Northern Areas Of China Research Articles

Applicability of the crop water stress index based on canopy–air temperature differences for monitoring water status in a cork oak plantation, northern China

The crop water stress index based on canopy–air temperature differences (CWSIdT) is an appropriate index for monitoring the water status of croplands but is rarely used to evaluate the water status of forest ecosystems. In this study, we selected a cork oak plantation in the lithoid mountain area of northern China as the research object and observed the canopy temperature (Tc), actual evapotranspiration (ETa), and meteorological factors of the plantation continuously and synchronously during the period of canopy closure (May–September) in 2020 and 2021. Taking the crop water stress index based on the ratio of ETa to potential evapotranspiration (CWSIet) as a standard, the applicability of CWSIdT for detecting water status in the plantation was evaluated. The results showed that, under well-watered conditions, the canopy–air temperature differences (dT) and the canopy surface transpiration rate were both controlled by the net radiation received by the canopy surface (Rnc), and the warming effect of Rnc masked the cooling effect of latent heat on dT, resulting in a failure establishment of the non-water-stressed baseline in the plantation. Therefore, the empirical CWSIdT (CWSIdTe) is not suitable for evaluating the water status in this plantation. However, the theoretical CWSIdT (CWSIdTt), based on the energy balance and Penman–Monteith equation, captured daily variations in the water status in our plantation and showed a significant linear correlation with the measured relative available water content in the root zone (R2 = 0.59, P < 0.01) and CWSIet (R2 = 0.75, P < 0.01). The CWSIdTt showed an upward trend during the day, and midday (13:00−14:00) was the optimal time to measure dT for detecting the daily water status of the plantation. The CWSIdTt provides an effective, sensitive, and non-contact method of assessing daily water status changes in the cork oak plantation.

Recycling, disposal, or biodegradable-alternative of polyethylene plastic film for agricultural mulching? A life cycle analysis of their environmental impacts

Plastic mulching is widely used in croplands to improve yields, while its mismanagement leads to plastic pollution in rural areas. China has explored different approaches to manage post-use plastic mulching, while there is still inadequate research regarding their corresponding environmental impacts. This study establishes five plastic mulching management scenarios, i.e., plastic mulching disposed of in nature, substituting biodegradable plastic, recycling, incineration, and landfilling, and maize cultivation in rural areas of northern China was taken as the studied case. We determine the comprehensive environmental impacts through a life cycle assessment (LCA) approach and completed a field investigation to obtain local datasets. The impurity content of used polyethylene mulching (PEM), an essential parameter for the entire life-cycle environmental impact assessment, is 80.1% ± 9.5%, examined by on-site sampling and scanning electron microscope. Results show that: 1) the use of biodegradable mulching (BM) instead of traditional PEM reduces carbon emissions by 22.6%; 2) the increment of soil carbon flux caused in the application stage is more significant than that in the post-use stage; 3) incineration of post-use mulch causes relatively significant photochemical oxidant formation effect; furthermore, recycling of plastic mulching leads to negative impacts in terms of human toxicity effect, meanwhile the positive environmental impact of fossil depletion effect is 2.3 times higher than that of incineration. Reducing the rate of impurity content in wasted plastic mulching can reduce transportation costs and promote sustainable plastic pollution management in rural areas.

Outbreak of occupational Brucella infection caused by live attenuated Brucella vaccine in a biological products company in Chongqing, China, 2020

ABSTRACT The northern areas of China are traditional endemic regions for brucellosis in both animals and humans, while occasional outbreaks of brucellosis have been observed in neglected southern provinces. On 16 December 2020, Chongqing Center for Disease Control and Prevention (CQCDC) received a report of 15 Brucella seropositive employees in a biological products company. The CQCDC and the local health administrative department launched an investigation that included identification of cases, laboratory testing of samples, and employees’ interview to identify the cause of this incident. A case-control study was implemented to compare high-risk factors between cases and serology-negative personals. Human and animal serum samples and environmental swabs were collected for testing. A total of 61 recessive infectors were found with an infection rate of 43.57% (61/140). Fisher’s exact test showed that there were significant differences in Brucella infection rates among different post classifications (p = 0.02), working places (p = 0.007), and buildings (p < 0.0001). Case-control study showed that working in vaccine production workshop was independently associated with an increased risk of infection (odds ratio (OR): 2.60; 95% confidence interval (CI): 1.31–5.19). The positive detection rate was 88.06% (59/67) for production environment and 16.67% (2/12) for external environment. The investigation indicated that close contact with biological products and aerosol were the potential transmission routes of this outbreak under the condition of insufficient personal protection and disinfection. Our study provides new epidemiological evidence for a more detailed understanding of occupational infections with live attenuated Brucella vaccine.

