Guanzhong Area Research Articles

County-level carbon emissions in the guanzhong area of Shaanxi province: towards achieving China’s dual carbon goals

China’s rapid urbanization has significantly impacted carbon emissions in rural areas, driving the need for region-specific carbon management strategies to achieve the country’s dual carbon goals. However, previous research has primarily focused on large urban centers, leaving a gap in understanding the spatial and temporal patterns of carbon emissions at the county level in rural regions. This study focuses on the Guanzhong region of Shaanxi Province and develops a county-level carbon emission accounting system based on geographic, socio-economic, and land-use data. The carbon emissions are categorized into energy, industrial processes, agriculture, and waste management. Key findings indicate that industrial and residential sectors are the primary contributors to carbon emissions, with Xi’an being the largest emitter. Carbon emission intensity follows a ranking of Xi’an < Weinan < Baoji < Xianyang < Tongchuan. Spatial patterns show a “core-edge” distribution, with higher emissions in urban centers and lower emissions in rural areas. The study also highlights the carbon sink potential in the southern Qinling National Park. This research provides a valuable framework for rural low-carbon development and offers critical insights for policymakers aiming to balance carbon reduction and economic growth in rural China.

Research on the hydraulic response characteristics during the water conveyance process of water diversion projects

Abstract During the initial trial period, the Hanjiang-to-Weihe River Valley Water Diversion Project (HWRVWD) sourced water from the Sanhekou water conservancy junction. It then transferred water through the Qinling water conveyance tunnel and distributed it at the Huangchigou water distribution hub, ultimately transporting it to the Guanzhong area. The hydraulic simulation and real-time control of the water conveyance system play a crucial role in ensuring the safe and efficient operation of this engineering project. To maintain water transfer safety and reasonable scheduling during the water supply process, the hydraulic characteristics of the transient process were calculated and analyzed in this paper. The one-dimension (1D) hydrodynamic mathematical model and advection-dispersion model were established to calculate the hydraulic factors of the 81.78 km Qinling water conveyance tunnel and the Huangchigou water distribution hub within the HWRVWD. Validation results showed that the root mean squared error tended toward zero and the coefficient of determination exceeded 0.97 between the measured values and the simulated values. The opening of gates and upstream inflow directly affected water level variations and storage. Smaller gate openings led to increased water level amplitudes before the gate and faster reaching of maximum water levels, but it also led to opposite trends in flow rates behind the gate compared to upstream water levels. The impact of incoming water flow rates on flow variations at different channel sections was significant. The time for water heads to reach each section and the rate of flow variation positively correlated with incoming water flow rates. Gradual increases in upstream inflow resulted in progressively larger water level amplitudes both before and behind the gate, with an increased maximum value, but more water might be discarded. When the water demand changes, the primary focus is on controlling the upstream inflow, with gate opening adjustments as a secondary measure, to achieve the goal of minimizing or eliminating water wastage.

The subsistence strategy transformation of the Yangshao culture (6900-4800BP) in the Guanzhong Area and Western Henan based on new faunal materials from the Miaodigou site

While the significance of the Yangshao culture in early China is widely recognized, systematic and detailed analysis and discussion of its subsistence strategy are lacking, especially for faunal materials. This paper examines the new and crucial faunal remains that include 3,400 identified specimens from the Miaodigou site unearthed in 2002. At that site, pig husbandry was predominant and wild animals were occasionally hunted as supplemental resources. In combination with published research including zooarchaeology, paleoethnobotany, and carbon and nitrogen stable isotope studies of 29 other sites mainly from the Guanzhong area and western Henan, we argue that subsistence strategy underwent a comprehensive and profound transformation during the middle period of Yangshao culture, namely Miaodigou period, as crop production and pig husbandry flourished in a wide range of areas. Domestic pigs accounted for over 80% of mammals, reaching an unprecedented proportion in the Neolithic age and manifesting a high level of consistency in feeding and slaughtering, and foxtail millet replaced broomcorn to become the most important crop at all sites, both of which demonstrate the breadth and depth of this transformation. The tension between the deterioration of climate, the decrease of surrounding wildlife resources due to excessive development and the continuous growth of the population may have contributed to this transformation. This study enriches our understanding of human-environment interactions in the embryonic stage of Chinese civilization and triggers further thoughts on how culture, society, the environment and subsistence were entangled in the development of civilization.

