrations of BC, OC and nitrate increased over central and eastern China with maximums of 10.90, 11.52 and 12.50 g/m³, respectively; the annual aerosol optical depths of BC, OC and nitrate increased over some areas of East China with extremes of 0.006, 0.007 and 0.008, respectively. (2) For the regional average results in 2010, the radiative forcings of sulfate, BC, OC, nitrate and their total net radiative forcing at the top of the atmosphere over central and eastern China were -0.64, 0.29, -0.41, -0.33 and -1.1 W/m², respectively. Compared with those in 2006, the radiative forcings of BC and OC in 2010 were both enhanced, while that of sulfate and the net radiative forcing were both weakened over East China mostly. (3) The reduction of the cooling effect of sulfate in 2010 produced a warmer surface air temperature over central and eastern China; the maximum value was 0.25 K. The cooling effect of nitrate was also slightly weakened. The warming effect of BC was enhanced over most of the areas in China, while the cooling effect of OC was enhanced over the similar area, particularly the area between Yangtze and Huanghe Rivers. The net radiative effect of the four anthropogenic aerosols generated the annual average reduction and the maximum reduction were -0.096 and -0.285 K, respectively, for the surface temperature in 2006, while in 2010 they were -0.063 and -0.256 K, respectively. In summary, the change in source emission lowered the cooling effect of anthropogenic aerosols, mainly because of the enhanced warming effect of BC and weakened cooling effect of scattering aerosols. [ABSTRACT FROM AUTHOR]

The Ning-Meng reach of the Yellow River in China is located in a high-latitude area, and river freezes up and breaks up every year, leading to ice flood and disaster. Since the 1990s, due to the rising winter temperatures, river channel shrinkage and impacts of reservoir operation, the river ice regime of the Ning-Meng reach has changed. This paper investigated reservoir operation effect on river ice regime by eliminating the impact of climatic conditions, and the test method could be applied to other rivers, where similar anthropogenic impacts can be suspected to affect the river ice regime. The results show that compared to the statistics when there were no reservoirs, the duration of ice freezing days reduced 8-33 days, and the ice cover thickness was 16-25 cm thinner than that without reservoirs. The average number of ice flood incidents per year decreased from 11.61 to 3.25, and the number of disasters reduced from 1.69 to 1.41. Moreover, the changes induced by reservoirs joint operation may vastly exceed that by single reservoir operation. The smaller is the distance to the upstream reservoir, the more obvious is the impact from the reservoir. [ABSTRACT FROM AUTHOR]

This paper examines the short-run climate variability (change in the levels of temperature and precipitation) with a focus on the Manas River Valley, North-Western China, over the past 50 years (1956 to 2006) using data collected from four meteorological stations. The results show that the annual mean temperature had a positive trend, with temperature increasing at 0.4 °C per decade. Application of the Mann-Kendall test revealed that the overall positive trend became statistically significant at the p = 0.95 level only after 1988. The increase in temperature was most marked in winter and spring (0.8 and 0.7 °C per decade, respectively), absent in summer and very small in autumn (0.1 °C per decade). Concerning precipitation, our results indicate a negative but not significant trend for the period between 1956 and 1982, while annual total precipitation tended to increase thereafter and the increase was mainly during the crop growing-season. Concerning variability in temperature and precipitation, the characteristic time scales were identified by application of wavelet analysis. For temperature the quasi-decadal variations were found on time scales between approximately 5 and 15 years, with a peak in wavelet variance on a time scale of 9 years. For precipitation, the most striking features were a precipitation increase (6.7 mm per decade) during the crop growing season. Irregularities and abrupt changes in both temperature and precipitation were more common at scales less than 10 years, indicating the complexity and uncertainty in the short-period climate variability. Possible causes of climate variability in the Manas River Valley may include anthropogenic factors such as intensive human activity and the expansion of both farmland and irrigation. Global climate variability might also have some impacts on the local climate variability; analyses of local and regional climate trends can better inform local adaptation actions for global impacts. [ABSTRACT FROM AUTHOR]

