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The coordinated development of rural infrastructure and ecological environment is an effective way to improve agricultural productivity. The primary focus of the current research is how the two can work together to promote regional economic development in rural areas and in related fields. This study takes the western region as the research object, constructs an evaluation index system for rural infrastructure and ecological environment, and uses the Min-max Scaling method, coupling coordination model, gray GM (1, 1) model, and standard deviation elliptical model for evaluation. The trends and driving factors for the coordinated development of rural infrastructure and ecological coupling in the region from 2012 to 2021 are analyzed. The main results are as follows: (1) Except for Tibet, Qinghai, and Ningxia, the coupling degree of rural infrastructure and the ecological environment in western China reached the maximum level during the research period, also the coordination degree showed a gradual upward trend. (2) A prediction for the development and evolution of rural infrastructure and the ecological environment in western China indicates a trend of agglomerative development in the southern region. (3) By strengthening the construction of reservoirs, improving sanitary conditions, improving cultivated land use area and forest coverage, and controlling soil erosion, the coordinated development of the two can be effectively promoted. The purpose of this study is to promote the sustainable and coordinated development of rural infrastructure and ecological environment, and to provide a reference for policy formulation in the relevant sectors and other countries and regions with similar situations. [ABSTRACT FROM AUTHOR]

Due to global warming and other climate changes, it is increasingly important to study the response of regional environmental changes and dynamic changes in vegetation to climate change. Based on meteorological data from the last 60 years, this paper calculates the humidity index of western China under a wide range of long time series in different regions and explores the cross-correlation effect between series by offering a comparison with NDVI data, to analyze the cross-correlation between wet and dry changes and changes in vegetation in western China on a spatial scale. The results show that the spatial distribution of the interdecadal humidity index is different between different regions in western China. For example, the semi-arid and the semi-humid zones of the Weihe River region exhibit significant changes, while the Xinjiang and Qinghai–Tibet regions show a trend of constant wetness, on the whole, and the Sichuan and Yunnan–Guizhou regions are relatively humid and the distribution of wetness and dryness is relatively stable. The distribution of high and low values of the humidity index is very obvious and consistent with that of the distribution of desert bare land and precipitation in western China. In common with the distribution in the humidity index, the maximum correlation number between the NDVI and the humidity index in the whole western region is also significantly different in spatial distribution. There is a positive correlation between the NDVI and the humidity index in 99% of the study area. However, the delay in response time of the NDVI to changes in the humidity index in each region is inconsistent. For example, changes in the NDVI lag changes in the humidity index in the Menggan region by generally either 2 months or 5 months, while in the Sichuan region the delay in response time is generally 3 months. The variation and trend in dry and wet areas are closely related to the geographical location, climate zone, and topographic terrain, which may be the reason for the differences in the distribution of vegetation types and the response time to dry and wet changes. There is significant interaction between the humidity index and the vegetation type or precipitation distribution in western China. The positive correlation between the NDVI and the humidity index means that the positive effect is more sensitive, and the response of grassland is the most sensitive in the ecosystem. [ABSTRACT FROM AUTHOR]

Currently, China has entered the development stage of a "low birth rate" demographically. There is a huge contradiction between the unbalanced and inadequate distribution of preschool education facilities (PEFs) and the people's expectations for "full and good education for children". This study took the Lingui New District, a typical new urban area in West China as the research area, and through the introduction of POI big data and GIS analysis methods, supplemented by GeoDA Bivariate Moran index analyses, established a kindergarten spatial database. The study found that preschool education facilities have problems such as insufficient quantity, uneven quality, low service coverage, poor accessibility, etc. Therefore, it is suggested to increase the proportion of public affordable preschool education facilities including kindergartens and nurseries, optimize the spatial distribution of preschool education, and improve the accessibility of preschool services to promote affordable, safe, and high-quality development of preschool education and to provide reference suggestions for the revision of relevant standards and the adjustment of the layout of preschool education in undeveloped regions of China. [ABSTRACT FROM AUTHOR]

Given that glaciers are good indicators of climate change, it is of great scientific significance to study glacier change for regional environmental protection and water resource development and utilization. Using the Google Earth Engine (GEE) platform, we obtained the distribution of glaciers in western China in 2000, 2005, 2010, 2015, and 2020. Then, we analyzed the temporal and spatial evolutions of the glacier areas and their responses to climate change. The results showed that there were 52,384 glaciers in western China in 2020, with an area of 42,903.57 km2, among which those belonging to the headwater of the Tarim River are the largest, accounting for 35.25% of the total area. From 2000 to 2020, the glaciers indicated an overall trend of retreat, with the total area decreasing by 15,575.94 km2 at a change rate of 1.46%/a. From 2000 to 2010, glaciers in the southeast Qinghai-Tibet Plateau (QTP) and Qilian Mountains saw the fastest area loss (>4%/a), followed by the Tianshan Mountains (3.31%/a), while those in the Pamir-Karakoram-West Kunlun regions and the Qiangtang Plateau had the slowest loss. From 2010 to 2020, the glacier retreat rate exhibited an accelerating trend in southeast QTP and the western Himalayas, while it slowed down in the Tianshan Mountains. The change in glaciers was greatly attributed to the combination of snowfall and summer temperature trends. The glaciers in southeast QTP showed an accelerated retreat tendency, probably due to the accelerating snowfall decrease and continuous temperature rise. The decreasing temperature mitigated the loss of glacier area in the Pamir-Karakoram-West Kunlun regions with continuously decreasing snowfall. [ABSTRACT FROM AUTHOR]