Analysis of Roof Garden Plant Allocation and Its Benefits in Guanzhong Area under the Background of Human Settlement: A Case Study of Yangling Demonstration Area

Taking the Yangling demonstration area as the research object, this paper analyzes the local climate and combines the micro-environmental characteristics of rooftop gardens in Yangling to explore the principles of plant configuration in rooftop gardens. It selects suitable plants for rooftop gardens and investigates their ecological benefits in improving the urban heat island effect, reducing rainwater accumulation, and purifying the air, providing a reference for the construction and management of rooftop gardens in the Guanzhong region.

Thermal Comfort Research on the Rural Elderly in the Guanzhong Region: A Comparative Analysis Based on Age Stratification of Residential Environments

Addressing the thermal comfort of the elderly is a pressing concern amidst the escalating aging population in rural China. This study presents a comprehensive assessment of the thermal comfort within traditional and self-built dwellings in the Guanzhong region. Utilizing a mixed-methods approach encompassing both on-site measurements and questionnaire surveys, with a novel approach of segmenting the elderly population into three distinct age groups. The findings indicate that: (1) An average clothing thermal resistance of 1.83 clo among the elderly, which was found to be relatively higher when compared to other areas and positively correlated with age; (2) A thermal neutral temperature of 8.46 °C for traditional dwellings and 10.53 °C for self-built dwellings, both of which were lower than anticipated, indicating a discrepancy between current living conditions and elderly residents’ thermal expectations; (3) A positive correlation between age and the preferred neutral temperature, with the elderly showing a preference for warmer indoor environments. Additionally, we propose targeted strategies to enhance the thermal comfort of the elderly across different age groups and dwelling types. This study refines the thermal comfort evaluation system for the elderly in China’s cold climate regions, offering theoretical insights and practical guidance for the renovation of rural dwellings and the improvement of elderly living standards in the Guanzhong area.

The study on spatial distribution of water ecological environment carrying capacity during extreme drought conditions

Due to global warming and the disturbance of the interannual variability of precipitation, the frequency of extreme drought events has increased. The impact of global climate change on water resources is becoming increasingly apparent, then it is particularly necessary to explore the carrying capacity of water ecological environment under extreme drought conditions, which can guarantee the ecological water security in river basins. This study takes the Guanzhong area of the Wei River Basin as an example, calculating the water environment carrying capacity of 40 areas in the Weihe Guanzhong area in different levels of years under extreme drought conditions by comprehensive evaluation model of carrying capacity and using geographic information system GIS to display the spatial distribution of water environment carrying capacity in 40 regions. According to the results of the spatial distribution of water environmental bearing capacity, four different schemes are designed to improve the bearing capacity. The first plan reduces the industrial water consumption and irrigation quota by 5%, the second plan increases the industrial water and sewage treatment rate on this basis. the third plan further improves the development and utilization rate of surface and groundwater, and the fourth plan, on the basis of the first three plans, supplies 600 million cubic meters of industrial and agricultural water to Guanzhong region. Through comparative analysis, without taking any measures, under the extreme drought conditions, the water environment carrying capacity of the 40 areas in Guanzhong is all in an unbearable state. Overall, plan 4 has the most significant improvement in the water environment-carrying capacity, especially the Dong zhuang Reservoir of the Jing River which has played a very important role in enhancing the water ecological environment carrying capacity of the downstream water of the Wei River.

Determination on the thickness of superficially weathered layer of historical stones from Guanzhong area in China

Superficial weathering in the form of granular disaggregation, powdering and flaking on stone surface is one of the most serious damages to stone heritages, since the surface carries most of the artistic, historical information. The determination of the thickness of the superficially weathered layer of historical stones is critical to their conservation. However, the methodology for quantitative analyses of such thickness remains very limited. In this study, we carefully study the vapor absorption and pore structure evolution of historical sandstones from Guanzhong area with respect to their weathering. We find out that the thickness of superficial weathered layer of Guanzhong sandstones can be derived by following the changes in vapor absorption or pore structure. Such data achieved from various methods developed in this work are consistent with each other and in good agreement with the results obtained by using current techniques such as drilling resistance measurement, the Ruxton method and ultrasonic testing. Among all methods used, pore size distribution analysis requires less sample preparation and measures the thickness of superficial weathered layer of Guanzhong sandstones around 7 mm.