The agro-pastoral ecotone serves as an important ecological transition zone between grassland and cropland. It plays a crucial role in providing forage and maintaining the ecological security of Northern China. China has initiated many ecological restoration projects in the agro-pastoral ecotone. Separating the affecting factors of anthropogenic activities and natural factors change on grassland may help guide future ecological restoration projects. This study investigated the grassland change over the agro-pastoral ecotone in Inner Mongolia (APEI) using land use data, vegetation index, and monthly climate data, social and economic data from 2010 to 2020. Two indicators were introduced to evaluate the grassland change in quality and quantity. The average annual maximum NDVI of grassland within each sample was used as a proxy for grassland quality, and the proportion of grassland within each sample was used as a proxy for grassland quantity. The driving mechanisms of grassland quality were examined on different types of grassland. The results showed that (1) from 2010 to 2020, the quantity of grassland in APEI slightly decreased while the quality of the grassland significantly improved; (2) the change in grassland quality was jointly caused by natural factors and human activities, with 66.77% being attributed to natural factors and 33.23% to human activities. In some areas, the alteration in grassland quality was solely determined by either the impacts of natural factors or human-induced disturbances; and (3) temperature and precipitation played different roles in affecting grassland quality among different types of grassland. In some areas, anthropogenic activities, such as farmland and population, would affect grassland quality. The findings of this study would contribute to the understanding of the mechanism of ecological environmental changes in the agro-pastoral ecotone and guide the planning and implementation of future ecological restoration projects in agro-pastoral areas. [ABSTRACT FROM AUTHOR]

Anthropogenic water regulation activities, including reservoir interception, surface water withdrawal, and groundwater extraction, alter riverine hydrologic processes and affect dissolved organic carbon (DOC) export from land to rivers and oceans. In this study, schemes describing soil DOC leaching, riverine DOC transport, and anthropogenic water regulation were developed and incorporated into the Community Land Model 5.0 (CLM5.0) and the River Transport Model (RTM). Three simulations by the developed model were conducted on a global scale from 1981–2013 to investigate the impacts of anthropogenic water regulation on riverine DOC transport. The validation results showed that DOC exports simulated by the developed model were in good agreement with global river observations. The simulations showed that DOC transport in most rivers was mainly influenced by reservoir interception and surface water withdrawal, especially in central North America and eastern China. Four major rivers, including the Danube, Yangtze, Mississippi, and Ganges rivers, have experienced reduced riverine DOC flows due to intense water management, with the largest effect occurring in winter and early spring. In the Danube and Yangtze river basins, the impact in 2013 was 4 to 5 times greater than in 1981, with a retention efficiency of over 50 %. The Ob river basin was almost unaffected. The total impact of anthropogenic water regulation reduced global annual riverine DOC exports to the ocean by approximately 13.36 ± 2.45 Tg C yr -1 , and this effect increased from 4.83 % to 6.20 % during 1981–2013, particularly in the Pacific and Atlantic oceans. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are the main precursors of pollution from ground ozone (O3) and PM2.5, which cause the deterioration of urban air quality. The emissions of VOCs from industrialized areas are significant and their characteristics are complex, which nowadays contribute significantly to the challenges of investigating the emission inventory. Taking a typical industrialized area in Tianjin as a case study, the anthropogenic VOCs emission inventory for 2020 was established in this study by using the activity data from a large-scale survey and the latest emission factors. The impact of VOCs on the environment was analyzed from the perspective of the combined control of PM2.5 and O3. The results showed that the total emission of VOCs in 2020 was about 1.68 Gg, mainly from industrial processes and mobile sources, which accounted for 38.4% and 36.5% of the total emissions, respectively. The top 10 emitted VOCs were toluene, acetone, ethylbenzene, m/p-xylene, i-pentane, n-hexane, formaldehyde, benzene, ethyl acetate and ethylene. The dominant species of O3 formation potential (OFP) were almost all aromatic hydrocarbons and alkenes, with m/p-xylene contributing the most to the OFP emissions (8.90%). The top 10 secondary organic aerosols formation potential (SOAP) emission species were aromatic hydrocarbons and long-chain alkanes, and the largest emission came from toluene (39.9%). An analysis of an ADMS diffusion model showed that VOCs emitted from traffic-heavy main roads and industrialized central areas had the greatest impact on the air quality in the surrounding areas. The VOCs concentration was higher in winter due to unfavorable meteorological conditions. Our research updated the VOC inventory of industrialized areas and evaluated VOCs species reactivity and their impact on ambient air quality. [ABSTRACT FROM AUTHOR]

