29 research outputs found
Quantitatively assessing ecological stress of urbanization on natural ecosystems by using a landscape-adjacency index
Urban spatial expansion poses a threat to regional ecosystems and biodiversity directly through altering the size, shape, and interconnectivity of natural landscapes. Monitoring urban spatial expansion using traditional area-based metrics from remote sensing provides a feasible way to quantify this regional ecological stress. However, variation in landscape-adjacency relationships (i.e., the adjacency between individual landscape classes) caused by urban expansion is often overlooked. In this study, a novel edge-based index (landscape-adjacency index, LAdI) was proposed based on the spatial-adjacency relationship between landscape patches to measure the regional ecological stress of urban expansion on natural landscapes. Taking the entire Yangtze River Delta Urban Agglomerations (YRD) as a study area, we applied the LAdI for individual landscape classes (Vi) and landscape level (LV) to quantitatively assess change over time in the ecological stress of YRD from 1990 to 2015 at two spatial scales: municipal scale and 5 km-grid scale. The results showed that the vulnerable zones (LV ≥ 0.6) were mainly distributed in the north of the YRD, and cultivated land was the most vulnerable natural landscape (Vi ≥ 0.6) at the 5 km-grid scale. The most vulnerable landscape at the municipal scale was cultivated land in 19 of 26 cities in each period, and that in the remaining 7 cities varied at distinct urbanization stages. We used scatter diagrams and Pearson correlation analysis to compare the edge-based LAdI with an area-based index (percent of built-up area, PB) and found that: LV and PB had a significant positive correlation at both the municipal scale and 5 km-grid scale. But there were multiple LVs with different values corresponding to one PB with the same value at the 5 km-grid scale. Both indexes could represent the degree of urban expansion; however, the edge-based metric better quantified ecological stress under different urban-sprawl patterns sharing the same percent of built-up area. As changes in land use affect both the size and edge effect among landscape patches, the area-based PB and the edge-based LAdI should be applied together when assessing the ecological stress caused by urbanization
Greenspace’s value orientations of ecosystem service and socioeconomic service in China
Background: Natural ecosystems provide necessary services for human beings, including ecosystem service values (ESVs) and socioeconomic service values (SSVs). The value orientations of ESVs and SSVs are mainly related to people’s interaction with nature. This study reclassified greenspace from a perspective of exposed and non-exposed greenspace based on the level of interaction by people and greenspace. We applied an expert questionnaire to survey the SSVs value orientations of forestland, grassland, wetland, and water bodies, and quantitatively compared the value orientations between the ESVs and SSVs of greenspace in China. Result: (1) The values of exposed greenspace were relatively far higher than non-exposed greenspace, as it had both ESVs and SSVs. (2) The forestland and grassland had relatively high ESVs and SSVs, and are the priority for both the exposed and non-exposed greenspace. (3) Wetland had relatively high ESVs but low SSVs, which was unpopular for exposed greenspace. (4) The ESVs and SSVs of water body were relatively balanced. Conclusion: Greenspace had both ESVs and SSVs when they are exposed to human. Our study provided an innovative perspective to explore the value orientations of greenspace, which provides an actionable scientific basis for greenspace planning, design and construction in human habitat.
A Study on “Double-subject” Teaching Mode of Sport Statistics Course
Sport Statistics is an important applied subject in physical education field. Traditional teaching cannot meet its teaching demand. As a result, teachers are difficult in teaching and students are difficult in learning. Thus, it is very necessary to combine Sport Statistics with network teaching. In this study, the students of sports specialty were chosen as the objects of study, and “double-subject” teaching mode was used to teach Sport Statistics. Sport Statistics was combined with network course, and a new Web-based online courseware making platform system was applied. Besides, a network course quality evaluation model was constructed, and the evaluation was conducted from 7 aspects: teaching content U1, teaching design U2, course resource U3, page design U4, technical force U5, teacher as the subject U6 and user experience U7. It is found that “double-subject” teaching mode can significantly improve the teaching effect of Sport Statistics, motivate students’ learning interest, promote students’ oral expression ability, generalization and summarization ability, and self-learning ability, and enhance students’ ability to analyze and solve problems
Lower SO<sub>2</sub> Emissions in the Sintering Process Utilizing the Difference of Sulphur Contents of Iron Ores
Exploring the Relationship between the Spatial Distribution of Different Age Populations and Points of Interest (POI) in China
Population spatialization data is crucial to conducting scientific studies of coupled human–environment systems. Although significant progress has been made in population spatialization, the spatialization of different age populations is still weak. POI data with rich information have great potential to simulate the spatial distribution of different age populations, but the relationship between spatial distributions of POI and different age populations is still unclear, and whether it can be used as an auxiliary variable for the different age population spatialization remains to be explored. Therefore, this study collected and sorted out the number of different age populations and POIs in 2846 county-level administrative units of the Chinese mainland in 2010, divided the research data by region and city size, and explored the relationship between the different age populations and POIs. We found that there is a complex relationship between POI and different age populations. Firstly, there are positive, moderate-to-strong linear correlations between POI and population indicators. Secondly, POI has a different explanatory power for different age populations, and it has a higher explanatory power for the young and middle-aged population than the child and old population. Thirdly, the explanatory power of POI to different age populations is positively correlated with the urban economic development level. Finally, a small number of a certain kinds of POIs can be used to effectively simulate the spatial distributions of different age populations, which can improve the efficiency of obtaining spatialization data of different age populations and greatly save on costs. The study can provide data support for the precise spatialization of different age populations and inspire the spatialization of the other population attributes by POI in the future