Responses of runoff and sediment yield to slope length and gravel content of Lou soil engineering accumulation slope in Guanzhong region, Northwest China.

With the economic development, a large number of engineering accumulation bodies with Lou soil as the main soil type were produced in Guanzhong area, Northwest China. We examined the characteristics of runoff and sediment yield of Lou soil accumulation bodies with earth (gravel content 0%) and earth-rock (gravel content 30%) under different rainfall intensities (1.0, 1.5, 2.0, 2.5 mm·min-1) and different slope lengths (3, 5, 6.5, 12 m) by the simulating rainfall method. The results showed that runoff rate was relatively stable when rainfall intensity was 1.0-1.5 mm·min-1, while runoff rate fluctuated obviously when rainfall intensity was 2.0-2.5 mm·min-1. The average runoff rate varied significantly across different rainfall intensities on the same slopes, and the difference of average runoff rate of the two slopes was significantly increased with rainfall intensity. Under the same rainfall intensity, the difference in runoff rate between the slope lengths of the earth-rock slope was more obvious than that of the earth slope. When the slope length was 3-6.5 m, flow velocity increased rapidly at first and then increased slowly or tended to be stable. When the slope length was 12 m, flow velocity increased significantly. In general, with the increases of rainfall intensity, inhibition effect of gravel on the average flow velocity was enhanced. When rainfall intensity was 2.5 mm·min-1, the maximum reduction in the average flow velocity of earth-rock slope was 61.5% lower than that of earth slope. When rainfall intensity was less than 2.0 mm·min-1, sediment yield rate showed a trend of gradual decline or stable change, while that under the other rainfall intensities showed a trend of rapid decline and then fluctuated sharply. The greater the rainfall intensity, the more obvious the fluctuation. There was a significant positive correlation between the average sediment yield rate and runoff parameters, with the runoff rate showing the best fitting effect. Among the factors, slope length had the highest contribution to runoff velocity and rainfall erosion, which was 51.8% and 35.5%, respectively. This study can provide scientific basis for soil and water erosion control of engineering accumulation in Lou soil areas.

Research on the Relationship between Jiannan West Jiedushi and Buddhism in the Mid to Late Tang Dynasty

This article comprehensively explores the relationship between Xichuan Jiedushi and Buddhism during the mid to late Tang Dynasty through a comprehensive investigation of internal and external classics, Buddhist relics, and field survey data, following the traditional cataloging method of seeking books based on categories and studying studies based on books. Jiedushi was not only the provincial governor during the middle and late Tang Dynasty, but also a synonym of a local administrative district. The predecessor of the Jiannan West Jiedushi, Jiannan Jiedushi, was one of the earliest Jiedushi established in the Tang Dynasty. Due to its developed economy and close proximity to the Guanzhong area, Jiannan West became an exceedingly important region of Tang Dynasty. Thus its significance was evident. At the same time, the flourishing of Buddhism in the Tang Dynasty reached its peak, affecting all fields. Under the influence of Buddhism, the bureaucrats and scholars generally worshipped Buddhism, among which included all the Jiannan West Jiedushi. In addition, under the bureaucratic system of Tang Dynasty, most Jiannan West Jiedushi were literary giants, which had significant influence on the formation and development of Chengdu's urban culture in the middle to late Tang Dynasty. Especially in religious activities, they extensively participated in the interaction between Confucianism and Buddhism, and treated famous monks with civility. And during their tenure, they either donated funds to build temples, or converted their residences into temples, or ordained people as monks. They fully supported the development of Buddhism, which not only united people in Jiannan West, but also indirectly stabilized the Tang Dynasty's rule of Jiannan West. This article comprehensively considers the background of the times, the intervention of political rights, the interaction of social classes, and the customs of life. At the same time, it refers to the influence of local officials represented by the Xichuan Jiedushi on religious philosophy, aesthetic psychology, cultural arts, sculpture, and other factors during this period, in order to objectively and comprehensively depict the Buddhism of Bashu in the middle and late Tang Dynasty.