Under increasing anthropogenic pressure, species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations. The critically endangered Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis), once commonly observed in the Yangtze River-Poyang Lake junction, is now rarely seen in the river-lake corridor. In this study, static passive acoustic monitoring techniques were used to detect the biosonar activities of the Yangtze finless porpoise in this unique corridor. Generalized linear models were used to examine the correlation between these activities and anthropogenic impacts from the COVID-19 pandemic lockdown and boat navigation, as well as environmental variables, including hydrological conditions and light levels. Over approximately three consecutive years of monitoring (2020–2022), porpoise biosonar was detected during 93% of logged days, indicating the key role of the corridor for finless porpoise conservation. In addition, porpoise clicks were recorded in 3.80% of minutes, while feeding correlated buzzes were detected in 1.23% of minutes, suggesting the potential existence of localized, small-scale migration. Furthermore, both anthropogenic and environmental variables were significantly correlated with the diel, lunar, monthly, seasonal, and annual variations in porpoise biosonar activities. During the pandemic lockdown period, porpoise sonar detection showed a significant increase. Furthermore, a significant negative correlation was identified between the detection of porpoise click trains and buzzes and boat traffic intensity. In addition to water level and flux, daylight and moonlight exhibited significant correlations with porpoise biosonar activities, with markedly higher detections at night and quarter moon periods. Ensuring the spatiotemporal reduction of anthropogenic activities, implementing vessel speed restrictions (e.g., during porpoise migration and feeding), and maintaining local natural hydrological regimes are critical factors for sustaining porpoise population viability. [ABSTRACT FROM AUTHOR]

This paper is to present an efficient approach to enriching the quantification model of human-riverine interactions and its anthropogenic impact by a retrospective study on one of the four most famous historical hydraulic projects in China, the Tuoshan Weir. It was constructed in 833 AD and had trajectories of natural resilience and hydraulic engineering maturity more than thousand years. Extensive historical data and maturation procedure of the hydraulic system were used judiciously to examine the spatial patterns of the long-term water conservancy system with agriculture, urbanization and civilization of Ningbo City in Zhejiang Province, Southeast China. Interaction framework is assessed from historical perspective and the deposition rate ( DR) is calculated by analyzing the continuous increase of the Tuoshan Weir height. The results show that the declining DR during the 1180 years guaranteed the beneficial role the Tuoshan Weir played in spite of some negative river responses caused by the increase of sediment deposition and decrease of fresh water-retention capacity. The following up revamped workings and well matured hydraulic system around the Tuoshan Weir also contribute a lot to the designed mission of the weir. We conclude that hydraulic system maturation is very important for the proper function and life span of huge hydraulic projects. [ABSTRACT FROM AUTHOR]

Due to the increasing high rate of economic development and population, groundwater resources of Jiansanjiang in China are affected by both anthropogenic and natural factors. In order to achieve optimal local allocation of water resources and promotion of local economic development, a suitable method for measuring the complexity of groundwater resources system is very important. In this paper, time series fractal dimension based on the curve length calculation combined with the artificial fish algorithm for the intelligent efficient fitting of data were applied to diagnose groundwater sequence in Jiansanjiang. Fractal dimension values of monthly groundwater depth series in 15 districts of Jiansanjiang Branch Bureau and their average complexity were calculated and the results revealed that the complexity of north district is the highest while that of southern district is the lowest. Our analysis also revealed that the most important influencing factor of local groundwater depth dynamics variation is the human activities and results confirmed that combined fractal theory and artificial fish algorithm for extraction hydrological time series complexity feature is feasible and can be applied in studying regional hydrological process. It also provided a scientific basis for achieving sustainable utilization of the regional groundwater resource. [ABSTRACT FROM AUTHOR]

Human activities can have dramatic effects on the environment so that evaluating the anthropogenic driving forces is an important issue in the consideration of how humans impact the world. In this paper, ecological footprint (EF) was used as an aggregate index of total human impacts in 31 provinces in mainland China during 2010. The STIRPAT model was employed to analyze the major anthropogenic drivers of EF. The empirical results demonstrate that great disparities of EF exist at the spatial scale. Provinces with the largest total EF are mostly distributed in the populated east coast of China, whereas provinces with the lowest total EF are mostly found in west China. Similar to EF, ecological deficit (ED) is a dominant characteristic of most municipal areas in China. The results of STIRPAT show that population has the largest potential effect on the Chinese environment at the provincial scale, followed by EF intensity, affluence, percentage of gross domestic product (GDP) from the industrial sector, age structure, and per capita land area. Urbanization has negative effects on EF disparities, but it is not an inevitable factor in this case. This study is helpful to recognizing the human effects on environment and helps to facilitate the management of sustainable development across China. [ABSTRACT FROM AUTHOR]