Optimizing Agricultural Input and Production for Different Types of at-Risk Peasant Households: An Empirical Study of Typical Counties in the Yimeng Mountain Area of Northern China.

Using typical counties in the Yimeng Mountain area of northern China as an example, this paper analyzed the household and agricultural input characteristics of different types of peasant households using survey data from 262 farm households. The target minimization of the total absolute deviations (MOTAD) model was applied to determine the optimal combinations in the allocation of agricultural input factors and production for different types of at-risk peasant households to obtain the ideal agricultural income. The relevant results are twofold. (1) The agricultural input behaviors of different types of peasant households vary significantly. The highest levels of agricultural land, labor, and yield-increasing and labor-saving inputs included I part-time peasant households (I PTPH), followed by full-time peasant households (FTPH), while the input levels of II part-time peasant households (II PTPH) and non-agricultural peasant households (NAPH) with higher levels of non-agricultural employment gradually decreased. In general, an increase in peasant households' part-time employment revealed an inverted U-shaped trend in the agricultural input level, with a trajectory of I PTPH > FTPH > II PTPH > NAPH. (2) The current agricultural inputs and production combinations of different types of peasant households have room for improvement. It is necessary to adjust agricultural inputs and optimize production combinations to obtain target incomes. Overall, all types of peasant households must streamline labor inputs and increase capital inputs, except for I PTPH, for which capital inputs should be reduced. Following optimization, economic crops gradually replace grain crops, and the optimal agricultural incomes of peasant households will be improved. The study results provide practical policy insights for reducing agricultural production risks and improving agricultural production incomes.

Water Storage and Use by Platycladus orientalis under Different Rainfall Conditions in the Rocky Mountainous Area of Northern China

Tree water transport and utilization are essential for maintaining ecosystem stability in seasonally arid areas. However, it is not clear how Platycladus orientalis absorbs, consumes via transpiration, and stores water under varying precipitation conditions. Therefore, this study used stem sap flow thermal dissipation probes and hydrogen and oxygen isotope tracing technology to observe different water control treatments in a P. orientalis plantation. We found that the average daily sap flow of P. orientalis under different water control treatments had the following order: no rainfall (NR) &lt; half rainfall (HR) &lt; double rainfall (DR) &lt; natural rainfall (AR). The percentage of nocturnal sap flow was as follows: AR (13.34%) &lt; NR (19.62%) &lt; DR (20.84%) &lt; HR (30.90%). The percentage of water storage was NR (4.13%) &lt; AR (4.49%) &lt; DR (6.75%) &lt; HR (9.29%). The sap flow of P. orientalis was primarily affected by vapor pressure deficit and solar radiation, with a degree of influence of DR &lt; NR &lt; HR &lt; AR. The response of P. orientalis sap flow to environmental factors differed due to the soil changes in relative extractable water (REW) before and after precipitation. During high REW conditions, environmental factors have a higher impact on sap flow. The source of water absorbed changed regularly with the precipitation gradient. When soil water content increased, the water source used by P. orientalis gradually changed to shallow soil. Compared to before and after precipitation, there was no significant change except for NR. P. orientalis could regularly adjust the activities of transpiration water consumption, water storage, and absorption. This adaptive property is conducive to survival through extreme drought stress.

