Search Results (10)

Traditional villages contain rich natural and humanistic information, and exploring the spatial distribution characteristics and cultural landscape zoning of traditional villages can provide scientific support for their centralized and continuous protection and renewal and sustainable development. In this study, 326 traditional villages in the northern Henan region were taken as the research object, followed by analyzing their spatial distribution characteristics by using geostatistical methods, such as nearest-neighbor index, imbalance index, geographic concentration index, etc., combining the theory of cultural landscape to construct the traditional villages’ cultural factor index system, extracting the cultural factors of the traditional villages to form a database, and adopting the K-means clustering method to divide the region. The results show that the spatial distribution of traditional villages in northern Henan tends to be concentrated overall, with an uneven distribution throughout the region. The density is highest in the northwestern part of Hebi City and lower in the central and southern parts of Xinxiang City, Neihuang County, and Puyang City. Based on the cultural factor index system, the K-means algorithm divides the traditional villages in northern Henan into six clusters. Among them, the five cultural factors of topography and geomorphology, building materials, courtyard form, structural system, and altitude and elevation are the most significant, and they are the cultural factors that dominate the landscape of the villages. There is a significant correlation between topography, altitude, and other cultural factors, while the correlation between the street layout and other factors is the lowest. Based on the similarity between the clustering results and the landscape characteristics, the traditional villages in northern Henan can be divided into the stone masonry building culture area along the Taihang Mountains, the brick and stone mixed building culture area in the low hills of the Taihang Mountains, the brick and wood building culture area in the North China Plain, and the raw soil building culture area in the transition zone of the Loess Plateau. Full article

Resource-depleted cities face challenges of land structure imbalance and ecological environmental degradation, necessitating relevant research. Clarifying the land use evolution path and exploring the rationality of urban expansion are of significant importance for the sustainable development of resource-depleted cities. This study employs a comprehensive approach utilizing the land use transfer matrix, expansion intensity, expansion speed, and the equal fan analysis method to investigate the evolution characteristics of construction land in Puyang, a typical resource-exhausted city in China, from 1990 to 2020. Additionally, it identifies the driving factors based on a comprehensive approach combining the variance inflation factor (VIF), grey relational analysis, and Pearson correlation analysis. The main findings include the following: (1) From 1990 to 2020, the cultivated land area in Puyang decreased by 181,296 hectares, while the newly added construction land amounted to 24,846.30 hectares, primarily converted from cultivated land. (2) Puyang comprises five counties and one district. Among them, Hualong District exhibited the highest expansion intensity, speed, and area, whereas Taiqian County showed the lowest. This disparity is attributed to resource-centered land development and utilization. (3) From 1990 to 2020, urban expansion in Puyang primarily concentrated in the northeast direction, exhibiting a concentric outward expansion pattern. (4) Socioeconomic factors positively influenced the expansion of construction land, with the “year-end total population” having the most significant impact. Conversely, land use and natural resource factors negatively impacted construction land expansion, with “cultivated land area” being the most prominent. Additionally, policy and institutional frameworks played a regulatory and restrictive role in the evolution of construction land, while topography and location served as fundamental conditions for urban expansion. This study provides methodologies for sustainable development research in resource-exhausted cities and offers a foundation for land use planning research in resource-based regions of China. Full article