Baiyangdian Lake is the biggest natural freshwater wetland in North China Plain. It provides important ecosystem services such as water regulation and supply, reed production and biodiversity protection. Baiyangdian Lake, however, was threatened by lack of freshwater in recent decades. In this paper, the hydrological changes of the lake were quantified using historical data of water level and groundwater table, and satellite images. In addition, the relationship between water level and socioeconomic development of the basin was investigated. The result revealed a significant decreasing trend of water level in the lake. Water level and groundwater table of Baiyangdian Lake decreased rapidly, caused by the great increase of water withdrawal and consumption due to socioeconomic development in the basin. In particular, population growth and the expansion of irrigated agriculture were two major contributors to the decline of water level and groundwater table. While precipitation was positively correlated with water level, it has less impact on water level and groundwater table than human activities. The diversion of water to the lake raised the water level temporarily and had significant benefits on the wetland ecosystem. The best way to solve ecological problems of Baiyangdian Lake, however, is to control the growth of population, adjust the industrial structure, control land use conversion and improve water use efficiency at the basin scale. [ABSTRACT FROM AUTHOR]

This paper analyzes legal remedies for marine ecological damage as provided in Article 90, Section 2 of the Marine Environment Protection Law of the People's Republic of China. In doing so, the paper examines the Tasman Sea Oil Spills Case, the first civil case in China to claim marine ecological damage involving foreign interests. The paper finds that many issues arise in practice due to the simplicity of the relevant legal provisions. The existing international treaties on marine oil pollution damage caused by ships do not cover marine ecological damage. However, domestic courts of some countries have relevant judicial practice on the matter. Hence, it is urgent to establish a set of new rules on marine ecological damage compensation in China and to specify the claimants, the scope for compensation and the measure of indemnity with the aim of providing an effective legal remedy for marine ecological damage. [ABSTRACT FROM AUTHOR]

In this paper, a systematic study was completed on the distribution features and origins of karst collapses in north China. There are 65 modern karst collapse areas with 1,416 karst collapse pits and 38 paleo–karst collapse areas with 3,654 paleo-collapse pillars. Modern karst collapses are mainly distributed in the plain region of the east Taihang and Yanshan Mountains and are concentrated in three zones from the west to the east in this region. The regional distribution features of karst collapses in north China are controlled by the boundary of the geological tectonics, condition of soluble rock and the extent of human activities. From the results, three-grade indices have been adopted to establish a classification scheme for karst collapse in north China. The effects of karst collapses on the environments in north China are summarized using a karst collapse classification scheme. [ABSTRACT FROM AUTHOR]

This paper investigates the economic costs of pollution due to sulphur dioxide emissions in China and their impacts on human health and ecosystems in Northeast Asia, specifically China and Japan. We compare actual emission charging as practiced in China with the estimated domestic and regional ‘optimal’ charges. The analysis demonstrates that, while the actual SO2 emission charge in China has been increased, it may be still less than the estimated domestic ‘optimal’ charge incorporating damage costs only on human health by dry deposition in a gaseous form, excluding damage costs caused by acid rain in China. Nevertheless, it would be still beneficial for Japan to financially assist China with its SO2 reduction because the percent contribution by northeast China to deposition in Japan is increasing. [ABSTRACT FROM AUTHOR]

The Yellow River is the second longest river in China and the cradle of the Chinese civilization. The source region of the Yellow River is the most important water holding area for the Yellow River, about 49.2% of the whole runoff comes from this region. However, for the special location, it is a region with most fragile eco-environment in China as well. Eco-environmental degradation in the source region of the Yellow River has been a very serious ecological and socially economic problem. According to census data, historical documents and climatic information, during the last half century, especially the last 30 years, great changes have taken place in the eco-environment of this region. Such changes are mainly manifested in the temporal-spatial changes of water environment, deglaciation, permafrost reduction, vegetation degeneracy and desertification extent, which led to land capacity decreasing and river disconnecting. At present, desertification of the region is showing an accelerating tendency. This paper analyzes the present status of eco-environment degradation in this region supported by GIS and RS, as well as field investigation and indoor analysis, based on knowledge, multi-source data is gathered and the classification is worked out, deals with their natural and anthropogenic causes, and points out that in the last half century the desertification and environmental degradation of this region are mainly attributed to human activities under the background of regional climate changes. To halt further degradation of the environment of this region, great efforts should be made to use land resources rationally, develop advantages animal agriculture and protect the natural grassland. [ABSTRACT FROM AUTHOR]