A Seedbed Clearing and Shaping Device for Dry Direct-Seeded Rice

The soil in some areas of northern China is heavy owing to the presence of clay and stones, which significantly affects the normal operation of a planter as well as the growth of rice. In this regard, this study proposes a seedbed clearing and shaping device for dry direct-seeded rice, which can be used to remove stones in the seeding area, break soil blocks, for soil leveling, and groove forming. The overall structure and roller of the proposed device was developed based on theoretical calculations, discrete element modeling (DEM) simulations, and field tests. The soil-mixing tooth was distributed on the roller based on the double-helix rule, and the two sides of the helix were configured according to the right-hand and left-hand. Subsequently, DEM was used to develop a 33 box-bench design. According to the agronomic requirements and operating speed ratio, the forward speed was set to 0.5 m/s. Furthermore, the optimization parameters combination of the device obtained by simulation experiments was: forward speed 0.5 m/s, soil depth 61 mm, and rotation speed 110 r/min, which obtained a stone removal rate of 85.65%, stone removal efficiency of 35.47 pieces/m, operating resistance of 719.23 N, and torque of 174.89 Nm. The field verification test results indicated that the stone removal rate was 77.23% under the optimization parameters combination, and the mean relative error of the simulated experiments value was 8.42%, which showed that the performance of the proposed device functioned stably and reliably, thereby providing a high-quality seedbed for sowing and rice growth. The developed device represents a useful solution for the seedbed clearing and shaping.

Evolutionary game analysis of clean heating governance in rural areas of Northern China

The attainment of clean heating in the rural areas of northern China is of great significance for environmental governance and the realization of the dual carbon goal. Based on the evolutionary game theory, this study constructs a three-party evolutionary game model of the central government, local government, and farmers, introduces key parameters, such as the local government’s governance strength, central government’s inspection strength, and two levels of government subsidy strength, into the model, systematically deduces different possible strategy combinations of the three parties, and analyzes the possible scenarios and stability conditions of each scenario. Finally, the study numerically simulates each scenario and analyzes the influence of the key parameters on the strategies of the three parties. The study conclusions are as follows. 1) The system is optimized in Scenario 6 (1,1,0). 2) The strategy of the local government has a decisive influence on farmers, and the central government’s inspector strength has a weak effect on farmers. 3) The cost of clean heating over coal-fired heating has a significant effect on farm households but not on the two levels of government. 4) The low perception that farmers hold regarding the benefits of the indoor environment weakens the government’s subsidy effect. This study provides effective practical guidance and policy references for governments to promote clean heating in rural areas.

Distribution Characteristics and Formation Mechanisms of Highly Mineralized Groundwater in the Hetao Plain, Inner Mongolia

As the largest artesian irrigation area in northern China, the Hetao Plain is also one of the major grain-producing areas in China. Meanwhile, there is a large amount of highly mineralized groundwater resulting in the soil salinization and desertification in this region. In addition, this study also uses the traditional hydro-geochemical methods to investigate the spatial evolution characteristics and formation mechanisms of highly mineralized groundwater. The results indicate that there is a large amount of highly mineralized groundwater (salinity &gt; 3 g/L) in the shallow aquifer over the Hetao Plain. As far as the spatial patterns are concerned, there are significant spatial differences. In accordance with the structural, paleogeographic, landform, and hydrogeological conditions, the highly mineralized groundwater in the Hetao Plain can be divided into five zones, namely, the front fan depression, the north bank of the Yellow River, Xishanzui, Hasuhai in the Hubao Plain, and Dalad banner on the south bank of the Yellow River. Among them, the highly mineralized groundwater of Xishanzui exhibits the largest value of the salinity &gt; 10 g/L. The main cations are Mg2+ and Na+, while the main anions are Cl− and SO42−. Moreover, the groundwater in the highly mineralized area contains a large amount of I−. According to the analysis of Piper, Gibbs diagrams of groundwater, the proportion coefficients of various components and the indication of isotope, it can be seen that most of the chemical ions in groundwater in the highly mineralized zone come from evaporation-concentration, which are mainly affected by climate, sedimentary environment, hydrogeological conditions and hydrology. The source of high mineralization in Xishanzui are different from other high mineralization regions, and the highly mineralized groundwater in Xishanzui is formed by the infestation of deep underground salt brine. These results can provide scientific basis for the rational allocation of regional water resources and the promotion of water resources development and utilization.