Water security, as a crucial component of national security, plays a significant role in maintaining regional stability and ensuring the healthy and rapid development of the economy and society. The Yellow River water-receiving area of Henan Province (YRWAR-HN) is selected as the research area in this study. Firstly, a comprehensive evaluation index system is constructed based on the actual water security problems of the research area, and the single index quantification–multiple indices syntheses–poly-criteria integration method (SMI-P) is introduced to quantify the water security degree of 14 cities in the YRWAR-HN from 2010 to 2021. Then, the obstacle degree model is used to identify the key obstacle indexes that restrict the improvement of water security. Finally, the harmonious behavior set optimization method is adopted to carry out the regulation of water security, and the improvement path of water security in the YRWAR-HN is formulated. The results indicate the following: (1) the water security degree of the YRWAR-HN shows a fluctuating upward trend, increasing from 0.4348 (2010) to 0.6766 (2021), a significant rise of 55.61%. The water security level improves from the relatively unsafe level to the relatively safe level. Hebi City exhibits the fastest rate of water security improvement, while Xinxiang City shows the slowest rate. (2) The density of the river network (X1) and the proportion of investment in water conservancy and environmental protection in the total investment (X15) are the two indexes with the highest obstacle degree, with the average obstacle degrees being 15.09% and 10.79%, respectively. (3) The combination of the composite regulation scenario and improvement Path 2 is the optimal regulation strategy for water security in the YRWAR-HN. From the implementation process, Luoyang, Sanmenxia, Jiyuan, Xuchang, and Shangqiu may prioritize improving their flood and drought disaster defense capabilities and emergency response capabilities, continuously enhancing the flood prevention and disaster reduction system. Zhengzhou, Kaifeng, Xinxiang, Jiaozuo, Anyang, Hebi, Pingdingshan, and Zhoukou may prioritize resolving the regional water supply and demand conflicts, balancing development and conservation, actively seeking transboundary and external water transfers, and strengthening the capacity for water conservation and intensive utilization. Puyang City may prioritize enhancing its comprehensive water environment management capabilities, increasing investment in water conservancy and the environment, improving production processes, reducing pollutant emissions, and mitigating agricultural non-point source pollution. Full article

Ionic conductive hydrogels with good conductivity and biocompatibility have become one of the research highlights in the field of wearable flexible sensors and supercapacitors. In this work, poly(methacrylic acid–methyl methacrylate)-reinforced poly(sodium acrylate–vinyl phosphonic acid) composite hydrogels (P(AAS-VPA)/PMMS) were designed and tested for strain sensor or supercapacitor applications. The results showed recoverability for 20 cycles of tension and compression experiments, an excellent breaking strain of 2079%, and ionic conductivity of 0.045 S·cm⁻¹, demonstrating strong support for the application of the P(AAS-VPA)/PMMS hydrogel in strain sensors and supercapacitors. The composite hydrogel exhibited outstanding sensing and monitoring capability with high sensitivity (GF = 4.0). The supercapacitor based on the P(AAS-VPA)/PMMS composite hydrogel showed excellent capacitance performance (area capacitance 100.8 mF·cm⁻² and energy density 8.96 μWh·cm⁻²) at ambient temperature and even −30 °C (25.3 mF·cm⁻² and 2.25 μWh·cm⁻²). The hydrogel has stable electrochemical stability (1000 cycles, Coulomb efficiency > 97%) and exhibits electrochemical properties similar to those in the normal state under different deformations. The excellent results demonstrate the great potential of the P(AAS-VPA)/PMMS composite hydrogel in the field of strain sensors and flexible supercapacitors. Full article

Groundwater is closely related to hydrogeological structure and hydro-lithology, which mainly refers to the spatial distributions and properties of the environment where groundwater occurs. To analyze the constraints of hydrogeological structure and hydro-lithology on regional groundwater resources in the Eastern Henan Plain, China, we reconstructed the three-dimensional (3D) hierarchical models at two scales, hydrogeological structural models and hydro-lithological models, using hydrogeological cross-sections. First, the hydrogeological structural models of four aquifer groups, corresponding to four formations of the Quaternary in the study area, were reconstructed. Second, the hierarchical hydro-lithological model was built using SIS and IK estimation under the constraint of each aquifer group model space, respectively. Compared to global model, the variograms of hierarchical model captured more spatial characteristics of lithology in each aquifer group. The IK hierarchical model presents more continuities, clear boundaries, and realistic geometric shapes of the three lithologies, excluding the banding characteristics of the IK global model. The hierarchical SIS models reproduced the lithology distribution of each aquifer group and captured small changes in the lithology, with the smallest absolute percentage errors (APEs). Third, coupling the SIS hierarchical models and the groundwater levels, the groundwater resource in the study area was estimated to have a total volume of 1.2339 × 10⁴ m³. The shallow groundwater in the study area is mainly concentrated in Hebi City and the Puyang basin of the Yellow River, and deep groundwater is mainly concentrated in the northern Anyang City and Hebi City. Finally, the possible quantities of shallow and deep groundwater recharges were estimated for future groundwater management decision in the study area. The hierarchical hydrogeological model, groundwater resource assessment, and possible groundwater recharge estimation can also provide a basis for groundwater vulnerability, groundwater extraction, and land subsidence assessment. Full article