Exploration and comparison of the relationship between PAHs and ROS in PM2.5 emitted from multiple anthropogenic sources in the Guanzhong Plain, China

Anthropogenic emissions have emerged as an important source of urban atmospheric PM2.5, exacerbating air pollution and the associated health implications. This study analyses PM2.5, originating from major anthropogenic sources (industries, motor vehicles, and solid-fuel combustion for domestic applications) in the Guanzhong Plain in China, along with the parent- (p-), alkylated- (a-), and oxygenated- (o-) polycyclic aromatic hydrocarbons (PAHs) and reactive oxygen species (ROS) levels in PM2.5. Industrial emissions are mainly characterised by high abundances of benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), and benz[a]fluoranthene (BaF). The 4-ring p-PAHs, such as fluoranthene (FLA), pyrene (PYR), benzo[a]anthracene (BaA), and chrysene (CHR) proportions and the diagnostic ratios of indeno[1,2,3-cd]pyrene (IcdP)/[IcdP + benzo[ghi]perylene (BghiP)] and 1-acenaphthenone (1ACO)/[1ACO + 9-fluorenone (9FO)] in motor vehicle emission PM2.5 were higher than the other sources. Household solid fuel combustion features high proportions of methylnaphthalene (M-NAP), i.e., 2 M-NAP and 1 M-NAP and 3-ring p-PAHs. Acenaphthylene (ACY), acenaphthene (ACE), anthracene (ANT), 1,4-chrysenequinone (1,4CHRQ), and reactive oxygen species (ROS) were positively correlated among the three anthropogenic sources. Moreover, the correlations between other PAHs and ROS varied significantly among the three sources. As mixed and compound organic pollutants, 2- and 3-ring p-PAHs were more positively correlated with the ROS activity of household solid fuel combustion sources compared with industrial and motor vehicle sources. Based on the relative contribution of these three sources to PAHs in PM2.5, we estimated the cancer risks of males and females in the Guanzhong area to be 2.95 × 10−6 and 2.87 × 10−6, respectively, exceeding the safety threshold of 1 × 10−6. This study provides a basic dataset for conducting a refined source apportionment of PM2.5 and a scientific basis for further understanding the relationship between PM2.5, PAHs, and ROS in northern China.

Staple food and possible famine food in Han Dynasty Guanzhong: Archeobotanical and stable isotopic perspectives

AbstractAgricultural yield fluctuations caused by environmental and social factors in ancient China have been well recorded in extensive ancient documents; however, comparatively little is known archaeologically. This study revealed the consumption and utilization of staple cereal and possible famine food by Han Dynasty inhabitants in the Guanzhong area based on archeobotanical evidence, including plant macro‐remains and phytoliths uncovered from pottery granaries and isotopic evidence from human bone collagen from Miaojiazhai cemetery. This preliminary multidisciplinary research with clear archaeological contexts provides archaeological evidence to reveal the food diversification and indicate that the possible occurrence and coping strategies to mitigate fluctuations in agricultural yields in Han Dynasty Guanzhong and broaden the understanding of the Han Dynasty agricultural economies and society.

Coupling effect analysis of drip irrigation and mixed slow-release nitrogen fertilizer on yield and physiological characteristics of winter wheat in Guanzhong area