Research on The Fusion of Ethnic Music and Culture in Northern China

This article believes that only the national art culture is a kind of art universally accepted by the world. If there is no nationality, it is like a tree without roots and a river without a source. Music culture is the same development law. This paper aims to study the fusion of ethnic minority music cultures in northern China to study the history and future of the inclusive culture of Chinese Han residents and various ethnic minorities in northern China. In the history of China for five thousand years, the origin of the music culture of ethnic minorities in the vast land area of northern China has shown a trend of cultural integration and diversified development. Furthermore, the integration of music culture among various ethnic minorities not only effectively promotes the development of music culture but also lays a solid foundation for the colorful music culture system of the Chinese nation. This paper mainly studies the fusion of ethnic minority music culture in northern China and tries to find an effective way to further inherit and promote the ethnic minority music culture in northern China.

Canopy Interception of Different Rainfall Patterns in the Rocky Mountain Areas of Northern China: An Application of the Revised Gash Model

Canopy interception is an important part of forest ecosystem hydrological processes. It is the first stage of water distribution when rainfall reaches the canopy and has an important impact on nutrient inputs and water exchange. Pinus tabulaeformis is a main tree species in the rocky mountain areas of Northern China, and it is also a primary species for artificial afforestation. In previous studies of canopy interception, applications of the revised Gash model did not take rainfall characteristics into account. Therefore, in this study, rainfall patterns were divided according to the local rainfall characteristics in the rocky mountainous areas of Northern China. Rainfall was divided into three patterns. Rain pattern A was the main rainfall type. Rainfall patterns B and C were two types of rainstorms. Next, the revised Gash model was used to simulate Pinus tabulaeformis plantations under different rainfall patterns. The results showed that the canopy interception rate of Pinus tabulaeformis plantations in this area ranged from 14.7% to 17.9%. The revised Gash model can be used to simulate Pinus tabulaeformis plantations in the rocky mountainous areas of Northern China, with good simulation results for more than 80% of the conventional rainfall patterns. Furthermore, the canopy interception effect of simulated cumulative rainfall events was better than the individual rainfall event. The simulation effect for special rainfall patterns was not good, so it is necessary to improve the model parameters or collect more rainfall samples. These results can be used to explore the applicability of the revised Gash model in Pinus tabulaeformis plantations in the rocky mountain areas of Northern China. They also demonstrate different applicability of the model under different rainfall characteristics.

Crop Identification and Analysis in Typical Cultivated Areas of Inner Mongolia with Single-Phase Sentinel-2 Images

The Hetao Plain and Xing’an League are the major cultivated areas and main grain-producing areas in Inner Mongolia, and their crop planting structure significantly affects the grain output and economic development in Northern China. Timely and accurate identification, extraction, and analysis of typical crops in Xing’an League and Hetao Plain can provide scientific guidance and decision support for crop planting structure research and food security in ecological barrier areas in Northern China. The pixel samples and the neighborhood information were fused to generate a spectral spatial dataset based on single-phase Sentinel-2 images. Skcnn_Tabnet, a typical crop remote sensing classification model, was built at the pixel scale by adding the channel attention mechanism, and the corn, sunflower, and rice in the Hetao Plain were quickly identified and studied. The results of this study suggest that the model exhibits high crop recognition ability, and the overall accuracy of the three crops is 0.9270, which is 0.1121, 0.1004, and 0.0874 higher than the Deeplabv3+, UNet, and RF methods, respectively. This study confirms the feasibility of the deep learning model in the application research of large-scale crop classification and mapping and provides a technical reference for achieving the automatic national crop census.

Associations of personal exposure to domestic heating and cooking fuel emissions and epidemiological effects on rural residents in the Fenwei Plain, China