Landslides frequently occur along the eastern margin of the Tibetan Plateau, which poses a risk to the construction, maintenance, and transportation of the proposed Dujiangyan city to Siguniang Mountain (DS) railway, China. Therefore, four advanced machine learning models, namely, the Bayesian network (BN), decision table (DTable), radial basis function network (RBFN), and stochastic gradient descent (SGD), are proposed in this study to delineate landslide susceptibility zones. First, a landslide inventory map was randomly divided into 828 (75%) samples and 276 (25%) samples for training and validation, respectively. Second, the One-R technique was utilized to analyze the importance of 14 variables. Then, the prediction capability of the four models was validated and compared in terms of different statistical indices (accuracy (ACC) and Cohen’s kappa coefficient (k)) and the areas under the curve (AUC) in the receiver operating characteristic curve. The results showed that the SGD model performed best (AUC = 0.897, ACC = 80.98%, and k = 0.62), followed by the BN (AUC = 0.863, ACC = 78.80%, and k = 0.58), RBFN (AUC = 0.846, ACC = 77.36%, and k = 0.55), and DTable (AUC = 0.843, ACC = 76.45%, and k = 0.53) models. The susceptibility maps revealed that the DS railway segments from Puyang town to Dengsheng village are in high and very high-susceptibility zones. Full article

With the development of the human population and society, groundwater environmental problems have become an important factor limiting global socioeconomic development, and the study of groundwater hydrochemical characteristics and pollution is a current hot issue. In this study, data regarding shallow groundwater quality in 76 instances were used to evaluate the quality of shallow groundwater in the plains of Henan Province, China, by using a combination of subjective and objective assignments, mathematical statistics, Piper trilinear diagram, Gibbs diagram, ion ratio analysis, and other methods to study the hydrochemical characteristics of groundwater and its formation mechanism. The results showed that the groundwater quality in most areas of Henan Plain is in good condition, and the proportion of samples with excellent grades and good grades is as high as 43.42% and 35.53%. The range of poor and extremely poor water quality is small, and only five samples are judged as poor and extremely poor grades, mainly distributed in Jiaozuo City, Xinxiang City, Zhoukou City, and Puyang City. The groundwater anionic hydrochemistry is mainly of the HCO₃ type, accounting for 61.84% of the samples and locally transformed downstream to HCO₃·SO₄, HCO₃·SO₄·Cl, HCO₃·Cl·SO₄, and Cl·SO₄·HCO₃. Cations are predominantly of the Ca/Mg and Ca–Mg/Mg–Ca type, and gradually transformed to the Na–Ca/Ca–Na and Na–Mg/Mg–Na type along the runoff direction. Water–rock interactions and anthropogenic factors dominate the hydrochemistry evolution, with major geochemical processes involving the precipitation of calcite and dolomite as well as the weathering dissolution of rock salt and fluorite. Human activity is an important factor affecting the distribution of NO₃–N and Fe³⁺. It is recommended that groundwater be continuously monitored to provide scientific data for sustainable groundwater quality management and that appropriate measures be developed to prevent further degradation of the groundwater environment. Full article