ContextOptimising the management of water and fertilizer, and fully exploiting the positive effects of the coupling of water and fertilizer, are important ways of achieving high crop yields and promoting the sustainable development of water-efficient agriculture. ObjectiveThe objective of this study was to investigate the coupling effects of different irrigation levels and different mixing ratios of slow-release nitrogen fertilizers on the physiological growth characteristics and yield of winter wheat in Guanzhong region under drip irrigation. MethodsIn this study, field experiments were conducted in two winter wheat growing seasons, 2018–2019 and 2019–2020. The study included three irrigation levels: W1 (60% ETc, where ETc is the evapotranspiration of the crop), W2 (80% ETc), and W3 (100% ETc); and four N fertilizer treatments: U (100% urea), UNS1 (urea: slow-release N fertilizer = 1:1), UNS2 (urea: slow-release N fertilizer = 1:3) and SRF (100% slow-release N fertilizer). ResultsCompared to W1 and W2, W3 prolonged the winter wheat leaf functional period, increased leaf area index and net photosynthetic rate (Pn), and promoted dry matter accumulation. The total N content of winter wheat decreased by 22.67% and 9.93% under W1 and W2 conditions, respectively. The nitrogen use efficiency (NUE) decreased by 5.87% and 1.97%, respectively, leading to a decrease in yield. Slow-release nitrogen fertilizer (SRF) and its mixture treatments (UNS1, UNS2) increased post-flowering nitrogen uptake in winter wheat compared to U. At the same irrigation level, water use efficiency (WUE) was increased by 34.03%, 13.35%, and 20.86% in the UNS2 treatment compared to U, UNS1, and SRF, respectively. W3UNS2 obtained the highest grain yield: 8026.32 kg hm−2 (2018–2019) and 8993.25 (2019–2020) kg hm−2, with a 9.85–68.24% yield increase compared to other treatments. Und4er the treatments of this study, yield, WUE, and NUE of winter wheat reached 90% of the maximum at irrigation levels of 82.04–91.83% ETc and 59.18–83.67% of slow-release N fertilizer in blended fertilizer. ConclusionsUnder water stress conditions, UNS1 and UNS2 can mitigate the effects of water deficit on plant growth and stabilize grain yield. ImplicationsThis study provides useful information for optimising water and nitrogen management decisions for winter wheat in semi-arid climatic regions, and contributes to the promotion of sustainable development of wheat production and water-efficient agriculture.

Spatio-temporal variation of water requirement and meteorological impact factors of maize Shaanxi, China

To quantitatively reveal the characteristics of the spatial and temporal distribution and the influencing factors of the maize water requirement in Shaanxi Province, the Penman-Monteith model and path analysis were used to systematically analyze the interannual variation and spatial distribution of the maize water requirement at different growth stages in three climatic zones in Shaanxi Province. And the relationship between the water requirement and meteorological factors based on daily meteorological data in Shaanxi Province for the past 60 years. The results showed that the maize water requirement during the whole growth period decreased from 1960 to 1989, with a rate of change of −2.08 mm/a, increased from 1989 to 2019, with a rate of change of 0.38 mm/a, and decreased from 1960 to 2019, with a rate of change of −0.46 mm/a. The water requirement of maize decreases from north to south during the whole reproductive period. That of seedling and male stage are more in the Guanzhong, followed by the north and the least in the south. The water requirement of maize at jointing stage increased from north to south. And the water requirement distribution is more in the north, followed by the south and the least in the Guanzhong area during the maturity period. The average temperature and the duration of the sunshine are the key factors that affect maize water requirement in Shaanxi Province, and have an increasing effect on water requirement, wind speed has an increasing effect on water requirement but is not obvious, water vapor pressure and relative humidity have an inhibiting effect on water requirement. For spring maize, the promoting effect of the duration of the sunshine on maize water requirement was gradually strengthened from north to south. The promoting effect of mean temperature and wind speed decreased gradually. The inhibitory effect of water vapor pressure and relative humidity decreases continuously. This study can provide a scientific basis for the management of irrigation quota in maize growing areas under similar cropping conditions.

Estimation of Winter Wheat Plant Nitrogen Concentration from UAV Hyperspectral Remote Sensing Combined with Machine Learning Methods