Solid fuel combustion for domestic heating in northern China in the wintertime is of great environmental and health concern. This study assesses personal exposure to particulate matter with different aerodynamic diameters and multiple gaseous pollutants from 123 rural residents in Yuncheng, the Fenwei Plain. The subjects are divided into groups based on the unique energy source applied, including biomass, coal, and electricity/no heating activities. The health effects of the exposures are expressed with four urinary biomarkers. The personal exposure levels to three different aerodynamic particle sizes (i.e., PM10, PM2.5, and PM1) of the electricity/no heating group are 5.1 % –12 % lower than those of the coal group. In addition, the exposure levels are 25 %–40 % lower for carbon monoxide (CO) and 10.8 %–20.3 % lower for ozone (O3) in the electricity/no heating group than the other two fuel groups. C-reactive protein (CRP) in the urine of the participants in biomass and coal groups is significantly higher than that in the electricity/no heating group, consistent with the observations on other biomarkers. Increases in 8-hydroxy-2 deoxyguanosine (8-OHdG), interleukin-8 (IL-8), and vascular endothelial growth factor (VEGF) are observed for the exposures to higher concentrations of air pollutants. For instance, PMs and nitrogen dioxide (NO2) show significant impacts on positive correlations with 8-OHdG and IL-8, while O3 positively correlates with CRP. PM1 exhibits higher effects on the biomarkers than the gaseous pollutants, especially on VEGF and IL-8. The study indicates that excessive use of traditional domestic solid fuels could pose severe health effects on rural residents. The promotion of using clean energy is urgently needed in the rural areas of northern China.

Comprehensive understanding on sources of high levels of fine particulate nitro-aromatic compounds at a coastal rural area in northern China

Nitro-aromatic compounds (NACs) are among the major components of brown carbon (BrC) in the atmosphere, causing negative impacts on regional climate, air quality, and ecological health. Due to the extensive origins, it is still a challenge to figure out the contributions and originating regions for different sources of atmospheric NACs. Here, field observations on fine particulate NACs were conducted at a coastal rural area in Qingdao, China in the winter of 2018 and 2019. The mean total concentrations of fine particulate nitro-aromatic compounds were 125.0 ± 89.5 and 27.7 ± 21.1 ng/m3 in the winter of 2018 and 2019, respectively. Among the measured eleven NACs, nitrophenols and nitrocatechols were the most abundant species. Variation characteristics and correlation analysis showed that humidity and anthropogenic primary emissions had significant influences on the NAC abundances. In this study, two tracing methods of the improved spatial concentration weighted trajectory (SCWT) model and the receptor model of positive matrix factorization (PMF) were combined to comprehensively understand the origins of NACs in fine particles at coastal Qingdao. Four major sources were identified, including coal combustion, biomass burning, vehicle exhaust, and secondary formation. Surprisingly, coal combustion was responsible for about half of the observed nitro-aromatic compounds, followed by biomass burning (∼30%). The results by SCWT demonstrated that the coal combustion dominated NACs mainly originated from the Shandong peninsula and the areas to the north and southwest, while those dominated by biomass burning primarily came from local Qingdao and the areas to the west.

Performance Analysis of the Coupled Heating System of the Air-Source Heat Pump, the Energy Accumulator and the Water-Source Heat Pump

In the remote areas of northern China without central heating and gas supply, for users intending to replace coal-boilers, the air-source heat pump system is always questionable due to the contradiction between its heating capacity and user’s heating demand, especially in very cold areas, whose COP and economy is very poor. The accumulator with phase change materials would be a promising one to solve this problem. With the help of TRNSYS software, a heating system coupled with air-source heat pump, accumulator, and water-source heat pump and its operation mode are provided and analyzed based on the heat source renovation demand of a middle school in Tianshui City suburb which has 5560 m2 area to be heated. The average COP simulated during the heating period of the coupled heating system is 2.23. Based on the simulation model and results, the heat source renovation of the middle school in Tianshui City suburb was carried out, its tested and simulated COP over the day was 2 and 2.05, respectively, which also reveals the validity of the numerical method for this problem.