Timely and accurate estimation of the winter wheat planting area and its spatial distribution is essential for the implementation of crop growth monitoring and yield estimation, and hence for the development of national agricultural production and food security. In remotely sensed winter wheat mapping based on spectral similarity, the reference curve is obtained by averaging multiple standard curves, which limits mapping accuracy. We propose a spectral reconstruction method based on singular value decomposition (SR-SVD) for winter wheat mapping based on the unique growth characteristics of crops. Using Sentinel-2 A/B satellite data, we tested the SR-SVD method in Puyang County, and Shenzhou City, China. Performance was increased, with the optimal overall accuracy and the Kappa of Puyang County and Shenzhou City were 99.52% and 0.99, and 98.26% and 0.97, respectively. We selected the spectral angle mapper (SAM) and Euclidean Distance (ED) as the similarity measures. Compared to spectral similarity methods, the SR-SVD method significantly improves mapping accuracy, as it avoids excessive extraction, can identify more detailed information, and is advantageous in distinguishing non-winter wheat pixels. Three commonly used supervised classification methods, support vector machine (SVM), maximum likelihood (ML), and minimum distance (MD) were used for comparison. Results indicate that SR-SVD has the highest mapping accuracy and greatly reduces the number of misidentified pixels. Therefore, the SR-SVD method can achieve high-precision crop mapping and provide technical support for monitoring regional crop planting structure information. Full article

Verticillium dahliae Kleb., the causal pathogen of vascular wilt, can seriously reduce the yield and quality of many crops, including cotton (Gossypium hirsutum). To control the harm caused by V. dahliae, considering the environmental pollution of chemical fungicides and their residues, the strategy of plant nutrition regulation is becoming increasingly important as an eco-friendly method for disease control. A new compound micronutrient fertilizer (CMF) found in our previous study could reduce the damage of cotton Verticillium wilt and increase yield. However, there is little information about the mode of action of CMF to control this disease. In the present study, we evaluated the role of CMF against V. dahliae and its mechanism of action in vitro and in vivo. In the laboratory tests, we observed that CMF could inhibit hyphal growth, microsclerotia germination, and reduce sporulation of V. dahliae. Further studies revealed that the biomass of V. dahliae in the root and hypocotyl of cotton seedlings treated with CMF were significantly reduced compared with the control, and these results could explain the decline in the disease index of cotton Verticillium wilt. Furthermore, those key genes involved in the phenylpropanoid metabolism pathway, resistance-related genes defense, and nitric oxide signaling pathway were induced in cotton root and hypocotyl tissue when treated with CMF. These results suggest that CMF is a multifaceted micronutrient fertilizer with roles in inhibiting the growth, development, and pathogenicity of V. dahliae and promoting cotton growth. Full article

The Beijing–Tianjin–Hebei (BTH) air pollution transmission channel and its surrounding areas are of importance to air pollution control in China. Based on daily data of air quality index (AQI) and air pollutants (PM_2.5, PM₁₀, SO₂, NO₂, CO, and O₃) from 2015 to 2016, this study analyzed the spatial and temporal characteristics of air pollution and influencing factors in Henan Province, a key region of the BTH air pollution transmission channel. The result showed that non-attainment days and NAQI were slightly improved at the provincial scale during the study period, whereas that in Hebi, Puyang, and Anyang became worse. PM_2.5 was the largest contributor to the air pollution in all cities based on the number of non-attainment days, but its mean frequency decreased by 21.62%, with the mean occurrence of O₃ doubled. The spatial distribution of NAQI presented a spatial agglomeration pattern, with high-high agglomeration area varying from Jiaozuo, Xinxiang, and Zhengzhou to Anyang and Hebi. In addition, the NAQI was negatively correlated with sunshine duration, temperature, relative humidity, wind speed, and positively to atmospheric pressure and relative humidity in all four clusters, whereas relationships between socioeconomic factors and NAQI differed among them. These findings highlight the need to establish and adjust regional joint prevention and control of air pollution as well as suggest that it is crucially important for implementing effective strategies for O₃ pollution control. Full article