Lithium as an energy metal has gained significance in a wide range of application that spread across many industry sectors, along with its key role in emerging electric vehicles. China is a key use and producer of lithium and related products. In order to draw an entire picture of the lithium cycle, this study attempts to quantify the flows, stocks, and loss of lithium in the anthropogenic cycle in China, from 2007 to 2014. Substance Flow Analysis is employed in this paper for data mining and compilation. The results illustrate that production and use increased greatly from 2007 to 2014, due to the fast increase of the lithium ion battery. China’s lithium industry still heavily relied on the import of natural lithium ores, where lithium exports were mainly in the form of lithium ion battery-powered products, including laptop computers, mobile phones and electric bicycles. The stocks of lithium increased gradually from 2007 to 2014, but the loss of lithium from direct use also increased and more quickly. Therefore, the lithium stock in society cannot provide meaningful quantities as the second source for lithium production. It is suggested that the lithium in batteries should be recovered, as most lithium inputs are dispersed back into the environment, while the lithium industry still relies on imported lithium resources in China. [ABSTRACT FROM AUTHOR]

The Chinese Mitten Crab, a freshwater crab species originating from China, was accidentally introduced in Europe in the early 20th C when Western steamers, returning from China, emptied their ballast water tanks in German harbours. From there, in the course of the last century, the species gradually colonized the coastlines of the North Sea and the Atlantic southwards, but also much of the rest of the world. This visual essay is based upon material collected by Rotor for an installation at the 2018 Bruges Triennial. The narrative starts from the massive but scarcely known presence of the crab in the world-famed canals of the city of Bruges to tell the story of the species' amazing resilience and age-old adaptedness to anthropogenic environments. This is also a reconstruction of the Mitten Crab's unique travel patterns, partly the result of the species own migratory drive, but partly also following, unwittingly, the tendency of humans to travel ever further, ever faster. Like the exhibition, the essay explores the habits and motivations of an invasive species while deliberately suspending judgment. This is not to excuse the species of harming local biodiversity. But to recognize the fair share of responsibility we as humans bear in the present situation. [ABSTRACT FROM AUTHOR]

Water supply is strategic for the development of society. The water distribution in nature follows patterns linked to geographic and territorial issues. Climate fluctuations aggravate shortage problems in semi-arid regions. This study aims to develop a systematic review of research on water scarcity in semi-arid areas through bibliometric methods that allow the analysis of its structure, performance, evolution, and future trends. The methodology considers three phases: (i) literature review, (ii) data cleaning and processing, and (iii) analysis of the research field and future trends. The intellectual structure of water scarcity in semi-arid zones covers 2206 documents with the collaboration of sixty-one countries, distributed in studies carried out in 54 years (1967 to 2021). This field of research has been growing, especially since the 21st century (93.1% of the documents). The countries that study the issue the most are those with high population rates and large consumption patterns, such as the United States and China. There are two central areas of interest led by the terms "water scarcity" and "water stress" due to the intensive use of the resource for agriculture and the management of the water–energy–climate nexus. Thus, the most significant journals studied relate remote sensing to resource management, and the most cited are related to agriculture. This research made it possible to consider future topics such as the study of anthropogenic effects and climate change, the accuracy and applicability of models, and future trends in conventional and unconventional agriculture and resources. [ABSTRACT FROM AUTHOR]

Recently, more and more poisoning accidents associated with toxic heavy metals have been reported throughout China, coal-fired power plants (CFPPs) sector is regarded as one of the most important source categories of anthropogenic atmospheric releases of heavy metals due to tremendous annual coal consumption (about 1785.3 Mt in 2012). In this paper, with the concept of whole process control, the co-benefit or synergistic removal efficiencies of different control measures used in CFPPs of China are evaluated, the combination of coal washing before burning plus post combustion cleaning of selective catalytic reduction (SCR) + electrostatic precipitator/fabric filters (ESP/FFs) + wet flue gas desulfurization (WFGD) configuration is identified to be the best available control technology for heavy metals abatement of CFPPs at present and in the near future. However, the widely application of special mercury control (SMC) technologies in Chinese CFPPs in future is greatly needed. Furthermore, three energy scenarios and three control scenarios were assumed to forecast the future trend of heavy metals emissions. Under the same control scenario, the change of the energy saving and energy structure will give rise to about 24.1% and 24.6% of abatement potential for heavy metals in 2020 and 2030, respectively. Whereas, under the current energy consumption pattern and air pollution control policies, the installation of SCR + SMC + ESP/FFs + WFGD will result in about 21.0–44.1% and 36.3–67.5% of reduction for heavy metals emissions in 2020 and 2030, respectively. Finally, integrated control suggestions are proposed to minimize the final toxic heavy metals discharges. [ABSTRACT FROM AUTHOR]