Nitrogen is one of the most important macronutrients and plays an essential role in the growth and development of winter wheat. It is very crucial to diagnose the nitrogen status timely and accurately for applying a precision nitrogen management (PNM) strategy to the guidance of nitrogen fertilizer in the field. The main purpose of this study was to use three different prediction methods to evaluate winter wheat plant nitrogen concentration (PNC) at booting, heading, flowering, filling, and the whole growth stage in the Guanzhong area from unmanned aerial vehicle (UAV) hyperspectral imagery. These methods include (1) the parametric regression method; (2) linear nonparametric regression methods (stepwise multiple linear regression (SMLR) and partial least squares regression (PLSR)); and (3) machine learning methods (random forest regression (RFR), support vector machine regression (SVMR), and extreme learning machine regression (ELMR)). The purpose of this study was also to pay attention to the impact of different growth stages on the accuracy of the model. The results showed that compared with parametric regression and linear nonparametric regression, the machine learning regression method could evidently improve the estimation accuracy of winter wheat PNC, especially using SVMR and RFR, the training set of the model at flowering and filling stage explained 93% and 92% of the PNC variability respectively. The testing set of the model at flowering and filling stages explained 88% and 91% of the PNC variability, the root mean square error of the validation set (RMSEtesting) was 0.82 and 1.23, and the relative prediction deviation (RPD) was 2.58 and 2.40, respectively. Therefore, a conclusion was drawn that it was the best choice to estimate winter wheat PNC at the flowering and filling stage from UAV hyperspectral imagery. Using machine learning methods, SVMR and RFR, respectively, could achieve the most outstanding estimation performance, which could provide a theoretical basis for putting forward the PNM strategy.

Food, cooking and potteries in the Neolithic Mijiaya site, Guanzhong area, North China, revealed by multidisciplinary approach

Investigating the coevolutions in human food resources, cooking technologies and pottery functions will provide a vital perspective for understanding the driving force of social development in Neolithic China. Here, we preliminarily present a multianalytical study on the plant microfossils of pottery residues, the stable isotopic compositions and radiocarbon dating of animal bones, and the characteristics of pottery vessels (including their types, textures and smoked traces) from the Mijiaya site. The results indicate that the Mijiaya people (ca. 3093‒1961 cal. BC) probably relied on the various food resources consisting of the diversified crops, livestock and some foraging food; Mijiaya people had refined the pottery functions by changing their types, textures and assemblages, and they also used some auxiliary tools for increasing the cooking efficiency and obtaining the complex foodstuff. Integrated with agricultural development and technological innovation during Neolithic China, the foodways at the Mijiaya site also shed light on its inherited social tradition and social organization in the Late Neolithic period.

Assessing the Spatio-Temporal Dynamics of Land Use Carbon Emissions and Multiple Driving Factors in the Guanzhong Area of Shaanxi Province

Land use change is one of the key elements leading to carbon emission changes, and is of great significance to the process of achieving the goals of carbon peaking and carbon neutrality. In this study, we calculated the land-use carbon emissions (LCE) in the Guanzhong area (GZA) of Shaanxi province from 2000 to 2019 by using an improved LCE measurement model. Meanwhile, the spatial and temporal changes of LCE were analyzed and the driving forces were investigated based on the correlation analysis and multi-scale geographical weighting regression (MGWR). The results showed that the total amount of LCE showed a significant increasing trend from 2000 to 2019. Regions where the LCE significantly increased occupied 71.20% of the total area; these regions were distributed in the central and eastern parts of the study area. The LCE showed a significant positive spatial correlation and had a remarkable aggregation state. The H-H agglomeration area of LCE was distributed in the central urban agglomeration. The L-L agglomeration areas were always distributed in the southwest part of the GZA with low carbon emissions. The average correlation coefficients between LCE and nighttime light (NTL), population density (PD), and gross primary productivity (GPP) were 0.13, 0.21, and −0.05, respectively. The NLT and PD had obvious positive effects on LCE, while GPP has obvious negative effects on carbon emissions, which can be ascribed to the carbon sink effect of forests and grasslands. The results of this study have important reference value regarding the formulation of carbon emission reduction policies and the development of a low-carbon social economy.

Study on the Influence of Life Style on Constitution, Health and Disease of Residents in Guanzhong Area of Shaanxi Province

Study on the Influence of Life Style on Constitution, Health and Disease of Residents in Guanzhong Area of Shaanxi Province

Rapid Estimation of Decameter FPAR from Sentinel-2 Imagery on the Google Earth Engine