Modern Silicate Weathering Regimes Across China Revealed by Geochemical Records From Surface Soils

AbstractKnowledge of modern kinetically limited (i.e., silicate weathering depends on temperature and precipitation) and supply‐limited (i.e., weathering is limited mainly by the supply of fresh material) weathering regimes is important for analyzing the weathering–CO2–climate system on geological timescales. However, on the global scale, there are large knowledge gaps in modern silicate weathering regimes and their possible shifts, due to the lack of spatial information on in situ weathering processes. Here, we present the first detailed compilation of the major element concentrations in bulk and fine fraction (&lt;2 μm) samples of surface soils from across China, which we use to investigate modern silicate weathering regimes across China and possible shifts between regimes induced by tectonic uplift and climate changes. The results show that changes in climatic factors, especially precipitation, exert a first‐order control on spatial variations in silicate weathering intensity (expressed by the chemical index of alteration, CIA), with additional contributions from nonclimatic factors. Comparison of silicate weathering regimes with the CIA suggests that for bulk samples the supply‐limited weathering regime prevails in areas with CIA &gt; 80, and the kinetically limited regime prevails in areas with CIA &lt; 80. A significant inference from the results is that tectonic uplift and global warming could cause shifts between supply‐limited and kinetically limited weathering regimes in the active mountain belts and floodplains of southern China and in areas dominated by intermediate chemical weathering. However, no shifts would occur in some of the arid to extremely arid areas of northern China and in highland areas with extreme chemical weathering.

Residential greenness attenuated association of long-term air pollution exposure with elevated blood pressure: Findings from polluted areas in Northern China.

BackgroundEvidence on the hypertensive effects of long-term air pollutants exposure are mixed, and the joint hypertensive effects of air pollutants are also unclear. Sparse evidence exists regarding the modifying role of residential greenness in such effects.MethodsA cross-sectional study was conducted in typically air-polluted areas in northern China. Particulate matter with diameter < 1 μm (PM1), particulate matter with diameter < 2.5 μm (PM2.5), particulate matter with diameter < 10 μm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O3) were predicted by space–time extremely randomized trees model. We used the Normalized Difference Vegetation Index (NDVI) to reflect residential green space. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were examined. We also calculated the pulse pressure (PP) and mean arterial pressure (MAP). Generalized additive model and quantile g-computation were, respectively, conducted to investigate individual and joint effects of air pollutants on blood pressure. Furthermore, beneficial effect of NDVI and its modification effect were explored.ResultsLong-term air pollutants exposure was associated with elevated DBP and MAP. Specifically, we found a 10-μg/m3 increase in PM2.5, PM10, and SO2 were associated with 2.36% (95% CI: 0.97, 3.76), 1.51% (95% CI: 0.70, 2.34), and 3.54% (95% CI: 1.55, 5.56) increase in DBP; a 10-μg/m3 increase in PM2.5, PM10, and SO2 were associated with 1.84% (95% CI: 0.74, 2.96), 1.17% (95% CI: 0.52, 1.83), and 2.43% (95% CI: 0.71, 4.18) increase in MAP. Air pollutants mixture (one quantile increase) was positively associated with increased values of DBP (8.22%, 95% CI: 5.49, 11.02) and MAP (4.15%, 95% CI: 2.05, 6.30), respectively. These identified harmful effect of air pollutants mainly occurred among these lived with low NDVI values. And participants aged ≥50 years were more susceptible to the harmful effect of PM2.5 and PM10 compared to younger adults.ConclusionsOur study indicated the harmful effect of long-term exposure to air pollutants and these effects may be modified by living within higher green space place. These evidence suggest increasing residential greenness and air pollution control may have simultaneous effect on decreasing the risk of hypertension.

Hydrogeochemical Processes and Connection of Multi-Layer Groundwater System in Sunan Mining Area, Eastern China.

Groundwater is an important freshwater resource in the world and serves as the main source of water for mining areas in Northern China. Coal mining may cause changes in water quality. As such, to identify ways to prevent water contamination, this study investigates the hydrogeochemical processes and transport paths of a complex aquifer system in the Sunan mining area in Northern China. Using the APFS-MLR model, a geographic information system (GIS) spatial analysis, and a hydrochemical correlation analysis method, this study identifies the potential mineral phases in groundwater, the spatial distribution of mineral reactions, and the contribution rate of these reactions to hydrochemical variables. Inverse modeling is used to verify hydrogeochemical process. The study reveals the relationship between multiple aquifers and four hydrological transport paths. Here, Path 1 and Path 2 show that the Quaternary aquifer, Carboniferous aquifer, and Ordovician aquifer are recharging the Permian aquifer through mineral dissolution and precipitation, cation exchange, and sulfate reduction. On the other hand, Path 3 and Path 4 show that tthe connections of Carboniferous and Ordovician limestone aquifers are dominated by the dissolution and precipitation of minerals and cation exchange, and that they are mainly recharged by the Quaternary aquifer. In the future, the water level of the Permian aquifer may rise somewhat after mining ends, and the mixing of water from the Permian aquifer, Quaternary aquifer, Carboniferous aquifer, and Ordovician aquifer could cause cross-pollution. In addition, sewage produced by human activities may recharge the deep water through the shallow water, polluting the deep karst water. As such, measures should be taken to reduce the hydraulic connection between Permian mine water and karst aquifers. The results of this study may benefit water quality predictions and treatment approaches in other complex multi-layer aquifer areas in the world.