This paper describes a novel approach to the evaluation of anthropogenic impacts on flood risks in coastal mega-cities by incorporating three anthropogenic variables (land subsidence, urbanization and flood defence) within a scenario-based framework where numerical modelling was undertaken to quantify the risks. The evolving risks at four time points (1979, 1990, 2000 and 2009) were assessed for the Huangpu River floodplain where the city of Shanghai is located. A 2D hydrodynamic model (FloodMap-Inertial) was used to estimate the flood risks associated with each scenario. Flood events with various return periods (10-, 100- and 1000-year) were designed based on a one in 50 year flood event that occurred in Shanghai on August 1997. Results demonstrate the individual as well as the combined impacts of the three anthropogenic factors on the changing fluvial flood risks in the Huangpu River basin over the last three decades during the city's transitional economy (1979–2009). Land subsidence and urbanization were found to lead to proportionate but non-linear impact on flood risks due to their complex spatial and temporal interaction. The impacts and their sensitivity are the function of the rate and spatial distribution of each evolving factor. While the pattern of response to individual anthropogenic variables is largely expected, the combined impacts demonstrate greater spatial and temporal variation. Flood defences offer considerable benefits in reducing the total inundated areas in the Huangpu River basin over the periods considered, for all magnitude floods. This, to a large extent, alleviates the adverse impacts arising from land subsidence and urbanization. [ABSTRACT FROM AUTHOR]

Mu Us Sandy Land (MUSL) in northern China as a typical eco-fragile region contains approximately one-third of the Chinese coal reserves. The region has a long history of coal mining with prolonged human-induced activities that might accompany aeolian desertification development. Since China started implementing the western development policy in 2000, the mining activity has expanded rapidly in the MUSL region and impacted strongly the sustainable socioeconomic development. Up till now, only scattered information on these activities is available from specific studies. In this paper, based on the Landsat TM, ETM, and OLI images from 2000, 2005, 2010, and 2013, we monitor systematically the expansion of coal mining activity using the mining regions as an indicator and the changes of the land cover type due to the expansion of mining activity in the MUSL region. Based on these data, we developed a database of mining region by introducing a mining region classification system and use it to discuss the spatial and temporal evolution trends of mining activity. The obtained results provide evidences for managers to evaluate the execution of government planning and the effect of rapidly expanded mining activity on the local ecological environment. [ABSTRACT FROM AUTHOR]

The farming-pastoral region of North China is a region that has suffered from serious desertification, and the multiple transitional characteristics in this region make it very difficult to link the progress of desertification to the driving forces behind it. This paper mainly focuses on the dynamics of desertification over the past 10 years and their relationship to climate change and human activity. According to the MODIS images in 2000 and 2010, the farming-pastoral region had experienced significant desertification dynamics over the past 10 years. The area of regions that had undergone desertification reversion and expansion were 186,240 km 2 and 199,525 km 2 respectively, and the spatial distribution of these regions showed great heterogeneity. The relationship between desertification dynamics and their driving forces was investigated by comparing the change in the NPP that was induced by climate change and human activity for each pixel that experienced desertification reversion and expansion. From 2000 to 2010, the coupling of climate change and human activity was the dominant factor behind desertification reversion. However, the human activity was the dominant factor that controlled the desertification expansion process between 2000 and 2010. The driving processes of desertification also had considerable spatial heterogeneity, and the dominant factors behind desertification reversion and expansion in each sub-region were not completely the same. So, the scale effect must be considered when explaining the results from similar studies. [ABSTRACT FROM AUTHOR]