Comparative Metabolomics Analysis of Cervicitis in Human Patients and a Phenol Mucilage-Induced Rat Model Using Liquid Chromatography Tandem Mass Spectrometry
Cervicitis is an exceedingly common gynecological disorder that puts women at high risk of sexually transmitted infections and induces a series of reproductive system diseases. This condition also has a significant impact on quality of life and is commonly misdiagnosed in clinical practice due to its complicated pathogenesis. In the present study, we performed non-targeted plasma metabolomics analysis of cervicitis in both plasma samples obtained from human patients and plasma samples from a phenol mucilage induced rat model of cervicitis, using ultra-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry. In addition to differences in histopathology, we identified differences in the metabolic profile between the cervicitis and control groups using unsupervised principal component analysis and orthogonal projections to latent structures discriminant analysis. These results demonstrated changes in plasma metabolites, with 27 and 22 potential endogenous markers identified in rat and human samples, respectively. The metabolic pathway analysis showed that linoleic acid, arachidonic acid, ether lipid, and glycerophospholipid metabolism are key metabolic pathways involved in cervicitis. This study showed the rat model was successfully created and applied to understand the pathogenesis of cervicitis
Long-Term Spatiotemporal Characteristics and Impact Factors of Land Surface Temperature of Inhabited Islands with Different Urbanization Levels
Surface thermal environment (STE) is closely related to the comfort and health of residents, affecting regional livability, and its spatial and temporal changes are deeply affected by the urbanization process. Considering there is a lack of effective comparative analysis on STE in different urbanized inhabited islands, the special geographical unit and vital human settlement environment, long-term spatiotemporal characteristics and impact factor quantitative analyses were performed in two inhabited islands via the RS and GIS methods. The results suggest that the surface heat amplitude of the highly urbanized Xiamen Island decreases, with the surface heat intensity continuing to increase from 2000 to 2020, while that of the lowly urbanized Kinmen Island is reversed. Although the land surface temperature (LST) of the two inhabited islands shows similar spatial distribution characteristics with evident cold/hot spots, the geographical distribution characteristics of high LST zones are significantly different, and the thermal landscape of Xiamen Island is more fragmented, discrete, and simple in shape, as revealed by the landscape metrics. We demonstrate that the area proportion between cooling land (water body and greenland) and warming land (bare land and impervious surface) is the most influential factor of LST in the two islands while the marine environment is a unique contributor to STE of inhabited islands compared with inland cities, where the seawater around the island can reduce LST over a range of distances, and the influence of elevation on LST is mostly indirect. These results provide a scientific basis and case support for understanding the STE situation of inhabited islands with different urbanization levels
Long-Term Spatiotemporal Characteristics and Impact Factors of Land Surface Temperature of Inhabited Islands with Different Urbanization Levels
Surface thermal environment (STE) is closely related to the comfort and health of residents, affecting regional livability, and its spatial and temporal changes are deeply affected by the urbanization process. Considering there is a lack of effective comparative analysis on STE in different urbanized inhabited islands, the special geographical unit and vital human settlement environment, long-term spatiotemporal characteristics and impact factor quantitative analyses were performed in two inhabited islands via the RS and GIS methods. The results suggest that the surface heat amplitude of the highly urbanized Xiamen Island decreases, with the surface heat intensity continuing to increase from 2000 to 2020, while that of the lowly urbanized Kinmen Island is reversed. Although the land surface temperature (LST) of the two inhabited islands shows similar spatial distribution characteristics with evident cold/hot spots, the geographical distribution characteristics of high LST zones are significantly different, and the thermal landscape of Xiamen Island is more fragmented, discrete, and simple in shape, as revealed by the landscape metrics. We demonstrate that the area proportion between cooling land (water body and greenland) and warming land (bare land and impervious surface) is the most influential factor of LST in the two islands while the marine environment is a unique contributor to STE of inhabited islands compared with inland cities, where the seawater around the island can reduce LST over a range of distances, and the influence of elevation on LST is mostly indirect. These results provide a scientific basis and case support for understanding the STE situation of inhabited islands with different urbanization levels
Spatial heterogeneity of vegetation phenology caused by urbanization in China based on remote sensing
Vegetation phenology changes caused by urbanization could lead to shifts in ecosystem services in urban areas and impact on human health. The characteristics of urbanization affect vegetation phenology need to be emphasized, especially in China with a complex natural environment and rapid urbanization background. In this study, we used remote sensing-based phenological data (MODIS MCD12Q2) to analyze the spatial heterogeneity of vegetation phenology caused by urbanization between urban and non-urban areas in 320 cities across China. We found a significant difference between vegetation phenology in urban and its corresponding non-urban area at national and the regional scale. For national scale, the start of the growing season (SOS) was significantly advanced by 2.53Â days (PÂ <Â 0.001), and the end of the growing season (EOS) was significantly delayed by 6.72Â days (PÂ <Â 0.001), resulting in the growing season length (GSL) was significantly extended by 9.25Â days (PÂ <Â 0.001). For regional scale, the changes of SOS, EOS, and GSL caused by urbanization varied from seven vegetation zones in China. As expected for the Tropical monsoon rain forest and rain forest zone (TR) and Tibetan plateau alpine vegetation zone (TP), and Warm-temperate broadleaf deciduous forest zone (WTB), vegetation phenology in other four vegetation zones shows significant differences between urban and non-urban areas. Furthermore, the potential factors driving phenological changes through urbanization were discussed, which will be of great help in understanding the urban ecological process in future studies