As a direct indicator of vegetation photosynthesis, the fraction of absorbed photosynthetically active radiation (FPAR) serves as a critical input in a series of land surface models. While existing satellite FPAR products are generally at coarse resolutions ranging from 250 m to 1 km, operational FPAR products at fine resolution are urgently needed in studying land surface processes at the plot scale. However, existing methods for estimating fine-resolution FPAR were mainly designed for Landsat data, and few studies have attempted to develop algorithms for Sentinel-2 data. In particular, the operational estimation of decameter FPAR has a higher requirement for the algorithms in terms of generalizability, efficiency, accuracy, and adaptability to Sentinel-2 data. In this paper, we developed a retrieval chain on the Google Earth Engine (GEE) platform to estimate FPAR by learning the relationship between MODIS FPAR and Sentinel-2 surface reflectance. Scale-consistent multilinear models were used to model the relationship between MODIS FPAR and Sentinel-2 surface reflectance, and the model coefficients were regressed from the selected training samples. To account for the spectral and spatial characteristics of the Sentinel-2 data, we designed criteria for selecting training samples and compared different band combinations. Three strategies for band combination were used: (1) green, red, and near infrared (NIR) bands at 10 m resolution (i.e., three bands); (2) green, red, NIR, and red edge (RE) 1, RE2, and RE3 bands at 20 m resolution (i.e., five bands); and (3) green, red, NIR, RE1, RE2, RE3, shortwave infrared1 (SWIR1) and SWIR2 bands at 20 m resolution (i.e., eight bands). Meanwhile, the official Sentinel Application Platform (SNAP) method has also been implemented to estimate the Sentinel FPAR at 10 m and 20 m resolutions for comparison. Both methods were applied to the western Guanzhong area, Shaanxi Province, China, for FPAR estimation of all cloud-free Sentinel-2 images in 2021. The results show that the scaling-based method using five bands at 20 m resolution was the most accurate compared to the in situ measurements (RMSE = 0.076 and R² = 0.626), which outperformed the SNAP method at 10 m and 20 m resolutions and the scaling-based method using other strategies. The results of the scaling-based method using all three strategies were highly consistent with the MODIS FPAR product, while the SNAP method systematically underestimated FPAR values compared to the MODIS FPAR products. The proposed method is more ready-to-use and more efficient than SNAP software. Considering that the service of the MODIS sensor is overdue, the proposed method can be extended to alternatives to MODIS products, such as VIIRS and Sentinel-3 data.

Aerosol Evolution and Influencing Factor Analysis during Haze Periods in the Guanzhong Area of China Based on Multi-Source Data

Aerosols suspended in the atmosphere negatively affect air quality and public health and promote global climate change. The Guanzhong area in China was selected as the study area. Air quality data from July 2018 to June 2021 were recorded daily, and 19 haze periods were selected for this study. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to simulate the air mass transport trajectory during this haze period to classify the formation process. The spatial distribution of the aerosol optical depth (AOD) was obtained by processing Moderate-resolution Imaging Spectroradiometer (MODIS) data using the dark target (DT) method. Three factors were used to analyze the AOD spatial distribution characteristics based on the perceptual hashing algorithm (PHA): GDP, population density, and topography. Correlations between aerosols and the wind direction, wind speed, and precipitation were analyzed using weather station data. The research results showed that the haze period in Guanzhong was mainly due to locally generated haze (94.7%). The spatial distribution factors are GDP, population density, and topography. The statistical results showed that wind direction mainly affected aerosol diffusion in Guanzhong, while wind speed (r = −0.63) and precipitation (r = −0.66) had a significant influence on aerosol accumulation and diffusion.

Climate Adaptability Analysis of Rural Housing in Guanzhong Region based on Climate Consultant

Energy conservation has been a hot issue contemporarily. Green building design needs to use computer technology to realize modeling and numerical simulation, which is an important method of building sustainable design. China has a vast territory, and the climate difference between different regions is significant, which also leads to the difference of building forms, structure and materials. This research analyzed the climate characteristics of Baoji through Climate consultant 6.0 software, and pointed out that Baoji is cold in winter and hot in summer, and its natural comfort time is short. Thus, it needs to be optimized through passive architectural design. At the same time, this research puts forward solutions to the climate adaptability of buildings, including expanding the southward window opening, introducing natural ventilation, improving the thermal insulation performance of the enclosure structure, and providing technical support for rural building energy conservation and rural revitalization in Guanzhong area.