Abstract: The identification of the relationships between different landscape services is important in social–ecological complex systems, especially in areas with intensive human activities. In this paper, Beijing and its peripheral regions are taken as a case study to calculate and map the intensities of five classic landscape services including material production, carbon storage, soil retention, habitat conservation, and population support based on grid maps. Overlap and correlation analyses were used to identify multiple service hotspots and the relationships between landscape services. The results show that (1) landscape services have spatial heterogeneity: high-intensity area of material production and population support is on the southeast plains of this region and high-intensity area of soil retention and habitat conservation is on the northwest; (2) approximately 96.03% of the region can provide at least one type of landscape services, whereas approximately three-quarters of the area provide multiple services, with the multiple service hotspots surrounding Beijing and Tianjin; (3) correlations exist between all pairs of landscape services, but strong correlations (correlation coefficient >0.5 or <−0.5) exist between four pairs, which are soil retention and habitat conservation (0.672), soil retention and population support (−0.613), habitat conservation and population support (−0.540), and material production and population support (0.529); (4) the services can be divided into two trade-off service bundles: the “natural” bundle, which contains carbon storage, soil retention, and habitat conservation, and the “artificial” bundle, which contains material production and population support. Only 4.19% of the area in this region contains these service bundles simultaneously. Finally, an improved understanding of the relationships between services was illustrated, and the importance of such services was highlighted for decision-makers and stakeholders. [Copyright &y& Elsevier]

The implementation of systemic modeling methods to understand the variation of natural capital and ecosystem services in response to economic activities has huge significance for sound decision-making also at local scale. This paper reports the results of an investigation performed on the grassland ecosystem in North Xinjiang. The Emergy Synthesis method introduced by H.T. Odum in the 1980s was used to dynamically simulate the trend of grassland natural capital and its related ecosystem services. The simulation of natural capital was based on indexes of standing biomass, soil organic matter, soil nitrogen and soil water storages; ecosystem services were assessed by means of indexes of annual CO2 uptake, O2 release, forage supply as animal feed, food supply for human nutrition, and finally soil conservation. Results indicate that an upper limit of livestock carrying capacity in the region was reached in the year 1994; after that year the natural capital and main ecosystem services of the grassland ecosystem declined steadily. The emergy based currency equivalent value of the grassland ecosystem in terms of ecosystem services was higher than 87.3 billion Yuan RMB/yr in 1990. Such a value declined to 62.3 billion Yuan RMB/yr in 2010. Similarly, the total emergy based value of natural capital was about 331.7 billion Yuan RMB in 1990 and dropped to 155.6 billion Yuan RMB in 2010. According to the simulation model, the natural capital components such as biomass and soil stocks, the ecosystem services and the replacement value declined due to intensive herding and disturbance from human activities. Such trend is not sustainable because it exceeds the renewable carrying capacity of the area, but it is likely to continue until fundamental changes in human behavior and management of the grassland and animal husbandry occur or until the whole area is fully degraded. Social reasons prevent from simply decreasing the intensity of the livestock activities that provide living means to a large number of local farmers. As a consequence, the traditional low-productivity and environmental unfriendly grazing farming system should gradually be converted into a human-managed pasture based on farming higher productivity pasture crops in a small part of the local land, in order to decrease the grazing pressure on natural grassland of North Xinjiang. [Copyright &y& Elsevier]

Abstract: Water discharge and sediment load have changed continuously during the last half century in the Yellow River basin, China. In the present paper, data from 7 river gauging stations and 175 meteorological stations are analyzed in order to estimate quantitatively the contributions of human activities and climate change to hydrological response. Coefficients of water discharge (C w ) and sediment load (C s ) are calculated for the baseline period of 1950s–1960s according to the correlations between the respective hydrological series and regional precipitation. Consequently, the natural water discharge and natural sediment load time series are reconstructed from 1960s–2008. Inter-annual impacts are then separated from the impacts of human activities and climate change on the hydrological response of different regions of the Yellow River basin. It is found that human activities have the greatest influence on changes to the hydrological series of water discharge and sediment load, no matter whether the effect is negative or positive. Moreover, the impact of human activities is considerably greater on water discharge than sediment load. During 1970–2008, climate change and human activities respectively contribute 17% and 83% to the reduction in water discharge, and 14% and 86% to the reduction in sediment yield in the Upper reaches of Yellow River basin; The corresponding relative contributions in the Middle reaches are 71% and 29% to reductions in water discharge, and 48% and 52% to reductions in sediment load. Moreover, it is observed that the impacts of human activities on the whole basin are enhanced with time. In the 2000s, the impact of human activities exceeds that of climate change in the 2000s, with human activities directly responsible for 55% and 54% of the reductions in water discharge and sediment load in the whole basin. [Copyright &y& Elsevier]