Since the implementation of the great western development strategy in 2000, the ecological environment in the western region of China has been significantly improved. In order to explore the temporal and spatial characteristics of vegetation coverage in the western region, this paper adopted the method of Maximum Value Composite (MVC) to obtain the mean Normalized Difference Vegetation Index (NDVI) of vegetation on the basis of the Moderate-resolution Imaging Spector audiometer (MODIS) data of 2000/2005/2010/2015/2018. Thereafter, the spatio-temporal differentiation characteristics of vegetation in western China were analyzed. The results show that: (1) According to the time characteristics of vegetation coverage in the western region, the average annual NDVI value of vegetation coverage in the growing season in the western region fluctuated between 0.12 and 0.15, among which that of 2000 to 2010 fluctuated more greatly but did not show obvious change trend. (2) Based on Sen trend and Mann-Kendall test analysis, the area of vegetation coverage improvement in the western region from 2000 to 2018 was larger than that of significant vegetation degradation. (3) From the perspective of global autocorrelation coefficient, Moran's I values were all positive from 2000 to 2018, which indicates that the vegetation coverage in the west showed strong positive autocorrelation in each period. According to the average value and coefficient of variation of vegetation coverage, the vegetation coverage was lower in 2000, its internal variation was smaller, and the vegetation coverage increased with time. According to the local spatial autocorrelation analysis, the vegetation coverage levels in different regions varied greatly. (4) The standard deviation ellipse method was used to study the spatial distribution and directional transformation of vegetation. It makes the result more intuitive, and the three levels of gravity center shift, direction shift, and angle shift were considered: the vegetation growth condition in the spatial aggregation area improved in 2015; the standard deviation ellipses in 2000 and 2018 overlapped and shifted eastward, which indicates that the vegetation coverage conditions in the two years were similar and got ameliorated. [ABSTRACT FROM AUTHOR]

Hydrological nonstationarity has brought great challenges to the reliable application of conceptual hydrological models with time-invariant parameters. To cope with this, approaches have been proposed to consider time-varying model parameters, which can evolve in accordance with climate and watershed conditions. However, the temporal transferability of the time-varying parameter was rarely investigated. This paper aims to investigate the predictive ability and robustness of a hydrological model with time-varying parameter under changing environments. The conceptual hydrological model GR4J (Génie Rural à 4 paramètres Journalier) with only four parameters was chosen and the sensitive parameters were treated as functions of several external covariates that represent the variation of climate and watershed conditions. The investigation was carried out in Weihe Basin and Tuojiang Basin of Western China in the period from 1981 to 2010. Several sub-periods with different climate and watershed conditions were set up to test the temporal parameter transferability of the original GR4J model and the GR4J model with time-varying parameters. The results showed that the performance of streamflow simulation was improved when applying the time-varying parameters. Furthermore, in a series of split-sample tests, the GR4J model with time-varying parameters outperformed the original GR4J model by improving the model robustness. Further studies focus on more diversified model structures and watersheds conditions are necessary to verify the superiority of applying time-varying parameters. [ABSTRACT FROM AUTHOR]

Policies directly affect land-use change, which in turn, affects ecosystem services. In parallel with the implementation of a full-scale development program for the western region, the Chinese government has introduced a series of ecological protection and restoration strategies for development and construction. This study conducted a quantitative spatial evaluation of the ecosystem service value (ESV) of national nature reserves in the western region under this dual policy of development and protection. On the basis of land-use data and related evaluation parameters, fluctuations in the valuation of ecosystem services during 2000–2010 were analyzed in response to land-use changes under the comprehensive policy. Results showed that the increases in the areas of forestland and water bodies led to an increase of CNY 74.1 billion in the ESV from 2000 to 2010, equivalent to 2.02%. Grassland with increased production capacity and water bodies were the main factors driving the total ESV dynamics. Values of all ES increased significantly. Therefore, the ecological conservation and restoration policy, along with the development policy, had a positive influence on ecosystem services in the nature reserves in western China. [ABSTRACT FROM AUTHOR]

Positive degree-day (PDD) indicates the accumulated positive temperature in a given time period; it directly relates to the melting of snow and ice, and it is a key parameter between global warming and cryosphere changes. In this study, we calculated the PDD based on the daily mean temperatures from 1960 to 2018 at meteorological stations, and we used measured and interpolated data to determine spatial and temporal distribution and changes in PDD in western China (WC). Results show that the mean annual, warm season, and cold season PDD values at 209 meteorological stations were 3652.2, 2832.9, and 819.3 °C, respectively. PDD spatial distribution in WC is similar to that of air temperature. In WC, PDD mainly ranged from 0 to 5000, 1000 to 4000, and 0 to 1000 °C year−1, respectively for annual, warm season, and cold season. From 1960 to 2018, the observed mean initial day of PDD moved forward by 8.3 days, and the final day was delayed by 8.2 days, with the duration expanding to 16.6 days; the trend in PDD reversed in the 1980s and the change rate in PDD for annual, warm season and cold season was 6.6, 3.8, and 2.7 °C year−1, respectively. Regionally, PDD increased in almost all areas; the high PDD advanced from south to north, east to west, desert to mountain, and low to high altitudes. The results also showed that the warming rate of PDD was lower in the cold season and in high-altitude areas, which was opposite to the observed temperature patterns, however, the non-linear relationship between PDD and mean temperature over a period of time is the main reason for this phenomenon. This study adds more details for the understanding of climate change in WC, and suggests that more attention should be paid to PDD in the study of cryosphere changes. [ABSTRACT FROM AUTHOR]