An analysis of multiple ecosystem services in a large-scale urbanized area of northern China based on the food-energy-water integrative framework

A better understanding of urban sustainability would be accomplished if the food-energy-water (FEW) relationship was linked with the system of multiple ecosystem services (ESs); however, the two systems have thus far been studied intensively but separately. Here, an analytical framework is developed from the perspective of the FEW interactions to investigate the dynamics of multiple ESs and its stressors. The main steps include 1) selecting ES and FEW indicators according to the socionatural features; 2) studying the spatiotemporal dynamics by a synergy and trade-off analysis and ES bundles; and 3) applying the random forest algorithm to identify the key stressors. The framework is applied to the state-level Hohhot-Baotou-Ordos-Yulin urban agglomeration, which consists of 4 cities and 38 counties in northern China, from 1991 to 2015 (5 years as a period). The results indicate that ESs with the food supply have increased while certain ESs have declined in some counties (e.g., Tumd Zuoqi, and Junggar). The trade-offs have increased from 5 to 11 pairs since 1996, and most of them were related to provisioning ESs. The bundles for water supply and conservation have shrunk, whereas the bundles for food supply have expanded. Agriculture and animal husbandry, which account for 71.58–83% of the total water consumption, have always been the most important stressors. Coal mining and thermal power generation were the important stressors from 2011 to 2015. The findings indicate that ESs should be considered constraining variables in FEW-related policy formulations.

Probabilistic potential health risk quantification, hydrochemistry, driving forces of groundwater nitrate and fluoride in a typical irrigation district, Northern China

Groundwater is the foremost water source of agricultural irrigation areas in northern China. However, the problem from excessive geogenic fluoride and anthropogenic nitrate in groundwater and its potential health risks are often neglected. This paper aims to identify the health threats, water quality and hydrochemistry in Weibei Plain, northern China. A total of 50 water samples collected in May 2021 were assessed by hydrogeochemical analysis, the entropy weight water quality index method and probabilistic human health risk assessment based on Monte Carlo stochastic simulation. The results showed that the hydrochemical type of surface water and groundwater was mainly SO4·Cl–Ca·Mg type. The rock weathering and cation exchanges were found to the important processes influencing hydrochemistry. The quality of surface water was higher than that of groundwater, with Class IV and Class V groundwater samples concentrated in the northwest of the study area. The F− concentration in groundwater samples generally exceeded the drinking water standard, which mainly came from mineral dissolution affected by excessive irrigation. Nitrate pollution in groundwater has regional characteristics, mainly from agricultural activities. Long−term use of groundwater might bring risks to residents' health, because more than 65% and 23% of groundwater samples exceeded the acceptable non−carcinogenic risk limits of F− and NO3− to children, respectively. Considering the uncertainty of model parameters, children will have a probability of more than 46.9% and 12.6% to face F− and NO3− risks in groundwater. Compared with NO3−, the high concentration of F− in groundwater posed a higher threat to human health, and children faced higher risks. Compared with the deterministic method, the stochastic simulation can more accurately reflect health risks. The findings of this study can help policymakers devise strategies to ensure a safe supply of domestic water.

The effect, mechanism, and heterogeneity of grassland rental on herders' livestock production technical efficiency: evidence from pastoral areas in Northern China

The effect, mechanism, and heterogeneity of grassland rental on herders' livestock production technical efficiency: evidence from pastoral areas in Northern China